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Angioplasty: A Reality Check! What Does Evidence Based Medicine Tell Us?. Duane S. Pinto, M.D. Director Peripheral Angiographic Core Laboratory, TIMI Data Coordinating Center. Director, Cardiology Fellowship Training Program Interventional Cardiologist, Beth Israel Deaconess Medical Center.

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Angioplasty a reality check what does evidence based medicine tell us
Angioplasty: A Reality Check!What Does Evidence Based Medicine Tell Us?

Duane S. Pinto, M.D.

Director Peripheral Angiographic Core Laboratory,

TIMI Data Coordinating Center

Director, Cardiology Fellowship Training Program

Interventional Cardiologist, Beth Israel Deaconess Medical Center

Assistant Professor of Medicine, Harvard Medical School


Conventional wisdom
Conventional Wisdom

  • Treatment Assumptions in CAD Management:

  • Patients with symptomatic CAD and chronic angina who have significant coronary stenoses “need” revascularization

  • Revascularization is required to improve prognosis

  • PCI is less invasive than CABG surgery (i.e., is safer) and, therefore, should be selected


Real patient
Real Patient!

To: Pinto,Duane (Cardiology) <[email protected]>Sent: Tue Jun 27 15:41:21 2006Subject: are you back?I have a patient who had a positive stress today - I think he needs a cath (though, in retrospect, perhaps I should have sent him straight for cath - but he's hard to convince)


Straight to cath
Straight to Cath?

Costs of care are increased with greater pretest risk, but are elevated by 30% to 40% for patients undergoing direct catheterization

Direct Cath

NIVT + Selective Cath

4.8

4.2

2.9

2.8

Dollars (Thousands)

Dollars (Thousands)

2.4

2.0

N=813

N=1682

N=816

N=1631

N=2928

N=3379

Economics of Noninvasive Diagnosis Multicenter Study Group. J Am Coll Cardiol. 1999; 33: 661


Stress test results
Stress Test Results

Exercised for 5 Minutes on the Bruce Protocol. Stopped for fatigue. Achieved RPP 20,000 (85% Maximum predicted HR). 0.5 mm horizontal ST depressions.


Pop quiz 1
Pop Quiz #1!

  • Based on this result, this patient’s annual risk of MI is estimated to be:

    • 0.5%

    • 2.9%

    • 7.4%

    • 9.3%

    • 12.7%


The duke treadmill score

Our Patient: 5 - 2.5 - 0= 2.5

The Duke Treadmill Score

Exercise time - (5 X ST Deviation) – (4 X Angina Index)= Score

Angina index:

  • 0 No angina

  • 1 Typical angina during exercise

  • 2 Stop exercise for angina

  • Low risk: 5 or greater

  • Medium Risk: -10 to +4

  • High risk: -11 or less

  • Cardiac Death (%)

    Mark DB. Ann Inter Med. 1987: 106; 793.

    Hachamovich R. Circulation 1996; 93: 905.


    Treadmill score prognosis and prevalence of disease

    ½ of men at low clinical risk (0.9% mortality/year) will have CAD

    Treadmill Score: Prognosis and Prevalence of Disease

    VD = Vessel Disease;  LM = Left Main

    Alexander KP, et al. J Am Coll Cardiol 1998; 32:1657-64

    Mark DB, et al. Ann Int Med 1987; 106:793-800.

    Mark DB, et al. N Engl J Med 1991; 325:849-53


    Stress test results1
    Stress Test Results have CAD

    Exercised for 5 Minutes on the Bruce Protocol. Stopped for fatigue. Achieved RPP 20,000 (85% Maximum predicted HR). 0.5 mm horizontal ST depressions.


    Perfusion imaging adds to prognosis
    Perfusion Imaging Adds to Prognosis have CAD

    Event Rate (%/yr)

    Hachamovitch R. Circulation. 1998; 97: 535.


    History
    History have CAD


    Everybody s happy
    Everybody’s Happy! have CAD

    • Patient’s Happy-”My blockage is now fixed!”

    • Referring MD Happy -”Whew! Heart attack averted!”

    • Interventional Cardiologist Happy-”Another successful (billable?) procedure!”

    • Hospital’s Happy-”I like that DRG!”

      What were the goals of care?

      Did we practice evidence based medicine?


    The truth
    The Truth have CAD

    • There is no evidence that the stent placed in this patient altered his long-term rate of death or MI

      • I am happy/lucky he did not have a periprocedural MI

      • Certainly, his risk of stent thrombosis (10% in hospital mortality) is increased compared with medical therapy now that he has a stent!

    • If dyspnea was an anginal equivalent (ischemic MR), then that may get better

      • It did at 3 month follow-up

    • Procedures don’t always go well

      • The risk for providing this symptom control was periprocedural MI, stroke, emergency CABG, bleeding, vascular injury & need for long-term anti-platelet therapy


    Ratio of rates of percutaneous coronary intervention to the u s average 1996

    1 have CAD

    .30

    to

    2

    .97

    (57)

    1

    .10

    to <

    1

    .30

    (47)

    0

    .90

    to <

    1

    .10

    (83)

    0

    .75

    to <

    0

    .90

    (51)

    0

    .35

    to <

    0

    .75

    (68)

    Not Populated

    Ratio of Rates of Percutaneous Coronary Intervention to the U.S. Average (1996)


    Pci facts
    PCI Facts have CAD

    • Rates of cardiac catheterization and coronary revascularization among Medicare acute myocardial infarction patients increased by 45% and 70% between 1987 and 1992

    • There are 1,000,000 PCI procedures in the US per year and 2,000,000 worldwide


    Assessing quality in medical care
    Assessing Quality in Medical Care have CAD

    • Current paradigm of quality improvement generally focuses on identifying of specific processes of care (e.g., guidelines) and assessing how frequently they are achieved in an “ideal patient population”

      • JCAHO, HEDIS measures, etc.

    • Much less attention has traditionally been paid to the frequency of overuse of treatments in patients for whom there is little or no evidence of benefit

    • As compliance with standard performance measures increases, however, much of the real opportunity to improve quality of care may lie in identifying inappropriate care/overuse


    Pci appropriateness by hospital
    PCI Appropriateness by Hospital have CAD

    • NY State 1990

    • Random sample of 1306 pts undergoing PCI

    • Appropriateness based on modified Delphi Method

    • Independent angiographic readings suggests another 10% may also be inappropriate as well

    Hilborne LH et al. JAMA 1993;269:761-5


    Potential impact of inappropriate pci

    Evidence-Based Medicine have CAD

    Potential Impact of Inappropriate PCI

    • Low-volume hospital

    • 900,000 PCI/yr in US

    • 15% of PCI at low-volume hospital (LVH)

    • 1.3 x mortality risk at LVH vs. HVH

    • 0.5% in-hospital mortality for elective PCI

    • Inappropriate/Uncertain PCI

    • 900,000 PCI/yr in US

    • 6% inappropriate and 38% uncertain

    • 0-25% of uncertain PCI are actually inappropriate

    • 0.5% in-hospital mortality for elective PCI

    270 - 698 deaths avoidable by eliminating inappropriate PCI

    214 avoidable deaths (by switching all LVH to HVH)


    Appropriateness of pci weighing the evidence
    Appropriateness of PCI: have CADWeighing the Evidence

    • Although more than 27 million pts have undergone PCI since 1977, only ~6,500 have been enrolled in RCTs of PCI vs. medical therapy (0.02%)

    • RCTs of PCI vs. both medical therapy and bypass surgery are limited by outdated technology and highly restricted patient populations

      • <4% of current PCI population

    • ACC/AHA guidelines leave much of current PCI practice in the “gray-zone”


    Lies damned lies and

    Lies, Damned Lies, and…. have CAD

    6 Common Misconceptions about PCI


    Pci misconception 1

    Evidence-Based Medicine have CAD

    PCI Misconception #1

    Misconception

    “Doc said I had a 90% blockage. Thank goodness he fixed it in time and saved my life”

    • Facts

    • There is no such thing as a 90% stenosis

    • Even if there were, in most cases PCI is not a life-saving intervention


    Evidence-Based Medicine have CAD

    PCI Misconception #2

    Misconception

    “Mr. Jones had severe 2-vessel disease but really didn’t want a bypass operation, so I stented both vessels”

    • Facts

    • PCI is often the first step on the road to CABG

    • If a patient really wants to avoid CABG at all costs, medical therapy is the way to go


    Pop quiz 2
    Pop Quiz #2 have CAD

    • How many patients with 3 Vessel Coronary Disease need to be sent to CABG vs. Medical Therapy to save a life at 10 years?

      A. 1 (CABG is better than medical therapy)

      B. 10

      C. 15

      D. 25


    Pop quiz 21
    Pop Quiz #2 have CAD

    • How many patients with 3 Vessel Coronary Disease need to be sent to CABG vs. Medical Therapy to save a life at 10 years?

      A. 1 (CABG is better than medical therapy)

      B. 10

      C. 15

      D. 25

    (10 yr Mortality CABG 26.4% vs. 30.5% Medical Therapy; p=0.03)


    Pci misconception 3

    Evidence-Based Medicine have CAD

    PCI Misconception #3

    Misconception

    “For most patients with multivessel disease, PCI can provide comparable long-term survival benefits and quality of life as bypass surgery”

    • Facts

    • The randomized trials of PCI vs. CABG have included only highly selected patients

    • Observational data still suggest improved survival with CABG in severe multivessel dz


    Pci misconception 4

    Evidence-Based Medicine have CAD

    PCI Misconception #4

    Misconception

    “Everyone should get primary PCI for ST-Elevation MI”

    • Facts

    • The randomized trials of PCI vs. fibrinolyis have included only highly selected patients with rapid treatment times

    • Observational data still suggest that treatment times are very prolonged in the US, particularly for transfer patients


    Times in randomized trials vs the real world
    Times in Randomized Trials vs. the “Real World” have CAD

    Median Door to Balloon Time: 180 min

    Median Door to Door (Transfer) Time: 120 Min

    Median PCI Hospital DB time: 53 Min

    <5% of patients had Total DB time <90 Min if a transfer was involved

    Compare this to the randomized studies with: Total DB times of 90 min, Transport times of 30 min, and PCI hospital DB times of 25 min

    BK Nallamothu, ER Bates, HM Krumholz, et al. Circulation 2005; 761


    Pci misconception 5

    Evidence-Based Medicine have CAD

    PCI Misconception #5

    Misconception

    An asymptomatic patient with an abnormal ETT is at high risk for short term complications

    “Thankfully, doc ordered that screening stress test when I turned 50 and that other nice doctor did an angioplasty the next day. I could have had a heart attack!”

    • Facts

    • The benefit of revascularization in asymptomatic patients (even our high-risk diabetic patients) is likely restricted to those with high risk stress test findings.

    • Risk of periprocedural MI approximates annual risk insome cases

    Sorraja P. Circulation. 2005; 112: I311


    Pci misconception 6

    Evidence-Based Medicine have CAD

    PCI Misconception #6

    Misconception

    Stable Angina means the patient needs revascularization to prevent a heart attack

    “Thankfully, doc sent me to the hospital for those chest pains and that other nice doctor did an angioplasty the next day. I could have had a heart attack!”

    • Facts

    • PCI reduces symptoms in chronic angina and may increase the risk of MI, or needing a CABG

    Sorraja P. Circulation. 2005; 112: I311


    Pci in chronic angina

    Evidence-Based Medicine have CAD

    PCI in Chronic Angina

    • 6 randomized trials (n=1904)

    • Symptomatic relief favored PCI (risk ratio=0.70)

    • All other outcomes (death, MI, CABG) tended to favor medical rx, but only CABG statistically significant

    • Unknown whether recent advances (stents, Gp2b/3a) have abolished excess ischemic complications

    PCI  Reduced Angina

    PCI  More Complications ?

    Bucher H et al. BMJ 2000;321:73-7


    Stable cad pci vs conservative medical management
    Stable CAD: PCI vs Conservative have CADMedical Management

    Meta-analysis of 11 randomized trials; N = 2,950

    Favors PCI

    Favors Medical Management

    0

    1

    2

    Risk ratio

    (95% Cl)

    Katritsis DG et al. Circulation. 2005;111:2906-12.


    Pci for chronic angina

    Evidence-Based Medicine have CAD

    PCI for Chronic Angina

    • PCI compared with medical therapy is associated with better control of angina and improved functional status but increases the chances of subsequent CABG

      • Data analyzed are prior to widespread use of DES

    • It is appropriate to treat patients without high risk noninvasive testing with anti-anginal therapy and then refer those who fail medical therapy

      • Assess the amount of myocardium at risk

        • Those with low or intermediate risk stress test predictors need not undergo angiography

        • Those with high risk stress predictors should undergo further risk stratification with angiography


    Pci in possible angina without ischemia

    FFR have CAD

    FFR  0.75

    FFR < 0.75

    Randomize

    PCI

    Med Rx

    PCI

    P=NS

    11%

    17%

    22%

    2-year death/MI/repeat revasc.

    Evidence-Based Medicine

    PCI in Possible Angina without Ischemia

    PCI ?????

    • 57% of patients scheduled for PCI had normal FFR (i.e, no ischemia)

    • No difference in f/u anginal class

    • Costs ~$2500/pt higher with PCI strategy (no change in DES era)

    Pt scheduled for PCI but without documented ischemia (n=327)

    DEFERTrial

    Bech GW et al. Circulation 2001;103:2928-34


    What is appropriate pci

    Evidence-Based Medicine have CAD

    What is “appropriate” PCI?

    • What are the proven benefits of PCI?

    • Key barriers to controlling overuse

    • Suggestions for improving appropriateness

    • Who should not receive PCI in 2007?


    Pci for stemi short term clinical outcomes

    Evidence-Based Medicine have CAD

    PCI for STEMI:Short Term Clinical Outcomes

    PCI

    Fibrinolysis

    P < 0.0001

    Frequency (%)

    P < 0.0001

    P=0.0002

    P=0.032

    P=0.0003

    P < 0.0001

    P=0.0004

    P < 0.0001

    Hem.Stroke

    Death

    Death, no SHOCKdata

    ReMI

    Rec.Ischemia

    Total Stroke

    Major Bleed

    DeathMICVA

    N = 7739

    Keeley E. et al., Lancet 2003; 361:13-20.


    Ecg and outcome in tactics timi 18

    Conservative have CAD

    Invasive

    Risk Stratification

    ECG and Outcome in TACTICS/TIMI 18

    Death / MI / Rehospitalization at 6 Months

    ST-segment s

    ( n = 852 )

    No ST-segment s

    ( n = 1368 )

    Cannon et al. N Engl J Med 2001; 344: 1879-87


    Troponin and outcome in tactics timi 18

    Risk Stratification have CAD

    Troponin and Outcome in TACTICS/TIMI 18

    30 Days

    6 Months

    <0.001

    <0.001

    Tn T > 0.01 ng/ml

    Tn T > 0.01 ng/ml

    0.082

    0.002

    Death/MI/hosp

    Death/MI

    Death/MI/hosp

    Death/MI

    Conservative

    0.46

    Tn T < 0.01 ng/ml

    Tn T < 0.01 ng/ml

    Invasive

    0.80

    0.58

    0.90

    Death/MI/hosp

    Death/MI

    Death/MI/hosp

    Death/MI

    Cannon et al. N Engl J Med 2001; 344: 1879-87


    Revascularization in asymptomatic diabetics

    Evidence-Based Medicine have CAD

    Revascularization in Asymptomatic Diabetics

    • The benefit in this study was confined to those with high-risk perfusion abnormalities

    PCI  Improved survival

    Sorraja P. Circulation. 2005; 112: I311


    Challenges to controlling overuse of pci
    Challenges to Controlling Overuse of PCI have CAD

    • Increasing safety of PCI

      • Perceived to be a “minor procedure” with virtually no downside

    • Drug-eluting stents

      • Remove fear of restenosis as a restraint

    • Self-referral bias and profound incentives to “overtreat”

      • Supply drives demand

    • Difficult to truly assess appropriateness without full clinical data and review of the angiogram


    Potential approaches to overuse
    Potential Approaches to Overuse have CAD

    • Better education (of patients and physicians)

    • Eliminate self-referral

      • Mandatory second opinion?

      • But… would eliminate one of the key advantages of PCI

    • Reduce economic incentives

      • Pay as much for not doing angioplasty as for doing it (!)

    • Develop enforceable, evidence-based guidelines

      • Require demonstrable myocardial ischemia or evidence of myonecrosis for reimbursement


    Summary who needs a cath after a diagnosis of cad in 2007
    Summary: Who Needs a Cath After a Diagnosis of CAD in 2007 have CAD

    • Certain high risk stress test situations suggesting LMCA or 3VD as preparation for CABG

      • Purpose of cath is diagnostic rather than therapeutic

    • High Risk ACS (troponin positive, ST Segment Changes and/or high risk clinical features like CHF)

    • Patients with STEMI (as long as can be done rapidly and with trained personnel)

    • Failed medical therapy with demonstrable ischemia

    • Consider asymptomatic diabetic patients with high risk stress tests


    Who should not receive pci in 2007
    Who should have CADnot receive PCI in 2007?

    • No angina

      • Except for patients with acute STEMI or NSTEMI, PCI remains a procedure whose primary benefit is symptomatic relief

    • No ischemia

      • PCI in absence of ischemia only increases complications and costs

    • No stenosis

      • “Vulnerable plaque” remains a sexy but unproven concept

    • No hope

    Four

    “No’s”



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