Introduction:
Subcutaneous ICD (S-ICD) implantation is a viable alternative to transvenous ICD implantation in patients without a pacing indication. The S-ICD lead is placed near the sternum. The safety of S-ICD implantation and risk for inappropriate shocks is uncertain in patients with prior sternotomy.
Methods:
This single-center retrospective cohort study included patients that had implantation of an S-ICD between February 2014 - May 2020. The 30-day complication rates and long-term risks of inappropriate shocks were compared between patients with and without prior sternotomy.
Results:
Ninety-eight patients (52 ± 15 years old, 43% men, BMI 29 ± 6, 72% primary prevention, 28% ischemic cardiomyopathy, median LVEF 30% (IQR 25-45%)) underwent S-ICD implantation, among whom 19 (19.4%) had a prior sternotomy. The median time between sternotomy and S-ICD implantation was 96 (IQR 4.1-306) months. The sternal coil was primarily implanted left of the sternum (n=17/19, 89%). A two-incision technique was used in 79% of patients with prior sternotomy vs. 65% without sternotomy (p=0.23). The 30-day complication rate was similar between those with and without prior sternotomy (n=1/19 vs. n=10/79, 5% vs. 13%, p=0.36). The only 30-day complication in patients with prior sternotomy was a hematoma without intervention. The 30-day complications in patients without prior sternotomy included: superficial site infection resolving with brief antibiotics (n=4), inappropriate shock (n=3), lead migration requiring revision (n=2), and a hematoma without intervention (n=1). Over a median follow-up of 17.1 (IQR 3.4-29.1) months, the frequency of inappropriate shocks was similar between patients with and without prior sternotomy (n=1/19 and n=6/79, 5% vs. 8%, p=0.72). The median time to inappropriate shock from S-ICD implantation was 1.1 (IQR 0.1-19.8) months. The mechanisms of inappropriate shocks were T-wave oversensing or other oversensing (n=5/7, 72%), air in the pocket (n=1/7, 14%), and atrial tachycardia (n=1/7, 14%).
Conclusions:
Implantation of S-ICD in patients with prior sternotomy was not associated with an increased risk of 30-day complications or inappropriate shocks. These outcomes need to be confirmed in larger, multicenter studies.
Excimer laser lead extraction by femoral approach
