The development of aortic insufficiency in left ventricular assist device-supported patients.

BACKGROUND

Aortic insufficiency (AI) following left ventricular assist device (LVAD) placement can affect device performance. The aim of this study was to examine AI development following LVAD implantation.

METHODS AND

RESULTS

Echocardiograms (n=315) from 78 subjects undergoing HeartMate-XVE (n=25 [32%]) or HeartMate-II (n=53 [68%]) implantations from 2004 to 2008 were reviewed. Studies were obtained preoperatively and at 1, 3, 6, 12, 18, and 24 months after surgery. AI was graded on an interval scale (0=none, 0.5=trivial, 1=mild, 1.5=mild-moderate, 2=moderate, 2.5=moderate-severe, 3=severe), and the change in AI at follow-up was analyzed with significance tests. Kaplan-Meier estimates for freedom from moderate or worse AI at follow-up were generated. Mixed-model linear regression was used to identify correlates of AI progression during LVAD support. The median (25th, 75th percentile) duration of LVAD support was 239 (112, 455) days, and preoperative AI grade was 0.0 (0.0, 0.0). At 6 months, 89±4% of subjects (n=49 at risk) were free from moderate or worse AI, but this was reduced to 74±7% (n=29 at risk) and 49±13% (n=13 at risk) by 12 and 18 months, respectively. Correlates (slope±SE) of AI progression included female sex (0.002±0.001; P=0.01), smaller body surface area (-0.003±0.001 per m(2); P=0.0017), and HeartMate-II model type (0.002±0.001; P=0.039). Correlates (β±SE) of progressive AI on postoperative echocardiogram included increasing aortic sinus diameter (0.04±0.01 per mm; P=0.001), an aortic valve that remained closed (0.42±0.06; P<0.001) or only intermittently opened (0.34±0.09; P<0.001), and lower left ventricular diastolic (-0.002±0.0004 per cm(3); P<0.001) and systolic (-0.002±0.0004 per cm(3); P<0.001) volumes.

CONCLUSIONS

AI progresses over time in LVAD-supported patients. As we move toward an era of long-term cardiac support, more studies are needed to determine the clinical significance of these findings.