Research News

Uninterrupted anticoagulation during pacemaker or defibrillator surgery

BMJ 2013; 346 doi: (Published 15 May 2013) Cite this as: BMJ 2013;346:f3087

The management of anticoagulation during surgery for a pacemaker or implantable cardioverter defibrillator involves balancing the risk of bleeding against the risk of thromboembolism. Guidelines currently recommend switching from warfarin to more flexible heparins around the time of the procedure, but a trial from Canada suggests that continuing with warfarin might be safer. Haematomas of the device pocket were a significantly bigger problem for adults who switched to heparins than for those who continued their regular warfarin treatment (16% (54/338) v 3.5% (12/343); P<0.001). The result was so convincing that a data monitoring board stopped the trial early.

Most of those who switched started treatment with low molecular weight heparin three days before the procedure. They had no injections for 24 hours before or after the procedure. International normalised ratios (INRs) were lower on the day of surgery in this group (mean 1.2 v 2.3). Why did they have more haematomas? Possibly because bleeding points are obvious at the time of surgery in people taking warfarin and can be dealt with while the wound is open. Bleeding may occur only later, when heparin is restarted, in patients who switch, say the authors.

Two participants had thromboembolic events (one stroke, one transient ischaemic attack). Both were older women at high risk who continued warfarin treatment. Both had suboptimal anticoagulation at the time of the procedure (INRs 1.0 and 1.2).


Cite this as: BMJ 2013;346:f3087

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