[White coat arterial hypertension: ultrasonographic study of the carotid arteries].

The prognosis of white coat hypertension is uncertain. The aim of this study was to evaluate the prevalence of atherosclerotic carotid lesions in subjects with white coat hypertension. Compared to both 75 normotensives, and 150 sustained essential arterial hypertensives, 65 subjects with white coat hypertension were studied. Normotensives and hypertensives were divided into dippers, with nocturnal systolic and/or diastolic blood pressure fall of > 10%, and non-dippers. A thickness of > or = 0.95 mm, measured at the level of the common carotid artery, 2-3 cm from flow divider, was considered a sign of myontimal thickening. Plaque was considered as a focal thickening of > or = 2 mm, based on echogenic characteristics and site. Normal carotid arteries, or with myointimal thickening, or with one or more plaques, were similar in subjects with white coat hypertension and normotensives. Compared to subjects with white coat hypertension, sustained hypertensives much more frequently showed a pattern of intima-media thickening (p = 0.04) with one or more plaques (p = 0.01), while normal carotid arteries were less frequent (p = 0.0001). Among white coat hypertensives, dippers showed the same prevalence of normal carotid arteries and carotid lesions as normotensives. In non-dippers sustained hypertensives, compared to dippers, carotid with one or more plaques (p = 0.001) were significantly more frequent, while normal carotid arteries (p = 0.005) were less frequent. Plaques were more often localized at the level of the common carotid artery and bifurcation, and less frequently at the level of the internal and external carotid arteries; more often the lesions were hard, less fibrous, mixed and soft. In conclusion, white coat hypertensives may represent a low risk group. Long-term prospective studies are required to define the prognosis of white coat hypertension.