Abstract 4033: Echocardiographic Detection of Left Ventricular Hypertrophy: Which Indexing Method is the Best Predictor of Clinical Outcomes?
Left ventricular hypertrophy (LVH) is a powerful independent risk factor predicting subsequent cardiovascular morbidity and mortality and is clinically best determined echocardiographically as left ventricular mass (LVM) indexed to body size [either body surface area (BSA) or height 2.7 (Ht2.7)]. However, considerable controversy exists regarding which of these two methods is superior for determination of LVH and it’s subsequent outcomes. We evaluated 47,865 patients with preserved ejection fraction to determine the impact of LVM indexed to either BSA (LVH = LVM index >104 g/m2 in women and 116 g/m2 in men) or Ht2.7 (LVH = LVM index >51g/m2.7) on prevalence of LVH and subsequent mortality during an average follow-up of 1.7±1.0 years. Deceased patients (n=3,653) had significantly higher LVM (176.3±69.0 g vs. 166.3±62.3 g, p<0.0001) and prevalence of LVH [by LVM/BSA (25.7% vs. 14.7%, p<0.0001) or by LVM/Ht2.7 (26.2 % vs. 17.7%)] than survivors (n=44,212). Both LVM indices were significantly correlated (r=0.93, p<0.0001) and were concordant in determining the presence or absence of LVH in 93% of patients. In the 7% (n=3214) of patients where categorical LVH was discordant between the two indexing methods, LVH determined by LVM indexed to BSA predicted an increase in mortality compared to patients without LVH (15.2 % vs. 6.7%, p<0.0001) whereas LVH determined by LVM indexed to Ht2.7 did not (7.0% vs. 6.7%, p=NS) (figure⇓). In conclusion, classification of LVH by echocardiography using LVM indexed to BSA is superior to LVM indexed to Ht2.7 in predicting subsequent mortality.