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Symptoms and quality of life were assessed among human immunodeficiency virus (HIV)-infected individuals initiating their first course of antiretroviral therapy. Symptoms, which were mostly mild or moderate, were common in the first year and significantly affected the patients' quality of life. Quality of life was inversely related to the number of symptoms and in the change in the number of symptoms from baseline. [ABSTRACT FROM AUTHOR]

Key Points: Question: Is antitachycardia pacing followed by shock clinically equivalent to a shock-only strategy in primary prevention implantable cardioverter-defibrillator recipients when programmed with long detection to therapy delays? Findings: In this randomized clinical trial that included 2626 patients and was designed as an equivalence trial with sequential superiority analysis of each group, anti-tachycardia pacing prior to shock reduced the relative risk of time to first all-cause shock by 28%, a significant difference. Meaning: Antitachycardia pacing is effective as a first-line therapy in prolonging time to first all-cause shock, although the shock burden was not significantly different between the groups during follow-up. Importance: The emergence of novel programming guidelines that reduce premature and inappropriate therapies along with the availability of new implantable cardioverter-defibrillator (ICD) technologies lacking traditional endocardial antitachycardia pacing (ATP) capabilities requires the reevaluation of ATP as a first strategy in terminating fast ventricular tachycardias (VTs) in primary prevention ICD recipients. Objective: To assess the role of ATP in terminating fast VTs in primary prevention ICD recipients with contemporary programming. Design, Setting, and Participants: This global, prospective, double-blind, randomized clinical trial had an equivalence design with a relative margin of 35%. Superiority tests were performed at interim analyses and the final analysis if equivalence was not proven. Patients were enrolled between September 2016 and April 2021 at 134 sites in 8 countries, with the last date of follow-up on July 6, 2023. Patients were required to have an indication for a primary prevention ICD, including left ventricular ejection fraction less than or equal to 35%. Interventions: Patients were randomized in a 1:1 ratio to receive ATP plus shock vs shock only. Main Outcomes and Measures: The primary end point was time to first all-cause shock. Secondary end points included time to first appropriate shock, time to first inappropriate shock, all-cause mortality, and the composite of time to first all-cause shock plus all-cause mortality. Results: A total of 2595 patients were randomized (mean age, 63.9 years; 22.4% were females). At a mean follow-up of 38 months, first all-cause shock occurred in 129 participants in the ATP plus shock group and 178 participants in the shock only group. The hazard ratio (HR) for the primary end point was 0.72 (95.9% CI, 0.57-0.92), with P =.005 for superiority of the ATP plus shock group over the shock only group. During follow-up in an intention-to-treat analysis, the total shock burden per 100 patient-years was not statistically different, at 12.3 and 14.9, respectively (P =.70). Conclusions and Relevance: The use of a single burst of ATP prior to shock in primary prevention ICD recipients with modern ICD detection programming prolonged the time to first all-cause ICD shock. Trial Registration: ClinicalTrials.gov Identifier: NCT02923726 This randomized clinical trial assesses the role of antitachycardia pacing in terminating fast ventricular tachycardia in primary prevention patients with implantable cardioverter-defibrillators with contemporary programming. [ABSTRACT FROM AUTHOR]

Effect of QLV on CRT Hemodynamic Response Introduction Cardiac resynchronization therapy (CRT) improves hemodynamic function, as well as reduces hospitalizations and mortality among patients with systolic dysfunction, QRS prolongation, and heart failure. The magnitude of the hemodynamic response is associated with improved outcomes, so optimization of this parameter is a goal of therapy. The purpose of this study was to evaluate the effect of left ventricular (LV) electrical delay, as assessed by the QLV interval, on the acute hemodynamic response to CRT. Methods and Results This study included 31 patients undergoing biventricular ICD placement. At implant, invasive LV dP/dt was measured by a micromanometer catheter during biventricular (BV) or LV only pacing. Both atrial sensing (AS) and atrial pacing (AP) modes were evaluated at 5 different AV delays, tested in randomized order. The QLV interval was measured at the LV pacing site. Compared with intrinsic rhythm, CRT increased LV dP/dtmax by 9.5 ± 8.8% with BV pacing and 10.0 ± 9.2% with LV pacing (P = 0.38) during AS. With AP, CRT increased LV dP/dtmax by 16.0 ± 10.8% and 15.3 ± 11.1%, respectively (P = 0.47). QLV was strongly correlated with the hemodynamic response in all pacing configurations. Multivariate analysis showed that with BV pacing QLV was an independent predictor of the hemodynamic response with a 1.7% increase in %LV dP/dt for every 10 milliseconds prolongation of QLV. Conclusions LV electrical delay is a strong predictor of the acute hemodynamic response to CRT. This relationship is independent of pacing mode. [ABSTRACT FROM AUTHOR]

Abstract: Aims: The SMART CRT study will assess the efficacy of an atrioventricular optimization algorithm to improve reverse remodeling among patients undergoing cardiac resynchronization therapy (CRT) in the presence of interventricular electrical delay. Methods and results: The SMART CRT study is a global, multicenter, prospective, randomized study of patients undergoing CRT implantation. The primary endpoint of this trial is response rate to CRT, defined as decrease in left ventricular end‐systolic volume (LVESV) ≥15% at 6 months compared to preimplant baseline. Additional prespecified analyses are: (1) clinical composite endpoint combining all‐cause mortality, heart failure events, New York Heart Association class, and Quality of Life (using a patient global assessment instrument); (2) the individual components of the clinical composite endpoint; (3) 6‐minute walk distance; (4) Kansas City Cardiomyopathy Questionnaire; (5) LVESV as a continuous variable; and (6) absolute left‐ventricular ejection fraction. Subjects with intraventricular delay ≥ 70 ms measured between the right ventricular and left ventricular pacing leads will be randomized in a 1:1 ratio to have either an AV Delay and pacing chamber determined by SmartDelay™ or a Fixed AV Delay of 120 ms with biventricular pacing. Enrollment of an estimated 726 of subjects from up to 100 centers worldwide is planned to achieve 436 randomized subjects and 370 complete data sets required to power the primary endpoint. Conclusions: This trial will provide important data regarding the importance of AV Delay programming in patients with prolonged interventricular delay at the pacing sites. [ABSTRACT FROM AUTHOR]

Background The NECTAR-HF study evaluated safety and feasibility of vagal nerve stimulation (VNS) for the treatment of heart failure patients. The first six-month randomized phase of the study did not show improvement in left ventricular remodelling in response to VNS. This study reports the 18-month results and provides novel findings aiming to understand the lack of efficacy of VNS, including a new technique assessing the effects of VNS. Methods Ninety-six patients were randomized 2:1 to active or inactive VNS for 6 months, thereafter VNS was activated for all patients. The primary safety endpoint was 18-month all-cause mortality. Results Ninety-one patients continued in the long-term evaluation with active VNS. The on-therapy survival estimate at 18 months was 95% with a 95% one-sided lower confidence limit of 91%, (better than the predefined criterion). Left ventricular systolic volume decreased in the crossover group (VNS OFF → ON; 144 ± 37 to 139 ± 40, p < 0.05) after VNS activation; LVESD (5.02 ± 0.77 to 4.96 ± 0.82, p > 0.05) and LVEF (33.2 ± 4.9 to 33.3 ± 6.5, p > 0.05) did not change. A new technique to detect subtle heart rate changes during Holter recordings, i.e. “heat maps”, revealed that VNS evoked heart rate response in only 13/106 studies (12%) at 6 and 12 months with active VNS. Conclusions Although a favourable long-term safety profile was found, improvements in the efficacy endpoints were not seen with VNS. A new technique for detecting acute heart rate responses to VNS suggests that the recruitment of nerve fibres responsible for heart rate changes were substantially lower in NECTAR-HF than in pre-clinical models. [ABSTRACT FROM AUTHOR]

Background: The design of pacemaker leads has continued to evolve; ease of lead handling, improved electrical performance, andmagnetic resonance imaging (MRI) conditional aspects have becomemore important, while safety remains critical. The INGEVITYTM family leads was designed to provideMRI conditional aspects, decreased diameter, and improved performance of pacemaker leads. The INGEVITY study is an investigational device exemption trial evaluating the acute and chronic safety and effectiveness of these leads. Methods: Consecutive patients were included in 77 institutions worldwide, where 1,657 leads (846 right ventricular active fixation leads, 213 right ventricular passive fixation leads, 121 right atrial passive fixation preformed J-leads, and 477 right atrial active fixation leads)were implanted or attempted in 1,060 subjects. Results: At 3-month follow-up, the electrical performance were: mean pacing threshold 0.67 V at 0.5-ms pulse width, pacing impedance 773 ohms, mean P-wave amplitude 4.8 mV, and R-wave amplitude 16.5 ± 6.5 mV. Over a median follow-up of 31 months, 93 subjects died and 33 subjects reported lead-related complications. Lead-related complication-free rate from 0 to 3 months and 3 to 12 months for all leads was 98.4% and 99.7%, respectively. The hazard of lead-related complications was observed to be decelerating over the course of follow-up (Weibull shape = 0.23). The overall lead dislodgment rate observed in the study was 1.3%, the perforation ratewas 0.0%, and the pericardial effusion rate was 0.3%. Conclusions: The clinical performance of the INGEVITY lead demonstrated a high lead-related complication-free rate over 12months of follow-up and excellent electrical characteristics. [ABSTRACT FROM AUTHOR]

Background We hypothesized that survival in implantable cardioverter defibrillator (ICD) and cardiac resynchronization therapy defibrillator (CRT-D) patients is predicted by baseline Heart Rate Score. Methods Heart Rate Score is determined from the atrial paced and sensed histogram of a DDD ICD or CRT-D, and defined as percent of beats in the histogram in the tallest 10 beats/min range bin. It was calculated at initial remote monitoring for patients enrolled in LATITUDE® without persistent atrial fibrillation, and with pulse generators implanted in 2006-2011. Univariate, multivariate, and Kaplan-Meier analyses determined the impact of Heart Rate Score on survival. Results Of 57,893 ICDs and 67,929 CRT-Ds followed for 2.4 ± 1.5 years, each 10% increase in Heart Rate Score was associated with decreased survival (CRT-D hazard ratio [HR] 1.07 95%, confidence interval 1.06-1.07, P < 0.0001; ICD HR 1.05, 95% confidence interval 1.04-1.06, P < 0.0001). Multivariate analysis showed survival decreased with increasing age, atrial fibrillation, presence of a shock in first-year follow-up, and increasing programmed lower pacing rate in ICD and CRT-D patients. Increased percent right ventricular pacing predicted mortality in ICD patients, while male gender and lower percent left ventricular pacing predicted mortality in CRT patients. Heart Rate Score predicted survival independent of those variables. Heart Rate Score correlates with heart rate variability (standard deviation of average R-R intervals [SDANN]) when both are obtainable, but SDANN was only present in 6% of patients with Heart Rate Score >70%. Conclusion A simple device histogram measure, Heart Rate Score, predicts survival in ICD and CRT-D patients independent of the available variables, and even when SDANN is unavailable. [ABSTRACT FROM AUTHOR]