Q waves in hypertrophic cardiomyopathy in relation to the distribution and severity of right and left ventricular hypertrophy.

The cause of abnormal Q waves in hypertrophic cardiomyopathy remains unclear. Myocardial wall thickness was assessed by two-dimensional echocardiography at 8 left ventricular and 10 right ventricular sites in 67 patients (mean age 40 years) with hypertrophic cardiomyopathy and the findings were analyzed in relation to the presence of abnormal Q waves on the 12 lead rest electrocardiogram (ECG). Nineteen (28%) of the 67 patients had abnormal Q waves.

Echocardiographic measurement of right ventricular wall thickness in hypertrophic cardiomyopathy: relation to clinical and prognostic features.

Hypertrophic cardiomyopathy is characterized by unexplained left ventricular hypertrophy. It is uncertain, however, to what extent the right ventricle is also thickened. Right ventricular hypertrophy is found at autopsy in patients who die suddenly but, until recently, systematic evaluation of right ventricular morphology has not been feasible.

Echocardiographic measurement of the normal adult right ventricle.

In studies of the right ventricle the complexities of chamber shape may be overcome by use of multiple tomographic imaging planes. An established protocol for the echocardiographic description of the heart was used to examine the right ventricle in an ordered series of transducer locations and orientations. Diastolic measurements were made of the right ventricular inflow tract, outflow tract, and right ventricular body, and the range and reproducibility of normal values for cavity size and right ventricular free wall thickness were established.

The distribution of left ventricular hypertrophy in hypertrophic cardiomyopathy: comparison to athletes and hypertensives.

Cross-sectional echocardiography was performed in 134 patients with hypertrophic cardiomyopathy and 75 with secondary left ventricular hypertrophy (57 hypertensives and 18 athletes) to determine the diagnostic sensitivity and specificity and predictive value of the pattern of left ventricular hypertrophy. Myocardial wall thickness was assessed in the anterior and posterior septum, free wall and posterior wall in both the upper and lower left ventricle. All patients had at least one region exceeding 2 SD from normal (greater than 1.

[Arrhythmias in hypertrophic cardiomyopathy. Significance and therapeutic consequences].

The natural history of the patient with hypertrophic cardiomyopathy is characterized by slow progression of symptoms and left ventricular hypertrophy; severe functional limitation is unusual and encountered only in about 20%. Most of the deaths are sudden and occur irrespective of the functional status of the patient and there are no routine electrocardiographic or hemodynamic measurements indicative of poor prognosis. Sudden death may be associated with syncope and young age at diagnosis as well as with a family history of sudden death.

Amiodarone for long-term management of patients with hypertrophic cardiomyopathy.

Fifty-three patients with hypertrophic cardiomyopathy who had serious arrhythmias (45 patients), refractory chest pain (5 patients) or a high risk of sudden death (3 patients) received amiodarone for 6 to 96 months (median 18) after completion of a loading and an initial maintenance period. The dose of amiodarone was altered by 50 to 200 mg/day at 3- to 6-month intervals, guided by electrocardiographic monitoring, plasma drug level measurements and side-effect questionnaires. Ventricular tachycardia was suppressed in 24 patients (92%) with doses of 100 to 400 mg/day (median 300); none died suddenly during a mean follow-up of 27 months.