Case presentation
A 76-year-old man with history of ischemic cardiomyopathy and paroxysmal
atrial fibrillation who underwent a Dual-Chamber Medtronic Implantable
Cardioverter-Defibrillator (ICD) placement 6 years earlier in an outside
facility presented to the emergency room with worsening shortness of
breath. Initial workup in the emergency room revealed acute on chronic
combined congestive heart failure. An AP chest X-ray film showed
cardiomegaly with pulmonary vascular congestion and satisfactory ICD
lead position (Figure 2 ). No lateral view was obtained at the
time.
Bedside Echo showed severely reduced left ventricular systolic function
with dilated right ventricle and moderate to severe pulmonary
hypertension. Surprisingly, the ICD lead was clearly going from the left
atrium through the mitral valve to the left ventricular cavity
(Figure 3, 4 and 5 ). A lateral chest x-ray view revealed that
the ICD shock lead tip is directed posteriorly, indicating its presence
in the left ventricular cavity (Figure 6 ). A transesophageal
echocardiogram showed the ICD lead went from the superior vena cava to
the right atrium, crossing through a small sinus venous atrial septal
defect to the left atrium, and into the left ventricular cavity via the
mitral valve. Luckily, the patient was on chronic anticoagulant because
of chronic atrial fibrillation, so no thromboembolic complications were
reported. Interestingly enough, the patient had 2 prior trans-thoracic
echocardiograms that were interpreted by the same cardiologist without
mention of abnormal ICD lead placement.
Because extraction of a chronically implanted ICD lead carries a high
risk of major cardiovascular complications (2 to 4%) including vascular
injury, cardiac perforation resulting in cardiac tamponade, and
occasionally thromboembolic complications or even death, and because the
patient was chronically anticoagulated, the decision is made to continue
conservative management.