Vnitr Lek 2010, 56(7):669-675

ECG markers in patients with hypertrophic cardiomyopathy

K. Hudecová^1,*, I. Šimková², M. Bernadič¹

¹ Ústav patologickej fyziológie Lekárskej fakulty UK Bratislava, Slovenská republika, prednosta doc. MUDr. Marián Bernadič, CSc., mim. prof.

² Kardiologická klinika Slovenskej zdravotníckej univerzity a Národného ústavu srdcových a cievnych chorôb Bratislava, Slovenská republika, prednosta prof. MUDr. Róbert Hatala, CSc.

Background:
Hypertrophic cardiomyopathy (HCM) is an autosomal dominant inherited disease of the heart muscle whose main characteristic is unexplained hypertrophy of the left ventricle and/or right ventricle. It is considered to be the most common genetically determined cardiovascular disease with the prevalence in the population approximately 1 to 500 inhabitants. The disease is associated with severe complications such as heart failure, arrhythmias and sudden cardiac death (SCD). Nowadays the aim of intensive clinical research is to judge the contribution of noninvasive methods in the risk stratification of HCM patients. Abnormal electrocardiogram occurs in 75-95 % and it often presents the first point for HCM suspicion although it is nonspecific.

Aim:
The aim of our study was to evaluate the electrocardiographic (standard 12-lead) and certain echocardiographic markers in patients with recurrent syncope of unknown origin in comparison with patients without these episodes.

Patients and methods:
42 patients (17 men a 25 women) with verified HCM diagnosis underwent extensive clinical, standard 12-lead electrocardiographic and echocardiographic testing to compare these parameters in the subgroup of patients with syncope (n = 17) of unknown origin and patients without syncope (n = 23).

Results:
As for the electrocardiographic signs we found that more than one half of patients had positive Sokolow-Lyon index (55.6%), prolonged QTc interval (63.2%). Depression of ST segment was present in 60.5%. We also found positive correlation between prolonged QTc interval and maximal left ventricle thickness. We observed that patients with syncope had statistically significantly left ventricle end-diasotlic diameter in comparison with patients without syncope.

Conclusion:
Standard electrocardiography represents a "gold standard" in the diagnostics of HCM patients. We found positive correlation between prolonged QTc interval and maximal left ventricle thickness. Patients with syncope had statistically significantly smaller left ventricle end-diastolic diameter in comparison with patients without syncope.

Keywords: hypertrophic cardiomyopathy; ECG; echocardiography; syncope; diagnostics

Received: May 14, 2010; Published: July 1, 2010  Show citation