Delaying Surgery After Acute MI A 63-year-old man suffers an acute - PDF document

Updates and Controversies in Perioperative Medicine How long should we delay surgery after: Updates and Controversies in • Acute myocardial infarction? Perioperative Medicine • Drug-eluting stent implantation? • Ischemic stroke? Which patients need bridging anticoagulaion? Hugo Quinny Cheng, MD Postoperative anemia: Division of Hospital Medicine • How much evaluation is needed? University of California, San Francisco • When should patients be transfused? Delaying Surgery After MI Delaying Surgery After Acute MI A 63-year-old man suffers an acute myocardial infarction, Question: How does time between acute MI and treated without PCI. He was already scheduled for prostate surgery affect the risk of postoperative MI? cancer surgery in one month. Because of his recent MI, you recommend delaying surgery for: 563,842 patients (1999-2004) discharged after hip surgery, colectomy, cholecystectomy, AAA repair, or A. 1 month lower extremity amputation: B. 2 months • 2.9% of cohort had experienced acute MI in prior year C. 3 months • Outcome: 30-day postoperative MI D. 6 months E. At least a year Livhits M et al. Annals of Surgery 2011; 253:857-63 1

How Long to Wait after MI? Delaying Surgery after Acute MI Conclusions: 35% • Surgery within one year of acute MI associated with high 30% 30-Day Postop MI risk of postoperative MI 25% 20% • Risk falls over time; most of the reduction within 2 months 15% • Trend is similar when only elective surgery considered 10% Caveats: 5% • Nonrandomized, observational study 0% ACC/AHA Guidelines: < 30 31-60 61-90 91-180 181-365 • Delay elective surgery for at least 2 months after MI Time (days) Between Acute MI & Surgery Surgery After Drug Eluting Stent Effect of Stent Type & Time After Implantation A 75-y.o. man sustains an unstable cervical spine fracture. He had a drug-eluting stent placed 3 Time of surgery after PCI didn’t matter after first 6 months months ago for stable angina. The spine surgeon 20% wants to operate, but putting him in a halo vest is 6 months Bare Metal Complications a less desirable alternative approach. 15% Drug Eluting What do you recommend? 10% 1. Operate now; 3 months is fine 5% 2. Wait 6 months after DES placed 60 120 180 240 300 360 3. Wait 12 months after DES placed Time between PCI & Surgery Hawn MT et al. JAMA . doi:10.1001/jama.2013.278787 2

Delaying Surgery After Stroke ACC/AHA Guidelines for PCI A 63-year-old man suffers an acute stroke that is managed without thrombolysis. Brain MRI incidentally detects a large • Indications for PCI are same as for nonsurgical patients meningioma. The neurosurgeon wants to resect the tumor in • Avoid PCI if antiplatelet drugs will need to be held prematurely 2 weeks. Because of his stroke, you recommend delaying surgery for: • Delay elective surgery after elective PCI at least: Bare metal stent: 30 days A. 1 month Drug eluting stent: 6 months (optimal) B. 3 months 3 months (if harm in delay) • Continue or restart antiplatelet agents (especially ASA) as C. 6 months soon as hemostasis permits D. 9 months E. At least a year Delaying Surgery After Stroke Delaying Surgery After Stroke 20% Question: How does time between stroke and surgery affect the risk of cardiovascular complications? MACE Incidence CV Death 15% Ischemic Stroke Danish cohort study of all adults undergoing elective Acute MI 10% noncardiac surgery from 2005-2011: • 7137 patients had prior stroke (1.5% of total cohort) 5% • Outcome: 30-d postop Major Adverse Cardiac Events (MACE): cardiovascular death, nonfatal MI, ischemic stroke • Looked at effect of time since stroke on MACE rate 0% < 3 months 3-6 months 6-12 months > 12 months Time Between Acute Stroke & Surgery Jorgenson ME et al. JAMA 2014; 312:269-277 3

Managing Perioperative Anticoagulation How Long to Wait after CVA? Two patients on warfarin therapy are scheduled for elective hip arthroplasty. You’re asked whether they should receive Conclusions: perioperative bridging anticoagulation (with enoxaparin): • Surgery after CVA associated with high CV risk One patient has atrial fibrillation due to hypertension • • Risk falls over 9 months, biggest drop after first 3 months • The other patient has a St. Jude mechanical AVR Caveats: • Neither has any other relevant comorbidity • Nonrandomized, observational study 1. Bridge for AVR only My take-away: 2. Bridge for AF only • Delay elective surgery for at least 3 months (up to 9 3. Bridge for both months) if possible 4. Bridge for neither Benefits & Harm of Bridging BRIDGE Trial Perioperative Anticoagulation Patients: • 1884 patients on warfarin for atrial fib or flutter • CHADS-2 score > 1 Benefit from Harm from • Excluded patients with mechanical valve or stroke within thromboembolism postoperative bleeding 12 weeks and cardiac & neurologic surgery averted by bridging caused by bridging Intervention: • Randomized to bridging with LMWH or placebo Outcome: • 30-day risk of arterial thromboembolism & bleeding Douketis JD et al. NEJM, 2015; 373:823-33 4

BRIDGE Trial BRIDGE Trial for Atrial Fibrillation Conclusions: Bridged No Bridge • Bridging did not reduce risk of embolism • Bridging increases bleeding risk Non-inferior Embolic Event 0.3% 0.4% Caveats: • Few patients with high CHADS-2 score (mean = 2.3) Major Bleeding 3.2% 1.3% NNH = 53 My take-away: • Don’t bridge majority of atrial fibrillation Minor Bleeding 21% 12% NNH = 12 • Carefully consider bridging if stroke risk is very high (CHADS-2 score 5 or 6, rheumatic atrial fibrillation) Douketis JD et al. NEJM, 2015; 373:823-33 Effect of Mechanical Valve Location & What About Mechanical Valves? Design on Thromboembolic Risk Valve Location: 7% Thromboembolic 6% Aortic RR = 1.0 Atrial Fibrillation Risk (annual) 5% Mitral RR = 1.8 Mechanical Valve 4% Valve Design: 3% 2% Caged Ball RR = 1.0 1% Tilting Disk RR = 0.7 0% Bi-leaflet RR = 0.6 Without Anticoagulation With Warfarin Ansell J. Chest. 2004;126:204S-233S. Cannegieter, et al. Circulation , 1994 Cannegieter, et al. Circulation , 1994 5

Perioperative Anticoagulation: Perioperative Anticoagulation: 2012 ACCP Guidelines (9 th Edition) My Approach after BRIDGE Trial Atrial Fib. Mechanical Valve Recommendation Atrial Fib. Mechanical Valve Recommendation CHADS 2 = 5-6; Any MVR; older (caged- Bridge with heparin CHADS 2 = 5-6; Any MVR; older (caged- Consider recent CVA; ball or tilting disc) AVR; recent CVA; ball or tilting disc) AVR; bridging rheumatic AF recent CVA rheumatic AF recent CVA CHADS 2 = 3-4 Bileaflet AVR plus other ??? CHADS 2 = 3-4 Bileaflet AVR plus other stroke risk factor(s) stroke risk factor(s) No bridge CHADS 2 = 0-2 Bileaflet AVR without AF or No heparin bridge CHADS 2 = 0-2 Bileaflet AVR without AF or other stroke risk factor other stroke risk factor What About Venous Clots? What About Venous Clots? Retrospective cohort study Risk of Recurrent VTE • 1178 patients on warfarin for DVT or PE • Outcome: 30-day recurrent clotting & significant bleeding Bridged No Bridge Hazard Ratio Recurrent VTE 0% 0.2% ns Bleeding 2.7% 0.2% 17 (4-75) Time Since Venous Thromboembolic Event Clark NP et al. JAMA Int Med , 2015; 175:1163 6

How About Venous Clots? Venous Clots: 2012 ACCP Guideline Conclusions: Risk of Recurrent VTE Recommendation • Recurrent VTE is rare & bridging didn’t affect risk High Risk: Bridge • Bridging increases bleeding VTE < 3 months ago; Caveats: Severe thrombophilia • Nonrandomized study, so selection bias Medium Risk: Case-by-case • Few patients were considered high-risk for recurrence VTE 3-12 months ago; recurrent VTE; decision VTE with cancer other thrombophilia My practice: Low: No bridge • Bridge or place temporary IVC filter only in high-risk group Single VTE > 12 months ago Clark NP et al. JAMA Int Med , 2015; 175:1163 Venous Clots: My Approach Postoperative Anemia You visit a 79-year-old woman on postoperative day #1 after Risk of Recurrent VTE Recommendation hip fracture repair. You notice her hemoglobin dropped from High Risk: Consider bridging 11.6 g/dL before surgery to 8.5 g/dL today. The operative note reports an EBL (estimated blood loss) of 300 mL. VTE < 3 months ago; or IVC filter Severe thrombophilia Which of the following actions is most likely to be useful? Medium Risk: 1. Labs to rule out coagulopathy VTE 3-12 months ago; recurrent VTE; 2. Labs to rule out hemolysis No bridge VTE with cancer other thrombophilia 3. CT to rule out retroperitoneal Low: hematoma Single VTE > 12 months ago 4. No work-up; the EBL is wrong 7