Do stents deserve the bad press? Mark A. Tulli MD, FACC

Transcription

1 Do stents deserve the bad press? Mark A. Tulli MD, FACC

2 Disclosures: None

3 Introduction Stents don t help people. Stents are bad for patients. Heart Treatment Overused WSJ Study Finds Doctors Often Too Quick to Try Costly Procedures to Clear Arteries Unnecessary Stent Procedures MORGAN&MORGAN

4 Introduction Misinterpretation of the data Misinformed patients/doctors Poor perception of CAD as a plumbing problem see a blockage, fix a blockage Has led to confusion about the merit of stents and overuse of stents.

5 Goals: Understanding the data will lead to confidence in the clinical benefit of stents in treating your patients. Understand Fractional Flow Reserve (FFR) as part of the physiologic assessment of coronary stenoses. Learn about how physiologic assessment of stenoses is a more accurate way to determine the need for stents.

6 Background From Stents, by Ryan Colombo, Openwetware Feb 2015.

7 Background It has been clearly demonstrated in patients with acute coronary syndromes, percutaneous coronary intervention (PCI) is superior to medical therapy. In patients with stable coronary disease, trials have not demonstrated a mortality benefit with stents over optimal medical therapy alone. Seminal COURAGE trial 2007 lead to the vilification of stents in the press incorrectly and it was identified that cardiologists were implanting stents in patients where there may be no or little clinical benefit. WHY Bavry AA1, Kumbhani DJ, Rassi AN, Bhatt DL, Askari AT. Benefit of early invasive therapy in acute coronary syndromes: a meta-analysis of contemporary randomized clinical trials.j Am Coll Cardiol Oct 3;48(7): Epub 2006 Sep 12. Boden WE Optimal medical therapy with or without PCI for stable coronary disease. N Engl J Med Apr 12;356(15): Epub 2007 Mar 26.

8 Reason #1 Eliot Freidson identified traits that characterize the typical clinician leading to unintentional overuse of stents: We believe in what we are doing. When things go right, we take the credit. We prefer action to inaction. Even action with little chance of success is preferred over no action at all. We are pragmatic. We see apparent cause-effect relationships even in the absence of any theoretic foundation. We are highly subjective. We depend more on gut feelings than on book knowledge. We emphasize uncertainty in our defense. When things go wrong, it is not our fault. Because we deal with individuals rather than groups, we cannot rely on epidemiologic concepts or probabilities derived from population statistics. George A. Diamond, MD, FACC; Sanjay Kaul, MD, FACC COURAGE Under Fire On the Management of Stable Coronary Disease J Am Coll Cardiol. 2007;50(16): doi: /j.jacc

9 Reason #2 There are limitations to seeing lesions on angiography: lumenography. We can only see where the contrast fills the lumen. We cannot see the entire vessel structure or predict the exact luminal narrowing percentage. In the case of an intermediate borderline lesion (40-70% on angiography), some may be severely obstructing bloodflow, yet others are not obstructing bloodflow. While clinicians feel they are doing the right thing in treating stable CAD with stents (action is better than inaction), perhaps the angiographic lesions are not obstructing bloodflow severely and the angiogram is deceptive. It is difficult to tell doctors and patients Just because you have a blockage doesn t mean it needs to be fixed

10 COURAGE trial COURAGE (Clinical Outcomes Utilizing Revascularization and Aggressive Drug Evaluation) trial enrolled patients with chronic stable angina and at least 1 significant ( 70%) angiographic coronary stenosis who were randomly assigned to an initial treatment of either PCI in conjunction with optimal medical therapy or optimal medical therapy alone. COURAGE demonstrated that low risk patients with stable angina can be safely treated with optimal medical therapy, with outcomes better than stenting these low risk patients. This is an angiographic directed stenting trial

11 Not all blockages require fixing Fractional Flow Reserve (FFR) has been developed to identify high risk stenoses with significant flow obstruction. FFR is a tool that evaluates the physiology of blood flow through an artery. It can directly determine the quantity of blood flow past a stenosis. FFR is a stress test on the cath lab table. Adenosine is given to obtain the maximum blood flow distal to the stenosis. A pressure transducer near the end of a coronary wire is placed distal to the stenosis. Using a calculation involving this distal pressure and proximal pressure can establish a gradient that can determine any flow restriction during exercise.

12 Fractional Flow Reserve Tom Watson, BS, RCVT, Cardiac Pressure: To Stent or Not to Stent, June 6, 2013 :

13 FFR >0.80 not flow limiting, <0.80 is severely obstructing flow. Matar, F, Cath lab Digest, Volume 15 - Issue 11 - November, 2007

14 FAME Flow Chart 2-Year Follow-Up of the FAME (Fractional Flow Reserve Versus Angiography for Multivessel Evaluation) Study Am Coll Cardiol. 2010;56(3): doi: /j.jacc

15 FAME results Outcomes were better if stenting was directed by FFR compared to angiographic measurements. 2-Year Follow-Up of the FAME (Fractional Flow Reserve Versus Angiography for Multivessel Evaluation) Study Am Coll Cardiol. 2010;56(3): doi: /j.jacc

16 FAME Trial FAME started the discussion that not every stenosis that appears severe is actually physiologically significant. FAME demonstrated the superiority of FFR-guided PCI over angiography-guided PCI In COURAGE, revascularization was guided by the angiographic severity of the lesions, not FFR So what if we designed a COURAGE type of trial but only for patients with demonstrated severe ischemia.

17 FAME 2 Study Design Stable CAD patients scheduled for 1, 2 or 3 vessel DES-PCI N = 1220 Randomized Trial FFR in all target lesions Registry At least 1 stenosis with FFR 0.80 (n=888) When all FFR > 0.80 (n=332) Randomization 1:1 PCI + MT 73% MT 27% MT 50% randomly assigned to FU Follow-up after 1, 6 months, 1, 2, 3, 4, and 5 years

18 Primary Outcomes FAME 2 Cumulative incidence (%) No. at risk MT PCI+MT Registry PCI+MT vs. MT: HR 0.32 ( ); p<0.001 PCI+MT vs. Registry: HR 1.29 ( ); p=0.61 MT vs. Registry: HR 4.32 ( ); p< Months after randomization De Bruyne B, Pijls NH, Kalesan B, et al., on behalf of the FAME 2 Trial Investigators. Fractional flow reserve-guided PCI versus medical therapy in stable coronary disease. N Engl J Med 2012;367: See more at: /09/01/07/21/FAME-II#sthash.0WESFgH4.dpuf

19 FAME 2 The reason there is a discrepancy between FAME 2 and COURAGE is that FAME 2 only included truly ischemic lesions, not just those that were angiographically significant as in the COURAGE trial. We can also conclude that patients with a negative FFR >0.80 (not ischemic), can be safely treated with optimal medical therapy.

20 Conclusion: Stents have always been better than medical therapy in acute coronary syndrome and myocardial infarction. Medical therapy is safe to treat low risk stable angina with CAD and low or no ischemic burden on stress testing. Medical therapy is safe to treat stable angina with CAD and FFR >0.80. If patient failed medical therapy, its appropriate to then perform PCI.

21 Conclusion: Patients with CAD, high risk ischemia and stable angina are best managed with PCI vs. medical therapy. Fractional Flow Reserve is more accurate than angiography at distinguishing severe obstructions from nonobstuctive stenoses. Stenoses with FFR <0.80 and stable angina has better outcomes with stenting and optimal medical therapy compared to optimal medical therapy alone.

22 Conclusion: Do stents deserve the bad press? NO, but it has been beneficial to bring awareness to the medical community and improve treatment of this #1 killer