1er CONGRESO VIRTUAL DE CARDIOLOGIA
RESUMENES DE TEMAS LIBRES

CIRUGIA CARDIOVASCULAR

 

2390
Alta temprana en el postoperatorio de cirugía cardíaca

Schiro Gustavo, Garberi Javier, Farias Ruben, Alvarado Julio, Ruiz Roberto
Sanatorio La Entrerriana. Paraná. Entre Rios

Introducción: Dada la alta dependencia de las instituciones del interior del país de las obras sociales con sistemas capitados y/o modulados, se hace imprescindible bajar los costos. La reducción de los días de internación es vista como una solución y para ello los programas de alta temprana (AT) se utilizan cada vez más.
Objetivo: Determinar la factibilidad de aplicar este tipo de programas en una institución del interior con bajo volumen de pacientes (P).
Métodos: Se incluyeron a todos los P que se operaron en forma consecutiva durante el año 1998, analizándose el tipo de cirugía, los tiempos de circulación extracorpórea (CEC), de clampeo (TCL), de extubación (TE), de estadía en cuidados intensivos (TCI) y total de internación (TTI), la mortalidad (M), reinternación dentro de los 30 días (TRI), y complicaciones (C).
Resultados: 41 P, edad promedio 57,31 años (20-78); 31 varones y 10 mujeres, realizándose 28 cirugías de revascularización (CRM), 11 reemplazos valvulares, 1 cierre de CIA y 1 CRM más resección de aneurisma ventricular. El 85,71% de las CRM recibió 3 bypass, 39,28 % con mamaria interna y 10,71 % con radial. El CEC medio fue de 114´ y el TCL de 64´. El TE promedio fue de 6 hs, el TCI 48 hs y el TTI 5, 23 días, con una M de 4,87% (2P). La TRI fue de 7,69 % (3P) y las C: infarto perioperatorio 7.32%, aleteo auricular 2,44%, sangrado 10,25%, reoperación por sangrado 5% y síndrome de respuesta inflamatoria sistemica 2,44 %.
Conclusión: Los programas de AT son factibles de aplicar en este tipo de institución con baja tasa de complicaciones, mortalidad y reinternación.

2314
Aortic valve preserving by descalcification: an old technique revisited

Kalil Renato AK, Teixeira Fº Guaracy F, Sant’Anna João RM, Prates Paulo R, Prates Paulo R.L, Wender Orlando C, Nesralla Ivo A
Instituto de Cardiologia do Rio Grande do Sul/Fundação Universitária de Cardiologia. Porto Alegre. RS. Brasil

Aortic valve preserving in calcific stenosis was almost abandoned in favor of prosthetic replacement. Ultrasonic debridement has not become popular. Some series, however, report good long term results after mechanical debridement. This paper presents medium term results of consecutive treatment in senile and congenital calcified aortic stenosis, in a prospective, non-randomized study. From 1993 to 1996, 85 patients were operated on for calcific aortic stenosis. In 62 (72.1%) the valve was preserved. Those were 33 male and 29 female, with age range from 25 to 78 (61.7 ± 10.5) years. Myocardial revasculatization and/or mitral valve surgery was done in 17 (27.4%). Myocardial ischemic time was 20 to 78 (37.1 ± 13.0) min and total perfusion, 33 to 120 (57.1 ± 17.9) min. Ethiology was congenital in 30 (49.2%) and senile in 32 (50.8%).
Surgical technique consisted in fragmentation and dislodgement of calcific deposits, debridement, comissurotomy and, eventually, repair of small holes in leaflets. The patients were followed-up from 10 days to 46 months, clinically and by echocardiograms.
Mortality was 3.2% (2 cases) early and 3.2% (2) late. One patient (1.6%) was reoperated for mitral and aortic stenosis, after 45 months. Late NYHA functional class was I in 42.9%, II in 50.0% and III in 7.1%. Echo results: median aortic gradient preop 50.6 ± 20.2 mmHg, p.o. 19.3 ± 4.0 mmHg (p<0.01) and late p.o. 26.6 ± 12.7 mmHg (NS); septal width preop 14.7 ± 0.5 mm, p.o. 11.6 ± 0.2 mm (p<0.01) and late p.o. 12.0 ± 0.1 mm (NS).
Aortic valve preserving in calcified stenosis, senile or congenital, provides adequate obstruction relief and hypertrophy regression with good clinical result, at least on medium term follow-up. This is a realistic and preferential alternative to valve replacement.

2379
Aortic valve replacement with small-size disc prostheses (Medtronic-Hall)

António J Brazão, David Prieto, J Ferrão de Oliveira, Luís Eugénio, Manuel J Antunes
Cardiothoracic Surgery, University Hospital. Coimbra. Portugal

Background and aim of the study: Several works have demonstrated worse performance of small prostheses in the narrow aortic root. However, modern low profile mechanical prostheses are easy to implant and have been increasingly used in elderly patients, where narrow roots are frequently observed. We describe our experience in patients with aortic annuli < 21mm with Medtronic-Hall prostheses.
Patients and methods: From April 1988 through December 1997, 332 Medtronic-Hall size 20 (140 patients; 42.2%), 21 (96; 28.9%), 22 (96; 28.9%) prostheses were used. There were 218 females (65.7%) and the mean age was 59.3 + 9.8 years (29-75 years). Mean body surface area was 1.59 + 0.12 m2 (1.27 - 2.01m2). NYHA classes III/IV were present in 140 patients (42,2%). There were no significant differences in the clinical characteristics of the 3 groups.
Results: Mean pre-operative systolic LV/aorta gradient was 64.5 + 24.8 mmHg. After cardio-pulmonary bypass, peak gradients through the aortic prostheses were 13.9 + 8.0 mmHg in size 20, 14.0 + 8.1 mmHg in size 21 and 10.1 + 8.9 mmHg in size 22. Four patients (1.2%) died in hospital. There were no significant differences in hospital morbidity among the patients in the 3 groups. The follow-up was complete for 96.2% of the patients (mean 4.2 years; range 1-11 years). Late mortality was 9.3% (31 patients; 2.4%/pt/yr). Twenty patients (14.3%) had size 20 prostheses, 7 (7.3%) size 21 and 4 (4.2%) size 22 (p = ns). Sixteen patients (4.8%) died of cardiac causes, but only 7 (2.1%) of prosthetic-related causes, including sudden death. Preoperative older age and aortic regurgitation were the only independent predictors of late mortality. Eight patients had systemic T-E events (0.6%/pt/yr), 2 had prosthetic thrombosis (0.2%/pt/yr) and 5 had haemorrhagic episodes (0.4%/pt/yr). Seven patients had PVE (0.6%/pt/yr). Ninety percent of the survivors are in NYHA class I/II.
Conclusions: The small (20, 21 and 22) Medtronic-Hall prostheses have good haemodynamic performance and are an excellent option as valve substitutes in patients with narrow aortic roots.

2794
Cardiomyoplasty: present and future

JC Chachques, A Carpentier
Department of Cardiac Surgery, Broussais Hospital. Paris. France

A large proportion of the end stage heart failure patients need a therapeutic approach other than the current standard modalities, due to the restricted number of heart donors and the high cost and drawbacks of mechanical assist devices. It is clear that there is an international need for autologous biological heart support systems. The aim of CMP is to restore or enhance the myocardial contractility using the patient’s latissimus dorsi muscle which is wrapped around the ventricles and electrostimulated in synchrony with the contractions of the heart. The electostimulation is carried out with the aid of an implantable specific pacemaker (Cardio-myostimulator).
Following the first clinical case of cardiomyoplasty, performed at the Broussais Hospital, more than 1500 patients have undergone this procedure worldwide. At our institution, 111 patients have since been operated upon. Functional improvements and survival benefit have been observed by the majority of surgical and cardiological groups working in cardiomyoplasty. Evaluation with ventricular pressure-volume loop analysis, Doppler tissue imaging, ultrafast CT scan, and radioisotopic studies has provided objective and convincing data underlining the mechanism of these functional improvements. It was possible to demonstrate in the majority of cardiomyoplasty cases the improvement in systolic and diastolic function, as well as, the positive modifications in ventricular geometry. These studies have also demonstrated the need for precise muscle electrostimulation parameters for each patient.
The current research programs on cardiomyoplasty are encouraging, they include: 1: the use of angiogenic and myogenic growth factors to prevent latissimus dorsi muscle atrophy and to increase the heart/muscle collateral circulation; 2: the modification of the postoperative electrostimulation protocol (using a half-day intermittent muscle pacing: "demand cardiomyoplasty"); 3: the use of minimally invasive video-assisted surgical techniques (the last 10 cases at Broussais Hospital have been performed using this approach). There has been a new tendency to associate cardiomyoplasty with electrophysiological therapy. These therapies include the implantation of ventricular defibrillators, cardiac multisite pacing, and the induction of a permanent AV block with subsequent cardiac pacing in cardiomyoplasty patients suffering from atrial fibrillation.
The clinical use of aortomyoplasty is emerging. More than 50 patients have been operated worldwide. In this approach the electrostimulated latissimus dorsi muscle compresses the aorta during diastole, reproducing the hemodynamic effects of intra-aortic balloon counterpulsation.

2322
Clinical evidence of radial artery spasm immediately after coronary artery bypass graft surgery

Bonaccorsi Héctor, Bauduccio Claudio, Sgrosso José, Dogliotti Ariel
Instituto Cardiovascular de Rosario. Rosario. Argentina

Introduction: More than 20 years ago, shortly after its introduction in surgical practice, the bypass with radial artery (RA) was abandoned due to the high incidende of early occlusion presumably caused by its spasm.[1] In the begining of this decade its use was revitalized in belief that the availability of new spasmolitic drugs will make the RA in a highly convenient graft to coronary arteries bypass surgery.[1] However there are very few communications that inform the present incidence and the clinical characteristics of the spasms episodies of this arteria in the inmediate postoperative of coronary artery bypass graft surgery (CABG).

2694
Comparison between double balloon and Inoue techniques for percutaneous mitral valvuloplasty

Wisner Jorge, Mendiz Oscar, Telayna Juan, Menendez Marcelo, Valdivieso Leon, Londero Hugo
Departamento de Hemodinamia e Intervenciones por Cateterismo. Instituto de Cardiología y Cirugía Cardiovascular. Fundación Favaloro. Buenos Aires. Argentina

Objectives: To compare clinical and hemodynamics results between the double balloon technique (DBT) and Inoue technique (IT) for percutaneous mitral valvuloplasty.
Population: Between 1992 and 1998 134 patients were treated. IT was used in 105 patients and DBT in 29. Selection of the technique was based on operator preference and there were no predetermined criteria.
Results: In 113 patients (84.3%) clinical success was achieved, 12 (8.9%) had SOR and 8 (5.9%) developed a Severe Mitral Regurgitation (MR). The incidence of major complication was 6.7%.

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Multivariate analysis with linear regression showed that the basal gradient (p < 0.0005) and DBT (p < 0.03) were independent predictors of major final valve area.
Conclusion: Better hemodynamics results were obtained with DBT, in patients with worse Wilkins score. Clinical results were better too, but the difference did not reach statistical significance probably because of the small number of patients in this group.

2566
Coronary anastomosis with mechanical sutures: the VCS vascular clips. Initial experience

Aramendi JI, Otero A, Martinez P
Hospital de Cruces. Baracaldo. Spain

Objectives: To obtain a wide and easy to perform vascular anastomosis with the aid of mechanical sutures.
Methods: The VCS system (Autosuture) is an automatic stapling device that applies vascular clips with the shape of the African ant’s jaw. The clip stays entirely extravascular, hopefully producing no fibroblast proliferation. Due to its predetermined shape they grasp a minimal bite of the vessel border in an everting fashion, therefore allowing an anastomosis as wide as possible. The wall of the grafted vessel must be flexible and exempt of calcifications.
Results: Our initial experience consists in 3 cases that underwent coronary a. bypass grafting. One patient was operated without the aid of cardiopulmonary bypass and the other 2 with CPB. 5 out of 8 distal anastomosis were done with the VCS clips, 3 saphenous v. grafts and 2 LIMA grafts. 2 stay sutures of Prolene were applied at the heel and toe of the anastomosis to facilitate exposure. The last patients had all the distal anastomosis performed with VCS clips. No mortality nor complications resulted from the use of this device.
Conclusions: The VCS clips permits to perform a wider anastomosis that with conventional suture. With experience it can be easily and quickly done. It can be an important tool for minimally invasive surgery and by avoiding sutures and knots it can be it can be an important step towards endoscopical anastomosis.

2380
Coronary revascularization with free right internal thoracic artery: operative results in 789 patients

Antunes Pedro, Ferrão de Oliveira José, Antunes Manuel
Cardiothoracic Surgery. University Hospital. Coimbra. Portugal

Objectives: This study evaluates the perioperative mortality and morbidity of patients having a free right internal thoracic artery (FRITA)-to-coronary artery graft as part of their coronary revascularization.
Methods: From January 1992 to December 1998, 789 patients had a FRITA graft. Preoperative characteristics include: mean age, 57.2 ± 7.4 years; male sex, 759 (96.2%); diabetes, 95 (12.0%); previous myocardial infarction, 473 (59.9%); three-vessel disease, 472 (89.9%); left main disease, 106 (13.4%); left ventricular ejection fraction < 40%, 99 (12.5%). In 6 patients (0.6%) the FRITA was the only arterial graft used, and in 783 (99.4%) a pedicled left internal thoracic graft was also used. The mean number of grafts per patient was 3.2 ± 1.0 (2.1 ITA grafts/patient), and endarterectomies were performed in 52 patients (6.6%). The FRITA was used to reach the circumflex marginal branches in 605 patients (76.6%), the right coronary artery or its branches in 91 (11.5%), and diagonal or ramus intermedius in 90 (11.4%). The proximal anastomosis was constructed over a venous graft in 702 patients (88.9%) and directly onto the aortic wall in the remainder. Cardiopulmonary bypass time was 79.4 ± 8.9 minutes.
Results: Perioperative mortality was 0.7% (6 patients). Only 55 patients (6.9%) required inotropes, and 11 (1.4%) intra-aortic counterpulsation and / or left ventricular assist device. The incidence of myocardial infarction was 3.5%. Eighteen patients (2.4%) had reintervention for haemorrhage and 30 (3.8%) for sternal complications, without sequelae. The incidences of respiratory failure, renal failure and cerebrovascular accident were 0.8%, 1.9% and 1.6%, respectively. The mean time of hospital stay was 7.5 ± 6.1 days.
Conclusion: The use of the right internal thoracic artery as a free graft was associated with a low incidence of perioperative mortality and morbidity and allowed greater operative flexibility in arterial coronary revascularization.

2576
Coronary surgery without cardiopulmonary bypass

Aramendi JI, Castellanos E, Llorente A, Aldamiz-Echevarria G, Otero A, Martínez P
Hospital de Cruces. Barakaldo. Spain

Objectives: To analyze our initial results with off-pump coronary a. surgery.
Methods: Since December 1993 to February 1999, 119 consecutive patients underwent coronary a. bypass surgery without cardiopulmonary bypass (CPB). Of them 95 via a median sternotomy and 24 via a small left anterior thoracotomy (LAST). Mean age was 63 yr. (32-83). Type of disease: 1 vessel disease 54 pts. 2 vessel disease 49 pts. 3 vessel disease 4 pts. and left main coronary a. disease 12 pts. N of grafts per patient was: 1 graft in 72 pts., 2 grafts in 46 pts. And 3 grafts in 1 pt.(mean 1.5 per patient). 15 patients were operated upon on an emergency basis (mostly failed PTCA cases).
Results: There were 4 hospital deaths (3.3%): 4.3% for median sternotomy group (1% for elective cases) and 0% for LAST group (p = ns). There were 2 instances of posToprative bleeding, postop. Myocardial infarction and mediastinitis, all of them in the median sternotomy group (2.1%). Graft patency was assessed in 54 pts.(44%) by angiography in 39 pts. and Echo-Doppler in 15 pts.(LAST): of 79 grafts tested there were 3 occlusions (2 saphenous v. and 1 LIMA) and 2 LIMA grafts stenosis. Patency rate was 94%. 4 patients required reoperation (3%) 3 of them without CPB. Blood transfusion was avoided in 77% of LAST patients vs. 28% in the mean sternotomy group. Most of LAST pts. were dismissed at the 4th or 5th postop. day.
Conclusions: coronary a. surgery without CPB is a safe and low risk operation. Graft patency is equivalent to conventional surgery and complications rate lower. Nevertheless median sternotomy still carries a definite risk of bleeding and mediastinitis. LAST operation seems to offer better results as far as mortality, morbidity and blood transfusion requirements are concerned. It also offers a faster recovery.

2323
Quantifying risk in cardiovascular surgery

Bonaccorsi Héctor, Sosa Pamela, Sgrosso José, Ameriso José, Dogliotti Ariel
Instituto Cardiovascular de Rosario. Rosario. Argentina

Introduction: In present days world demand in quality and efficiency, both in the manufacture of the products and services, grows day by day. Medicine is not an exception. Although this is stronger in developed countries, it seems to be widening all over the world. The forementioned it is specially true with cardiovascular surgery since this is an expensive and very frequent procedure.
However, since long time ago, there is agreement in thinking that mortality because of this kind of procedures depends on not only the quality of care, but also the stage of the patient´s previous illness and hazard [1,2]. The subsequent inference that worse population means worse results, led concerned people to design systems with which taking into account the patient´s preoperative characteristics one could anticipate the surgical outcome and in that way make the quality control more accurate.
Therefore cardiovascular surgery results are required by the patients themselves, by the doctors and by the institutions that render the service and by the ones which pay for it.
To summarize, the risk stratification in cardiovascular surgery is useful to make clinical decisions, assessing quality of care and the administrative management related to the procedure.

2560
Extracción y disección de la vena safena para su utilización como injerto aorto-coronario con sistema endoscopico vasoview

Lara Juan, Cordera Silvia, Alvarez Miguel, Abdallah Abdul, Moreno Teo, Lopez-Checa Salvador, Calleja Manuel, Santalla Antonio, Fernández Rafael, Telleria Alberto, Palacios Angela, Franco Rafael
Cirugía Cardiovascular. Hospital Universitario Virgen de las Nieves. Granada. España

Introducción: Actualmente, la cantidad de vena safena requerida para injertos coronarios tiende a disminuir por la tendencia a usar injertos de naturaleza arterial, no obstante la obtención de vena safena sigue siendo parte esencial en la cirugía de revascularización coronaria.
Objetivos: Analizamos nuestra experiencia inicial en un grupo de pacientes en los cuales realizamos disección endoscópica de la vena safena con sistema vasoview.
Métodos: Desde Julio/98, 41 pacientes fueron sometidos a disección endoscópica con sistema vasoview. Con dos incisiones de 1.5-2.0 cm en ingle y rodilla, y una en tobillo, es posible extraer completamente la vena safena interna para utilizarla como injerto coronario. El sistema tiene un trocar-balón y un dispositivo Uniport para electrocoagular colaterales venosas, utilizando un sistema de sellado y CO2.
Resultados: No hubo infección en ninguno de los 41 pacientes operados con este sistema. Tampoco hubo IAM en ninguno de los territorios coronarios revascularizados con vena safena extraída con sistema endoscópico vasoview; el control de IAM fue realizado con cifras de CPK, mioglobina y troponina I. El grado de satisfacción de los pacientes con el aspecto cosmético de la herida fue alto frente al sistema convencional.
Conclusiones: Tras un periodo de aprendizaje, la extracción de la vena safena con sistema vasoview es gratificante y no requiere mas tiempo del utilizado con la técnica habitual, oscilando en nuestra experiencia desde 20 minutos hasta 90 en la fase inicial. Las ventajas cosméticas son destacables y en la población de riesgo por obesidad, diabetes etc las infecciones son menores.

2562
Factores relacionados con la mortalidad hospitalaria de la cirugía de revascularización sin circulación extracorpórea

Cordera Silvia, Alvarez Miguel, Lara Juan, Calleja Manuel, Colmenero Manuel, Barranco Mercedes, Santalla Antonio, López-Checa Salvador, Moreno Teodoro
Hospital Universitario Virgen de las Nieves. Granada. España

Introducción: La cirugía coronaria sin circulación extracorpórea (CRC-sCEC) se está introduciendo paulatinamente en pacientes con alto riesgo quirúrgico y/o con enfermedad monovaso.
Objetivo: Evaluar los factores relacionados con la mortalidad hospitalaria de la CRC-sCEC.
Material y métodos: 75 pacientes (61 ± 9 años, 85% hombres). Tenían IAM previo el 24%, el grado medio de angina era III. Se usó el índice de Parsonnet modificado (PM) como score de predicción de mortalidad, siendo de 2.2 ± 2.5 (0-13) en el total del grupo. Se consideró como urgente la cirugía que se llevó a cabo durante el ingreso hospitalario en que se realizó el diagnóstico (siempre más de 24 horas tras éste).
Resultados: La mortalidad hospitalaria observada fue del 6.8% (5 pacientes). No hubo diferencias en la edad, sexo, angina previa, IAM previo, fracción de eyección del ventrículo izquierdo, número de anastomosis distales, número de injertos arteriales, calidad de los lechos distales, uso de balón de contrapulsación, IAM perioperatorio, niveles de enzimas cardíacas. Los pacientes fallecidos tenían un índice de Parsonnet modificado superior (7.2 ± 4.6 vs 1.8 ± 1.8; p = 0.06). El carácter urgente de la cirugía fue más frecuente en el grupo de pacientes fallecidos (22.2% vs 1.8%; p < 0.05). Asimismo, el uso de inotropos en el período perioperatorio se asoció con una mayor mortalidad (20% vs 1.9%; p < 0.05).
Discusión: En esta serie de pacientes a los que se les realizó revascularización sin CEC la mortalidad hospitalaria se asoció con el carácter urgente de la CRC, con el score de predicción de riesgo y con el uso de inotropos. No se realizó análisis multivariable dado el escaso número de pacientes fallecidos.
Conclusiones: La mortalidad hospitalaria de la cirugía de revascularización sin CEC se asocia fundamentalmente con características preoperatorias, no relacionándose con factores dependientes de la técnica quirúrgica (número de anastomosis distales, número de injertos arteriales) ni con el IAM perioperatorio.

2484
Intraortic ballon pump. A new solution for an old problem

Almeida R.M.S.S.A.
Serviço de Cirurgia Cardiovascular. Instituto de Moléstias Cardiovasculares de Cascavel. Cascavel. Paraná. Brasil

Objective: To show the post-operative results after intraortic ballon pump insertion with a new surgical technique.
Patients and methods: Between August of 1994 and June of 1999, 1400 cardiac surgery procedures were performed, 931 of them being pump cases. Of this 32 (3.48%) had left ventricular assistance, with intra aortic balloon counterpulsation. The mean age was 55 years, being 19 (55%) males patients. Coronary artery disease was present in 22 (68.75%) patients. In 22 cases the balloon was installed as an emergency, being 16 in the operating room and 6 in the intensive care unit; in 10 (31.25%) it was installed electively. The insertion technique was performed by a surgical cut down to the femoral artery. A saphenous, homo or autologous, graft was then sewn to the common femoral artery in and end-to-side fashion. The balloon was introduced into the artery through the graft and properly positioned, and the balloon catether secured to the graft on it’s the distal portion. The balloon removal was done with local anesthesia, and required no second operation, only by taking off the stitch securing the vein to the balloon, and bearing the vein, after it’s occlusion.
Results: The overall survival was 47%, being 80% in the elective group. Mean pumping time was 54.5 hours for the survival group. In no case was the mortality due to the insertion technique, and the complication rate was 6.25%, due to severe peripheral vascular disease in two cases.
Conclusions: The authors conclude that this is a viable and easy reproducible technique, and has the advantage of not having to do another cut down, for balloon removal, or using prosthetic material.

2483
Left mamary artery flow in coronary mamary by-pass

Orlandi Fábio, Grossmann Rosana, Hublard Ernesto Luiz, Cortese Marcelo, Nakajima Eliza, Capellini Luis Fernando, Mangione José Armando, Beltrão Pedro, Cividanes Gil Vicente, Puig Luis Boro, Gebara Otávio, Del Castillo José Maria
Instituto de Cardiologia de São Paulo, Hospital Santa Paula. São Paulo, SP. Brasil

Purpose: Determine the best line of access to evaluate the coronary mamary by-pass through transtoracic echocardiography (TTE) and determine the internal mamary artery (IMA) pattern of flow in cases without stenosis, with stenosis, and with occlusion.
Material and methods: It has been studied 32 consecutive patients revascularized by coronary mamary by-pass, all males , average age 56 years. It has also been studied, as controls, 10 individuals who had never been submitted to coronary by-pass surgery, all males, average age 47 years. All patients have been submitted to digital coronary angiography. It has been visualized by TTE the internal mamary artery (IMA). Its diameter was measured, its flow has been registered and it has been calculated the diastolic integral velocity, systolic integral velocity and the resistance index.
Results: IMA satisfactory visualization and arterial flow register has been obtained in 26 patients (81%) and in 6 controls (60%) . Controls had high resistance flow patterns (systemic artery pattern) while in the revascularized patients the flow patterns varied from bifasic with diastolic prevalence (cases without stenosis or with mild/moderate stenosis) to bifasic with systolic prevalence (cases with severe degree of stenosis). In revascularized patients the best line of examination has been paraesternal incidence in third or fourth intercostal spaces, while in controls the best line has been the supra or infraclavicular route.
Conclusion: TTE, with the use of high frequency transducers, is a good method to assess IMA flow patterns in patients with coronary mamary by-pass. Left paraesternal incidence is the best line of examination. The IMA flow pattern allows the diferenciation of patients with severe stenosis and patients without stenosis or mild/moderate stenosi.

2595
Myocardial revascularization with left anterior small thoracotomy (LAST Operation): results in 71 patients

Leal JC, Braile DM, Godoy MF, Paiva O, Braile V
Braile Cardiocirugia e Hospital Beneficência Portuguesa. S. J. Rio Preto, SP. Brasil

Objective: To present the experience with myocardial revascularization by minimally Invasive surgery via left anterior small thoracotomy ( LAST Operation ) without extracorporeal circulation.
Material and methods: 71 patients, 49 males, were undergoing to LAST Operation from February 1997 to march 1999. Everyone has obstrutive disease in the proximal portion of the interventricular descending artery (IDA). The technique consisted of a small transverse incision, of about 9.0 cm, traverse, in the left infra mamary area, allowing good visibility and easy access for dissection of the thoracic internal artery (TIA) and anastomosis with IDA.The evalution of the results was madde by clinical, laboratory ( CKMb and Troponin I cardiac ) and angiographic control.
Results: The mean duration of operation was 2 half hours with about 24 hours of permanence in ICU and 5 days of maximum hospital stay. There were no intra-operative deaths.There was a case of sudden death after discharge (15 post-operative). The patients followed did not refer anginal pain. Four cases of TIA acclusion and 2 AIA stenoses were documented, probably secondary to vessel banding during the procedure.There was no correlation between troponin-I blood levels and acclusion of the graft.It was verified that the levels of troponon-I patients submitted to LAST Operation were significantly lower than in the conventional procedure. There was no significant clinical complication.
Conclusions: LAST Operation has no proved to be a useful procedure with low morbidity and mortality, with the possibility of shorter hospital stay and consequent lower cost. The low troponin-I blood levels indicate reduced myocardial injury during the procedure. 

2383
Non-cardioplegic coronary surgery in patients with poor left ventricular function

Antunes Manuel, Antunes Pedro, Ferrão de Oliveira José
Cardiothoracic Surgery, University Hospital. Coimbra. Portugal

Objectives: This study evaluates the perioperative mortality and morbidity in patients with severe left ventricular dysfunction submitted to CABG using non-cardioplegic methods.
Methods: Between April 1990 and December 1997, 3180 patients were consecutively subjected to isolated CABG using non-cardioplegic methods for construction of the distal anastomoses. This prospective study is based on the 107 (3.5%) patients with severe impairment of the left ventricular function (ejection fraction < 30%). Intermittent aortic cross-clamping was used in 17 patients, until June 1992, and ventricular fibrillation in 90 patients. The mean age at operation was 57.0 ± 9.2 years and 95.3% of patients were male. Fifty three patients (49.5%) were in CCS class III-IV and 12 (11.2%) were subjected to urgent surgery. A history of previous myocardial infarction was recorded in 99 (92.5%) patients. Ninety seven (90.6%) patients had triple vessel and 17 (15.9%) left main stem disease, and 77 (71.9%) had a left ventricular end-diastolic pressure > 20 mmHg. Cardiopulmonary bypass time was 73.1 ± 21.7 min. The mean number of grafts per patient was 3.2 and at least one internal mammary artery was used in all cases (1.2 arterial grafts/patient). Endarterectomies were performed in 23 (21.5%) patients.
Results: Perioperative mortality was 2.8% (respiratory-1; cardiac-2). The incidence of myocardial infarction was 2.4%. Forty one (38.3%) patients required inotropes, but for longer than 24 hours in only 12 (11.2%), two (1.9%) intra-aortic counterpulsation and three (2.8%) left ventricular assiste device. Two (2.4%) patients had reintervention for hemorrhage and another five (4.6%) for sternal complications. The incidences of supra-ventricular arrhythmias, renal failure and cerebrovascular accident were 17.0%, 3.6%, and 2.4%, respectively. The mean hospital stay was 9.3 ± 6.4 days.
Conclusion: These results appear to demonstrate that non-cardioplegic methods afford good myocardial protection and operating conditions with excellent applicability, even in patients with severe left ventricular dysfunction.

2382
Open mitral commissurotomy. The golden standard

Antunes MJ, Vieira H, Ferrão de Oliveira J
Cardiothoracic Surgery. University Hospital. Coimbra. Portugal

Objective: Percutaneous balloon mitral commissurotomy (PBMC) has recently emerged as an alternative to surgical commissurotomy for the treatment of rheumatic mitral valve stenosis. However, this blind procedure may result in incomplete separation of the commissures which could lead to accelerated restenosis. Hence, open mitral commissurotomy (OMC), which is a visually oriented procedure remains our method of choice. This work aimed at assessing its long-term results.
Methods and results: In a series of OMC performed from 1988 to 1991, involving 100 mitral valves with an echocardiographic score £ 10, we were able to achieve mean valve areas of 2.88 ± 0.49cm2, from a mean of 0.99 ± 0.23cm2 preoperatively. In a recent follow-up, conducted after a mean of 8 years (7-11 years), the valve areas measured by echo-Doppler in this group of patients were 2.37 ± 0.42cm2 (range 1.6–3.6 cm2) and 81% had a valve area > 2.0 cm2. Reoperation was required in only two patients. Late mortality was 4%, (0.5% pt.yr) in no case valve-related. Two-thirds of the patients had no or only mild mitral insufficiency. Ninety three percent were in NYHA class I or II. The 9-year actuarial survival was 96%, freedom from reoperation was 98% and freedom from all valve-related complications was 92%. Complementary to this experience, in the past 10 years we were able to perform modified OMC in 919 (79%) of all 1,151 patients with mitral stenosis submitted to surgery, including 257 with mixed disease. The mean post-commissurotomy valve area (2.9 cm2) was identical to that of the study group. Moderate to severe valve calcification was not an absolute contra-indication to valve conservation.
Conclusion: OMC remains the best alternative for the treatment of all cases of mitral stenosis, independently of the degree of pliability. In our experience, the medium and long-term results are significantly better than those usually reported in PMBC series.

2419
Patency of in-situ left internal thoracic artery grafts to the left anterior descending coronary arteries with non critical stenoses

Buxton B, Fuller J, Tatoulis J, Gordon I, Ruengsakulrach P
Austin & Repatriation Medical Centre, Epworth Hospital and Statistical Consulting Centre. Melbourne University. Melbourne. Australia

Background: Excellent 10-year patency can be expected when the left internal thoracic artery (LITA) is anastomosed to the left anterior descending coronary artery (LAD) beyond a stenosis _ 80%; the results of the LITA anastomosed to the LAD with low grade stenosis are not so well documented.
Patients: Between 1984 and 1998, 11,485 patients underwent primary coronary artery surgery using an in-situ LITA graft to the LAD. The severity of the LAD stenosis was estimated by angiography. 654 of these patients (5.7%) had reangiography for clinical evidence suggesting myocardial ischemia. The mean follow-up was 65.4 ± 40.2 months (mean ± SD) with a total follow up of 39,839 patient-months.
Methods: Graft failure was defined as occlusion _ 80%, this included patients who had a string sign. Comparisons of graft patency were made between LAD stenosis < 60%, 60-79%, and 80-100% using the Kaplan-Meier method. Differences were assessed using the log-rank statistic.
Results: The probability of graft patency at 10 years is shown in Table. The 10-years failure rates were 19%, 9%, and 4%, respectively. There was no significant difference between the 3 groups.
Conclusion: These results suggest that the patency of in-situ LITA grafts to the LAD may be affected by competitive flow and may influence the decision to use these grafts in arteries with a minor stenosis.
Table: Patency of in-situ LITA to the LAD at 10 years.

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2418
Predictors of severe intimal disease in radial arteries for use in coronary artery surgery

Ruengsakulrach P, Sinclair R, Gordon I, Buxton B
Austin & Repatriation Medical Centre, Melbourne. Victoria. Australia

Objectives: Intimal hyperplasia is a major cause of graft failure. This study identified clinical factors associated with severe intimal hyperplasia and atherosclerosis in the radial artery (RA) and compared disease severity in the distal and proximal RA.
Methods: RA segments from 179 patients undergoing CABG were examined by histopathology and morphometry. Eighty-three paired segments of distal and proximal RA were compared morphometrically. Disease severity was evaluated by percentage of luminal narrowing (% LN)* and intimal thickness index (ITI)*. Nine potential clinical risk factors for vascular disease were analysed by stepwise linear regression. We set values of 50% for % LN and 0.5 for ITI as levels of serious concern, to be confident that graft arteries had lower values. Setting the upper limit of the 95% prediction interval equal to these values enabled us to determine clinical profiles of concern.
Results: Intimal hyperplasia and atherosclerosis were found in 92.7% (166/179) and 6.1% of RA (11/179), respectively. Significant (p < 0.05) predictors of severe intimal disease in RAs were aortoiliac disease, age and diabetes (see table). Morphometric analysis showed that the proximal RA had a significantly lower % LN compared with the distal RA (p < 0.001).
Conclusions: Predictors for severe intimal disease in the RA were identified. The distal RA is more likely than proximal RA to have severe intimal hyperplasia.
Table: Clinical predictors of significant intimal disease

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2555
Recuperação elétrica imediata do miocárdio com solução cardioplégica contínua em estudo experimental: resultados iniciais

Braile DM, Leal JC, Godoy MF
Braile Biomédica. Departamento de pesquisa e cirurgia experimental. S. J. Rio Preto. SP. Brasil

Introdução: São realizadas no mundo milhares de operações cardíacas com circulação extracorpórea a cada ano, não havendo ainda consenso a respeito do método mais adequado para proteger o miocárdio contra a agressão isquêmica, que ocorre durante esse procedimento.
Objetivo: Avaliar a recuperação elétrica imediata do coração de cobaia após período variáveis de isquêmia com e sem utilização da solução cardioplégica contínua.
Material e método: Foram estudados 28 corações de cobaias machos com peso corporal de 400 a 800 g e peso cardíaco de 2,1 a 5,3 g/ divididos em 3 grupos: Grupo 1 (controle–10 corações) infusão continua de Ringer Locke, Grupo 2 ( 9 corações) infusão cardioplégica contínua enriquecida com aminoácidos, fases de indução e manutenção. Grupo 3 (9 corações) infusão de solução cardioplégica, enriquecida com aminoácidos, apenas em fase de indução, sem manutenção. Os grupos foram submetidos a experimentos por 30,60,90,150,180,210 e 240 minutos. A escolha do grupo e da duração do experimento foram randomizadas. Os corações foram submetidos a estudo histopatológico, após cada experimento.
Resultados: A recuperação elétrica imediata no grupo 2 foi satisfatória comparado ao grupo 1, enquanto, o grupo 3 apresentou taquicardia ventricular e fibrilação ventricular em 6 (67%) dos casos, quando retomados os batimentos cardíacos. O estudo histopatológico mostrou o grupo 3, com tendência mais acentuada para alterações nas estruturas citoplasmáticas quando comparado aos grupos 1 e 2.
Conclusão: A recuperação cardíaca elétrica imediata, foi satisfatória com solução cardioplégica contínua, indução e manutenção, enriquecida com aminoácidos.

2345
Revascularización miocárdica con conductos arteriales

Medesani Luis Alberto
Instituto del Diagnóstico (La Plata). Fundación Mainetti (La Plata). Sanatorio Argentino (La Plata). Sanatorio Antártida (Buenos Aires). República Argentina

Introducción: Se han desarrollado diversas técnicas para revascularización miocárdica con la utilización de arteria mamaria interna (AMI) y conductos venosos, con resultados superiores para la primera, lo cual ha estimulado la búsqueda de conductos arteriales con similar éxito angiográfico en el largo plazo.
Objetivos: Analizar la experiencia del mismo grupo quirúrgico, con la utilización de conductos arteriales combinados con AMI izquierda en revascularización miocárdica.
Métodos: Se analizaron en forma prospectiva 51 pacientes en los cuales se utilizó arteria gastroepiploica en 15, radial en 32 y epigástrica en 4 pacientes, en combinación con AMI a descendente anterior (DA). En la población estudiada, 41 pacientes eran masculinos y 10 femeninos, con edad promedio de 56 años. Se efectuaron 143 puentes coronarios, (promedio 2,5 por paciente) analizando morbimortalidad intrahospitalaria y en el seguimiento a seis meses.
Resultados: En la fase hospitalaria, la mortalidad fue de 5,8%. La morbilidad fue: infarto perioperatorio no mortal en 5 pacientes (9,8%) todos con puentes de arteria epigástrica y radial a CX dominante. Neuritis de la mano en 1 paciente (1,8%). Durante el seguimiento falleció 1 paciente por ACV a los seis meses (2%), registrando 1 caso de angina Inestable . No se observaron nuevos eventos coronarios clínicos, en el seguimiento a seis meses en el 97,8% de los pacientes, siendo la mortalidad total de 7,8%.
Discusión: La utilización de conductos arteriales es un reto al decidir estrategias de revascularización. La arteria mamaria interna es de elección pero nos seguimos enfrentando a situaciones en las cuales resulta insuficiente.
Conclusiones: En esta serie se observó que la utilización de conductos arteriales es útil, con resultados aceptables comparados con otras series publicadas, con una baja incidencia de eventos en el seguimiento a seis meses.

2716
Revascularización miocárdica con injertos arteriales

Navarro Miguel, Rodriguez Campos Jorge, Canestri Alberto, Alvarez Eduardo, Chiappe Miguel
Servicio Cirugía Cardíaca- Instituto Modelo Cardiología. Córdoba. Argentina

Introducción: Desde que fueron demostrados los beneficios a largo plazo del uso de la lima, los distintos reportes que mostraban nuevamente el uso de la radial, las potenciales ventajas de los conductos arteriales sobre los venosos, se produjo un incremento significativo en la utilización de los mismos por distintos grupos quirúrgicos.
Objetivo: Analizar nuestra experiencia en pacientes revascularizados exclusivamente con conductos arteriales.
Material y métodos: Se analizó el tipo de injerto, la estrategia empleada, las coronarias revascularizadas y los resultados inmediatos en una serie de 100 pacientes consecutivos intervenidos entre febrero 1997 y abril 1999.
Resultados: Un total de 205 injertos fueron utilizados (2.05 p/paciente) el tipo de injerto empleado fue: lima en 95% de los casos, rima en 44%, radial en 49%, gead 15%, epigástrica en el 2%. La lima y la gead fueron usadas como injertos in situ en el 100%; de las radiales utilizadas 79.5% fueron anastomosadas en y a la lima mientras que las rima lo fueron en un 47.7% .Se realizaron 236 anastomosis distales (2.3 p/paciente). El 44% de los pacientes recibió doble mamaria.
Discusión: EL objetivo de lograr una revascularización completa con injertos arteriales considerando las potenciales ventajas sobre los venosos y así beneficiar electivamente a pacientes jovenes; y/o a aquellos en los que hay dificultad para la obtención de injertos venosos, implica ciertas variantes técnicas. La esqueletización de las mamarias nos permitió obtener un injerto de mayor longitud al habitual. Las anastomosis en Y se realizaron previamente a la entrada en bomba. La estrategia empleada estuvo supeditada a la anatomia como así también al tipo de oclusión coronaria. Si bien observamos un incremento en los tiempos quirúrgicos, los mismos no incidieron en los tiempos de circulación extracorpórea.
Conclusiones: La revascularización utilizando injertos arteriales es posible gracias a:1: la revalorización de conductos alternativos; 2: variantes técnicas (anastomosis en "y"- p. secuenciales- esqueletización.) con buenos resultados inmediatos

2818
Revascularización miocárdica total con conductos arteriales. Experiencia

Tomasini M, Ficarra A, Moll F, Pendino D
Servicio de Cirugía Torácica y Cardiovascular. Sanatorio Plaza Rosario. Santa Fe. Argentina

Se analiza una serie de 82 pacientes, 69 hombres y 13 mujeres con enfermedad coronaria severa, edad promedio de 68.5 años (rango 39-75) que fueron revascularizados con conductos arteriales exclusivamente. Ambas arterias se utilizaron en 45 pacientes 18 de los cuales con colgajo pediculado bilateral in situ y 17 con mamaria interna derecha como injerto libre en Y desde mamaria interna izquierda. Ambas arterias mamarias in situ y arteria radial en 28, ambas arterias mamarias y arteria epigástrica inferior en 9. La mortalidad perioperatoria fue del 4.8% (4 pacientes). El seguimiento promedio fue de 2.5 años. Diecisiete pacientes (20.7%) fueron reevaluados angiográficamente y el resto se controló mediante examen clínico y cámara gamma. Dos pacientes fallecieron en el postoperatorio alejado de causa no cardíaca. El uso de conductos arteriales permite una revascularización completa con mínima morbimortalidad en el corto y mediano plazo y su utilización es preferencial en pacientes de mediana edad.

2467
Revascularización multivaso en cirugía coronaria sin circulación extracorpórea. Abordaje quirúrgico de todas las arterias coronarias

Lara Juan, Cordera Silvia, Moreno Teodoro, Alvarez Miguel, Abdallah Abdul, Calleja Manuel, Santalla Antonio,  Lopez-Checa Salvador
Hospital Universitario Virgen de las Nieves. Granada. España.

Introducción: La cirugía de revascularización coronaria sin circulación extracorpórea (CEC), ha resurgido con fuerza en los últimos años y tiende a crecer tras haber estado limitada por la dificultad de acceder a las arterias coronarias de la cara posterior del corazón.
Objetivos: Revisar nuestra experiencia en cirugía coronaria sin CEC por esternotomía media (OPCAB) y por toracotomía izquierda (MIDCAB) o (LAST) y valorar los resultados frente a la cirugía de revascularización coronaria convencional.
Material y métodos: De 75 pacientes operados sin CEC, hubo 73 OPCAB y 2 MIDCAB por LAST; iniciamos nuestra experiencia con enfermos de uno o dos vasos y en la actualidad realizamos de rutina OPCAB en todos los pacientes independientemente del número de injertos o la naturaleza de los mismos. La técnica empleada fue, apertura lateral del pericardio (Benetti), maniobras de Trendelenburg, rotación derecha de la mesa, puntos de Lima, apertura de pleura y pericardio derecho según Hart, estabilización regional con CTS y OctopusII, shunts, intracoronarios o desde aorta, pocas drogas inotrópicas, no betabloqueo y mantenimiento de la normotermia.
Resultados: En 40% se realizaron tres ó más injertos coronarios (1-5), en los últimos 55 pacientes no se utilizaron criterios de exclusión para OPCAB, la mortalidad se relacionó con carácter de la cirugía, grado funcional y el score de Parsonet modificado.
Discusión: Los resultados obtenidos están en rango con la cirugía de revascularización con CEC, y creemos que tras la necesaria curva de aprendizaje los resultados pueden mejorar.
Conclusiones: La cirugía de revascularización multivaso en CEC actualmente es una técnica competitiva con la cirugía de revascularización convencional con CEC y cardioplegia.

2564
S–T changes after partial left ventriculectomy

Borut Gersak, Randas Jose Vilela Batista
Department of Cardiovascular Surgery, University Medical Center Ljubljana. Ljubljana. Slovenia.
Fundaçao do Coraçao Vilela Batista. Curitiba. Brasil

Introduction: We wanted to demonstrate cardiac electrophysiologic changes in patients where partial left ventriculectomy (PLV) was performed.
Objectives: Body surface potential mapping (BSPM) was used to study the EKG changes in the patients prior and after the PLV.
Material and methods: 11 patients were operated. EKG was performed from 35 and 31 measuring points. The same electrode positions were used for all the five measurements: prior to PLV, second, third, fourth and fifth postoperative day. The BSP maps were generated from a single beat.
Results: The ST40ms maps are showing the difference prior/after the operation. All the maps of the patients candidates for PLV before the operation are showing the same pattern, ST elevation over the anterior aspect of the heart and ST depression over the lateral and posterior aspect of the heart. All these patients had normal coronary angiography. After the operation the ST maps also showed the same pattern for all the patients. These maps haven’t changed significantly over the whole postoperative measurement period. The pattern in this period is a normalization of ST elevation over the anterior, lateral and posterior aspect of the heart, leaving the positivity over the excised area of the heart.
Discussion: With the BSPM system as described we are able to see the differences in the EKG and impulse propagation in the patients after PLV. This is a noninvasive method, perhaps could be used to study the patients after the PLV to see if they are likely to develop a fatal arrhythmia.
Conclusion: It would be necessary to compare the measured data of each individual patient with the data bank of the patients whose postoperative outcome will be studied in detail. This would be possible with the involvement of different centers worldwide, where the PLV operation is performed.

2381
Staged operations for severe carotid and coronary occlusive disease

Antunes Pedro, Ferrão de Oliveira José, Eugénio Luís, Antunes Manuel
Cardiothoracic Surgery. University Hospital. Coimbra. Portugal

Objectives: To demonstrate that staged, consecutive, carotid endarterectomy (CE) and coronary artery bypass grafting (CABG) is a safe, perhaps preferable, alternative for the treatment of patients with severe carotid and coronary artery disease.
Materials and methods: During a 7-year period ending December 1998, 60 (1.9%) of 3,242 consecutive patients who were referred for isolated coronary surgery were found to have significant carotid disease and underwent CE prior to CABG. The mean age of the patients was 65.0 ± 5.3 years and 46 (76.7 %) were male. The majority (81.6%) had triple vessel and 26.6% had left main disease. Carotid disease was unilateral in 54 patients ( 90.0%) and bilateral in 6 (10.0%), and 49 patients (81.6%) were neurologically asymptomatic. Only obstructions > 70% were considered for endarterectomy. All CEs were performed electively, but 5 patients (8.3%) had CABG performed on a urgent/emergent basis.
Results: Sixty six isolated CEs were performed with direct clamping of the artery (mean 19.6 ± 6.1 min) in all but one. There were no deaths. One patient (1.5%) had a stroke with permanent neurological deficit and two patients (3.0%) developed a myocardial infarction (MI). The mean admission time was 6.0 ± 3.5 days. The staging interval was 39.5 days. During coronary surgery, a mean of 2.9 coronary grafts/patient were performed and 98.3% received at least one IMA graft. One patient (1.7%) died. There were no MI and three patients (5.0%) had a stroke. The mean admission time was 8.6 ± 3.3 days. Hence, the global rates of perioperative mortality, MI and stroke were 1.7%, 4.7% and 6.5%, respectively.
Conclusion: In our practice, staging of carotid and coronary operations is the preferred surgical approach for these high risk patients and resulted in low global perioperative mortality and morbidity rates.

2342
Surgery for correction of anterior left ventricular aneurysm

Almeida RMSSA, Lima Jr. JD, Bastos LC, Flores EQ, Loures D
Serviço de Cirurgia Cardiovascular, Instituto de Moléstias Cardiovasculares de Cascavel. Hospital Policlínica de Cascavel. Cascavel. Paraná. Brasil

Objective: To show the peri-operative, medium and long-term results, of the left ventricular (LV) aneurysm surgical resection, due to ischemic disease.
Patients and methods: Between July of 1992 and June of 1999, 1400 cardiac surgeries were performed. Of the aorto-coronary artery bypass group of 436 patients, 12,8% were submitted to surgical resection of their anterior left ventricular aneurysms’, due to ischemic disease. Mean age was 57,1 years, being 67,8% men. There was a clinical history or electrocardiographic alterations, of myocardial infarction (MI), in 52 patients; in 16,1% MI was less than 30 days. The principal cause for surgical treatment was congestive heart failure, in 37 cases, class III or IV (NYHA), followed by angina in 17 cases and arrhythmia in two. Moderate to severe left ventricular dysfunction was present in 30 patients. Left ventricular mural thrombus were present in 26 patients, and from this group 2 had previous embolic cerebral stokes. In 54 cases the surgical approach for left ventricular aneurysm correction was the linear closure technique; in two recent cases, the Dor’s approach was used in patients with severe left ventricular dysfunction. Aorta-coronary artery by-pass grafting was additionally performed in 51 patients, and in 37 cases the coronary grafted, was the one responsible for the MI. A total of 104 grafts were performed.
Results: The hospital mortality was 1,8%. The intra-aortic balloon pump was used in three cases. In the late post-operative period six patients were study angiografically and found to have patent grafts and normal left ventricular function. Twelve patients had a 2-D Echo, post-operatively that showed improvement in L.V. function, including the resected area.
Conclusions: It is possible to perform repair of the left ventricle aneurysms’ with a low incidence of morbidity or mortality, and that patients benefit from concomitant coronary artery by-pass, to the infarcted area.

2407
Ten-year survival of patients treated for recurrent angina after prior bypass surgery: coronary angioplasty vs. repeat coronary bypass grafting vs. medical therapy

Pfautsch Peter, Frantz Eckart, Ellmer Axel, Sauer Hans-Ulrich, Fleck Eckart
Medical Clinic, Cardiology, Charité, Campus Virchow Clinic, Humboldt University and German Heart Institute. Berlin, Germany

Objectives: Although there are randomized data for CABG vs. medical therapy and CABG vs. PTCA in primary therapy of CAD, there is few evidence in the appropriate therapy of recurrent angina after prior CABG.
Methods: We retrospectively analyzed data from 1265 consecutive pts presenting with recurrent angina after previous CABG who required either re-CABG (n = 70), PTCA (n = 765) or med Rx (n = 430) 1986-1996.
Results: Post index-therapy outcome is monitored during 46,4 ± 30,6 (range 0-132) months. The 3 therapeutic groups were similar with respect to gender (84% male), age (Æ 60 years), prevalence of diabetes (21%), left ventricular ejection fraction (52%), number of grafts placed (2,7) and duration of post-CABG symptom-free interval (37 months). Actuarial survival was significant higher in the PTCA-group at 1, 5 and 10 years after index-therapy of recurrent angina (1-year-survival 95% vs. 95% medRX vs. 79% re-CABG, 5-year-survival 87% vs. 78% medRx vs. 51% re-CABG and 10-year-survial 69% vs. 64% medRx vs. 51% re-CABG resp., p < 0.0001). Similar results were found after adjustment for significant differences in basic data. Multivariate Cox-analysis identified LVEF < 35%, non-use of IMA-graft, age > 70 years, AMI post primary CABG and re-CABG as independent correlates for mortality for the entire group, angioplasty was identified as an independent correlate for survival.
Conclusion: In this nonrandomized series of patients with recurrent angina after previous CABG, an initial strategy of angioplasty resulted in a significant higher overall survival. These findings suggest to perform,if technically feasible, interventional revascularisation techniques in these patients in order to avoid repeat CABG.

2565
Heart-lung transplantation in a child with cystic fibrosis: first case in Argentina

Burgos Claudio, Siccardi María Alejandra, Mugianessi Oscar, Lemos Cecilia
Cardiovascular Service, Italian Hospital. Mendoza. Argentina

Introduction: Cystic fibrosis (CF) is a genetic disease common in white people. It affects 1 per 2,000 to 3,000 live birth and is autosomic recessive transmitted. It’s associated with generalized epithelial dysfunction. In respiratory tract more viscous secretion produces progressive airway obstruction with recurrent infections, respiratory insufficiency and parenchyma lung destruction. According to CF Foundation the mean of survival in these patients is 28 years and the first cause of death is respiratory failure. With actual medical cares, news antibiotics and gene therapy in investigation, heart-lung transplantation is in the last years an important option in several centers in the world.

2736
Celsior® Cardioplegic solution in orthotopic cardiac transplantation. A comparative study with Buckberg solution

Crespo FM, Rodríguez Delgadillo MA, Paladini G, Juffé Stein A
Servicio de Cirugía Cardíaca. Hospital Juan Canalejo. La Coruña. España

Introduction: Nowadays, cardiac transplantation seems to be the only treatment for end-stage heart failure, pathology that appears to be more and more frequent. Due to organ shortage to satisfy waiting lists requirements, alternative strategies appeared, generally not as definitive solutions but as palliative procedures (as cardiomyoplasty and aortomyoplasty). Donor election and management is the gold standard, if there is a good donor , results will be satisfactory.
One of the main causes of graft failure in cardiac transplantation, is functional alteration of the graft, that is shown since re-oxigenation of the transplanted organ is performed, and is usually ligated to the ischaemic time between cardiectomy and reimplantation. Depressed ventricular contraction is frequent in the postoperative period, mainly with marginal donors or long-distance ablation procedures, with more than 4 hours of ischaemic time, being this the limit in which injuries became irreversible.
Cardiac transplantation goes through different steps: 1: Donor cardiectomy an funcional preservation. 2: Transport. 3: Myocardial protection during reimplantation. 4: Reperfusion injuries. 5: Postoperative care. 6: Follow-up.
In each of these steps there are cellular and functional injuries, so it is our aim to avoid these alterations.
In order to minimize the risk, several authors have described the use of protective solutions either for cardiectomy perfusion, cold preservation or reimplantation reperfusion. This technical improves oin myocardial protection, permit us the use of "suboptimal" donors which probably, would have been rejected in the past.
Celsior® formulation joins the fundamental precepts of organ preservation and with those specific of myocardial metabolism. This formulation permits the use of Celsior® for all the steps of cardiac transplantation: initial cardioplegia, storage, ischaemia and reperfusion.

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The objectives of the formulation are the following:
* Prevention of edema achieved by impermeants present in the solution (Mannitol y Lactobionate).
* Prevention of oxidative damage caused by free radicals:
# Reduced Glutathione (GSH),strong antioxidant that inactivates oxygen, preserving its activity against free radicals.
# Mannitol which associates its osmotic effect with a hydroxile radical inactivator effect.
# Histidine, initially used for its low temperature buffer effect, it is also used as a free radical inactivator.

* Prevention of calcium overload:
# It is an apropiate ionic formulatio (low Calcium, moderate potassium, high levels of Sodium and Magnessium)
# Slight acidosis (correct pH levels are achieved by usig hitidine).

# An energy sustrate, Glutamate, that allows anaerobic production of high energy components, what leads to reduce the ATP component of calcium contraction (ionic modifications, as acidosis,acts over the calcium-dependient components of the contraction).
In our hospital, since the donor heart arrives, we use continuous normothermic blood cardioplegic solution, in a controlled perfusion, in order to heal potential hypothermic cellular damage (œdema, ionic calcium redistribution, an increase in coronary vascular resistances, inactivation of active mechanism as Na/K bomb).
We performed a comparative study in myocardial protection with intermitent cold blood cardioplegia (Buckberg´s technique) against continuous normothermic Celsior® cardioplegia.

2666
Variaciones en los niveles de la hormona T4 total en pacientes intervenidos por reemplazo valvular cardíaco con circulación extracorpórea

Corona Virón Pedro, Rodríguez Velayos Justino, Babé Pérez Alberto, Soria Delgado José Luis, Pérez Oviedo Miguel Angel, Pérez Piqueras José Luis
Hospital Militar del Rey. Las Palmas de Gran Canaria. España

Objetivos: Nuestro objetivo es analizar las variaciones en los niveles de la hormona T4 total durante y en los días siguientes a una intervención quirúrgica de reemplazo valvular cardíaco con circulación extracorpórea.
Material y métodos: Se diseñó un estudio prospectivo utilizando como muestra de veinticinco pacientes que fueron sometidos a un reemplazo valvular cardíaco con circulación extracorpórea. No hubo selección de los pacientes y sólo se excluyeron los pacientes que presentaron patología tiroidea y los que habían ingerido medicamentos con actividad tiroidea. Las tomas para la determinación de los niveles de la T4 Total se realizaron antes de la intervención, al final del tiempo de bomba durante la intervención, a la entrada de la UCI, a las 24 horas de la intervención y al quinto día de la misma. Para el estudio estadístico se utilizó la media, la desviación estándar y el test t de Student.
Resultados: Los niveles de la hormona T4 total presentó unos valores, antes de la intervención, de 80.28 ± 22.72, durante la intervención de 55.04 ± 17.37 con p = 0.0001, a la entrada en UCI de 65.20 ± 20.17 con p = 0.0006, a las 24 horas los valores fueron de 60.12 ± 20.30 con una significación de 0,0001. Al quinto día los valores medios fueron de 70.55 ± 30.68 con una probabilidad, con respecto a los iniciales, de p = 0.0506.
Conclusiones: En conclusión, los niveles de la hormona T4 total tienen un descenso importante a las 24 horas de una intervención de reemplazo valvular cardíaco con circulación extracorpórea y sólo logra recobrar las cifras normales al quinto día de la intervención.

2701
Abordaje xifoideo. Primera elección

Rizzardi JL, Concetti Cl, Meletti E, Benetti F
H. Español Rosario, IPAM. Rosario. Argentina

Introducción: Como alternativa del paro cardíaco inducido para la cirugía coronaria en la década del 80 se revitaliza la cirugía sin bomba, con importantes beneficios para los pacientes de alto riesgo-EPOC, I. renal, I. cerebral. A este trascendente paso le sigue otro para reducir aún más la reacción inflamatoria sistémica, como es la revascularización mínimamente invasiva. Esta tiene dos abordajes, toracotomía anterior y xifoidea, para lograr la revascularización de la arteria más importante, la descendente anterior (DA).
Objetivo: El presente trabajo plantea si puede considerarse al abordaje xifoideo como la primera elección ante una única revascularización coronaria.
Material y métodos: Se consideran 18 pacientes, 17 con revascularizaciones múltiples y 1 reoperación a DA, postoracotomía anterior.
Técnica: sección parcial del tercio inferior del esternón, en L invertida. Se diseca la arteria mamaria interna (MI) izquierda hasta el 2º espacio. En un paciente la MI fue arteria dadora de un puente venoso a la arteria diagonal. La anastomosis coronaria se realiza con corazón batiente, inmovilizando el septum con un estabilizador CTS.
Resultados: La evolución posoperatoria inmediata fue sin complicaciones. La alejada en 3 presentaron angina que revertieron 2 con tratamiento médico y el tercero con angioplastia a un puente venoso. La angiografía no reveló alteraciones en la MI y su anastomosis.
Conclusiones: Permite en una emergencia una rápida canulación y logra una adecuada revascularización de DA, diagonal y derecha. El obstáculo a considerar son las adherencias de ventrículo derecho al esternón ante una revascularización alejada. Este item inclina, ante una revascularización a DA, a pensar en la TA.

Tope

Sumario Analítico -

Index Revista - Index FAC

Publicación: Diciembre 2000

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