Indexation criteria of ventricular mass and predictive role of blood pressure and body composition.

BACKGROUND: There is no definite consensus on which indexation of left ventricular mass (LVM) should be used to better identify left ventricular hypertrophy (LVH). Left ventricular mass has been adjusted to height, to height2.7(h2.7) and to body surface area (BSA). The aims of the present study were to evaluate the prevalence of LVH according to different indexations and different cut-offs and to identify the most useful indexation of LVM to detect hypertension-related LVH. METHODS: Echocardiographic LVH was defined as LVM to h2.7, LVM to BSA, LVM to height, LVM values in the upper 5th percentile of our gender-related LVM distribution, using different partition values suggested in previous population-based studies. RESULTS: Prevalence of LVH in the general population was 32% using the less restrictive criterion (LVH 49.2/46.7 g/m2.7), 15% with the criterion of LVH 116/104 g/m2, and 3.8% with the most restrictive one (LVH 134/110 g/m2). Prevalence of LVH in hypertensive subjects was almost twice than in normotensive subjects with all criteria. Only 20 subjects out of the 707 evaluated were found to have LVH with all six criteria. In multiple regression analysis SBP was independently associated with nonindexed LVM and was indexed to both BSA and h2.7. On the other hand, fat-free mass was a powerful predictor of nonindexed LVM or of LVM to BSA, whereas body mass index was the strongest predictor of LVM to h2.7. CONCLUSIONS: The indexation of LVM to BSA, possibly with the cut-off of LVH 116/104, is probably the best criterion for identifying blood pressure-related LVH.

Relationship between plasma insulin and left ventricular mass in normotensive participants of the Gubbio Study.

BACKGROUND: There is substantial but not conclusive evidence that insulin resistance is related to left ventricular mass (LVM) in hypertensive individuals. To what extent this association is mediated by the relationship between plasma insulin and body size and build is still debated, and is poorly explored in nonhypertensive people. OBJECTIVE: To explore the relationship between insulin or insulin resistance and LVM in a population-based sample of nonhypertensive participants of the Gubbio Study. METHOD: Echocardiographic LVM was determined in 91 nondiabetic, nonhypertensive individuals aged 45-54 years, participating in a population-based screening. LVM normalized for height2.7 was used in the analyses; LV hypertrophy was defined as a value of > or = 50 g/m2.7 in men or > or = 47 g/m2.7 in women. Fasting plasma insulin and glucose were measured and the Homeostasis Model Assessment (HOMA) index was used as a measure of insulin resistance. RESULTS: LVM was positively and significantly correlated with body mass index (BMI) (P < 0.01), waist circumference (P < 0.01) and HOMA index (P < 0.05), whereas correlations with plasma glucose and triglycerides did not reach statistical significance (P = 0.07 for both); all correlations were offset after adjusting for BMI. Fasting plasma insulin and HOMA index were not significantly different in subjects with or without LV hypertrophy (70.8 +/- 27.8 vs. 77.7 +/- 29.6 pmol/l and 2.2 +/- 1.0 vs. 2.6 +/- 1.4, respectively). Bivariate analysis performed stratifying participants above or below the 75th percentile of the sex-specific distribution for BMI (29.1 and 29.4 kg/m2 for males and females, respectively) and plasma insulin (84 pmol/l for either gender), did not result in appreciable differences in LVM due to insulin levels. Similar results were obtained replacing the HOMA index for insulin in the analysis. CONCLUSION: In nonhypertensive individuals left ventricular mass is not associated with plasma insulin independently of body mass index.