An overview of mechanical circulatory support in single-ventricle patients.

The population of people with a single-ventricle is continually increasing due to improvements across the spectrum of medical care. Unfortunately, a proportion of these patients will develop heart failure. Often, for these patients, mechanical circulatory support (MCS) represents the only available treatment option. While single-ventricle patients currently represent a small proportion of the total number of patients who receive MCS, as the single-ventricle patient population increases, this number will increase as well. Outcomes for these complex single-ventricle patients who require MCS has begun to be evaluated. When considering the entire population, survival to hospital discharge is 30-50%, though this must be considered with the significant heterogeneity of the single-ventricle patient population. Patients with a single-ventricle have unique anatomy, mechanisms of failure, indications for MCS and the type of support utilized. This has made the interpretation and the generalizability of the limited available data difficult. It is likely that some subsets will have a significantly worse prognosis and others a better one. Unfortunately, with these limited data, indications of a favorable or poor outcome have not yet been elucidated. Though currently, a database has been constructed to address this issue. While the outcomes for these complex patients is unclear, at least in some situations, they are poor. However, significant advances may provide improvements going forward, including new devices, computer simulations and 3D printed models. The most important factor, however, will be the increased experience gained by the heart failure team to improve patient selection, timing, device and configuration selection and operative approach.