UCLA

BACKGROUND: Evidence on the comparative outcomes following percutaneous microaxial ventricular assist devices (pVAD) versus intra-aortic balloon pump for nonacute myocardial infarction cardiogenic shock is limited. METHODS AND RESULTS: We included 704 and 2140 Medicare fee-for-service beneficiaries aged 65 to 99 years treated with pVAD and intra-aortic balloon pump, respectively, for nonacute myocardial infarction cardiogenic shock from 2016 to 2020. Patients treated using pVAD compared with those treated using intra-aortic balloon pump were more likely to be concurrently treated with mechanical ventilation, renal replacement therapy, and blood transfusions. We computed propensity scores for undergoing pVAD using patient- and hospital-level factors and performed a matching weight analysis. The use of pVAD was associated with higher 30-day mortality (adjusted odds ratio, 1.92 [95% CI, 1.59-2.33]) but not associated with in-hospital bleeding (adjusted odds ratio, 1.00 [95% CI, 0.81-1.24]), stroke (adjusted odds ratio, 0.91 [95% CI, 0.56-1.47]), sepsis (OR, 0.91 [95% CI, 0.64-1.28]), and length of hospital stay (adjusted mean difference, +0.4 days [95% CI, -1.4 to +2.3]). A quasi-experimental instrumental variable analysis using the cross-sectional institutional practice preferences showed similar patterns, though not statistically significant (adjusted odds ratio, 1.38; 95% CI, 0.28-6.89). CONCLUSIONS: Our investigation using the national sample of Medicare beneficiaries showed that the use of pVAD compared with intra-aortic balloon pump was associated with higher mortality in patients with nonacute myocardial infarction cardiogenic shock. Providers should be cautious about the use of pVAD for nonacute myocardial infarction cardiogenic shock, while adequately powered high-quality randomized controlled trials are warranted to determine the clinical effects of pVAD.