To evaluate the prognostic impact of left ventricular (LV) mass exceeding individual needs to compensate hemodynamic load, the percentage of excess of echocardiographic LV mass in relation to individual ideal value predicted by gender, stroke work, and height (in meter(2.7)) from a reference population was assessed in 1019 white hypertensives (627 women [24% obese] and 392 men [17% obese, P<0.02 versus women]) without prevalent cardiovascular disease or type 1 diabetes, from the Italian multicenter, prospective study MAVI. Low LV mass (<73% of predicted) was found in 36 patients (3.5%), 661 had appropriate LV mass, and 322 (37%) had inappropriate LV mass. During follow-up (35+/-11 months), 52 fatal or nonfatal primary cardiovascular events occurred. Age, systolic blood pressure, and LV mass as a percentage of the predicted value were significant predictors of cardiovascular events (all P<0.01), independently of gender, glycemia, antihypertensive treatments, and body mass index, even in subgroups with or without LV hypertrophy. Survival analysis showed that cardiovascular risk increased stepwise from the lowest to the highest quintile of LV mass as a percentage of predicted value (P<0.01). The excess LV mass showed incremental prognostic value compared with assessment of traditional LV mass (P<0.01). Thus, inappropriate LV mass predicts a risk of cardiovascular events, independently of risk factors, and remains a significant predictor of risk either in the presence or in the absence of traditionally defined LV hypertrophy.