Renovascular hypertension: Current concepts

Hypertension produced by renal artery occlusive disease is an important secondary form of hypertension. Clinicians commonly encounter forms of renal arterial disease of varying severity, many of which are of little hemodynamic significance when first detected. Experimental studies emphasize that transient activation of the renin-angiotensin-aldosterone system is necessary for initiation of renovascular hypertension. At some point, angiotensin II activates additional mechanisms responsible for sustained increased blood pressure including sodium retention, endothelial dysfunction, and vasoconstriction related to production of reactive oxygen species. Widespread application of agents that block the renin-angiotensin system, including angiotensin-converting enzyme inhibitors and angiotensin-receptor blockers, render many patients with unilateral renal arterial disease manageable primarily by medical means for many years. In the setting of high a priori likelihood of renovascular disease, recognizing the potential for disease progression during medical therapy and individually evaluating the risks and benefits of renal revascularization are important tasks. Recent prospective studies show limited, but real, benefit regarding blood pressure control for patients with atherosclerotic disease. Whether earlier renal revascularization offers benefits regarding improved morbidity and mortality from cardiovascular end point reduction is an important question to be addressed in multicenter, prospective, randomized trials. Our paradigm stresses the fact that patients with renovascular hypertension require intensive blood pressure control and cardiovascular risk factor intervention, both before and after revascularization. Hence, management of such patients requires close attention and periodic review regarding restenosis and progression of vascular disease.