Impact of Height Exponents on the Diagnosis and Prognosis of LVH

Abstract

Background

Left ventricular hypertrophy (LVH) is a strong predictor of adverse outcomes. Although normalizing LV mass (LVM) to height exponents reduced variability from body size, specific recommendations for height exponents are lacking due to a scarcity of normal cohorts to define appropriate height exponents.

Objectives

The authors aimed to show the diagnostic and prognostic implications of establishing height exponents specific to sex, ethnicity, and imaging modality.

Methods

Nonoverweight/nonobese Asian healthy volunteers (n = 416) were used to establish appropriate height exponents. The impact of these height exponents was examined in a separate cohort of Asian subjects with hypertension (n = 878). All individuals underwent standardized cardiovascular magnetic resonance imaging. The primary outcome was a composite of acute coronary syndrome, heart failure hospitalization, stroke, and cardiovascular mortality.

Results

The height exponents for healthy female subjects and male subjects were 1.57 and 2.33, respectively. LVH was present in 27% of individuals with hypertension when indexed to body surface area and 47% when indexed to sex-specific height exponents. Most individuals reclassified to LVH with height exponents were overweight or obese. There were 37 adverse events over 60 months (37-73 months) of follow-up. Regardless of indexing method, LVH was independently associated with increased adverse events (height exponent HR: 2.80 [95% CI: 1.25-6.29; P = 0.013]; body surface area HR: 5.43 [95% CI: 2.49-11.8; P < 0.001]).

Conclusions

Reference ranges specific to ethnicity, sex, and imaging modality are necessary to establish appropriate height exponents. Although using height exponents resulted in more LVH reclassification, this did not translate to a notable improvement in event prediction.