Refractory Intraprocedural Ventricular Fibrillation From Left Circumflex Culprit Occlusion Managed With Culprit PCI...

Ventricular fibrillation (VF) is a life-threatening complication of acute coronary syndrome (ACS) and requires rapid identification and correction of reversible ischemic triggers. ST-segment elevation in aVR with diffuse ST depression reflects global subendocardial ischemia but is not specific for left main or proximal left anterior descending disease.

A 62-year-old male with prior coronary stent placement presented with acute chest pain, diaphoresis, nausea, and vomiting. An electrocardiogram demonstrated ST-segment elevation in aVR with ST depressions in V3-V6. Laboratory testing demonstrated severe metabolic acidosis (pH 7.07; bicarbonate 10.3 mEq/L), lactate 3.7 mmol/L, and high-sensitivity troponin rising from 427 to 4991 ng/L within 2 h. During emergent angiography, VF developed after left ventricular catheter manipulation and recurred repeatedly while attempting to cross a heavily calcified 99% proximal left circumflex (LCx) lesion. Over 20-30 min, 11 VF episodes required immediate defibrillation, manual chest compressions, and intravenous amiodarone. VF ceased only after LCx stenting restored TIMI Grade 3 flow. The patient's maximum intraprocedural shock severity met SCAI Stage E criteria because of recurrent cardiac arrest, multiple defibrillations, and severe acidosis. An Impella microaxial flow pump was placed for temporary postresuscitation circulatory support and maintained at P4. A postreperfusion echocardiogram obtained during ongoing support showed an LVEF of approximately 60%. The device was removed within 48 h after hemodynamic recovery. Staged intravascular lithotripsy-assisted PCI of the calcified mid-LAD lesion was performed on Day 4.

This case demonstrates that refractory ischemia-mediated VF may terminate only after culprit-vessel reperfusion. A preserved LVEF measured after reperfusion during mechanical support does not exclude earlier SCAI Stage E shock. Short-duration Impella support may serve as an individualized bridge during recovery from recurrent arrest and transient circulatory collapse.