Hypertrophic cardiomyopathy

Last reviewed: 2 Sep 2023

Last updated: 10 Aug 2022

Hypertrophic cardiomyopathy is the most common cardiomyopathy and the most frequent cause of sudden cardiac death in young people.

Presentation varies from asymptomatic to symptoms of heart failure.

Physical examination may be normal at rest. Auscultation along the left sternal border when the patient is standing after a brief period of exercise may elicit a murmur.

Family history may be present. Echocardiography should be used to screen first-degree family members.

Has a benign prognosis in the majority of patients.

Medical therapy with beta-blockers, calcium-channel blockers, or disopyramide is used in symptomatic patients.

A subset of patients with increased risk for sudden death should undergo defibrillator implantation.

Definition

Hypertrophic cardiomyopathy (HCM) is a genetic disorder characterized by left ventricular hypertrophy (LVH) without an identifiable cause. It is the most common genetic heart disease, as well as the most frequent cause of sudden cardiac death in young people.[1] Given its prevalence in younger patients, HCM is frequently confused with athlete's heart. In older patients, HCM may be misdiagnosed as hypertensive heart disease. Many patients will have no symptoms at the time of diagnosis and will be diagnosed following routine examination or family screening of an affected family member.[1][2]

History and exam

Key diagnostic factors

family history of HCM
history of presyncope or syncope
systolic ejection murmur
left ventricular lift
double apical impulse or double carotid pulsation
family history of sudden death

More key diagnostic factors

Other diagnostic factors

younger male (<50 years)
dyspnea
angina
palpitations
irregularly irregular pulse
older female (>50 years)
collapse
fourth heart sound

Other diagnostic factors

Risk factors

family history of HCM or sudden cardiac death

More risk factors

Diagnostic investigations

1st investigations to order

ECG
CXR
echocardiography

More 1st investigations to order

Investigations to consider

exercise ECG
Holter monitoring
nuclear imaging exercise test
CT coronary arteriography
cardiac catheterization
cardiac MRI
genetic mutation analysis

More investigations to consider

Treatment algorithm

INITIAL

asymptomatic

ACUTE

symptomatic: predominant left ventricular (LV) outflow tract obstruction with preserved systolic function

symptomatic: predominant nonobstructive with preserved systolic function

ONGOING

symptomatic: end-stage heart failure with systolic dysfunction

Contributors

Authors

Theodore Abraham, MD

Professor of Medicine and Radiology

Meyer Friedman Distinguished Professor of Medicine

Co-director, UCSF HCM Center of Excellence

University of California

San Francisco

Disclosures

TA declares that he has no competing interests.

Acknowledgements

Dr Theodore Abraham would like to gratefully acknowledge Dr Monica Mukherjee, Dr Melanie D. Everitt, and Dr Anji T. Yetman, previous contributors to this topic.

Disclosures

MM, MDE, and ATY declare that they have no competing interests.

Peer reviewers

Radhika Kuna, MD

Fellow

Division of Cardiology

University of Maryland Medical Center

Baltimore

Disclosures

RK declares that she has no competing interests.

Saidi Mohiddin, BSc, MBChB

Consultant Cardiologist/Head of Unit

Heart Muscle Disease Unit

Barts and The London NHS Trust

London

Disclosures

SM declares that he has no competing interests.

Differentials
- Athlete's heart
- Discrete subaortic stenosis
- LVH due to hypertension
More Differentials
Guidelines
- Recommendations for multimodality cardiovascular imaging of patients with hypertrophic cardiomyopathy
- 2021 ESC guidelines on cardiac pacing and cardiac resynchronization therapy
More Guidelines
Videos
Fourth heart sound gallop
More videos
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Hypertrophic cardiomyopathy

Summary

Definition

History and exam

Key diagnostic factors

Other diagnostic factors

Risk factors

Diagnostic investigations

1st investigations to order

Investigations to consider

Treatment algorithm

asymptomatic

symptomatic: predominant left ventricular (LV) outflow tract obstruction with preserved systolic function

symptomatic: predominant nonobstructive with preserved systolic function

symptomatic: end-stage heart failure with systolic dysfunction

Contributors

Authors

Theodore Abraham, MD

Disclosures

Acknowledgements

Disclosures

Peer reviewers

Radhika Kuna, MD

Disclosures

Saidi Mohiddin, BSc, MBChB

Disclosures

Differentials

Guidelines

Videos

Log in or subscribe to access all of BMJ Best Practice

Log in or subscribe to access all of BMJ Best Practice

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