# Prevalence and Correlates of Dilated and Non-Dilated Left Ventricular Cardiomyopathy in Transfusion-Dependent Thalassemia: Data from a National, Multicenter, Observational Registry

## TL;DR

This study examines heart conditions in patients with a blood disorder called thalassemia and finds that certain heart abnormalities are linked to worse outcomes.

## Contribution

The study identifies non-dilated left ventricular cardiomyopathy as a significant predictor of cardiac complications in transfusion-dependent β-thalassemia patients.

## Key findings

- DCM and NDLVC patients had higher rates of myocardial iron overload and fibrosis compared to NOCM patients.
- Both DCM and NDLVC were associated with significantly increased risk of cardiac complications.
- Age, myocardial iron overload, and cardiomyopathy type were independent predictors of cardiac outcomes.

## Abstract

We investigated the prevalence, clinical characteristics, and prognostic role of dilated cardiomyopathy (DCM) and non-dilated left ventricular cardiomyopathy (NDLVC) in patients with transfusion-dependent β-thalassemia (β-TDT). We retrospectively included 415 β-TDT patients who underwent cardiovascular magnetic resonance to quantify myocardial iron overload (MIO) and biventricular function parameters and to detect replacement myocardial fibrosis. Demographic and laboratory parameters were comparable among patients with no overt cardiomyopathy (NOCM; n = 294), DCM (n = 12), and NDLVC (n = 109), while cardiac size and systolic function were significantly different. Compared to NOCM patients, DCM and NDLVC patients had a higher prevalence of MIO and replacement myocardial fibrosis. During a mean follow-up of 57.03 ± 18.01 months, cardiac complications occurred in 32 (7.7%) patients: 15 heart failures, 15 supraventricular arrhythmias, and 2 pulmonary hypertensions. Compared to the NOCM group, both the NDLVC and the DCM groups were associated with a significantly increased risk of cardiac complications (hazard ratio = 4.26 and 8.81, respectively). In the multivariate analysis, the independent predictive factors were age, MIO, and the presence of DCM and NDLVC versus the NOCM phenotype. In β-TDT, the detection of NDLVC and DCM phenotypes may hold value in predicting cardiac outcomes.