Michael Shapiro, D.O., Sam Hanon, M.D.,
Paul Schweitzer, M.D.
Department of Cardiology, Beth Israel
Medical Center, University Hospital and Manhattan Campus for the Albert
Einstein College of Medicine, New York, USA.
Address for correspondence:
Michael Shapiro, D.O., Beth Israel Medical Center, Department of Cardiology,
First Avenue at 16th Street, Dazian Building, 11th Floor, New York, NY,
10003. Email: shapiromi@rcn.com
Abstract
This article describes an interesting case of
automated implantable cardioverter defibrillator (AICD) extrusion fifteen
months after implantation. The case report is followed by a discussion
of the causes and treatment of skin erosion following pacemaker/AICD insertion.
Key words: pacemaker complication, skin erosion, extrusion
Case report
The patient is
a 65 year old man with a history of chronic renal insufficiency, dyslipidemia,
hypertension, peripheral arterial disease, and coronary artery disease status
post myocardial infarction in 1994. He was revascularized with 3-vessel
coronary artery bypass grafting on 3/12/02 after he developed unstable angina.
His post-operative course was complicated by a deep venous thrombosis. Treatment
was initiated with warfarin and the patient was subsequently discharged
from the hospital. He was readmitted three weeks later with mild shortness
of breath. A ventilation/perfusion scan was negative for pulmonary
embolism. However, while on telemetry, the patient had an episode of
non-sustained ventricular tachycardia. He underwent diagnostic electrophysiologic
testing at which time he was inducible for ventricular tachycardia.
On 4/2/02, an AICD was implanted. He was discharged without incident
and did well for over a year without any arrhythmic event requiring ICD
shock. One week prior to the current admission the patient noted a skin
tear over the AICD with protrusion of the device to the anterior chest wall.
He visited his cardiologist to evaluate the extrusion of the device at which
time he was immediately referred for hospital admission.
The patient admitted
to minimal skin tenderness over the site but denied bloody or purulent drainage,
fevers, chills, or malaise. His medications included metoprolol
XL 50 mg daily, aspirin 81 mg daily, clopidogrel 75 mg daily, atorvastatin
10 mg daily, isosorbide mononitrate 20 mg daily, and gabapentin 300 mg daily.
Social history, family history, and review of systems were non-contributory.
On physical examination,
the patient had a temperature of 97.8° F, blood pressure 122/78 mm Hg,
pulse 86 beats per minute and regular, and respiratory rate of 20 breaths
per minute. He was a well developed, well nourished male sitting comfortably
in no distress. Examination of his neck revealed no JVD at 30°,
normal carotid upstrokes without bruits, and no thyromegaly. His chest
was clear and heart examination revealed a non-displaced point of maximal
impulse with a normal apical impulse, normal S1 and S2
without an S3 or S4. His pulse was regular with
an apical 2/6 holosystolic murmur with radiation to the axilla. His
anterior chest wall revealed a well healed sternotomy scar with erythema
in the left supraclavicular area at the point where his AICD was extruding
from his skin without drainage (see Fig. 1 and Fig. 2). His
abdomen was obese but soft without hepatomegaly. Neurologically, he
was grossly intact. His lower extremities revealed no edema and distal
pulses were intact. His initial laboratory results were normal including
metabolic profile, complete blood count with differential, and coagulation
profile. His chest radiograph revealed clear lungs, normal heart size,
and a dual chamber pacemaker/defibrillator with leads in proper position.
His electrocardiogram (ECG) revealed a normal sinus rhythm with right bundle
branch block, left posterior fascicular block, and an old inferior infarct.
This ECG was unchanged from prior tracings. The patient was admitted
to the hospital and three sets of blood cultures were obtained. He was subsequently
started on vancomycin 1 g intravenously q 12h. The following day his device
was explanted and the pocket debrided. Blood cultures as well as cultures
from the device and surrounding skin and subcutaneous tissue revealed no
growth. He was continued on antibiotics and discharged from the hospital
without complications. The discharge plan was to replace the AICD at
a future date, upon healing of the operative site.
Figure
1. Photo of the patient depicting the erosion of the AICD through
the skin.
Figure 2.
Close up examination of AICD of same patient eroding through the skin.
Note upper right corner of subcutaneous pocket shows severe erythema with
signs of pre-erosion.
Discussion
This case illustrates
an unusually severe form of pacemaker/AICD skin erosion. This rare
complication has been previously described in the literature. However,
prior to the study performed by Kiviniemi et al,1
most of the existing data was based on information from the 1970s.2 This more recent investigation retrospectively
analyzed four hundred forty-six patients who received permanent pacemakers
and reported the complications noted during implantation or follow-up.
Pacemaker erosion was detected in 0.9% of the patients.
Two main culprits
have been implicated in the pathogenesis of pacemaker extrusion. First,
infection of the site can lead to skin erosion.3
Obviously, prevention of and monitoring for infection is paramount to averting
this process. DaCosta et al. performed a meta-analysis of antibiotic prophylaxis
for pacemaker implantation.4
They concluded that antibiotics administered during the peri-implant period
reduced the incidence of infective complications following pacemaker implantation,
including short-term pocket infection, skin erosion, or septicemia.
The other cause
of skin erosion is pressure necrosis of the overlying tissue and skin.3 Gross pacemaker extrusion is usually
signaled by a preceding period of “pre-erosion,” during which there is discomfort
and discoloration of thinning tissue tensely stretched over a protrusion
of the pacing apparatus (Fig. 2). Griffith et al. concluded
that if pacemaker erosion is not caused by infection it can be successfully
managed by ipsilateral re-implantation, a financially advantageous solution.5 Identification of pre-erosion allows salvage
of the pacing system, as the hardware can be repositioned under the pectoralis
muscle or in an abdominal location.
Risk factors for
skin erosion include factors related to the device itself as well as to
the implantation site. The mass and configuration of the pacemaker as well
as the need for extra hardware (e.g., lead adaptor) in the pocket may lead
to local tension and pressure necrosis. Additionally, precise surgical construction
of the pacemaker pocket is vital. A pocket of inadequate size or a paucity
of subcutaneous tissue may contribute to local complications. The pocket
plane should be created on the surface of the muscle since superficial pockets
lend themselves to erosion.6
If true erosion
occurs, the system is considered contaminated and current opinion favors
removal of the generator and leads. Extensive debridement of the pocket
and prolonged irrigation and antibiotic therapy may provide an alternate
option to removal in cases of both erosion and frank infection,7 but this approach is not generally preferred.
Attempts have been made to preserve the implanted leads by debriding locally
and severing the pacemaker leads while leaving them in situ. However, given
the relative safety and efficacy of percutaneous lead removal, complete
removal of the leads is the ideal approach if sterility is questioned.
References
1. Kiviniemi
MS, Pirnes MA, Eranen HJ, Kettunen RV, Hartikainen JE. Complications
related to permanent pacemaker therapy. Pacing & Clinical Electrophysiology.
1999;22(5):711-20.
2. Cohn JD, Santhanam R, Rosenbloom
MA, Thorson RF. Delayed pacemaker erosion due to electrode seal defects.
Annals of Thoracic Surgery. 1979;28:445-450.
3. Smyth NPD, Millette ML. Complications
of pacemaker implantation. In: Barold SS, ed. Modern Cardiac Pacing. Mount
Kisco, NY: Futura Publishing Co; 1985:257–304.
4. Da Costa A, Kirkorian
G, Cucherat M, Delahaye F, Chevalier P, Cerisier A, Isaaz K, Touboul P.
Antibiotic prophylaxis for permanent pacemaker implantation: a meta-analysis.
Circulation. 1998 May 12;97(18):1796-801.
5. Griffith MJ, Mounsey JP, Bexton
RS, Holden MP. Mechanical, but not infective, pacemaker erosion may be successfully
managed by re-implantation of pacemakers. Br Heart J. 1994;71:202–205.
6. Pavia
S, Wilkoff B. The management of surgical complications of pacemaker
and implantable cardioverter-defibrillators. Curr Opin Cardiol.
2000;16:66-71.
7.
Hurst
LM, Evans HB, Winale B, Klein GJ. The salvage of infected cardiac
pacemaker pockets using a closed irrigation system. Pacing & Clinical
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