Clinical Application of WHF-MOGE(S) Classification for Hypertrophic Cardiomyopathy

Background Recently, a new MOGE(S) (Morphofunctional, Organ involvement, Genetics, Etiology of details of the genetic disease or underlying cause, and functional Status) genotype to phenotype nosology system for classification of cardiomyopathies was proposed, but its clinical use has not been described. Objectives This study presents the comprehensive geno-phenotypic evaluation of hypertrophic cardiomyopathy (HCM) patients by employing the newly proposed World Heart Federation classification of cardiomyopathies - the MOGE(S) classification. Methods From January 2011 to March 2014, 254 patients were evaluated (190 probands and 64 family members). Of those, 181 were HCM phenotype-positive probands, and 54.7% were male patients. Mean maximal left ventricular thickness was 2.2 ± 0.6 cm, with >2.5 cm thickness seen in 21.5% of patients. Obstructive HCM was present in 66.3% of patients, with an average peak gradient of 57.1 ± 47.2. Detailed clinical, imaging, and follow-up data were analyzed. Gene testing was performed in 129 patients (67.9%), and they were categorized into gene-positive (M_HO_HG_ADE_G+) and gene-negative (M_HO_HG_ADE_G-) groups based on the MOGE(S) classification. Results M_HO_HG_ADE_G+ patients were younger at time of diagnosis, more likely to be female, more likely to have ventricular tachycardia and a family history of HCM or sudden death, had lower peak gradients, and were more likely to have sudden death risk factors. Conclusions In addition to employing genotype-to-phenotype nosology to describe HCM, we propose a modification to the current MOGE(S) classification for HCM based on the presence or absence of obstruction and location of hypertrophy within the morphology.