[Ventricular assist device – Possibilities of long-term mechanical circulatory support]

Cardiac Rehabilitation in Patients With Ventricular Assist Device

PURPOSE

The aim of this study was to investigate changes in exercise capacity (EC) and quality of life (QoL) of patients with ventricular assist devices (VADs) during cardiac rehabilitation (CR).

METHODS

Data from patients with VAD implantation and subsequent CR between 2007 and 2017 were analyzed retrospectively. Measures of the 6-min walk test [6MWT] distance, Functional Independence Measure [FIM], ergometry, MacNew Heart Disease Questionnaire [MNH], and Hospital Anxiety and Depression Scale [HADS] at entry and discharge were examined.

RESULTS

Data from 110 patients (age 53 ± 12 yr; male 82%) were analyzed. Patients improved during CR significantly in the 6MWT (114 ± 85 m, P < .001), ergometry (20 ± 17 W, P = .002), FIM (8 ± 7 points, P < .001), and MNH (0.8 ± 0.7 points, P < .001). Initial HADS levels were high with a mean value of 9 and did not improve during CR (-0.4 ± 5 points, P = .637). Significant differences of improvements in the 6MWT were observed between left and biventricular VAD (129 ± 90 m vs 85 ± 67 m, P = .043) as well as destination therapy and bridge-to-transplant (184 ± 88 m vs 102 ± 82 m, P = .005).

CONCLUSIONS

Patients with VAD implantation had statistically and clinically significant improvements in EC and QoL as assessed with the MNH during CR. Patients on destination therapy showed a larger benefit from CR than bridge-to-transplant patients and patients with left VAD improved more than biventricular VAD patients.

A Not-Motorized Implantable Device for Partial Circulatory Support: A Proof of Concept Experiment

A fully implantable circulatory assistance device without external connection and lifetime energy supply can eliminate a significant source of morbidity and mortality for patients. Here, we present and discuss concept and preliminary results of an original project for a not-motorized, fully implantable circulatory assistance device. The not-motorized implantable circulatory assistance device (NICA) has been tested into a cardiac simulator that was conceived according to the FDA and ISO standards. The instrumentation incorporated to the cardiac simulator includes probes for the aortic pressure (AoP) proximally to the device, a temperature control system, and one electromagnetic flowmeter to acquire the flow rate (AoF) proximally to the device. A control software allows to modulate the drive parameters such as velocity, acceleration, number of revolutions, the stroke volume, and the heart rate. Experiments have been performed with three different circuit resistances: 2100 dyn s/cm5, 1400, and 700. The AoF increased in the assisted cycles: 71% at 2100 dyn s/cm5, 67% at 1400 dyn s/cm5, and 25% at 700 dyn s/cm5. NICA performs a partial but significant support of AoF without energy supply. The improvement of AoF increases with the increasing of vascular resistances. The feedback received by this preliminary bench experiment acted as a preliminary proof of concept of this new device.