# Stuck between a rock and a hard place: heart failure with bilateral atrial appendage thrombi and disseminated intravascular coagulation—a case report

## TL;DR

A rare case of heart failure and blood clotting complications caused by a bacterial infection is reported, highlighting the need for increased awareness of this emerging pathogen.

## Contribution

First reported case of concomitant cardiac thrombosis due to DIC in the context of Morganella morganii infection.

## Key findings

- Simultaneous left and right atrial appendage thrombosis occurred in a patient with heart failure and AF.
- DIC was diagnosed in the context of M. morganii infection, leading to severe coagulopathy and bleeding.
- This case emphasizes the rare but serious complications of M. morganii infection in cardiac patients.

## Abstract

The simultaneous occurrence of left atrial appendage (LAA) and right atrial appendage (RAA) thrombosis is a rare finding in atrial fibrillation (AF). In addition, concomitant conditions, such as heart failure (HF) and disseminated intravascular coagulation (DIC), could be associated with intracardiac thrombosis. Morganella morganii is an emerging pathogen, and the association with DIC and cardiac thrombosis is not yet described.

A 69-year-old Caucasian man was admitted to the hospital for progressive dyspnoea and new-onset diarrhoea. His physical examination revealed signs of HF and new-onset AF; laboratory tests showed marked thrombocytopaenia and coagulopathy. Blood and urine cultures were positive for M. morganii, and the International Society on Thrombosis and Hemostasis criteria were diagnostic for DIC. Transthoracic echocardiogram revealed a large, mobile left atrial mass and severely reduced left ventricular function. Transoesophageal echocardiogram showed two masses: one in the LAA and one in the RAA. Positron emission tomography/computed tomography scan excluded infective endocarditis and malignancies. After the beginning of antibiotic therapy and anticoagulation, the patient developed severe bleeding. Unfortunately, his haemodynamic status was complicated by multi-organ failure, and at the end, he developed irreversible cardiogenic shock. We present this challenging case of HF and AF complicated by DIC in the context of M. morganii infection.

Multiple mechanisms, such as inflammatory storm, activation of coagulation cascade, and amplified immune response, may explain the hyper-coagulable state related to DIC. In our case, HF, AF, and DIC may have facilitated RAA thrombosis, which is a rare finding. To the best of our knowledge, this is the first reported case of concomitant cardiac thrombosis as a complication of DIC in the context of M. morganii infection. This highlights the need among clinicians for an increased awareness about this pathogen and the complications of its infection.