VINDICTIVE VEGETATION: A RARE CASE OF ISOLATED PULMONIC VALVE ENDOCARDITIS

Abstract

SESSION TITLE: Medical Student/Resident Cardiovascular Disease Posters SESSION TYPE: Med Student/Res Case Rep Postr PRESENTED ON: October 18-21, 2020 INTRODUCTION: Endocarditis can affect native or prosthetic heart valves and lead to significant multi-organ injury and mortality. We present a rare case of recurrent isolated pulmonic valve endocarditis (PVE) precipitating severe valvular regurgitation and septic emboli subsequently necessitating surgical intervention. CASE PRESENTATION: A 28 year-old male with history of HIV (CD4 493), Hepatitis C, and intravenous drug use (IVDU) was brought in by ambulance for altered mental status. He was noted to be afebrile, tachycardic to 141 beats/min, tachypnic to 25 breaths/min, and saturating 93% on room air. Laboratory analysis was significant for leukocytosis to 27.2 K/cumm, D-Dimer elevation to 4,321 ng/mL, and urinary toxicology screen positive for amphetamines. Evaluation with CT Thorax demonstrated acute right heart strain, bilateral pulmonary emboli, and regions of lung infarct. A transthoracic echocardiogram visualized a 1.8 cm x 1.2 cm vegetation on the pulmonic valve complicated by leaflet destruction and severe regurgitation. The patient was found to have Streptococcus Viridans bacteremia and was treated with six weeks of IV Penicillin G. A repeat echocardiogram confirmed a persistent 16mm x 4mm pulmonic vegetation, and he consequently underwent surgical valve replacement. Valvular pathology revealed necrosis, myxoid degeneration, and aggregates suspicious of bacterial colonies. Two months later, the patient returned with dyspnea. A large amount of vegetation obstructing flow through the pulmonic bioprosthetic was discovered, with evidence of severe valvular stenosis and interval development of right ventricular systolic dysfunction. Blood cultures grew E. Faecalis and he was treated with six additional weeks of antibiotics. He was hospitalized multiple times over the following year for heart failure symptoms, however was not a candidate for repeat valve replacement due to continuous IVDU. He succumbed to in-hospital PEA arrest and, despite resuscitation efforts, passed away. DISCUSSION: Right-sided endocarditis is infrequently encountered and is often associated with IVDU, HIV, congenital heart disease, and central venous catheters (1). There is scant data on isolated pulmonic valve involvement, which has an estimated prevalence of 1.5-2% of all endocarditis cases (2). While studies suggest that PVE often follows a benign course with appropriate antibiotic therapy, our case illustrates the severity of potential complications. Current guidelines suggest surgical management in patients with right-sided involvement who have persistent infection, evidence of severe valve dysfunction/heart failure symptoms, vegetation ≥ 2 cm, or for prevention of further septic emboli (3). CONCLUSIONS: Isolated PVE remains a challenging diagnosis as cardiac manifestations may initially be silent, emphasizing the need for heightened clinical suspicion in immunocompromised patients presenting with respiratory symptoms. Reference #1: Cahill TJ & Prendergast BD. Infective Endocarditis. Lancet. 2016; 387(10021):882-93. Reference #2: Chowdhury MA & Moukarbel GV. Isolated Pulmonary Valve Endocarditis. Cardiology. 2016;133(2):79-82. Reference #3: AATS Surgical Treatment of Infective Endocarditis Consensus Guidelines Writing Committee Chairs, Pettersson GB, Coselli JS, et al. 2016 The American Association for Thoracic Surgery (AATS) Consensus Guidelines: Surgical Treatment of Infective Endocarditis: Executive Summary. J Thorac Cardiovasc Surg. 2017;153(6):1241-1258.e29. DISCLOSURES: No relevant relationships by Serena Ghanshani, source=Web Response No relevant relationships by Katherine Loomis, source=Web Response No relevant relationships by Andrea Lu, source=Web Response