Myocardial extracellular volume assessed by cardiovascular magnetic resonance may predict adverse left ventricular remodeling in rheumatic heart disease after valvular surgery

Background: Only a few studies to date have focused on the application of cardiovascular magnetic resonance (CMR) in rheumatic heart disease (RHD); in particular, research on the application of T1-mapping CMR sequences is limited. This study aimed to investigate whether diffuse myocardial fibrosis evaluated using preoperative T1 mapping and extracellular volume (ECV) fraction measurement could predict the progression of adverse left ventricular remodeling (LVR) after surgery. Methods: A total of 32 adult patients with RHD and 30 healthy controls were recruited. Baseline clinical characteristics, CMR findings, and T1 mapping measurements were compared between the two groups. Transthoracic echocardiography measurements were collected before and after surgery. Patients with an increase in left ventricular end-diastolic volume of >15% or a decrease in left ventricular ejection fraction of >10% were classified into the adverse remodeling group; otherwise, patients were categorized into the nonadverse remodeling group. Results: Compared with the healthy controls, patients with RHD had impaired biventricular function, enlarged ventricular volume, and increased native T1 and ECV values. Patients in the adverse remodeling group had higher ECV values than those in the non-adverse remodeling group (33.25%+/- 3.67% vs. 28.45%+/- 4.46%, P=0.002). Binary logistic regression analysis showed that the ECV value was associated with adverse LVR (odds ratio: 1.273, P=0.045). ECV was found to be a sensitive biomarker for predicting adverse LVR (area under the curve: 0.78; sensitivity: 75.0%; specificity: 77.3%). Conclusions: ECV has potential value for predicting the progression of adverse LVR and for identifying non-responders among patients with RHD undergoing surgery.