Noncardiac Surgery in the Cardiac Patient

1. Noncardiac Surgeryin the Cardiac Patient David Putnam, MD Albany Medical College

2. Coronary heart disease is the most frequent cause of perioperative cardiac mortality and morbidity after noncardiac surgery

3. Noncardiac SurgeryMagnitude of the Problem • 25 million patients undergo noncardiac surgery each year in the United States • 3 million patients have clinical evidence or multiple risk factors for CAD • 4 million patients are > 65 years old • Nearly 1/3 of surgical patients are at risk for cardiovascular complications

4. Noncardiac SurgeryMagnitude of the Problem • Aging of the population • Lower threshold for performing major procedures on elderly patients • Patients with multiple comorbid illnesses

5. Noncardiac SurgeryMagnitude of the Problem • Advances in anesthesia, post-op analgesia, and surgical technique have contributed to a reduced rate of major cardiac complications • Overall risk of cardiac complications with noncardiac surgery remains low • Risk of perioperative MI: 0.1% • Risk of cardiac death: 0.4%

6. Non-Cardiac SurgeryRisk of Perioperative MI/Death • No history of ischemic heart disease: 0.1% • History of prior MI: 6%

7. Reinfarction in Post-MI Patients

8. Non-Cardiac Surgery • Although consultants are frequently asked to “clear” a patient for surgery, their role is considerably more complex

9. Noncardiac Surgery: General • Successful perioperative evaluation and treatment of cardiac patients • Teamwork and communication between • Patient • Primary Care Physician • Anesthesiologist • Surgeon • Medical Consultant

10. Preop: Role of Consultant • Assess individual patient’s risk of cardiac complications • Determine if specialized testing is appropriate • Recommend risk reduction strategies • Participate in postoperative medical management

11. Pre-Operative Cardiac Evaluation • What is the question?

12. Pre-Operative Cardiac Evaluation • Can this patient reasonably have noncardiac surgery?

13. Pre-Operative Cardiac Evaluation • Would coronary revascularization improve the long-term prognosis from a cardiac standpoint and protect the patient from adverse events during the necessary noncardiac surgery?

14. Preoperative Risk Assessment • Dripps-ASA classification • Goldman classification • ACC recommendations

15. ASA Physical Status Assessment • Class I: Healthy patient/elective operation • Class II: Patient with mild systemic disease • Class III: Severe systemic disease that limits activity but is not incapacitating • Class IV: Incapacitating systemic disease that is a constant threat to life • Class V: Moribund patient not expected to survive 24 hours with or without operation

16. Dripps-ASA ClassificationShortcomings • Subjective • Poorly reproducible in certain subsets • Elderly • Obese • Prior MI • Mild systemic diseases

17. Preoperative Cardiac AssessmentGoldman Classification • Predicts life-threatening cardiac complications or perioperative cardiac death based on presence of preoperative risk factors

18. Goldman Multifactorial Index

19. Goldman Multifactorial Index

20. Preoperative Cardiac Assessment • American College of Cardiology Recommendations JACC 1996;27:910-948

21. Noncardiac Surgery: General • Indications for further cardiac testing/treatments are the same as those in the nonoperative setting • Urgency of noncardiac surgery • Patient’s risk factors • Specific surgical considerations

22. Noncardiac Surgery: General • Preoperative testing should be limited to circumstances in which the results affect patient treatment and outcomes

23. Noncardiac Surgery: General • A conservative approach to the use of expensive tests and treatments is recommended

24. Preop Cardiac Evaluation:Considerations • Type of surgery • Functional capacity • Clinical history and physical examination

25. Noncardiac Surgery: Higher Risk Procedures • Vascular • Prolonged, complicated • Thoracic • Abdominal • Head and neck • Total hip replacement

26. Preop Cardiac Evaluation • Patients with a low functional capacity (less than 4 Mets) have a worse prognosis than patients with a good functional capacity

27. Preop Cardiac Evaluation • Clinical data from a careful history and physical examination are the critical initial steps

28. Noncardiac Surgery: Preoperative Clinical Evaluation • Identification of potentially serious cardiac disorders • Prior MI • Angina pectoris • Congestive heart failure • Symptomatic arrhythmias • Significant valvular heart disease

29. Noncardiac Surgery:Preoperative Clinical Evaluation • Preexisting manifested heart disease • Presence • Severity • Stability • Prior treatment

30. Noncardiac Surgery: Preoperative Clinical Evaluation • Always • History • Physical exam • ECG • Commonly • Echocardiogram/EST • Sometimes • Cardiac cath/MUGA scan

31. Preoperative ECG’sRecommended • Intrathoracic surgery • Intraperitoneal surgery • Aortic surgery • Neurosurgical procedure • Emergency operations

32. Preoperative ECG’sRecommended • History/physical suggesting heart disease • Men > 40-45 years old • Women > 55 years old • Systemic conditions that may be associated with unrecognized cardiac abnormality • Medications that can cause cardiac toxicity or ECG changes • Patients at risk for major electrolyte abnormalities

33. Methods of Assessing Cardiac Risk:Exercise Stress Testing • Provides substantial information about risk of perioperative MI/cardiac death • Poor functional capacity, particularly associated with myocardial ischemia predicts high risk • Gradient of increasing ischemic risk seen in association with degree of functional capacity, symptoms of ischemia, severity of ischemia, and hemodynamic instability

34. Methods of Assessing Cardiac Risk:Pharmacological Stress Testing • Dipyridamole or adenosine with thallium/sestamibi • High sensitivity/specificity for perioperative events, especially in intermediate risk group • Perioperative ischemic events appear to correlate with the magnitude of ischemia • Pharmacological stress testing involving echocardiogram is a viable option

35. Methods of Assessing Cardiac Risk:Resting LV Function • LVEF < 35% increases risk of surgery • Severe diastolic dysfunction increases risk of surgery • Evaluate LV function in presence of CHF • Probable evaluation of LV function with history of CHF or dyspnea of unknown etiology

36. Management Options after Noninvasive Testing • Intensified medical therapy • Cardiac catheterization • Cancel or delay surgery • Proceed with surgery • Coronary revascularization prior to surgery

37. Noninvasive Pre-Op Testing • The good news is that noninvasive tests are sensitive to the presence of CAD • The bad news is that the positive predictive value is poor because the likelihood of perioperative events is less than 10%

38. Methods of Assessing Cardiac Risk:Coronary Angiography • Appropriate in certain patients at high risk, including those with evidence of significant ischemia or suspicion of left main/three-vessel CAD • Indications are similar to those in the nonoperative setting • Essential that management with PTCA/CABG is a viable option

39. Coronary AngiographyClass I Indications • High-risk results during noninvasive testing • Angina pectoris unresponsive to adequate medical therapy • Most patients with unstable angina • Nondiagnostic or equivocal noninvasive test in a high-risk patient undergoing a high-risk noncardiac surgical procedure

40. Coronary AngiographyClass II Indications • Intermediate-risk results during noninvasive testing • Nondiagnostic or equivocal noninvasive test in a lower-risk patient undergoing a high-risk noncardiac surgical procedure • Urgent noncardiac surgery in a patient convalescing from acute MI • Perioperative MI

41. Noncardiac Surgery:Preoperative CABG • Indications are same as those in the nonoperative setting • Cardiac risk of CABG often exceeds that of noncardiac surgery • Rarely indicated simply to get a patient through the perioperative period

42. Noncardiac Surgery:Preoperative PTCA • No controlled trials • Several small observational studies suggest that cardiac death is infrequent in patients who have PTCA prior to noncardiac surgery • Indications are similar to those in nonoperative setting

43. Noncardiac Surgery: Emergency/Immediate Surgery • Consultant may function best by making recommendations for perioperative medical management and surveillance • Postoperative risk stratification may be appropriate for some patients who have not had such an assessment

44. Major Clinical Predictors of Increased Perioperative Cardiovascular Risk • Unstable coronary syndromes • Recent MI with evidence of ischemic risk • Unstable or severe angina • Decompensated CHF • Significant arrhythmias • High-grade AV block • Symptomatic ventricular arrhythmias • SVT’s with uncontrolled ventricular rate • Severe valvular disease

45. Noncardiac Surgery: Major Clinical Predictors • Cancel or delay surgery if surgery is elective • Many of these patients are referred for coronary angiography

46. Major Clinical Predictors

47. Intermediate Predictors on Increased Perioperative Cardiovascular Risk • Mild angina pectoris • Prior MI by history or pathological Q-waves • Compensated or prior CHF • Diabetes mellitus

48. Noncardiac Surgery:Intermediate Clinical Predictors • Consideration of functional capacity ( risk increased in patients unable to meet 4-METs of activity ) • Consideration of level of surgery-specific risk • Type of surgery • Degree of hemodynamic stress

49. Cardiac Event Risk Stratification • High Risk ( > 5% ) • Emergent major operations, particularly in the elderly • Aortic and other major vascular • Peripheral vascular • Anticipated prolonged surgical procedures associated with large fluid shifts and/or blood loss

50. Cardiac Event Risk Stratification • Intermediate Risk ( < 5% ) • Carotid endarterectomy • Head and neck • Intraperitoneal and intrathoracic • Orthopedic • Prostate