SynCardia Total Artificial Heart patients experienced acceptable outcomes after one year

159

A study published in the ASAIO Journal examined the outcomes of 47 patients who had received SynCardia Total Artificial Heart support for greater than one year. Among them, 72% received donor heart transplants and one (2%) was awaiting a donor heart.

Seventy-four per cent of patients who were supported by the SynCardia temporary Total Artificial Heart for more than a year were either bridged to a donor heart or awaiting one, according to a study published in the ASAIO Journal for the American Society for Artificial Internal Organs.

In the introduction of the paper, “Results with SynCardia Total Artificial Heart beyond one year,” the authors write, “After a minimum of one year of support, 34 patients (72%) were successfully transplanted, 12 patients (24%) died while on device support, and 1 patient (2%) is still supported.”

The study by 18 cardiac surgeons from around the world was published in December 2014, eight days before the FDA approved an application by SynCardia Systems to study the effective use of the SynCardia Total Artificial Heart for permanent use, also called destination therapy.

In the USA, the SynCardia Total Artificial Heart is currently approved as a bridge to a donor heart transplant for patients dying of end-stage biventricular heart failure. The authors studied medical records of 47 patients who received the SynCardia Total Artificial Heart between 1989 and 2011 and were supported for at least one year on the device. The mean age of patients was 50±1.57 years and the median support time was 554 days (365–1,373 days).

Thirty-three patients (70.2%) were categorised to an INTERMACS class. Twenty-three were in INTERMACS class I, seven were in class II and three were on class III.

Forty patients (85%) were discharged home. Of the seven patients who remained in-hospital, five were from the USA where, at the time of their Total Artificial Heart support, a portable driver was not available yet.

Of those who died, only two were from device failure. “In long-term support, the use of [the Total Artificial Heart] was safe,” according to the study. “Device malfunctions are generally referred to as a rare complication with the [Total Artificial Heart].” Infections and haemorrhagic events were the leading causes of death among the patients in the study.

There were several other results among the study’s findings: 

  • Every one of the 34 patients who had a donor heart transplant following long-term use of the SynCardia Heart successfully survived the surgery.
  • Following SynCardia Total Artificial Heart implant surgery, 30 patients needed renal replacement therapy; 22 (73%) recovered kidney function.
  • Three of the 34 patients who had a donor heart transplant died, all from graft (donor heart) rejection. The median time of survival post-transplant was 145 days (50-328 days).
  • There were 0.083 TE (thromboembolic) events per patient month. “This data show that long-term (Total Artificial Heart) support does not increase the risk of TE events,” according to the report.
  • Patients with a body surface area of less than 1.8m had an increased incidence of death, haemorrhagic events and systemic infections. Standard fit criteria for use of the SynCardia Total Artificial Heart include a minimum body surface area of 1.7m and an anteroposterior distance greater than 10cm from the sternum to the 10th thoracic vertebra.

The paper concludes by stating that “the SynCardia (Total Artificial Heart) has emerged as a robust form of mechanical circulatory support for patients with biventricular failure. This study illustrates that support using the SynCardia (Total Artificial Heart) beyond one year has acceptable outcomes, but further improvements in the device, patient selection and long-term patient management need to be achieved to further reduce the major complications of infection, thromboembolic and haemorrhagic events.”