A Rare Occurrence of Cardiogenic Shock after Cardioversion: A Case Report

Background: Atrial fibrillation (AF) is a common cardiac arrhythmia that affects the health and lifespan of people and has been growing in prevalence with the aging population. AF leads to atrial remodeling, which increases the likelihood of developing treatment resistant AF. Risk factors for AF include obstructive sleep apnea, alcohol use, obesity, hypertension, and diabetes. Treatment consists of rhythm control, rate control, and thromboembolism prevention. If a patient fails to convert to sinus rhythm or remains symptomatic despite pharmacological treatment, the next step in management may include Direct Current Cardioversion (DCCV) or catheter ablation. DCCV restores sinus rhythm (SR) by using controlled shocks to the heart and is considered a safe and effective procedure for treating AF. Complications include arrhythmias, skin burns, and cardiac tissue damage. Following the restoration of SR, cardiac output (CO) generally improves. Cardiogenic shock is a rare occurrence after DCCV. This case report details one of these rare occurrences, where a patient with multiple comorbidities developed cardiogenic shock after DCCV for AF. Case Information: A 65-year-old male with a history of heart failure with reduced ejection fraction, AF with prior ablation, atrial flutter, dilated cardiomyopathy, obstructive sleep apnea, chronic kidney disease, and implantable cardioverter defibrillator (ICD), presented to the emergency department (ED) with symptoms of dyspnea and shortness of breath. ECG showed atrial flutter with rapid ventricular response (RVR). Urgent DCCV was performed, restoring SR but precipitating cardiogenic shock, which required intubation and vasopressors. Since stroke volume remains constant in patients with dilated cardiomyopathy, the ICD was reprogrammed to raise the HR. Thereby improving the CO and resolving the cardiogenic shock. The patient remained stable for one month but had recurrent decompensated heart failure. ECG showed AF with RVR with a HR greater than 130 bpm. The patient was cardioverted again to sinus rhythm. However, the patient's condition soon deteriorated, wherein he developed shortness of breath, orthopnea, diaphoresis, and cold extremities. He was intubated due to his respiratory distress and started on milrinone, norepinephrine, furosemide, and an amiodarone drip. He nonetheless converted to AF with RVR, compromising his CO. This was evident clinically by his decrease in urine output, despite furosemide treatment. Urgent AV node ablation with a biventricular ICD upgrade was thus recommended. Postoperatively, as his condition improved, the patient was extubated and switched to oral diuretics. Amiodarone was discontinued, and his heart failure medications were slowly reinstated. Upon discharge, the patient was referred to another facility that specializes in heart failure and transplants. Conclusion: Although DCCV is generally considered a safe and effective procedure, there are still risks associated with it. This case highlights the importance of considering underlying cardiac dysfunction in patients undergoing cardioversion for AF and the need for close monitoring and follow-up in these patients. Since not many cases showcasing these potential complications have been documented, this warrants further research to identify risk factors, complications, and ways to prevent harm to patients who may undergo DCCV.