Evolution of Status 1A Heart Transplant Candidates

As ventricular assist device (VAD) use has increased and patient survival has improved, VAD patients have formed an increasing proportion of the heart transplant (HT) waiting list, especially among those in Status 1A. Given improved technology and management protocols, they are living longer and are thus shifting the wait list landscape. We sought to better understand the trends among these Status 1A VAD patients. Data from the UNOS registry for patients listed for HT from 1999 - 2013 were analyzed. Patients were grouped based on the year they were listed (1999-2003, 2004-2008, vs 2009-2013). Statistical analyses were performed using Chi-squared tests, and wait time-to-transplant analysis was performed using Kaplan-Meier analysis, censoring for delisting other than transplant. Status 1A patients represent an increasing proportion of the waiting list (14.1%, 32.1%, and 39.4%, respectively; p<0.001), and more patients are being transplanted at Status 1A (35.4%, 42.3%, 59.3%; p<0.001). More candidates are using up their 30 days of VAD Status 1A time prior to HT (3.4%, 5.9%, 10.2%, respectively; p<0.001). Between the more recent two time periods, VAD patients who eventually were transplanted were almost 50% more likely to have a device issue (thrombosis, malfunction, infection, etc) qualifying them as Status 1A (13.1% vs 18.6%, p<0.001), while qualifying as Status 1A under their 30-day allowance at time of HT decreased from 29.4% to 24.4% (p<0.001). The Kaplan-Meier estimated median wait times for HT have increased from 57 days to 111 days over these time periods (see figure, p<0.001). As wait times have increased among Status 1A patients, VAD patients are being transplanted less frequently during their 30-day allowance period. As such, Status 1A classification via worsening clinical status even on VAD support and/or a device issue is unfortunately what many must wait for before they can proceed to HT.