Chronic stable angina treatment aspirin

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [mailto:mgibson@perfuse.org] Phone:617-632-7753; Associate Editor(s)-In-Chief: ; John Fani Srour, M.D.; Jinhui Wu, M.D.; Lakshmi Gopalakrishnan. M.B.B.S.

Overview
In patients with ischemic heart disease, prophylactic low dose aspirin prevents arterial thrombosis by irreversible inactivation of platelet aggregation.

Mechanisms of benefit

 * Aspirin is a potent anti-platelet agent.


 * Aspirin induces an irreversible functional defect in platelets by inhibiting cyclo oxygenase (COX-1) and subsequently suppressing the activation of thromboxane A2 that is responsible for platelet aggregation.


 * In patients with chronic stable angina, prior MI and unstable angina, aspirin improves survival and prevents infarction.


 * Aspirin has shown to improve endothelial function and at high doses reduce acute phase reactants.

Indication
All patients with chronic stable angina, aspirin unless contraindicated should be started at 75 to 162 mg/day and continued indefinitely.

Contra-indications

 * Gastrointestinal bleed
 * Aspirin hypersensitivity (triad of rhinitis, asthma and polyposis)
 * Coagulation disorder
 * Uncontrolled hypertension

Dosage

 * A dose range of 75 to 162 mg/day of aspirin appears to be effective and is associated with lower risk of gastrointestinal bleeding.


 * In comparison to a dose range of 160-325 mg/day, a lower dose of aspirin (75-162mg/d) has a higher efficacy for secondary prevention.


 * Aspirin improves endothelial function and at higher doses (300 mg/day) reduce the circulating levels of C-reactive protein.

Drug interactions
Use of warfarin in conjunction with aspirin and/or clopidogrel is associated with an increased risk of bleeding and therefore, close monitoring is required.

Adverse effects
A higher dose of aspirin is associated with increased risk of gastrointestinal bleed.

Supportive trial data

 * Meta-analysis (2002) of 140,000 patients from the Antiplatelet Trialists’ Collaboration showed that aspirin (75-325 mg/day) reduced the rate of subsequent myocardial infarction, stroke, and death in patients with history of angina pectoris, myocardial infarction, CABG, and stroke.


 * Meta-analysis(2000) of 24 randomized controlled trials involving 66,000 patients showed significant increase in the incidence of gastrointestinal hemorrhage associated with long term aspirin therapy. There was no supportive evidence of lower dose or modified release formulations reducing the incidence of GI bleed.


 * In the Swedish Angina Pectoris Aspirin Trial (SAPAT) (1992), aspirin (75 mg/day) in conjunction with the beta blocker sotalol conferred an additional 34% reduction in acute myocardial infarction and sudden cardiac death among men and women with chronic stable angina.

==ACC/AHA Guidelines- Pharmacotherapy to Prevent MI and Death and Reduce Symptoms (DO NOT EDIT)  == {{cquote|

Class I
1. Aspirin should be started at 75 to 162 mg per day and continued indefinitely in all patients unless contraindicated. (Level of Evidence: A)

2. Aspirin in the absence of contraindication in patients with prior MI. (Level of Evidence: A)

3. Use of warfarin in conjunction with aspirin and/or clopidogrel is associated with an increased risk of bleeding and should be monitored closely. (Level of Evidence: B)

Class IIa
1. Clopidogrel when aspirin is absolutely contraindicated. (Level of Evidence: B)}}

==ESC Guidelines- Pharmacological therapy to improve prognosis in patients with stable angina (DO NOT EDIT) == {{cquote|

Class I
1. Aspirin 75 mg daily in all patients without speciﬁc contraindications (i.e. active GI bleeding, aspirin allergy, or previous aspirin intolerance). (Level of Evidence: A)}}

Vote on and Suggest Revisions to the Current Guidelines

 * The Chronic Stable Angina Living Guidelines: Vote on current recommendations and suggest revisions to the guidelines

Guidelines Resources

 * The ACC/AHA/ACP–ASIM Guidelines for the Management of Patients With Chronic Stable Angina


 * The ACC/AHA 2002 Guideline Update for the Management of Patients With Chronic Stable Angina


 * The 2007 Chronic Angina Focused Update of the ACC/AHA 2002 Guidelines for the Management of Patients With Chronic Stable Angina


 * Guidelines on the management of stable angina pectoris: The Task Force on the Management of Stable Angina Pectoris of the European Society of Cardiology