Feature

Is it Time for Qualified Community Hospitals to Consider Non-Emergent Coronary Intervention without Cardiac Surgery?

Thomas P. Wharton Jr., MD, FACC, Nancy Sinclair McNamara, RN, BSN From the Division of Cardiovascular Services Exeter Hospital, Exeter, New Hampshire
Thomas P. Wharton Jr., MD, FACC, Nancy Sinclair McNamara, RN, BSN From the Division of Cardiovascular Services Exeter Hospital, Exeter, New Hampshire
PLEASE CLICK ON IMAGES FOR LARGER SIZE A diagnosis of non-q-wave myocardial infarction was made and he was treated with aspirin, heparin, oxygen, nitropaste, intravenous and oral metoprolol, and eptifibatide. His pain and his hypertension were well-controlled. He was admitted for further evaluation. The following day he developed chest discomfort and his EKG revealed mild anterior T inversion. Cardiac catheterization was advised. After consenting to cardiac catheterization with possible coronary intervention, William was brought to the cath lab. Coronary angiography revealed single-vessel coronary artery disease with a 99% stenosis of the left anterior descending artery after a large septal and diagonal branch with slow (TIMI grade II) flow (Figure 1, left image). Primary stenting was performed without complication, with an excellent result, no residual stenosis and brisk (TIMI grade III) flow (Figure 1, right image). A left ventriculogram was performed which demonstrated anteroapical hypokinesis, no mitral regurgitation, and an ejection fraction of 50%. He returned to the progressive care unit where his arterial sheath was removed 3 hours later.* He remained pain free, was seen in consultation by cardiac rehab consult, and was discharged the next morning on aspirin, clopidogrel, metoprolol, fenofibrate, ramipril. Plans were made for him to reunite with his primary care provider and to join phase II of the cardiac rehabilitation program at his local hospital. He returned to work two weeks later. At 5 months follow-up, William is working full-time. He is being followed by his cardiologist. He has completed the cardiac rehab program. Recently, his wife said in telephone follow-up, William is active in the local gym and remains on all of his medications. We are so thankful that we were in the right place at the right time when he had his heart attack. *Subsequent to this case, the cath lab at Exeter Hospital began using the Syvek® patch for in-lab sheath removal for interventional patients that are heparinized and receiving GP IIb/IIIa platelet inhibitors with an activated clotting time of Most patients with acute coronary syndromes such as William present to community hospitals. Should every patient with unstable angina or non-ST-elevation myocardial infarction that needs a cardiac catheterization be transferred to a surgical center in case coronary intervention is needed? What if the community hospital is already experienced in primary angioplasty, with high-volume interventionalists and cath team and the most current interventional equipment? If the catheterization is performed on site and reveals a culprit lesion that requires intervention, such as in William™s case, should the procedure be stopped and the patient be transferred to a surgical center? Even if the lesion is a type A (low risk) lesion and the patient is not at high clinical risk? Is the risk of intervention at the time of catheterization any greater than the risk and delay of transfer? If not, is the increased length-of-stay and cost of a second hospital admission justified? And why should William™s wife, now staying at a local hotel, feeling alone and concerned for her husband, be subjected yet again to a different hospital with different staff and cardiologists in a different city? Isn™t it highly desirable to treat a cardiac patient completelywith a single invasive procedure rather than two separate ones? Introduction: Primary Percutaneous Coronary Intervention Is Safe and Effective at Hospitals Without Cardiac Surgery Primary percutaneous coronary intervention (PCI) is now the therapy of choice for acute myocardial infarction (AMI) at qualified centers. More and more community hospitals without on-site cardiac surgery programs are starting to offer primary PCI, for several reasons:1 Primary PCI reduces death, stroke, recurrent ischemia, and reinfarction compared to fibrinolytic therapy;1-5 A majority of patients with AMI are not candidates for lytic therapy, and are generally at higher risk than lytic-eligible patients;6,7 A majority of patients with AMI present to community hospitals rather than tertiary surgical centers;8 It has been very clearly demonstrated in the literature, most recently by Dr. Tom Aversano™s randomized C-PORT trial of primary PCI vs. lytic therapy at non-surgical hospitals9 (which is the second-largest such randomized trial ever performed) that qualified community hospitals without cardiac surgery can offer primary PCI safely and effectively, with outcomes that are comparable to those of high-volume tertiary centers, and better than outcomes with lytic therapy. (Please refer to our article in the November edition of Cath Lab Digest, Primary Angioplasty At Community Hospitals In the 21st Century, along with the commentary by Dr. Tom Ryan and our response to this commentary in the December edition.) The Question of Non-Emergent PCI at Community Hospitals Since, as we demonstrated in the above article, qualified community hospitals have demonstrated excellent outcomes with primary angioplasty in acutely ill patients with AMI, it is logical to postulate that such hospitals could also perform non-emergent PCI safely and effectively in patients that are more stable without on-site cardiac surgical backup. This is clearly a controversial issue in the US:1 Unlike patients with AMI, non-emergent patients can theoretically be transferred safely to a surgical institution for PCI;2 Guidelines and state regulations in the U.S. have mandated against this practice because of the risk that complications of PCI will create a surgical emergency;3 There are strong economic considerations involved on both sides of this question. The risk of PCI causing a surgical emergency was 5.8% in the 1977-1981 NHLBI registry and 3.5% in the 1985-1986 NHLBI registry. Hence standards then evolved that PCI should be performed only with in-house surgical standby. However, newer generation stents and GP IIb/IIIa platelet inhibitors have lowered the risk of vessel closure to 0.4% in the current era.10-13 Since the need for emergency bypass surgery because of a complication of PCI has now been reduced 10-fold, the old rules regarding surgical standby no longer need apply. Coronary Intervention at Non-Surgical Hospitals Is Becoming An Accepted Standard Of Care Throughout The World Germany, France, and Italy have a long history of not requiring bypass surgery at centers that perform PCI. The new British Cardiac Society and British Cardiovascular Intervention Society together recently issued new guidelines for PCI which include non-surgical hospitals in the United Kingdom14 partially as a result of the program at (ironically) Exeter, England. These guidelines now allow both emergent and elective angioplasty to be performed at hospitals without on-site cardiac surgery, provided that they otherwise meet standards of care and have systems in place to enable patients to be on cardiopulmonary bypass within 90 minutes of calling the cardiac surgeon. Holland and Australia have also recently changed their regulations to allow PCI at non-surgical hospitals. ------------------------------------------------------------------------------------------------- Table 1. Rates of emergency bypass surgery and mortality for 54,379 patients undergoing PCI at hospitals with and without onsite cardiac surgery in France: 62% of centers did not have cardiac surgery.12 Centers With Surgery Centers Without Surgery Emergency Bypass Surgery 0.44% 0.25% Mortality 0.72% 0.41% ------------------------------------------------------------------------------------------------- Angioplasty at hospitals without surgical backup is quite common in Europe, with outcomes that equal those of surgical hospitals.12,15-24 For example, a large registry of over 50,000 patients undergoing intervention in France recently reported no differences in the outcomes of centers with and without cardiac surgery,12 with less than 0.4% of patients requiring emergency surgery: 0.44% of patients at surgical hospitals and 0.25% of patients at non-surgical hospitals were sent for emergency bypass (Table 1). Two-thirds of the hospitals in this registry did not have on-site surgical facilities. The mortality at surgical hospitals was 0.7%; at non-surgical hospitals it was only 0.4%. Thus the non-surgical hospitals in this very large registry sent fewer patients to emergency surgery and had fewer deaths! There are at least eight other registries of PCI without on-site surgery, from Canada, the United Kingdom, Germany, and Italy.15-24 These report outcomes of an aggregate of over 70,000 patients undergoing non-emergent angioplasty at hospitals without in-house surgery. The overall mortality, pooling data from all of these series, was 0.48%. Clinical Benefits Of Performing Non-Emergent PCI At The Time Of Diagnostic Catheterization At Non-Surgical Hospitals Despite the contention that there is no justification for extending non-emergent PCI to qualified community hospitalseven those that have a proven track record in the performance of primary PCIthere are in fact many potential clinical benefits to be gained from this practice (Table 2). This practice would obviate the need for a second procedure and thus reduce morbidity (no additional groin puncture, less contrast and radiation, far less total procedure time). Further, time is of the essence for patients with acute coronary syndromes. In unstable patients, the wait for transfer alone carries a small but real risk that the coronary artery might occlude while waiting, causing an MI. Thus the risk and delay of transfer to a surgical center might exceed the risk that the procedure itself would cause an MI. For example, the recently reported Treat angina with Aggrastat and determine Cost of Therapy with an Invasive or Conservative Strategy (TACTICS-TIMI 18)25 trial found that patients treated with GP IIb/IIIa platelet inhibitors and early coronary angiography with PCI when appropriate, within 4“48 hours of presentation, had a reduction in the composite of death, AMI, or rehospitalization for recurrent unstable angina at 6 months, compared to a more conservative ischemia-guided approach. In addition, patient satisfaction would be increased and the primary care physician could remain involved with care of her/his patient through its completion. The emotional discomfort due to interruption of care and transfer to unfamiliar surroundings for a second procedure would be avoided. To illustrate these problems, we have reprinted here excerpts from three letters that we have received from other sites regarding this problem (Figures 3“5). Finally, the performance of ad hoc PCI at the time of diagnostic catheterization at hospitals without on-site cardiac surgery will definitely increase interventional volumes at centers that now offer only primary angioplasty. This should further improve individual and institutional competencies and patient outcomes.26 ----------------------------------------------------------------------------------------------------------- Table 2. Benefits of Performing Non-Emergent PCI at Hospitals Without On-Site Cardiac Surgery 1. Obviates the need for a second procedure and thus reduces morbidity (no additional groin puncture, less contrast and radiation, far less time). 2. In unstable patients, the wait for transfer alone carries a small but real risk that the coronary artery might occlude while waiting, causing an AMI. Thus the risk of waiting for transfer of such patients to a surgical center may exceed the risk of the procedure itself. 3. Since true surgical standby (open O.R. and surgical team ready and waiting) is rarely practiced, the time delay from cath lab to O.R. may be the same as for "in-house: accidents at surgical centers.30 4. Patient and family satisfaction will be increased. 5. The Primary Physician can remain involved in the care of his/her patient through its completion. 6. Interventional volumes will be increased at centers which now offer only primary PTCA, which should further enhance outcomes. 7. With the aging of the "baby boomers," PTCA volumes will continue to grow; uncoupling PTCA from surgery will reduce the pressure to build new low-volume surgical programs to support PTCA programs.27 8. Decreases length-of-stay by 24-48 hours and obviates the need for a second admission or transfer. This can reduce total charges by $15,000 to $20,000. 9. Cardiac cath is now performed at 850 hospitals in the US that do not have cardiac surgery. Patients needing PCI must either be discharged and readmitted to a surgical hospital or be transferred by ambulance. 10. Assuming that 10 patients per month per hospital need PCI after cath at each of these 850 cath labs without surgery, and that the total additional cost of delay and transfer and a second procedure is $10,000: The potential cost savings of PCI at the time of diagnostic cath at just half of these non-surgical hospitals might be 500 million dollars per year. ----------------------------------------------------------------------------------------------------------- Economic Benefits Of Performing Non-Emergent PCI At The Time Of Diagnostic Catheterization At Non-Surgical Hospitals Consider that diagnostic catheterization is now performed at around 850 hospitals in the United States that do not have cardiac surgery programs. When an elective or urgent patient is found to need angioplasty at the time of a diagnostic catheterization at such a hospital, the usual practice is either to discharge the patient and later readmit the patient to a surgical center for angioplasty or transfer the patient via ambulance. Clearly this practice is quite costly. Angioplasty at the time of diagnostic catheterization at non-surgical hospitals will decrease the length-of-stay by 24“48 hours and obviate the need for a second admission or transfer. This can reduce total charges dramatically. In our northern New England region, the extra charges for readmission or transfer to a surgical center for angioplasty and an overnight stay are at least $20,000 per patienthighly problematic especially if the patient is self-pay. Cardiac catheterization is now performed at 850 hospitals in the US that do not have cardiac surgery. Patients needing PCI must either be discharged and readmitted to a surgical hospital or be transferred by ambulance. Assuming that 10 patients per month per hospital need PCI after cath at each of these 850 cath labs without surgery, and that the total cost of delay and transfer and a second procedure is at least $10,000, the potential cost savings of performing PCI at the time of diagnostic cath at just half of these non-surgical hospitals might be 500 million dollars per year! Finally, the number of PCI procedures performed in the US will continue to grow dramatically, due both to the aging of the baby boomers,27 and to the increasing application of PCI in patients with AMI and other acute coronary syndromes (cf. TACTICS study, described above,25), as well as to patients with more complex coronary anatomy. The need for more interventional facilities will increase faster than the need for more surgical facilities, which has in fact reached a plateau in recent years. Thus uncoupling PCI from cardiac surgery will reduce the pressure to build new low-volume surgical programs to support interventional programs.28 Is There An Increased Delay In Transferring Emergencies to the Operating Room with Off-Site Surgical Backup? True surgical standby is very rare nowadays at most surgical institutions. Instead of having an operating room open, empty, and waiting, and surgeon and staff unoccupied and waiting for several hours (which is extremely costly and wasteful for a procedure that will be needed only 0.4% of the time), most operating rooms at busy surgical centers are busy most of the time. Thus, the patient who suffers the rare cath lab accident in house may face a waiting time of two to three hours or more for the next available room to empty12,29-31 a delay that should not be any longer than for a patient to be transferred from an outlying hospital, if appropriate protocols and transfer agreements are in place. For example, in a study from Ireland, the delay to revascularization was 270 minutes, and the delay was the same whether the angioplasty complication occurred at the facility without surgery or the facility where the surgery was performed. In this study, the length of the delay was primarily dependent on when the next operating room became available. The authors conclude, The absence of immediate surgical help did not influence the outcome in any patient.30 Another similar study from the UK concluded: Delays in operating on stable patients in centers which operate a ˜next available theatre™ backup policy may not differ from some units performing PCI with offsite cover for PCI complications.31 Volume Considerations One of the reasons often given to sustain the requirement for on-site surgery as a prerequisite to performing primary angioplasty is that non-surgical hospitals will likely have lower interventional volumes, and that higher institutional volumes mean better outcomes. Thus in the view of many, the requirement for on-site surgery has become largely a surrogate requirement.32 The cardiologists that perform intervention at non-surgical hospitals are not necessarily low-volume operators, since they may also perform intervention at surgical centers. We agree that they should not be low-volume operators. Regarding institutional volumes, hospitals that perform only 3 to 4 primary interventional procedures per month in patient with AMI have better outcomes than those that perform fewer.9,33-35 This is a number that is commonly performed by the community hospitals that we have worked with. Also, remember that a smaller hospital that performs only 200 interventions per year usually has only one cath lab and one cath team, and only two to three interventionalists. Thus smaller hospitals may perform as many cases, on a per-operator and per-team basis, as larger hospitals with more cath lab teams. The data to support the contention that angioplasty should be restricted to higher-volume centers are not convincing. For example, in the ACC clinical competence statement for interventional procedures, Dr, John Hirshfield et al. note that the studies of outcomes vs. procedural volumes cited therein took place before the era of stents and platelet GP IIb/IIIa inhibitors, and observe, It is likely that the availability of these treatments has reduced the expected frequency of death and emergency coronary artery bypass graft (CABG) surgery¦ Consequently, these data may not accurately reflect current practice¦36 In fact, of 7 older studies,37-43 three38,39,41 report no association of risk-adjusted mortality with hospital volume. Two others42,43 report on specific years in California™s Office of Statewide Health Planning and Development (OSHPD) database and are superceded by the more comprehensive and more recent report by Dr. Vivian Ho that we discuss below.44 In one of these two reports, Ritchie et al report no statistically significant difference in in-hospitals mortality between hospitals that perform 400 procedures per year;42 in the other, Rill et al. report only a 0.3% mortality advantage for PTCA procedures at hospitals that perform >200 interventions per year, but a 0.2% mortality disadvantage for stent procedures at these higher-volume hospitals compared to those that perform 400/yr. This difference in mortality of only 0.4% was not even risk-adjusted; patients with AMI were included in this database. Very importantly, the lower volume hospitals in this study performed significantly more procedures in patients with evolving AMI: 31.3% of patients had AMI in hospitals performing 400 P angioplasties/yr. Thus the lower-volume hospitals saw a significantly higher-risk population. The authors acknowledge that one weakness of their study is the use of administratively collected data (OSHPD discharge data collected from discharge abstracts). In addition, Dr. Edwin Huff, in a letter to the New England Journal of Medicine, noted that for New Hampshire Medicare data, lower-volume hospitals were far more likely to perform intervention on patients with a diagnosis of AMI. Huff went on to point out that many reports of outcomes vs. volume do not use risk-adjusted data [such as the above], and thus have disregarded robust risk factors that explain most of the variation in outcome attributed to hospital volume.45 In another recent report of outcomes of 6,635 patients undergoing angioplasty at hospitals in Canada, there was no significant difference in adjusted rates of repeat revascularization, recurrent MI or death at six months between hospitals doing less than 200 procedures per year and more than 400 procedures per year.46 Lastly, a very recent report of Medicare outcomes for 1997 by McGrath et al. demonstrated that, for higher-volume operators, the adjusted combined rate of CABG and 30-day mortality at hospitals that performed between 80 and 160 Medicare procedures per year was only 0.6% higher than at hospitals that performed more than this number.47 Importantly, also in this report, lower-volume hospitals were more likely to perform intervention on patients admitted with a diagnosis of AMI (34.5% vs. 25.9%) This higher incidence of patients with AMI at lower volume hospitals is similar to the findings of Ho44 and Huff45 noted above, and again suggests that a high proportion of low volume hospitals perform angioplasty primarily for patients with evolving AMI. While McGrath et al. did try to adjust for co-morbidities such as AMI, they note that their risk adjustment is limited to those characteristics that are available through Medicare claims. It is difficult to assure that risk adjustment based on administratively collected data can be adequately accomplished when the incidence of such a major risk predictor as AMI was 33% higher in the lower-volume hospitals. Newer studies like these lend very little justification to the assertion that there is still a clinically important relationship between institutional volume and outcomes in this era of stents and IIb/IIIa platelet inhibitors. As noted by Jollis et al.,¦ the absolute differences in outcomes across volume strata are small. Some may view these differences as statistically, but not clinically, relevant.48 In view of the superiority of primary angioplasty as treatment for AMI, and in view of the public health benefit to be gained by its increased availability, strict limitation of angioplasty to high-volume hospitals would effectively eliminate the possibility that primary angioplasty could be offered at most community hospitals ven at those that perform it now, and perform it well. We would hope that the new ACC/AHA PTCA guidelines which are now under revision will take into account the considerations regarding institutional volumes and outcomes that we present here. New Evidence Which Supports the Safety and Efficacy of Non-Emergent PCI at Community Hospitals without On-Site Surgery in the US This past November 2000, we presented to the Scientific Sessions of the American Heart Association an abstract of the pooled outcomes of 2,645 patients having non-emergent PCI from 11 US hospitals without cardiac surgery on site.49 We accepted into the registry all hospitals that volunteered to submit data, without pre-screening for outcomes. These hospitals followed criteria such as those that we have proposed for operators, cath team, equipment, and a formalized surgical back-up arrangement (see Tables 6 and 7 of our article, Primary Angioplasty at Community Hospitals in the 21st Century, in Cath Lab Digest, November, 2000, p. 12.). Hospitals in this registry were selective, and did not perform PCI on site in all cases. Patients with both high clinical risk and high angiographic risk features were instead referred for PCI at a surgical center, based on the recommendations of Meier50 (Tables 3, 4). Thirty-nine operators at these 11 hospitals performed non-emergent PCI on 3,297 lesions in the 2,645 patients, with a mean of 1.25 lesions per patient. The mean annual operator volume (also including primary PCI and cases performed at surgical centers) was 109 procedures, with a range of 45 to 339; 67% of operators performed >75 procedures/yr. A majority of the operators at 10 of the 11 hospitals performed at least this number. The mean annual institutional PCI volume of the 11 hospitals was 196 procedures, with a range of 101 to 295. PCI was elective in 46%; the rest had unstable angina but not evolving AMI. Pts with both high clinical risk and high angiographic risk features were instead referred for PCI at a surgical center. The updated outcomes presented (Table 5) included a procedural success rate of 96.5%; multivessel intervention was performed in 16%. Stents were used in 81% and GP IIb/IIIa platelet inhibitors in 61%. Only ten pts (0.4%) were transferred emergently to a surgical center because of a procedural complication. Non-fatal q-wave AMI occurred in 0.1%; in-hospital reocclusion in 0.7%; bleeding requiring transfusion in 1.1%; stroke in 0.1% (non-hemorrhagic). In this population, in which 54% had unstable angina, the in-hospital mortality was extremely low at 0.1%. Major adverse events (death, q-wave AMI, and stroke) occurred in 0.31%. The rates of clinical success, emergency CABG, and death in our registry were very similar to those of the Northern New England (NNE) PCI registry for non-emergent PCI procedures at 6 high-volume surgical hospitals in 199751 (Figure 6). Conclusion Non-emergent coronary interventional procedures in appropriately selected patients can be safe and effective at qualified hospitals without cardiac surgery, with outstanding outcomes that compare quite favorably to those currently reported from tertiary surgical centers. We believe that the clinical and economic advantages of this approach are quite compelling. We would echo the prophetic words of Dr. John Vogel in his 1993 textbook, The Practice of Interventional Cardiology: [With] improved operator technique, low complication rates, increased awareness of patient risks, improved characterization of morphologic and anatomic factors, and the development of new technological tools¦active surgical standby can be markedly reduced, thereby resulting in enormous cost reductions and more appropriate patient care.52
References
References1. Weaver WD, Simes J, Betriu A, et al. Comparison of primary coronary angioplasty and intravenous fibrinolytic therapy for acute myocardial infarction. JAMA 1997;278:2093-2098.2. Zijlstra F, Beukema WP, van’t Hof AW, et al. Randomized comparison of primary coronary angioplasty with thrombolytic therapy in low risk patients with acute myocardial infarction. J Am Coll Cardiol 1997;29:908-912.3. Zijlstra F, Hoorntje JC, de Boer MJ, et al. Long-term benefit of primary angioplasty as compared with thrombolytic therapy for acute myocardial infarction. N Engl J Med 1999;341:1413-1419.4. Zahn R, Schiele R, Gitt AK, et al. Primary angioplasty is superior to intravenous thrombolysis in all subgroups of patients: results of 9906 patients with acute myocardial infarction [abstract]. Circulation 1999;100:I-359.5. Schömig A, Kastrati A, Dirschinger J, et al. Coronary stenting plus platelet glycoprotein IIb/IIIa blockade compared with tissue plasminogen activator in acute myocardial infarction. N Engl J Med 2000;343:385-391.6. Rogers WJ. Contemporary management of acute myocardial infarction. Am J Med 1995;99:195-206.7. Rogers WJ, Bowlby LJ, Chandra NC, et al. Treatment of myocardial infarction in the United States (1990 to 1993). Observations from the National Registry of Myocardial Infarction. Circulation 1994;90:2103-2114.8. Aversano T. Smaller hospitals without onsite surgical backup can perform PCI: C-PORT data. Internet interview and report of press conference, , November 16, 2000.9. Aversano T, et al. Atlantic cardiovascular patient outcomes research team trial of primary percutaneous coronary intervention vs thrombolysis in acute MI (C-PORT PCI). Presented at the 73rd Scientific Sessions of the American Heart Association, New Orleans, LA, November 15, 2000.10. Stone GW, Brodie BR, Griffin JJ, et al. Prospective, multicenter study of the safety and feasibility of primary stenting in acute myocardial infarction: in-hospital and 30-day results of the PAMI stent pilot trial. Primary Angioplasty in Myocardial Infarction Stent Pilot Trial Investigators. J Am Coll Cardiol 1998;31:23-30.11. Antoniucci D, Santoro GM, Bolognese L, et al. A clinical trial comparing primary stenting of the infarct-related artery with optimal primary angioplasty for acute myocardial infarction. Results of the Florence Randomized Elective Stenting in Acute Coronary Occlusions (FRESCO) trial. J Am Coll Cardiol 1998;31:1234-1239.12. Loubeyre C, Morice MC, Berzin B, et al. Emergency coronary artery bypass surgery following coronary angioplasty and stenting: results of a French multicenter registry. Cathet Cardiovasc Intervent 1999;48:441-448.13. Stone GW, Brodie B, Griffin J, et al. "Role of cardiac surgery in the hospital phase management of patients treated with primary angioplasty for acute myocardial infarction." Am J Cardiol 2000;85:1292-6.14. Joint Working Group on Coronary Angioplasty of the British Cardiac Society and British Cardiovascular Intervention Society. Coronary angioplasty: guidelines for good practice and training. Heart 2000;83:224-235.15. Klinke WP, Hui W. Percutaneous transluminal coronary angioplasty without on-site surgical facilities. Am J Cardiol 1992;770:1520-1525.16. Reifart W, Schwarz F, Preusler W, Stoerger H, Hofmann M. Results of PTCA in more than 5,000 patients without surgical standby in the same center [abstract]. J Am Coll Cardiol 1992;19:229A.17. Ribichini F, Uslenghi E, Picco L, et al. Elective coronary angioplasty in total absence of heart surgery. G Ital Cardiol 1994;24:949-956.18. Baduini G, Belli KR, de Benedicdtis M, et al. Coronary angioplasty in an Italian hospital without on-site cardiac surgery: the results and outlook [in Italian]. G Ital Cardiol 1994;24:1529-1536.19. Reifart N, Preusler W, Schwarz F, et al. A large center experience of coronary angioplasty without on-site surgical standby. In: Topol EJ, Serruys PW, ed. Current Review of Interventional Cardiology, 2nd ed. Current Medicine, Philadelphia, 1995, pp. 296-303.20. Dellavalle A, Steffenino G, Ribichini F, et al. Elective coronary angioplasty with and without surgical standby: clinical and angiography for the selection of patients. Coronary Artery Disease 1995;6:513-520.21. Vogt A, Bonzel T, Harmjanz D. PTCA registry of German community hospitals. Eur Ht J 1997;18:1110-1114.22. Shaw TRD, Starkey IR, Essop AR, et al. Emergency coronary bypass surgery after vessel occlusion at angioplasty in centres without on-site facilities for cardiac surgery [abstract]. Br Heart J 1989;61:438.23. Shaw TRD. Does angioplasty need on site surgical cover? A physician’s view. Br Heart J 1990;64:3-4.24. Richardson SG, Morton P, Murtagh JG, et al. Management of acute coronary occlusion during percutaneous transluminal coronary angioplasty: experience of complications in a hospital without on site facilities for cardiac surgery. Br Med J 1990:30:355-358.25. Cannon C, et al. Treat angina with aggrastat and determine cost of therapy with an invasive or conservative strategy (TACTICS TIMI 18). Presented at the 73rd Scientific Sessions of the American Heart Association, New Orleans, LA, November 15, 2000.26. Ribichini F, Uslenghi E, Picco L, et al. Elective coronary angioplasty in total absence of heart surgery. G Ital Cardiol 1994;24:949-956.27. Foot DK, Lewis RP, Pearson TA, Beller GA. Demographics and cardiology, 1950-2050. J Am Col Cardiol 2000;35:66B-80B.28. Jacobs, A. ACC/AHA PTCA guidelines discussion, ACC Scientific Session 2000; March 15, 2000.29. Haraphongse M, Kunjara Na-Ayudhaya R, Burton J, et al. Clinical efficacy of emergency bypass surgery for failed coronary angioplasty. Can J Cardiol 1990;6:186-190.30. Richardson SG, Morton P, Murtagh JG, et al. Management of acute coronary occlusion during percutaneous transluminal coronary angioplasty: experience of complications in a hospital without on site facilities for cardiac surgery. Br Med J 1990;300:355-358.31. Carey JA, Davies SW, Balcon R, et al. Emergency surgical revascularization for coronary angioplasty complications. Br Heart J 1994;72:428-435.32. Kereiakes DJ, Smith SC, Jacobs AK, Kern MJ, Faxon DP. Angioplasty for acute myocardial infarction in community hospital without surgical back-up: response to Wharton and Angelini publications "Should guidelines be changed?: Not whether but when" [letter]. J Am Coll Cardiol 2000;36:299–300.33. Canto JG, Every NR, Magid DJ, et al. The volume of primary angioplasty procedures and survival after acute myocardial infarction. N Engl J Med 2000;342:1573-1580.34. Cannon CP, Gibson CM, Lambrew CT, et al. Relationship of symptom-onset-to-balloon time and door-to-balloon time with mortality in patient undergoing angioplasty for acute myocardial infarction. JAMA 2000;283:2941-2947.35. Every NR, Maynard C, Schulman K, Ritchie JL. The association between institutional primary angioplasty procedure volume and outcome in elderly Americans. J Invasive Cardiol 2000;12:303-308.36. Hirshfield JW Jr, Ellis SG, Faxon DP, et al. Recommendations for the assessment and maintenance of proficiency in coronary interventional procedures: statement of the American College of Cardiology. J Am Coll Cardiol 1998;31:722-743.37. Hannan EL, Racz M, Ryan TJ, et al. Coronary angioplasty volume-outcome relationships for hospitals and cardiologists. JAMA 1997;892-898.38. Kimmel SE, Berlin JA, Laskey WK. The relationship between coronary angioplasty procedure volume and major complications. JAMA 1995;274:1137-1142.39. Kato NS, Carter GM. Volume-mortality tradeoff for percutaneous transluminal coronary angioplasty in the United States [abstract]. J Am Coll Cardiol 1996;27:13A40. Jollis JG, Peterson ED, Nelson CL, et al. Relationship between physician and hospital coronary volume and outcome in elderly patients. Circulation 1997;95:2485-2491.41. Grassman ED, Johnson SA, Krone RJ. Predictors of success and major complications for primary percutaneous transluminal coronary angioplasty in acute myocardial infarction: an analysis of the 1990 to 1994 Society for Cardiac Angiography and Interventions registries. J Am Coll Cardiol 1997;30:201-208.42. Ritchie JL, Maynard D, Every NR, Chapko MK. Coronary artery stent outcomes in a Medicare population: less emergency bypass surgery and lower mortality rates in patients with stents. Am Heart J 1999;138:437-40.43. Rill V, Brown DL. Practice of coronary angioplasty in California in 1995: comparison to 1989 and impact of coronary stenting. Circulation 1999;99:e12.44. Ho V. Evolution of the volume-outcome relation for hospitals performing coronary angioplasty. Circulation 2000;101:1806-1811.45. Huff ED. Volume of coronary angioplasty procedures and mortality rates [letter]. N Engl J Med 1995;332:1304.46. Doucet M, Eisenberg MJ, Joseph L, Pilote L. The effect of hospital volume on long-term outcome after percutaneous transluminal coronary angioplasty [abstract]. J Am Coll Cardiology 2000;35:12A.47. McGrath PD, Wennberg DE, Dickens JD, et al. Relation between operator and hospital volume and outcomes following percutaneous coronary interventions in the era of the coronary stent. JAMA 2000;284:3139-3144.48. Jollis JG, Romano PS. Volume-outcome relationship in acute myocardial infarction: the balloon and the needle. JAMA 2000;284:3169-3171.49. Wharton TP Jr, McNamara NS, Friedman S, et al. Non-Emergent Coronary Intervention Without Cardiac Surgery On Site: Outcomes in 1,501 Patients in the US [abstract]. Circulation 2000;102:II-731-2.50. Meier B. Surgical standby for percutaneous transluminal coronary angioplasty. In: Topol, EJ, ed. Textbook of Interventional Cardiology, 3rd Edition. Philadelphia PA: W.B. Saunders Company, 1999:466-474.51. Shubrooks SJ Jr; Malenka DJ; Piper WD, et al. Safety and efficacy of percutaneous coronary interventions performed immediately after diagnostic catheterization in northern New England and comparison with similar procedures performed later. Am J Cardiol 2000;86:41-45.52. Vogel JHK, King SB III, The Practice of Interventional Cardiology 2nd Edition. St. Louis MO: Mosby--Year Book, Inc., 1993:423