Early Detection of Subclinical Myocardial Dysfunction in Familial Dilated Cardiomyopathy Using Myocardial Work Analysis.

Background/

Objectives

Early detection of familial dilated cardiomyopathy (DCM) is crucial for initiating timely interventions. Myocardial work (MW) analysis, which integrates strain imaging and blood pressure, shows promise in identifying subclinical disease. To assess the utility of MW in detecting early myocardial changes in relatives of DCM patients with a positive genotype (G+) compared to genotype-negative (G-) controls.

Methods

This study involved asymptomatic relatives of DCM patients who underwent comprehensive echocardiographic evaluation, including MW analysis. Subjects (N = 77) were classified into G+ (n = 39) and (n = 38) groups based on genetic testing. Myocardial work parameters-myocardial global work index (GWI), global constructive work (GCW), global wasted work (GWW), and global work efficiency (GWE)-were measured. Statistical analyses compared these parameters between groups and assessed their predictive value for genotype status. Follow-up data were collected and analysed accordingly.

Results

Among 77 participants (mean age 36 ± 14 years; 49% women), there were no significant differences in baseline characteristics between G+ and G- groups. S' septal, s' average, e' lateral, E max and E/A were found to be significantly different between the two groups. G+ individuals had significantly reduced GWE (94% vs. 96%, p < 0.001) and increased GWW (113 mmHg% vs. 80 mmHg%, p = 0.001). After adjustment for significant echocardiographic parameters, GWE (OR = 0.746, 95% CI: 0.560-0.994, p = 0.045) and GWW (OR = 1.012, 95% CI: 1.002-1.024, p = 0.047) remained significant predictors of gene carrier status in multivariable analysis. The addition of GWE and GWW significantly increased the area under the curve of a model identifying G+ individuals (p < 0.05). During a median period of follow-up of 53 months, 16 (21%) individuals expressed a cardiomyopathy phenotype. There was a significant correlation between increased baseline GWW, reduced GWE, and the expression of cardiomyopathy phenotype.

Conclusions

Myocardial work analysis, specifically GWE and GWW, identifies early myocardial dysfunction in asymptomatic carriers of genetic variants for DCM. These findings suggest that MW could complement traditional imaging in the early detection and management of familial DCM.