Log in to MyACC
CFR on PET and Mortality After Heart Transplant
Study Questions:
Is coronary flow reserve (CFR) determined noninvasively by positron emission tomography (PET) related to survival after heart transplantation?
Methods:
Patients with prior heart transplant were prospectively enrolled in a registry and followed for death from any cause. Rest and dipyridamole stress PET scans were performed using rubidium-82 as a flow tracer. CFR was quantified using compartmental modeling. The primary outcome was death from any cause. The secondary outcome was the composite of myocardial infarction, revascularization, and death from any cause. A subset of patients underwent repeat PET testing.
Results:
A total of 89 patients underwent one PET scan, and follow-up imaging was performed after 1.9 ± 0.3 years in 69 of them. Among 43 patients with coronary angiography, those with mild (n = 11) or no evidence (n = 28) of allograft vasculopathy had higher CFR than those with more severe vasculopathy (n = 4) (2.29 vs. 1.43, p = 0.013), although there was no difference between those with no allograft vasculopathy and those with any degree of vasculopathy (2.3 vs. 2.1, p = 0.25). After a median follow-up of 8.6 years, 40 patients died, mostly from cardiovascular causes, 4 had myocardial infarctions, and 14 underwent revascularization. CFR ≤1.5 had a 2.8-fold increased risk of death compared to >1.5.
Conclusions:
CFR is associated with allograft vasculopathy and adverse outcomes including death after heart transplantation.
Perspective:
This study adds to a growing body of literature supporting the use of PET CFR measures for surveillance for allograft vasculopathy after heart transplantation and adds to prior literature from at least three other centers. The added value of this study is the relatively long duration of follow-up and large number of events, along with added data on repeated measurements. Unfortunately, stress PET is not yet widely available, even among transplant centers. The extent to which these results generalize to MRI or other noninvasive measures of CFR is unknown. Further, repeated measures of CFR require careful standardization in clinical practice, which is challenging in some situations. Finally, future research should evaluate whether PET CFR–guided therapeutic choices improves clinical outcomes.
Clinical Topics: Cardiac Surgery, Cardiovascular Care Team, Heart Failure and Cardiomyopathies, Invasive Cardiovascular Angiography and Intervention, Noninvasive Imaging, Cardiac Surgery and Heart Failure, Statins, Acute Heart Failure, Heart Transplant, Interventions and Imaging, Angiography, Computed Tomography, Magnetic Resonance Imaging, Nuclear Imaging
Keywords: Allografts, Coronary Angiography, Diagnostic Imaging, Dipyridamole, Heart Failure, Heart Transplantation, Magnetic Resonance Imaging, Myocardial Infarction, Myocardial Revascularization, Positron-Emission Tomography, Rubidium, Rubidium Radioisotopes
< Back to Listings
