More Is Not Always More: A Timely Reminder Why Not to Use Too Much Hardware

摘要

A healthy 79-year-old male with non-ischaemic cardiomyopathy underwent an implantable cardioverter defibrillator (ICD) insertion 7 years ago following presentation with a haemodynamically significant ventricular tachycardia. A 9 French dual coil ventricular and a 6 French atrial lead were inserted transvenously. While considering an upgrade to a biventricular device due to symptomatic heart failure, striking bilateral symmetrical varicosities over the chest and abdomen (Figure 1A and B), suggestive of superior vena cava (SVC) obstruction, were noted. Echocardiography showed severely impaired left ventricular systolic function. On questioning, he admitted to having a fuzzy head and dizziness when bending over. Chest X-ray showed normally positioned dual coil ICD from a lef infraclavicular approach (Figure 1C). Computed tomography venogram confirmed stenosis of the SVC (Figure 1D). SVC obstruction is a known entity (in up to 30% cases) in the context of bulky ICD leads. However, it remains asymptomatic and thus often goes unnoticed until the need for device upgrade with a new lead or extraction arises.1) Having said that, venous engorgement such as in our case is very rare. One of the common causes of stenosis at the right atrium (RA) - SVC junction is the SVC coil of a dual coil ICD. Superiority of dual, versus single coil leads, in terms of defibrillation efficacy remains to be proven.2) Moreover, the SVC coil increases lead complexity, cost, risk of lead failure, and lead removal.3) Also, in the absence of a bradycardia indication, the potential of an additional atrial lead to enhance arrhythmia discrimination, reduce inappropriate shocks, rate of hospitalization and mortality has not been borne out by scientific studies.4) A SVC coil induces not only wall adhesions, but also sclerotic reorganisation of the venous wall resulting in stenosis and obstruction.1).