William J. Bonney

Impact of Cardiac Devices on the Quality of Life in Pediatric Patients

Background— Cardiac rhythm devices are increasingly used in the pediatric population, although their impact on quality of life (QOL) is poorly understood. The purpose of this study was to compare (QOL) scores among pediatric device patients, healthy controls, and congenital heart disease (CHD) patients and determine the key drivers of QOL in pediatric device patients. Methods and Results— Multicenter, cross-sectional study at 8 pediatric centers of subjects aged 8 to 18 years with either a pacemaker or defibrillator was carried out. Patient–parent pairs completed the Pediatric Quality of Life Inventory and Pediatric Cardiac Quality of Life Inventory. QOL outcomes in device patients were compared with healthy controls and patients with various forms of CHD. Structural equation modeling was used to test for differences in Pediatric Cardiac Quality of Life Inventory scores among (1) device type, (2) presence of CHD, and (3) hypothesized key drivers of QOL. One hundred seventy-three patient–parent pairs (40 defibrillators/133 pacemakers) were included. Compared with healthy controls, patients with devices and their parents reported significantly lower Pediatric Quality of Life Inventory scoring. Similarly, compared with patients with mild forms of CHD, parents and patients with devices reported significantly lower Pediatric Cardiac Quality of Life Inventory scores and were similar to patients with more severe CHD. Key drivers of patient QOL were presence of implantable cardioverter-defibrillator and CHD. For patients, self-perception was a key driver of lower QOL, whereas for parents behavioral issues were associated with lower QOL. Conclusions— Patient QOL is significantly affected by the presence of cardiac rhythm devices. Whether these effects can be mitigated through the use of psychotherapy needs to be assessed.

Implantable cardioverter-defibrillator lead failure in children and young adults: a matter of lead diameter or lead design?

OBJECTIVESnThis study aimed to investigate the impact of lead diameter and design on implantable cardioverter-defibrillator (ICD) lead survival in children and young adults.nnnBACKGROUNDnRecent reports have called attention to high rates of lead failure in adults with small-diameter ICD leads, but data in the pediatric population is limited.nnnMETHODSnWe reviewed lead performance in consecutive subjects ≤30 years with transvenous right ventricular ICD leads implanted at our center between January 1995 and October 2011. Lead failure was defined as fracture, perforation, or sensing failure necessitating revision.nnnRESULTSnA total of 120 ICD leads were implanted in 101 patients at a mean age of 15.5 ± 4.9 years. There were 47 small-diameter (≤8-F) and 73 standard-diameter (>8-F) leads. During a median follow-up of 28.7 months (interquartile range: 14.4 to 59.2 months), there were 25 lead failures (21% prevalence), with an incidence of 5.6%/year (95% confidence interval: 3.4 to 7.8). Sprint Fidelis (SF) (Medtronic, Inc., Minneapolis, Minnesota) leads had lower 3-year (69% vs. 92%, p < 0.01) and 5-year (44% vs. 86%, p < 0.01) survival probabilities than standard-diameter leads. In multivariate Cox regression, SF design conferred the greatest hazard ratio for lead failure (hazard ratio: 4.42, 95% confidence interval: 1.73 to 11.29, p < 0.01). Age and linear growth were not significantly associated with lead failure.nnnCONCLUSIONSnIn this single-center pediatric study that evaluated lead diameter, lead design, and patient factors, the SF design conferred the highest risk of lead failure, suggesting that design rather than diameter is the critical issue in ICD lead performance.

Junctional Tachycardia in a Child with Lyme Carditis

A 3-year-old girl presented with fatigue, fever, and rash. Tachycardia was noted and an ECG showed junctional tachycardia. Lyme titers were positive and the arrhythmia resolved with intravenous ceftriaxone.

Cardiac Ischemia, Injury, and Infarction

The electrocardiogram (ECG) is an irreplaceable diagnostic test in the evaluation of suspected myocardial injury. While children with structurally normal hearts are far less likely than adults to have acute coronary syndromes or true ischemic injury, it is not unusual for a child to present with chest pain in a setting that cardiac ischemia needs to be ruled out. Along with a careful history and exam, the ECG is an essential part of the workup for a child with acute chest pain. In otherwise healthy children without a history of congenital heart disease or cardiomyopathy, cardiac ischemia is exceedingly rare. This chapter provides a valuable guide for detecting cardiac ischemia, injury, and infarction in the pediatric population.

Heart Rate and Rhythm Disturbances

Few sounds evoke a feeling of life and vitality more than the regular “thump-thump” of a human heartbeat. When a person is resuscitated from cardiac arrest and their pulse returns, the regular beeping of a bedside monitor is a calming sound that allows everyone in the room to breathe a sigh of relief. Conversely, abnormal heart rhythms may send a wave of anxiety through the bodies of medical providers, particularly those who lack a sense of familiarity with arrhythmias. With a little practice and by following a methodical step-by-step system, one can learn to recognize the various abnormal heart rhythms that are commonly encountered in pediatric patients.

Atrioventricular Conduction Abnormalities: Preexcitation, Heart Block, and Other Ventricular Conduction Abnormalities

Each cardiac impulse originates in the sinus node with the ultimate objective of producing normal atrial and then ventricular contractions. Each heartbeat traverses the atrial tissue, AV node, bundle of His, and right and left bundle branches on the way to smaller branches in the His-Purkinje system and ultimately ventricular myocardium. Abnormalities in any of these structures produce varying degrees of atrioventricular conduction or heart block. This chapter reviews these disturbances to distinguish benign observations from pathological aberrations of cardiac electrical conduction.