10.7 QT/RR Slope: a Novel Arrhythmogenic Substrate in Hypertensive Left Ventricular Hypertrophy
- PDF / 50,792 Bytes
- 1 Pages / 592.441 x 751.181 pts Page_size
- 36 Downloads / 183 Views
High Blood Press Cardiovasc Prev 2008; 15 (3): 171-215 1120-9879/08/0003-0171/$48.00/0 © 2008 Adis Data Information BV. All rights reserved.
Nervous System 10.7 QT/RR Slope: a Novel Arrhythmogenic Substrate in Hypertensive Left Ventricular Hypertrophy G. Schillaci (1), G. Pucci (1), M. Pirro (1), J. Helou (1), G. Vaudo (1), L. Pasqualini (1), E Mannarino (1) ` di (1)Medicina Interna, Angiologia e Malattie da Arteriosclerosi, Universita Perugia, Perugia, Italy Introduction. Left ventricular hypertrophy (LVH) portends an increased risk of ventricular arrhythmias and sudden death. QT rate dependence, i.e. the dependence of QT interval from the duration of the preceding cardiac cycle, is a major predictor of ventricular arrhythmias in hypertrophic cardiomyopathy, after myocardial infarction, and in patients receiving antiarrhythmic drug therapy, but data on the QT/RR relation in hypertensive LVH are lacking. Methods. A total of 912 patients with untreated hypertension (57% men; age 49+/-11 years) underwent M-mode echocardiogram and standard 12-lead electrocardiogram. The QT interval was measured manually at the nearest 10 milliseconds in all leads from the onset of the QRS complex to the end of the T wave, and the longest QT interval was chosen. The average of 3 consecutive normal beats was considered for the analysis. Results. In the whole cohort, a direct relationship was found between the duration of RR interval and QT duration (r=0.59, p=51 g/m2.7, n=324, b=0.163) than in those without (n=588, b=0.110). Such difference held in a multiple linear regression model (multiplicative interaction term "RR°—LVH": β=0.749, p
Data Loading...
