Exercise echocardiography in the evaluation of obstructive types of hypertrophic cardiomyopathy
10.3760/cma.j.issn.0578-1426.2013.06.010
- VernacularTitle:运动负荷超声在评估肥厚型心肌病梗阻类型中的应用
- Author:
Chunli SHAO
;
Fujian DUAN
;
Shubin QIAO
;
Shijie YOU
;
Fenghuan HU
;
Jiansong YUAN
- Publication Type:Journal Article
- Keywords:
Echocardiography;
Cardiomyopathy,hypertrophic
- From:
Chinese Journal of Internal Medicine
2013;(6):484-488
- CountryChina
- Language:Chinese
-
Abstract:
Objective To assess the condition of left ventricular outflow tract obstruction (LVOTO) under resting conditions and physiological exercise in hypertrophic cardiomyopathy (HCM) patients.Methods A total of 60 patients with HCM and left ventri cular outflow tract gradient (LVOTG) < 50 mm Hg (1 mm Hg =0.133 kPa) at rest were enrolled consecutively,and LVOTG at rest and exercise were measured by echocardiography.Of 51 patients with gradients < 30 mm Hg at rest,26 were latent LVOTO with exercise peak value LVOTG ≥ 30 mm Hg,25 were non LVOTO with exercise peak value LVOTG < 30 mm Hg,and 9 were resting obstruction with LVOTG 30-49 mm Hg.The morphological characteristics of different types of obstruction were analyzed.Results Patients with latent LVOTO were more likely to have SAM(73.1% vs 8.0%),narrow of LVOT(46.2% vs 4.0%),higher resting gradients [(16.9 ±7.2) mm Hg vs (7.1 ± 4.3) mm Hg] and mitral regurgitation grade at rest than patients with non-obstructive (all P values < 0.05).The distribution of septal hypertrophy were different in the two groups (P < 0.05).Multivariate logistic regression analysis showed independent predictors of latent LVOTO were SAM (OR 6.431,95 % CI 2.323-291.112,P =0.002) at rest and distribution of septal hypertrophy (OR 0.011,95% CI 0.001-0.179,P =0.008).Conclusions Approximately half of patients with nonobstructive HCM at rest have latent LVOTO.SAM and distribution of septal hypertrophy may be useful to identify patients with latent obstruction.