• Hypertrophic cardiomiopathy

In adults, Hypertrophic cardiomiopathy is diagnosed in the setting of an end diastolic maximal wall thickness (WTMax) ≥15 or ≥13 mm in presence of family history. We hypothesize that wall thickness standard deviation (WTSD) could be a novel CMR-derived morpho-functional parameter to early diagnose HCM, with a greater diagnostic accuracy then WTMax especially in women.
The best morpho-functional cine-MRI derived parameters resulted from a validation cohort of patients were retrospectively tested in a population of 265 patients with with one of the following conditions present at the time of CMR; a) pathogen mutation for sarcomere gene with negative phenotype; b) definite diagnosis of HCM; c) patients with LV hypertrophy with end-diastolic maximal wall thickness <15 mm that subsequently received a definite diagnosis of HCM. Predictive accuracy of each parameter for HCM diagnois was assessed by comparing areas under the receiver operating characteristic curves (AUC).
The WTSD with a cut off of > 2.27 had a significantly higher AUC compared with each other parameters in validarion group. WTSD > 2.27 and WTMax > 13 mm were confirmed as parameters with the highest value of AUC to distinguish between HCM and healthy controls. In female population WTSD > 2.27 demonstrated a significantly greater diagnostic accuracy then WTMax allowing significant net reclassification of diagnosis.
Asymmetry of LV wall thickness is a hallmark of HCM. This study demonstrated that a marker of the asymmetry, the WTSD is the most accurate morphological parameter to early identify HCM patients even when the typical phenotype is not yes manifested.