Adrian Covic, MD, PhD, FRCP (london), FERA, is Professor of Nephrology and Internal Medicine at the University “Grigore T. Popa” Iasi, Romania. He is the Editor-in-Chief (Nephrology) International Urology and Nephrology and Associate Editor of Nephrology Dialysis Transplantation.
Invited commentary from Dr. Adrian Covic on how acute coronary syndrome is an important topic that needs more attention from the medical community. Even though ACS in ESRD lost its first round matchup, it represents a very difficult challenge for both the nephrology and cardiology community.
Impaired renal function is an independent risk factor for acute coronary syndrome (ACS); almost 30% among patients with ST-segment–elevation myocardial infarction (STEMI) and 43% among patients presenting with non–ST-segment–elevation myocardial infarction (NSTEMI) have chronic kidney disease (CKD). Furthermore, patients with CKD have significantly increased mortality after ACS, after percutaneous coronary intervention with or without stenting and after coronary artery bypass and increased risk of bleeding.
ACS has totally different features in CKD patients compared with the general population; the diagnosis of ACS in CKD patients is challenging; first of all, the clinical presentation is markedly different compared with population with normal renal function; second, the utility of troponin I or troponin T assay for diagnosis and management of ACS is limited by varying estimates of sensitivity and specificity. Concerning the prognostic value of these assays, TnI or TnT elevation is associate with amplified short-term mortality based, although this findings was based on weak evidence. Evidence was also lacking regarding the long-term prognostic value of either TnI or TnT.
Additionally, despite its expanding risk for adverse outcomes, CKD patients with ACS are less likely to receive evidence-based therapies, including medications. Patients with CKD seem to benefit with angiography and revascularization compared with medical management alone. In a large registry as well as in sub studies of trials in the setting of NSTE-ACS, the outcome of CKD patients improved with invasive management. Early revascularization was associated with a reduction in 1-year mortality compared to initial medical therapy among ACS patients with eGFR <60 mL/min/1.73 m2. The mortality reduction was evident across all CKD stages (including dialysis patients). However, it is well demonstrated that patients with CKD are less probable to have reperfusion therapy. Nonetheless, the increased risk of in-hospital bleeding and risk of contrast-induced acute kidney injury may limit overall benefit for some of them. But the risk of these complications must be balanced against the ischemic risk.
Additionally, studies from both the Acute Coronary Treatment and Intervention Outcomes Network (ACTION) and the Get with the Guidelines (GWTG)-Coronary Artery Disease (CAD) registries have also shown significantly that patients with CKD are less likely to receive medication (like beta-blockers, ACEi, statins) in ACS. In several cohorts with CKD and ACS, chronic treatment with statin or the combination of aspirin and statin is associated with short-term and long-term better outcomes for in-hospital mortality, as compared to those receiving no therapy or aspirin therapy alone. Also, clopidogrel could decrease mortality and improve cardiovascular outcomes without increasing risk of bleeding in ACS patients with CKD; however, this benefit is no longer obvious in elderly CKD patients, and the risk of bleeding is increased.
In this context, it is necessary
- to be more suspicious in CKD patients with atypical signs of ACS (fatigue, shortness of breath, etc);
- provide a better inclusion and better representation of patients with CKD in randomized clinical trials for an accurately assessment of the risks and benefits of revascularization and medications in this population.