Mechanical support with microaxial blood pumps for postcardiotomy left ventricular failure: Can outcome be predicted?

Objective: We sought to identify the indications of mechanical support in p ostcardiotomy left ventricular failure in patients who are unable to underg o transplantation. Methods: From 1989 through 1997, 61 patients with postcardiotomy left ventr icular failure beyond intra-aortic balloon pumping were assisted with the H emopump cardiac assist system (Medtronic, Minneapolis, Minn). Their mean ag e was 64 +/- 8 years. Comorbidity was prevalent; 47% underwent cardiac mass age before pump support, and evolving myocardial infarction was diagnosed i n 43% before surgery. Multivariable logistic regression of data known at th e moment of pump insertion was performed to identify the risk Factors for m ortality. Results: Sixty-five percent of the patients were weaned from the device, bu t only 30% were discharged home. Cardiac index evolution during the first h ours after pump insertion (P <.001) is the only independent predictor for p ossibility to wean from the device in the multivariable analysis. Acute ren al failure is the only variable retained in the model fur 90-day mortality. Device-related complications were far more frequent with the femoral (54%) than with the transthoracic (6%) cannula. Only 13% of the patients had ble eding complications. Conclusions: One third of the patients with postcardiotomy heart failure re fractory to use of the intra-aortic balloon pump can be saved with the use of an endovascular axial now pump. Tt is impossible to predict lethal outco me on preoperative data alone. The early hemodynamic response to support se ems to be related to functional recovery of the heart and subsequent weanin g from the device.