ICD Options in 2025: Subcutaneous, Transvenous, or Biventricular?

Hypertrophic cardiomyopathy (HCM) was the topic of several sessions at #AHA25, and we were pleased to participate in them, given our HCM Center of Excellence at UTSW. One session explored additional considerations following the decision to proceed with implantable cardioverter defibrillator (ICD) therapy.

The first consideration is whether to implant a transvenous or a subcutaneous ICD. As with many choices, there are advantages and disadvantages in both. The advantage of the transvenous device is that it has been used for 25 years with a good track record of use. It is also able to pace people out of ventricular tachycardia, avoiding a painful shock, and is half the size. The downside is that the lead is inside the vasculature, potentially getting infected and even causing endocarditis. In addition, leads tend to wear out with time. Removing transvenous leads does carry risk because the lead is covered by fibrous tissue. The advantage of the subcutaneous device is that the lead is outside the thorax, less subject to wear and tear, and relatively safe to take out if it gets infected.

With the transvenous device, one has the option to insert a single or a dual-chamber model. There is really no advantage to a dual-chamber device except if the patient needs atrial pacing. In addition, the complication rate for dual-chamber leads is higher than for single-chamber leads. The third choice is whether to put a single-coil defibrillation lead or a dual-coil ICD defibrillation lead. The advantage with a single-coil lead is that it is much easier to take out, but the defibrillation thresholds may be a bit higher.

Recent HCM attention has focused on new medical therapies to improve symptoms. However, device therapy remains a cornerstone of the management of HCM, with many more considerations and options than in the past.