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Primary Angioplasty at Community Hospitals in the 21st Century:A Commentary
In an effort to maintain a balanced national sense on this issue that has cardiologists divided in their opinions, it seems critically important to make the nurses, technicians and other healthcare professionals who constitute the infrastructure so essential to the performance of interventional procedures (PCI) aware of more moderate views and why the solution as proposed by Wharton et al is likely the wrong one. First of all, the national bodies of organized cardiology that set standards of practice and promulgate guidelines have always intended that these procedures, the outcomes of which are extremely dependent on operator experience, be done in Angioplasty Centers. These are institutions that have not only the size and patient-base to guarantee adequate volumes, but also the commitment of resources and a proven record of success in similar undertakings (i.e. cardiac surgery) to optimize the likelihood of favorable patient outcomes. The term surgical back-up became the surrogate for all these qualities and implied far more than the narrow sense in which it is used by Wharton at el. A segment of the interventional community is anxious to see a broader expansion of PCI into the community but they seem to argue as if all institutions are citadels of excellence and differ only by whether they are the haves or have-nots by virtue of having cardiac surgery or not. It was with this understanding of Angioplasty Centers, a.k.a. as surgical centers, that the national standard of practice has always held that angioplasty procedures in the U.S. be limited to institutions with in-house cardiac surgical programs.1,2 From its earliest days, this policy was attacked on the same grounds as the Wharton argument that countless procedures have been done all throughout Europe without surgical backup and no difference in outcomes are noted. The answer then, as now, is the same; in addition to basic philosophical differences between the United States and other countries regarding patient care, there are major differences in the number of laboratories and the number of operators per laboratory throughout these state-regulated facilities in Europe. Being far fewer than in the US, it is rare to encounter either a low volume institution or low volume operator. Additionally with a population base one-fifth that of the U.S. and a geographical area only a fraction of that of the U.S., accountability, oversight and regulation of laboratory performance is more readily accomplished in these countries. It is of note that when you ask European operators which system they prefer, the answer is almost invariability, angioplasty with surgical back up. The main issue raised by the article appears to center around Primary Angioplasty. This is somewhat difficult to understand because the Guidelines have recognized since 1996 that there are risk/benefit considerations that enter into the management of acute MI patients that would warrant the performance of Primary PCI in community hospitals without surgery on-site. Indeed, the authors accurately quote the latest AHA/ACC Guidelines3 that ¦primary PTCA should be performed in centers with cardiac surgical capability or in those institutions with a proven plan for rapid access to cardiac surgery in a nearby facility. The Guidelines do specifically recommend primary PTCA in patients who are ineligible for fibrinolysis due to bleeding risks. Similarly, since 40% of patients in cardiogenic shock require revascularization by CABG, it would seem inappropriate to consider undertaking such cases in non-surgical centers. In brief, the vast middle ground that Wharton claims is not addressed in the present Guidelines is inaccurate and overlooks the fact that no convincing data are available to demonstrate that PTCA is superior therapy for non-ST elevation MI, in the advanced elderly, in those with non diagnostic ECGs or in patients in whom fibrinolytic therapy has failed. The major strength of the article is its emphasis and detail on what it takes to create a successful primary angioplasty program. This labor-intense process holds true whether or not it is at a hospital with its own cardiac surgical program or not. Often overlooked, however, in a community hospital without its own surgical program, is the scope of the experienced support staff that is required. It includes not only cath lab personnel but CCU nurses, blood bank and other laboratory technicians as well as the extensive and expensive investments required of the institution. This goes beyond the conventionally expensive interventional imaging equipment and includes a large inventory of expensive catheters, wires and stents to say nothing of the economics involved in staffing a cath lab with a 24 hour, 7 days a week on-call schedule. My criticisms of the article can be generalized into two categories: 1) The Certainty of It All and 2) The Tone of It All. The Certainty of It All: Less than 3,000 patients are enrolled in all ten randomized controlled trials: all of the studies, as well as the subsequent meta-analysis by Weaver4, are underpowered and rely on combined variables for the primary endpoint. As such, the conclusions have to be interpreted with caution and hardly constitute conclusive evidence that primary PTCA is the superior therapy. The largest of the randomized trials, GUSTO IIb,5 showed a less powerful advantage of primary PTCA over thrombolytic therapy and it was not present six months later. Additionally, 18% of patients randomized to PTCA in that study did not receive the procedure and they had a 14% thirty-day mortality. The data are not reproducible in the community based on at least three large registry studies.6“8 The majority of patients with acute ST segment elevation MI do not have bleeding risks that constitute a true contraindication to fibrinolytic therapy. There is no convincing evidence that PTCA is superior in the management of patients with acute MI who: a) present late, b) had prior CABG, c) have a non-diagnostic ECG or d) left bundle branch block and e) in the advanced elderly. The Tone of It All: To suggest morphine and bed rest is the current alternative therapy to primary PTCA in acute MI is to be as deceptive as claiming all community hospitals that offer primary PTCA as first line therapy performed well over 36 procedures per year. To claim there are unfounded statutes preventing a qualified physician from doing what is necessary to save the life of a critically ill patient is a distortion of the facts that has an inflammatory and unhelpful ring to it. Conclusion: Immediate coronary angiography with primary PTCA as the planned therapy if suitable, can be safe and effective in the management of acute myocardial infarction patients at select community hospitals without cardiac surgery. It should not, however, be offered as the national standard-of-care of patients with acute MI because neither its efficacy nor its broader applicability has been suitably demonstrated in appropriately powered trials. The current national guidelines should remain substantively unchanged.
<b>References</b>
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2. Ryan TJ, Bauman WB, Kennedy JW, et al. Guidelines for percutaneous transluminal coronary angioplasty: A report of the American Heart Association/American College of Cardiology Task Force on assessment of diagnostic and therapeutic cardiovascular procedures (Committee on Percutaneous Transluminal Coronary Angioplasty). Circulation 1993;88:2987–3006.
3. Ryan TJ, Antman EM, Brooks NH, et al. 1999 update: ACC/AHA guidelines for the management of patients with acute myocardial infarction. A report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Committee on Management of Acute Myocardial Infarction). J Am Coll Cardiol 1999;34:890–911.
4. Weaver WD, Simes J, Betriu A, et al. Comparison of primary coronary angioplasty and intravenous thrombolytic therapy for acute myocardial infarction. JAMA 1997;278:2093–2098.
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8. Every N, Parsons L, Hlatky M. et al. A comparison of thrombolytic therapy with primary coronary angioplasty for acute myocardial infraction. N Engl J Med 1996;335:1253–60.