Cardiac magnetic resonance diastolic indices correlate with ventricular filling pressures in pediatric heart transplant recipients

Abstract

Background: Atrial and ventricular filling pressures are routinely used in pediatric heart transplant (PHTx) recipients to assess graft function. We hypothesized that cardiac magnetic resonance (CMR) diastolic indices correlate with filling pressures, providing a noninvasive method of hemodynamic assessment.Methods: Pediatric heart transplant recipients were prospectively enrolled at the time of cardiac catheterization. Pulmonary capillary wedge pressure (PCWP) and right atrial pressure (RAP) were measured. CMR included standard volumetric analysis. Filling curves were calculated by contouring every phase in the short-axis stack.Global longitudinal and circumferential strain (GLS, GCS) were calculated using feature tracking. Atrial volumes and ejection fraction were calculated from 4-chamber and 2-chamber cine images. Correlations were analyzed using Spearman's Rho; modeling was performed with multivariable logistic regression.Results: A total of 35 patients with a mean age of 15.5 years were included, 12 with acute rejection. The median time post-transplant was 6.2 years. Peak filling rate (PFR) and peak LV ejection rate/end-diastolic volume (PER/EDV) correlated with PCWP (rho = 0.48 p = .005, and rho = −0.35 p = .046, respectively) as did GLS and GCS (rho = 0.52 p = .002, and 0.40 p = .01). Indexed maximum and minimum left atrial (LA) volume correlated with PCWP (rho = 0.41, p = .01, rho = 0.41 p = .01), and LA ejection fraction inversely correlated with PCWP (rho = −0.40, p = .02). GLS and GCS correlated with RAP (rho = 0.55, p = .001 and rho = 0.43, p = .01). A model including LV GLS and PFR estimated PCWP ≥12 mmHg with an area under the curve of 0.84. Conclusions:Cardiac magnetic resonance can be a useful noninvasive modality to assess for signs of diastolic dysfunction after PHTx.

Reference data for left ventricular filling and atrial function in children using cardiovascular magnetic resonance

“…LAEF is of particular utility in evaluating diastolic dysfunction as it correlates with elevated LV end-diastolic pressure by invasive measures, and is an indicator of diastolic dysfunction [ 21 , 22 ]. Similarly, in patients with hypertrophic cardiomyopathy, a decline in LA function is often observed prior to LA volume changes or myocardial hypertrophy [ 8 ]. Much of the current understanding of pediatric LA function is extrapolated from adult studies.…”

“…Prior work in adults with various heart diseases demonstrate an association between CMR derived values for PFR, tPFR, PFR/EDV and LAEF and elevated LV end-diastolic pressure [ 22 , 28 – 30 ]. Data in pediatric heart transplant recipients also demonstrates an association between PFR and LA volumes with PCWP, though PCWP was measured under general anesthesia, which likely limited the association [ 8 ]. Given the complexity of diastole, future work should focus on understanding the relationship between CMR diastology metrics and those calculated from cardiac catheterization and echocardiography.…”

“…Cardiovascular magnetic resonance (CMR) provides an alternate, non-invasive method of studying diastolic function via the measurement of leftr atrial (LA) volumes and function as well as LV filling curves. Data from our group suggest CMR diastology correlates with pulmonary capillary wedge pressure (PCWP) in pediatric heart transplant patients [ 8 ]. In addition, our group has demonstrated an association between CMR measures of diastolic function and arrhythmia in tetralogy of Fallot patients [ 9 ].…”

Pediatric heart failure with preserved ejection fraction, a review

“…The FCW/FEW ratio was significantly lower in patients suffering from HFpEF as peak FCW was lower in patients with LV diastolic dysfunction. CMRI is helpful in assessing graft function in pediatric heart transplant recipient ( 75 ).…”