Hypertrophic cardiomyopathy

2020 AHA/ACC guideline for the diagnosis and treatment of patients with hypertrophic cardiomyopathy[2]Ommen SR, Mital S, Burke MA, et al. 2020 AHA/ACC guideline for the diagnosis and treatment of patients with hypertrophic cardiomyopathy: a report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines. Circulation. 2020 Dec 22;142(25):e558-631. https://www.ahajournals.org/doi/10.1161/CIR.0000000000000937 http://www.ncbi.nlm.nih.gov/pubmed/33215931?tool=bestpractice.com

• Left ventricular hypertrophy (LVH) associated with nondilated ventricular chambers in the absence of another cardiac or systemic disease that itself would be capable of producing the magnitude of hypertrophy evident.

• In adults, hypertrophic cardiomyopathy (HCM) is usually recognized by maximal left ventricular (LV) wall thickness 15 mm or greater, with wall thickness of 13 to 14 mm considered borderline, particularly in the presence of other compelling information (e.g., family history of HCM), based on echocardiography.

• Any degree of wall thickness is compatible with the presence of the HCM genetic substrate, and family members may also have disease-causing sarcomere mutations but no evidence of LVH.

2023 ESC guidelines for the management of cardiomyopathies[1]Arbelo E, Protonotarios A, Gimeno JR, et al. 2023 ESC Guidelines for the management of cardiomyopathies. Eur Heart J. 2023 Oct 1;44(37):3503-626. https://academic.oup.com/eurheartj/article/44/37/3503/7246608?login=false http://www.ncbi.nlm.nih.gov/pubmed/37622657?tool=bestpractice.com ​​

• LVH that is not solely explained by abnormal loading conditions.

• In adults, HCM is defined by a wall thickness of 15 mm or greater in any myocardial segment. Wall thickness of 13 to 14 mm requires evaluation of other features, including family history, genetic findings, ECG abnormalities, and echocardiography.

• In first-degree relatives of patients with unequivocal disease (LVH ≥15 mm), diagnosis is based on wall thickness ≥13 mm in any myocardial segment.

The Cardiac Society of Australia and New Zealand position statement for the diagnosis and management of hypertrophic cardiomyopathy[55]The Cardiac Society of Australia and New Zealand. Diagnosis and management of hypertrophic cardiomyopathy - position statement. Nov 2016 [internet publication]. https://www.csanz.edu.au/wp-content/uploads/2017/07/Hypertrophic-Cardiomyopathy_ratified_25-Nov-2016.pdf

• LVH, typically asymmetric in distribution, in the absence of another cardiac cause or systemic condition capable of producing the magnitude of hypertrophy, such as hypertension.

• HCM is usually recognized by a maximal left ventricular wall thickness of 15 mm or greater in adults; 13 to 14 mm is considered borderline, unless there is a definite family history of HCM. Mild hypertrophy related to intense athletic conditioning may occur but should normalize after a period of deconditioning.

• Myocardial biopsy is not needed for the diagnosis but shows characteristic features of myocyte hypertrophy, fiber disarray, and interstitial fibrosis.