Abstract
Background: Patients with coronary artery disease are managed differently in different countries.
Hypothesis: These variations in patient management may affect clinical outcome, a possibility that should be taken into consideration in multicenter studies.
Methods: In a binational, 3 months study of antithrombotic treatment of patients with unstable angina and non‐Q‐wave infarction (ATACS), we compared the experience in the four enrollment centers in the United States (US) with the three centers in the United Kingdom (UK). The 59 US patients and the 299 UK patients were similar with regard to age, rates of prior revascularization, prior positive exercise tests, medication use, and aspirin use.
Results: US patients were more commonly women (45 vs. 28%), diabetic (30 vs. 4%), or hypertensive (52 vs. 31%), and had a prior coronary angiogram (30 vs. 18%). After enrollment, coronary angiography was performed more frequently in the US than in the UK (61 vs. 22%). Although the distribution of coronary disease was similar, revascularization without recurrent angina (19 vs. 4%, p<0.001), or following recurrent angina (8 vs. 3%), was significantly more frequent in the US. Combined primary end points (recurrent angina, myocardial infarction, or death) did not differ between US (29%) and UK (25%) patients.
Conclusion: Therefore, international studies of acute coronary disease need to account for different treatments in different countries. These differences, in the small ATACS study, did not have a major impact on the composite primary outcome variables.
Keywords: unstable angina, United States, United Kingdom
Full Text
The Full Text of this article is available as a PDF (479.9 KB).
References
- 1. Brook RH, Kosecoff JB, Park RE, Chassin MR, Winslow CM, Hampton JR: Diagnosis and treatment of coronary artery disease: Comparison of doctors' attitudes in the USA and the UK. Lancet 1988; 1: 750–753 [DOI] [PubMed] [Google Scholar]
- 2. Van de Werf F, Topol EJ, Lee KL, Woodlief LH, Granger CB, Armstrong PW, Barbash GI, Hampton JR, Guerci A, Simes RJ, Ross AM, Califf RM, for the GUSTO Investigators : Variations in patient management and outcomes for acute myocardial infarction in the United States and other countries. J Am Med Assoc 1995; 273: 1586–1591 [DOI] [PubMed] [Google Scholar]
- 3. Cohen M, Adams PC, Parry G, Xiong J, Chamberlain D, Wieczorek I, Fox KAA, Chesebro JH, Strain J, Keller C, Kelly A, Lancaster G, Ali J, Kronmal R, Fuster V, and the Antithrombotic Therapy in Acute Coronary Syndromes Research Group : Combination anti‐thrombotic therapy in unstable rest angina and non‐Q wave infarction in nonprior aspirin users: Primary end points analysis from the ATACS trial. Circulation 1994; 89: 81–88 [DOI] [PubMed] [Google Scholar]
- 4. Cohen M, Parry G, Adams PC, Xiong J, Chamberlain D, Wieczorek I, Fox KAA, Keller C, Kronmal R, Fuster V, and the Anti‐thrombotic Therapy in Acute Coronary Syndromes Research Group : Prospective evaluation of a prostacyclin sparing aspirin formulation and heparin/warfarin in aspirin users with rest unstable angina or non‐Q wave myocardial infarction. Eur Heart J 1994; 15: 1196–1203 [DOI] [PubMed] [Google Scholar]
- 5. Luchi R, Scott SM, Deupree RH, and the principal investigators and their associates of Veterans Administration Cooperative Study No. 28: Comparison of medical and surgical treatment for unstable angina pectoris. N Engl J Med 1987; 316: 977–984 [DOI] [PubMed] [Google Scholar]
- 6. The TIMI IIIB Investigators : Effects of tissue plasminogen activator and a comparison of early invasive and conservative strategies in unstable angina and non‐Q wave myocardial infarction. Results of the TIMI IIIB trial. Circulation 1994; 89: 1545–1556 [DOI] [PubMed] [Google Scholar]
- 7. Naylor CD, Sykora K, Jaglal SB, Jefferson S, and the Steering Committee of the Adult Cardiac Care : Waiting for coronary artery bypass surgery: Population‐based study of 8,517 consecutive patients in Ontario, Canada. Lancet 1995; 346: 1605–1609 [DOI] [PubMed] [Google Scholar]
- 8. Rouleau JL, Moye LA, Pfeffer MA, Arnold JMO, Bernstein V, Cuddy TE, Dagenais GR, Geltman EM, Goldman S, Gordon D, Hamm HP, Klein M, Lamas GA, McCans J, McEwan P, Menapace FJ, Parker JO, Sestier F, Sussex B, Braunwald E, for the SAVE Investigators : A comparison of management patterns after acute myocardial infarction in Canada and the United States. N Engl J Med 1993; 328: 779–784 [DOI] [PubMed] [Google Scholar]
- 9. Lotan CS, Jonas M, Rozenman Y, Mosseri M, Benhorin J, Rudnik L, Hasin Y, Gotsman MS: Comparison of early invasive and conservative treatments in patients with anterior wall non‐Q wave acute myocardial infarction. Am J Cardiol 1995; 76: 330–336 [DOI] [PubMed] [Google Scholar]
- 10. Every NR, Larson EB, Litwin PE, Maynard C, Fihn SD, Eisenberg MS, Hallstrom AP, Martin JS, Weaver WD, for the Myocardial Infarction Triage and Intervention Project Investigators : The association between on‐site cardiac catheterization facilities and the use of coronary angiography after acute myocardial infarction. N Engl J Med 1993; 329: 546–551 [DOI] [PubMed] [Google Scholar]
- 11. Pilote L, Califf RM, Sapp S, Miller DP, Mark DB, Weaver WD, Gore JM, Armstrong PW, Ohman EM, Topol EJ, for the GUSTO‐1 Investigators : Regional variation across the United States in the management of acute myocardial infarction. N Engl J Med 1995; 333: 565–572 [DOI] [PubMed] [Google Scholar]
- 12. Guadagnoli E, Hauptman PJ, Ayanian JZ, Pashos CL, McNeil BJ, Cleary PD: Variation in the use of cardiac procedures after acute myocardial infarction. N Engl J Med 1995; 333: 573–578 [DOI] [PubMed] [Google Scholar]
- 13. The RISC Group : Risk of myocardial infarction and death during treatment with low dose aspirin and intravenous heparin in men with unstable coronary artery disease. Lancet 1990; 336: 827–830 [PubMed] [Google Scholar]
- 14. Wallentin LC and The research group on instability in coronary artery disease in South East Sweden : Aspirin (75mg/day) after an episode of unstable coronary artery disease: Long‐term effects on the risk for myocardial infarction, occurrence of severe angina and the need for revascularization. J Am Coll Cardiol 1991; 18: 1587–1593 [DOI] [PubMed] [Google Scholar]