2024 FSA Podium and Poster Abstracts

S009: INTRACARDIAC THROMBOSIS DURING LIVER TRANSPLANTATION: A 22-YEAR SINGLE-INSTITUTION COHORT STUDY
Jennifer Lee, DO; Shennen A Mao, MD; Ryan M Chadha, MD; Stephen Aniskevich III, MD; Dana K Perry, MD; Taimur Sher, MBBS; Sher-Lu Pai, MD; Mayo Clinic

Intracardiac thrombosis (ICT) during orthotopic liver transplantation (OLT) is associated with a high mortality rate. This diagnosis requires an intraoperative transesophageal echocardiogram (TEE), but esophageal varices and coagulopathy found in end-stage liver disease (ESLD) patients may deter its usage. Risk factors of ICT may assist clinical judgment on the intraoperative usage of TEE. Existing literature shows that heparin and tissue plasminogen activator (tPA) have been utilized as the treatment of ICT during OLT. This study aims to identify risk factors for ICT during OLT with the secondary aim of examining the incidence, presentation, treatment, survival rate, and postoperative complications in this patient population.

A retrospective chart review was conducted on patients who underwent OLT from January 1, 1998 to December 31, 2019 at our institution. ICT diagnosis was confirmed with visualization by TEE. Each patient’s medical record was abstracted for demographic data, comorbidities, location of ICT, intraoperative management, and outcomes. Coagulation abnormalities were evaluated via prothrombin time (PT), international normalized ratio (INR), and thromboelastogram (TEG) before and after ICT. ICT patients were compared to a non-ICT cohort, matched in age, sex, and Model for End-Stage Liver Disease (MELD) score, in a 1:3 ratio.

Of 3,067 OLTs performed within the study period, 31 (1.0%) patients had TEE visualization of ICT. 93 patients without ICT were in the matching cohort. The primary diagnosis for liver failure complicated by ICT was variable. Preoperative risk factors associated with ICT include a history of chronic kidney disease (CKD) (p= 0.004), gastropathy (p=0.018), and obesity (p=0.045). In the ICT group, the TEG showed no clot intraoperatively in 29 (93.5%) patients compared to 12 (12.9%)  in the non-ICT group (p<0.001).  All 11 patients with left-sided ICT arrested and died intraoperatively. 6 patients with right-sided ICT received heparin and tPA. 5 of the 6 survived but developed strokes. 14 patients with right-sided ICT received heparin only, and 13 patients survived without significant complications. 3 patients with right-sided ICT received heparin and tPA with failure of thrombus dissolution and death. If they survived the intraoperative course, patients with ICT had a statistically significant increase in postoperative adverse outcomes, such as strokes, cardiac complications, increased ICU length of stay, and increased graft failure (Table 1).

Diagnoses of CKD, gastropathy, and obesity showed statistically significant association with ICT development during OLT. Patients with CKD experience delayed clot formation with increased final clot strength and decreased fibrinolysis. Portal hypertensive gastropathy is a known cause of gastrointestinal bleeding and varices and may reflect the severity of liver impairment. It is difficult to speculate the correlation between coagulation cascade and obesity in these patients. However, patients with these risk factors may benefit from routine placement of TEE. Intraoperative flat-line TEG may be a laboratory manifestation of consumptive coagulopathy, such as disseminated intravascular coagulation (DIC), correlating to a high risk of ICT necessitating TEE monitoring. Patients with left-sided ICT had 100% mortality. Patients with right-sided ICT, who received heparin and tPA, developed strokes so we urge postoperative brain imaging to expedite diagnosis.