EnSite NavX mapping system guided implantation of a dual-chamber permanent pacemaker in a 41-year-old pregnant woman with a 4-year follow-up.

BACKGROUND: X-ray fluoroscopy has been the primary cardiac imaging modality in permanent pacemaker implantation (PPI) operations, but it inevitably results in radiation exposure for both operators and patients. Fluoroscopy is considered a contraindication, especially in certain circumstances, such as gestation, during which the fetus is most sensitive to radiation exposure. Therefore, measures to avoid radiation exposure are necessary, and a more safe and feasible approach is needed for this procedure. Since the EnSite NavX mapping system (ENMS) can create the required geometric contours of those relevant cardiac structures and chambers, it can be used as an alternative to X-ray fluoroscopy in PPI. In addition, because the displacement of atrial leads is a common complication of PPI, lead displacement may occur more readily without fluoroscopic guidance. Therefore, reliable measures are required to prevent leads from displacement. CASE INTRODUCTION: A 41-year-old woman at the 15th week of gestation was referred to our department with recurrent episodes of syncope and amaurosis fugax for 2 years. Holter monitoring showed sinus rhythm, Mobitz Type II atrioventricular block and high-grade atrioventricular block with ventricular arrest up to 4945 ms. A dual-chamber PPI was performed successfully for the patient under the guidance of the ENMS instead of fluoroscopy. Displacement of atrial lead was effectively avoided by bending the top of atrial lead before implantation and making it a U-shape during operation, which left space for possible subsequent external pulling stress. CONCLUSIONS: For PPI, ENMS is a feasible and reliable alternative to traditional X-ray fluoroscopy, especially when performing operations on pregnant patients. By bending the top of the active-fixation atrial lead into a U-shape during operation, the displacement of atrial lead may be avoided.