We evaluated the short-term safety and efficacy of using the TandemHeart(R) percutaneous ventricular assist device in high-risk patients undergoing aortic valvuloplasty procedures. Aortic valvuloplasty was performed in 4 patients who had no ventricular assist device support and in 7 patients who used the TandemHeart for hemodynamic support. The age range was 65 to 94 years (mean, 83 +/- 11 yr). The mean ejection fraction was 0.30 +/- 0.14. A transseptal antegrade approach to the aortic valve was used in 8 patients and a retrograde approach in the remaining 3. WITH THE TANDEMHEART, ALL PROCEDURES WERE TECHNICALLY SUCCESSFUL: each patient survived at least 1 month after the procedure. The mean total balloon inflation time was 37 +/- 10 sec. The aortic valve area was 0.6 +/- 0.1 cm(2) before the procedure and 0.9 +/- 0.2 cm(2) afterwards (P=0.006). Without TandemHeart support, 1 patient died of cardiac arrest during the procedure. The mean total balloon inflation time was 11 +/- 3 sec. Aortic valve area was 0.6 +/- 0 cm(2) before the procedure and 1.1 +/- 0.3 cm(2) afterwards (P=0.3). No patient developed aortic regurgitation. We conclude that use of the TandemHeart for hemodynamic support during high-risk aortic valvuloplasty is associated with favorable intraprocedural and short-term outcomes. With the TandemHeart in place, balloon placement was precise, and inflation was maintained for up to 45 sec without balloon displacement. These attributes are essential during stent-valve placement, are achieved without rapid ventricular pacing, and may reduce the risk of global ischemia and death.