Heart Rhythm Changes in Patients With Atrial Fibrillation After Cardiopulmonary Bypass: a Retrospective Analysis

The goal of this observational study is to learn about the lthe effect of the tetralogy of medication regimen on intraoperative cardioversion in patients with persistent AF. The main question it aims to answer is:

Does the regimen improve the success rate of cardioversion in patients with persistent AF during cardiac surgery? The treatment protocol commences with the administration of amiodarone, followed by the administration of either all or a portion of the subsequent medications: aminophylline, ephedrine, and isoproterenol.

This observational cohort study was conducted at the Chinese Academy of Medical Sciences Fuwai Shenzhen Hospital using the electronic medical record database, from March 7, 2023, to January 1, 2025. Patients diagnosed with atrial fibrillation who underwent cardiac surgery between June 1, 2000, and January 31, 2023, were included in the study.

Background: Most patients with atrial fibrillation (AF) continue to experience AF following cardiac surgery, which is not conducive to postoperative circulatory stability. Intraoperative active cardioversion has rarely studied due to uncertainty regarding the efficacy of pharmacological cardioversion and the recurrence rate of AF in patients with persistent AF.

Objective: To assess the effect of the tetralogy of medication regimen on intraoperative cardioversion in patients with persistent AF.

Methods: This observational cohort study was conducted at the Chinese Academy of Medical Sciences Fuwai Shenzhen Hospital using the electronic medical record database, from March 7, 2023, to January 1, 2025. Patients diagnosed with AF who underwent cardiac surgery between June 1, 2000, and January 31, 2023, were included in the study. These patients undergoing pharmacological cardioversion during surgery were matched with untreated patients in a 1:1 ratio based on age, sex, weight, diagnosis, beta blocker and digoxin usage, indicators from cardiac ultrasound and blood gas analysis. The treatment protocol commences with the administration of amiodarone, followed by the administration of either all or a portion of the subsequent medications: aminophylline, ephedrine, and isoproterenol. The choice between these drugs depends on the patient's blood pressure and heart rate. The incidence of cardioversion in patients who underwent the tetralogy of medication regimen approach was compared with that of untreated patients. Data analyses took place from March 1, 2024.

Eligibility Criteria:
Inclusion Criteria:

* ASA Ⅱ-Ⅲ,
* Aged 18-70 years,
* Who were scheduled for elective cardiac surgery under general anesthesia,
* Who were diagnosed with atrial fibrillation by preoperative 12-lead electrocardiogram or 24-hour holter electrocardiogram.

Exclusion Criteria:

* Allergic to iodine, amiodarone or its excipients
* Pulmonary fibrosis
* Keratopathy or severe loss of vision or blindness
* Patients with sick sinus syndrome, severe bradycardia (heart rate \&lt;50bpm), second- or higher-degree atrioventricular block
* Preoperative intravenous infusion of amiodarone
* Intraoperative radiofrequency ablation of atrial fibrillation
* The patient is participating in another interventional clinical study.