Related Experiment Videos
Apical segmental dysfunction in hypertrophic cardiomyopathy: subgroup with unique clinical features
1Research Institute of Angiocardiology and Cardiovascular Clinic, Faculty of Medicine, Kyushu University, Fukuoka, Japan.
Insights
Segmental wall motion abnormalities in hypertrophic cardiomyopathy are rare. Abnormal Q waves on ECG may signal apical dysfunction, warranting further investigation with left ventriculography and ambulatory ECG monitoring.
Area of Science:
- Cardiology
- Cardiovascular Medicine
- Clinical Research
Background:
- Segmental wall motion abnormalities are infrequently observed in hypertrophic cardiomyopathy (HCM).
- Understanding the clinical significance of these abnormalities is crucial for patient management.
Purpose of the Study:
- To investigate the clinical significance of apical segmental wall motion abnormalities in patients with hypertrophic cardiomyopathy.
- To identify potential diagnostic markers and associated complications of this specific HCM phenotype.
Main Methods:
- Analysis of 48 patients with hypertrophic cardiomyopathy, divided into Group A (apical segmental dysfunction) and Group B (normal wall motion).
- Assessment included selective coronary arteriography, left ventriculography, echocardiography, electrocardiogram (ECG), and 24-hour ambulatory ECG monitoring.
- Comparison of clinical and diagnostic findings between Group A and Group B.
Main Results:
- Apical segmental dysfunction was confirmed by left ventriculography in all 8 patients in Group A, but only detected in 2 by echocardiography.
- Abnormal Q waves on ECG were significantly more frequent in Group A (p < 0.005), often in lateral leads, with serial ECGs showing development in 6/8 patients.
- Malignant arrhythmias were more common in Group A (p < 0.001), and two patients developed left ventricular dilation and congestive heart failure.
- No significant coronary artery stenosis was found in any patient.
Conclusions:
- The presence of lateral Q waves on ECG may indicate apical segmental dysfunction in hypertrophic cardiomyopathy.
- Left ventriculography and 24-hour ambulatory ECG monitoring are recommended for patients with lateral Q waves and HCM.
- Patients with this unique HCM presentation require vigilant follow-up due to potential for malignant arrhythmias and heart failure progression.
Abstract:
A segmental wall motion abnormality is an unusual finding in patients with hypertrophic cardiomyopathy. To clarify its clinical significance, 48 patients with hypertrophic cardiomyopathy were analyzed. Eight patients (Group A) had apical segmental dysfunction; 40 (Group B) had normal wall motion. No patient in either group had coronary artery stenosis on selective coronary arteriography. In all patients in Group A, apical segmental dysfunction was revealed by left ventriculography; however, it could be detected by echocardiography in only two patients in Group A. Left ventricular hypertrophy by electrocardiogram (ECG) was more common in Group B (p less than 0.05). Abnormal Q waves were more frequently discovered in Group A (p less than 0.005) and were recognized predominantly in the lateral leads. On serial ECGs, a gradual development of abnormal Q waves was noted in six of eight patients in Group A. Malignant arrhythmias were more common in Group A (p less than 0.001). In two patients in Group A, left ventricular dilation and congestive heart failure developed during the follow-up period. Thus, the presence of a Q wave in the lateral leads on an ECG in patients with hypertrophic cardiomyopathy may indicate the presence of apical segmental dysfunction. Left ventriculography should be performed to examine the presence of this abnormality and 24 h ambulatory ECG monitoring should be done to detect malignant arrhythmias in patients who have abnormal Q waves in the lateral leads. Patients with this unique type of hypertrophic cardiomyopathy need careful follow-up evaluation.