Invasive Assessment of Coronary Physiology Predicts Late Mortality After Heart Transplantation
Background—The aim of this study is to determine the prognostic value of invasively assessing coronary physiology early after heart transplantation.
Methods and Results—Seventy-four cardiac transplant recipients had fractional flow reserve (FFR), coronary flow reserve (CFR), the index of microcirculatory resistance (IMR) and intravascular ultrasound (IVUS) performed down the left anterior descending coronary artery soon after (baseline) and 1 year after heart transplantation. The primary endpoint was the cumulative survival free of death or retransplantation at a mean follow-up of 4.5±3.5 years. The cumulative event-free survival was significantly lower in patients with an FFR<0.90 at baseline (42 vs 79%, p=0.01) or an IMR≥20 measured one year after heart transplantation (39 vs. 69%, p=0.03). Patients in whom IMR decreased or did not change from baseline to 1 year had higher event-free survival compared to those patients with an increase in IMR (66 vs. 36%, p=0.03). FFR<0.90 at baseline (hazards ratio [HR] 0.13, 95% confidence interval [CI] 0.02-0.81, p=0.03), IMR ≥20 at 1 year (HR 3.93, 95% CI 1.08-14.27, p=0.04) and rejection during the first year (HR 6.00, 95% CI 1.56-23.09, p=0.009) were independent predictors of death/retransplantation, while IVUS parameters were not.
Conclusions—Invasive measures of coronary physiology (FFR and IMR) determined early after heart transplantation are significant predictors of late death or retransplantation.
- Received August 10, 2015.
- Revision received March 9, 2016.
- Accepted March 14, 2016.