**14. Miscellaneous gastrointestinal and abdominal complications related to cardiac surgery**

Among less commonly encountered (and reported) complications of cardiac surgery are those associated with trans-esophageal echocardiography (TEE). Likely under-reported, TEE-related complications in cardiac surgical patients occur in as many as 1.2% of patients [70]. In one series, esophageal and gastric tears were seen within 24 hours of the TEE in 2 patients, with additional gastric ulceration and gastric tear seen within 5 days of the proce‐ dure. Moreover, gastric perforations were described presenting between 4-11 days post-TEE. Among the 6 reported cases, 3 required a laparotomy, 2 were treated endoscopically, and 1 patient required transfusion [70].

Epigastric (sub-xiphoid) and chest tube site hernias [71] following cardiac surgery occur in as many as 3-4% of patients following median sternotomy [72]. Another, much less common com‐ plications related to the mediastinal tube thoracostomy is superior epigastric artery pseudoa‐ neurysm [73]. Management of these rare conditions is mostly surgical, although minimally symptomatic high-risk surgical patients may be followed with clinical observation.

Due to the growing volume of mechanical cardiac and pulmonary assistive technologies (i.e., ventricular assist devices, intra-aortic balloon pumps, extra-corporeal membrane oxy‐ genation devices), it is important to mention potential gastrointestinal and abdominal com‐ plications associated with these devices. Not unexpectedly, the use of cardio-respiratory mechanical assistive devices has been found to be associated with clinically significant ab‐ dominal and gastrointestinal complications [32, 74, 75]. For example, extracorporeal mem‐ brane oxygenation has been associated with embolic phenomena of the systemic circulation, end-organ ischemia, gastrointestinal hemorrhage, and abdominal compartment syndrome [74, 76-78]. Patients who undergo ventricular assist device placement are also exposed to a number of potential gastrointestinal and abdominal complications, including abdominal in‐ fection, bowel injury, acalculous cholecystitis, pancreatitis, various hernias (i.e., incisional, inguinal, diaphragmatic), peritoneal fluid leaks, and mesenteric ischemia [75, 79-83]. Of note, gastrointestinal hemorrhage has also been reported in patients with ventricular assist devices [84, 85], with higher bleeding rates seen among recipients of non-pulsatile devices as compared to pulsatile devices [86]. There is a trend toward higher mortality among patients receiving ventricular assist devices who experience abdominal complications [75]. Intraaortic balloon pumps are among known risk factors for gastrointestinal complications fol‐ lowing CTS [8, 32]. Some of the reported GIC associated with intra-aortic balloon pump use include gastrointestinal bleeding, bowel ischemia, and pancreatitis [78, 87, 88].
