Related Experiment Videos
[Renovascular arterial hypertension. From physiopathology to therapy]
E Cunha Telles1, F Silveira Machado, I de Oliveira
1Serviço de Cardiologia, Hospital de Santa Maria, Lisboa.
Abstract:
Understanding the pathophysiology, diagnosis, and management of renovascular hypertension (RVH) is of paramount importance due to the severity of hypertension (HT) and renal insufficiency (RI). Moreover, adequate treatment by surgery and/or endovascular intervention can improve HT and revert RI. The comprehension of the pathophysiology of RVH had its origin on the experiments of Goldblatt which led to the recognition of the renin dependent, volume dependent, and mixed types. A continuum seems to exist, from an acute phase, supported by the endocrine renin angiotensin aldosterone system, evolving towards a chronic phase sustained by the local renin angiotensin system. The involved vasoconstrictor and mitogenic mechanisms may contribute to the arterial remodeling. The most common forms of pathology, i.e. atherosclerosis, fibromuscular dysplasia (FD), and Takayasu's arteritis, and their natural history, are described. The prevalence of RVH, ranging from 0.2% to more than 25%, depending on the clinical situation, is evidenced. Clinical symptoms and signs and the most important diagnostic tests are pointed out: functional tests (captopril test, postcaptopril renography, scintigraphy, and renin determinations) and anatomical tests (intravenous digital angiography and intrarterial angiography). New imaging techniques are also referred. A diagnostic work-up based on the index of clinical suspicion is described. The therapeutic goal is the resolution of the two main problems of RVH: hypertension and ischemic nephropathy. Revascularization is becoming mandatory either by percutaneous transluminal angioplasty mostly for FD and atheromatous non-ostial stenoses, or by surgery, which is preferred for patients with ostial or peripheral stenoses, aneuryms, occlusions and concomitant aortic disease. A better knowledge of RVH allows, not only diagnosis and treatment of one of the most frequent types of secondary hypertension, but also the control of the resulting ischemic nephropathy.