Association of increased QTc dispersion and right ventricular hypertrophy

There have been reports demonstrating an association between increased QT dispersion and ventricular arrhythmia in a variety of pathological cardiac conditions, including left ventricular hypertrophy. However, there are limited data about an association of right ventricular hypertrophy (RVH) and corrected QT (QTc) dispersion.

Eighty-five persons who emigrated from a high-altitude region (2800-4200 m) of Afghanistan to Van, Turkey, (altitude: 1700-1800 m) 25 years ago were referred to our hospital for transthoracic examination between April 2003 and May 2007. RVH was detected in 37 of the persons, 12 of whom were not included in the study due to coexisting systemic hypertension, COPD, or pulmonary hypertension. Twenty-five individuals of the same population with normal echocardiographic findings were enrolled as the control group. Symptoms that may be consequent to arrhythmia (such as palpitation, dizziness, and syncope) were not reported by the study population. Twelve-lead electrography was performed to measure the heart rate, QTc intervals, and QTc dispersion values.

The age and gender of both the patient and control groups were similar. There was no significant difference between patients and controls with respect to QTmax, QTmin, and heart rate. However, mean QTc dispersion values were significantly increased in patients with RVH compared with the control group (59.0+/-14.7 vs. 35.9+/-11.4 ms, p<0.001).

Right ventricular hypertrophy is associated with an increase in QTc dispersion.