Acute Unilateral Lung Edema Following Reperfusion in a Lung Transplant Recipient: A Case Report Discussing the Role of Double Chambered Right Ventricle

Abstract

<h3>Introduction</h3> Acute unilateral lung edema immediately following reperfusion of newly transplanted lung is rare. We present a case of a hemodynamic collapse with acute lung edema during a sequential single lung transplantation (LTx) for emphysema in a patient with post-operatively diagnosed double-chambered right ventricle (DCRV). <h3>Case Report</h3> A 61-year old woman underwent LTx. Pre-operative trans-thoracic echocardiography (ECHO) showed only mild signs of pulmonary hypertension with a septal bounce sign. Invasively measured pulmonary pressures were normal at induction. One hour following reperfusion of the first transplanted right lung (RL) the graft developed severe edema and the patient developed severe systemic hypotension. Therefore, urgent VA-ECMO was installed. Trans-esophageal ECHO excluded pulmonary vein stenosis (PVS) of the congested lung (<i>Fig 1, A</i>). A biopsy excluded hyperacute rejection (HAR). After 30 minutes of ECMO support recovery of the graft occured (<i>Fig 1, B</i>). ECMO was continued until post-operative day (POD) 2. Computed tomography (CT) on POD 32 revealed RV hypertrophy, RV outflow tract stenosis causing DCRV (<i>Fig 1, D&E</i>) and reduced sternum-spine diameter. (<i>Fig 1, G</i>). Heart catheterization on POD 87 showed a RVOT gradient of 26 mmHg and severe left ventricular (LV) diastolic dysfunction (DD) (end diastolic pressure 33mmHg). <h3>Summary</h3> The differential diagnosis of intra-operative acute unilateral edema after LTx includes primary graft dysfunction (PGD), PVS, HAR or cardiogenic edema. PGD was unlikely due to the nature and evolution of the edema. Cardiogenic origin is possible based on LV DD. This can be due to underlying cardiac disease, acute ischemia or the effect of DCRV (reverse Bernheim effect: <i>Fig 1, F</i>). It is not clear if the DCRV was present before LTx. Our case demonstrates the essential role of proper assessment of both LV and RV morphology and function before LTx.