Cooperative Adaptive Cruise Control Based on Reinforcement Learning for Heavy-Duty BEVs

Advanced driver assistance systems (ADAS) are playing an increasingly important role in supporting the driver to create safer and more efficient driving conditions. Among all ADAS, adaptive cruise control (ACC) is a system that provides consistent aid, especially in highway mobility, guaranteeing safety by minimizing the possible risk of collision due to variations in the speed of the vehicle in front, automatically adjusting the vehicle velocity and maintaining the correct spacing. Theoretically, this type of system also makes it possible to optimize road throughput, increasing its capacity and reducing traffic congestion. However, it was found in practice that the current generation of ACC systems does not guarantee the so-called string stability of a vehicle platoon and can therefore lead to an actual decrease in traffic capacity. To overcome these issues, new cooperative adaptive cruise control (CACC) systems are being proposed that exploit vehicle-to-vehicle (V2V) connectivity, which can provide additional safety and robustness guarantees and introduce the possibility of concretely improving traffic flow stability

Effective nonapical left ventricular pacing with quadripolar leads for cardiac resynchronization therapy

Background: Current guidelines recommend avoiding apical left ventricular (LV) pacing for cardiac resynchronization therapy (CRT). Aims: We investigated the feasibility of nonapical pacing with the current quadripolar LV lead technology. Methods: We analyzed consecutive patients who received CRT with an LV quadripolar lead. The post­­implantation position of each electrode of the LV lead was designated as basal, mid, or apical. The pacing capture threshold (PCT) and phrenic nerve stimulation (PNS) threshold were assessed for each electrode. Results: We enrolled 168 patients. A total of 8 CRT defibrillators were from Biotronik (with Sentus OTW QP leads), 98 were from Boston Scientific (with 21 Acuity X4 Spiral and 77 Acuity X4 Straight leads), and 62 from St. Jude Medical (with Quartet leads). The median (interquartile range) number of electrodes at nonapical segments per patient was 3 (1–4) with Biotronik Sentus leads, 4 (3–4) with spiral ­design Boston Scientific leads, 4 (3–4) with straight Boston Scientific leads, and 3 (3–4) with St. Jude Medical Quartet leads (P = 0.045). Three patients (38%) with Biotronik Sentus leads, 21 (100%) with spiral ­design Boston Scientific leads, 69 (90%) with straight ­design Boston Scientific leads, and 49 (79%) with St. Jude Medical Quartet leads (P < 0.001) had at least 1 electrode located at nonapical segments linked with a PNS ­PCT safety margin of more than 2 V. During the 6­month follow ­up, PNS was detected in 4 patients and was eliminated with reprogramming. No significant changes in PCT were detected during follow ­up. Conclusions: Quadripolar leads allowed nonapical pacing with acceptable electrical parameters in the majority of CRT recipients, although differences were found among the currently available devices

Persistent atrial fibrillation worsens heart rate variability, activity and heart rate, as shown by a continuous monitoring by implantable biventricular pacemakers in heart failure patients

Persistent AFWorsens Conditions of HF Patients. Background: Atrial fibrillation (AF) induces loss of atrial contribution, heart rate irregularity, and fast ventricular rate. Objectives: The objectives of the study were to accurately measure AF incidence and to investigate the mutual temporal patterns of AF and heart failure (HF) in patients indicated to cardiac resynchronization therapy. Methods: Four hundred ten consecutive patients (70% male, age 69   11) with advanced HF (NYHA = 3.0   0.6), low ejection fraction (EF = 27   9%), and ventricular conduction delay (QRS=165 29 ms) received a biventricular pacemaker. Enrolled patients were divided into two groups: G1 = 249 patients with no AF history, G2 = 161 patients with history of paroxysmal/persistent AF. Results: In a median follow-up of 13 months, AF episodes longer than 5 minutes occurred in 105 of 249 (42.2%) G1 patients and 76 of 161 (47.2%) G2 patients, while AF episodes longer than one day occurred in 14 of 249 (5.6%) G1 patients and in 36 of 161 (22.4%) G2 patients. Device diagnostics monitored daily values of patient activity, night heart rate (NHR), and heart rate variability (HRV). Comparing 30-day periods beforeAF onset and during persistent AF, significant (P<0.0001) changes were observed in patient activity, which decreased from 221   13 to 162   12 minutes, and in NHR, which increased from 68   3 to 94   7 bpm. HRV significantly decreased (from 75   5 ms before AF onset to 60   6 ms after AF termination). NHR during AF was significantly (P < 0.01) and inversely correlated (R2 = 0.73) with activity, with a significant lower activity associated with NHR ≥ 88 bpm. Conclusion:AFis frequent inHFpatients. PersistentAFis associated with statistically significant decrease in patient activity and HRV and NHR increase.

Closed loop stimulation in prevention of vasovagal syncope. Inotropy controlled pacing in vasovagal syncope (INVASY): A multicentre randomized, single blind, controlled study

Objectives: To determine whether dual-chamber rate-adaptive Closed Loop Stimulation (CLS) could prevent recurrence of Vasovagal Syncope (VVS). Background: During VVS, an increase in myocardial contractility associated with a reduction of ventricular filling produces an increase in baroreceptor afferent flow and a consequent decrease in the heart rate. The CLS algorithm is a form of rate-adaptive pacing, which responds to myocardial contraction dynamics, by measuring variations in right ventricular intracardiac impedance: during an incipient VVS it could increase paced heart rate and avoid bradycardia, arterial hypotension and syncope. Methods: Fifty patients (27 males, mean age 59 ± 18 year) with severe and recurrent vasovagal syncope and positive Head Up Tilt Test (HUTT) with cardioinhibition, received a CLS pacemaker (INOS2, Biotronik GmbH Co., Germany). The primary end point was recurrence of two VVSs during a minimum of 1 year of follow-up. Randomization between DDD-CLS and DDI mode (40 bpm) pacing was performed only during the first stage of the study (first year): 9/26 randomized to DDI mode (control group) and 17/26 in DDD-CLS mode. All the 24 patients recruited in the second stage of the study (second year) were programmed in DDD-CLS mode. Results: Of the nine patients randomized to the DDI mode, seven had recurrences of syncope during the first year. At the end of the first year the nine patients were reprogrammed to the CLS mode and no syncope occurred after reprogramming. The 41 patients programmed to CLS had a mean follow-up of 19 ± 4 months: none reported VVS, only four (10%) reported occasional presyncope and their quality of life greatly improved. Positive HUTT at the end of the first year failed to predict the clinical response to CLS pacing. Conclusions: The study demonstrates the effectiveness of CLS pacing in preventing cardioinhibitory VVS. A possible placebo effect of pacemaker implantation occurred in 22% of patients. © 2004 The European Society of Cardiology. Published by Elsevier Ltd. All rights reserved

Impact of mitral regurgitation on the outcome of patients treated with CRT-D: data from the InSync ICD Italian Registry.

Background: We assessed the influence of clinically significant mitral regurgitation (MR) on clinical-echocardiographic response and outcome in heart failure (HF) patients treated with a biventricular defibrillator (cardiac resynchronization therapy defibrillator [CRT-D]). Methods and Results: A total of 659 HF patients underwent successful implantation of CRT-D and were enrolled in a multicenter prospective registry (median follow-up of 15 months). Following baseline echocardiographic evaluation, patients were stratified into two groups according to the severity of MR: 232 patients with more than mild MR (Group MR+: grade 2, 3, and 4 MR) versus 427 patients with mild (grade 1) or no functional MR (Group MR−). On 6- and 12-month echocardiographic evaluation, MR was seen to have improved in the vast majority of MR+ patients, while it remained unchanged in most MR− patients. On 12-month follow-up evaluation, a comparable response to CRT was observed in the two groups, in terms of the extent of left ventricular reverse remodeling and combined clinical and echocardiographic response. During long-term follow-up, event-free survival did not differ between MR+ and MR− patients, even when subpopulations of patients with ischemic heart disease and with dilated cardiomyopathy were analyzed separately. On multivariate analysis, the only independent predictor of death from any cause was the lack of β-blocker use. Conclusions: This observational analysis supports the use of CRT-D in HF patients with clinically significant MR; MR had no major influence on patient outcom