The Association Between Pre-Transplant PVR and Post-Transplant Outcomes Differs by LVAD Status

Abstract

<h3>Purpose</h3> Elevated pulmonary vascular resistance (PVR) is a risk factor for mortality after heart transplantation (HT), but whether this association differs for patients with and without LVAD support prior to HT is unknown. <h3>Methods</h3> We analyzed adult first-time HT recipients from the UNOS registry transplanted between 2010 and 2019. As our prior work using the STS-INTERMACS registry established an association between PVR > 1.5 WU and poor outcomes in LVAD recipients, we quantified the independent associations between PVR > 1.5 WU and the outcomes of 30-day graft failure and 1 year mortality using multivariable logistic regression, stratified by LVAD support status at the time of HT. We also examined the association with 10-year survival using multivariable Cox proportional hazards regression. <h3>Results</h3> Among 18913 HT recipients, 9286 (49%) had an LVAD at the time of HT. 6101 (66%) of HT recipients bridged with LVADs had PVR > 1.5 WU at the time of HT, compared with 7114 of 9627 (74%) patients without LVADs. When adjusted for age, waitlist status, creatinine, donor ischemic time, and other important variables, pre-transplant PVR > 1.5 WU was associated with a higher risk of 30-day graft failure (OR 1.28, 95% CI 1.06-1.53, p=0.009, Figure). This risk was limited to patients supported with LVADs at the time of HT (with LVAD OR 1.53, 95% CI 1.21-1.95 vs without LVAD OR 0.96, 95% CI 0.72-1.28, interaction p=0.014). Similar findings were seen for 1 year mortality, though the interaction between LVAD support and PVR was not statistically significant (Figure). PVR > 1.5 WU was not significantly associated with 10-year survival (HR 1.07, 95% CI 1.0-1.15, p=0.053). <h3>Conclusion</h3> The clinical significance of pre-transplant PVR is different for LVAD and non-LVAD bridged HT recipients. HT recipients bridged with LVADs have an increased risk of poor outcomes even with conventionally acceptable PVR values. Whether more aggressive reduction of PVR among HT candidates supported with LVADs can mitigate these risks requires further study.