What are the key indications for referring a patient for pacemaker or ICD implantation in primary care?

Key indications for referring a patient for pacemaker implantation in primary care include symptomatic bradycardia due to sinus node dysfunction or atrioventricular (AV) block, particularly when associated with syncope, presyncope, or heart failure symptoms despite optimal medical therapy ¹. Patients with high-grade AV block or complete heart block require urgent referral for pacing to prevent sudden cardiac death and improve symptoms ¹ (Rao and Bennett, 2022).

For implantable cardioverter-defibrillator (ICD) implantation referral, primary care should consider patients with heart failure and reduced left ventricular ejection fraction (LVEF ≤35%) despite at least 3 months of optimal medical therapy, especially those with ischaemic or non-ischaemic cardiomyopathy, as these patients are at increased risk of sudden cardiac death and benefit from ICD for primary prevention ¹ (Barakat et al., 2017; Jaiswal et al., 2024). Additionally, patients with a history of sustained ventricular tachycardia or ventricular fibrillation, or survivors of sudden cardiac arrest, should be referred for ICD evaluation as secondary prevention ¹ (Rao and Bennett, 2022).

In summary, primary care referral for pacemaker is primarily indicated for symptomatic bradyarrhythmias and conduction blocks, while ICD referral is indicated for patients with significant systolic dysfunction at risk of malignant ventricular arrhythmias or with prior life-threatening arrhythmias. These recommendations align with NICE guidelines on chronic heart failure and device therapy ¹ and are supported by meta-analyses demonstrating mortality benefit in both ischaemic and non-ischaemic cardiomyopathy populations (Barakat et al., 2017; Jaiswal et al., 2024).