Revascularization of atherosclerotic renal artery stenosis in patients with heart failure.

Renal artery stenosis due to atherosclerotic renovascular disease (ARVD) is common but under-recognized amongst patients with heart failure and chronic kidney disease (CKD). Whether renal artery stenosis is just a manifestation of widespread atherosclerotic disease or a driver of heart failure symptoms, disease progression, and prognosis is controversial and may depend on distinguishing anatomic from functional renal artery stenosis. Anatomical renal artery stenosis can cause nephron damage due to micro-embolization/infarction or activation of inflammatory pathway, leading to a decline in estimated glomerular filtration rate (eGFR) and albuminuria. Functionally significant renal artery stenosis will, in addition, alter renal haemodynamics, favouring water and salt retention, and may cause nephron ischaemia. Clinical manifestations of renal artery stenosis include hypertension, a progressive decline in renal function, worsening heart failure, and 'flash pulmonary oedema'. Anatomical renal artery stenosis can be identified non-invasively using various methods but confirming functional significance may be difficult, creating uncertainty about which patients are likely to benefit from revascularization. If there is a large decline in eGFR after initiating renin-angiotensin-aldosterone system inhibitors (RAASi), this should raise the suspicion of functionally important renal artery stenosis. However, RAASi are an important first line therapy for both ARVD and heart failure. For patients with ARVD and heart failure, RAASi and other guideline-recommended therapies should be initiated with appropriate monitoring of renal function. Further randomized trials investigating the effects of renal revascularization of functionally significant renal artery stenosis on symptoms, renal function, diuretic efficacy, and prognosis in patients with heart failure are required.