Assessing Cardiac Risk in Noncardiac Surgery Murali Sivarajan, M.D. Professor University of Washington Seattle, Washington
Disclosure None. I have no conflicts of interest, financial or otherwise.
CME Objectives List the risk factors identified in the Revised Cardiac Risk Index (RCRI) and by the National Surgical Quality Improvement Program (NSQIP) database. Develop risk profiles, i.e., state the probability of developing complications, using hypothetical cases. Using hypothetical cases and the American College of Cardiology-American Heart Association algorithm for Perioperative Cardiac Assessment, develop consultation/treatment plan(s).
Cardiac Diseases Approximately 7% of surgical patients have cardiac disease. 66% of Cardiac Patients for Noncardiac Surgery have Coronary Artery Disease. Valvular Heart Disease, Congenital Heart Disease, Cardiomyopathy etc comprise the remainder.
Major Adverse Cardiac Events (MACE) Perioperative Myocardial Infarction Cardiogenic Pulmonary Edema Life threatening Arrhythmias Death from Cardiac Causes
Mortality after a perioperative MI is high, probably ~ 30%
Increased Pulmonary and Cardiac complications with lower (or poorer ) ASA Physical Status Higher incidence of Perioperative Myocardial Infarction and Cardiac Death in patients with previous infarction (Tarhan et al. JAMA 1972;220:1451)
Cardiac Risk Index Score (CRIS) S3 Gallop or JVD 11 points MI in the previous 6 months 10 points Rhythm other than sinus 7 points More than 5 PVCs/min 7 points Age > 70 years 5 points Emergency/Major operation 4 points Aortic Stenosis 3 points Poor medical condition 3 points (Goldman et al N Engl J Med 1977;297:845)
CRIS underestimates complications in aortic surgery patients and overestimates complications in minor surgery patients (Detsky et al. J Gen Inter Med 1986;1:211) (Leppo et al. J Am Coll Cardiol 1987;9:269) (Schein et al. N Engl J Med 2000;342:168)
Revised Cardiac Risk Index (RCRI) Derived from 2893 patients Validated in 1422 patients Thoracic 13% Abdominal 13% AAA 5% Other 69% (Lee et al. Circulation 1999;100:1043)
Revised Cardiac Risk Index (RCRI) High Risk Surgery Ischemic Heart Disease History of CHF History Cerebrovascular Disease Insulin Dependent Diabetes Preoperative Serum Creatinine > 2 mg/dl (Lee et al. Circulation 1999;100:1043)
Revised Cardiac Risk Index (RCRI) Class I (no risk factors) 0.4 Class II (1 risk factor) 0.9 Class III ( 2 risk factors) 6.6 Class IV ( 3 or more) 11 Complication Rate (%) (Lee et al. Circulation 1999;100:1043)
Perioperative Myocardial Infarction or Cardiac Arrest Risk Calculator from NSQIP* 1. Age 2. ASA Class 3. Serum Creatinine > 1.5 mg/dl 4. Functional Status 3 states 5. Surgical Procedure 21 different types (Gupta PK et al. Circulation 2011;124:381-387) * National Surgical Quality Improvement Program
Perioperative Myocardial Infarction or Cardiac Arrest Risk Calculator from NSQIP* <http://www.surgicalriskcalculator.com/miorcardiacarrest> (Gupta PK et al. Circulation 2011;124:381-387) * National Surgical Quality Improvement Program
Myocardial Ischemia Postop MI Mortality Stable Angina < 1% < 1% Unstable Angina, Acute MI < 30 days 32% 14% Recent MI 31 to 90 days 18% 11.5% Recent MI 91 to 180 days 5.9% 10% (Shah et al. Anesth Analg 1990;70:240) (Livhits et al. Ann Surg 2011;253:857)
Congestive Heart Failure Postoperative Pulmonary Edema 15% in uncompensated CHF 5% in well compensated CHF (Shah et al. Anesth Analg 1990;70:240) In elderly patients with CHF undergoing major surgery, 30 day postop mortality is 10% (Van Diepen et al. Circulation 2011;124:289)
Valvular Heart Diseases Symptomatic valvular lesions pose higher risk of postoperative myocardial infarction or heart failure Asymptomatic valvular lesions, even if severe by echocardiographic criteria, pose only minimally increased risk of postoperative cardiac complications. (2014 ACC/AHA Guidelines. J Am Coll Cardiol 2014;64:e77-157)
Pulmonary Hypertension In patients with pulmonary arterial hypertension, postoperative mortality is 4 to 26% And postoperative morbidity is 6 to 42% (Ramakrishna et al. J Am Coll Cardiol 2005;45:1691) (Lai et al. Br J Anaesth 2007;99:184)
Type of Surgery Complication Rate Low Risk Surgery (cataract, plastic, breast) Intermediate Risk Surgery (thoracic, abdominal, major orthopedic) High Risk Surgery (Aortic, trauma, emergency, sepsis) < 1% < 5% > 5% (2007 ACC/AHA Guidelines. J Am Coll Cardiol 2007;50:e241)
History and Physical Examination To determine Functional Status Routine Lab test
- Climbing 2 flights of stairs without stopping requires ~ 5 METS - How about walking 2 city blocks?
6 Minute Walk Test 1 MET ~ 100 meters
6 Minute Walk Test Normal adult males can walk 600 m (range 400-800 m) in 6 minutes. One Year mortality in patients with heart disease who walk < 300 m is 10% and in those who walk > 600 m is 3%; in the same groups hospitalization for heart failure is 22% vs 2% (Bittner et al. JAMA 1993;270:1702) (Faggiano V. Eur J Heart Fail 2004;6:687)
Role of Additional Testing? To identify patients who might benefit from coronary revascularization
Echocardiography It is inappropriate to perform echocardiography (for screening purposes) in some one without symptoms or signs of cardiovascular disease (ACC/ASE/ACC Appropriate Use Criteria. J Am Coll Cardiol 2011;57:1126)
2014 ACC/AHA Guideline for Perioperative Cardiovascular Evaluation for Noncardiac Surgery (J Am Coll Cardiol 2014;64:e77)
Step 1 Scheduled for emergency surgery? If YES, stratify risk and proceed to surgery. Institute intensive monitoring and treatment of complications If NO, go to Step 2 (2014 ACC/AHA Guidelines. J Am Coll Cardiol 2014;64:e77)
Step 2 Does the patient have Acute Coronary Syndrome (myocardial infarction, unstable angina)? If YES, treat condition before surgery If NO, go to Step 3 (2014 ACC/AHA Guidelines. J Am Coll Cardiol 2014;64:e77)
Step 3 Is it low risk surgery? Complication rate < 1%? If YES, go to Step 4: No further testing needed; proceed to surgery If NO, proceed to Step 5 (2014 ACC/AHA Guidelines. J Am Coll Cardiol 2014;64:e77)
Step 5 Elevated risk surgery. Complication rate > 1% Is functional capacity > 4 METS? If YES, No further testing needed; proceed to surgery If NO, go to Step 6 (2014 ACC/AHA Guidelines. J Am Coll Cardiol 2014;64:e77)
Step 6 Poor functional capacity (< 4 METS) or unknown functional capacity. Will further testing impact decision making or postoperative care? If NO, proceed with surgery If YES, go to Step 7 (2014 ACC/AHA Guidelines. J Am Coll Cardiol 2014;64:e77)
Step 7 Perform Pharmacologic Stress Testing to detect reversible myocardial ischemia If NORMAL (no reversible ischemia), proceed to surgery If ABNORMAL (reversible ischemia present), perform coronary revascularization before surgery (2014 ACC/AHA Guidelines. J Am Coll Cardiol 2014;64:e77)
Perfusion Studies Alternative test for patients who can not exercise Identifies regions of reversible ischemia
Cardiac catheterization to determine feasibility of Angioplasty or CABG surgery before noncardiac surgery
CABG Before Noncardiac Surgery Risk of cardiac complications due to CABG surgery has to be taken into account
CABG Before Noncardiac Surgery CABG before vascular surgery reduces overall mortality only when the risk of vascular surgery exceeds the risk of CABG (Mason et al. JAMA 1995;27 3:1919)
Coronary Artery Revascularization Prophylaxis (CARP) Study In patients with stable angina and two vessel CAD, CABG or Angioplasty before abdominal aortic surgery compared to medical therapy offered no benefits. (McFall EO et al. N Engl J Med 2004;351:2795-2804)
CABG before Major Vascular Surgery CABG before major vascular surgery may offer benefits only in patients in whom CABG itself offers significant survival benefits: Left main disease 3 vessel CAD with ischemic LV dysfunction Unstable angina or acute coronary syndrome
Angioplasty Before Noncardiac Surgery Does not seem to offer immediate protection. May increase near-term complications
Angioplasty Before Noncardiac Surgery Eight out of 40 patients who underwent high-risk noncardiac surgery with in 14 days of angioplasty died. Stent thrombosis was the major cause (Kaluza et al. J Am Coll Cardiol 2000;35:1288)
Angioplasty Before Noncardiac Surgery Dual platelet inhibition therapy should be continued for: 4-6 weeks after bare metal stents 6 months to 1year after drug eluting stents (2014 ACC/AHA Guidelines. J Am Coll Cardiol 2014;64:e77)
Summary History and clinical exam to derive functional capacity and routine labs to determine risk of complications are sufficient in most patients. Low Risk is complication rate < 1% High Risk is complication rate > 1%
Summary Revised Cardiac Risk Index (RCRI) High Risk Surgery Ischemic Heart Disease History of CHF History Cerebrovascular Disease Insulin Dependent Diabetes Preoperative Serum Creatinine > 2 mg/dl (Lee et al. Circulation 1999;100:1043)
Summary Perioperative Myocardial Infarction or Cardiac Arrest Risk Calculator from NSQIP* <http://www.surgicalriskmcalculator.com/miorcardiacarrest> (Gupta PK et al. Circulation 2011;124:381-387) * National Surgical Quality Improvement Program
Summary Additional testing (perfusion and catheterization studies) are needed only in a small subset of patients. Beta blockers and statins should be continued in patients who are already receiving them. Beta blockers should not be started on the day of surgery; if needed, should be started days before surgery to monitor response
Summary CABG before major vascular surgery is indicated only if there is survival benefit from CABG. Elective Surgery should be delayed for 4 weeks after bare metal stent and for up to one year after drug eluting stent.
Thank You
Question 1 From the list of risk factors listed below, circle the six (6) risk factors that are identified in the Revised Cardiac Risk Index (RCRI): Coronary Artery Disease Hypertension Cerebrovascular disease Smoking Chronic Obstructive Pulmonary Disease (FEV1/FVC < 50% predicted) Chronic Kidney Disease with serum creatinine > 2mg/dL Obesity Insulin dependent diabetes mellitus Alcoholic cirrhosis of the liver with ascites and esophageal varices History of congestive heart failure Atrial fibrillation Open abdominal or thoracic surgery or vascular surgery above the inguinal ligament
Question 2 The risk or the probability of postoperative cardiac complication in a surgical patient who has 3 or more of the risk factors identified in the Revised Cardiac Risk Index (RCRI) is approximately: A. 5% B. 10% C. 15% D. 20%
Question 3 A 68-year-old male was found to have a an abdominal aortic aneurysm (AAA) measuring 6 cm in diameter and he has been advised by a vascular surgeon to have an open resection of the AAA and replacement with an aorto-iliac bifurcation graft. He has stable angina precipitated by climbing 3 flights of stairs relieved by rest or sublingual nitroglycerin. He also has hypertension. He takes metoprolol and hydrochlorthiazide. Echocardiogram shows left ventricular hypertrophy with an ejection fraction = 65%. Cardiac catheterization reveals 90% stenosis of distal left anterior descending coronary artery and 80% stenosis of mid circumflex coronary artery. The best line of treatment is: A. Coronary artery bypass grafting (CABG) and AAA resection and repair at the same sitting B. CABG followed weeks later by AAA resection and repair. C. Percutaneous coronary intervention with stents followed weeks later by AAA resection and repair D. AAA resection and repair within days after medical optimization.