HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Alert me to new issues of the journal Add to Personal Folders Download to citation manager Author home page(s): Joel Dunning Permission Requests Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Dunning, J. Search for Related Content PubMed Articles by Dunning, J. Related Collections Cardiac - pharmacology Coronary disease Valve disease

Letters to the Editor

Reply to Colli and Mestres. Controversial issues regarding aspirin and clopidogrel therapy for patients after cardiac surgery

Department of Cardiothoracic Surgery, James Cook University Hospital, Middlesbrough, UK

Received 30 September 2008; accepted 2 October 2008.

^_* Corresponding author. Tel.: +44 7801548122; fax: +44 7801548122. (Email: joeldunning{at}doctors.org.uk).

Key Words: Guideline • Antiplatelet • Anticoagulation

I thank Dr Colli for his comments [1] and also for all his hard work over the last few years with the ACTION registry [2] looking to resolve important issues over anticoagulation after bioprosthetic aortic valve replacement.

Guidelines are an ever-moving field and the AHA/ACC, ACCP and ERC all provide an outstanding service in regularly updating their guidelines. The EACTS guideline on antiplatelet and anticoagulation management, accepted for publication in February 2008 and published in July 2008 are the second in the series of EACTS guidelines. In the future we will also aim to update these guidelines on a regular basis taking into account the results of fully published papers as they become available and also of subsequent guidelines published after our first version such as those by the ACCP [3].

We agree with your first point that aspirin is recommended at a low dose by the ACC and AHA in addition to warfarin, and that the ACCP are more careful with their recommendation. Our recommendation for aspirin in addition to warfarin was based on our literature review of the 11 original trials performed in this area together with consideration of these trials by 12 meta-analyses or other guidelines [4]. We caution that this policy would increase the incidence of bleeding complications but reduce thromboembolic events with a number needed to treat of 19.

Our systematic review of the dosage of aspirin after coronary artery surgery was also summarised and published in the ICVTS prior to our recommendation and we discussed in some detail the difficulties in the literature and also the controversy regarding the dosage of aspirin in these large trials, which are now in some cases almost 20 years old. While some guideline agencies recommend lower doses, many others recommend higher doses. In particular the high quality meta-analysis by Lim et al. [5] published in the British Medical Journal in 2003 using novel analytical techniques actually recommended a dose of 300–325 mg. Thus together with the lack of evidence that 150 mg of aspirin causes a higher incidence of gastrointestinal complications compared to 75 mg and also with second level evidence of aspirin resistance in some patients that we considered, but did not include in the final review, we concluded that 150 mg would be our final minimum dosage.

With regard to recommending clopidogrel for postoperative cardiac surgical patients, we again fully reviewed the evidence and published this in the ICVTS in two papers prior to publication of the guideline. We summarised the evidence from 11 papers and guidelines, and we in fact referenced and endorsed the 2004 ACCP recommendation that states that ‘clopidogrel should be started in addition to aspirin and continued for 9–12 months after CABG for non-ST segment elevation acute coronary syndrome’. This was given a grade 1C recommendation by the ACCP.

Thank you once again for your interest in our guideline process and for your active research in this area to resolve the important unanswered issues of antiplatelet therapy in bioprosthetic valvular heart disease.

References

1. Colli A, Mestres CA. EACTS guideline on antiplatelet and anticoagulation management in cardiac surgery. Eur J Cardiothorac Surg 2009;35:199.[Free Full Text]
2. Colli A, Verhoye J-P, Heijmen R, Thomas Strauch JT, Hyde JAJ, Pagano D, Antunes M, Koertke H, Ohri SK, Bail DHL, Leprince P, Van Straten BHM, Gherli T, on behalf of ACTION Registry Investigators. Antithrombotic therapy after bioprosthetic aortic valve replacement ACTION registry survey results. Eur J Cardiothorac Surg 2008;33(April):531-536.[Abstract/Free Full Text]
3. Hirsh J, Guyatt G, Albers GW, Harrington R, Schünemann HJ. Antithrombotic and thrombolytic therapy: American college of chest physicians evidence-based clinical practice guidelines. Chest 2008(Jun):110S-112S[8th Edition].
4. Nagarajan DV, Lewis PS, Botha P, Dunning J. Is addition of anti-platelet therapy to warfarin beneficial to patients with prosthetic heart valves?. Interact Cardiovasc Thorac Surg 2004;1(3):450-455.
5. Lim E, Ali Z, Ali A, Routledge T, Edmonds L, Altman DG, Large S. Indirect comparison meta-analysis of aspirin therapy after coronary surgery. Br Med J 2003;327:1309-1311.[Abstract/Free Full Text]

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Alert me to new issues of the journal Add to Personal Folders Download to citation manager Author home page(s): Joel Dunning Permission Requests Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Dunning, J. Search for Related Content PubMed Articles by Dunning, J. Related Collections Cardiac - pharmacology Coronary disease Valve disease