Abstract Body (Do not enter title and authors here): Leadless pacemakers (LPMs) represent a significant advancement in cardiac pacing technology, offering several advantages over traditional transvenous systems. However, they are not without complications such as leadless pacemaker-induced cardiomyopathy (LPM-CMP). We present a case of cardiogenic shock from LPM-CMP requiring cardiac resynchronization therapy (CRT) as a rescue strategy.

A 77-year-old female with a history of heart failure with reduced ejection fraction, coronary artery disease status post recent percutaneous coronary intervention to the proximal-to-mid left anterior descending artery, complete heart block status post LPM implantation, and chronic kidney disease stage 3b, presented to the emergency department after a syncopal event. Initial vital signs were blood pressure 96/64 mmHg and heart rate 62 bpm, while LPM interrogation showed 100% right ventricular pacing burden. Physical exam revealed congestion with jugular venous distension and 2+ pitting bilateral lower extremity edema. Initial labs (BNP 4792 pg/mL, hs-troponin 202 ng/L, lactate 5.5 mmol/L, AST/ALT 68/30 U/L, and creatinine 3.3 mg/dL (baseline 1.5 mg/dL)) were consistent with SCAI Stage B cardiogenic shock. She was transferred to the cardiovascular intensive care unit for inotropic and vasopressor support. By hospital day 10, she was on 10 mcg/kg/min of dobutamine, 3 mcg/min of epinephrine, and 14 mcg/min of norepinephrine. Despite this and extensive diuresis, she continued to deteriorate. After ruling out acute coronary syndrome, LPM-CMP was suspected as the etiology, and CRT-D was implanted on day 14. Echocardiography-assessed stroke volume correspondingly improved from 25 mL on pressors to 30 mL after CRT-D and off pressors. She was subsequently optimized on heart failure guideline-directed medical therapy, and discharged home on day 19.

LPM-CMP is a rare but potentially serious complication of LPM implantation. Early recognition and appropriate management are essential for optimizing patient outcomes. In this case, CRT-D implantation proved to be a successful intervention, resulting in significant clinical improvement and symptom resolution. This underscores the importance of individualized patient management and the role of advanced device therapies in the treatment of LPM-induced complications. Further research is needed to better understand the risk factors, pathophysiology, and optimal management strategies for LPM-CMP, especially as a rescue strategy in cardiogenic shock.