Local stabilization of cardiac wall motion is critically important for achieving accurate anastomoses [1]. The heart can be appropriately positioned by pulling on multiple or single DPS, placed in the posterior pericardium [1, 2]. During DPS stitching, great caution should be taken to avoid serious bleeding. Although this complication seems rare because, to our best knowledge, only four case reports have been published [3,4,5,6], DPS may cause life-threatening bleeding. In one out of the four published cases, the patient died because of aortic injury [3]. In the remaining three cases, all authors suggested the preoperative administration of tissue plasminogen activator, the postoperative administration of low molecular weight heparin, and the postoperative administration of double antiplatelet agents presumably increased the bleeding [4,5,6]. In contrast, in our two cases, no agents relating to coagulation cascade or platelet function, except a low dose of aspirin or preoperative heparin infusion, were administered. When we detected bleeding, activated clotting time, platelet count, and fibrinogen level were 104 s, 8.2 × 104/μL, and 242 mg/dL in case 1, and 110 s, 8.0 × 104/μL, and 359 mg/dL in case 2, respectively. The present cases suggest that DPS can cause serious bleeding complication, even in the absence of aggressive medication for fibrinolysis, anticoagulation, or antiplatelet aggregation.
Zamvar et al. mentioned that sufficient deflation of the lung before DPS created more room for surgeons to avoid the lung injuries [4]. While complete deflation of the lung was performed in these two cases to prevent injury to organs or tissues adjacent to the pericardium, injuries could not be avoided. Based on this, we have to keep in mind that lung deflation is not a fail-safe means of preventing organ or tissue injuries.
TEE was a useful tool for detecting bleeding complications in the thorax, pericardium, and para-aortic space [4,5,6]. Intrathoracic fluid or blood accumulation is often encountered during cardiac surgery and is easily visualized using TEE with the counterclockwise rotation of the probe from the mid-esophageal four-chamber view, considering the left-sided accumulation in a patient in a supine position. Typically, fluid or blood accumulates in the dorsal and caudal portion of the pleural space, i.e., at the bottom of the left thorax beside the descending aorta [7]. In contrast to this, hematomas due to vessel injury by DPS are localized at the bottom of the left-sided thorax as well as, to a certain extent, in the field adjacent to the injury site. Therefore, presence of the latter is typical of this DPS complication. Indeed, we detected numerous hematomas, including a giant one at the bottom of the thorax in both cases. The area surrounding the LLPV immediately behind the pericardium in case 1 and the wide area along with the diaphragm in case 2 are notable examples for the localization of the injury site. The previous reports identified the aorta, pulmonary veins, esophagus, and lung as organs susceptible to injuries by DPS [3,4,5,6]. Our case 2 suggested that the diaphragm also requires attention during DPS stitching.