By Hannah Woolley
In a multivariate analysis including both BRUISE CONTROL 1 and BRUISE CONTROL 2 patients and adjusted for antiplatelet use, there was no difference in clinically significant haematoma between direct oral anticoagulants (DOACs) and warfarin.
Oral anticoagulant use is common among patients requiring pacemakers or defibrillator surgery. The Bridge or Continue Coumadin for Device Surgery Randomised Controlled (BRUISE CONTROL) trial demonstrated 80% fewer device pocket haematomas when surgery was performed without interruption of warfarin, compared to warfarin treated patients who had their anticoagulation interrupted and received heparin bridging but since the publication of the first BRUISE CONTROL trial the use of DOACs has drastically increased and they are now used in the majority of patients with atrial fibrillation. This led to the Strategy of Continued Versus Interrupted Novel Oral Anti-coagulant at Time of Device Surgery in Patients With Moderate to High Risk of Arterial Thromboembolic Events (BRUISECONTROL 2) trial.
BRUISECONTROL 2 showed that the rates of clinically significant haematoma were the same in both continued and interrupted DOAC groups.
Device pocket haematomas have a significant impact on patients as it may be necessary to stop anticoagulation for a prolonged period of time, increasing the risk of thromboembolism and serious device system infection.
Both trials were multicentre single blinded randomised control trials. To be eligible for the BRUISE CONTROL 1 trial patients had to have a ≥5% annual predicted risk of thromboembolisms, be taking warfarin and be undergoing non-emergency device related surgery. During treatment the continued-warfarin arm had a targeted INR of 3 or less, except for patients with mechanical valves, their target INR was 3.5 or less. Patients in the heparin-bridge arm discontinued warfarin five days prior to procedure and started therapeutic heparin three days before the procedure. Heparin was restarted 24 hours post procedure and continued until a therapeutic INR was reached.
BRUISE CONTROL 2 patients were treated with dabigatran, rivaroxaban or apixaban and had a CHA2DS2-VASc score of ≥2. They were randomised to continued or interrupted DOAC.
Patients in the continuous DOAC arm had their DOAC continued throughout the surgical period and took their morning dose prior to surgery. Those in the interrupted DOAC arm on rivaroxaban or apixaban had their drug discontinued after taking their last dose two days before surgery. Patients on dabigatran discontinued the drug at a time interval dependent on their glomerular filtration rate. All three drugs were resumed at the next regular dose timing after 24 hours post-surgery.
In both studies the primary outcome was clinically significant haematoma, requiring surgery, resulting in prolonged hospitalisation or requiring interruption of anticoagulation for more than 24 hours.
To carry out the analysis the investigators were blinded. Each centre was required to identify two patient care teams. The unblinded team, had knowledge of treatment allocation and was responsible for device implantation and the blinded team, had no knowledge of treatment allocation and was responsible for diagnosing, following and making decision on haematomas.
The results show almost a doubling of clinically significant haematoma in the single/dual antiplatelet group compared to no antiplatelet. The multivariable analysis looked at the predictors of haematoma. When bridging with heparin, compared to continued warfarin there was a six-fold increase in the rate of haematoma and there was no significant difference with DOAC use compared to continuous warfarin. The study also found that those with diabetes had a lower rate of haematoma, which the investigators say is worth of further exploration. Significantly, they found that antiplatelet use doubled the rate of haematoma.