[Usefulness of pulsed Doppler tissue imaging in the early detection of diastolic myocardial abnormalities in first-degree relatives of patients with familial hypertrophic cardiomyopathy].

INTRODUCTION AND OBJECTIVES: Doppler tissue imaging (DTI) enables regional myocardial function to be assessed irrespective of preload. Our aim was to determine the usefulness of DTI in healthy relatives of patients with familial hypertrophic cardiomyopathy.

PATIENTS AND METHOD: We studied 47 first-degree relatives of patients with familial hypertrophic cardiomyopathy (group GI) and 47 normal subjects (group GII). Echocardiographic studies, including DTI, were performed in both groups. DTI was used to measure myocardial velocities during systole (S'), early diastole (E') and atrial contraction (A') at the mitral annulus, septum, and tricuspid annulus. Isovolumic relaxation and contraction times were corrected for heart rate. With DTI assessment of regional diastolic myocardial function and use of the E'/A' ratio, normal (i.e., E'/A'>1) and abnormal (i.e., E'/A'<1) diastolic function could be distinguished.

RESULTS: There were no abnormalities in regional diastolic function in group GII (right E'/A' 1.78 (0.58), septum E'/A' 2.03 (0.53), and left E'/A' 2.55 (0.80). However, in group GI, two subgroup could be distinguished using E'/A' ratio values: group GIa comprised 37 first-degree relatives with normal diastolic function (right E'/A' 1.8 (0.44), septum E'/A' 2.07 (0.41), and left E/A 2.35 (0.6) who did not differ significantly from control subjects, and group GIb comprised 10 first-degree relatives with abnormal right diastolic function (right E'/A' 0.70 (0.28), P<.001) but with less significant differences at the septum (1.57 (0.49), P<.01) and mitral annulus (1.85 (0.53), P<.01).

CONCLUSIONS: In 10 of 47 (21.3%) first-degree relatives of patients with familial hypertrophic cardiomyopathy, DTI enabled the detection of ventricular diastolic abnormalities, which were more evident in the right ventricle. They could be a preclinical manifestation of disease.