We present a patient with asymptomatic apical hypertrophic cardiomyopathy (AHCM) who recently developed cardiac arrhythmias, and shortly discuss the diagnostic modalities, differential diagnosis, and treatment strategy for this condition. AHCM is a rare form of hypertrophic cardiomyopathy, which usually involves the apex of the left ventricle. AHCM can occur with varied presentations such as chest pain, palpitations, dyspnea, syncope, atrial fibrillation, myocardial infarction, embolic events, ventricular fibrillation, and congestive heart failure. The most peculiar electrocardiogram findings are giant T-waves inversion in the precordial leads with left ventricular (LV) hypertrophy. A transthoracic echocardiogram is the initial diagnostic modality in the evaluation of AHCM and shows hypertrophy of the LV apex. Other diagnostic modalities, including left ventriculography, multislice spiral computed tomography, and cardiac magnetic resonance imagings, are also valuable tools. Medications used to manage include verapamil, beta-blockers, and antiarrhythmic agents. An implantable cardioverter defibrillator (ICD) is recommended for high-risk patients.

We describe a patient with asymptomatic apical hypertrophic cardiomyopathy (AHCM) who later developed cardiac arrhythmias, and briefly discuss the diagnostic modalities, differential diagnosis and treatment option for this condition. AHCM is a rare form of hypertrophic cardiomyopathy which classically involves the apex of the left ventricle. AHCM can be an incidental finding, or patients may present with chest pain, palpitations, dyspnea, syncope, atrial fibrillation, myocardial infarction, embolic events, ventricular fibrillation and congestive heart failure. AHCM is frequently sporadic, but autosomal dominant inheritance has been reported in few families. The most frequent and classic electrocardiogram findings are giant negative T-waves in the precordial leads which are found in the majority of the patients followed by left ventricular (LV) hypertrophy. A transthoracic echocardiogram is the initial diagnostic tool in the evaluation of AHCM and shows hypertrophy of the LV apex. AHCM may mimic other conditions such as LV apical cardiac tumors, LV apical thrombus, isolated ventricular non-compaction, endomyocardial fibrosis and coronary artery disease. Other modalities, including left ventriculography, multislice spiral computed tomography, and cardiac magnetic resonance imagings are also valuable tools and are frequently used to differentiate AHCH from other conditions. Medications used to treat symptomatic patients with AHCM include verapamil, beta-blockers and antiarrhythmic agents such as amiodarone and procainamide. An implantable cardioverter defibrillator is recommended for high risk patients.

Echocardiography plays a central role in the diagnosis of hypertrophic cardiomyopathy (HCM). However, apical involvement of HCM may be missed because of foreshortening and inadequate clinical suspicion. These patients may be referred for single-photon emission computed tomography imaging.

We present three cases of HCM predominantly involving the cardiac apex, whose diagnosis was first suspected on myocardial perfusion imaging. These patients were referred for chest pain syndromes to exclude significant coronary artery disease. All were undiagnosed on initial routine transthoracic echocardiography, and none were specifically suspected by the referring clinicians. All cases underwent an adenosine stress rest technetium-99m tetrofosmin myocardial perfusion protocol, and were subsequently referred for transpulmonary contrast echocardiography.

Single-photon emission computed tomography imaging revealed increased tracer uptake in all cases, most marked in the apical myocardium. Inferior wall ischaemia was detected in one case, consistent with a coronary stenosis seen at angiography. Apical hypokinesia was noted in two patients on gated studies. Contrast echocardiography confirmed the diagnosis of HCM with apical involvement in all cases.

Echocardiography is the first-line imaging technique for the diagnosis of HCM, but apical involvement may be missed unless a contrast study is performed. The presence of increased apical tracer uptake on perfusion imaging should alert the referring physician to the possibility of apical HCM, irrespective of earlier echocardiographic findings.

The echocardiographic diagnosis of apical hypertrophic cardiomyopathy can be difficult in patients with poor acoustic windows. However, contrast-enhanced echocardiography can provide better images in these patients and lead to the correct diagnosis. We present a patient with apical hypertrophic cardiomyopathy who was diagnosed using contrast-enhanced echocardiography. The use of contrast-enhanced echocardiography for the diagnosis of apical hypertrophic cardiomyopathy in patients with poor acoustic windows is discussed and the experience in the literature reviewed.