Remote monitoring of left ventricular assist device parameters after HeartAssist-5 implantation.

Although several left ventricular assist devices (LVADs) have been used widely, remote monitoring of LVAD parameters has been available only recently. We present our remote monitoring experience with an axial-flow LVAD (HeartAssist-5, MicroMed Cardiovascular, Inc., Houston, TX, USA). Five consecutive patients who were implanted a HeartAssist-5 LVAD because of end-stage heart failure due to ischemic (n=4) or idiopathic (n=1) cardiomyopathy, and discharged from hospital between December 2011 and January 2013 were analyzed. The data (pump speed, pump flow, power consumption) obtained from clinical visits and remote monitoring were studied. During a median follow-up of 253 (range: 80-394) days, fine tuning of LVADs was performed at clinical visits. All patients are doing well and are in New York Heart Association Class-I/II. A total of 39 alarms were received from three patients. One patient was hospitalized for suspected thrombosis and was subjected to physical examinations as well as laboratory and echocardiographic evaluations; however, no evidence of thrombus washout or pump thrombus was found. The patient was treated conservatively. Remaining alarms were due to insufficient water intake and were resolved by increased water consumption at night and summer times, and fine tuning of pump speed. No alarms were received from the remaining two patients. We believe that remote monitoring is a useful technology for early detection and treatment of serious problems occurring out of hospital thereby improving patient care. Future developments may ease troubleshooting, provide more data from the patient and the pump, and eventually increase physician and patient satisfaction. Despite all potential clinical benefits, remote monitoring should be taken as a supplement to rather than a substitute for routine clinical visits for patient follow-up.

Fine-tuning management of the Heart Assist 5 left ventricular assist device with two- and three-dimensional echocardiography.

INTRODUCTION: Left ventricular assist device (LVAD) implantation is a viable therapy for patients with severe end-stage heart failure, providing effective haemodynamic support and improved quality of life. The Heart Assist 5 (Micromed Cardiovascular Inc, Houston, TX) continuous-flow LVAD has been on the market in Europe since May 2009. METHODS: We evaluated nine Heart Assist 5 LVAD patients with two- and three-dimensional transthoracic echocardiographic (TTE) and transoesophageal echocardiographic (TEE) parameters between December 2011 and December 2013. The pre-operative TTE LVAD evaluations included left ventricular (LV) function and structure, quantification of right ventricular (RV) function and tricuspid regurgitation (TR), assessment of aortic and mitral regurgitation, and presence of patent foramen ovale and intra-cardiac clots. Peri-operative TEE determined the inflow cannula and septum position, and assessed the de-airing process while weaning from cardiopulmonary bypass. Post-operative serial follow-up TTE showed the surgical results of LVAD implantation, determined the overall structure and function of the LV, RV and TR, and observed the inflow and outflow cannula position. RESULTS: Nine patients who had undergone Heart Assist 5 LVAD implantation and had been followed up for more than 30 days were included in this study. Eight patients had ischaemic cardiomyopathy and one had adriamycin-induced cardiomyopathy. Pre-implantation data: the mean age of the patients was 52 ± 13 (34-64) years, mean body surface area (BSA) was 1.8 ± 0.2 (1.6-2.0) m2, mean cardiac index (CI) was 2.04 ± 0.4 (1.5-2.6) l/min/m2, mean cardiac output (CO) was 3.7 ± 0.7 (2.6-4.2) l/min, mean ejection fraction (EF) was 23 ± 5 (18-28)%, and right ventricular fractional area contraction (RVFAC) was 43 ± 9 (35-55)%. One patient had aortic valve replacement (AVR) during the LVAD implantation, and excess current alarms and increased power were suspected to be caused by a possible thrombus. Close follow up with TTE studies were carried out to clear the LV of thrombus formation, and the inflow cannula position was checked to maintain the septum in the midline, so preventing the suction cascade. Four patients were followed up for more than two years, and two were followed up for more than a year. Three patients died due to multi-organ failure. Follow-up speed-change TTE studies of six patients showed that the mean speed was 9 800 ± 600 (9 500-10 400) rpm, and mean CO was 4.7 ± 0.3 (4.3-5.0) l/min during the three-month post-implant period. CONCLUSION: We believe that TTE can play a major role in managing LVAD patients to achieve optimal settings for each patient. A large series is mandatory for assessment of echocardiographic studies on Heart Assist 5 LVAD.