Intraoperative management of accelerated idioventricular rhythm triggered by tourniquet deflation: a case report and mechanistic insights

BACKGROUND: Accelerated idioventricular rhythm (AIVR) is a common reperfusion arrhythmia, but reports of AIVR triggered by tourniquet deflation in orthopedic trauma surgery are rare. CASE PRESENTATION: A 59-year-old male with left tibiofibular open fracture underwent emergency open reduction and internal fixation. Recurrent AIVR and severe hemodynamic instability occurred twice immediately after tourniquet deflation, with wide QRS complexes, atrioventricular dissociation, and transient ST-segment depression, which was initially misdiagnosed as acute myocardial ischemia. The arrhythmia resolved rapidly after hemodynamic support and rewarming without antiarrhythmic drugs, and the patient recovered uneventfully. CONCLUSION: Tourniquet-induced AIVR is a multifactorial reperfusion-related arrhythmia that can easily be misdiagnosed as myocardial ischemia. It is usually self-limited and responds well to hemodynamic optimization. Strict tourniquet management and prompt differential diagnosis can improve perioperative safety in orthopedic surgery.