Opinion Statement
The recent availability of novel antiplatelet and antithrombin agents has revolutionized the therapeutic options for intermediate- and high-risk unstable angina (UA). Current guidelines recommend aspirin, unfractionated heparin (UFH), and antianginal therapy. Low-molecular-weight heparin (LMWH) and direct thrombin inhibitors have significant theoretical advantages and apparent clinical benefits compared with UFH and are good alternatives in selected patients. Glycoprotein (GP) IIb/IIIa receptor inhibition reduces the future risk of myocardial infarction (MI) and may reduce the incidence of death in patients with unstable angina. In particular, these drugs should be considered for use in combination with aspirin and UFH in patients undergoing an “early invasive” approach. Coronary revascularization plays an important role in high-risk patients and in those with refractory angina, but its routine application continues to be controversial. Issues regarding the use of LMWH in combination with GP IIb/IIIa inhibitors and during percutaneous transluminal coronary angioplasty (PTCA) are being addressed in clinical trials. Ideally, the incidence of serious cardiac events in patients with UA will continue to decrease with the ongoing search for potent drug combinations that achieve early control of intracoronary thrombosis.
Similar content being viewed by others
References and Recommended Reading
Fulton M, Lutz W, Donald KW, et al.: Natural history of unstable angina. Lancet 1972, 1:860–865.
Domburg RT, Miltenburg-van Zijl AJ, Veerhoek RJ, et al.: Unstable angina: good long-term outcome after a complicated early course. J Am Coll Cardiol 1998, 31:1534–1539.
The PRISM Study Investigators: A comparison of aspirin plus tirofiban with aspirin plus heparin for unstable angina. N Engl J Med 1998, 338:1498–1505.
The GUSTO IIb Investigators: A comparison of recombinant hirudin with heparin for the treatment of acute coronary syndromes. N Engl J Med 1996, 335:775–782.
Braunwald E, Jones RH, Mark DB, et al.: Diagnosing and managing unstable angina. AHCPR guidelines for unstable angina. Circulation 1994, 90:613–622. Essential reading to understand the rationale behind clinical practice.
Kong DF, Califf RM, Miller DP, et al.: Clinical outcomes of therapeutic agents that block the platelet glycoprotein IIb/IIIa integrin in ischemic heart disease. Circulation 1998, 98:2829–2835. Review of all interventional and acute coronary syndrome trials that evaluate the efficacy of treatment with glycoprotein IIb/IIIa inhibitors.
Patel V, Topol E: The pathogenesis and spectrum of acute coronary syndromes: from plaque formation to thrombosis. Cleve Clin J Med 1999, 66(9):561–571.
Depre C, Wijns W, Robert AM, et al.: Pathology of unstable plaque: correlation with clinical severity of acute coronary syndromes. J Am Coll Cardiol 1997, 30:694–702.
Theroux R, Fuster V: Acute coronary syndromes: unstable angina and non-Q wave MI. Circulation 1998, 97:1195–1206. An outstanding, updated, comprehensive review addressing the spectrum of disease, established and potential pathophysiologic concepts, risk stratification, and management issues.
Braunwald E. Unstable angina: a classification. Circulation 1989, 80(2):410–414.
Aguirre FV, Younis LL, Chaitman BR, et al.: Early and 1 year clinical outcome of patients evolving non-Q wave versus Q-wave MI after thrombolysis: results from the TIMI II study. Circulation 1995, 91:2541–2548.
Zareba W, Moss AJ, Raubertas RF, et al.: Risk of subsequent cardiac events in stable convalescing patients after first non-Q wave and Q-wave MI. Coron Artery Dis 1994, 5:1009–1018.
Antman EM, Tanasijevic MJ, Thompson B, et al.: Cardiac-specific troponin I levels to predict the risk of mortality in patients with acute coronary syndromes. N Engl J Med 1996, 335:1342–1349.
Ohman EM, Armstrong PW, Christenson RH, et al.: Cardiac troponin T levels for risk stratification in acute myocardial ischemia. N Engl J Med 1996, 335:1333–1341.
Moreno R, Lopez de Sa E, Lopez-Sendon JL, et al.: Prognosis of medically stabilized unstable angina with a negative exercise test. Am J Cardiol 1998, 82:662–665.
Cannon CP, McCabe CH, Stone PH, et al.: The electrocardiogram predicts one-year outcome of patients with unstable angina and non-Q wave MI: results of the TIMI III registry ECG ancillary study. J Am Coll Cardiol 1997, 30:133–140.
Betriu A, Heras M, Cohen M, et al.: Unstable angina: outcome according to clinical presentation. J Am Coll Cardiol 1992, 19:1659–1663.
Lincoff AM, Califf RM, Anderson KM, et al.: Evidence for prevention of death and MI with platelet membrane GP IIb/IIIa receptor blockade by abciximab (c7E3 Fab) among patients with unstable angina undergoing percutaneous coronary revascularization. J Am Coll Cardiol 1997, 30:149–156.
The CAPTURE Investigators: Randomized placebocontrolled trial of abciximab before and during coronary intervention in refractory unstable angina: the CAPTURE study. Lancet 1997, 349:1429–1435.
Shepherd J, Cobbe SM, Ford I, et al.: Prevention of coronary heart disease with pravastatin in men with hypercholesterolemia. West of Scotland Coronary Prevention Study Group. N Engl J Med 1995, 333:1301–1307.
The Scandinavian Simvastatin Survival Study: Randomized trial of cholesterol lowering in 4444 patients with coronary heart disease: the Scandinavian Simvastatin Survival Study (4S). Lancet 1994, 344:1383–1389.
The Long-Term Intervention with Pravastatin in Ischaemic Disease (LIPID) Study Group: Prevention of cardiovascular events and death with pravastatin in patients with coronary heart disease and a broad base of initial cholesterol levels. N Engl J Med 1998, 339:1349–1357.
The Sixth Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure. Arch Intern Med 1997, 157(21):2413-2446.
Antiplatelet Trialists’ Collaboration: Collaborative review of randomized trials of anti-platelet therapy. I. Prevention of death, MI, and stroke by prolonged anti-platelet therapy in various categories of patients. BMJ 1994, 308:81–106.
Theroux R, Ouimet H, McCans J, et al.: Aspirin, heparin or both to treat acute unstable angina. N Engl J Med 1988, 319(17):1105–1111.
The RISC Group: Risk of MI and death during treatment with low dose aspirin and intravenous heparin in men with unstable coronary artery disease. Lancet 1990, 336:827–830.
Lewis HD, Davis JW, Archibald DG, et al.: Protective effects of aspirin against MI and death in men with unstable angina. N Engl J Med 1983, 309:396–403.
Cairns JA, Gent M, Singer J, et al.: Aspirin, sulfinpyrazone or both in unstable angina. N Engl J Med 1985, 313:1369–1375.
Balsano F, Rizzon P, Violi F, et al. for the Studio della Ticlopidina nell’Angina Instabile Group: Antiplatelet treatment with ticlopidine in unstable angina: a controlled multi-center clinical trial. Circulation 1990, 82:17–26.
CAPRIE Steering Committee: A randomized, blinded, trial of clopidogrel versus aspirin in patients at risk of ischemic events (CAPRIE). Lancet 1996, 348(9038):1329–1339.
The PRISM-PLUS Study Investigators: Inhibition of the platelet GP IIb/IIIa receptor with tirofiban in unstable angina and non-Q wave MI. The platelet receptor inhibition in ischemic syndrome in patients limited by unstable signs and symptoms. N Engl J Med 1998, 338:1488–1497.
The PURSUIT Trial Investigators: Inhibition of platelet GP IIb/IIIa with eptifibatide in patients with acute coronary syndromes. N Engl J Med 1998, 339:436–443.
The PARAGON Investigators: International, randomized, controlled trial of lamifiban, heparin, or both in unstable angina. Circulation 1998, 97:2386–2395.
Topol EJ, Ferguson JJ, Weismann HF, et al.: Long term protection from myocardial ischemic events after brief integrin b1 blockade with percutaneous coronary intervention. JAMA 1997, 278:479–484.
Mark DB, Talley D, Topol EJ, et al.: Economic assessment of platelet GP IIb/IIIa inhibition for prevention of ischemic complications of high-risk coronary angioplasty. Circulation 1996, 94:629–635.
Xiao Z, Theroux P: Platelet activation with UFH at therapeutic concentrations and comparisons with a low-molecular-weight heparin and with a direct thrombin inhibitor. Circulation 1998, 97:251–256.
Theroux P, Waters D, Lam J, et al.: Reactivation of unstable angina after the discontinuation of heparin. N Engl J Med 1992, 327(3):141–145.
Telford AM, Wilson C: Trial of heparin versus atenolol in prevention of MI in intermediate coronary syndrome. Lancet 1981, 1:1225–1228.
Holdright D, Patel D, Cunningham D, et al.: Comparison of the effect of heparin and aspirin versus aspirin alone on transient myocardial ischemia and in-hospital prognosis in patients with unstable angina. J Am Coll Cardiol 1994, 24:39–45.
Theroux P, Waters D, Qui S, et al.: Aspirin versus heparin to prevent MI during the acute phase of unstable angina. Circulation 1993, 88(part 1):2045–2048.
Gurfinkel EP, Manos EJ, Mejail RI, et al.: Low molecular weight heparin versus regular heparin or aspirin in the treatment of unstable angina and silent ischemia. J Am Coll Cardiol 1995, 26:313–318.
Fragmin during Instability in Coronary Artery Disease (FRISC) Study Group: Low-molecular weight heparin during instability in coronary artery disease. Lancet 1996, 347:561–568.
Klein W, Buchwald A, Hillis SE, et al.: Comparison of low-molecular-weight heparin with unfractionated heparin acutely and with placebo for 6 weeks in the management of unstable coronary artery disease: Fragmin in Unstable Coronary Artery Disease Study (FRIC). Circulation 1997, 96:61–68.
Cohen M, Demers C, Gurfinkel EP, et al. for the ESSENCE Study Group: A comparison of lowmolecular weight heparin with unfractionated heparin for unstable coronary artery disease. N Engl J Med 1997, 337:447–452.
Antman EM, McCabe CH, Gurfinkel EP, et al.: Enoxaparin prevents death and cardiac ischemic events in unstable angina/non-Q-wave myocardial infarction. Results of the thrombolysis in myocardial infarction (TIMI) 11b trial. Circulation 1999, 100:1593–1601.
Mark DB, Cowper PA, Berkowitz SD, et al.: Economic assessment of low-molecular-weight-heparin (enoxaparin) versus unfractionated heparin in acute coronary syndrome patients: results from the ESSENCE randomized trial. Circulation 1998, 97(17):1702–1707.
Topol EJ, Fuster V, Harrington RA, et al.: Recombinant hirudin for unstable angina pectoris. A multicenter, randomized angiographic trial. Circulation 1994, 89:1557–1566.
The GUSTO IIb Investigators: A comparison of recombinant hirudin with heparin for the treatment of acute coronary syndromes. N Engl J Med 1996, 335:775–782.
Fuchs J, Cannon CP, and the TIMI 7 Investigators: Hirulog in the treatment of unstable angina. Results of the Thrombin Inhibition in Myocardial Ischemia (TIMI) 7 trial. Circulation 1995, 92:727–733.
OASIS-2 Investigators: Effects of recombinant hirudin (lepirudin) compared with heparin on death, MI, refractory angina, and revascularization procedures in patients with acute myocardial ischemia without ST elevation: a randomized trial. Lancet 1999, 353:429–438.
Weihrauch T, Baumann J, Ebner F: Early treatment of unstable angina in the coronary care unit: a randomised, double blind, placebo controlled comparison of recurrent ischaemia in patients treated with nifedipine or metoprolol or both. Br Heart J 1988, 59:270–272.
Theroux P, Taeymans Y, Morissette D, et al.: A randomized study comparing propranolol and diltiazem in the treatment of unstable angina. J Am Coll Cardiol 1985, 5:717–722.
Smith NL, Reiber GE, Psaty BM, et al.: Health outcomes associated with beta-blocker and diltiazem treatment of unstable angina. J Am Coll Cardiol 1998, 32:1305–1311.
Yusuf S, Wittes J, Friedman L: Overview of results of randomized clinical trials in heart disease II: unstable angina, heart failure, primary prevention with aspirin, and risk factor modification. JAMA 1988, 260(15):2259–2263.
Gottlieb SS, McCarter RJ, Vogel RA, et al.: Effect of beta-blockade on mortality among high-risk and low-risk patients after myocardial infarction. N Engl J Med 1998, 339:489–497.
Anderson HV, Cannon CP, Stone PH, et al.: One-year results of the TIMI IIIb clinical trial. J Am Coll Cardiol 1995, 26:1643–1650.
Boden WE, O’Rourke RA, Crawford MH, et al.: Outcomes in patients with acute non-Q wave myocardial infarction randomly assigned to an invasive as compared with a conservative management strategy. N Engl J Med 1998, 338:1785–1792.
Cannon CP, Weintraub WS, Demopoulos LA, et al.: Invasive versus conservative strategies in unstable angina and non-Q wave MI following treatment with tirofiban: rationale and study design of the international TACTICS-TIMI 18 trial. Am J Cardiol 1998, 82:731–736.
Fragmin and Fast Revascularisation during InStability in Coronary artery disease Investigators: Invasive compared with non-invasive treatment in unstable coronary-artery disease. FRISC II prospective randomised multicentre study. Lancet 1999, 354:708–715.
Serruys P, van Hout B, Bonnier H, et al.: Randomised comparison of implantation of heparin-coated stents with balloon angioplasty in selected patients with coronary artery disease. Lancet 1998, 352:673–681.
Parisi AF, Khuri S, Deupree RH, et al.: Medical compared with surgical management of unstable angina: 5 year mortality and morbidity in the Veterans Administration group. Circulation 1989, 80:1176–1189.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Murad, M.B., Henry, T.D. Unstable angina. Curr Treat Options Cardio Med 2, 37–53 (2000). https://doi.org/10.1007/s11936-000-0027-9
Issue Date:
DOI: https://doi.org/10.1007/s11936-000-0027-9