Behavioral changes in LV torsion in patients with HCM as compared to normal subjects

摘要

Objectives: The main objectives of our study are 1) To assessmyocardial dysfunction in patients with HCM using tissueDoppler indices 2) To assess myocardial dysfunction by strainimaging using tissue Doppler imaging and 2-D speckle trackingechocardiography.Background: Hypertrophic cardiomyopathy, an autosomal dominantdisorder due to mutation of genes encoding sarcomericproteins, leads to left ventricular diastolic dysfunction. Recentlythe research in this area suggests systolic dysfunction exists inpatients with hypertrophic cardiomyopathy even though traditionalmeasures of systolic dysfunction are normal.Methods: Total 18 patients diagnosed with hypertrophic cardiomyopathyaccording to echocardiography parameters i.e. thicknessof interventricular septum/posterior wall thickness was >1.3or hypertrophy involving apex only with or without left ventricularoutflow tract obstruction were included in the study and werecompared with normal age-matched control. We measured torsionand strain imaging as well as strain imaging by tissue Dopplerechocardiography.Results: The result of the study showed that there is considerableincreased torsion was observed in patients with hypertrophiccardiomyopathy as compared to normal subjects (16.61+7.43vs10.42+4.73, p?0.0005). Tissue Doppler indices - systolic annularvelocity (7.7+0.7 vs. 8.7+1.00, p?0.012) and lateral wall E/E’(12.52+5.27 vs. 6.66+1.67, p<0.001) were significantly different inpatients with hypertrophic cardiomyopathy and normal subjects.The average systolic strain and strain rate as well as diastolicstrain rate were significantly different in both the groups whenstrain imaging performed by tissue Doppler echocardiography.Conclusions: The global subtle systolic dysfunction, as measuredby LV torsion and strain imaging, is present in patients with HCMeven though the patients are having normal ejection fraction orfraction shortening.