Perioperative MI.ppt


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Perioperative MI.ppt

  1. 1. Perioperative myocardial infarction after noncardiac surgery <ul><li>INCIDENCE </li></ul><ul><li>5.8% overall risk of postoperative cardiac death or major cardiac complications in patients undergoing major noncardiac surgical procedures [Goldman et al. NEJM 1977]. </li></ul><ul><li>~3% risk of perioperative MI in patients undergoing nonoperative surgery [Deveraux et al., CMAJ 2005] </li></ul><ul><li>Risk of 1.4%, 3.2%, to 6.9% in successive surgical patients [Mangano et al., NEJM 1995]. </li></ul><ul><li>1.8% incidence of perioperative MI in men over the age of 40, but ranging from 0% to 0.8% to 4.1% [Ashton et al., Ann Intern Med 1993]. </li></ul><ul><li>High risk patients experienced perioperative MI 3.0% of the time [Mangano et al. NEJM 1990] </li></ul><ul><li>4.7-5.6% incidence in patients with known coronary disease [Shah et al. Anesth Analg 1990; Badner et al. Anesthesiology 1998]. </li></ul>
  2. 2. <ul><li>DIAGNOSIS </li></ul><ul><li>14% patients have chest pain </li></ul><ul><li>53% have a sign or symptom that triggers consideration for perioperative MI </li></ul><ul><li>Cardiac biomarkers </li></ul>
  3. 3. Revised Goldman Cardiac Risk Index (RCRI) <ul><li>Independent predictors of major cardiac complications: </li></ul><ul><li>High-risk operation (intraperitoneal, intrathoracic, suprainguinal vascular procedures) </li></ul><ul><li>Hx of ischemic heart disease </li></ul><ul><li>Hx of heart failure </li></ul><ul><li>Hx of cerebrovascular disease </li></ul><ul><li>DM requiring insulin </li></ul><ul><li>Preoperative serum creatinine > 2.0 mg/dL </li></ul>
  4. 4. <ul><li>Deveraux et al., CMAJ 2005: </li></ul><ul><li>Rate of cardiac death MI, and cardiac arrest: </li></ul><ul><li>0 RF: 0.4% [0.1-0.8] </li></ul><ul><li>1 RF: 1.0% [0.5-1.4] </li></ul><ul><li>2 RF: 2.4% [1.3-3.5] </li></ul><ul><li>3+RF: 5.4% [2.8-7.9] </li></ul>Revised Goldman Cardiac Risk Index (RCRI)
  5. 5. <ul><li>Auerbach et al. Circulation 2006: </li></ul><ul><li>Rate of cardiac death, MI, cardiac arrest or VF, pulmonary edema, complete heart block, without or with perioperative beta-blocker treatment: </li></ul><ul><li>0 RF: 0.4-1.0% vs. <1.0% </li></ul><ul><li>1-2 RF: 2.2-6.6% vs. 0.8-1.6% </li></ul><ul><li>3+ RF: >9% vs. >3% </li></ul>Revised Goldman Cardiac Risk Index (RCRI)
  6. 6. Diagnosis of perioperative MI after noncardiac surgery <ul><li>No standard diagnostic criteria. Diagnosis complicated by lack of symptomatic presentation in about half of patients with perioperative MI. </li></ul><ul><li>Deveraux et al, CMAJ 2005 proposed the following diagnostic criteria: </li></ul><ul><li>1) rise in troponin (or fall after an elevated value) plus one or more of </li></ul><ul><ul><li>Ischemic signs or symptoms (e.g., SOB) </li></ul></ul><ul><ul><li>New pathologic Q waves on ECG </li></ul></ul><ul><ul><li>Coronary artery intervention </li></ul></ul><ul><ul><li>New wall motion abnormality or fixed defect on echo or myocardial perfusion imaging </li></ul></ul><ul><li>2) new pathologic Q waves on ECG in patients without troponin measurements </li></ul>
  7. 7. <ul><li>Study: 108 patients (96 vascular and 12 spinal procedures) </li></ul><ul><ul><li>Blood samples q6h for 36h post-surgery </li></ul></ul><ul><ul><li>Daily ECG </li></ul></ul><ul><ul><li>Baseline and day 3 echocardiogram </li></ul></ul><ul><li>Of 8 patients with new wall motion abnormalities, 8 had elevated troponin I; 6 had elevated CK-MB. False positives included 1 with elevated troponin I and 19 with elevated CK-MB </li></ul>Diagnosis of perioperative MI after noncardiac surgery
  8. 8. Prognosis of perioperative MI after noncardiac surgery <ul><li>15-25% in-hospital mortality, of which perioperative MI accounts for 2/3 </li></ul><ul><li>Nonfatal perioperative MI predisposes to death, ACS, or progressive angina: </li></ul><ul><ul><li>Post-op troponin I > 1.5 mcg/L: increased 6-mo mortality (OR 5.9) </li></ul></ul><ul><ul><li>Post-op troponin I > 0.6 mcg/L: increased 32-mo mortality (OR 2.15) </li></ul></ul>
  9. 9. Role of perioperative beta-blockers in mortality risk <ul><li>2006 retrospective study of 663,665 adults undergoing major noncardiac surgery. 18% received beta-blockers (14% RCRI-0, 44% RCRI-4+). </li></ul><ul><li>RCRI 0: 1.4% mortality, OR 1.36 [1.27-1.45] </li></ul><ul><li>RCRI 1: 2.2% mortality, OR 1.09 [1.01-1.19] </li></ul><ul><li>RCRI 2: 3.9% mortality, OR 0.88 [0.80-0.98] </li></ul><ul><li>RCRI 3: 5.8% mortality, OR 0.71 [0.63-0.80] </li></ul><ul><li>RCRI 4+: 7.4% mortality, OR 0.58 [0.50-0.67] </li></ul>
  10. 10. Choice of beta-blocker agent for perioperative administration <ul><li>Cardiovascular benefit of perioperative beta-blockers has only been demonstrated for beta-adrenergic receptor 1-selective antagonists, such as atenolol or metoprolol. </li></ul><ul><li>Retrospective cohort analysis (Redelmeier BMJ 2005) of treatment with atenolol vs. metoprolol in elderly indicated a decreased rate of death or MI after treatment with atenolol relative to metoprolol (2.5% vs 3.2% mortality). </li></ul><ul><li>Although nonselective agents such as propanolol are not initiated for perioperative therapy due to adverse pulmonary and peripheral arterial effects, patients on long-term propanolol use do not need to switch agent perioperatively. </li></ul>
  11. 11. Timing of beta-blocker administration <ul><li>Auerbach JAMA 2002 meta-analysis of timing of administration (from 1 mo prior to while in the PACU): </li></ul><ul><li>beta-blocker therapy should begin before surgery and should be continued at least through hospitalization. </li></ul><ul><li>Rapid cessation should be avoided. </li></ul>
  12. 12. Adverse effects of perioperative beta-blocker administration <ul><li>Bradycardia requiring atropine treatment is reported in >20% patients receiving perioperative beta-blockers. </li></ul><ul><li>Withdrawal may lead to adrenergic hypersensitivity, associated with accelerated angina, MI, or cardiovascular mortality. </li></ul><ul><li>Beta-adrenergic receptor 1 antagonist agents are generally safe and can be tolerated by patients with severe COPD or or reactive airway disease. </li></ul>
  13. 13. Recommendations for perioperative beta-blocker therapy <ul><li>For RCRI>2, Beta-1 selective agent, begin as an outpatient up to 30 d prior to operation, titrating to HR 50-60 BPM. </li></ul><ul><li>Longer-acting agent (atenolol or bisoprolol) may be more effective than shorter-acting agent (metoprolol). </li></ul><ul><li>No data for duration of therapy—suggest continuing for 1 month after surgery. </li></ul>