THE PATH OF LEAST RESISTANCE: CHRONIC INDWELLING CATHETER COMPLICATIONS OF FIBRIN SHEATH FORMATION IN A PATIENT WITH PERICARDIAL COLLATERALIZATION

Abstract

SESSION TITLE: Medical Student/Resident Pulmonary Manifestations of Systemic Disease Posters SESSION TYPE: Med Student/Res Case Rep Postr PRESENTED ON: October 18-21, 2020 INTRODUCTION: Pericardial collateralization and extrapulmonary shunting due to coexistent superior vena cava (SVC) and inferior vena cava (IVC) fibrin sheaths is rare but should be considered in patients with hypotension and hypoxemia with history of vascular catheterization. CASE PRESENTATION: A 33 year old male with end stage renal disease due to congenital kidney disease and chronic hypotension was admitted with recurrent falls. Vital signs showed marked hypotension and hypoxemia requiring vasopressor support and high flow oxygen. No facial plethora or extremity edema was seen on exam. Laboratory testing did not reveal leukocytosis or metabolic abnormalities. Non-invasive hemodynamic monitoring was indicative of distributive and mild cardiogenic shock. CT thorax showed a right lobar consolidate and an occluded proximal SVC with prominent pericardial collateral vessels. CT abdomen and pelvis demonstrated a long tubular intravascular opacity, which was possibly a fibrin sheath from the IVC into the right common femoral vein. Echocardiogram bubble study revealed left sided bubbles that appeared first before right sided bubbles reflective of intracardiac versus intrapulmonary shunt. The patient was treated for pneumonia and weaned off vasopressors in anticipation of possible cardiothoracic surgery. DISCUSSION: Venous stenoses are sequela of central venous hemodialysis catheter access in 41% of dialysis patients (2). We postulate that prior indwelling dialysis catheter placement in this patient contributed to fibrin sheath formation. As a result, a right to left shunt may have arisen with associated pericardial collateral circulation, contributing to hypoxemia through shunt physiology. This may have chronically impeded preload to the right heart, thus lowering stroke volume and cardiac output. The extent of collateralization was not fully seen on imaging, but it is possible some portion of venous return is bypassing the heart entirely and contributing to hypotension. Among the reported cases of patients with systemic-to-pulmonary collateral vessel circulation and shunt, the involvement of both the SVC and IVC has not been characterized (1). Furthermore, reports of patients with collateral pathways from prior catheters and shunts show good hemodynamics in stark contrast to our case (3). CONCLUSIONS: Chronic indwelling dialysis catheter use can result in fibrin sheath formation in the vessel, leading to stenoses of the SVC and IVC. In turn, pericardial circulation can develop which then functions as a right to left shunt. This is potentially the etiology of hypoxia or hypotension in our patient. This should be recognized as one of the complications of long-term indwelling catheters in the SVC or IVC. Reference #1: Kapur, S. et.al. “Where There is Blood, There is a Way: Unusual Collateral Vessels in Superior and Inferior Vena Obstruction” RadioGraphics 2010; 30:67-78 Reference #2: MacRae JM, Ahmed A, Johnson N, et al. “Central vein stenosis: a common problem in patients on hemodialysis”. ASAIO J. 2005;51:77–81. doi: 10.1097/01.MAT.0000151921.95165.1E Reference #3: Gamet A, et.al. “Acquired Systemic-to-pulmonary Venous Shunt or Persistent Left Superior Vena Cava? A Rare Right-to-left Shunt Case-based Discussion.” J Cardiovascular Echogr. 2017 Jul-Sep;27(3)104-106 doi: 10.4103/jcecho.jcecho_42_16 DISCLOSURES: No relevant relationships by Jaskiran Khosa, source=Web Response no disclosure on file for Steve Lee