Regarding patients with a lower annual risk of
Regarding patients with a lower annual risk of thromboembolism (<5%), there is no clear evidence for continued warfarin versus discontinuing warfarin. Clearly, a bridging strategy should not be used, given the low risk of thromboembolism and higher risk of device-pocket hematoma with bridging. Current guidelines suggest to stop warfarin treatment 3–4 days before the procedure, to perform the procedure once the INR is <1.8, and resume warfarin 12–24h later [25,34]. However, as suggested in a recent guideline and in keeping with evidence from two recent meta-analyses, continued warfarin use may be considered, especially if the patient has a history of previous transient ischemic attack or embolic stroke .
Management of direct acting oral anticoagulants during pacemaker insertion There are less data available regarding management of DOACs peri-procedurally. The general principle is that PM/ICD implantation is considered a low bleeding risk procedure [10,34]. Because of the predictable waning anticoagulant effects of DOACs, bridging therapy is not required and management involves timing the cessation and re-initiation of the drug based on the predicted clearance, which takes renal function into account [27,43]. A recent Canadian study showed that device implantation performed with DOAC interruption, but without bridging . In patients with normal renal function undergoing a low bleeding risk procedure, the usual practice is to discontinue the DOAC 24h (i.e. last dose 2 days before) prior to the procedure and to reinstate the drug 24–48h after, provided no significant bleeding has occurred [25,34,45] (Fig. 2). A large randomized control trial (BRUISECONTROL2: ClinicalTrials.gov NCT01675076) is underway, in patients undergoing CIED procedures, to test the safety of continuing DOACs—its results are eagerly awaited . The details for each separate DOAC are discussed below. Dabigatran is a twice daily drug with a 5-Iodotubercidin of 14h, if the CrCl is above 50mL/min. Its use should be halted the day before surgery, which translates to missing 2 doses before the day of surgery. This usually results in a 12–25% residual anticoagulant effect at the time of surgery, which is acceptable given the low risk of bleeding [25,27,45]. If the CrCl is between 30 and 50mL/min, signifying moderate renal impairment and a likely half-life of 15–18h, then dabigatran use should be halted 2 days before surgery, i.e., 4 missed doses to give the same residual anticoagulant effect. Dabigatran should not be used in patients with a CrCl of less than 30mL/min. The drug should then be resumed 24h postoperatively [25,34,45,47,48]. An observational study showed that continued dabigatran treatment did not result in increased bleeding; only one episode of minor bleeding occurred and that was in a patient on dual antiplatelet therapy . This finding has been replicated in other studies ; thus, the results of the randomized control trial  are awaited before final recommendations can be made regarding continuation of DOACs. Rivaroxaban is a once daily drug with a half-life of 9h if the CrCl is above 30mL/min. Its use should halted the day before surgery, which translates to missing one dose before the day of surgery and results in a 12–25% residual anticoagulant effect at the time of surgery, which is acceptable given the low risk of bleeding [27,47,48]. Again, rivaroxaban should not be used in patients with a CrCl less than 30mL/min, but if used in patients with a CrCl between 15 and 30mL/min, at least 36h of drug interruption is advised . Use of the drug should then be resumed 24–48h postoperatively [34,45]. Apixaban is similar to rivaroxaban in its mechanism of action and half-life of 9h if CrCl is above 30mL/min [27,45]. Therefore, use of the drug may be halted the day before surgery and resumed 24–48h postoperatively, if renal function is >30mL/min [34,45,47,48]. If apixaban is used in patients with a CrCl between 15 and 30mL/min then at least 36h of drug interruption is advised . Edoxaban is a once daily drug with a half-life of 10–14h if the CrCl is above 30mL/min . However, there is less guidance available regarding edoxaban and the current recommendation is for use of the drug to be halted the day before surgery and resumed 24–48h postoperatively, if renal function is >80mL/min [25,32]. Given the pharmacokinetics of edoxaban, these recommendations will most likely extend to a CrCl of greater than 30, but guidance is currently lacking.