Comparisons of Left Ventricular Hypertrophy due to Essential Hypertension and Hypertrophic Non-Obstructive Cardiomyopathy

Essential hypertension (EH) and hypertrophic non-obstructive cardiomyopathy (HNCM) are representative conditions associated with left ventricular hypertrophy (LVH). We compared the severity and distribution of LVH between these two conditions.This study included 44 patients with EH and 79 with HNCM exhibiting precordial negative T-waves (NTs) without LV heart failure. Electrocardiographic assessments included measurements of SV1 + RV5 and the maximum depth of NTs, and routine echocardiographic indices were measured.The SV1 + RV5 and maximum depth of NTs were greater in HNCM than in EH. A correlation was found between these two indices in both groups, with the correlation slope being 4.8 times steeper in the HNCM group. The difference in correlation slopes was considered to reflect the degree of myocardial ischemia. The maximum depth of NTs was predoinantly recorded in the V6 lead in EH, and the V4 and V5 leads in HNCM. Interventricular septal thickness (IVST) was greater in HNCM, whereas LV posterior wall thickness (PWT) was higher in EH. The IVST/PWT ratios were calculated as 0.91 ± 0.10 in EH and 1.20 ± 0.35 in HNCM (P< 0.0001). No significant difference was found in the LV mass index between the two groups. The areas under the receiver operating characteristic curve for the maximum depth of precordial NT and the maximum depth of precordial NT/SV1 + RV5 ratio were 0.967 and 0.952, respectively.LVH was similar between EH and HNCM; however, myocardial ischemia was more severe in HNCM than in EH. The distribution pattern of LVH differed markedly between these two conditions.