Left ventricular hypertrophy and cardiovascular risk stratification : impact and cost-effectiveness of echocardiography in recently diagnosed essential hypertensives

BACKGROUND: Echocardiography is more accurate than electrocardiography in the assessment of cardiac target organ damage related to hypertension, thus leading to a more precise stratification of total cardiovascular risk. However, ultrasound examination of the heart on a routine basis remains a matter of debate. OBJECTIVE: To evaluate the impact and cost-effectiveness of echocardiographic examination on global risk stratification in low and medium-risk hypertensive patients in relation to age and sex. METHODS: A total of 580 untreated hypertensive individuals (355 men and 225 women, mean age 47.8 ± 11.4 years), classified at low to medium risk, according to routine clinical work-up suggested by the 2003 European Society of Hypertension/European Society of Cardiology guidelines, were included in the study. Total risk was reassessed by adding the results of ultrasound examination of the heart. Left ventricular hypertrophy (LVH) was defined as a left ventricular mass index of 125 g/m or more in men and 110 g/m or more in women. The impact of LVH in stratifying risk was assessed according to age (< 50 and ≥ 50 years) and sex. RESULTS: According to routine classification, 16.3% (n = 93) of the 580 patients were considered to be at low added risk and 83.7% (n = 487) at medium added risk. In the whole population, echocardiographic LVH was found in 86 patients (14.8%) who were then reclassified in the high-risk stratum. The prevalence rates of patients reclassified in the high-risk class as a consequence of LVH detection, according to age and sex, were as follows: 8.9% in men under 50 years, 12.3% in women under 50 years, 26.7% in men aged 50 years and over and 15.3% in women aged 50 years and over. The cost per detected case of LVH was €595 in patients under 50 years of age and €290 in those 50 years of age and older. CONCLUSIONS: Our findings indicate that the prevalence of LVH, and consequently the probability of upgrading the total cardiovascular risk profile, is highest in the group of old hypertensive men; echocardiography has a limited impact on the risk reclassification in younger patients and an unfavourable cost-effectiveness profile. Our data thus do not support the systematic ultrasound assessment of the heart in all uncomplicated hypertensive individuals.