Factors underlying the increase in carotid intima-media thickness in borderline hypertensives.

To define the role played by various risk and behavioral factors in the increase of carotid intima-media thickness (IMT) observed in borderline hypertensives. Using B-mode ultrasonography, we compared 97 borderline hypertensives enrolled in the HARVEST study to 27 normotensive controls. Intima-media thickness was measured in the right and left common carotid artery, bulb, and internal carotid artery. Mean IMT (m-IMT), maximum IMT (M-IMT), the mean of M-IMT (M-MAX), and the prevalence of raised lesions (IMT>1 mm) were established. Compared to the controls, higher systolic BP, diastolic BP, mean arterial blood pressure levels and body mass index (BMI) were present in the borderline hypertensives, whereas age, smoking, physical activity, serum cholesterol, and triglycerides were similar. After adjusting for age, sex, heart rate, BMI, smoking, serum cholesterol, triglycerides, and physical activity, higher values of m-IMT and M-IMT were present in most carotid segments of borderline hypertensives compared with controls. After further adjustment for systolic BP and diastolic BP, differences were no longer significant. The adjusted M-MAX was 0.59+/-0.12 in borderline hypertensives compared with 0.50+/-0.10 in controls (P<0.001). After adjustment for systolic BP and diastolic BP it was 0.58+/-0.11 in borderline hypertensives compared with 0.50+/-0.12 in controls (P<0.005). In the various carotid segments, the prevalence of raised lesions was 1. 2% in borderline hypertensives compared with 0.3% in controls (P<0. 001). In the multivariate analysis m-IMT, M-IMT, and M-MAX were related to ambulatory mean arterial pressure, systolic BP and diastolic BP, serum cholesterol and triglycerides, BMI, age, and physical activity. Higher IMT values were found in subjects who were physically active than in those who were sedentary. In borderline hypertensives, an increase in IMT takes place not only in the common carotid artery but also in the bulb and the internal carotid segment. Blood pressure levels are a main determinant of m-IMT while the interaction of BP with other risk factors such as age and plasma lipids is more relevant for advanced intima-media thickening such as M-MAX.

Target organ damage and ambulatory blood pressure in stage I hypertension. The Hypertension and Ambulatory Recording Venetia Study.

According to recent international guidelines the decision on whether to treat young subjects during the early phase of hypertension should be based not only on their office blood pressure but also on their ambulatory blood pressure and whether target organ damage has occurred. Few data on the prevalence of hypertensive complications in young subjects with mild hypertension are available. In the Hypertension and Ambulatory Recording Venetia Study (HARVEST), a multicenter trial conducted in northeast Italy, the percentage of young borderline-to-mild hypertensive subjects with echocardiographic left ventricular hypertrophy was 4.5% and the percentage with concentric remodeling was 4%. Clear differences in cardiac size and geometric adjustment to ambulatory systolic pressure between the two sexes were found. The impact of blood pressure on the walls of the left ventricle and on the left ventricular mass was remarkable in women but weak in men. The assessment of left ventricular systolic function confirmed that many young mild hypertensive subjects have an increased ejective performance. The left ventricular contractility evaluated by midwall measurement was, however, found to be depressed in 9.2% of the HARVEST participants. Their left ventricular diastolic function was similar to that of 50 normotensive controls. The prevalence of microalbuminuria [albumin excretion rate (AER) > 30 mg/24 h) was 6.1%, only slightly higher than that found by other authors among normotensive subjects and much lower than that observed among patients with more severe hypertension. For our stage I hypertensives, however, the AER was correlated to the 24 h blood pressure with high statistical significance, whereas we found no relationship between the AER and left ventricular mass index either for all of the subjects taken together or for the men and women considered separately. The results suggest that renal and cardiac involvement do not occur in parallel during the initial phase of hypertension.

Impaired left ventricular filling in hypertensive left ventricular hypertrophy as a marker of the presence of an arrhythmogenic substrate.

OBJECTIVE: To assess the prevalence of ventricular late potentials and ventricular tachycardia in hypertensive subjects with left ventricular hypertrophy and to study their relation to clinical characteristics. SETTING: Teaching and general hospital in Padua. METHODS: 107 hypertensive subjects with echocardiographic signs of left ventricular hypertrophy were studied with signal averaged electrocardiography and 24 hour Holter monitoring. Signal averaged electrocardiogram analysis was performed with high pass filters of 25 Hz, 40 Hz, and 80 Hz. Ventricular late potentials were considered to be present if at least two determinants of the signal averaged electrocardiogram were abnormal in one of the three filters. 70 normotensive subjects served as age matched controls. RESULTS: 25% (27) of the hypertensive subjects and 6% (four) of the controls showed late potentials on signal averaged electrocardiography (P < 0.0001). The hypertensive subjects with late potentials had a higher prevalence of ventricular tachycardia (33%, 9/27) than those without late potentials (13%, 10/80; P = 0.035). Twenty nine per cent (31/107) of the hypertensive subjects had an inversion of the early to atrial filling velocity (E/A ratio < 1) on Doppler analysis of transmitral flow. Within this group the percentage of subjects with late potentials (55%, 17/31) and ventricular tachycardia (42%, 13/31) was much greater than that within the group of subjects without an inverted E/A ratio (13%, 10/76 (P < 0.0001) and 12%, 9/76 (P = 0.001) respectively). In a multivariate analysis only the E/A ratio was related to the presence or absence of either late potentials (P = 0.0001) or ventricular tachycardia (P = 0.0008). Both late potentials and ventricular tachycardia were unrelated to left ventricular mass, geometry, and systolic performance. CONCLUSIONS: A relation was found between the occurrence of ventricular tachycardia and the presence of late potentials in hypertensive subjects with left ventricular hypertrophy. Impaired left ventricular filling was the main marker for the arrhythmogenic substrate present in this disease.