Volume 7 - Número 2

Between January 1979 and January 1992, 1071 coronary bypass graft reoperations were performed at the Heart Institute and Beneficencia Portuguesa Hospital. Of these, 1015 were reoperated upon once, 53 twice and 3 three times. The surgeries were due to spread of coronary atherosclerosis in 117 patients (10.9%), partial or total graft occlusion in 183 (17.1%), combination of the prior factors in 728 (67.9%), technical problems in 21 (1.9%), and others in 22 (2.1%). The patients ages varied from 34 to 84 years (mean 61.6), predominantly male (86.1%) and Caucasian (96.5%). The period between the first and second operations varied from the same day to 22 years after (mean 9,3%), the second and third from one to 11 years (mean 8.0) and between the third and fourth seven to nine years (mean 7.7). During the surgical procedures: one mammary artery in 610 (56.9%) cases, both mammary arteries in 192 (17.9%), gastroepiploic arteries in six (0.6%) and epigastric arteries in five (0.5%) were used. In 813 (75.9%) of the 1071 reoperations at least one arterial graft was employed in the coronary bypass grafts. There were 87 (8.1%) hospital deaths in this period, of which 39 (44.8%) were directly related to ventricle dysfunction, and 48 (55.2%) caused by other complications: pulmonary 22, sepsis 8, coagulation 7, neurologic 6 and mesenteric ischemia 5. The principal factors associated to mortality were: I) preoperative risk factors were: diabetes, hypertension, high colesterol, obesity, smoking, hereditary history, etc.; 731 patients presented up to two risk factors with 35 deaths (4.8%); 299 presented three or four with 38 (12.7%) deaths and in 4 patients there were five or more risk factors, with 14 (34.1 %) deaths; 2) preoperative functional class: 317 were in class I or II, 11 (3.5%) of which died; 449 were in class III, 39 (8.7%) having died; and 305 in class IV with 46 (15.1%) deaths. Triarterial vessels compromised associated or not to main trunk lesion: 788 presented this complication, of which 74 (9.4%) died. Among 283 characterized by uni or biarterial lesions, 13 (4.3%) having died; 3) surgery status: 110 emergency operations with 35 deaths (31.8%), 961 elective surgeries 52 (5.4%) having died. In the last two years, however, 379 coronary bypass graft reoperations were performed with only 13 deaths (3.5%). This decreased in mortality in relation to the preceding years was attributed, among other factors, to the improved methods of myocardial protection, especially in patients with worse ventricle condition. It was also emphasized in the last two years the arterial graft usage in the reoperations. Mean usage of at least one arterial graft in the reoperations was 82.2%. It is strongly believed that the best results can be reached through adequate surgical handling, increased employment of the arterial graft and especially avoiding emergency situations by earlier reoperation. Keywords: myocardial revascularization, reoperation

From September 1988 to July 1990, 56 patients under 20 years of age (mean 12.7 ± 5.12 years) with pure or predominant mitral valve regurgitation secondary to rheumatic valve disease, underwent mitral valvuloplasty. Ninety-three percent of the patients were in functional class III ou IV (NYHA). The basic surgical technique used in all patients was a modified measured assy metric anuloplasty which was associated in 69.7% of the cases with another plastic procedure. Intraoperative echodopplercardiography was always used and showed a good correlation with the postoperatoty echo studies, with 64% of the patients free from residual lesions. There was no hospitalar mortality. Fifty-three (94.6%) patients were followed from 1 to 40 months (mean 16.3%). There was one sudden death 3 months after the operation. Four patients were reoperated upon, 3 of whom due to recurrent rheumatic carditis. The remainder are in functional class I or II (NYHA). We conclude based on these early results that assymetric mitral anuloplasty is an excellent procedure for young patients with rheumatic heart disease, being a good alternative to valve replacement or ring implantations. Keywords: mitral valve, surgery; rheumatic heart disease, mitral valvuloplasty; mitral valve, rheumatic heart disease

From August 1989 to February 1992, 32 patients underwent vascular reconstructions using crimped bovine pericardial conduits processed in glutaraldehyde. The introduction of the crimping process used for synthetic vascular prosthesis provided circular tubes, which retain their shape with bending and avoid kinking. Twenty-nine patients (Group I) presented vascular lesions involving the thoracic and/or abdominal aorta, including aneurysms, acute dissections, coarctation and aorto-iliac lesion. The thoracic aortic reconstruction was performed in 25 patients, including aortic valve replacement in 10, the abdominal aorta in 2, and the aortic bifurcation in 2. Three patients (Group II) with complex congenital heart lesions underwent reconstruction of the right ventricular outflow tract in 2, and the Fontan operation in 1. Hospital mortality in Group I was 24% (7 patients). Causes of death were low cardiac output in 4, recurrence of aortic dissection in 2 and respiratory infection in 1. Six of them had been operated upon as emergencies due to acute aortic dissection. All patients in group II survived the operation. There was 1 late death in group I due to methabolic complications related to diabetes and chronic renal failure. This initial clinical experience showed a mean follow-up of 16 months per patient and the longest follow-up was 32 months. It was not observed any late complication related to the crimped bovine pericardial conduit up-to-date. Keywords: arterial prosthesis; vascular prosthesis; aneurysms, aortic, surgery

From September 1991 to February 1992, nine patients presenting thoracic aorta pathologies were submitted to surgery using deep hypothermic total circulatory arrest with retrograde cerebral perfusion. Six patients were male and three female, with ages ranging from 45 to 80 years. Four had type A dissection, three had true aorta aneurysm, one had true aneurysm associated with type A dissection and one had anulusaorta ectasia associated with type B dissection. A cava-cava-femoral cardiopulmonary bypass was established with deep hypothermia and total circulatory arrest. Retrograde blood cardioplegia was used for myocardial preservation. During total circulatory arrest retrograde cerebral perfusion was made using arterial line cannulated to the superior vena cava with a flow of 250 to 300 ml/min the central venous pressure monitored at the arm ranged between 30 and 40 cmH2O. Surgical repair was achieved using bovine pericardial tube and patch associated to the biological glue. Duration of cardiopulmonary bypass ranged from 75 to 169 min, total circulatory arrest from 32 to 79 min and retrograde cerebral perfusion from 32 to 79 min. There was no mortality associated to surgery or to immediate postoperative period. There was only one late death, due to septcemia. All other patients are on follow-up. The results show that total circulatory arrest with retrograde cerebral perfusion protects the brain more effectively than conventional total circulatory arrest during surgical treatment of thoracic aorta pathologies that require total circulatory arrest. Keywords: aneurysms, aortic, surgery; cerebral protection

The "maze" procedure for surgical treatment of chronic atrial fibrillation (AF) described by Cox was performed in 9 patients from July 91 to May 92; 7 were female and the ages range from 37 to 63y (51,4y). Eight patients had surgical rheumatic valve disfunction (mitral stenosis in 6; mitral double disfunction in 2 being 1 with associated tricuspid regurgitation) and 1 had recurrent paroxicistic AF with no valve disfunction. Surgical treatment was performed following the technique described by Cox and the surgery was completed with 6 mitral comissurotomies and 2 mitral valve replacements. Three patients had left atrial thrombosis. There were no immediate deaths and 1 patient died in the 45th day with infeccious complications. The first patient required reoperation for bleeding review. Second and 3rd patients presented transitory atrial tachycardia in 3rd and 5th day, controlled with intravenous amiodarone. No other complications were observed. In a mean follow up period of 5,4m (1 to 10 m), all patients were in regular atrial rhythm without antiarrhythmic drugs. Effective atrial contraction was demonstrated by ECHO in all patients and no one returned to AF. In conclusion, this initial follow up showed good results in rheumatic AF and more clinical observation is necessary to a definitive evaluation. Keywords: atrial fibrilation, surgery; "maze" procedure

Clinical results with the use of porcine bioprosthesis are satisfactory from the standpoint of hemodynamic performance, low incidence of thromboembolysm providing adequate quality of life. Calcification and tissue tear remain the major complications of bioprosthesis , mainly in children and young patients. Several stratergies were proposed to control or even to avoid calcification; up to the present, none of them have proved to decrease calcification or to prolong their durability. This controlled clinical study was undertaken based upon the quality of anticalcificant effect of the P.S. treatment obtained in animal implants with the Biocor porcine bioprosthesis; the negative results of toxicological analysis of the treated tissue and the good performance in fatigue testing of the P.S. treated Biocor bioprosthesis. The rational of the P.S. treatment is to obtain covalent bounds of the anticalcificant agent to the tissue, in more durable form. From February/1991 to March/1992, 66 treated bioprosthesis were implanted in 55 patients; there were 28 males and 27 femeles. The age ranged from 11 to 68 years. There were 72.7 ± 11.8 of patients below 30 years of age. Mean age was 26.6. Rheumatic heart disease was the etiological factor in 70.9% ± 12.0. Regular sinus rhythm was present in 70.9%. Preoperative functional class was 40.0% ± 12.0 and 52.7% ± 13.2 respectively, for class III and IV of the NYHA; 55 patients underwent valve replacement namely aortic in 16 patients (29.1% ± 12.0); mitral, 28 patients (50.1% ± 13.21) and double valve replacement 11 patients (20.0% ± 10.6). The surgical technique was the conventional, using bouble oxygenator, crystaloid cardioplegia and U type sutures. There were no complications related to the new bioprosthesis. Hospital mortality was 2 in 55 patients or 3.6%. The majority of the 53 patients are in class functional I and II. The follow up is being done quaterly by clinical, echodopplercardiographical and laboratorial tests (hematological and biochemistry). During this period of 13 months, there were no complications related to the newly treated bioprosthesis. Keywords: heart valves prostheses, surgery; heart valves, surgery

The standard surgical treatment of the supravalvar aortic stenosis is characterized by the ampliation of one or more sinus of Valsalva utilizing patch of prosthetic material (Dacron, bovine pericardium) with or without transsection of the aorta. One possible limitation on late results with these procedures is the fact of graft thickening or calcification, difficulting the aortic root growing, mainly when the patient is a child. In order to avoid this complication, we propose a new technical modification that effectivelly increases the aortic diameter, without the use of prosthetic material, using only the normal ascending aortic wall to reconstruct and enlarge the stenotic area. We performed this procedure in 4 patients with ages ranging from 23 months to 38 years old (m - 14, 5, Y. O,), weighing from 10 to 56 kg (m - 26,2 kg). The three young patients had sings of Williams syndrome. The gradients between left ventricle and aorta were 50, 70, 100 and 100 mmHg. Cristaloid cardioplegia was infunded antegrately. The ascending aorta was entirely mobilized. After aortic transsection immediately above the stenotic point, we made vertical incisions from the free edge to the botton of the Valsalva sinuses. Sometimes the size and position of the left coronary ostium impedes the incision on the left Valsalva sinus. On the distal aorta we made three longitudinal incisions in the position corresponding to the comissures of the aortic valve. Suturing these two parts we reconstructed the aortic root anatomicaly. The four patients had uneventful hospitalization and were discharged in good clinical condition. With a follow-up from 1 to 6 months, all the patients are assymptomatic. Keywords: supravalvar aortic stenosis, surgery; heart valve, aortic, surgery

Dynamic cardiomyoplasty improves left ventricular function and survival of patients with severe cardiomyopathies. The purpose of this study was to investigate the factors influencing cardiomyoplasty results in 22 patients operated upon at the Heart Institute. All patients were in New York Heart Association class III or IV, despite the use of maximal medical therapy. Eighteen patients had idiopathic dilated cardiomyopathy, in two patients the cardiomyopathy was due to Chagas' disease and in two due to ischemic ethiology. There were no operative death and patients were followed up for a mean of 20.5 months. Nine patients died at late follow-up period, and actuarial survival rates were 76.1% at 1 year and 63.8% at 2 years of follow-up. Six patients are presently in functional class I and six in class II. The mortality and the absence of functional improvement at 1 year were associated to episodes of pulmonary thromboelbolysm and to heart failure progression in patients with severe muscle flap ischemic compromise at the immediate postoperative period (creatinokinase peak level > 14001. U.) (p=0.03). In addition, the improvement of left ventricular ejection fraction at 6 months of follow-up was more significant in patients who presented lower values of creatinokinase after the surgical procedure (p=0.02). Otherwise, the influence of left ventricular dimension on ejection fraction changes was documented only when patients with severe muscle flap compromise were withdrawn from the analysis (p=0.06). Despite the absence of functional class influence on 1 year results of cardiomyoplasty, patients operated upon in class IV presented a less significant survival than patients operated upon in class III at 2 years of follow-up (33.3% versus 78.1 %, p= 0.04). In conclusion, quality of life and left ventricular function improvement after cardiomyoplasty may be limited by muscle flap ischemic compromise. Patient's condition prior to surgery and the degree of left ventricular dilation may also influence cardiomyoplasty results in patients with severe cardiomyopathies. Keywords: cardiomyoplasty; cardiomyopathies, surgery

From January 1987 to January 1992,105 patients (64 males; age x 35.7 years) were referred to surgery due to valvar edocarditis. Forty-five patients had the aortic valve involved (32 in the native valve and 12 in a prosthesis previously implanted (6 metalic and 6 biological and 1 case of previous valve suture). Twelve patients needed removal of abscess on the valve which was compromising the valvar ring and contiguous structures. Endocarditis in the mitral valve was treated in 34 patients (18 in native valve and 16 in artificial prosthesis). In such patients we performed 2 sutures of the valves and implanted 24 biological and 8 metalic valves. Involvement of both mitral and aortic apparatus, was present in 18 cases. In such patients, 11 received biological prosthesis in mitral position, and metalic prosthesis in aortic position. One of these cases, that presented an abscess in both mitral and aortic valve, received a single patch of bovinum pericardium and the prosthesis were partially implanted in such patch. The remained 8 cases presented endocarditis in congenital heart disease (6 cases), in pacemaker electrode (1 case) and 1 case in the 3 valves (aortic, mitral and tricuspid). The in-hosipital mortality rate was: 18% (23.5% to mitral; 15.5% to aortic and 16.6% to mitral-aortic valves endocarditis). We concluded that surgery for endocarditis has improved the results, mainly after surgeons became more aggressive pulling out the infected tissue with great resections and correcting the additional deffects, in an attempt to restore the heart integrity and valvular function. Keywords: endocarditis, infective, surgery

Fifty two patients with primary cardiac tumors were operated on at the Instituto Dante Pazzanese de Cardiologia between 1962 and 1991. Among the benign neoplasms, 43 were myxomas; the only two malignant tumors were rhabdomyosarcomas. The mean age of the patients was 41 years (range 15 days to 68 years); 33 patients were females and 19 males; 52.6% had congestive heart failure, 18% had chest pain or palpitation and 16% taquiarrhythmias. Complete resection was carried out in 50 patients. The two patients with malignant tumors had only been submitted to biopsy. All patients survived operation, although 3 died in the early postoperative period. One patient with myxoma presented recurrence three years after the innitial surgery and was reoperated on. The follow up data of 20 patients are available, all in NYHA functional class I. Longterm results were excellent in this group. Keywords: heart tumors, surgery