Intracardiac Abscess and Pacemaker Lead Infection Secondary to Hematogenous Dissemination of Methicillin-Sensitive Staphylococcus Aureus from a Prior Diabetic Foot Ulcer and Osteomyelitis

Abstract

BACKGROUND Intracardiac abscesses are an unusual occurrence in developed countries. With the increase in use of implantable cardiac devices, the increase use of and advancements in antibiotics, and the longevity of patients with cardiac devices, one may expect an increase in such infections; however, case reports are rare. We are presenting a case in which hematogenous dissemination of methicillin-sensitive Staphylococcus aureus (MSSA) infection from a lower extremity diabetic ulcer propagated into an infected pacemaker lead and ultimately an intracardiac abscess of the right atrium. CASE REPORT A 77-year-old male with a history of MSSA diabetic foot infection complicated by osteomyelitis presented with fever, syncope, and wide complex tachycardia, and he was found to have an intracardiac abscess and fibrinous lead vegetations. The patient was deemed too ill for invasive surgical intervention given his comorbidities, pacemaker generator replacement requirement, and intermittent ventricular tachycardia. The patient was subsequently sent home with oral antibiotics and home hospice per patient and family wishes. CONCLUSIONS This case demonstrated how hematogenous dissemination of MSSA infections from a diabetic foot ulcer and osteomyelitis can seed pacemaker hardware resulting in an intracardiac abscess. Unfortunately, our patient was too ill to undergo all procedures required to eradicate the abscess and infected pacemaker hardware. The standard of care would be complete hardware removal. Conservative management would include indefinite or prolonged antibiotic therapy, with the notion that intracardiac abscesses cannot be cured with antibiotics alone. This conservative management approach would be deemed necessary in a select population that cannot undergo surgical intervention.

Figure 1.

TEE (transesophageal echocardiogram) image of 4.07×3.93 cm intramuscular ovoid mass with lucent core with a circumferential hyperechoic ring in the wall of the right atrium encasing the atrial lead indicative of intra-atrial abscess.

Figure 2.

TEE (transesophageal echocardiogram) image utilizing color flow doppler function of the 4.07×3.93 cm intramuscular ovoid mass with lucent core demonstrating that the abscess is not contiguous with the intracardiac blood flow within the right atrial chamber and is confined within the right atrial myocardium.