Clinical predictors of prosthesis-patient mismatch after aortic valve replacement for aortic stenosis

OBJECTIVE: We sought to ascertain predictors of Patient Prosthesis Mismatch, an independent predictor of mortality, in patients with aortic stenosis using bioprosthetic valves. METHOD: We analyzed 2,107 sequential surgeries. Patient Prosthesis Mismatch was calculated using the effective orifice area of the prosthesis divided by the patient's body surface area. We defined nonsignificant, moderate, and severe Patient Prosthesis Mismatch as effective orifice area indexes of .0.85 cm²/m, 0.85-0.66 cm²/m², and <0.65 cm²/m², respectively. RESULTS: A total of 311 bioprosthetic patients were identified. The incidence of nonsignificant, moderate, and severe Patient Prosthesis Mismatch was 41 percent, 42, and 16 percent, respectively. Severe Patient Prosthesis Mismatch was significantly more prevalent in females (82 percent). In severe Patient Prosthesis Mismatch, the perfusion and the crossclamp times were considerably lower when compared with nonsignificant Patient Prosthesis Mismatch and moderate Patient Prosthesis Mismatch. Patients with severe Patient Prosthesis Mismatch had a significantly higher likelihood of spending time in the intensive care unit and a significantly longer length of stay in the hospital. Body surface area was not different in severe Patient Prosthesis Mismatch when compared with nonsignificant Patient Prosthesis Mismatch. In-hospital mortality in patients with nonsignificant, moderate, and severe Patient Prosthesis Mismatch was 2.3 percent, 6.1 percent, and 8 percent, respectively. Minimally invasive surgery was significantly associated with moderate Patient Prosthesis Mismatch in 49 percent of the patients, but not with severe Patient Prosthesis Mismatch. CONCLUSION: Severe Patient Prosthesis Mismatch is more common in females, but not in those with minimal available body surface area. Though operative times were shorter in these patients, intensive care unit and hospital lengths of stay were longer. Surgeons and cardiologists should be cognizant of these clinical predictors and complications prior to valve surgery.

Efeito do captopril na dilataçäo ventricular progressiva após infarto do miocárdio anterior / Effect of captopril on progressive ventricular dilatation after anterior myocardial infarction

Realizamos estudo duplo-cego, comparativo com placebo para determinar se a dilataçäo ventricular continua durante a fase de convalescença após infarto do miocárdio e se a terapêutica com captopril altera esse processo. Cinqüenta e nove pacientes com primeiro infarto do miocárdio anterior e fraçäo de ejeçäo de 45 por cento ou menos se submeteram a cateterismo 11 e 31 dias depois do infarto, se näo estivessem em insuficiência cardiáca congestiva evidente. Foram entäo randomicamente alocados para placebo ou captopril e acompanhados por um ano. Repetiu-se a cateterizaçäo para avaliar as mudanças intervalares na funçäo hemodinâmica e volume ventricular esquerdo. Trinta e oito pacientes masculinos foram avaliados, a cada três meses, para prova de exercício máximo em esteira. Näo foram detectadas diferenças na situaçäo basal em relaçäo às variáveis clínicas, hemodinâmicas ou de ventriculografia quantitativa. Durante um ano de acompanhamento o volume distólico final do ventrículo esquerdo aumentou em média (ñ DP) de 21 ñ 8ml (P < 0,02) no grupo placebo, mas somente 10 ñ 6ml (P näo significante) no grupo captopril. A pressäo de enchimento ventricular esquerda permaneceu elevada com placebo mas diminuiu (P < 0,01) de 36 pacientes que era de alto risco para dilataçäo ventricular, por terem uma oclusäo persistente da artéria coronária anterior esquerda, captopril preveniu dilataçöes ventriculares futuras (P < 0,05). Pacientes que receberam captopril tambem tiveram aumento na capacidade de exercício (P < 0,05). Este estudo preliminar indica que após infarto anterior do miocárdio, a dilataçäo ventricular é progressiva e captopril pode atenuar esse processo, reduzir as pressöes de enchimento, e melhorar a tolerância ao exercício