Cardiovascular complications according to severity of renal artery stenosis based on Doppler ultrasound

Introduction The interactions between atherosclerotic renal artery stenosis, independently of severity, and cardiovascular risk, and mortality, are complex and have not been fully researched. The aim of this study was the assessment of the risk of cardiovascular events and mortality in patients with haemodynamically non-significant (NS-RAS) and significant renal artery stenosis (S-RAS) diagnosed with ultrasonography. Material and methods The study group consisted of all consecutive patients (n = 2059) who underwent Doppler ultrasound of the renal arteries during a 4-year period. The patients were divided, according to the renal aortic ratio (RAR), into the following groups: S-RAS (RAR ≥ 3.5), NS-RAS (1 < RAR < 3.5), and normal RAR (control group; RAR ≤ 1). The risk of cardiovascular events and death was estimated using Cox’s proportional hazard model, including severity of RAS, age, and gender, based on the data from the National Health Fund on causes of hospitalization, deaths, and statistics on percutaneous coronary angioplasty procedures. Results Significant renal artery stenosis was found in 112 patients (5.4%), NS-RAS in 313 patients (15.2%), and 1634 patients (79.4%) were qualified to the control group. The NS-RAS group had an increased risk of stroke (7.0% vs. 3.0%, HR = 1.77, p = 0.032); S-RAS patients were at increased risk of heart failure (16.1% vs. 5.2%, HR = 2.19, p = 0.002) and death (19.6% vs. 4.3%, HR = 3.08, p < 0.001). Conclusions The presence of haemodynamically non-significant renal artery stenosis is an indicator of systemic atherosclerotic changes in vital organs and an important cardiovascular risk factor for stroke.