Introduction: According to different authors, cardiac surgery-associated acute kidney injury (CSA-AKI) incidence can be as high as 20–50%. This complication increases postoperative morbidity and mortality and impairs long-term kidney function in some patients. This review aims to summarize current knowledge regarding alterations to renal physiology during cardiopulmonary bypass (CPB) and to discuss possible nephroprotective strategies for cardiac surgeries. Relevant sections: Systemic and renal circulation, Vasoactive drugs, Fluid balance and Osmotic regulation and Inflammatory response. Conclusions: Considering the available scientific evidence, it is concluded that adequate kidney perfusion and fluid balance are the most critical factors determining postoperative kidney function. By adequate perfusion, one should understand perfusion with proper oxygen delivery and sufficient perfusion pressure. Maintaining the fluid balance is imperative for a normal kidney filtration process, which is essential for preserving the intra- and postoperative kidney function. Future directions: The review of the available literature regarding kidney function during cardiac surgery revealed a need for a more holistic approach to this subject.

Left main disease (LMD), combined with carotid artery stenosis (CAS), constitutes a high-risk patient population. Priority is often given to coronary revascularization, due to the severity of the angina. However, the choice of revascularization strategy [off-pump coronary artery bypass (OPCAB) vs coronary artery bypass grafting (CABG)] remains elusive. A total of 1340 patients with LMD were non-randomly assigned to either on-pump (CABG group, n = 680) or off-pump (OPCAB group, n = 634) revascularization between 1 January 2006 and 21 September 2010. Multivariable regression was used to determine the risk-adjusted impact of a revascularization strategy on a composite in-hospital outcome (MACCE), and proportional hazards regression was used to define the variables affecting long-term survival. Significant CAS was found in 130 patients: 84 (13.1%) patients underwent OPCAB, while 46 patients (6.8%) underwent CABG (P < 0.05). Patients with a history of stroke/transient ischaemic attack were also more likely to receive OPCAB (7.1 vs 4.7%; P = 0.08). OPCAB patients were older, in a higher New York Heart Association (NYHA) class, with a lower LVEF and higher EuroSCORE. A calcified aorta was found in 79 patients [OPCAB–CABG: 49 (7.73%) vs 30 (4.41%); P = 0.016] and resulted in a less complex revascularization (OPCAB–CABG: 2.3 ± 0.71 vs 3.19 ± 0.82; P < 0.05), and 30-day mortality was insignificantly higher in the CABG (2.7 vs 2.8%) as well as MACCE (11.2 vs 12.2%; P = NS). This trend reversed when late mortality was evaluated; however, it did not reach significance at 60 months. Preoperative renal impairment requiring dialysis was found to be a technique-independent predictor of MACCE. The number of arterial conduits also influenced MACCE. Off-pump coronary revascularization may offer risk reduction of neurological complications in patients with a significant carotid artery disease and a history of previous stroke, but a larger study population is needed to support this thesis. The growing discrepancy in long-term survival should draw attention to a more complete revascularization in OPCAB patients.

Mechanical circulatory support (MCS) is an umbrella term describing the various technologies used in both short- and long-term management of patients with either end-stage chronic heart failure (HF) or acute HF. Most often, MCS has emerged as a bridge to transplantation, but more recently it is...