Case Report:
A 73-year-old Caucasian woman, with past medical history significant for
hypertension, chronic obstructive pulmonary disease, chronic renal
disease, and non-ischemic cardiomyopathy (NYHA class II, ACC/AHA stage
C) who underwent a biventricular cardio-defibrillator (Medtronic- Viva
Quad, active fix leads, single coil) implantation in 12/2015 for primary
prevention. The following were the parameters during implantation: Right
atrium sensing 1.9mV, Impedance 684Ohms, pacing threshold 1.75V at
0.4ms; right ventricle sensing 6.9 mv, Impedance 551 Ohms, pacing
threshold 0.75V at 0.4ms, and left ventricle sensing 10.8mV, Impedance
475 Ohms, pacing threshold 2.25 V at 0.4ms, respectively.
Patient was lost to follow up since initial implantation. While
inpatient for elective right shoulder surgery at an outside facility
when her device was interrogated for syncope work up in January 2021,
reportedly all leads parameters (details unavailable) were normal,
without tachyarrhythmia or ICD therapies, however generator was noted
nearing elective replacement indicator. She was referred and seen by our
practice for further device management in March 2021.
During office visit, device implant site (left upper chest) showed no
signs of local infection, dehiscence, or trauma. Patient didn’t report
further syncopal events. A 12- lead electrocardiogram (EKG) in office
showed sinus rhythm with idioventricular conduction delay/left bundle
branch pattern with QRS duration >140ms (Fig 1). Device
interrogation office showed higher capture threshold for both right
atrial at 3.75V at 1.5ms, and left ventricle 2.75V at 1.5ms with
diaphragmatic stimulation at 4.5V leads, while right ventricular lead
parameters were noted to be normal. We received RRT alert within three
weeks of office visit. She was promptly scheduled for battery change.
Her most recent left ventricular ejection fraction (LVEF) was 35-40%
(improved from 25% at initial implant).
Her pre-op chest x-ray (CXR) (Fig 2 panel B) revealed migration of RA
and LV leads into the superior vena cava - right atrial junction. Leads
were noted coiled around, while generator was displaced caudally-
medially dhen compared to the original sub clavicular location (Fig 2,
Panel A). The RV lead, however, remained well positioned. After informed
consent, a mutual decision was made to proceed with leads
revision/extraction and re-implantation in the EP lab. We used
mechanical Evolution® Shortie RL (Cook Medical LLC, Bloomington, IN),
EZTM stylet (Philips, Andover, MA), and Bulldog™ Lead
extender (Cook Medical LLC, Bloomington, IN) to perform a complete
successful transvenous extraction of dislodged RA and LV leads. On gross
examination, both extracted leads showed no signs of fracture or
insulation break, except for RA lead which had adhesions at mid-segment
and dense calcifications at distal end. The original CRT-D generator was
replaced with single chamber ICD generator and connected to her original
normal functioning DF-4 right ventricle lead.