Management of Acute Myocardial Infarction

1. Management of Acute Myocardial Infarction Minimal Acceptable vs Optimal Care Hussien H. Rizk, MD Cairo University

2. Background • Suspicious chest pain: extremely common cause of ER visits • Acute MI: the most costly cardiac cause of ER visits • 5-10% of acute MI patients are missed because of errors in symptom interpretation or missed ECG diagnosis • Many patients do not receive proven inexpensive effective therapy

3. Symptom evaluation Pain characteristics Heart failure, syncope Contraindication to SK Physical examination ECG Quick Interpretation correct Lab work-up Basic [Sugar. CRT. K. CK if no ST elevation] CXR Specific [Clinically guided] Disposal: Discharge Observation Admission Referral Relief of symptoms Pain Nausea Anxiety Aspirin Saves as many lives as SK ACE-I Low dose [Captopril 6.25] Not if SBP<100 BB Thrombolysis SK TPA: SK sensitive or recent use Primary PCI: Who? Where? Clinical proceedings of a suspected MI

4. Should everybody with acute MI have: • Statin? • Clopedogrel? • Platelet GP II b/III a inhibitor? • Primary PCI?

5. Timing of Statin Therapy Initiation After ACS in Recent Clinical Studies Atorvastatin Pravastatin MIRACL Simvastatin Fluvastatin PROVE IT 4S WOSCOPS FLORIDA CARE L-CAD ACS LIPID Primary prevention Secondary prevention 3 6 0 6 12 18 24 2 4 6 8 10 12 Hours Days Months

6. MIRACLStudy Outcome Measures Primary • Death, Non-fatal MI, Cardiac arrest • Worsening angina + evidence of myocardial ischemia. Secondary • Stroke • Revascularization. • Worsening CHF • Worsening angina without evidence of ischemia Schwartz GG et al. JAMA 2001;255:1711

7. MIRACLWorsening Angina with New Objective Evidence of Ischemia Requiring Urgent Hospitalisation Placebo 8.4% Placebo 17.4% Atorvastatin 14.8% Time to first occurrence of composite endpoint of: Atorvastatin 6.2% • Death (any cause) • Non-fatal MI • Resuscitated cardiac arrest • Worsening angina with new objective evidence and urgent rehospitalisation Risk reduction = 26% P=0.02 MIRACL: Primary Efficacy Measure Risk reduction = 16% P=0.048 15 CumulativeIncidence (%) 95% CI = 0.701–0.999 10 5 0 0 4 8 12 16 Time Since Randomisation (Weeks) Schwartz GG et al. JAMA 2001;255:1711-8.

8. MIRACL: COST-BENEFIT • Absolute risk reduction for worsening angina: 2.2% • NNT = 100/2.2 = 45.5 • Cost of avoiding one worsening angina event = NNT x No of Days x Daily cost (Ignoring lab tests & treating complications) = 45.5 x 120 X 36 = 196,364 LE

9. GP II b/III a inhibitors for medically treated acute coronary syndromes • GUSTO 4-ACS: Abciximab, no acute revascularization. No benefit at 30D (Simoons. Lancet 2001;357:1915) or 1Y (Ottervanger et al. CIRCULATION 2003;107:437) • GRAPE pilot: abciximab for acute MI: TIMI 3 flow in 20% (van der Merkhof et al. JACC 1999;33:1528) • PRISM: Tirofiban reduced total mortality compared to heparin alone.

10. Tirofiban in ACS: 1.5% ARR of 30D mortality compared to heparin alonePRISM. NEJM 1998;338:1498 NNT = 67 Cost/event = LE 130,000

11. PRISM PLUS: terminated prematurely for excess mortality with tirofiban (4.6% vs 1.1% for heparin alone)

13. DANAMI-2 COST-BENEFIT • 6% Absolute risk reduction • NNT = 16.7 • Procedure cost: LE 14,000 • Cost of preventing ONE EVENT (MI) at 30D = LE 233,800

14. MINIMAL ACCEPTABLE CARE FOR MI • CLINICAL TRAINING COST-EFFECTIVE • ROUTINE LAB: FBS. BUN. K. CK. CXR • ROUTINE Rx. SYMPTOMS. ASA. SK. BB. ACE-I • NOT ROUTINE: • TPA • CLOPEDOGREL • STATIN • PLATELET GLYCOPROTEIN INHIBITORS • PRIMARY PCI