Title : A case of sepsis-induced Takotsubo cardiomyopathy precipitating torsades de pointes
Abstract:
Background: Takotsubo cardiomyopathy (TCM) is a state of left ventricular (LV) dysfunction induced by a hypercatecholaminergic milieu, leading classically to apical dyskinesis with a compensatory hyperdynamic base. We present a case of sepsis-induced TCM complicated by torsades de pointes (TdP), a polymorphic ventricular tachycardia (PMVT) associated with a prolonged QT interval.
Case: A 76-year-old female with atrial fibrillation presented with severe abdominal pain. She was found to be in septic shock with C. perfringens bacteremia from a tubo-ovarian abscess and underwent hysterectomy. Postoperatively, she was started on intravenous amiodarone for rapid atrial fibrillation, with conversion to sinus bradycardia with frequent premature ventricular complexes. On day 4, she developed episodes of pulseless PMVT. Telemetry showed a prolonged QT interval with a “short-long-short” cycle-length sequence before the onset of TdP. EKG showed sinus bradycardia, left bundle branch block, and a corrected QT interval of 591 ms. Coronary angiography revealed no obstructive coronary disease. Transthoracic echocardiography (TTE) showed apical-predominant LV dysfunction, consistent with TCM.
Decision-Making: Electrolytes were repleted, and amiodarone discontinued. The patient continued in sinus bradycardia with frequent episodes of R-on-T mediated PMVT. Beta-blockers, a mainstay in the treatment of TCM, could not be initiated due to concerns that worsening bradycardia would precipitate TdP. Rather, isoproterenol was administered for overdrive suppression of PMVT. Pacemaker implantation was considered to facilitate the initiation of beta-blockers for TCM and wean isoproterenol. However, this was relatively contraindicated due to bacteremia. Isoproterenol was eventually weaned, and low-dose carvedilol was started. Repeat TTE showed improved LV function. Repeat EKG showed reduction of the QTc interval from 591 to 455 ms, supporting the diagnosis of acquired long QT syndrome attributed to TCM.
Conclusion: TCM can provide both substrate and triggers for TdP. Recognizing the complex interplay between TCM and TdP is crucial for timely intervention and may improve patient prognosis.
