Acute Massive Bilateral Lower Extremity Edema After Flying: Beyond Thromboembolic Disease

Abstract

INTRODUCTION: Acute massive bilateral lower extremity edema after long flights is classically associated with venous thromboembolism (VTE). We present a case where a long flight unmasked occult constrictive pericarditis. CASE PRESENTATION: 75 year old male presented acutely after an international flight with complaints of abdominal fullness, mild dyspnea on exertion, and significant new lower extremity swelling. Review of symptoms revealed no chest pain, orthopnea or paroxysmal nocturnal dyspnea but was positive for a viral respiratory illness 8 months prior. Physical exam was remarkable for 4+ bilateral lower extremity edema up to thighs and decreased air entry at left lung base. No JVD, ascites or organomegaly was present and he had normal oxygen saturation. EKG and cardiac enzymes were unremarkable; BNP was mildly elevated. Renal, thyroid and liver labs were unremarkable. VTE causing vascular obstruction was high on our differential. Lower extremity dopplers were negative, but CT Abdomen showed inferior vena cava (IVC) opacification and prominent IVC and iliac veins. Subsequent MRI, however, was negative for IVC thrombus. Chest XRay revealed left pleural effusion. Initial transthoracic echo (TTE) showed questionable abnormal ventricular septum motion, normal LV and RV size and function, and no valvular abnormalities. After some improvement on diuretics, due to patient preference, he was discharged with plans for outpatient evaluation of any underlying cardiac dysfunction. Stress echo was negative for ischemia, but confirmed diastolic interventricular septal bounce and respirophasic variation across the mitral and tricuspid valves, suggestive of constrictive pericarditis. Cardiac MRI revealed diffuse pericardial thickening (as much as 7mm at inferolateral RV). Catheterization demonstrated equalization of right and left diastolic pressures, consistent with constrictive physiology. Because of his progressive symptoms despite trial of colchicine and diuretics, he underwent pericardiectomy, with pathology showing extensive fibrosis without fibrin exudates or acute inflammatory infiltrates. Patient's symptoms resolved postoperatively. DISCUSSION: Acute massive bilateral lower extremity edema after immobilization is often caused by vascular obstruction secondary to VTE. A rarer cause is occult constrictive pericarditis. In such patients, immobilization causes hemodynamic strain, which can precipitate acute massive edema. Delayed diagnosis can impact timing of total pericardiectomy which affects mortality. CONCLUSIONS: The differential of acute massive bilateral lower extremity edema after immobilization should include occult constrictive pericarditis, after excluding more common etiologies.