“Ratchet” syndrome, another etiology for pacemaker lead dislodgement: A case report

Our patient was diagnosed with familial 2:1 atrioventricularblock and had initially presented with bradycardia and as-sociated shortness of breath and decreased exercise toler-ance at the age of 7. She subsequently underwent an epi-cardial DDD pacemaker implantation with immediateimprovement in symptoms.At age 11, she was noted to have loss of sensing andcapture due to a ventricular lead fracture. Additionally, thegenerator was approaching elective replacement time. Sheunderwent placement of a transvenous DDDR pacemaker.The pocket was created beneath the pectoralis muscle. Us-ing a venogram as a “roadmap”, the axillary vein wasentered at two separate sites through the pocket. Medtronic3830 active ﬁxation leads were placed into the mid septalarea of the right ventricle, and near the right atrial append-age. Additional slack was advanced on both the atrial andventricular lead to allow for growth. Pacing and sensingthresholds were established and adequate values were ob-tained. The proximal end of the lead was secured using thesewing sleeve with 2-0 Prolene (monoﬁlament nonabsorb-able suture) and was then attached to the underlying fascia.The pacemaker generator was placed in the pocket withleads attached. With pacemaker interrogation appropriatepacemaker function was noted without diaphragmatic stim-ulation. The pacemaker was sutured to the underlying fasciawithin the pocket with the 2-0 Prolene, and the pocket wasclosed in three layers.A chest x-ray the following morning showed stable leadplacement with appropriate slack of the lead within theventricle (Figure 1). The pacemaker interrogation prior todischarge demonstrated appropriate pacemaker and leadfunction and a 24-hour ambulatory ECG monitor was es-sentially unremarkable. A sling was worn for the next 3–4days and the patient was instructed not to raise her armabove her shoulder for the next 6 weeks.Five weeks after implantation, the patient noted that herheart rate was low and she experienced twitching of her armthat seemed to coincide with her pacemaker rate. No othersymptoms were reported. She and her mother indicated shehad been compliant with the arm restrictions. She deniedmanipulating the pacemaker area, the device, or the lead.She stated that the incision had itched, but she had been verycareful not to scratch “hard”. Axillary and pocket stimula-tion were noted on physical exam. Device interrogationdemonstrated complete lack of sensing and pacing withnormal lead impedance values. The chest x-ray demonstratedthat the lead had retracted completely out of the heart andappeared to be wrapped around the pacemaker (Figure 2). Thetip of the ventricular lead was at the anterior axillary linewhile the atrial lead remained in place.The ventricular lead was removed and a new lead wasplaced in the manner previously described. During the ven-tricular lead replacement, the sewing sleeve was noted to bein the same position as originally placed, but with the leadpulled completely out of the sleeve. There were no visibleabnormalities of the lead. Since replacement of the lead, nosubsequent lead problems have been found, and the pace-maker system was functioning normally at both her one andthree month follow-up visits.