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BACKGROUND Cardiac resynchronization therapy (CRT) implant procedures are often complex and prolonged, resulting in significant ionizing radiation (IR) exposure to the patient and operator. We report our early experience working with a novel sensor-based electromagnetic tracking system (MediGuide™, MDG, St. Jude Medical Inc., St. Paul, MN, USA), in terms of procedural IR exposure reduction. METHODS AND RESULTS Information regarding patient demographics, procedural details, procedural duration, and IR exposure were prospectively collected on 130 consecutive CRT procedures performed between January 2013 and January 2014. Sixty procedures were performed with MDG guidance, and 70 were performed without MDG guidance. Despite a nonsignificant trend toward shorter procedure duration with the use of MDG (120 minutes vs 138 minutes with non-MDG, P = 0.088), a 66% reduction in total IR exposure (median 769 μGray · m(2) vs 2,608 μGray · m(2), P 90% reduction in IR dose required to cannulate the coronary sinus (median 80 μGray · m(2) vs 922 μGray · m(2), P < 0.001), and to a lesser extent from a reduction in IR dose required for LV lead placement (median 330 μGray·m(2) vs 737 μGray · m(2), P = 0.059). In addition, a significant learning curve effect was observed with a significantly shorter procedural duration for the last 15 cases compared to the first 15 cases (median 98 minutes vs 175 minutes, P < 0.001). CONCLUSION The nonfluoroscopic MDG positioning system is associated with a dramatic reduction in exposure to IR during CRT implant procedures, with a 90% decrease in the IR dose required to cannulate the coronary sinus. A steep learning curve was quantified.

Background Radiation exposure is a major concern in cardiac device implantation, especially cardiac resynchronization therapy (CRT) procedures. The RadPad™ (Worldwide Innovations & Technologies, Inc., Kansas City, MO, USA), a radiation-attenuating adhesive drape, has been shown to be beneficial in several clinical settings involving fluoroscopy, but less is known about the actual benefits in CRT procedures. Methods Consecutive CRT implants performed with and without a RadPad™ drape over a 10-month period were analyzed. Two thermoluminescent dosimeters (TLDs) were attached to each implanting physician at several locations (adjacent to eyes, center abdomen [outside lead apron], left and right index fingers, and dorsum of the right foot). Results were corrected for background using control TLDs, and normalized to dose-area product (DAP). Results Thirty-six patients (31 male), 16 with and 20 without the RadPad™, were included in the study. No technical problems were caused by the presence of the radiation-absorbing drape. Time required to position the drape never exceeded 30 seconds, no acute skin reactions were noted, and no radiation-absorbing drape became displaced. Despite a trend toward longer fluoroscopy times and higher DAPs in the radiation-absorbing drape group, radiation exposure was significantly reduced: 65% in the case of the hands and body (P < 0.001), and 40% the eyes (P < 0.01). Conclusion The use of a radiation-absorbing drape results in a significant reduction in radiation dose to the implanting physician during CRT procedures. Not only is the dose to the hands reduced, but also the eye and body doses are significantly reduced. The routine use of radiation-absorbing drapes should be considered for all CRT implant procedures in the light of these findings.

The aim of this study was to evaluate whether steroid membrane leads can reduce pacing thresholds and thereby save energy as compared to nonsteroid membrane leads. The study was a random sample, double blind test consisting of 90 patients between 49-94 years of age admitted to seven hospitals in Europe for pacemaker implantation. The two leads compared in this study had contoured activated carbon tips covered with ion exchange membranes. The leads were identical except that 30 micrograms of dexamethasone was dissolved in the ion exchange membrane of one of the leads. Normal lead implant procedures were used. Follow-up procedures were conducted at 2 weeks and 1, 3, 6, and 12 months after lead implantation. The pulse generator was programmed to an amplitude of 2.5 or 5 V and a duration of 0.5 msec. The stimulation threshold was measured using the VARIO function. The threshold was measured a total of three times in order to determine the presence of microdislocations. At the 2- and 4-week follow-ups, the stimulation threshold was significantly lower for the steroid leads than for the membrane leads without steroid (0.54 +/- 0.19 vs 0.76 +/- 0.25 V, P = 0.0005; and 0.59 +/- 0.19 vs 0.74 +/- 0.26 V, P = 0.005), but after 3 months, the threshold values were almost the same for both leads.