br Risk of bleeding complications
Risk of bleeding complications with dual antiplatelet agents Dual antiplatelet therapy (DAPT) with combined aspirin and clopidogrel has become a standard treatment after percutaneous coronary intervention (PCI). Recent studies have examined the impact of such therapy on the incidence of bleeding complications after CIED surgery. Dreger et al. did not notice an increased risk of clinically relevant hematoma when a drainage system was applied . However, several other studies have demonstrated a consistently higher risk of bleeding complications in these patients. Wiegand et al. reported that the use of DAPT was highly predictive for intraoperative bleeding and pocket hematoma in patients who have undergone ldk378 and defibrillator implantation, while aspirin monotherapy did not appear to have a significant impact on bleeding complications . Tompkins et al. demonstrated that patients on DAPT had a significantly increased bleeding risk as compared with controls (7.2% vs. 1.6%; p=0.004), while bleeding risk was only marginally higher in patients taking aspirin alone (3.9% vs. 1.6%, p=0.078) . Thal et al. noted that more patients with hematoma were on DAPT than warfarin therapy alone, and those with the highest incidence of hematoma (40%) were on DAPT combined with warfarin . Kutinsky et al. reported the incidence of pocket hematoma after CIED surgery: aspirin 4.2%, warfarin 6.9%, warfarin+aspirin 10.3%, clopidogrel11.1%, DAPT 24.2%, and warfarin+DAPT 9.5% . Clopidogrel use was one of the predictors of pocket hematoma, while aspirin monotherapy did not seem to have a significant impact on bleeding complications. In the meta-analysis by Bernard et al., bleeding event rates were 2.2% for no therapy, 2.5% for warfarin held, 2.8% for warfarin continued, 3.9% for single antiplatelet therapy, 9.4% for DAPT and 14.6% for heparin bridging strategy (Fig. 1) .
Empirical approaches to reduce the perioperative bleeding complications We previously reported that chronic kidney disease was an independent risk factor for pocket hematoma after CIED implantation, probably due to a higher bleeding tendency in these patients . A recent report from a prospective, multicenter registry confirmed that HAS-BLED score predicted bleedings during bridging of chronic oral anticoagulation . Such data are not available in patients on continuous warfarin therapy undergoing CIED surgery. There is hope that improvement in patient co-morbidities, by aggressively treating the underlying diseases, will lead to a lower risk of postoperative bleeding complications. It is important to coordinate the timing of elective PCI and device surgery. Elective PCI should be postponed if possible after device surgery to avoid DAPT in the immediate postoperative period. Target vein venography could be used more frequently if the patient has preserved renal function. Contrast subclavian and auxillary venogram provides a clear anatomical picture and facilitates direct venopuncture . We propose the use of a micropuncture technique to reduce the severity of bleeding in case of inadvertent arterial punctures . A generator pocket formed between the deep fascia and the pectoral muscle probably has less bleeding risk than an intramuscular pocket, however, there are no comparative data to draw clear conclusions. Although the fibrous capsule surrounding the CIED generator often has ample vascular supply and may prone to bleed than new implantation, there is no controlled study available for comparison. In a multicenter prospective study of complications related to CIED generator replacement, Pooles et al. reported the rates of hematoma requiring surgical evacuation were 0.7% in patients had generator change only and significantly higher at 1.5% in those with upgrade and transvenous lead additions . Careful intraoperative hemostasis is crucial, especially if the patient is on the continued warfarin therapy. We usually avoid the practice of temporary placement of gauzes into the pocket during the operation to decrease the risk of delayed bleeding and hematoma formation after pocket closure. Application of sterile pressure dressings on the wound is a common practice although its duration and effectiveness have not been studied. Finally, the practice of sealants injected into the pocket before incision closure remains to be controversial [21,37].