# A Cautionary Tale of Hypertrophic Cardiomyopathy—From “Benign” Left Ventricular Hypertrophy to Stroke, Atrial Fibrillation, and Molecular Genetic Diagnostics: A Case Report and Review of Literature

## TL;DR

A man with a history of stroke and heart issues is found to have a genetic form of heart disease, highlighting the importance of genetic testing in diagnosing complex heart conditions.

## Contribution

The paper highlights the importance of molecular genetic diagnostics in identifying hypertrophic cardiomyopathy and its complications.

## Key findings

- Genetic testing identified three variants in ACTC1, PLN, and SCN5A genes associated with cardiomyopathy and atrial fibrillation.
- The case shows how hypertrophic cardiomyopathy can be overlooked, leading to severe health consequences.
- Advanced diagnostics are crucial for unexplained left ventricular hypertrophy.

## Abstract

This case report concerns a 48-year-old man with a history of ischemic stroke at the age of 41 who reported cardiac hypertrophy, registered in his twenties when explained by increased physical activity. Family history was positive for a mother with permanent atrial fibrillation from her mid-thirties. At the age of 44, he had a first episode of persistent atrial fibrillation, accompanied by left atrial thrombosis while on a direct oral anticoagulant. He presented at our clinic at the age of 45 with another episode of persistent atrial fibrillation and decompensated heart failure. Echocardiography revealed a dilated left atrium, reduced left ventricular ejection fraction, and an asymmetric left ventricular hypertrophy. Cardiac magnetic resonance was positive for a cardiomyopathy with diffuse fibrosis, while slow-flow phenomenon was present on coronary angiography. Genetic testing by whole-exome sequencing revealed three variants in the patient, c.309C > A, p.His103Gln in the ACTC1 gene, c.116T > G, p.Leu39Ter in the PLN gene, and c.5827C > T, p.His1943Tyr in the SCN5A gene, the first two associated with hypertrophic cardiomyopathy and the latter possibly with familial atrial fibrillation. This case illustrates the need for advanced diagnostics in unexplained left ventricular hypertrophy, as hypertrophic cardiomyopathy is often overlooked, leading to potentially debilitating health consequences.