Anticoagulation-free Prolonged Extracorporeal Membrane Oxygenation Use for Massive Pulmonary Hemorrhage in a Child with Heart Transplant and Mechanical Mitral Valve

A 15-year-old boy presented with shortness of breath and generalized malaise for over 3-4 days.

The child had a history of Noonan syndrome.  His medical history included an orthotopic heart transplant at 5 months (due to Noonan syndrome-related heart defects) and a mechanical mitral valve replacement six months prior. He was on warfarin for the mechanical valve with normal INR levels.

On examination, the boy did not have a cough, fever, or other symptoms. He had Noonan facies, tachycardia (158/min), a respiratory rate of 60/min, and an initial SpO2 of 72%, which improved to 86% with oxygen therapy. Clinical examination revealed chest retractions, bilateral lung crepitations, a prominent mechanical S3 heart sound, and other heart murmurs. His abdomen was soft with an enlarged liver, but the neurological examination was normal.

Differential diagnoses included – respiratory infection, pulmonary embolism, acute heart failure, or pulmonary edema from a frozen mechanical mitral valve. 

He was admitted to the ICU, where chest X-ray and echocardiogram revealed a retrocardiac consolidation and worsening mitral valve gradient indicative of thrombosis. 

Enoxaparin was administered, and fluoroscopy showed normal valve function. The patient was intubated due to hypoxic respiratory failure, with frank blood from the endotracheal tube. The CXR showed left lung opacification from severe pulmonary hemorrhage. His hemoglobin dropped to 5.3 g/dL, and INR increased to 4.3.

Treatment included transfusions, nebulized tranexamic acid, recombinant factor VIIa, and bronchoscopy, which revealed fresh blood and clots. Veno-venous ECMO was initiated, and anticoagulation was minimized due to ongoing hemorrhage. Despite severe bleeding complications, including gastrointestinal hemorrhages that required embolization, the patient gradually improved with treatment involving selumetinib and dipyridamole. 

He was discharged after five months with good cardiac function and no further hemorrhage.

This case highlights the effectiveness of veno-venous ECMO in severe pulmonary hemorrhage, even in patients with complex underlying conditions like Noonan syndrome, and the potential to manage mechanical valve therapy without anticoagulation for extended periods.

Source: Anton-Martin P, Sandhu H, Kramer J, et al. Indian Pediatrics Case Reports. 2024 Apr 1;4(2):70-4.