Strain-Encoded Cardiac Magnetic Resonance for the Evaluation of Chronic Allograft Vasculopathy in Transplant Recipients

Abstract

The aim of our study was to investigate the ability of Strain-Encoded magnetic resonance imaging (MRI) to detect cardiac allograft vasculopathy (CAV) in heart transplantation (HTx)-recipients. In consecutive subjects (n = 69), who underwent cardiac catheterization, MRI was performed for quantification of myocardial strain and perfusion reserve. Based on angiographic findings subjects were classified: group A including patients with normal vessels; group B, patients with stenosis <50%; and group C, patients with severe CAV (stenosis ≥ 50%). Significant correlations were observed between myocardial perfusion reserve with peak systolic strain (r = −0.53, p < 0.001) and with mean diastolic strain rate (r = 0.82, p < 0.001). Peak systolic strain and strain rate were significantly reduced only in group C, while mean diastolic strain rate and myocardial perfusion reserve were already reduced in group B and A. Myocardial perfusion reserve and mean diastolic strain rate had higher accuracy for the detection of CAV (AUC = 0.95, 95% CI = 0.87-0.99 and AUC = 0.93, 95% CI = 0.84-0.98, respectively) and followed peak systolic strain and strain rate (AUC = 0.80, 95% CI = 0.69-0.89 and AUC = 0.78, 95% CI = 0.67-0.87, respectively). Besides the quantification of myocardial perfusion, the estimation of the diastolic strain rate is a useful parameter for CAV assessment. In combination with the clinical evaluation, these parameters may be effective tools for the routine surveillance of HTx-recipients.

Longitudinal Myocardial Deformation is Selectively Decreased After Pediatric Cardiac Transplantation: A Comparison of Children 1 Year After Transplantation With Normal Subjects Using Velocity Vector Imaging

“…Strain and diastolic strain rate also have shown potential for the future detection of coronary vasculopathy [13]. Therefore, future studies using VVI to analyze global strain as well as regional strain and strain rate in pediatric heart transplant patients and to detect both subclinical graft rejection and transplant coronary vasculopathy will be of great interest.…”

Comprehensive Bio-Imaging Using Myocardial Perfusion Reserve Index During Cardiac Magnetic Resonance Imaging and High-Sensitive Troponin T for the Prediction of Outcomes in Heart Transplant Recipients

“…Fewer studies however, investigated the role of stress perfusion CMR for the detection of CAV. In this regard, we and others previously reported that the myocardial perfusion reserve during vasodilator stress CMR is associated with CAV in HT recipients (8,15). In addition, Miller et al (16) recently demonstrated, using CMR, intravascular ultrasound (IVUS) and fractional flow reserve measures in HT recipients, that MPRI is independently associated with both epicardial and microvascular components of CAV, surpassing the value of surveillance coronary angiography for early CAV detection.…”

“…Interestingly, the cutoff value of <1.3 used for the detection of patients with poor outcomes is close to 1.4, which was selected as cutoff value for CAV detection (8). Different patterns of both infarct-related and infarct-atypical LGE on the other hand, were previously demonstrated in HT recipients and were shown to be associated with the degree of CAV (11).…”

“…This is part of our institutional protocol, performed in HT recipients, as described previously (7)(8)(9). Briefly, a standardized imaging protocol was used, aiming at the assessment of baseline parameters of the left ventricle such as left ventricular (LV) diameters, septal and lateral wall thickness and, ejection fraction using cine imaging.…”

“…Myocardial perfusion reserve was assessed during pharmacologic hyperemia with adenosine in all patients. By this approach, a mean myocardial perfusion reserve index (MPRI) was calculated by dividing the blood pool corrected upslope at pharmacologic hyperemia through the blood pool corrected upslope at rest in 16 myocardial segments, which served as a semi-quantitative estimate of the global perfusion reserve in each patient (8,10). Late gadolinium enhancement (LGE) images were scored visually using a 17-segment model.…”