Patient with Presumed Asthma Develops Flash Pulmonary Edema Secondary to Undiagnosed Cor Triatriatum

ABSTRACT

INTRODUCTION: A patient with presumed status asthmaticus, treated with beta-agonist and fluid resuscitation, developed flash pulmonary edema and respiratory failure in the setting of undiagnosed cor triatriatum. DESCRIPTION A teen male with history of asthma developed dyspnea and chest pain at work. At a local emergency room (ER), he received albuterol, steroid, magnesium sulfate, and 2 liters (L) of fluid. Chest X-ray (CXR) and computed tomography of the chest were normal. He was transferred with a diagnosis of status asthmaticus. On exam in the pediatric ER, he had tachycardia, tachypnea and diffuse wheezing. He received albuterol 20mg/hour and 3L of fluid boluses over several hours. Despite improvement in wheezing, the patient had ongoing tachycardia and chest pain. He was placed on oxygen by high-flow nasal cannula. Repeat CXR exhibited new diffuse airspace opacities, and a focused cardiac ultrasound showed a hyperdynamic left ventricle (LV) with normal function. The patient began to expectorate pink frothy fluid, with hypoxemia, requiring intubation. Covid-19 PCR, Troponin-I and B-Type Natriuretic peptide were negative. An echocardiogram revealed a dilated left atrium (LA) with an echogenic membrane within the LA, separating the pulmonary venous chamber from the LA and restricting blood flow into the LV. The LV was small in size with normal function. The right heart was normal. These findings were consistent with diagnosis of cor triatriatum sinister, whereby the LA is divided into two compartments by a membrane that can variably obstruct flow into the LV. For this patient, treatment with beta-agonist caused tachycardia and decreased LV filling. Fluid resuscitation increased intravascular volume. This combination worsened obstruction of blood flow from the LA to the LV, leading to flash pulmonary edema, respiratory failure, and shock. In the ICU, the patient underwent diuresis, and the cor triatarium membrane was later surgically resected. DISCUSSION: Asthma is encountered commonly in children. Patients not responsive to treatment for respiratory distress should have alternative diagnoses considered. Multiple cognitive biases led to delayed recognition of cardiac etiology as the cause for this patient's respiratory failure, including anchoring bias with premature closure.