Purpose: Development of aortic insufficiency (AI) in patients (pts) during continuous flow LVAD support is a well known phenomenon that can lead to ineffective LVAD output. Current literature reports an average AI progression by 0.7 grade at 6 months (mo). We hypothesized that optimal medical therapy (MT) together with lowering the LVAD speed to allow aortic valve (AV) opening delays development of significant AI. Methods and Materials: Charts and echocardiograms (echos) of 40 LVAD pts were reviewed for demographics and medications. Medications were uptitrated to MAP of 60-80mmHg. VAD speed (RPM) was reduced according to our outpatient VAD protocol and collected at 1 and 6 mo. Echos were reviewed at baseline (pre LVAD), 1 and 6 mo for left ventricular end diastolic dimensions (LVEDD)(cm), AV opening, presence/ absence of AI. AI was graded: O-none, 0.5-trace,1-mild,1.5-mild-moderate, 2-moderate, 2.5-moderate-severe, 3-severe. Results: Forty pts, mean age 58, were included in the study. At 6 mo 38/40 (93%) pts were receiving beta blocker (BB), 30/40 (73%) ACE-I/ARB, 27/40 (66%) aldosterone receptor blocker (ALDOBL). Fifty six percent of pts achieved half of maximal daily dose of ACE-I/ARB, 45% BB and 53% ALDOBL. Twenty nine out of 40 (71%) pts were on furosemide, mean dose 32 mg. At baseline mean LVEDD was 6.8, AI present in 12/40 pts (30%), mean grade 0.3. At 1 mo LVEDD decreased to a mean 5, AI present in 6/22 (27%) pts, mean grade 0.27. At 6 mo LVEDD was the same, mean 5.1, AI present in 8/19 (42%) pts. Mean grade increased from 0.27 to 0.4 (p 0.3). Mean LVAD speed at 1 mo was 9190 and decreased to 8840 at 6 mo (p 0.001). At 1 mo AV opened with every beat in 33% pts, partially opened in 8%, did not open in 54%. At 6 mo AV opened with every beat in 36% pts, partially opened in 21%, did not open in 43%. Conclusions: Our results suggest slower progression in the AI grade at 6 mo in LVAD pts, than reported to date. An early strategy of decreasing VAD speed combined with optimization of MT may account for this difference and possibly improve long term survival.