Open AccessPatterns of QT Dispersion in Athletic and Hypertensive Left Ventricular Hypertrophy
Author(s) -
Lonati Laura Maria,
Magnaghi Gaia,
Bizzi Caterina,
Leonetti Gastone
Publication year - 2004
Publication title -
annals of noninvasive electrocardiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.494
H-Index - 48
eISSN - 1542-474X
pISSN - 1082-720X
DOI - 10.1111/j.1542-474x.2004.93565.x
Subject(s) - medicine , left ventricular hypertrophy , qt interval , athletes , cardiology , blood pressure , bruce protocol , electrocardiography , body surface area , muscle hypertrophy , heart rate , physical therapy
Objective: The objective of this article is to assess whether left ventricular hypertrophy (LVH) due to physical training or of hypertensive patients shows similarities in QT length and QT dispersion. Methods: A total of 51 subjects were studied: 17 essential hypertensive patients (27.7 ± 5.6 years), 17 athletes involved in agonistic activity (canoeing) (24.8 ± 6.1 years), and 17 normotensive healthy subjects as control group (24.8 ± 3.6 years). The testing protocol consisted of (1) clinic BP measurement, (2) echocardiography, (3) 12‐lead electrocardiographic examination (QT max, QTc max, QT min, QTc min, ΔQT, ΔQTc). Results: There were no significant differences between the body surface area, height, and age of the three groups. Clinic blood pressure was higher in hypertensives (146.5 ± 45.2/93.5 ± 4.9 mmHg) versus athletes (120.9 ± 10.8/77.1 ± 6.0 mmHg) and controls (123.5 ± 4.8/78.8 ± 2.9 mmHg) by definition. Indexed left ventricular mass (LVM/BSA) was significantly greater in both athletes (148.9 ± 21.1 g/m 2 ) and hypertensives (117.1 ± 15.2 g/m 2 ) versus controls (81.1 ± 14.5 g/m 2 ; P < 0.01), there being no statistical difference among them. LVH (LVMI > 125 g/m 2 ) was observed in all athletes, while the prevalence in hypertensives was 50%. In spite of this large difference in cardiac structure there were no significant differences in QT parameters between athletes and the control group, while hypertensive patients showed a significant increase in QT dispersion versus the two other groups (ΔQT 82 ± 2.1, 48 ± 1.3, 49 ± 2.3 ms; P < 0.01; ΔQTc 88 ± 2.0, 47 ± 1.4, 54 ± 2.7; P < 0.01). Conclusions: LVH induced by physical training activity is not associated with an increase in QT dispersion, whereas pathological increase in LVM secondary to hypertension is accompanied by an increased QT dispersion.