by
Lauren Dubinsky, Senior Reporter | May 24, 2016
From the May 2016 issue of HealthCare Business News magazine
S-ICDs
Patients with sudden cardiac arrest are traditionally treated with transvenous ICDs, but another option was introduced to the market when Boston Scientific received FDA approval for its subcutaneous ICD (S-ICD) system in 2012, which are essentially leadless ICDs. Boston Scientific scored approval for its second-generation S-ICD system, the EMBLEM S-ICD System, in March 2015.
The new generation is 20 percent thinner and is expected to last 40 percent longer than the previous system, but it is not MR compatible. S-ICDs utilize a pulse generator and electrode beneath the skin, instead of having a lead run through blood vessels. During the procedures, a shocking coil is implanted in the area under the left arm and tunneled through the soft tissues of the body.
Unlike S-ICDs, the leads are the biggest drawback for ICDs because they are susceptible to breaking and other complications. The patients also don’t have to undergo vascular surgery to have it implanted, which lessens the chances of systemic infections and complications that are associated with endovascular lead implantation or extraction.
However, one of the downsides of S-ICDs is that they don’t have some of the functionality that regular ICDs have. For example, ICDs are able to pace patients out of bad heart rhythms, but the current generation of S-ICDs can’t do that because they don’t have a lead that’s enough in contact with the heart. Medtronic is currently working on a new S-ICD that will still be placed outside of the vasculature and have all of the advantages of the current S-ICD, but will also be able to pace the patient’s heart out of a bad rhythm. It is not, however, intended to be MRcompatible.
CRT-Ds
In February, Medtronic announced that it received FDA approval for the first and only MR-compatible cardiac resynchronization therapy defibrillators (CRT-Ds) for treating heart failure. The Amplia MRI Quad CRT-D SureScan and Compia MRI Quad CRT-D SureScan systems are both approved for MR scans. Among the population of patients who have have defibrillators and CRT-Ds, about 40 percent of them will require an MR exam within the first four years of having the device implanted, according to Dr. David Steinhaus, vice president and general manager of the heart failure business and medical director for the cardiac rhythm and heart failure division of Medtronic.
CRT-Ds were previously not recommended by the FDA to be used during MR exams because of the potential interaction between the MR and device that could put the patients at risk. In addition, CMS doesn’t provide coverage for MR exams conducted on patients with non-MR-compatible implanted cardiac devices. The CRT-Ds have the same functionality as ICDs, but also have the ability to pace both sides of the heart. It’s used in patients when their heart contractions are out of sync. “A defibrillator is sort of an insurance policy — they are there in case you need it if your rhythm goes out of whack,” says Steinhaus. “The CRT defibrillator has that capability, but it is also used to pace the heart with every beat so that the heart will function better.”
