Author + information
- Spencer B. King III, MD, MACC, Editor-in-Chief, JACC: Cardiovascular Interventions∗ ()
- ↵∗Address correspondence to:
Dr. Spencer B. King III, Saint Joseph’s Heart and Vascular Institute, 5665 Peachtree Dunwoody Road NE, Atlanta, Georgia 30342.
“True knowledge exists in knowing that you know nothing.”
The lead article in this issue of JACC: Cardiovascular Interventions deals with an issue I have long wondered about (1). After percutaneous revascularization is accomplished and ischemia is relieved, what is the role for beta-blocker therapy? Certainly if heart failure is present, we have evidence for beta blockade, but without heart failure or ischemia, do adequately revascularized patients need beta-blockers? This NCDR (National Cardiovascular Data Registry) study of Medicare-aged patients concludes that routine use is not needed. Despite this, the prescriptions for beta-blockers continue to increase, perhaps to comply with “optimal medical therapy.” Maybe “optimal” is not to write the prescription rather than to take the easy way out and ensure that all your ischemic heart disease patients are being prescribed all the “OMT” drugs. This paper stimulated my curiosity about the question, “What are the things that we do not know?” My former chief, Willis Hurst, once had a conversation with Eugene Stead about creating a list of the things in cardiology that everyone must know. I wonder if we could make a list of things in interventional cardiology that remain unanswered and therefore call for research of some kind to attempt to solve them. Much of our clinical research is driven by the desire to show that similar therapies are either superior to one another or at least noninferior. Much of the pharmacologic and device investigation has an economic objective, usually to justify using one similar product over another or rarely to show a cost saving for one rather than the other. Many of these studies in interventional cardiology originate from commercial interest. There are questions, however, that come up every day at morning report and the answer is, “We don’t know what is best.” I thought I would try a list and see if others might add to it or delete ones that you believe have already been answered.
Questions without answers:
1. When a 2-stent strategy is required for bifurcation lesions, what approach should be used? In a recent morning report, one operator favored an approach and always used it. Another used another approach. Others said that they selected various methods based on circumstances. Standardization is not always good, but is there room to investigate whether a default strategy should evolve, or do we wait for technology to progress further?
2. Which CTO should be treated? There is certainly a spectrum of opinion here. What is the end result that is being looked for? Patients want to live longer and better. Consensus on this issue is far from being reached.
3. Should cardiac assist devices be available for all cath labs to use in high-risk percutaneous coronary interventions (PCI) and for interventions in patients with hemodynamic impairment? An e-mail chain administered by Mort Kern recently brought a spectrum of opinions.
4. What patients should have bioresorbable scaffolds? Now that approval has been granted in the United States by the Food and Drug Administration, how will they be used? How should they be used? In Europe where they have had CE mark approval for years, the use remains low and no clear indications have been established.
5. Should transcatheter aortic valve replacement be used in low surgical risk aortic stenosis patients? Can we extrapolate from short- and intermediate-term results from high surgical risk patient investigations, or does the answer require long-term evaluation?
6. Should patent foramen ovales be closed? Will we ever have an opinion on this? If so, does it depend on the clinical and anatomical situation, or more on the bias of the physician caring for the patient?
7. Should the atrial appendage be closed in all patients with atrial fibrillation? If not, which ones? Is avoiding anticoagulation by itself reason enough?
8. Should complete revascularization be accomplished in ST-segment elevation myocardial infarction patients? In an upcoming issue of JACC: Cardiovascular Interventions, a paper looks at many studies in a network meta-analysis and concludes that staged complete revascularization is better than incomplete or multiple interventions at the time of primary PCI. Is this correct or is an adequately powered randomized test of these 3 strategies necessary? Is it possible?
9. Does PCI save lives in patients with stable ischemic heart disease? It has not been shown in previous randomized trials, but we all believe it does in certain patients. Will the ISCHEMIA (International Study of Comparative Health Effectiveness With Medical and Invasive Approaches) trial answer the question? Will a study including the coronary anatomy with the latest interventional methods be necessary?
10. How long should antiplatelet therapy be used in patients following PCI?
I told the new interventional fellows at Emory that they should pick 1 of the questions and find a way to move closer to an answer. It is tempting to think with all the progress in medicine, and in interventional cardiology in particular, that most of the answers are in. Maybe my list of 10 questions that we do not know the answers to will stimulate someone to answer them or to pose other questions. Methods for answering questions vary as much as the questions themselves. It has been emphasized that the majority of recommendations in guideline documents are based on level of evidence C (expert opinion). There are many questions here that do not achieve consensus, even without objective evidence. This does not mean that we should abandon the search for better answers. Some will be answered by randomized trials, others by observation, and some will defy answers, but when answers do not come, we should not forget the questions.
- American College of Cardiology Foundation
- Motival A.,
- Roe M.,
- Dai D.,
- Abbott J.,
- Prasad A.,
- Mukherjee D.