Electrocardiographic findings in patients with obstructive and nonobstructive hypertrophic cardiomyopathy.

Abstract

One hundred and thiry-four patients with hypertrophic cardiomyopathy were evaluated by standard 12-lead electrocardiography. Normal electrocardiograms were extremely uncommon, occurring in less than 7% of each subgroup of patients (i.e., those with or without either symptoms or obstruction to left ventricular outflow), with the exception of those who were both asymptomatic and had no left ventricular outflow obstruction. Even in this subgroup, however, normal electrocardiograms occurred in only 27% of patients. Repolarization abnormalities and left ventricular hypertrophy were the most common abnormalities, occurring in 81% and 62%, respectively, of the total population. A broad spectrum of other electrocardiographic abnormalities was found, but none was unique to hypertrophic cardiomyopathy. Patients with vs those without electrocardiographic left ventricular hypertrophy or left atrial abnormality had significantly (P less than 0.005) greater mean ventricular septal thickness (22 +/- 0.6 vs 19 +/- 0.6 mm) and left atrial dimension (48 +/- 1 vs 40 +/- 1 mm) measured by echocardiography, and signficantly (P less than 0.01) higher mean pulmonary capillary wedge pressure (16 +/- 1 vs 10 +/- 1 mm Hg) and left ventricular end-diastolic pressure (20 +/- 1 vs 15 +/- 1 mm Hg). The high prevalence and diverse nature of electrocardiographic abnormalities suggest that any patient with an unusual and unexplained electrocardiogram should be suspected of having hypertrophic cardiomyopathy even if the physical examination is normal, as is often the case in patients without obstruction.

Prevalence of Anderson-Fabry Disease in Male Patients With Late Onset Hypertrophic Cardiomyopathy

“…Both are also described in familial HCM. 11 With regard to arrhythmia, one patient with low ␣-Gal activity had permanent atrial fibrillation and 2 had nonsustained ventricular tachycardia on Holter monitoring. The prevalence and clinical significance of these arrhythmias in Anderson-Fabry disease cannot, however, be determined from the present study.…”

Long-Term Comparison of Apical Versus Asymmetric Hypertrophic Cardiomyopathy

“…[6][7][8] Although apical HCM is considered to be more benign than asymmetric HCM, there is a paucity of data directly comparing apical and asymmetric HCM. 9) In addition, electrocardiographic abnormalities have been reported to be common in patients with HCM 7,10) but most studies have investigated only a small number of patients with asymmetric HCM. No study addressed the characteristics of the J wave, which is associated with growing evidence for sudden cardiac death and clinical implications in patients with HCM.…”

ECG is not a reliable predictor of sudden cardiac death in the general population

“…For this reason, they are difficult to identify among the general population. Nevertheless, even in the asymptomatic persons, the ECG may show characteristic signs of HCM [7], long QT-syndrome [8], short QT-syndrome, arrhythmogenic right ventricular cardiomyopathy (ARVC) [9] Brugada syndrome [10], early repolarization, [11] or WPW [12]. As such, the ECG can identify individuals at risk for SCD.…”