RELATIONS BETWEEN CARDIAC AND VASCULAR STRUCTURE IN PATIENTS WITH PRIMARY AND SECONDARY HYPERTENSION

Background. Data on cardiac and vascular structure in secondary hypert ension are generally scarce, and no data on the interrelations between cardiac mass and structural characteristics of the vessel wall, both in large and in small resistance arteries, are presently available. Ob jectives. The aim of this study was to investigate the relation betwee n structural changes in subcutaneous small arteries, left ventricular mass and wall thickness of the common carotid artery in patients,vith primary and secondary hypertension. Methods. Seventy-four subjects wer e included in the study: 11 patients with pheochromocytoma, 14 with pr imary aldosteronism (PA), 19 with renovascular hypertension (RVH), 18 with essential hypertension (EH) and 12 normotensive (NT) control subj ects. All subjects were submitted to a biopsy of subcutaneous fat. Mor phologic characteristics of subcutaneous small resistance arteries (re laxed diameter <300 mu m) were directly evaluated using a micromyograp hic technique. All subjects were submitted to calculation of left vent ricular mass index (LVMI) and common carotid artery intima media thick ness (CCIMT), using ultrasound technique. Results. The correlation coe fficients between the media to lumen ratio in subcutaneous small arter ies (MIL) and LVMI or between Mn and CCIMT were closer in RVH than in pheochro mocytoma, EH or NT; in PA the correlation coefficients were s lightly less close than those in RVH. An excess prevalence of carotid plaques in RVH was observed. Conclusions. A close relation between sma ll resistance artery morphology and cardiac or carotid artery structur e may be observed in those hypertensive patients in whom the renin-ang iotensin-aldosterone system is activated. In constrast, in NT, EH and pheochromocytoma no significant correlation between MIL and LVMI or CC IMT was observed. (C) 1998 by the American College of Cardiology.