Technical aspects of pacing in adult and pediatric congenital heart disease.

As intuitive as it might appear, it must be remembered that children are not little adults and congenital heart defects do not equate to normal cardiac anatomy. In addition, repaired congenital heart defects in adults (ACHD) might also not equate to normal anatomy. In each of these clinical situations, pacemaker device therapy may dramatically differ from most of the published information available in the field of internal medicine cardiology. Since there are now more patients with structural congenital heart defects over than under the age of 21 years, all present and future generations of pacemaker implanters need to recognize the plethora of anatomical and structural nuances potentially associated with the implantation of device therapy in this continually expanding patient population. Fortunately, advances in pacemaker and lead technology over the past 20 years, which now permit precise implantation at selective endocardial sites other than the right ventricular apex or atrial appendage and improved epicardial leads, have greatly facilitated optimization of pacing therapy. Whereas past interests have focused on lead performance issues such as dislodgement, fractures, and exit block, improvements in lead design technologies now permit more interest in maintaining or improving paced myocardial function by optimizing lead placement at alternate or more select sites. This article reviews recent applications and future directions of these pacing technologies and emphasizes differences among patients with congenital heart defects.