Chest Pain: To Cath or Not? Part I Georgios Papaioannou, MD Ioannis Karavas, MD Newton-Wellesley Hospital 5/3/2000 1
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. 2
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... 3
The second visit is not always easier... I wish I knew the anatomy!!! What is wrong with me? Can you fix it? Will I live forever? 4
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!!! 5
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. 6
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. 7
Risks of cardiac catheterization Unfortunately 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% 8
Major Predictors of Major Complications: Operator s skills Moribund condition. Shock. Acute MI < 24 hrs. Renal insufficiency. Cardiomyopathy. Aortic Valve disease. Mitral valve disease. CHF. 9
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!!! 10
Type of acute reperfusion in different types of hospitals JACC 2000;35:371-9) 11
In-Hospital procedures in ACS CABG<24 hs* 2 9 *P<0.05 CABG* 14 22 PTCA<6 hs* PTCA* 5 22 45 60 Invasive Hospitals Conservative Hospitals Cath<6 hs* 10 58 Cath* 51 85 JACC 2000;35:895-902. 0 20 40 60 80 100 12
Use of Angiography within 90 days of Index Hospitalization for AMI (No cumulative mortality difference!) New York (30%) Texas (45%) 100 80 P<0.001 P<0.001 P<0.001 P= 0.83 60 40 20 0 Q/NP NQ/NP Q/P NQ/P NEJM 1995;333:573-8. 13
Characteristics of Hospitals in the USA and Ontario, Canada (No survival benefit in 1 year...) 100 90 80 70 60 50 40 30 20 10 0 91.7 USA CANADA 55.4 34.9 20 24.6 21.8 5.2 3.1 6.7 2.8 None Cath Lab PTCA+CABG Angiography Revascularization NEJM 1997;336:1500-5. 14
OASIS Registry: Median in-hospital stays in days: Only in refractory angina (USA/Brazil) 14 14 12 10 8 6 4 2 5 5 7 8 10 USA Australia Brazil Canada Hungary 0 USA Australia Brazil Canada Hungary Polland Am J Cardiology 1999;84:7M-12M. 15
Status of Cardiac symptoms at One year after MI P<0.001 45 40 35 30 25 20 15 10 5 0 21 P<0.001 34 Any Chest Pain P<0.001 3 9 29 45 P=0.60 14 16 Angina Any Dyspnea Severe Dyspnea USA CANADA GUSTO Substudy, NEJM 1994;331:1130-5. 16
Cost - Effectiveness Little 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. 17
Estimated medical care Costs: ACIP Study Am J Cardiology 1999;84:1311-1316. 18
Cumulative costs in stable CAD: ACIP Study Am J Cardiology 1999:84:1311-1316.
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... 20
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. 21
Stable Angina Noninvasive 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. 22
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). 23
CABG vs Medical Therapy Duke University Study, Am J Cardiology 1997;80(9A):2I-10I. 24
CABG vs Medical Treatment: CASS Study: 10 year survival in single vessel disease Circulation 1990;82:1629-1646. 25
PTCA vs Medical Management Duke University Study, Am J Cardiology 1997:80:(9A):2I-10I. 26
Months 6 5 4 3 2 1 0 9 25 24 PTCA vs Medical treatment in 37 36 46 45 52 stable single vessel CAD 60 60 56 54 64 P<0.01 0 50 100 Medical therapy PTCA Patients without angina ACME Study, Circulation 1995;92:1710-9. 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. 27
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. 28
Acute Coronary Syndromes (ACS) Unstable Angina Non STE MI STE MI 29
High risk Predictors (Death or Nonfatal MI) >20 min Chest pain or angina at rest. Dynamic ST changes. Previous PCI or GABG. Worsening MR, S 3 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. 30
Low risk patients The 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. 31
Intermediate or High risk patients The 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. 32
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. 33
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. 34
One Year Results in TIMI IIIB (Unstable Angina) 20 18 16 14 12 10 8 6 4 2 0 3.6 3.6 8.6 9.1 10.7 11.5 Death* MI* Death or MI* 1.9 Stroke* 1.0 Early Invasive Early Conservative *P=NS JACC 1995;26:1643-1650. 35
TIMI IIIB: Repeat Hospital Admission, Anginal Status, Antiaginal Medications Early Invasive Early Conservative 100 90 80 70 60 50 40 30 20 10 0 P<0.001 8 14 P<0.005 26 33 36 36 *P=NS Readmission 6 wk Readmission 1yr Antianginal Meds 1yr* 71 69 No Angina* JACC 1995;26:1643-1650. 36
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. 37
FRISC - II Trial in ACS (6 months data) 20 18 16 14 12 10 8 6 4 2 0 P=0.10 1.9 2.9 *P=0.045 7.8 10.1 **P=0.031 9.4 12.1 Death MI* Death and MI** Early Invasive Conservative Lancet 1999;354:708-715. 38
TIMI IIIB - VANQWISH - FRISC II Differences in Revascularization rates 100 90 80 70 60 50 40 30 20 10 0 64 44 77 58 33 37 26 0 0 0 0 TIMI IIIB VANQWISH FRISC II 10 Invasive Group Conservative Group Stents GIIbIIIa 39
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. 40
The struggle for evidence... Socrates (469-399 BC) Aristotle (384-322 BC) Plato (428-347 BC) 41
The persistence in evidence... G. Galilei (1564-1642 AC) N. Copernicus (1473-1543 AC) 42
The journey to evidence... When you sail for Ithaca wish that your trip be long, full of adventures, full of knowledge... K. P. Kavafis (1863-1933) Odysseus and Penelope. 43