Radiographic Predictors of Lead Conductor Fracture

Abstract

All 23 adult Canadian implantable cardioverter defibrillator implantation centers were surveyed to identify centers that routinely capture anteroposterior or posteroanterior (AP) and lateral x-rays within 2 weeks of implant and at least AP x-rays at the time of fracture identification. Eight of those centers collected those x-rays routinely. All eligible centers agreed to participate in the study. Centers were © 2014 American Heart Association, Inc. Original ArticleBackground-Lead fracture is a limiting factor in high voltage lead durability. Fractures noted with the Medtronic Fidelis leads provide an opportunity to examine factors captured on implant chest x-ray that correlate with risk for lead conductor fracture. We evaluated contributory factors in a large population of fractures. Methods and Results-We conducted a retrospective case-control study at 8 Canadian centers that routinely capture anterior posterior and lateral chest x-rays within 2 weeks of implant. Cases were patients that experienced confirmed Medtronic Fidelis 6949 lead fracture based on standard definitions, matched one-to-one to controls for date of implant, sex, and age with normally functioning Fidelis leads from the same center. Select chart data and x-rays were collected for all patients. Radiographic measurements by ≥2 individuals per case/control were blinded to patient status. The data were analyzed using a time to failure multivariable Cox proportional hazards model with stratification for each matched pair. X-ray pairs from 111 fracture patients were compared with 111 controls (age 61.5±12.8 years, 75% male, 221 model 6949 leads). Six parameters included in the statistical analysis were significantly associated with risk of fracture, including slack/ tortuosity measures, pulse generator and superior vena cava coil location, and angle of lead exit from the pocket. Conclusions-Pocket, intravascular and intracardiac lead characteristics on x-ray correlate with risk of lead conductor fracture. These observations may be useful to direct implant technique to optimize lead durability. Validation in larger populations and other lead models may inform the application of these results. (Circ Arrhythm Electrophysiol.

Axillary vein puncture using fluoroscopic landmarks: a safe and effective approach for implantable cardioverter defibrillator leads

“…Instead, the use of body surface of the second rib as landmark offered a significantly higher (100 %) success rate and a more lateral approach avoiding potential lead entrapment between the clavicle and the first rib, a cause of lead failure during follow-up [10]. Recently, Krahn, in a retrospective case-control study of 133 patients with Fidelis lead fractures, found that a more lateral vein access point is associated with a lower fracture risk [27]. In our study, in four or five patients with a Bfirst rib approach^failure due to abnormal vein course, the venography showed that axillary vein crossed the body surface of the second rib.…”

Intermittent Pacemaker Malfunction Caused by Continuous Compression of the Lead by the Clavicle (Subclavian Crush Syndrome)

“…The incidence of subclavian crush syndrome can also be predicted by several angiographic parameters, such as pocket, intravascular and intracardiac lead characteristics [ 10 ] .…”

Caudal fluoroscopy to guide venous access for pacemaker device implantation: should this now be standard practice?

“…Furthermore, in using the PA approach to puncture the subclavian vein over the first rib, many operators will chose a steep angle (perpendicular to the chest wall) to minimise any drift in the superior/inferior directions, which could lead to a puncture beyond the boundaries of the first rib and hence a pneumothorax. However, accessing the subclavian vein at a perpendicular angle can theoretically increase flexion stress on the lead 6. The caudal view improves visualisation of the first rib and lung borders (figure 1C) and permits a shallower angle of entry into the subclavian vein theoretically reducing the risk of flexion damage to the lead.…”