Dysrhythmia Management and Pacing

Cardiac dysrhythmias are disturbances in the rate, rhythm, or conduction of the heartbeat, ranging from benign extra beats to life-threatening ventricular arrhythmias. Their management includes monitoring, medication, electrical therapies, and implanted devices such as pacemakers and defibrillators. For nurses, rhythm interpretation, telemetry monitoring, and care of patients with cardiac devices are core cardiovascular skills.

Definition

Cardiac arrhythmias (MeSH descriptor Arrhythmias, Cardiac) are abnormalities of cardiac rate, rhythm, or electrical conduction, classified broadly into bradyarrhythmias and tachyarrhythmias and into supraventricular and ventricular origins; pacing refers to electrical stimulation of the heart, delivered temporarily or by an implanted pacemaker, to maintain an adequate rhythm.

Scope

This topic covers the major arrhythmia categories, the conduction-system mechanisms that produce them, and the device and guideline framework for management, including pacing and defibrillation. It treats the nursing relevance of monitoring and device care in reference terms, without prescribing individualized assessment or therapy.

Core questions

• How are arrhythmias categorised by origin and by rate?
• What conduction mechanisms produce common arrhythmias such as atrial fibrillation?
• How do pacemakers and implantable defibrillators fit within rhythm management?

Key concepts

• Supraventricular versus ventricular arrhythmias
• Bradyarrhythmia and tachyarrhythmia
• Atrial fibrillation and stroke risk
• Re-entry and abnormal automaticity
• Telemetry and electrocardiographic monitoring
• Cardiac pacing (pacemakers)
• Implantable cardioverter-defibrillators and sudden cardiac death prevention

Mechanisms

Normal heart rhythm depends on orderly impulse generation in the sinoatrial node and conduction through the atrioventricular node and His-Purkinje system. Arrhythmias arise when this is disrupted: abnormal or enhanced automaticity, triggered activity, or re-entrant circuits produce ectopic or rapid rhythms, while conduction block produces slow rhythms. Atrial fibrillation, the most common sustained arrhythmia, involves disorganised atrial electrical activity and carries a risk of thromboembolism (Hindricks et al., 2020). Ventricular arrhythmias can degenerate into fibrillation and cause sudden cardiac death, which is the rationale for implantable defibrillators (Al-Khatib et al., 2018). Pacing supplies electrical stimulation when intrinsic conduction is inadequate.

Clinical relevance

Arrhythmias are common reasons for monitoring and admission, and nurses are central to telemetry interpretation, recognition of dangerous rhythms, and care of patients with pacemakers and defibrillators. This entry describes the conditions and the device and guideline framework around them for reference and education and is not a basis for individualized diagnosis or treatment.

Epidemiology

Atrial fibrillation is the most common sustained arrhythmia and rises sharply in prevalence with age, carrying a substantial stroke burden; ventricular arrhythmias are a leading mechanism of sudden cardiac death (Hindricks et al., 2020; Al-Khatib et al., 2018).

Evidence & guidelines

Management is structured by guidelines including the 2020 ESC atrial fibrillation guidelines and the 2017 AHA/ACC/HRS guideline on ventricular arrhythmias and sudden-death prevention, which define diagnosis, risk stratification, and indications for device therapy (Hindricks et al., 2020; Al-Khatib et al., 2018). Expert consensus statements address the genetic basis of inherited arrhythmia syndromes (Wilde et al., 2022).

Seminal works

• hindricks-2020
• alkhatib-2018

Frequently asked questions

What is the most common cardiac arrhythmia?

Atrial fibrillation is the most common sustained arrhythmia; its prevalence rises with age and it is associated with an increased risk of stroke, as set out in current ESC guidelines.

What is the difference between a pacemaker and an implantable defibrillator?

A pacemaker delivers electrical impulses to maintain an adequate heart rate when intrinsic conduction is too slow, whereas an implantable cardioverter-defibrillator additionally detects dangerous fast ventricular rhythms and can deliver a shock to terminate them.