MYOCARDIAL ABSCESS COMPLICATED BY COMMUNICATION WITH THE RIGHT ATRIUM: A SOURCE OF SEPSIS AND THROMBOTIC EVENTS
INTRODUCTION: Myocardial abscesses are a serious and life-threatening condition that can originate as a complication of infective endocarditis or systemic infection. A variety of organisms are involved, but the most common is Staphylococcus aureus. Patients affected by myocardial abscesses typically have significant comorbidities that place them at risk, including malignancy, alcoholic hepatic disease, chronic renal failure, congestive heart failure, stroke, or various collagen diseases. The diagnosis of myocardial abscess can be aided by imaging, with transesophageal echocardiography (TEE) being highly sensitive and specific. Here we report a case of several complications arising from an aortic root abscess with communication into the right atrium in a patient with preexisting malignancy.
CASE DESCRIPTION: A 55-year-old female presented to the hospital twice within a span of several months for sepsis. She had a complex prior medical history of rheumatic heart disease with mechanical mitral valve replacement in 2013 and aortic insufficiency with mechanical aortic valve replacement in 2013. In addition, she had non-metastatic breast cancer for which she had received three rounds of chemotherapy, chronic obstructive pulmonary disease, coronary artery disease and congestive heart failure. On her first presentation, she had complaints of abdominal pain, respiratory distress and fever. She was admitted to the ICU for neutropenic fever and septic shock secondary to Escherichia coli (E. coli) pneumonia. On admission, she required intubation, vasopressors, and was started on broad spectrum antibiotics. Bronchial cultures grew E. coli and her blood cultures were negative. She later developed Clostridium difficile colitis. She continued to require ventilatory support throughout her stay in the ICU and a tracheostomy was subsequently placed. After this, she was weaned from vasopressors, her respiratory status improved and she was discharged to a nearby long-term acute care hospital (LTACH).
Five weeks later at the LTACH, she developed fever and leukocytosis. Sputum and blood cultures were obtained, including one set from her chemotherapy port placed three and a half months prior, which grew Methicillin Resistant Staphylococcus aureus (MRSA). Tissue samples from the port site also grew MRSA. She was started on broad spectrum antibiotics and Interventional Radiology removed the port. After nearly seven weeks at the LTACH, and two weeks after being diagnosed with MRSA bacteremia, the patient began to complain of left lower leg pain. Her left lower extremity appeared mottled and cool with non-palpable pulses. She was immediately transferred back to the primary hospital where she was admitted for complete occlusion of the distal left common femoral artery and proximal superficial femoral artery. On the second day of her readmission, she became hypotensive requiring vasopressors. She underwent a TEE for concerns of a septic emboli secondary to presumed MRSA prosthetic valve endocarditis. The TEE revealed large vegetations and an aortic root abscess adjacent to the mechanical aortic valve, which had perforated from the aortic root into the right atrium. There were additional smaller vegetations seen on the mechanical mitral valve. Later that night, the patient continued to decompensate and suffered a cerebral vascular accident resulting in right sided deficits, likely secondary to septic emboli. Family was notified and the patient was made comfortable. She passed away a few hours later with her husband at the bedside playing the guitar and singing to her.
CONCLUSION: Myocardial abscess with direct communication into the vascular system is rare and carries high mortality. It can be a continued source of recurrent sepsis or emboli and should be suspected in patients with high risk factors, such as those with a history of mechanical valve replacement.