What is the evidence for preoperative cardiac stress testing in patients prior to surgery?

From the Guidelines

Preoperative cardiac stress testing is not recommended for routine use in all surgical patients, and should only be considered in patients with high cardiac risk factors undergoing high-risk procedures, as stated in the 2024 AHA/ACC guideline 1.

Key Points

• The evidence supports stress testing in patients with poor functional capacity (unable to climb two flights of stairs or perform 4 METs of activity) 1.
• Multiple cardiac risk factors (such as coronary artery disease, heart failure, cerebrovascular disease, diabetes, or renal insufficiency) and high-risk surgeries (vascular, major thoracic, or prolonged abdominal procedures) also warrant consideration for stress testing 1.
• The most common stress tests include exercise electrocardiography, stress echocardiography, and nuclear myocardial perfusion imaging, which help identify myocardial ischemia, assess ventricular function, and determine perioperative cardiac risk 1.
• However, unnecessary testing in low-risk patients can lead to surgical delays, increased costs, and potential harm from false positive results or additional invasive procedures, as noted in the 2024 AHA/ACC guideline 1.

Rationale

The 2024 AHA/ACC guideline 1 emphasizes that preoperative stress testing should not be performed in patients with adequate functional capacity, and that routine preoperative stress testing is not recommended in low-risk patients or in stable patients undergoing low-risk noncardiac surgery. The guideline also notes that the benefits of preoperative revascularization appear to be limited, and that routine preoperative stress testing should not be performed in patients with adequate functional capacity 1. In terms of which pharmacological test to use, there are no RCTs comparing DSE with pharmacological MPI perioperatively, but local expertise in performing pharmacological stress testing should be considered in decisions about which pharmacological stress test to use 1.

Clinical Implications

Preoperative cardiac stress testing should be selectively employed in patients with high cardiac risk factors undergoing high-risk procedures, as stated in the 2024 AHA/ACC guideline 1. Patients with significant findings may benefit from preoperative interventions such as medication optimization (beta-blockers, statins), delay of elective surgery, or coronary revascularization in select cases. However, the goal of preoperative testing for ischemia is not to identify undiagnosed CAD but to identify patients for whom revascularization is believed to improve clinical outcomes, specifically those with left main disease or severe multivessel disease with a reduced LVEF, as noted in the 2024 AHA/ACC guideline 1.

From the Research

Preoperative Cardiac Stress Testing

• The evidence for preoperative cardiac stress testing in patients prior to surgery is limited and suggests that it should be reserved for patients with suspicion of a myocardium at risk of ischemia 2.
• Noninvasive stress testing is widely used to help predict risk of perioperative complications, but its poor predictive power hampers its usefulness 3.
• Stress testing may be considered in patients at higher risk (determined by the inability to climb ≥2 flights of stairs, which is <4 metabolic equivalent tasks) if the results from the testing would change the perioperative medical, anesthesia, or surgical approaches 4.
• A systematic review and meta-analysis found that the current body of evidence is insufficient to derive a definitive conclusion as to whether stress testing leads to reduced peri-operative mortality 5.

Indications for Preoperative Cardiac Stress Testing

• Patients with low clinical risk factors and good functional status, undergoing a low or intermediate risk surgery, have an excellent prognosis and may proceed to surgery without further delay 3.
• Patients requiring urgent surgery should proceed immediately, since the consequences of delay usually outweigh the benefits of preoperative risk assessment 3.
• Elective surgery should be indefinitely deferred for those patients with unstable coronary syndromes, since consequences of the cardiac disease usually negate the benefits of surgery 3.
• Comprehensive history, physical examination, and assessment of functional capacity during daily life should be performed prior to noncardiac surgery to assess cardiovascular risk 4.

Risk Assessment and Management

• Risk calculators, such as the Revised Cardiac Risk Index, identify individuals with low risk (<1%) and higher risk (≥1%) for perioperative major adverse cardiovascular events during the surgical hospital admission or within 30 days of surgery 4.
• Cardiovascular testing is rarely indicated in patients at low risk for major adverse cardiovascular events 4.
• Statins are associated with fewer postoperative cardiovascular complications and lower mortality in observational studies, and should be considered preoperatively in patients with atherosclerotic cardiovascular disease undergoing vascular surgery 4.
• High-dose β-blockers administered 2 to 4 hours prior to surgery are associated with a higher risk of stroke and mortality, and should not be routinely used 4.