[Safety of implantation permanent pacemaker at different times in patients with dual antiplatelet therapy]

To investigate the safety of implantation permanent pacemaker (PM) at different times in patients with dual antiplatelet (DAPT) therapy after implantation of drug-eluting stent (DES).

A total of 105 patients who implanted pacemakers with DAPT therapy (clopidogrel and aspirin) after implantation of DES admitted to our hospital from January 2009 to January 2015 were enrolled in the study. The patients were divided into 3 groups: dual antiplatelet therapy (DAP) group: implanting PM within 3 months after coronary stenting, continuous DAPT during perioperative period; low molecular weight heparin (LMWH) bridging group: implanting PM within 3 to 6 months after coronary stenting, DAPT interruption for 5 days replaced with subcutaneous injection of enoxaparin (1 mg/kg), twice per day, enoxaparin was stopped 12 h before operation; asprin group, implanting PM after coronary stenting 6 months, clopidogrel interruption for 5 days. Oral DAPT was returned 12-24 after operation according to the patients' condition. Peri-operative cardiovascular events and bleedings, infections were observed.

There was no major adverse cardiac event (MACE) and pouch infection were observed among 3 groups in perioperation. The incidence of pocket hemorrhage and errhysis in bridging group was significantly higher than that of DAP group and asprin group (16.7%, 8.0%, 0.0% χ(2)=10.431, P=0.005 and 29.2%, 12.0%, 7.1% χ(2)=6.321, P=0.042 respectively). 3 patients had severe bleeding (12.5%, 3/24) in bridging group; compared with the other 2 groups, there were significant difference (χ(2)=9.161, P=0.010). The incidence of hematoma and hemorrhage of asprin group was lowest.

LMWH bridging therapy significantly increases the risk of pacemaker pocket hematoma and hemorrhage, and the pacemaker implantation may be safer after DES implantation 6 months.