Transcatheter aortic valve replacement associated infective endocarditis case series: broadening the criteria for diagnosis is the need of the hour

BACKGROUND: Transcatheter valve replacement (TAVR) is an important therapeutic intervention for patients with aortic valve stenosis. As TAVR has become available to a broader population, there has been an increase in the number of less common, yet potentially catastrophic, complications. TAVR related infective endocarditis (TAVR-IE) is a rare, but potentially fatal, complication. CASE SERIES: We present here two patients that we encountered for TAVR associated infective endocarditis. Our first patient presented 5 weeks after his TAVR. His initial presentation was consistent with signs of sepsis. The patient then developed Mobitz type I block during hospital course. His TEE was negative for features of infective endocarditis. Due to high suspicion, patient was taken for surgical exploration and was found to have multiple foci of vegetation adhered to the stent frame. Our second patient presented with new onset pulmonary edema, worsening heart failure and systemic inflammatory response. A TEE was done for persistent MSSA bacteremia which showed stable prosthetic valve function with no signs of infective endocarditis. Patient was discharged with a prolonged course of intravenous antibiotics. Patient was re-admitted for worsening sepsis and blood cultures were positive for MSSA. Patient was taken for surgical exploration of his prosthetic aortic valve which showed purulent aortic root abscess. CONCLUSION: Through these cases, we aim to raise awareness on TAVR-IE. Due to the atypical clinical presentation, the modified Duke criteria may not be sufficient to diagnose TAVR-IE. Transesophageal echocardiogram in TAVR-IE may be negative or indeterminate. Prosthetic valve shadow may obscure smaller vegetations and/or smaller abscesses. A negative transesophageal echocardiogram should not rule out TAVR-IE and further diagnostic imaging modalities should be considered. PET/CT after administration of 18F-FDG (fluorodeoxyglucose) is a useful diagnostic tool in the diagnosis of infective endocarditis where TEE has been negative or inconclusive. Multi-modal imaging, in addition to the modified Duke criteria, can facilitate early diagnosis and improved mortality outcomes. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12872-021-02364-0.