[Clinico-instrumental characteristics of the state of the myocardium of patients with long Q-T interval syndrome detected during a population survey].

A comprehensive clinical and instrumental study involving the collection of complaints, resting ECG records, bicycler ergometry, Holter monitoring, echocardiography was performed in 80 Novosibirsk's residents (66 males and 14 females) aged 25-64 years who had the prolonged Q-T interval syndrome detected during a population survey. ECG frequently showed the early ventricular repolarization syndrome (23%) in males and left ventricular hypertrophy (36%) in females. Bicycle ergometry increased Q-T interval in 11% of males and decreased or unchanged it in the remaining cases. Holter monitoring revealed cardiac arrhythmias in 39% of males and 64% of females, supraventricular and monotopic ventricular premature beats being prevalent. The method was found to have advantages in detecting arrhythmias. Echocardiography performed in males made it possible to identify ventricular septum hypertrophy (40%) and mitral valve prolapse (20%). The examinees with the prolonged Q-T interval syndrome mostly had arterial hypertension, coronary heart disease, and alcoholic cardiomyopathy.