From the Guidelines
Yes, there are non-genetic causes of Hypertrophic Cardiomyopathy (HCM), including systemic disorders and secondary causes of left ventricular hypertrophy (LVH) such as athletic training, long-standing systemic hypertension, and hemodynamic obstruction caused by left-sided obstructive lesions. According to the 2020 AHA/ACC guideline for the diagnosis and treatment of patients with hypertrophic cardiomyopathy 1, systemic disorders like metabolic and multiorgan syndromes, mitochondrial myopathies, glycogen/lysosomal storage diseases, and Fabry disease can lead to increased left ventricular wall thickness similar to isolated HCM caused by variants in sarcomeric genes. Some key points to consider include:
- Systemic disorders have different pathophysiologic mechanisms, natural history, and treatment strategies compared to isolated HCM caused by genetic variants.
- Conditions like athletic training (ie, “athletes heart”) and long-standing systemic hypertension (ie, hypertensive cardiomyopathy) can produce secondary LVH that overlaps phenotypically with HCM.
- Hemodynamic obstruction caused by left-sided obstructive lesions or obstruction after antero-apical infarction and stress cardiomyopathy can also cause diagnostic dilemmas.
- Clinical markers and testing strategies can help differentiate between HCM and conditions of physiologic LVH, as stated in the guideline 1. It is essential to distinguish between genetic HCM and these non-genetic causes, as treatment approaches differ significantly, and addressing the underlying cause can lead to improved patient outcomes in terms of morbidity, mortality, and quality of life.
From the Research
Non-Genetic Causes of Hypertrophic Cardiomyopathy (HCM)
- There is no direct evidence in the provided studies to suggest non-genetic causes of Hypertrophic Cardiomyopathy (HCM) [ 2, 3, 4, 5, 6 ].
- However, it is mentioned that mutations in genes responsible for storage diseases can cause a phenotype resembling HCM (genocopy or phenocopy) [ 3 ].
- Additionally, environmental and epigenetic factors can result in heterogeneous disease expression [ 2 ].
- The studies primarily focus on the genetic aspects of HCM, highlighting the importance of mutations in sarcomere genes [ 2, 3, 4, 5 ].
- Current research is focused on developing targeted therapies for HCM, including cardiac myosin inhibitors and gene therapy [ 4, 6 ].