Arrhythmias and conduction system disorders are common perioperatively with a reported incidence of 4–20% after noncardiac surgery and 15–60% after cardiac surgery.1 Prior to noncardiac surgery, a resting 12-lead electrocardiogram (ECG) is recommended for patients with known coronary artery disease, significant structural heart disease, significant arrhythmia, cerebrovascular disease, or peripheral arterial disease, except for patients undergoing low-risk surgery.2 Comparison with prior ECGs is helpful and detailed cardiac history should be obtained preoperatively from the patient's cardiologist or primary care physician.
There is a paucity of studies addressing the perioperative risk conferred by arrhythmias. Most of the perioperative cardiac risk calculators (e.g., Revised Cardiac Risk Index (RCRI), American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) surgical risk calculator) do not include arrhythmias or conduction system disorders as a predictor of perioperative cardiac complications.
Arrhythmias can be broadly classified as: (a) Tachyarrhythmias – The underlying mechanism is enhanced automaticity, triggered arrhythmias, or reentry, and (b) Bradyarrhythmias – The underlying mechanism is disturbance in impulse formation or disturbance in conduction.
Supraventricular tachyarrhythmias include a variety of rhythms (Figure 13-1) and are more common than ventricular arrhythmias.3,4
Management of Supraventricular Tachyarrhythmias
Approach to Patients Presenting with Supraventricular Tachyarrhythmias
Clinical presentation may include chest pain, dyspnea on exertion, fatigue, palpitations, presyncope, syncope, or rarely cardiac arrest (in case of Wolff-Parkinson White syndrome or severe cardiomyopathy). Electrocardiography (ECG) is the most important test, especially if recorded during the symptoms. Other options for evaluation include ECG monitoring and event recording, exercise ECG, implantable long-term monitors, and electrophysiological testing. Atrial premature beats (APBs) are usually benign and do not require further workup or delay in surgery. APBs may occur in healthy individuals or those with coronary artery disease, valvular heart disease, or cardiomyopathy. Frequent APBs (>100/day) may predict new occurrence of atrial fibrillation.
Clinical presentation of ventricular arrhythmias includes palpitations, skipped or extra beats, sustained palpitations, dyspnea, chest pain, dizziness, presyncope, syncope, and cardiac arrest. Patients with ventricular bigeminy or trigeminy can present with effective bradycardia and result in inaccurate estimation of the heart rate. Perioperative approach to patients with ventricular arrhythmias is presented in Figure 13-2.2,5,6
Perioperative Approach to Patients with Ventricular Arrhythmias
Several risk factors have been reported for the development of significant bradyarrhythmias intraoperatively during noncardiac surgery such as age >60 years, American Society of Anesthesia Class III or IV, preoperative heart rate <60 bpm or blood pressure <110/60 mm Hg, and use of beta-blockers or drugs that block the renin-angiotensin system. A few ...