Presurgery Heart Studies
Presurgical Cardiac Evaluation
Approximately 8 million surgeries in the United States are performed on patients with known or suspected cardiac disease. Preoperative evaluation can help stratify risk.
- The Goldman index. Useful in predicting cardiac events in an unselected, random group of patients.
- Functional status. If patient can walk up stairs while carrying a load (functional status class I and II), has a low Goldman index and no known cardiac disease, there is a very low risk of cardiac complications.
- Electrocardiography. Ischemia on a resting ECG is suggestive of a worse outcome. However, exercise tolerance appears to be more important than ECG changes in predicting outcomes.
- Echocardiography. Should be reserved for those who would need an echocardiogram even if they were not having surgery, such as those with murmurs that have not been previously evaluated and those with CHF of unknown cause (diastolic versus systolic versus valvular, etc.). Stress echocardiography can be used as a replacement.
- Radionuclide ventriculography determined ejection fraction. Has not been shown to be useful in determining risk for infarction perioperatively. Note, however, that this type of datum is taken into account with clinical measures in the Goldman index (S3 gallop, JVD) and in functional status (class).
- Thallium scanning. Thallium scanning seems to be highly sensitive at selecting those who will have postoperative cardiac problems. The use of thallium scanning is restricted to those individuals who cannot exercise (therefore the functional status of these patients cannot be determined) and those whose risk cannot be determined by clinical criteria.
- History of MI. <3 weeks has 25% mortality; urgent procedure only. At 3 months 10% mortality; semiurgent procedures. At 6 months 5% mortality: elective. At 1 year, same risk as asymptomatic patient with cardiac disease.
Beta-blockers reduce perioperative ischemia in those undergoing noncardiac surgery who have known coronary artery disease or a high risk of coronary artery disease (2 or more risk factors).