SYNCOPE AND VENTRICULAR ARRHYTHMIAS IN HYPERTROPHIC CARDIOMYOPATHY ARE NOT RELATED TO THE DERANGEMENT OF CORONARY MICROVASCULAR FUNCTION

Citation
R. Lorenzoni et al., SYNCOPE AND VENTRICULAR ARRHYTHMIAS IN HYPERTROPHIC CARDIOMYOPATHY ARE NOT RELATED TO THE DERANGEMENT OF CORONARY MICROVASCULAR FUNCTION, European heart journal, 18(12), 1997, pp. 1946-1950
Citations number
27
Categorie Soggetti
Cardiac & Cardiovascular System
Journal title
ISSN journal
0195668X
Volume
18
Issue
12
Year of publication
1997
Pages
1946 - 1950
Database
ISI
SICI code
0195-668X(1997)18:12<1946:SAVAIH>2.0.ZU;2-V
Abstract
Non-sustained ventricular tachycardia on Holter and syncope have been considered risk factors for sudden death in hypertrophic cardiomyopath y. Aims In these patients the coronary vasodilator reserve is impaired despite normal coronaries, so we evaluated the correlation between th e severity of coronary vasodilator reserve impairment and the occurren ce of syncope and non-sustained ventricular tachycardia. Methods and R esults Eighty-four patients with hypertrophic cardiomyopathy (62 males , age 43 +/- 12 years) had a two-dimensional echocardiographic study a nd a 48-h Holter. Myocardial blood flow was measured by positron emiss ion tomography, at baseline and after dipyridamole, and the coronary v asodilator reserve was computed as dipyridamole myocardial blood flow/ baseline myocardial blood flow. In 27 patients, subendocardial and sub epicardial myocardial blood flow was measured in the septum and the su bendocardial/subepicardial ratio was computed. Twenty of 84 patients h ad at least one syncopal episode, and 26 had at least one run of non-s ustained ventricular tachycardia on Holter. Baseline and dipyridamole myocardial blood flow, coronary vasodilator reserve, and baseline and dipyridamole subendocardial/subepicardial myocardial blood flow ratio were similar in patients with and without syncope and with and without non-sustained ventricular tachycardia on Holter. However, patients wi th nonsustained- ventricular tachycardia had larger left ventricular e nd-diastolic (47+/-6 vs 44+/-5 mm, P<0.05) and end-systolic diameters (30 +/- 6 vs 27 +/- 4 mm, P<0.05). Conclusions (1) Coronary vasodilati on is not more severely impaired in patients with hypertrophic cardiom yopathy and syncope or non-sustained ventricular tachycardia. (2) The left ventricle is more dilated in hypertrophic cardiomyopathy with non -sustained ventricular tachycardia.