Pacemaker Implantation — Procedure Guide, Recovery & Risks | MyMedicPlus

Pacemaker implantation is a cardiac device procedure in which a small battery-powered pulse generator is surgically placed in a subcutaneous pocket beneath the skin of the upper chest, with one, two, or three thin insulated electrical leads (wires) threaded through a vein into the chambers of the heart. The device continuously monitors the heart's intrinsic electrical activity and delivers precisely timed low-energy electrical impulses to stimulate cardiac contraction when the heart's own conduction system produces inadequate or absent signals.

The cardiac conduction system normally generates impulses from the sinoatrial (SA) node in the right atrium, which propagate through the atrioventricular (AV) node into the His-Purkinje system, depolarising the ventricular myocardium in a coordinated wave. Disease of the SA node (sick sinus syndrome) or the AV node and bundle branches (heart block) disrupts this pathway, causing bradycardia -- abnormally slow heart rate -- with symptoms of fatigue, dizziness, presyncope, or syncope (loss of consciousness).

Pacemakers are classified by the NBG code describing the chambers paced, chambers sensed, and response to sensed events. A single-chamber ventricular pacemaker (VVI) paces the right ventricle and inhibits itself when intrinsic ventricular activity is detected. A dual-chamber pacemaker (DDD) paces and senses both atrium and ventricle, maintaining the natural AV synchrony that optimises cardiac output. Cardiac resynchronisation therapy pacemakers (CRT-P, biventricular pacing) add a third left ventricular lead via the coronary sinus to resynchronise ventricular contraction in heart failure patients with electrical dyssynchrony. Leadless pacemakers are miniaturised devices implanted directly into the right ventricular myocardium transcatheterly via the femoral vein, eliminating the conventional lead and pocket system and their associated complication classes.

All modern pacemakers include rate-responsive sensors (accelerometers) that increase pacing rate with physical activity, remote monitoring capability via bedside transmitters, and MR-conditional design allowing most MRI scans.

Permanent pacemaker implantation is indicated for symptomatic bradycardia caused by sick sinus syndrome (sinus arrest, sinoatrial block, tachy-brady syndrome) or atrioventricular conduction disease (second-degree Mobitz II AV block, third-degree complete AV block, or acquired left bundle branch block with syncope). Chronotropic incompetence — failure of heart rate to rise appropriately with exercise causing significant functional limitation — also qualifies. Indications extend to post-procedural heart block following TAVI, cardiac surgery, or catheter ablation that damages the conduction system. Cardiac resynchronisation therapy (CRT) pacemakers are implanted in heart failure patients with reduced ejection fraction (under 35%) and LBBB with QRS duration greater than 150 ms. Contraindications include active systemic or pocket-site infection, life expectancy under 1 year from non-cardiac causes, and patient refusal following detailed counselling about risks and alternatives.

Pacemaker implantation is performed in a cardiac catheterisation laboratory or electrophysiology suite equipped with fluoroscopic X-ray guidance, continuous ECG monitoring, and resuscitation equipment. The procedure takes 1-2 hours under local anaesthesia with conscious sedation.

Pre-operative preparation: The infraclavicular area is surgically prepared with chlorhexidine and draped. IV access is established in the opposite arm. Cefazolin 2 g IV is given 30-60 minutes before incision. Anticoagulation is managed per the team's protocol -- warfarin is usually continued if the INR is therapeutic, as bridging increases haematoma rates without reducing thromboembolism. DOACs are typically held 24-48 hours before.

Anaesthesia: Local anaesthetic (lidocaine 1-2% with adrenaline) is infiltrated subcutaneously and into the pectoral fascia. Conscious sedation with midazolam and fentanyl provides anxiolysis and analgesia while maintaining patient cooperation.

Venous access: The cephalic vein is accessed by surgical cut-down in the deltopectoral groove (eliminating pneumothorax risk), or the subclavian or axillary vein is punctured under fluoroscopic or ultrasound guidance. One introducer sheath is placed per lead required.

Lead placement: The ventricular lead is advanced under fluoroscopy through the right atrium, across the tricuspid valve, and screwed or wedged into the right ventricular septum or apex. His-bundle or left bundle branch area pacing sites provide more physiological ventricular activation at specialist centres. For dual-chamber pacing, an atrial lead is placed in the right atrial appendage. Lead pacing threshold, sensing amplitude, and impedance are measured to confirm satisfactory electrical contact. For CRT, a third lead is advanced through the coronary sinus into a lateral or posterolateral cardiac vein -- the most technically demanding step.

Pulse generator pocket and closure: A prepectoral subcutaneous pocket is created by blunt dissection deep to the subcutaneous fat and superficial to the pectoralis major fascia. The leads are connected to the pulse generator, which is seated in the pocket with appropriate lead redundancy. The pocket is irrigated with antibiotic solution and closed in layers with absorbable sutures.

Post-procedure: A chest radiograph confirms lead positions and excludes pneumothorax. The device is programmed to appropriate initial settings before the patient leaves the procedure room. An ECG records the paced rhythm confirming capture.

Pacemaker implantation is highly effective, resolving bradycardia-related symptoms in over 95% of patients. Modern devices last 7–15 years depending on pacing frequency before battery replacement (generator change) is needed. Quality of life, exercise tolerance, and survival all improve significantly after pacing for symptomatic bradycardia. Remote monitoring (Carelink, MerlinNET, LATITUDE) allows continuous telemonitoring with automatic alerts for arrhythmia events, pacing threshold changes, or lead issues, reducing the need for in-person clinic visits. Dual-chamber devices coordinate atrial and ventricular pacing to maintain physiological AV synchrony, preserving cardiac output better than single-chamber ventricular pacing. Physiological rate-adaptive pacing (VVIR, DDDR modes) adjusts pacing rate in response to physical activity sensors, mimicking normal chronotropic response during exertion in patients with chronotropic incompetence. Pacemaker therapy has been proven to reduce syncopal episodes and sudden death risk in patients with high-degree AV block.

Complications occur in approximately 3–5% of implants. These include pneumothorax (air around the lung from venous access, 1%), lead dislodgement requiring repositioning (1–2%), wound haematoma, pocket infection (1%), cardiac perforation (rare), and lead fracture over time. Modern pacemakers are MRI-conditional rather than MRI-safe — patients should carry their device identification card at all times and inform radiology staff before any imaging. Electromagnetic interference from industrial equipment, certain welding equipment, and some medical devices (electrosurgery, transcutaneous electrical nerve stimulation) can temporarily affect sensing. Pacemaker syndrome — fatigue, dyspnoea, and hypotension from loss of AV synchrony in single-chamber ventricular pacing — may require upgrade to dual-chamber device. Twiddler syndrome — patient manipulation of the generator in the pocket causing lead coiling and dislodgement — is prevented by appropriate pocket sizing and patient education.

Patients remain in hospital for 24–48 hours for rhythm monitoring and wound checks. The arm on the implant side must not be raised above shoulder level or involved in heavy activity for 4–6 weeks to allow leads to fix into the heart muscle. Wound care involves keeping the site dry for 5–7 days. A pacemaker device check is performed at 6 weeks to programme optimal settings. Long-term device monitoring via clinic review or remote monitoring every 6–12 months ensures battery longevity assessment and lead integrity checking. Patients are given a device identification card and registered with the national pacemaker registry. Activity restrictions including avoidance of contact sports and heavy overhead lifting on the implant side are maintained long-term. Patients undergoing dental or surgical procedures should receive antibiotic prophylaxis if device infection risk is elevated.