What is the recommended approach to diagnosing and managing peri‑operative arrhythmias in an adult surgical patient, including treatment of sinus tachycardia, atrial fibrillation/flutter, ventricular tachycardia, and symptomatic bradyarrhythmias?

Management of Perioperative Arrhythmias

For perioperative arrhythmias, immediately correct reversible causes (hypoxia, electrolyte abnormalities, hypovolemia) while using beta-blockers as first-line pharmacologic therapy for rate control in hemodynamically stable patients, reserving cardioversion for those with hemodynamic compromise. 1

Initial Assessment and Correction of Reversible Causes

Before reaching for antiarrhythmic medications, systematically evaluate and correct the underlying triggers:

• Check and correct electrolyte abnormalities immediately, particularly potassium (maintain ≥4.0 mEq/L) and magnesium, as these are frequent precipitants of perioperative arrhythmias 1, 2
• Assess for hypoxemia and provide supplemental oxygen if oxygen saturation is low 1, 3
• Evaluate for hypovolemia from blood loss or inadequate fluid resuscitation, which causes compensatory tachycardia 1, 2
• Optimize pain control, as inadequate analgesia perpetuates tachycardia through heightened sympathetic tone 2, 3, 4
• Rule out myocardial ischemia, especially if the patient has known or suspected coronary artery disease 1
• Obtain a 12-lead ECG to characterize the rhythm and identify the specific arrhythmia type 1, 2, 3

Management of Supraventricular Arrhythmias and Atrial Fibrillation

Atrial Fibrillation/Flutter (Most Common Perioperative Arrhythmia)

Beta-blockers are the most effective first-line treatment for ventricular rate control in perioperative atrial fibrillation, superior to both digoxin and calcium channel blockers 1. Beta-blockers not only control rate but also accelerate conversion to sinus rhythm compared to diltiazem 1.

• For rate control in stable patients: Use intravenous beta-blockers (esmolol, metoprolol) or nondihydropyridine calcium channel blockers (diltiazem, verapamil) 1
• For patients with heart failure or reduced ejection fraction: Use amiodarone as first-line therapy, as digoxin is frequently ineffective in high adrenergic states like surgery 1
• Avoid digoxin in the acute perioperative setting due to heightened sympathetic tone making it less effective 1, 4
• Do not cardiovert minimally symptomatic atrial fibrillation until underlying problems are corrected, as spontaneous conversion is common and cardioversion is unlikely to maintain sinus rhythm if the precipitating cause persists 1
• Reserve electrical cardioversion for hemodynamically unstable patients with sustained arrhythmias causing compromise 1
• Balance anticoagulation benefits against postoperative bleeding risk based on individual clinical situation 1, 3

Supraventricular Tachycardia (SVT)

For sustained, regular, narrow-complex tachycardia, attempt vagal maneuvers first (Valsalva, carotid massage), followed by intravenous adenosine if unsuccessful. 1

• Prevent recurrences with beta-blockers, calcium channel blockers, or class IC antiarrhythmic agents in the postoperative setting 1
• Avoid digoxin and calcium channel blockers in patients with pre-excited atrial fibrillation (Wolff-Parkinson-White syndrome) 1

Management of Ventricular Arrhythmias

Ventricular Tachycardia

Presume wide-QRS tachycardia to be ventricular tachycardia until proven otherwise, and never use calcium channel blockers (verapamil, diltiazem) to terminate wide-QRS-complex tachycardia of unknown origin. 1

• For hemodynamically stable VT: Treat with intravenous beta-blockers, lidocaine, procainamide, or amiodarone 1
• For hemodynamically unstable VT: Perform immediate electrical cardioversion 1
• Evaluate for myocardial ischemia as the underlying cause, especially if ischemia is suspected or cannot be excluded 1
• For recurrent sustained polymorphic VT: Amiodarone is reasonable in the absence of long QT syndrome 1

Torsades de Pointes

• Withdraw offending drugs and correct electrolyte abnormalities immediately 1
• Administer magnesium sulfate for patients with torsades de pointes and long QT syndrome 1
• For torsades with sinus bradycardia: Use beta-blockade combined with temporary pacing 1
• For recurrent, pause-dependent torsades without congenital long QT: Use isoproterenol 1

Premature Ventricular Contractions

Do not treat unifocal or multifocal premature ventricular contractions with antiarrhythmic therapy unless they are symptomatic or cause hemodynamic compromise. 1, 3

• Asymptomatic ventricular arrhythmias, including couplets and nonsustained VT, are not associated with increased cardiac complications after noncardiac surgery 1
• For patients with ejection fraction <35%, heart failure, and nonsustained VT: Consider referral to electrophysiology for ICD evaluation for primary prevention 1

Management of Bradyarrhythmias

Perioperative bradyarrhythmias usually respond well to short-term pharmacological therapy; temporary cardiac pacing is rarely required. 1

• Acute pharmacologic management: Use intravenous atropine as first-line; aminophylline may also be effective 1
• Identify and correct underlying causes: Medications, electrolyte disturbances, hypoxemia, or ischemia 1
• Indications for temporary or permanent pacing: Complete heart block or symptomatic asystolic episodes 1
• Asymptomatic bifascicular block (with or without first-degree AV block) is NOT an indication for temporary pacing, but have an external pacemaker available for transcutaneous pacing 1
• For sinus node dysfunction or complete heart block: Temporary or permanent transvenous pacing using the same indications as for elective permanent pacemaker implantation 1

Critical Pitfalls to Avoid

• Never use class IC antiarrhythmic drugs in patients with a history of myocardial infarction 3
• Never use calcium channel blockers to terminate wide-QRS tachycardia of unknown origin, especially with myocardial dysfunction 1
• Do not suppress supraventricular premature beats with medication 1
• Do not treat asymptomatic premature ventricular contractions with antiarrhythmic drugs 1, 3
• Avoid acute preoperative potassium repletion in asymptomatic individuals, as this may carry greater risk than benefit 1
• Do not use digoxin as first-line for rate control in the acute perioperative setting due to high adrenergic tone 1, 4

Special Considerations for Patients with Pacemakers/ICDs

• Use bipolar electrocautery instead of unipolar to minimize interference with pacemakers 1
• Position the ground plate correctly and keep electrocautery away from the pacemaker device 1
• Set pacemaker-dependent patients to asynchronous or non-sensing mode during surgery (place magnet over device) 1
• Perform pacemaker interrogation after surgery to ensure appropriate programming 1