Patterns of left ventricular hypertrophy and late gadolinium enhancement on cardiac MRI in patients with hypertrophic cardiomyopathy and their prognostic significance - An experience from a South Asian country

Objectives: Cardiac magnetic resonance (CMR) imaging is very pertinent in the diagnosis and risk stratification of patients with hypertrophic cardiomyopathy (HCM). We aimed to assess the patterns of left ventricular (LV) hypertrophy, late gadolinium enhancement (LGE), and their prognostic significance in HCM patients in Pakistani population, as no such data are available from Pakistan. Material and Methods: This was a retrospective, single center study. All patients who had confirmed diagnosis of HCM on CMR at Aga Khan University Hospital during the period of 2011-2019 were identified and included in the study. Results: A total of 74 patients were included with the mean age of 45.6 ± 15 years and the majority 71.6 % (n = 53) being male. Maximal LV wall thickness was 21.1 ± 5 mm, asymmetrical septal hypertrophy being the most common pattern (62.2%, n = 46). LGE was present in 75.7% (n = 56) with most common site being septum plus LV free wall (24.3%, n =18). Mean ejection fraction% was found to be lower in patients with LGE (P < 0.001). Major adverse cardiac events (MACE) were observed in 40.5% (n = 30). Presence of LGE and right ventricular involvement was found to have a statistically significant association with MACE (P value 0.018 and 0.046, respectively). In multivariable analysis, only LGE was significantly associated with MACE (odd ratio: 4.65; 95% CI: 1.21-17.88). Conclusion: Asymmetrical septal hypertrophy was the most common pattern of hypertrophy. LGE was present in three fourth of the study population and it was significantly associated with MACE.