Work

Myocardial perfusion reserve is low in heart transplant patients and is related to exercise capacity

Year: 2026

Type: article

Abstract: Aims Heart transplant (HTx) patients are known to be at risk of coronary microvascular dysfunction as well as having decreased exercise capacity. The aim of this study was to investigate if microvascular function in HTx patients differs from healthy controls and is related to objective measures of exercise capacity. Methods and Results Twenty‐nine HTx patients (51 ± 15 years, 34% women) and 26 healthy controls (57 ± 10 years, 38% women) underwent CMR. Quantitative myocardial perfusion maps were acquired using single‐bolus (0.05 mmol/kg), dual‐sequence perfusion mapping at adenosine stress and at rest. In addition, all HTx patients performed a maximal cardiopulmonary exercise test with gas‐exchange analysis for objective assessment of exercise capacity. Heart transplant patients had lower stress myocardial perfusion (2.9 ± 0.8 vs 3.4 ± 0.8, p = 0.03) and lower myocardial perfusion reserve (MPR) (2.7 ± 0.7 vs 3.8 ± 1.2, p < 0.001) compared to healthy controls. Furthermore, MPR in HTx patients was correlated with maximal workload (R 2 = 0.25, p = 0.016), O 2 pulse (R 2 = 0.21, p = 0.026), peak O 2 consumption (VO 2 peak) (R 2 = 0.25, p = 0.015) and O 2 consumption (VO 2 ) at the anaerobic threshold (AT) (R 2 = 0.27, p = 0.011). Conclusion Microvascular function as assessed by quantitative CMR perfusion mapping is lower in HTx patients than in healthy controls and is partly related to objective measures of exercise capacity.

Source: Clinical Physiology and Functional Imaging

DOI: 10.1111/cpf.70082