Evaluation of a morphological filter in mean cardiac output determination: application to left ventricular assist devices

A morphological filter (MF) is presented for the determination of beat-to-beat mean rotary left ventricular assist device (LVAD) flow rate, measured using an implanted flow probe. The performance of this non-linear filter was assessed using LVAD flow rate (Q(LVAD)) data sets obtained from in silico and in vivo sources. The MF was compared with a third-order Butterworth filter (BWF) and a 10-s moving average filter (MAF). Performance was assessed by calculating the response time and steady state error across a range of heart rates and levels of noise. The response time of the MF was 3.5 times faster than the MAF, 0.5 s slower than the BWF, and had a steady state error of 2.61 %. It completely removed pulsatile signal components caused by residual ventricular function, and tracked sharp transient changes in Q(LVAD) better than the BWF. The use of a two-stage MF improved the noise immunity compared to the single-stage MF. This study showed that the good performance characteristics of the non-linear MF make it a more suitable candidate for embedded real-time processing of Q(LVAD) than linear filters

Clinical and cost effectiveness of left ventricular assist devices as a bridge to heart transplantation for people with end stage heart failure: a systematic review and economic evaluation

Aims To evaluate the clinical and cost-effectiveness of left ventricular (LV) assist devices (LVADs) as a bridge to transplant (BTT) for people with end-stage heart failure (ESHF) through a systematic review and economic evaluation.Methods and results The systematic review and economic evaluation was conducted according to internationally recognized methods. The search strategy identified systematic reviews, randomized controlled trials, quasi-experimental studies, and observational studies evaluating the effects of LVADs on survival, functional capacity, and quality of life. Cost-effectiveness was assessed through a 5-year decision analytic model to estimate the incremental cost-effectiveness ratio of LVADs compared with usual care. Despite the poor methodological quality of the 18 studies included, LVADs appear beneficial improving survival, functional status, and quality of life. Adverse events are a serious concern. The economic evaluation showed that LVADs had a cost per quality adjusted life year of £65 242 (95% confidence interval £34 194--364 564). Sensitivity analysis showed that post-heart transplant survival gains, pre-heart transplant patient utility, and one-off costs associated with implantation determine cost-effectiveness.Conclusion Although LVADs appear clinically effective as a BTT for people with ESHF, it is unlikely that they will be cost-effective unless costs decrease or the benefits of their use increase.<br/

Effect of robot-assisted radical cystectomy with intracorporeal urinary diversion vs open radical cystectomy on 90-day morbidity and mortality among patients with bladder cancer

Importance: Robot-assisted radical cystectomy is being performed with increasing frequency, but it is unclear whether total intracorporeal surgery improves recovery compared with open radical cystectomy for bladder cancer. Objectives: To compare recovery and morbidity after robot-assisted radical cystectomy with intracorporeal reconstruction vs open radical cystectomy. Design, Setting, and Participants: Randomized clinical trial of patients with nonmetastatic bladder cancer recruited at 9 sites in the UK, from March 2017-March 2020. Follow-up was conducted at 90 days, 6 months, and 12 months, with final follow-up on September 23, 2021. Interventions: Participants were randomized to receive robot-assisted radical cystectomy with intracorporeal reconstruction (n = 169) or open radical cystectomy (n = 169). Main Outcomes and Measures: The primary outcome was the number of days alive and out of the hospital within 90 days of surgery. There were 20 secondary outcomes, including complications, quality of life, disability, stamina, activity levels, and survival. Analyses were adjusted for the type of diversion and center. Results: Among 338 randomized participants, 317 underwent radical cystectomy (mean age, 69 years; 67 women [21%]; 107 [34%] received neoadjuvant chemotherapy; 282 [89%] underwent ileal conduit reconstruction); the primary outcome was analyzed in 305 (96%). The median number of days alive and out of the hospital within 90 days of surgery was 82 (IQR, 76-84) for patients undergoing robotic surgery vs 80 (IQR, 72-83) for open surgery (adjusted difference, 2.2 days [95% CI, 0.50-3.85]; P = .01). Thromboembolic complications (1.9% vs 8.3%; difference, –6.5% [95% CI, –11.4% to –1.4%]) and wound complications (5.6% vs 16.0%; difference, –11.7% [95% CI, –18.6% to –4.6%]) were less common with robotic surgery than open surgery. Participants undergoing open surgery reported worse quality of life vs robotic surgery at 5 weeks (difference in mean European Quality of Life 5-Dimension, 5-Level instrument scores, –0.07 [95% CI, –0.11 to –0.03]; P = .003) and greater disability at 5 weeks (difference in World Health Organization Disability Assessment Schedule 2.0 scores, 0.48 [95% CI, 0.15-0.73]; P = .003) and at 12 weeks (difference in WHODAS 2.0 scores, 0.38 [95% CI, 0.09-0.68]; P = .01); the differences were not significant after 12 weeks. There were no statistically significant differences in cancer recurrence (29/161 [18%] vs 25/156 [16%] after robotic and open surgery, respectively) and overall mortality (23/161 [14.3%] vs 23/156 [14.7%]), respectively) at median follow-up of 18.4 months (IQR, 12.8-21.1). Conclusions and Relevance: Among patients with nonmetastatic bladder cancer undergoing radical cystectomy, treatment with robot-assisted radical cystectomy with intracorporeal urinary diversion vs open radical cystectomy resulted in a statistically significant increase in days alive and out of the hospital over 90 days. However, the clinical importance of these findings remains uncertain. Trial Registration: ISRCTN Identifier: ISRCTN13680280; ClinicalTrials.gov Identifier: NCT03049410

Outcomes in Newly Diagnosed Atrial Fibrillation and History of Acute Coronary Syndromes: Insights from GARFIELD-AF

BACKGROUND: Many patients with atrial fibrillation have concomitant coronary artery disease with or without acute coronary syndromes and are in need of additional antithrombotic therapy. There are few data on the long-term clinical outcome of atrial fibrillation patients with a history of acute coronary syndrome. This is a 2-year study of atrial fibrillation patients with or without a history of acute coronary syndromes