Diagnostic Value of Cardiac Magnetic Resonance Imaging (CMRI) in the Evaluation of Arrhythmia and Cardiomyopathy.

Background Cardiac magnetic resonance imaging (CMRI) is now the gold standard noninvasive method for evaluating ventricular volume, mass, and ejection fraction - crucial indicators for diagnosing and prognosticating heart failure. Renowned for its accuracy and reliability, CMRI utilizes advanced techniques, such as late gadolinium enhancement and T1 and T2 mapping, to produce three-dimensional images with high spatial and temporal resolution, all without ionizing radiation. One of CMRI's key strengths lies in its capacity to characterize myocardial tissue, providing valuable diagnostic and prognostic insights into underlying cardiac conditions. Recent studies underscore CMRI's feasibility, safety, and emerging cost-effectiveness in selected clinical settings. However, the complex etiologies of arrhythmias and cardiomyopathies, marked by varied structural and functional myocardial changes, continue to present diagnostic challenges. While CMRI's role is expanding, comprehensive observational studies are essential to fully elucidate its diagnostic utility in these cases. Aim This study aims to assess the utility of CMRI in the etiological diagnosis of heart failure and arrhythmias, addressing current knowledge gaps and contributing to clinical practice insights. Overall, CMRI is highlighted as a versatile and effective imaging modality for evaluating diverse aspects of cardiac health. Methods This single-center, hospital-based, non-randomized, prospective observational study was conducted in the cardiology department of Pushpawati Singhania Research Institute (PSRI) Hospital in New Delhi, India, from December 2019 to December 2021. It included patients presenting with arrhythmias, cardiomyopathies, unexplained left ventricular (LV) dysfunction, suspected arrhythmogenic right ventricular dysplasia, myocarditis, hypertrophic cardiomyopathy, as well as infiltrative and granulomatous diseases. Only patients who provided consent for cardiac MRI were included. Cardiac MRI tests were performed and analyzed for all participants to evaluate their diagnostic utility across these conditions. Results The study involved 100 participants, with 75% diagnosed with cardiomyopathy and 25% with arrhythmia. Among the cardiomyopathy cases, 24 patients (32%) had ischemic cardiomyopathy, while 51 patients (68%) had nonischemic cardiomyopathy. LV dysfunction was noted in 65 patients (86.6%), with a viable scar present in three patients (4%) and myocarditis diagnosed in four patients (5.3%). Chamber dilatation was observed in 13 patients (52%). In the arrhythmia group, six patients (24%) exhibited prolonged native T1, while eight patients (32%) had normal cardiac MRI results. These findings highlight the significant utility of cardiac MRI in diagnosing and characterizing various cardiac conditions within the study population. Conclusions The study found that cardiac MRI exhibits a strong positive predictive value in diagnosing various types of cardiomyopathies. This suggests that when CMRI identifies cardiomyopathy, it is likely to provide an accurate diagnosis, thereby enhancing its utility in clinical practice for effective patient management and treatment planning.