Cardiovascular risk stratification prior to non-cardiac surgery

Abstract

Cardiovascular perioperative risk assessment in non-cardiac patients is an important subject in clinical practice, with a great impact in global health costs worldwide. It has been defined as the risk of a cardiac event occurring in non-cardiac surgeries. There are national and international society guidelines with relatively similar recommendations; however, some controversies and different approaches exist depending on the available health systems, resources, and/or local experience.

Several surgical procedures imply a significant cardiovascular risk to patients with coronary artery disease (CAD), in some of them unknown or with silent presentation, common in diabetics. Patients with peripheral arterial vascular disease are more prone to present CAD and present higher perioperative risks, most prominent in major non-cardiac surgical procedures. There is a strong need to be aware of these conditions in all patients prior to surgical interventions obtaining adequate and standardized risk stratification. The risks are inherent to the required anesthesia procedures and interventional times, fluid requirements, and other issues. Then, clinical and surgical risks should always be considered in every case.

In general, it is necessary to know the urgency of the procedure, its inherited cardiovascular risk (low, intermediate, or high), and the individual clinical and surgical risks, including different variables such as age, general condition, comorbidities, cardiopulmonary symptoms, kidney function, medications, and electrocardiogram (EKG) abnormalities.

In this chapter, we will review the current use of non-invasive techniques to assess cardiovascular risk, mainly with radionuclide myocardial perfusion imaging (MPI), prior to non-cardiac surgery. The high negative predictive value of MPI is well established. Cardiac imaging is preferred in cases with intermediate to high clinical risk.

A concise comparison with other available methods to evaluate this type of risk will be also addressed. Non-invasive stress testing indications are clearly depicted in the most latter perioperative risk assessment guidelines. We will give special emphasis to appropriate indications of radionuclide stress testing and safety including vulnerable populations, such as diabetics, chronic failure patients, organ transplant candidates, and elderly population.