Chapter 69: Prophylactic Cardiac Risk Reduction

INTRODUCTION

Cardiovascular complications are the most common cause of perioperative morbidity and mortality in patients undergoing noncardiac surgery. For elective surgery, the application of evidence-based strategies can significantly reduce the risk of adverse cardiovascular events in high-risk patients. The following guidelines, developed by the American College of Cardiology (ACC) and the American Heart Association (AHA), are based on an extensive review of the literature. The recommendations are based on the strength of the clinical evidence and are considered the standard for the perioperative management of cardiac patients.

CORONARY REVASCULARIZATION

Preoperative coronary revascularization with coronary artery bypass grafting (CABG) or percutaneous coronary intervention (PCI) can reduce the risk of cardiac morbidity and mortality in patients who meet the following criteria:

1. Stable angina—who have significant left main coronary artery stenosis

2. Stable angina—who have three-vessel disease

3. Two-vessel disease with significant proximal left anterior descending (LAD) stenosis and either ejection fraction less than 0.50 or demonstrable ischemia on noninvasive testing

4. High-risk unstable angina or non–ST-segment elevation MI

5. Acute ST-elevation MI

The usefulness of preoperative coronary revascularization is not well established in high-risk ischemic patients with abnormal dobutamine stress echocardiograph, and it is not recommended that routine prophylactic coronary revascularization be performed in patients with stable coronary artery disease before noncardiac surgery.

Managing patients with recently placed coronary stents can be broken down into two groups. (a) For patients in whom coronary revascularization with PCI is appropriate for mitigation of cardiac symptoms and who need elective noncardiac surgery in the subsequent 12 months, a strategy of balloon angioplasty or bare-metal stent placement followed by 4–6 weeks of dual-antiplatelet therapy is probably indicated. (b) For patients who received drug-eluting coronary stents and who must undergo urgent surgical procedures that mandate the discontinuation of thienopyridine therapy, it is reasonable to continue aspirin if at all possible and restart thienopyridine as soon as possible.

Medical Management

Medical therapies for cardiac patients include beta blockers, statins, aspirin, calcium channel blockers, and insulin.

A. Beta-Blockers

Class I recommendations:

1. Beta-blockers should be continued in patients undergoing surgery, who are currently receiving beta blockers to treat angina, symptomatic arrhythmias, hypertension, or other ACC/AHA Class I guideline indications.

2. Beta-blockers should be given to patients undergoing vascular surgery who are at high cardiac risk owing to the finding of ischemia on preoperative testing.

Class IIa recommendations: Beta-blockers are recommended for:

1. Patients undergoing vascular surgery in whom the preoperative assessment identifies coronary heart disease (CHD).

2. Patients in whom preoperative assessment for vascular surgery identifies high cardiac risk, as defined by the presence of more than one clinical risk factor.

3. Patients in whom preoperative assessment identifies CHD or high cardiac risk, as defined by the presence of more than one clinical risk factor, who are undergoing ...