Prognostic implications of the compensatory nature of left ventricular mass in arterial hypertension.

OBJECTIVE: To test whether inappropriate echocardiographic left ventricular (LV) mass (i.e. higher than predicted by individual body size, sex and cardiac load [delta%LVM]) is associated with an increased rate of cardiovascular events, and whether values of LV mass lower than appropriate confer protection.
DESIGN: Prospective, longitudinal.
SETTING: Institutional, hospital outpatient clinic. PATIENTS: A total of 294 hypertensive patients, 84 with inappropriate and 21 with low LV mass (lower than appropriate). MAIN OUTCOME MEASURES: Cardiovascular fatal and non-fatal events.
RESULTS: Baseline delta%LVM was higher in patients with follow-up total (n = 50) or fatal (n = 14) events than in event-free survivors (all P < 0.0001) and predicted events independently of age and systolic pressure (all P < 0.0001). Although the performance was not better than with use of more traditional definition of LV hypertrophy, delta%LVM remained a predictor even in the subgroup of 126 patients (32 total events, 13 deaths) with clear-cut LV hypertrophy (P < 0.009). Patients with low LV mass exhibited supranormal LV chamber and midwall function, slightly higher heart rate and higher cardiac index (all P< 0.01). These patients had the same rate of events as those with appropriate LV mass.
CONCLUSIONS: In hypertensive patients, increase in LV mass beyond values required to compensate cardiac workload at a given body size and sex predicts cardiovascular risk independently of age and blood pressure, in the whole population as well as in the subset of patients with LV hypertrophy. Hypertensive patients with levels of LV mass lower than needed to compensate cardiac workload exhibit hyperdynamic circulatory status and the same risk pattern as patients with higher values of LV mass, possibly due to activation of the sympathetic system.