Professor Sheldon Tobe, from the Sunnybrook Hospital in Toronto, gave a State-of-the-Art lecture on “How to manage the patient with Renovascular disease post CORAL,” which was followed by a predictably engaging discussion. CORAL, published in 2014 in the NEJM, was perhaps the last nail in the coffin for revascularization of renal arteries, and this topic was reviewed earlier this year by Bohlke and Barcellos, and on the blog also. To start off the session today, Dr. Tobe (who incidentally was one of the CORAL investigators) reviewed a case of a patient with severe bilateral renal artery stenosis (RAS) and uncontrolled hypertension, in whom one of the arteries got even thrombosed by the time the patient arrived under his care. Magnetic Resonance (MR) angiography revealed severe RAS, and Dr Tobe discussed his dilemma about the management. This was before CORAL began, and Dr Tobe admitted to succumbing to the oculo-stenotic reflex, and with great results – better blood pressure, stable kidney function.
Though CORAL is remembered more for the null efficacy outcome, Dr Tobe then highlighted how it did re-establish the safety of stenting itself, in capable hands (which had been thrown into question from the adverse outcomes reported in ASTRAL). Secondly, it did highlight that the best current medical therapy is remarkably effective, which underlies the lack of difference between this and revascularization. Previous to this, the natural history of the disease was that about 5% of patients with RAS > 60% progressed to complete occlusion at 1 year and this proportion increased to 11% by 2 years. He also showed some other (as yet unpublished data) from CORAL, demonstrating that it was level of blood pressure and proteinuria, and not bilaterality of RAS that predicted renal outcomes. However, bilateral RAS did predict cardiovascular outcomes.
In the discussion that followed, there was an astute comment made, that perhaps given that the rate of cardiovascular events in CORAL were still quite high despite optimal medical management, whether these patients represent a more aggressive vascular phenotype. Perhaps a case could then be made, at least for research, into more aggressive risk factor management in these patients with dual anti-platelet agents or high dose statins. There was a longer discussion on the continuing role for stenting – especially in the kind of patients perhaps not included in CORAL, with the hope that data on patients screened and excluded in these trials will be published. Dr Tobe did mention that one of his patients, who was enrolled in CORAL and randomized to medical management, developed worsening hypertension and kidney function, and after a complete discussion, the patient decided to go ahead with stenting, which resulted in stabilization (though this could just be regression to the mean?). Lastly, it was reiterated that anatomic bilateral stenosis should not preclude use of renin-angiotensin system blockade, and in CORAL the ARB used was quite well tolerated by such patients.
– Post written by Dr. Swapnil Hiremath, AJKD Blog Contributor.