Impact of Advanced Therapies for Improving Survival to Heart Transplant in Patients with Hypertrophic Cardiomyopathy.

Heart transplant has become an increasingly important option for patients with end-stage nonobstructive hypertrophic cardiomyopathy (HC). However, clinical details related specifically to the overall HC transplant experience remain sparse. We assessed outcomes of HC heart transplants, from 2002 to 2016, at Tufts Medical Center. Fifty-two nonobstructive severely symptomatic patients underwent evaluation at 47 ± 13 years; 11 (21%) declined or failed to qualify, most commonly because of co-morbidities (n = 7). Of the remaining 41 patients ultimately listed, 6 (15%) died of heart failure awaiting transplant (11%/year), 26 underwent transplant, and 9 remained active on the list. Survival rates on the waiting list depended on ≥1 treatment intervention: inotropic medications (n = 20), ventricular assist devices (n = 7), or implantable defibrillators terminating ventricular tachyarrhythmias (n = 7). Of the 26 transplanted patients, 24 survived for 4.8 ± 3.4 years (up to 12), including 23 who are currently alive. The survival rate 5 years post transplant is 92%. Compared with heart transplants for other cardiomyopathies, patients with HC had similar mortality while wait-listed and post transplant (p = 0.77 and 0.13, respectively). In conclusion, a large proportion of patients with HC considered for transplant ultimately received hearts and experienced excellent short- and long-term survival rates. The survival rate on the waiting list was directly attributable to major interventions: implantable cardioverter-defibrillators, inotropic drugs, and ventricular assist devices, and the perception that patients with HC have low wait-list mortality risk does not appear justified. Neither normal ejection fraction nor peak oxygen consumption > 14 ml/kg/min should exclude drug refractory severely symptomatic patients with HC from heart transplant consideration.

Diagnostic and prognostic value of myocardial blood flow quantification as non-invasive indicator of cardiac allograft vasculopathy.

Aims: Cardiac allograft vasculopathy (CAV) is a leading cause of death in orthotopic heart transplant (OHT) survivors. Effective non-invasive screening methods are needed. Our aim was to investigate the added diagnostic and prognostic value of myocardial blood flow (MBF) to standard myocardial perfusion imaging (MPI) with positron emission tomography (PET) for CAV detection. Methods and results: We studied 94 OHT recipients (prognostic cohort), including 66 who underwent invasive coronary angiography and PET within 1 year (diagnostic cohort). The ISHLT classification was used as standard definition for CAV. Positron emission tomography evaluation included semiquantitative MPI, quantitative MBF (mL/min/g), and left ventricular ejection fraction (LVEF). A PET CAV severity score (on a scale of 0-3) was modelled on the ISHLT criteria. Patients were followed for a median of 2.3 years for the occurrence of major adverse events (death, re-transplantation, acute coronary syndrome, and hospitalization for heart failure). Sensitivity, specificity, positive, and negative predictive value of semiquantitative PET perfusion alone for detecting moderate-severe CAV were 83% [52-98], 82% [69-91], 50% [27-73], and 96% [85-99], respectively {receiver operating characteristic (ROC area: 0.82 [0.70-0.95])}. These values improved to 83% [52-98], 93% [82-98], 71% [42-92], and 96% [97-99], respectively, when LVEF and stress MBF were added (ROC area: 0.88 [0.76-0.99]; P = 0.01). There were 20 major adverse events during follow-up. The annualized event rate was 5%, 9%, and 25% in patients with normal, mildly, and moderate-to-severely abnormal PET CAV grading (P < 0.001), respectively. Conclusion: Multiparametric cardiac PET evaluation including quantification of MBF provides improved detection and gradation of CAV severity over standard myocardial perfusion assessment and is predictive of major adverse events.

Socioeconomic position, ethnicity, and outcomes in heart transplant recipients.

The purpose of the present study was to assess whether a low socioeconomic (SE) position is associated with outcomes in heart transplant recipients. We used the US Census 2000 database to derive a summary SE score for 520 patients who had undergone underwent a first heart transplant at 1 of 4 Boston hospitals during 1996 to 2005 and compared the outcomes in the lowest quartile SE group (n = 129) to those for the remaining patients (n = 391). The low SE group and controls were similar with respect to cardiac diagnosis, hemodynamic support, listing status, year of transplant, and initial immune suppression. Low SE patients were more likely to be nonwhite. Graft loss occurred in 142 patients (135 deaths and 7 repeat transplants). Hospital mortality after transplantation was not associated with race/ethnicity or low SE position. In patients who survived the transplant hospitalization, nonwhite ethnicity (hazard ratio 1.8, 95% confidence interval 1.1 to 2.9) and low SE group (hazard ratio 1.7, 95% confidence interval 1.1 to 2.5) were associated with a greater risk of subsequent graft loss. In the adjusted analysis, the risk of graft loss remained greater for both nonwhite race/ethnicity (hazard ratio 1.7, 95% confidence interval 1.0 to 2.9) and low SE position (hazard ratio 1.5, 95% confidence interval 1.0 to 2.4). Rejection episodes were more frequent in nonwhite transplant recipients and in those in the low SE group. In conclusion, among heart transplant recipients who survive the transplant hospitalization, nonwhite recipients and those in a low SE position are at greater risk of rejection and graft loss.