Titin As the Culprit Behind Dilated Cardiomyopathy: A Case Series of Three Cases and a Comprehensive Literature Review.

Nonischemic dilated cardiomyopathy (DCM) is a complex cardiovascular condition often characterized by genetic pathogenesis. Comprehensive genetic testing has become a crucial aspect of DCM diagnosis and management, offering insights into prognosis and the identification of at-risk individuals. We delve into distinct genetic pathways associated with DCM and their pathogenetic mechanisms, emphasizing the evolving significance of genetic markers, particularly in cases where arrhythmia risk is heightened. The historical reliance on cardiac morphology to subtype cardiomyopathies is being complemented by the identification of genetic variants, further refining DCM subtypes and aiding in clinical management. The first case is a 51-year-old male who presented with symptoms of heart failure and non-sustained ventricular tachycardia. The second case is a 65-year-old female who presented with chest pain, shortness of breath, and tachycardia-mediated cardiomyopathy. The third case was a 48-year-old male who had a history of heart failure and non-ischemic cardiomyopathy. Despite immediate and extensive resuscitative measures, the patients' protracted response to the treatment raised questions about the potential underlying genetic factors contributing to their clinical presentation. A genome study was done in all these reported cases, which showed a genetic mutation in the titin gene. These cases underscore the importance of genetic evaluation in unraveling the complexity of cardiomyopathies, ultimately enhancing our ability to manage and treat such challenging cases. This case series, with a comprehensive literature review, explores the mechanisms governing titin-based forces in healthy and diseased conditions. It highlights the influence of isoform diversity and post-translational modifications on myocardial stiffness and contractility.