Tratamento cirúrgico da rotura do septo interventricular pós infarto agudo do miocárdio Surgical treatment of ventricular septal defect post acute myocardial infart

Abstract

A rotura do septo interventricular (RSI) reduz a perspectiva de sobrevida do paciente com infarto agudo do miocárdio (IAM). Entre 1968 e 1987, atendemos 48 pacientes (p) com este diagnóstico, sendo 16 (33%) mantidos clinicamente e 32 (67%) submetidos a cirurgia. Todos os p clínicos faleceram durante a internação. Dentre os p operados, o IAM se localizava na parede anterior em 18 (56%) e na inferior em 14 (44%), com mortalidades respectivas de 6 (33%) e 4 (29%). Disfunção ventricular esquerda severa (Killip III e IV) foi encontrada em 26 (81%). Em 18 (56%) p foi introduzido o cateter de Swan-Ganz. Dos 31 (97%) p que se submeteram a cinecoronariografia, 22 (71%) apresentavam lesão uniarterial e 9 (29%), doença multiarterial. Entre os p com lesões isoladas, a descendente anterior foi acometida em 15 (68%), a coronária direita em 6 (27%) e a circunflexa em 1 (5%). A cirurgia foi realizada nas 2 primeiras semanas de evolução em 8 (25%) e, após este período, em 24 (75%), com mortalidades de 6 (75%) e 4 (17%), respectivamente. O balão intra-aórtico foi usado em 7 (22%). Os procedimentos cirúrgicos associados ao fechamento da RSI foram revascularização miocárdica em 10 (31%), aneurismectomia de VE em 17 (53%) e infartectomia e 6 (19%). Na evolução tardia, dos 22 sobreviventes, 14 (64%) encontram-se assintomáticos, 1 (5%) sintomático, ocorreram 4 (18%) óbitos e perdeu-se a evolução de 3 (13%). Concluímos que, apesar do risco cirúrgico, a cirurgia precoce ainda é a melhor opção terapêutica desta complicação.The ventricular septal rupture (VSR) following acute myocardial infarction (AMI) is a rare and catasthrophic complication with a high mortality rate. Surgery is the only effective procedure to try to control this complication. However the surgical mortality is elevated and is closely related to the post-infarct period thus making the indication for the precise time for surgery one the fundamental aspects for its success. In a population of 48 patients with diagnosis of VSD following AMI, according to the criteria of the Myocardial Infarction Research United, we treated 32 (67%) with surgery. The diagnosis was confirmed by hemodynamic in all patients. The AMI was anterior in 18 cases (56%) and inferior in 14 (44%); the mortality rate is 6 (33%) and 4 (29%) cases respectively. Severe heart failure (Killip III and IV) was present in 26 cases (81%) and life threatening arrhythmias in 13 (41%). A Swan-Ganz catheter was introduced at bedside in 18 (56%) patients to confirm the diagnosis and provide a better therapeutic management. Angiographic studies were performed in 31 (97%). Cineangiography showed a critical lesion (obstruction equal or greater than 70% of the lumen) in one vessel in 22 patients (71%): left anterior descending coronary artery in 15 (68%), right coronary artery in 6 (27%) and left circunflex in 1 (5%). Nine cases (29%) had critical lesions in two vessels. The pulmonary artery pressure was always elevated in those patients in whom the pressure was measured. Clinical treatment was used in 16 (33%) cases and all died during hospitalization. Eight patients (25%) underwent the surgery within the first two weeks and 24 (75%) after this period; mortality rate was 6 (75%) and 4 (17%) cases respectively. Nine patients were re-catheterized in the post operative period and only one presented signs of significant shunt in the ventricular level. This patient who was the oldest of the group was reoperated later. Of the 22 patients discharged from the hospital 15 are long-term survivors. In 3 the follow-up was lost and 4 died. The accumulated data allows us to conclude that: 1) the attempt to postpone surgery by keeping the patients under medical treatment waiting for a more favorable time for surgery did not produce satisfactory results; 2) surgery should be performed in the acute phase (first two weeks) in spite of a still elevated mortality in this group; 3) after the first two weeks the results are good with low mortality rate for this kind of surgery; 4) VSD reappearence was infrequent.

Keywords

• septo interventricular, rotura
• infarto do miocárdio
• ventricular septal defect
• myocardial infarct