Left ventricular 2D speckle tracking echocardiography for detection of systolic dysfunction in genetic, dilated cardiomyopathies.

AIMS: Genetic, dilated cardiomyopathy (DCM) can be caused by a large variety of mutations. Mutation carriers are often asymptomatic until DCM is well established, presenting with heart failure, arrhythmias, or sudden cardiac death. Preventive strategies can only be applied if DCM can be detected early. Echocardiographic, left ventricular (LV) global longitudinal strain (GLS) is a promising tool for early diagnosis, i.e. before a decrease in LV ejection fraction (EF) has occurred. We, therefore, investigated the role of LV GLS as an early disease marker in genetic DCM.

METHODS AND

RESULTS

Genetic DCM patients and genotyped family members were evaluated. The study population was grouped as (i) genotype-positive, phenotype-positive (GPFP) patients with a pathogenic mutation and LVEF <55% (ii) genotype-positive, phenotype-negative (GPFN) individuals with a pathogenic mutation and LVEF ≥55%, and (iii) genotype-negative, phenotype-negative (GNFN) individuals without a pathogenic mutation and LVEF ≥55%. One hundred and fifteen individuals (53 ± 15 years, 51% male) were analysed: 28 (24%) were classified as GNFN, 50 (44%) as GPFN, and 37 (32%) as GPFP. Various mutations were represented: 39 (34%) titin, 14 (12%) lamin A/C, 13 (11%) sarcomeric, and 21 (18%) less frequent mutations (grouped together). The mean LVEF was 58 ± 14% for all subjects. The mean LV GLS in the GNFN group was -21.7 ± 1.5% vs. -19.7 ± 3.5% for the GPFN group (P = 0.036). The mean LV GLS was -12.9 ± 4.3% for the GPFP category (P < 0.001 vs. GPFN and GNFN).

CONCLUSION

Decreased LV GLS discriminates GPFN individuals from normal controls, which may permit early institution of therapy for genetic DCM.