[Relation between disorders of cardiac rhythm to the symptomatology and extent of hypertrophic cardiomyopathy].

The aim of the work was a more detailed characteristic of patients with hypertrophic cardiomyopathy who are threatened by an increased risk of serious disorders of the cardiac rhythm and thus probably also by sudden death. The authors analyzed a group of 64 patients subjected to 24-hour monitoring of the ECG by the Holter system. The patients were subjected to echocardiographic examination and the distribution of the myocardial hypertrophy was described in detail, incl. its extent in per cent of the affected myocardium, the mean thickness of the myocardium (arithmetic mean of the thickness of the left ventricular musculature and septum divided into 10 areas) and the maximum thickness of the heart muscle. The authors found a significantly higher incidence of serious ventricular arrhythmias in patients with an extensive area of the hypertrophy and a greater thickness of the hypertrophic myocardium. In subjects with a positive history of syncopes there was a high incidence of serious supraventricular and ventricular disorders as well as ventricular disorders of the cardiac rhythm. No relationship was found between the incidence of arrhythmias and the presence or size of obstruction. Patients with extensive hypertrophy (i.e. an extensive area of hypertrophy and thickness of the myocardium) and patients with a history of syncopes form thus as regards life-threatening arrhythmias a risk group which after diagnosis should be without delay examined by the Holter system and then treated by medicamentous therapy.