Skip to Main Content

++

Pacemaker and defibrillator management is the subject of comprehensive reviews.1 In the author's experience with 2760 procedures, 23% of pacemaker recipients and 5% of implantable cardioverter defibrillator (ICD) recipients were octogenarians. The incidence of pacemaker insertion in patients older than 75 was 2.6% in a recent survey. The efficacy and cost-effectiveness of pacemakers are widely accepted, but the appropriate role for ICD insertion and biventricular pacing in older patients is still in evolution. Pacemaker and ICD technology is now applicable across the entire span of human age, with pacing for heart failure and ICD prophylaxis against lethal arrhythmias recent frontiers. Electrophysiologists now dominate these areas, reflecting decreased interest by thoracic surgeons and cardiology referrals. However, thoracic surgeons must maintain skills as implanters and consultants for complex or complicated cases. This chapter reviews practical information related to pacemaker and ICD insertion and management.

++

Device Description

++

A permanent pacemaker or ICD consists of leads2 and a generator. The generator contains a battery, a telemetry antenna, and integrated circuits. ICDs also include capacitors that store energy for high-output shocks. The power source is generally lithium iodide, but rechargeable and nuclear batteries have been used. The integrated circuits include programmable microprocessors, oscillators, amplifiers, and sensing circuits.3 The integrated circuits employ CMOS (complementary metal-oxide semiconductor) technology, which is subject to damage by ionizing radiation.4 Current pacemakers and ICDS monitor and report the status of internal components, external connections, programmed settings, recent activity, and notable arrhythmias. Unfortunately, each programmer controls only the devices of its manufacturer.

++

History

++

Early cardiac surgery was complicated by lethal iatrogenic heart block. Transthoracic pacing with Zoll cutaneous electrodes provided a solution.5 Percutaneous endocardial pacing (1959)6 and "permanent" pacemakers using epicardial electrodes (1960)7 followed. Advances in bioengineering and technology have dramatically improved the quality of life for recipients. Persistent problems include lead durability, inflammatory responses to pacemaker materials, infection, device size, programmer compatibility, and expense. Development of resynchronization therapy has made coronary sinus lead insertion an important technical skill.

++

Anatomy of Surgical Heart Block

++

The conduction system is vulnerable to injury during heart surgery. Complete heart block can result from suture placement during aortic, mitral, or tricuspid valve surgery or during closure of septal defects or during myotomy for idiopathic hypertrophic subaortic stenosis. These lesions are illustrated in Fig. 59-1. Infarction of the conduction system or inadequate myocardial protection can also result in surgical heart block.

++
Figure 59-1
Graphic Jump Location

Anatomy of iatrogenic complete heart block. (A) His bundle and cardiac structures. Sites of injury are circled. (B) The His bundle in the ventricular septum, below the noncoronary-right coronary aortic commissure. (C,D) During mitral surgery, the His bundle is on the ventricular septum anteromedial to the posterior commissure and right ...

Want remote access to your institution's subscription?

Sign in to your MyAccess profile while you are actively authenticated on this site via your institution (you will be able to verify this by looking at the top right corner of the screen - if you see your institution's name, you are authenticated). Once logged in to your MyAccess profile, you will be able to access your institution's subscription for 90 days from any location. You must be logged in while authenticated at least once every 90 days to maintain this remote access.

Ok

About MyAccess

If your institution subscribes to this resource, and you don't have a MyAccess profile, please contact your library's reference desk for information on how to gain access to this resource from off-campus.

Subscription Options

AccessSurgery Full Site: One-Year Subscription

Connect to the full suite of AccessSurgery content and resources including more than 160 instructional videos, 16,000+ high-quality images, interactive board review, 20+ textbooks, and more.

$995 USD
Buy Now

Pay Per View: Timed Access to all of AccessSurgery

24 Hour Subscription $34.95

Buy Now

48 Hour Subscription $54.95

Buy Now

Pop-up div Successfully Displayed

This div only appears when the trigger link is hovered over. Otherwise it is hidden from view.