Dual‑chamber pacemakers for symptomatic bradycardia due to sick sinus syndrome without atrioventricular block

Dual‑chamber pacemakers are small battery‑driven devices implanted in the chest with pacing leads inserted in the right atrium and ventricle. The pacing leads have sensors that detect the natural heartbeat and send that information to a small computer in the pacemaker. The pacemaker uses this data to send signals back to the heart to help it beat regularly. There are several different types of dual‑chamber pacemaker depending on whether they inhibit or trigger heart beats (in response to sensed electrical activity in the heart) and whether they are rate responsive (in which the pacing rate varies according to physical activity).

Dual‑chamber pacemakers may be associated with a number of adverse reactions. The need for an additional lead in dual‑ compared with single‑chamber pacemakers might lead to an associated increased risk of complications, such as lead displacement, puncture of the lung when placing the leads and infection of the pacemaker pocket or the leads. Complications arising after pacemaker implantation may include dysfunction of the pacemaker or of the leads (that is, failure to pace or sense appropriately), infection or erosion of the pacemaker site or its leads and the development of pacemaker syndrome, stroke, heart failure or atrial fibrillation. Re‑operation may be needed as a result of a complication or end‑of‑battery life. The complication rate associated with a re‑operation to remove or replace leads is higher than that associated with initial implantation. Battery replacement has a very low complication rate when the leads do not need to be removed or replaced.

The acquisition cost of pacemakers depends on the particular model. The Association of British Healthcare Industries estimates an average cost of dual‑chamber pacemaker devices of £1,265, and for single‑chamber atrial pacemaker devices a price of £718. Costs may vary in different settings because of negotiated procurement discounts.