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Bleeding Complications in Percutaneous Coronary Interventions

and there was a significantly longer delay in patients in whom vascular closure devices (VCDs) were used (median 12 h) compared to those with manual compression (5 h). If true, this effect completely defeats the purpose of these rather costly devices, which are frequently used to facilitate early mobilization and discharge. It is a highly important safety concern with the current trend to discharge patients very early after PCI [4, 5] . Is the conclusion that we should observe patients for a longer period in case of VCD use? Such a conclusion would be premature, for several reasons. This was a retrospective study, and retroperitoneal bleeding was not a prospectively defined endpoint. The study included different VCD types, namely Angioseal (St. Jude Medical), Perclose (Abbott Vascular) and Exoseal (Cordis), and there are potentially relevant differences among these devices [6, 7] . The delayed manifestation of the retroperitoneal bleed in patients after VCD may be explained by the different mechanisms of retroperitoneal hemorrhages ( fig. 1 ): (1) Traumatic: in many cases, the bleeding is related to artery puncture that is above the inguinal ligament. Especially problematic are back wall punctures since they may not be sealed by manual compression or closure devices. Lacerations of the vessel wall or a side branch during advancement of the guidewire or sheath can cause retroperitoneal bleeding. Vascular complications, including retroperitoneal hematomas, account for the majority of complications related to percutaneous coronary interventions (PCIs) and are associated with increased mortality [1] . Retroperitoneal bleeding is particularly dangerous, can develop with nonspecific symptoms and can be difficult to recognize; it is among the causes of unexpected mortality after PCI ( fig. 1 ). In this issue of Cardiology, Eisen et al. [2] study the problem of retroperitoneal bleeding in a cohort of patients undergoing diagnostic or therapeutic angiography in a single center between 2005 and 2011 (n = 26,487 patients). The risk of retroperitoneal bleeding was small (0.18%) but associated with significant mortality. This low incidence of retroperitoneal bleeding is consistent with other reports. Still, it is surprisingly low considering that as many as 21% of the patient cohort received a glycoprotein IIb/IIIa inhibitor and considering the exclusive femoral approach. A possible explanation is that the true incidence of retroperitoneal bleeding was underreported, which is often the case in such retrospectively analyzed studies. Even in prospective trials, the true incidence of retroperitoneal hemorrhage is probably underdetected; only systematic postprocedural imaging and independent event adjudication could reveal the true incidence [3] . An interesting observation was the time to diagnosis of the bleeding. The median interval was 9 h in this study, Received: April 16, 2013 Accepted: April 17, 2013 Published online: June 20, 2013