Hughes RK, Camaioni C, Augusto JB, et al. - Researchers investigated whether impaired myocardial blood flow and myocardial perfusion reserve, recorded via perfusion mapping cardiac magnetic resonance, can occur in the absence of overt left ventricular hypertrophy (LVH) and late gadolinium enhancement, among mutation carriers without LVH criteria for hypertrophic cardiomyopathy (HCM) (genotype‐positive, left ventricular hypertrophy‐negative). In this single center, case‐control study, cardiac magnetic resonance was performed among participants. Longer indexed anterior mitral valve leaflet length, lower left ventricular end‐systolic volume and higher left ventricular ejection fraction were present in individuals with genotype‐positive, left ventricular hypertrophy‐negative. Findings indicate that among HCM mutation carriers, regional and global impaired myocardial perfusion can occur in the absence of significant hypertrophy or scarring.