Preoperative Cardiac Risk Stratification for Noncardiac Surgery Kimberly Boddicker, MD FACC Essentia Health Heart and Vascular Center 27 th Heart and Vascular Conference May 13, 2011 Objectives Summarize ACC/AHA guidelines for perioperative cardiac risk stratification. Determine who needs preoperative stress testing. Discuss who benefits from perioperative beta blocker therapy. Explain role of preoperative coronary revascularization. History Middle twentieth century began looking at clinical predictors of perioperative cardiac complications Surgery after an acute MI experienced worse outcomes Perioperative reinfarction rates correlated with the period of time elapsing from the MI Perioperative MI had high mortality 1970 s-goldman et al. developed the cardiac risk index Based on summation several weighted risk factors Assess risk independent of surgical risk 1990 s- Goldman challenged Cardiac risk is very dependent on the extent of planned surgery 1996-AHA/ACC guidelines for preoperative risk stratification for noncardiac surgery Vast amount of literature available Provide a framework for assessing cardiac risk of non-cardiac surgery in variety of patient populations and surgical situations Updated in 2002 and 2007
AHA/ACC Guidelines Original guidelines from 1996; updated in 2002 and 2007 Directed by the ACC/AHA Task Force on Practice Guidelines Expert panel from both organizations Representatives from other medical practitioner and specialty groups are included when appropriate Two outside reviewers from AHA and ACC Intended for physicians who are involved in the preoperative, operative, and postoperative care of patients undergoing noncardiac surgery Purpose Provide a framework for considering cardiac risk of surgery in variety of patient/surgical situations Purpose of preoperative evaluation is not to give medical clearance Evaluate patient s current medical status Recommendations concerning management and risk of cardiac problems over perioperative period Clinical risk profile that patient, anesthesiologist, and surgeon can use making treatment decisions Goal is the rational use of testing in an era of cost containment and optimal care of the patient Overriding theme is that intervention is rarely necessary simply to lower the risk of surgery unless such intervention is indicated irrespective of preoperative context. Approach Guideline focuses on evaluation of the patient undergoing surgery who is at risk for perioperative cardiac morbidity or mortality Patients with CAD or new signs/symptoms of CAD Asymptomatic patient 50 years of age Revised cardiac risk index occurred in this population Preoperative evaluation must be tailored to the circumstances prompting the evaluation and to the nature of the surgical illness In patient in whom coronary revascularization is not an option, noninvasive stress test may not be necessary Evaluation may lead to a variety of responses, including cancellation of an elective procedure
The Assessment History Identify serious cardiac conditions Symptomatic change in patient with established cardiac disease Pacemakers/ICD Co morbid Diseases Patients functional capacity Physical Examination Comprehensive cardiovascular examination Hematocrit < 28% are associated with an increased incidence of perioperative ischemia and complications Additional testing recommended if the information obtained will result in a change Type of surgical procedure performed Change in medical therapy or monitoring during/after procedure Postponement of surgery until the cardiac condition can be corrected/stabilized Guideline Changes Serious Cardiac Conditions Revised Cardiac Risk Index Not incorporated into recommendations Eagle et al.. JACC 39(3):542-53. 2002 Serious Cardiac Conditions Major predictors-mandate intensive management, may result in delay or cancellation of surgery unless emergent
Revised Cardiac Risk Index One of the most widely used risk indices History, PE, and ECG usually provides the consultant with sufficient data to estimate cardiac risk Six independent risk correlates were identified by Lee et al. Ischemic heart disease CHF CVD High-risk surgery Preoperative insulin treatment for diabetes mellitus Creatinine > 2.0 Given increased use of Revised CRI, new guidelines now use the CRI to replace intermediate clinical predictors Intermediate Risk Patients History of heart disease History of compensated or prior heart failure History of cerebrovascular disease Diabetes mellitus Renal insufficiency Intermediate predictorswell-validated markers of enhanced risk of cardiac complications, justify careful assessment of patient s current status Minor Risk Predictors Recognized markers for cardiovascular disease that have not been proven to independently increase perioperative risk Advanced age (> 70 y.o.) Abnormal ECG Rhythm other than sinus Uncontrolled HTN Presence of multiple minor predictors might lead to a higher suspicion of CAD but not incorporated into the recommendations for treatment
Functional Status Surgical Risk 2007 Guidelines
Cardiac Evaluation and Care Algorithm for Noncardiac Surgery Step 1 Need for emergency noncardiac surgery? N o Ye (Class si, LOE C) Operating room Perioperative surveillance and postoperative risk stratification and risk factor managemen t Step 2 Active cardiac conditions * Yes (Class I, LOE B) Evaluate and treat per ACC/AHA guidelines Consider operating room N o Step 3 Low risk surgery N o Yes (Class I, LOE B) Proceed with planned surgery Step 4 Functional capacity greater than or equal to 4 METs without symptoms. Yes (Class IIa, LOE B) Proceed with planned surgery Step 5 No or unknown 3 or more clinical risk factors? Vascular Surgery Class IIa, LOE B Intermediate risk surgery Vascular Surgery 1-2 clinical risk factors? Intermediate risk surgery No clinical risk factors? Class I LOE B Consider testing if it will change management Proceed with planned surgery with HR control (Class IIa, LOE B) or consider noninvasive testing (Class IIb LOE B) if it will change with management Proceed with planned surgery Bonow et al. JACC. 46(6):1144-78. 2005
Noninvasive Stress Testing I IIa IIb III Patients with active cardiac conditions in whom noncardiac surgery is planned should be evaluated and treated per ACC/AHA guidelines before noncardiac surgery. I IIa IIb III Noninvasive stress testing of patients with 3 or more clinical risk factors and poor functional capacity (< 4 METs) who require vascular surgery is reasonable if it will change management. Noninvasive Stress Testing I IIa IIb III Noninvasive stress testing may be considered for patients: With at least 1 to 2 clinical risk factors and poor functional capacity (less than 4 METs) who require intermediate-risk or vascular surgery if it will change management. I IIa IIb III Noninvasive testing is not useful for patients: With no clinical risk factors undergoing intermediate-risk noncardiac surgery. Undergoing low-risk noncardiac surgery. Noninvasive Evaluation of Left Ventricular Function
Preoperative Resting 12-Lead ECG Beta Blocker Therapy Recently published focused update on beta blocker therapy Last decade has explored various aspects of BB therapy Conflicting observations of benefit Observation that may actually be harmful in low risk patient populations Since publication of ACC/AHA focused update on perioperative BB therapy, several randomized trials have been published that have not demonstrated as much efficacy Many randomized trials are small Weight of evidence in aggregate suggests a benefit of perioperative BB in high-risk patients Suggested potential benefits Reduction in perioperative ischemia on monitoring Reduction in MI and death, even up to 6 months Current studies suggest BB reduce ischemia and may reduce risk of MI and death in patients with known CAD Evidence suggests, when possible beta blockers should be dosed: Several days or weeks before elective surgery Dose titrated to achieve resting HR 50-60 Maintained perioperatively to maintain HR <80 Higher risk patients more likely to receive benefits Longer acting beta blockers may provide more benefit Limitations in Perioperative Beta Blocker Literature Few randomized trials of medical therapy Few randomized trials have examined titration of medications to effect Most studies are inadequately powered Studies to determine the role in intermediate and low risk populations needed Studies to determine the optimal type are needed No studies have addressed care-delivery mechanisms in perioperative setting How, when, by whom administered
Preoperative Revascularization Indications for preoperative surgical revascularization are those recommended by ACC/AHA 2004 guideline update for CABG Usually reserved for active symptoms, severe 3V disease, LM disease Literature suggest that PCI before noncardiac surgery is of no value in preventing perioperative cardiac events, except in those patients in whom PCI is independently indicated Most studies involved high-risk patients undergoing noncardiac surgery Routine revascularization in patients with stable cardiac symptoms does not alter risk of death or MI DECREASE-V pilot study found no difference in combined outcomes of death or MI High-risk patients undergoing vascular surgery Best medical therapy and revascularization vs. best medical therapy No difference at 30 days or 1 year High incidence of cardiac event in this high risk cohort Management of Patients with Recent PCI Noncardiac surgery in a patient with recent PCI presents challenges regarding dual-antiplatelet agents Bare-metal stent thrombosis is most common in first 2 weeks after stent placement Very rare (<0.1%) more than 4 weeks after placement Thrombosis of DES may occur late and has been reported up to 1.5 years after implantation, particularly in the context of discontinuation of antiplatelet agents before noncardiac surgery Premature discontinuation of dual-antiplatelet therapy increases risk of stent thrombosis, MI and/or death Elective procedures with significant risk of bleeding should be deferred until patients have completed appropriate course of thienopyridine therapy If procedure necessary and thienopyridine therapy must be stopped, continued aspirin use recommended with reinstitution of thienopyridine after surgery No evidence that warfarin, antithrombotics, or glycoprotein IIb/IIIa agents will reduce risk of stent thrombosis after discontinuation of oral antiplatelet agents
Updated Changes Updated AHA/ACC guidelines 2007 Focus on appropriate perioperative beta blocker use Defining groups and procedures where most benefit Redefine use of noninvasive stress evaluations Testing can delay surgery even up to 2-4 weeks Recent studies suggest a nonsignificant difference in cardiac outcomes in intermediate risk patients with vascular surgery Beta blocker therapy may be beneficial Limited role of revascularization Only appropriate in a very small subgroup of high-risk patients Special perioperative considerations for patients on dualantiplatelet therapy Conclusions Preoperative cardiac evaluation prior to noncardiac surgery has become a subspecialized area in the literature. Large amount of literature with conflicting recommendations can make assessment difficult Difficulties come as preoperative evaluation tries to detect a potential disease not an actual one Current ACC/AHA guidelines developed to help provide a framework for considering cardiac risk of surgery in variety of patient/surgical situations Preoperative assessment allows for current evaluation of patient cardiac status and opportunity optimize therapy Beta blocker therapy can reduce perioperative ischemia, death and MI in certain patient populations Implementation of guidelines have led to more appropriate use of preoperative stress and beta blocker therapy while preserving low rate of cardiac complications Current guidelines focus on less noninvasive testing in intermediate risk patients and continued focus on beta blocker therapy Limited role for cardiac revascularization prior to noncardiac surgery
References Barak, M. et al. ACC/AHA guidelines for preoperative cardiovascular evaluation for noncardiac surgery: a critical point of view. Clin. Cardiol. 29:195-8. 2006 Eagle, KA. et al. ACC/AHA guideline update on perioperative cardiovascular evaluation for noncardiac surgery. JACC 39(3):542-53. 2002 Palda, VA. et al. Guidelines for assessing and managing the perioperative risk from coronary artery disease associated with major noncardiac surgery. Ann Intern Med. 127(4): 309-12. 1997 Fleisher, LA et al. ACC/AHA 2007 guidelines on perioperative cardiovascular evaluation and care for noncardiac surgery: executive summary. JACC. 50(17):1707-32. 2007. Fleisher, LA. et al. ACC/AHA 2006 guideline update on perioperative cardiovascular evaluation for noncardiac surgery: focused update on perioperative beta-blocker therapy. JACC. 47(11):2343-55. 2006 Stevens et al.. Anesth Analg. 2003(7):623-33 Gordon, AJ. et al. Guideline chaos: conflicting recommendations for preoperative cardiac assessment. Am J Cardiol. 91:1299-1303. 2003. Almanaseer, Y. et al. Implementation of the ACC/AHA guidelines for preoperative cardiac risk assessment in a general medicine preoperative clinic: improving efficiency and preserving outcomes. Cardiology. 103:24-9. 2005. Poldermans, D. et al. Should major vascular surgery be delayed because of preoperative cardiac testing in intermediate-risk patients receiving beta-blocker therapy with tight heart rate control? JACC. 48(5):964-9. 2006. Lindenauer, PK. et al. Perioperative beta-blocker therapy and mortality after major noncardiac surgery. NEJM. 353:349-61. 2005. McFalls, EO. et al. Coronary-artery revascularization before elective major vascular surgery. NEJM. 351:2795-804. 2004. Boschert, S. Cardiac testing before surgery to be challenged. Cardiology News. February 2007 www.acc.org