Midventricular Hypertrophic Cardiomyopathy with Apical Aneurysm: Potential for Underdiagnosis and Value of Multimodality Imaging

Archana Sivanandam,Karthik Ananthasubramaniam

doi:10.1155/2016/9717948

Archana Sivanandam, Karthik Ananthasubramaniam

Open Access

https://doi.org/10.1155/2016/9717948

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Abstract

We illustrate a case of midventricle obstructive HCM and apical aneurysm diagnosed with appropriate use of multimodality imaging. A 75-year-old African American woman presented with a 3-day history of chest pain and dyspnea with elevated troponins. Her electrocardiogram showed sinus rhythm, left atrial enlargement, left ventricular hypertrophy, prolonged QT, and occasional ectopy. After medical therapy optimization, she underwent coronary angiography for an initial diagnosis of non-ST segment elevation myocardial infarction. Her coronaries were unremarkable for significant disease but her left ventriculogram showed hyperdynamic contractility of the midportion of the ventricle along with a large dyskinetic aneurysmal apical sac. A subsequent transthoracic echocardiogram provided poor visualization of the apical region of the ventricle but contrast enhancement identified an aneurysmal pouch distal to the midventricular obstruction. To further clarify the diagnosis, cardiac magnetic resonance imaging with contrast was performed confirming the diagnosis of midventricular hypertrophic cardiomyopathy with apical aneurysm and fibrosis consistent with apical scar on delayed enhancement. The patient was medically treated and subsequently underwent elective implantable defibrillator placement in the ensuing months for recurrent nonsustained ventricular tachycardia and was initiated on prophylactic oral anticoagulation with warfarin for thromboembolic risk reduction.

Highlights

Hypertrophic cardiomyopathy (HCM) is an inherited disorder of the cardiac muscle and is well known as the most common cause of sudden cardiac death in individuals less than 35 years of age in North America
We present a case where initial diagnosis of apical ballooning (Takotsubo cardiomyopathy) was suspected at coronary angiography, but subsequent multimodality imaging with echocardiography and magnetic resonance established the unique entity of midventricular HCM with apical aneurysm
She had multiple bouts of nonsustained ventricular tachycardia. She subsequently underwent implantable cardioverter defibrillator placement and was initiated on warfarin for stroke prevention. This case represents an uncommon variant of HCM, namely, midventricular obstructive variant with apical aneurysm formation, which occurs in only 1-2% of HCM patients [1]

Summary

Introduction

Hypertrophic cardiomyopathy (HCM) is an inherited disorder of the cardiac muscle and is well known as the most common cause of sudden cardiac death in individuals less than 35 years of age in North America. It is an autosomal dominant condition with reported prevalence of 1 in 500. Only 25–35% of the patients demonstrate obstruction at rest, provocable gradients can be demonstrated in up to 75% of HCM patients [1]. We present a case where initial diagnosis of apical ballooning (Takotsubo cardiomyopathy) was suspected at coronary angiography, but subsequent multimodality imaging with echocardiography and magnetic resonance established the unique entity of midventricular HCM with apical aneurysm

Case Report

36 Hz 14 cm Aneurysmal apex shown with contrast

Discussion

Findings

Conclusion

Conflict of Interests