A. Introduction. Cardiovascular risk reduction strategies are an important component of perioperative medicine. Before high-sensitivity cardiac biomarkers, 2% of all patients undergoing noncardiac surgery had a major adverse cardiac event. Now, 15% of patients undergoing noncardiac surgery will experience troponin elevation (with or without ischemic symptoms or electrocardiographic changes). An elevated troponin is predictive of 30-day perioperative mortality, regardless of symptoms.
B. Medical Management to Reduce the Risk for Perioperative Cardiac Complications
a. Although several medications have been considered for perioperative risk reduction, few have shown to be associated with meaningful benefit.
i. β-Blockers. This class of drugs has been the most studied in the perioperative literature. Although results have been conflicting, the key concepts related to perioperative β-blocker use include the following:
1. Continue β-blockers throughout the entire perioperative period for patients taking them prior to surgery.
2. It is reasonable to start β-blockers before high-risk surgery in patients with intermediate-risk or high-risk myocardial ischemia noted on preoperative stress testing, or for those who have known cardiac disease or multiple cardiac risk factors (e.g., at least three risk factors on the Revised Cardiac Risk Index [RCRI]). If prescribing a β-blocker, start treatment at least a few days before surgery and titrate the dose of the medication to a goal heart rate of 50–65 beats/min, avoiding systemic hypotension. Continue therapy for at least 7 days but preferably for 30 days after surgery.
3. Do not start β-blockers on the day of surgery. A large randomized controlled trial showed an increased risk for stroke and overall mortality when high doses of β-blockers were started on the day of surgery.
b. Statins. HMG-CoA reductase inhibitors (i.e., statins) appear to have perioperative cardiovascular risk reduction qualities through their pleiotropic (i.e., non–lipid-lowering) properties. These effects likely occur within hours to days of starting a statin. Numerous trials and meta-analyses have shown significant cardiovascular risk reduction with perioperative statin use. These agents have also been shown to be safe in the perioperative setting.
i. Statins should be continued perioperatively for patients already taking them.
ii. It is reasonable to initiate statin therapy for patients undergoing vascular surgery.
iii. Statins should be considered for patients undergoing elevated risk procedures who have a traditional indication for long-term use (e.g., coronary artery disease, heart failure, diabetes mellitus, history of stroke).
c. Aspirin. A large, randomized controlled trial failed to show cardiovascular risk reduction in patients exposed to low-dose aspirin perioperatively. Furthermore, aspirin was shown to increase the risk for perioperative bleeding. Therefore, aspirin should generally be stopped 5–7 days before surgery. Exceptions include:
i. Patients with coronary stents (either bare metal or drug-eluting) should remain on low-dose aspirin perioperatively. The only exception may be some neurosurgical procedures with very high bleeding risk in patients with stents.
ii. For patients with advanced cardiovascular and/or cerebrovascular disease, continuation of low-dose aspirin perioperatively can be considered.
d. α-Agonists (e.g., clonidine). Although some older trials using an intravenous α-agonist appeared to show perioperative cardiovascular risk reduction, a recent large randomized controlled trial using clonidine failed to show any benefit.
C. Revascularization Strategies
a. Although recent coronary revascularization procedures (e.g., coronary artery bypass grafting [CABG] or percutaneous coronary intervention [PCI]) appear to offer protection for patients with ischemic heart disease in the perioperative setting, such interventions are not recommended solely for the goal of reducing risk in preparation for surgery. Therefore, with few exceptions, coronary artery revascularization should not be performed to “get the patient through surgery.”
i. The Coronary Artery Revascularization Prophylaxis (CARP) Trial was a large prospective trial that randomized patients with significant but stable coronary artery disease (at least one coronary artery with ≥70% stenosis) undergoing major vascular surgery to either medical therapy and revascularization (either CABG or PCI) or to medical therapy alone. There was no difference in postoperative myocardial infarction at 30 days as well as no difference in overall mortality at almost 3 years. Preoperative revascularization is thus not recommended for patient with significant but stable coronary artery disease.
ii. Important exceptions when preoperative coronary revascularization may be indicated include patients in whom the following diseases or conditions are present:
1. Left main coronary artery disease
2. Unstable angina
3. Acute myocardial infarction
Suggested Further Readings
Berwanger O, Le Manach Y, Suzumura EA, et al. Association between pre-operative statin use and major cardiovascular complications among patients undergoing non-cardiac surgery: the VISION study. Eur Heart J 2016;37:177–85.Find this resource:
Chopra V, Wesorick DH, Sussman JB, et al. Effect of perioperative statins on death, myocardial infarction, atrial fibrillation, and length of stay: a systematic review and meta-analysis. Arch Surg 2012;147:181–9.Find this resource:
McFalls EO, Ward HB, Moritz TE, et al. Coronary-artery revascularization before elective major vascular surgery. N Engl J Med 2004;351:2795–804.Find this resource:
Myles PS, Smith JA, Forbes A, et al. Stopping vs. continuing aspirin before coronary artery surgery. N Engl J Med 2016;374:728–37.Find this resource:
Wijeysundera DN, Duncan D, Nkonde-Price C, et al. Perioperative ® blockade in noncardiac surgery: a systematic review for the 2014 ACC/AHA guideline on perioperative cardiovascular evaluation and management of patients undergoing noncardiac surgery. Circulation 2014;130:2246.Find this resource: