54: ECpella Support in Refractory Cardiogenic Shock Following Hydrogen Sulphide Poisoning: A Case Report

Introduction: Mechanical circulatory support (MCS) systems such as Veno-Arterial Extracorporeal Membrane Oxygenation (VA-ECMO) have become crucial in managing severe circulatory failure. In recent years, the addition of micro-axial pumps (Impella) has gained prominence for providing active left ventricular (LV) unloading. Their combined use, termed ECPELLA, offers potential for myocardial recovery in profound cardiogenic shock. However, the physiological impact and outcomes of such combined support in toxicological cardiac injury remain poorly understood. Case presentation: A 24-year-old male industrial worker sustained accidental exposure to hydrogen sulphide (H2S) gas for approximately ten minutes. The patient collapsed with sudden loss of consciousness followed by a generalized tonic clonic seizure (GTCS). After brief resuscitation by the emergency rescue team, he was transported to a nearby hospital, where recurrent seizures were controlled with intravenous lorazepam and the patient was intubated for airway protection. He received sodium nitrite 300 mg, hydroxocobalamin 5 mg, and methylene blue 100 mg intravenously. Initial investigations revealed severe metabolic acidosis (lactate 15.2 mmol/L), marked myocardial depression (LVEF 25%) despite normal coronary arteries. Progressive hemodynamic deterioration, worsening hepatic and renal dysfunction prompted initiation of VA-ECMO and transfer to tertiary ECMO centre.On Day 1, intra-aortic balloon pump was inserted for LV unloading. Due to impaired aortic valve opening (LVEF 5–10%), Impella support was added on Day 3 to establish ECpella configuration. Despite maximal circulatory assistance, patient developed a left ventricular thrombus. Surgical thrombectomy planned, but family declined. Patient succumbed to refractory multiorgan failure. Conclusion: We believe that this is the first reported case of ECpella use in hydrogen sulphide–induced cardiogenic shock. Although the outcome was fatal, the case highlights the potential role of early ECpella initiation in managing severe toxic cardiomyopathy secondary to chemical poisoning. Further research is needed to define the optimal timing and prognostic impact of ECpella in toxicologic cardiac injury.