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

Management of Acute Myocardial Infarction

Minimal Acceptable vs Optimal Care

Hussien H. Rizk, MDCairo University

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

Clinical proceedings of a suspected MI

• 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?

Should everybody with acute MI have:

• Statin?• Clopedogrel?

• Platelet GP II b/III a inhibitor?

• Primary PCI?

Timing of Statin Therapy Initiation After ACS in Recent Clinical Studies

Days

Secondary prevention

0 6Months

32

L-CAD CARE

LIPID

24Hours

10 6 8 1212 18 4

MIRACL

4S

6

Atorvastatin

Pravastatin

Simvastatin

PROVE IT

WOSCOPS

Primary prevention

ACS

Fluvastatin

FLORIDA

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

Time Since Randomisation (Weeks)

0 4 8 12 16

15

10

5

0

Placebo 17.4%

Atorvastatin 14.8%

Risk reduction = 16%P=0.048

95% CI = 0.701–0.999

Time to first occurrence of composite endpoint of: Death (any cause) Non-fatal MI Resuscitated cardiac arrest Worsening angina with new

objective evidence and urgent rehospitalisation

Schwartz GG et al. JAMA 2001;255:1711-8.

MIRACL: Primary Efficacy Measure

Cumulative Incidence

(%)

Placebo 8.4%

Atorvastatin 6.2%

MIRACL Worsening Angina with New Objective Evidence

of Ischemia Requiring Urgent Hospitalisation

Risk reduction = 26%P=0.02

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

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.

Tirofiban in ACS: 1.5% ARR of 30D mortality compared to heparin alone

PRISM. NEJM 1998;338:1498 NNT = 67

Cost/event = LE 130,000

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

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

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