British Cardiac Intervention SocietyBritish Cardiac Intervention Society

Risk AssessmentRisk AssessmentInIn

Acute Coronary SyndromesAcute Coronary Syndromes

Dr David NewbyDr David Newby

BHF Senior Lecturer in CardiologyBHF Senior Lecturer in CardiologyAssociate Director of Wellcome Trust Clinical Research FacilityAssociate Director of Wellcome Trust Clinical Research Facility

Case 1

• 46 year old woman

• Family history of ischaemic heart disease, hypertension, smoker and hypercholesterolaemia

• No prior history of angina

• 3 episodes of chest pain 12 hours prior to admission

• Already taking aspirin and statin on admission

• ECG normal

• Troponin I 1.2 µg/L

Case 1

Commenced on medical therapy and settles

Would you manage the patient with:

(a). In-patient coronary angiography and revascularise

(b). Conservative treatment and consider angiography/revascularisation if symptoms recur

Case 2

• 79 year old man

• Non-smoker, hypertension and no risk factors

• Chronic stable angina for 15 years with known single vessel disease (angiogram 10 years ago)

• One episode of rest pain prior to admission

• Not taking aspirin

• ECG - minor ST depression on admission

• Troponin I <0.1 µg/L

Case 2

Commenced on medical therapy and settles

Would you manage the patient with:

(a). In-patient coronary angiography and revascularise

(b). Conservative treatment and consider angiography/revascularisation if symptoms recur

TIMI Risk Score

• Age ≥ 65 years

• ≥3 Risk factors for coronary artery disease

• Significant coronary stenosis

• ST Segment deviation

• Severe anginal symptoms (≥2 anginal events in last 24 hours)

• Prior aspirin use (within last 7 days)

• Elevated serum cardiac markers

Antman et al. JAMA 2000;284:835-842

Antman et al. JAMA 2000;284:835-842

Antman et al. JAMA 2000;284:835-842

TIMI Risk Score and Benefit with LMW Heparin

Case 1 Case 2

Age ≥65 0 1≥3 Risk factors for CAD 1 0Significant CAD 0 1ST Segment deviation 0 1Angina ≥2 times within 24 hrs 1 0Prior aspirin use 1 0Elevated cardiac markers 1 0

Total TIMI Score 4 3

14 Day Event Rate 20% 13%

TIMI Risk Score

Other Risk Factors and Scores

• Robust data on in-hospital & 6-month outcomes in over 12,000 patients in 14 different countries

• In well-characterized patients with ACS:– In-hospital to 6 month rates of:– death: ST-MI 12%, Non-ST-MI 13%, UA 8%– Stroke: 1.5 to 3%– Recurrent hospitalization for cardiac event: 17 to 20%

• Unselected patients reveal substantially higher event rates than those entered into recent trials

• A major challenge exists in the application of proven therapies to the full spectrum of patients with ACS

GRACE Registry

SBP (per 20 mmHg increase) 0.7 0.69-0.78

Initial serum creatinine 1.2 1.15-1.35

Heart rate 30bpm 1.3 1.16-1.48

Initial cardiac enzyme + 1.6 1.32-2.00

Age (per 10 yr) 1.7 1.55-1.85

Killip class 2.0 1.81-2.29

ST deviation 2.4 1.90-3.00

Pre-hosp arrest 4.3 2.80-6.72

-2 –1 0 1 2 3 4 5 6 7 8

Multivariable Risk Model

Comparison of TIMI Risk Scores for Death: Antman Data Vs. GRACE Data

0

1

2

3

4

5

6

7

0/1 2 3 4 5 '6/7

TIMI Risk Score

AntmanGRACE

DeathRate(%)

Outcome of “low-risk” patients with ACS

Presentation with UA in the absence of dynamic ECG changes, no troponin elevation, no arrhythmia nor

hypotension

6 month outcome:– 16.6% readmission– 8.7% revascularised– 2.2% deaths– 0.2% MI

“Low-risk” is not no risk

FRISC II Study

Wallentin et al. Lancet 2000;356:9-16.

RITA-3 Study

Fox et al. Lancet 2002;360:743-751

Fox et al. Lancet 2002;360:743-751

Meta-analysis of Intervention Trials

Who Should We Target ForInvasive Intervention?

•MEN

•≥65 YEARS

•CHRONIC ANGINA

•NON-SMOKERS

•CHEST PAIN at REST

•(TROPONIN +VE)

•ST DEPRESSION

FRISC II et al. Lancet 1999;354:708-715

Case 1 Case 2

Age 1.00 0.66Sex 1.26 0.64Smoking 1.34 0.66Angina > 3 months 0.95 0.59ST Segment deviation 0.94 0.66Elevated cardiac markers 0.73 0.80

14 Day TIMI Event Rate 20% 13%

Benefit from Intervention No Yes

6 Month Risk Reduction Based on FRISC Dataset

Risk AssessmentIn

Acute Coronary Syndromes

Evaluation of Treatment BenefitIn

Acute Coronary Syndromes

Single Vessel Disease

Two Vessel Disease

Three Vessel Disease

75% Left Main Stem

95% Left Main Stem

0.0 0.5 1.0 1.5 2.0 2.5

Harzard Ratio

Survival Benefits of Revascularisation

25

20

15

10

5

0

0 5-49 50-85 >85

Severity of Luminal Stenosis (%)

Frequency (%) of 5 yearVessel Occlusion or

Myocardial Infarction

<50%

50-70%

>70%

68%

18%

14%

Severity of Underlying Luminal Stenosis

in Patients with anAcute Myocardial Infarction

LuminalStenosis

Frequency

Degree of Stenosis in the Culprit Lesionof Acute Myocardial Infarction

Conclusions

• Risk scores need to be carefully applied

• Risk scores may be population dependent and not reflect ‘true life’ populations

• Low risk is not no risk

• High risk does not equate to most benefit from intervention

• Is the benefit of interventional strategies for acute coronary syndromes derived from revascularising patients with prior stable angina and prognostically significant disease?