Prolonged corrected QT interval in the donor heart: Is there a risk?

Background: Assessing the QT interval in donors is important to exclude long QT syndrome as the cause of death. A donor heart with a corrected QT (QT ) >500 milliseconds is often concerning. We sought to evaluate first year outcomes for donors with a QTc interval >500 milliseconds.

Methods: Between 2010 and 2014, we assessed 257 donor hearts for QT interval >500 milliseconds. Post-transplant outcomes included 1-year survival, 1-year freedom from any-treated rejection, 1-year freedom from cardiac allograft vasculopathy (CAV) defined as stenosis ≥30% by angiography, and 1-year freedom from nonfatal major adverse cardiac events.

Results: Patients with QT interval >500 milliseconds had a significantly lower 1-year freedom from CAV development. There were no significant differences for other outcomes. A significantly higher percentage of donors with QT >500 milliseconds had a stroke or subarachnoid hemorrhage. Multivariate analysis found that donor QT >500 milliseconds was associated with a 6.7-fold increased risk of developing CAV (P=.029, 95% CI 1.21-36.6) after adjusting for other known risk factors.

Conclusion: QT >500 milliseconds in the donor heart appears to be an independent risk factor for the development of early CAV after heart transplantation possibly due to a higher immunological risk.