Preoperative Cardiac Evaluation Jonathan Hastie January 31, 2006

Preoperative Cardiac Evaluation I. Significance of the preoperative cardiac evaluation II. Risk assessment III. Therapeutic interventions IV. Perioperative surveillance V. Summary Questions

Preoperative Cardiac Evaluation I. Significance of the preoperative cardiac evaluation II. Risk assessment III. Therapeutic interventions IV. Perioperative surveillance V. Summary Questions

Case vignette Mr Y is a 77 year old white male with a history of hypertension, coronary artery disease, and hypercholesterolemia. Mr Y is a 77 year old white male with a history of hypertension, coronary artery disease, and hypercholesterolemia. He presents to the emergency department with a three week history of worsening dyspnea and generalized weakness. He presents to the emergency department with a three week history of worsening dyspnea and generalized weakness. In the E.D., he was found to have a large, right- sided pleural effusion In the E.D., he was found to have a large, right- sided pleural effusion

Case vignette, cont. Pus was aspirated on thoracentesis. Cardiothoracic surgery was consulted, and the patient was scheduled the following day for a thoracotomy and decortication.Pus was aspirated on thoracentesis. Cardiothoracic surgery was consulted, and the patient was scheduled the following day for a thoracotomy and decortication. Immediately post-op, the patient arrived in the I.C.U. where he was noted to have ST- segment elevations.Immediately post-op, the patient arrived in the I.C.U. where he was noted to have ST- segment elevations.

Case vignette, cont. He was taken emergently for coronary angiography where two stents were placed. He was taken emergently for coronary angiography where two stents were placed.

Case vignette, cont. On returning from the cath lab, the patient had a v. fibrillation arrest and was resuscitated.On returning from the cath lab, the patient had a v. fibrillation arrest and was resuscitated. The remainder of his hospital stay was complicated by cardiogenic shock which gradually improved. He had a G.I. work-up since the empyema grew G.I. tract flora.The remainder of his hospital stay was complicated by cardiogenic shock which gradually improved. He had a G.I. work-up since the empyema grew G.I. tract flora. After his colonoscopy, the patient had a significant lower G.I. bleed. He was still on aspirin and Plavix for his coronary stents.After his colonoscopy, the patient had a significant lower G.I. bleed. He was still on aspirin and Plavix for his coronary stents.

Surgery in the United States 25 million patients undergo noncardiac surgery yearly 25 million patients undergo noncardiac surgery yearly –50,000 suffer perioperative myocardial infarction –>50% of 40,000 perioperative deaths are due to cardiac events

Surgery in the United States The Ether-dome Massachusetts General Hospital Boston, MA

Cardiovascular disease in the United States 71,000,000 American adults with some form of cardiovasular disease 71,000,000 American adults with some form of cardiovasular disease –Hypertension: 65,000,000 –Coronary artery disease: 13,200,000 –Heart failure: 5,000,000 –Stroke: 5,500,000 Source: americanheart.org, website of the American Heart Association

Cardiovascular disease in the United States Mortality Mortality –CVD accounts for 37% of all deaths in the US –Since 1900, CVD has been the number one killer in the U.S. every year save one. –2,500 Americans die from CVD daily. –Perioperative cardiac morbidity primarily related to ischemia, heart failure, or arrhythmias.

Cardiovascular disease in the United States Overheard on my cardiology elective: Overheard on my cardiology elective: “The heart is simple. In fact, the A.S.C.A.S. II trial recently showed that there are really only three kinds of problems: ischemia, congestive heart failure, and arrythmias.” “The heart is simple. In fact, the A.S.C.A.S. II trial recently showed that there are really only three kinds of problems: ischemia, congestive heart failure, and arrythmias.”

Cardiac risks of noncardiac surgery 1. Some types identify patients at higher risk for concomitant cardiac disease. -Vascular surgery -Vascular surgery 2. Cardiac stress inherent to surgery -Fluctuations in heart rate, blood pressure, intravascular volume, oxygenation intravascular volume, oxygenation -Anesthetic technique -Pain -Emergent procedures

The role of the consultant Evaluate the patient’s current medical status Evaluate the patient’s current medical status Provide clinical risk profile Provide clinical risk profile Recommend management of cardiac risk over the entire perioperative period Recommend management of cardiac risk over the entire perioperative period Treat modifiable risk factors Treat modifiable risk factors Guidelines for Perioperative Cardiovascular Evaluation for Noncardiac Surgery ACC/AHA 2002

The role of the consultant Surgery and medicine Surgery and medicine –“I think of surgery as a pill that I might prescribe. Hypertension? Prescribe a beta- blocker. Cholecystitis? Prescribe surgery.” –M.A., UTSW medicine resident

The role of the consultant Surgery and medicine Surgery and medicine –“I think general surgeons are the best doctors in the hospital. I mean, they do everything that internists do, and they operate.” –R.L. UTSW surgery resident

Guidelines for Perioperative Cardiovascular Evaluation for Noncardiac Surgery Developed by the American College of Cardiology and the American Heart Association Developed by the American College of Cardiology and the American Heart Association Revised in 2002 Revised in 2002 Largely based on observational or retrospective studies Largely based on observational or retrospective studies Few randomized prospective studies Few randomized prospective studies

Preoperative Cardiac Evaluation I. Significance of the preoperative cardiac evaluation II. Risk assessment III. Therapeutic interventions IV. Perioperative surveillance V. Summary Questions

Risk Assessment

Preoperative Cardiac Evaluation I. Significance of the preoperative cardiac evaluation II. Risk assessment -Fundamental clinical evaluation -Clinical predictors of increased risk -Surgery-specific risks -Preoperative evaluation algorithm -Preoperative testing III. Therapeutic interventions IV. Perioperative surveillance V. Summary

Assessing the situation Determine the urgency for surgery Determine the urgency for surgery Options to consider (as a team) Options to consider (as a team) –Forgo surgery –Modify the surgical procedure –Delay case (for further testing or patient optimization) –Perioperative medical therapy –Perioperative monitoring –Modification of the location of care

Fundamental clinical evaluation History History –Angina –History of myocardial infarction –Heart failure symptoms –Symptomatic arrhythmias –Pacemaker or ICD –Comorbid diseases

Fundamental clinical evaluation Functional status Functional status 1-4 METs Activities of Daily Living Walk on level ground Light housework 4-10 METs Climb stairs Heavy housework Recreational activities Strenuous sports

Fundamental clinical evaluation 1-4 METs Activities of Daily Living Walk on level ground Light housework 4-10 METs Climb stairs Heavy housework Recreational activities Strenuous sports 15 METs Intern on single intern team

Fundamental clinical evaluation Physical examination Physical examination –Uncontrolled hypertension –General appearance –Signs of CHF and valvular disease –Presence of ICD/pacemaker

Fundamental clinical evaluation Electrocardiogram Electrocardiogram –Class I: recent chest pain in a moderate-risk patient undergoing moderate-risk procedure –Class IIa: Asymptomatic person with diabetes –Class IIb Prior CABG or PTCA Prior CABG or PTCA Asymptomatic male >45 or female >55 with at least two risk factors Asymptomatic male >45 or female >55 with at least two risk factors Prior admit for cardiac causes Prior admit for cardiac causes –Class III: Routine test for asymptomatic patients with low-risk procedures

Consult etiquette Overheard on my ICU month: Overheard on my ICU month: “Did they really just consult pulmonary without getting a chest x-ray?!?” “Did they really just consult pulmonary without getting a chest x-ray?!?”

Assessing the patient Minor predictors Minor predictors –Advanced age –Abnormal ECG –Rhythm other than sinus –Low functional capacity –Uncontrolled hypertension

Assessing the patient Intermediate predictors Intermediate predictors –Mild angina pectoris (class 1 or 2) –Prior MI –Compensated or prior heart failure –Diabetes mellitus –Renal insufficiency

Assessing the patient Major predictors Major predictors –Acute or recent MI –Unstable or severe angina –Decompensated heart failure –High-grade A-V block –Severe valvular disease –Arrhythmias

Surgery-specific risks Two factors Two factors –Type of surgery –Degree of hemodynamic stress

Surgery-specific risks Low risk surgeries (<1% cardiac risk) Low risk surgeries (<1% cardiac risk) –Endoscopic procedures –Superficial biopsies –Cataracts –Breast surgery

Surgery-specific risks Intermediate risk (<5% cardiac risk) Intermediate risk (<5% cardiac risk) –Intraperitoneal and intrathoracic –Carotid endarterectomy –Head and neck –Orthopedic –Prostate

Surgery-specific risks High risk (>5% cardiac risk) High risk (>5% cardiac risk) –Emergency major operations Especially in the elderly Especially in the elderly –Aortic or major vascular surgery –Extensive operations with large volume shifts or blood loss.

Preoperative evaluation algorithm “The Road Not Taken” by Robert Frost “The Road Not Taken” by Robert Frost

Preoperative evaluation algorithm Emergent surgery  to O.R. Emergent surgery  to O.R. Coronary revascularization within five years, no symptoms  to O.R. Coronary revascularization within five years, no symptoms  to O.R. Recurrent symptoms after revascularization*, or no cardiac work-up, then evaluate Recurrent symptoms after revascularization*, or no cardiac work-up, then evaluate –Clinical predictors –Functional status –Surgical risks

Preoperative evaluation algorithm For patients with major clinical predictors undergoing non-emergent noncardiac surgery, consider delaying the surgery. For patients with major clinical predictors undergoing non-emergent noncardiac surgery, consider delaying the surgery. –Medical management –Risk factor modification –Consider coronary angiography

Preoperative evaluation algorithm Major predictors Major predictors –Acute or recent MI –Unstable or severe angina –Decompensated heart failure –High-grade A-V block –Severe valvular disease –Arrhythmias

Preoperative evaluation algorithm For patients with intermediate clinical predictors, evaluate functional status. For patients with intermediate clinical predictors, evaluate functional status. Low functional status (<4 METs) may merit further testing. Low functional status (<4 METs) may merit further testing. Moderate to good functional status (>4 mets) promps us to look at the procedure itself. Moderate to good functional status (>4 mets) promps us to look at the procedure itself.

Preoperative evaluation algorithm Intermediate predictors Intermediate predictors –Mild angina pectoris (class 1 or 2) –Prior MI –Compensated or prior heart failure –Diabetes mellitus –Renal insufficiency

Preoperative evaluation algorithm For patients with minor clinical predictors, evaluate functional status. For patients with minor clinical predictors, evaluate functional status. Moderate to good functional status indicates lowest cardiac risk for all procedures. Moderate to good functional status indicates lowest cardiac risk for all procedures. Poor functional status should prompt us to evaluate the surgical procedure. Poor functional status should prompt us to evaluate the surgical procedure. –High risk procedures may merit further testing.

Preoperative evaluation algorithm Minor predictors Minor predictors –Advanced age –Abnormal ECG –Rhythm other than sinus –Low functional capacity –Uncontrolled hypertension

Preoperative evaluation algorithm Consider noninvasive testing if two or more are present: Consider noninvasive testing if two or more are present: –Intermediate clinical predictors –Poor functional capacity –High surgical risk procedure

Preoperative testing Resting echocardiogram Resting echocardiogram Stress testing Stress testing –Exercise stress test –Chemical stress test Coronary angiography Coronary angiography

Resting echocardiogram Has not been found to be a predictor of perioperative ischemic events Has not been found to be a predictor of perioperative ischemic events Recommended in patients with current or poorly controlled heart failure Recommended in patients with current or poorly controlled heart failure Not recommended as a routine test of left ventricular function in patients without prior heart failure. Not recommended as a routine test of left ventricular function in patients without prior heart failure.

Stress testing Most useful in patients who have intermediate clinical predictors and poor functional capacity. Most useful in patients who have intermediate clinical predictors and poor functional capacity. Useful in patients at risk for CAD Useful in patients at risk for CAD Prove myocardial ischemia before revascularization Prove myocardial ischemia before revascularization

Preoperative Cardiac Evaluation I. Significance of the preoperative cardiac evaluation II. Risk assessment III. Therapeutic interventions IV. Perioperative surveillance V. Summary Questions

Coronary angiography Pre-op indications are similar to “regular” indications Pre-op indications are similar to “regular” indications –High risk of adverse outcome based on noninvasive tests

Bypass Grafting Indications for CABG before noncardiac surgery are identical to standard indications for CABG Indications for CABG before noncardiac surgery are identical to standard indications for CABG –Left main disease –Three vessel disease

Perioperative Medical Therapy Paucity of data Paucity of data Two randomized, placebo-controlled trials of perioperative beta blockers Two randomized, placebo-controlled trials of perioperative beta blockers –Reduced perioperative cardiac events –Improved 6-month survival Beta-bocker indications Beta-bocker indications –High cardiac risk patients undergoing vascular surgery –Prior usage for controling angina, symptomatic arrhythmias, or hypertension

Preoperative Cardiac Evaluation I. Significance of the preoperative cardiac evaluation II. Risk assessment III. Therapeutic interventions IV. Perioperative surveillance V. Summary Questions

Perioperative surveillance Poorly studied Poorly studied Consider… Consider… –Pulmonary Artery Catheters –Intraoperative and post-op ST- monitoring –Surveillance for Perioperative MI Repeat EKG’s Repeat EKG’s Cardiac enzymes Cardiac enzymes

Preoperative Cardiac Evaluation I. Significance of the preoperative cardiac evaluation II. Risk assessment III. Therapeutic interventions IV. Perioperative surveillance V. Summary Questions

Summary 1. Urgency for surgery? 2. Recent coronary revascularization without symptoms? 3. Recent coronary evaluation? 4. Major clinical predictors? 5. Intermediate clinical predictors? 6. Poor functional capacity & high-risk surgery?

Critique Should severe valvular stenosis be a major clinical predictor? Should severe valvular stenosis be a major clinical predictor? Do the ACC/AHA guidelines send too many people to testing? Do the ACC/AHA guidelines send too many people to testing? Does a single intermediate predictor carry as much weight as multiple intermediate predictors? Does a single intermediate predictor carry as much weight as multiple intermediate predictors? Gender effect Gender effect If patients undergo pre-op revascularization… If patients undergo pre-op revascularization… –Is the combined risk less than surgery alone? –Does revascularization significantly lower the cardiac risk? –Does recovery time unduly delay surgery?

References ACC/AHA Guideline Update on Perioperative Cardiovascular Evaluation for Noncardiac Surgery. ACC/AHA Guideline Update on Perioperative Cardiovascular Evaluation for Noncardiac Surgery. “ACC/AHA Guideline Update for Perioperative CV evaluation for Noncardiac surgery.” Anesthesia & Analgesia, Volume 94(5), May “ACC/AHA Guideline Update for Perioperative CV evaluation for Noncardiac surgery.” Anesthesia & Analgesia, Volume 94(5), May “Beta-blockers and Reduction of Cardiac Events in Noncardiac Surgery:Clinical Applications” JAMA Volume 287(11) 20 March “Beta-blockers and Reduction of Cardiac Events in Noncardiac Surgery:Clinical Applications” JAMA Volume 287(11) 20 March “Critical Review of the ACC/AHA Algorithm for Stratifying Cardiac Patients for Noncardiac Surgery.” International Anesthesiology Clinics Volume 39(4), Fall “Critical Review of the ACC/AHA Algorithm for Stratifying Cardiac Patients for Noncardiac Surgery.” International Anesthesiology Clinics Volume 39(4), Fall “Perioperative Evaluation and Managements of Patients with known or suspected CV disease…” Hurst’s The Heart McGraw-Hill, 11 th edition, New York, “Perioperative Evaluation and Managements of Patients with known or suspected CV disease…” Hurst’s The Heart McGraw-Hill, 11 th edition, New York, “Preoperative Assessment of the Patient with Cardiac Disease” Refresher Courses in Anesthesiology Volume 33(1) “Preoperative Assessment of the Patient with Cardiac Disease” Refresher Courses in Anesthesiology Volume 33(1)

Questions