A 19-year-old woman was successfully implanted with the SynCardia temporary Total Artificial Heart and bridged to a donor heart transplant after cardiac surgeons used 3D virtual implantation to determine she was fit-eligible for the procedure, according to a case series in November’s The Journal of Heart and Lung Transplantation. The case series evaluated four other patients for virtual implantation with one other meeting virtual fit criteria despite failing standard criteria.
“On the basis of these criteria, most paediatric and small adult patients are excluded from [SynCardia Total Artificial Heart] placement,” says the report, “Virtual implantation evaluation of the total artificial heart and compatibility: Beyond standard fit criteria”, authored by doctors from the Cincinnati Children’s Hospital Medical Center, The Heart Institute, Ohio, USA.
The case series, which includes videos of virtual implantation, was authored by Ryan A Moore, Peace C Madueme, Angela Lorts, David LS Morales and Michael D Taylor.
The 19-year-old patient had a history of kidney cancer and developed anthracycline-induced cardiomyopathy, which was treated with a heart transplant. After several episodes of organ rejection, she developed restrictive cardiomyopathy.
The rejected donor heart had to be removed, so neither a left ventricular assist device nor a biventricular assist device could be used. The only option left for her survival was the SynCardia Total Artificial Heart. However, the patient did not meet the standard fit criteria for the SynCardia Total Artificial Heart implant. Her body surface area was 1.64 m and the T10 to sternum distance was 8.9cm.
Surgeons decided to use virtual implantation to see if the implant might still be successful. This reveals any issues with compression of intrathoracic structures such as systemic and pulmonary veins, the aorta, lungs and diaphragm. “An accurately scaled 3D surface rendering of the [SynCardia Total Artificial Heart] was placed within a 3D reconstruction of the chest to assess for proper fit,” the case series says. Doctors found that for this patient “proximity measures noted minimal concern for compression of pertinent structures.”
The patient was successfully implanted with “no compression-related post-operative complications,” the series says. Once she was clinically stable, the patient was transitioned to the Freedom portable driver, which provides mobility. She was discharged from the hospital to wait for her donor heart at home. After 14 months of support from the SynCardia Heart, she was successfully bridged to a matching donor heart transplant.
The paper outlines four other instances in which virtual implantation allowed surgeons, patients and their families to make informed decisions based on potential implant complications discovered in the virtual pre-operative implant procedure. “With increasing use of [mechanical circulatory support] devices in adolescent and young adult patients, virtual compatibility testing allows for improved eligibility despite failing standard fit criteria,” the series concluded.
The technology also can help establish compatibility criteria for a smaller 50cc SynCardia Heart, for which SynCardia Systems is working with the FDA to conduct a clinical study. Once results of that study are approved by the FDA, the 50cc, together with the 70cc SynCardia Heart currently in use, would make the SynCardia Total Artificial Heart available for almost all adults and most adolescents. The group at Cincinnati Children’s is putting together a case series evaluating the potential of virtual implantation utilizing the 50cc device in patients with a BSA less than 1.7m.