Chest Pain: To Cath or Not ? Part I

1

Chest Pain: To Cath or Not ?Part I

• Georgios Papaioannou, MD• Ioannis Karavas, MD

Newton-Wellesley Hospital 5/3/2000

2

A Typical Scenario...

• 57 year old female, Mrs. X., presents to your office with a 2 months history of exertional chest pressure, however she does admit that she also has the same feeling occasionally, although less severe, at rest. Symptoms resolve in 5 min most of the times without any intervention.

• She only has a history of HTN, her recent LDL is 130 and no other risk factors, no previous history of CAD.

• She is on Lisinopril and HRT.• In your office her BP is 140/90, she has a normal

physical exam and a normal ECG.

3

The easy part...

• You decide to start her on Aspirin and arrange for a ETT the next day.

• ETT results: 5 min 50 sec, achieved 85% of her MPHR , patient developed chest pressure similar to her initial complaint associated with 1 mm ST in inferior leads ; she stopped the test secondary to fatigue.

• An Echocardiogram you ordered is normal...

4

The second visit is not always easier...

• What is wrong with me ?

• Can you fix it ?

• Will I live forever ?

I wish I knew the anatomy!!!

5

Anatomy-driven or Ischemia driven decision ?

• Cardiology Consultation.• Your patient is scheduled to have a ETT with

Thallium.• Metoprolol is added to the regimen. ( No ! The

dose is not complex...)

“Ischemia-guided” or “selective invasive approach”...

It will take me a while to know the anatomy!!!

6

ACC/AHA Coronary Angiography Guidelines

• Initially published in 1987.• Intend to assist physicians in clinical decision

making.• Define practices that meet the needs of most

patients in most circumstances.• Last updated 5/1999.• Closely linked to recent demands of Evidence -

based Medicine.

7

Classification Level of Evidence

• I: General agreement about usefulness/ efficacy.

• II: Conflicting evidence - Divergence of opinion. IIa: Evidence / Opinion is in favor. IIb: Less well established.

• III: Not useful / effective, may be harmful.

• A: Multiple randomized Clinical trials.

• B: Single randomized or non randomized trials.

• C: Expert Consensus.

8

Risks of cardiac catheterizationUnfortunately there are risks...

• Mortality 0.11%

• Myocardial Infarction 0.05%

• Cerebrovascular accident 0.07%

• Arrhythmia 0.38%

• Vascular complications 0.43%

• Contrast reaction 0.37%

• Hemodynamic complications 0.26%

• Perforation of heart chamber 0.03%

• Other 0.28%

• TOTAL 1.70%

9

Major Predictors of Major Complications:

• Moribund condition.• Shock.• Acute MI < 24 hrs.• Renal insufficiency.• Cardiomyopathy.• Aortic Valve disease.• Mitral valve disease.• CHF.

Operator’s skills

10

Utilization...• 1993: 1,078,000 catheterizations annually.• 48% in people > 65 years old.• Men more likely than women.

• Whites more likely than blacks (114/100000 ).

• Medicare: 38% from 1991-1995.• Given current trends and a prediction of 40%

population growth, by 2010 3 million catheterizations in the USA annually!!!

If you also consider that Greece follows the USA trends with a 10-15 years interval ... I will most likely have a good professional life!!!

11

Type of acute reperfusion in different types of hospitals

JACC 2000;35:371-9)

12

In-Hospital procedures in ACS

51

10

22

5

14

2

85

58

60

45

22

9

0 20 40 60 80 100

Cath*

Cath<6 hs*

PTCA*

PTCA<6 hs*

CABG*

CABG<24 hs*

Invasive HospitalsConservative Hospitals

JACC 2000;35:895-902.

*P<0.05

13

Use of Angiography within 90 days of Index Hospitalization for AMI

(No cumulative mortality difference!)

0

20

40

60

80

100

Q/NP NQ/NP Q/P NQ/P

New York (30%)Texas (45%)

NEJM 1995;333:573-8.

P<0.001P<0.001

P<0.001 P= 0.83

14

Characteristics of Hospitals in the USA and Ontario, Canada

(No survival benefit in 1 year...)

55.4

2024.6

34.9

21.8

91.7

5.2 3.1 6.7 2.80

10

20304050

607080

90100

None Cath Lab PTCA+CABG Angiography Revascularization

USA

CANADA

NEJM 1997;336:1500-5.

15

OASIS Registry: Median in-hospital stays in days: Only in refractory angina (USA/Brazil)

0

2

4

6

8

10

12

14

USA Australia Brazil Canada Hungary Polland

USAAustraliaBrazilCanadaHungaryPolland

5 57

810

14

Am J Cardiology 1999;84:7M-12M.

16

Status of Cardiac symptoms at One year after MI

0

510

15

2025

30

3540

45

Any ChestPain

Angina Any Dyspnea SevereDyspnea

USACANADA

GUSTO Substudy, NEJM 1994;331:1130-5.

P<0.001

P<0.001

P<0.001

P=0.6034

21

9

3

29

45

14 16

17

Cost - EffectivenessLittle studies...

• Angiography is frequently coupled with a revascularization procedure.

• Stress PET shows the lowest cost per effect or per cost/QALY in patients with PCAD < 0.70.

• At a pretest probability > 70% (middle aged man with typical angina) proceeding to angiography as the first test has the lower cost...

Circulation 1995;91:54-65.

18

Estimated medical care Costs: ACIP Study

Am J Cardiology 1999;84:1311-1316.

Cumulative costs in stable CAD: ACIP Study

Am J Cardiology 1999:84:1311-1316.

20

Who needs an angiogram?

• ? A stable patient that has been unstable recently...

• ? An unstable patient that has been stabilized medically...

• It also matters who makes the decision...

21

Recommendations for angiography in the setting of known or suspected CAD

• High risk criteria on noninvasive testing regardless of anginal severity.

• CCS class III or IV angina on medical treatment.

• Cardiac arrest survivors, Sustained monomorphic or nonsustained polymorphic ventricular tachycardia.

Class I recommendation, ACC/AHA Guidelines 1999;33:1768.

22

Stable AnginaNoninvasive test results predicting high risk

• Severe resting LVEF (< 35%).• High risk treadmill score (score < –11).• Severe exercise left ventricular dysfunction (<35%).• Stress induced large perfusion defect (particularly anterior).• Stress induced multiple moderate perfusion defects.• Large, fixed defect with LV dilatation or lung uptake.• Echocardiographic wall motion abnormality at low dose of

dobutamine (<10 mg/kg/min) or low heart rate (<120 bpm).• Stress Echo evidence of extensive ischemia.

NEJM 1991;325:1435-9.

23

Risk Stratification

• There are no randomized trials to compare treatment strategies based only on noninvasive data.

• But there are available trials which use angiographic data to stratify patients with stable angina: High risk (Left main, 3-vessel disease, proximal LAD,

EF). Moderate risk (Multivessel CAD, normal EF). Low risk (Single vessel CAD, normal EF).

24

CABG vs Medical Therapy

Duke University Study, Am J Cardiology 1997;80(9A):2I-10I.

25

CABG vs Medical Treatment: CASS Study:10 year survival in single vessel disease

Circulation 1990;82:1629-1646.

26

PTCA vs Medical Management

Duke University Study, Am J Cardiology 1997:80:(9A):2I-10I.

27

PTCA vs Medical treatment in stable single vessel CAD

9

52

54

56

60

60

64

9

24

25

36

37

45

46

0 50 100

0

1

2

3

4

5

6

Medical therapy

PTCA

• No trial demonstrated a survival benefit of PTCA.

• Almost all trials showed improved quality of life with PTCA.

• The prognosis of single vessel disease and mild symptoms is excellent.

P<0.01

ACME Study, Circulation 1995;92:1710-9.

Months

Patients without angina

28

Also consider Coronary Angiography:Class IIa / Level of Evidence C

• CCS class III or IV which improves to I or II with medical therapy.

• Class I or II that fails to respond to therapy.

• Serial “identical” noninvasive testing showing progressively worsening abnormalities.

• A “need to know” situation in high risk professionals.

ACC/AHA Guidelines, JACC 1999;33:1770.

29

Acute Coronary Syndromes (ACS)

• Unstable Angina

• Non STE MI

• STE MI

30

High risk Predictors(Death or Nonfatal MI)

• >20 min Chest pain or angina at rest.

• Dynamic ST changes. • Previous PCI or GABG.

• Worsening MR, S3 gallop.

• Hemodynamic instability.• Pulmonary edema related

to ischemia or EF<40%.

• Elevated Serum cardiac markers:* Troponin I & T

* CPK-MB.

* Myoglobin.

• High risk criteria on noninvasive testing.

ACC SS 3/2000 : Controversies in Interventional Cardiology.

31

Low risk patientsThe goal is to determine whether revascularization is indicated.

• Class IIb recommendation:Low short-term-risk unstable angina, without high criteria on noninvasive testing (Level of evidence C)

• Intensive medical therapy and noninvasive evaluation including echocardiography for risk stratification is the way to go...

JACC 1999;33:1756-1824.

32

Intermediate or High risk patientsThe goal is whether revascularization is emergent,

urgent or ... at least beneficial!!!

• Intensive Medical management.* Aspirin.* Standard or low molecular weight heparin.* Glycoprotein IIb/IIIa inhibitors.

• Patients who do not respond after (one hour) of aggressive therapy or have recurrence after initial stabilization emergent or urgent angiography should be performed - Class I recommendation.

ACC/AHA Coronary Angiography Guidelines JACC 1999;33:1773.

33

What happens if a high risk patient stabilizes after initial treatment ?

• AHCPR proposes an “early invasive” or “early conservative” strategy...

• ACC recommends coronary angiography in high or intermediate risk patients that stabilize after initial treatment - Class I (Level of evidence A).

• ACC also recommends angiography in “initially low short-term-risk unstable angina that is subsequently high on non invasive testing” - Class I (Level of evidence B).

JACC 1999;33:1756-1824.

34

ACS: Timing of Intervention

• TIMI IIIB• VANQWISH• MATE

• DANAMI• OASIS REGISTRY• FRISC-II• MITI REGISTRY

ACS: No difference.

NQWMI: Invasive worse.

ACS: Medicine vs Angioplasty-No difference in long term.

Post MI: Invasive better (CEP).

ACS: No difference.

ACS: Invasive 22% better.

NQWMI: Invasive better.

35

One Year Results in TIMI IIIB(Unstable Angina)

02468

101214161820

Death* MI* Death orMI*

Stroke*

Early InvasiveEarly Conservative

JACC 1995;26:1643-1650.

*P=NS

3.6 3.6

8.6 9.1

10.7 11.5

1.91.0

36

TIMI IIIB: Repeat Hospital Admission, Anginal Status, Antiaginal Medications

8

2636

71

14

33 36

69

0102030405060708090

100

Readmission 6 wk Readmission 1yr Antianginal Meds1yr*

No Angina*

Early Invasive Early Conservative

JACC 1995;26:1643-1650.

P<0.001

P<0.005

*P=NS

37

FRISC - II Study• Intermediate and High risk patients.

• Dalteparin vs Placebo.

• “Early” Invasive vs Conservative.

• Dalteparin instead of standard Heparin.

• Even the Invasive Group received 4 days of Dalteparin.

• Stents at 61/70% in PCI.

• Abciximab in 10/10% in PCI.

Lancet 1999;354:708-715.

38

FRISC - II Trial in ACS(6 months data)

1.9

7.89.4

2.9

10.112.1

02468

101214161820

Death MI* Death andMI**

Early InvasiveConservative

Lancet 1999;354:708-715.

*P=0.045

**P=0.031

P=0.10

39

TIMI IIIB - VANQWISH - FRISC IIDifferences in Revascularization rates

6458

0 0

44

33

0 0

77

37

26

10

0102030405060708090

100

Invasive Group ConservativeGroup

Stents GIIbIIIa

TIMI IIIB

VANQWISH

FRISC II

40

Summary: After the trials...

• Pathophysiology of unstable angina is clear.

• Management of ACS is still controversial.

• High risk patients seem to benefit from “early” invasive approach.

• Use of LMWH, GIIbIIIa inhibitors, Statins.

• Use of stents in combination with potent antiplatelet therapy.

41

The struggle for evidence...

Socrates (469-399 BC)

Aristotle (384-322 BC)Plato (428-347 BC)

42

The persistence in evidence...

G. Galilei (1564-1642 AC) N. Copernicus (1473-1543 AC)

43

The journey to evidence...

Odysseus and Penelope.

“When you sail for Ithaca

wish that your trip be long,

full of adventures,

full of knowledge...”

K. P. Kavafis (1863-1933)