Preoperative Optimization of the Heart Failure Patient Undergoing Cardiac Surgery

Abstract

Heart failure patients who undergo cardiac surgery are exposed to significant perioperative complications and high mortality. We herein review the literature concerning preoperative optimization of these patients. Salient findings are that end-organ dysfunction and medication should be optimized before surgery. Specifically: (1) reversible causes of anemia should be treated and a preoperative hemoglobin level of 100 g/L obtained; (2) renal function and volume status should be optimized; (3) liver function must be carefully evaluated; (4) nutritional status should be assessed and cachexia treated to achieve a preoperative albumin level of at least 30 g/L and a body mass index > 20; and (5) medication adjustments performed, such as withholding inhibitors of the renin-angiotensin-aldosterone system before surgery and continuing, but not starting, β-blockers. Levels of natriuretic peptides (brain natriuretic peptide [BNP] and N-terminal proBNP) provide additional prognostic value and therefore should be measured. In addition, individual patient's risk should be objectively assessed using standard formulas such as the EuroSCORE-II or Society of Thoracic Surgeons risk scores, which are simple and validated for various cardiac surgeries, including left ventricular assist device implantation. When patients are identified as high risk, preoperative hemodynamic optimization might be achieved with the insertion of a pulmonary artery catheter and hemodynamic-based tailored therapy. Finally, a prophylactic intra-aortic balloon pump might be considered in certain circumstances to decrease morbidity and even mortality, like in some high risk heart failure patients who undergo cardiac surgery, whereas routine preoperative inotropes are not recommended and should be reserved for patients in shock, except maybe for levosimendan.