Dual-chamber pacemakers for treating symptomatic bradycardia due to sick sinus syndrome without atrioventricular block: a systematic review and economic evaluation

The BLISTER Score: A Novel, Externally Validated Tool for Predicting Cardiac Implantable Electronic Device Infections, and Its Cost-Utility Implications for Antimicrobial Envelope Use

BACKGROUND

Antimicrobial envelopes reduce the incidence of cardiac implantable electronic device infections, but their cost restricts routine use in the United Kingdom. Risk scoring could help to identify which patients would most benefit from this technology.

METHODS

A novel risk score (BLISTER [Blood results, Long procedure time, Immunosuppressed, Sixty years old (or younger), Type of procedure, Early re-intervention, Repeat procedure]) was derived from multivariate analysis of factors associated with cardiac implantable electronic device infection. Diagnostic utility was assessed against the existing PADIT score (Prior procedure, Age, Depressed renal function, Immunocompromised, Type of procedure) in both standard and high-risk external validation cohorts, and cost-utility models examined different BLISTER and PADIT score thresholds for TYRX (Medtronic; Minneapolis, MN) antimicrobial envelope allocation.

RESULTS

In a derivation cohort (n=7383), cardiac implantable electronic device infection occurred in 59 individuals within 12 months of a procedure (event rate, 0.8%). In addition to the PADIT score constituents, lead extraction (hazard ratio, 3.3 [95% CI, 1.9-6.1]; P<0.0001), C-reactive protein >50 mg/L (hazard ratio, 3.0 [95% CI, 1.4-6.4]; P=0.005), reintervention within 2 years (hazard ratio, 10.1 [95% CI, 5.6-17.9]; P<0.0001), and top-quartile procedure duration (hazard ratio, 2.6 [95% CI, 1.6-4.1]; P=0.001) were independent predictors of infection. The BLISTER score demonstrated superior discriminative performance versus PADIT in the standard risk (n=2854, event rate: 0.8%, area under the curve, 0.82 versus 0.71; P=0.001) and high-risk validation cohorts (n=1961, event rate: 2.0%, area under the curve, 0.77 versus 0.69; P=0.001), and in all patients (n=12 198, event rate: 1%, area under the curve, 0.8 versus 0.75, P=0.002). In decision-analytic modeling, the optimum scenario assigned antimicrobial envelopes to patients with BLISTER scores ≥6 (10.8%), delivering a significant reduction in infections (relative risk reduction, 30%; P=0.036) within the National Institute for Health and Care Excellence cost-utility thresholds (incremental cost-effectiveness ratio, £18 446).

CONCLUSIONS

The BLISTER score (https://qxmd.com/calculate/calculator_876/the-blister-score-for-cied-infection) was a valid predictor of cardiac implantable electronic device infection, and could facilitate cost-effective antimicrobial envelope allocation to high-risk patients.

Cost-effectiveness analysis of leadless cardiac resynchronization therapy

BACKGROUND

The Wireless Stimulation Endocardially for CRT (WiSE-CRT) system is a novel technology used to treat patients with dyssynchronous heart failure (HF) by providing leadless cardiac resynchronization therapy (CRT). Observational studies have demonstrated its safety and efficacy profile, however, the treatment cost-effectiveness has not previously been examined.

METHODS

A cost-effectiveness evaluation of the WiSE-CRT System was performed using a cohort-based economic model adopting a "proportion in state" structure. In addition to the primary analysis, scenario analyses and sensitivity analyses were performed to test for uncertainty in input parameters. Outcomes were quantified in terms of quality-adjusted life year (QALY) differences.

RESULTS

The primary analysis demonstrated that treatment with the WiSE-CRT system is likely to be cost-effective over a lifetime horizon at a QALY reimbursement threshold of £20 000, with a net monetary benefit (NMB) of £3781 per QALY. Cost-effectiveness declines at time horizons shorter than 10 years. Sensitivity analyses demonstrated that average system battery life had the largest impact on potential cost-effectiveness.

CONCLUSION

Within the model limitations, these findings support the use of WiSE-CRT in indicated patients from an economic standpoint. However, improving battery technology should be prioritized to maximize cost-effectiveness in times when health services are under significant financial pressures.

Effects of Dexmedetomidine on Basic Cardiac Electrophysiology in Adults; a Descriptive Review and a Prospective Case Study

Dexmedetomidine (DEX) is a commonly used sedative agent with no or minimal effects on breathing. DEX may also be beneficial in myocardial protection. Since the mechanisms of cardiac effects are not well known, we carried out a descriptive review and examined the effects of DEX on myocardial electrical conduction in a prospective and controlled manner. For the review, clinical studies exploring DEX in myocardial protection published between 2020-2022 were explored. A case study included 11 consecutive patients at a median (range) age of 48 (38-59), scheduled for elective radiofrequency ablation of paroxysmal atrial fibrillation. A bolus dose of DEX 1 µg/kg given in 15 min was followed by a continuous infusion of 0.2-0.7 µg/kg/h. Direct intracardiac electrophysiologic measurements, hemodynamics and oxygenation were measured before and after the DEX bolus. Experimental studies show that DEX protects the heart both via stabilizing cardiac electrophysiology and reducing apoptosis and autophagy after cell injury. The clinical evidence shows that DEX provides cardiac protection during different surgeries. In a clinical study, DEX increased the corrected sinus node recovery time, prolongated the atrioventricular (AV) nodal refractory period and cycle length producing AV nodal Wenckebach retrograde conduction block. DEX has a putative role in organ protection against hypoxic, oxidative and reperfusion injury. DEX slows down the firing of the sinus node and prolongs AV refractoriness.

Audit of data redaction practices in NICE technology appraisals from 1999 to 2019

OBJECTIVES

To assess the extent and type of data redaction in all active technology appraisals (TA) and highly specialised technology (HST) evaluations issued by the National Institute for Health and Care Excellence (NICE) from its conception of the institute to September 2019. To propose policy recommendations for transparency.

METHODS

Structured audit to establish extent of data redaction-proportion of appraisals and specific data categories and assess redaction by: indication, appraisal process, manufacturer, type of data-price, adverse events (AEs), clinical (excluding AEs), incremental quality-adjusted life-years. Longitudinal analysis over 20 years.

RESULTS

All TAs with available documentation and active recommendations (n=408) and HSTs (n=10) published from March 2000 to 11 September 2019 have been assessed for data redaction. Overall, 333 TAs (81.6%) have data redaction, 86 (25.8%) of them are heavily redacted. Clinical data (excluding AEs) are redacted in 268 (65.7%) appraisals, AE data in 128 (31.4%), price in 238 (58.3%). In total, 87% of oncology appraisals have redacted data vs 78% of non-oncology appraisals. 91% of single TAs have redacted data vs 59% of multiple TAs. 25% of final guidance documents (e.g. Final Appraisal Determination - FAD) do not report one or more instance of clinical data. Data redaction increased substantially over time, and is currently at its highest level with 100% of TAs having at least some data redaction in 2019/2020, 96% of appraisals in 2018/2019% and 94% of appraisals in 2017/2018. All 10 HST evaluations have redacted data, with 4 of them being heavily redacted.

CONCLUSIONS

Documents supporting NICE TA and HST recommendations are significantly redacted, thereby concealing clinical and economic data of importance to patients, clinicians and researchers. Documents remain redacted on the NICE website for years. Policy change is required to ensure transparency of data underpinning NICE's decisions.

Clinical review of sick sinus syndrome and atrial fibrillation

Sick sinus syndrome (SSS) is a set of diseases with abnormal cardiac pacing, which manifests as diverse cardiac arrhythmias, especially bradycardia. The clinical presentation is inconspicuous in the early stage, but with the progression of this disease, patients may present with symptoms and signs of end-organ hypoperfusion. As a common result in the natural history of the disease, SSS coexisting with atrial fibrillation (AF) forms the basis of bradycardia-tachycardia syndrome. Age-related interstitial fibrosis is considered to be the common pathophysiological mechanism between SSS and AF. The combination of these diseases will adversely affect the condition of patients and the efficiency of subsequent treatment. Although the exact mechanism is not clear to date, the extensive structural and electrical remodeling of the atrium are considered to be the important mechanism for the occurrence of AF in patients with SSS. Pacemaker implantation is the first-line treatment for symptomatic patients with SSS and documented bradycardia history. In view of the adverse effects of AF on the treatment of SSS, researchers have focused on evaluating different pacing modes and algorithms to reduce the risk of AF during pacing. Catheter ablation may also be used as an alternative second-line therapy for some patients with SSS and AF.

Preclinical immunotherapy with Cytokine-Induced Killer lymphocytes against epithelial ovarian cancer

Despite improvements in surgery and medical treatments, epithelial ovarian cancer (EOC) remains the most lethal gynaecological malignancy. Aim of this study is to investigate the preclinical immunotherapy activity of cytokine-induced killer lymphocytes (CIK) against epithelial ovarian cancers, focusing on platinum-resistant settings. We generated CIK ex vivo starting from human peripheral blood samples (PBMCs) collected from EOC patients. Their antitumor activity was tested in vitro and in vivo against platinum-resistant patient-derived ovarian cancer cells (pdOVCs) and a Patient Derived Xenograft (PDX), respectively. CIK were efficiently generated (48 fold median ex vivo expansion) from EOC patients; pdOVCs lines (n = 9) were successfully generated from metastatic ascites; the expression of CIK target molecules by pdOVC confirmed pre and post treatment in vitro with carboplatin. The results indicate that patient-derived CIK effectively killed autologous pdOVCs in vitro. Such intense activity was maintained against a subset of pdOVC that survived in vitro treatment with carboplatin. Moreover, CIK antitumor activity and tumor homing was confirmed in vivo within an EOC PDX model. Our preliminary data suggest that CIK are active in platinum resistant ovarian cancer models and should be therefore further investigated as a new therapeutic option in this extremely challenging setting.

Arrhythmia Perception and Quality of Life in Bradyarrhythmia Patients Following Permanent Pacemaker Implantation

Although studies have evaluated the quality of life (QoL) of patients undergoing permanent pacemaker (PPM) placement, their results are inconsistent. To assess arrhythmia perceptions and QoL in bradyarrhythmia patients following PPM implantation, 137 patients completed demographic, arrhythmia perception, and QoL questionnaires before and six months after implantation. Before implantation, they reported fatigue (74.1%), dizziness (72.9%), dyspnea (64.7%), chest pain (62.4%), and heart fluttering (54.1%). After implantation, arrhythmia perceptions and QoL showed significant improvement (p < .05), except vitality (p > .05). However, patients with arrhythmia for more than three years, three or more PPM implants, two or more comorbidities, or were 41-50 years showed no significant QoL improvement. Doctors and hospital educators, rather than nurses, provided the most PPM information to patients. Since nurses provide primary in-hospital care to PPM patients, they should impart more patient education while considering individual characteristics in caring situations to enhance patients' QoL.

Optimising pacemaker therapy and medical therapy in pacemaker patients for heart failure: protocol for the OPT-PACE randomised controlled trial

INTRODUCTION

Permanent artificial pacemaker implantation is a safe and effective treatment for bradycardia and is associated with extended longevity and improved quality of life. However, the most common long-term complication of standard pacemaker therapy is pacemaker-associated heart failure. Pacemaker follow-up is potentially an opportunity to screen for heart failure to assess and optimise patient devices and medical therapy.

METHODS AND ANALYSIS

The study is a multicentre, phase-3 randomised trial. The 1200 participants will be people who have a permanent pacemaker for bradycardia for at least 12 months, randomly assigned to undergo a transthoracic echocardiogram with their pacemaker check, thereby tailoring their management directed by left ventricular function or the pacemaker check alone, continuing with routine follow-up. The primary outcome measure is time to all-cause mortality or heart failure hospitalisation. Secondary outcomes include external validation of our risk stratification model to predict onset of heart failure and quality of life assessment.

ETHICS AND DISSEMINATION

The trial design and protocol have received national ethical approval (12/YH/0487). The results of this randomised trial will be published in international peer-reviewed journals, communicated to healthcare professionals and patient involvement groups and highlighted using social media campaigns.

TRIAL REGISTRATION NUMBER

NCT01819662.

Effects of permanent cardiac pacemaker implantation on vascular endothelial function, blood coagulation and cardiac function in patients with bradycardia

Changes in vascular endothelial function, blood coagulation and cardiac function indexes after the implantation of a permanent cardiac pacemaker in patients with bradycardia were investigated. A total of 53 healthy people and 117 patients with bradycardia in Jining First People's Hospital from January 2015 to August 2017 were selected. Factor VIII: coagulation (FVIII:C), von Willebr and factor (vWF), antithrombin activity (AT:A), D-dimmer (D-D), thrombomodulin (TM), tissue factor (TF), left ventricular ejection fraction (LVEF) and left ventricular end-systolic volume (LVESV) in the non-pacemaker group and the pacemaker group were significantly different from those in the control group (P<0.05), in which FVIII:C, vWF, D-D, TM, TF and LVESV were significantly higher than those in the control group, while LVEFs were significantly lower than that in the control group. After the implantation of a pacemaker, the FVIII:C, vWF, fibrinogen (FIB), D-D, TF and LVESV in patients were significantly higher than those before implantation (P<0.05), while the LVEF was significantly lower than that before implantation (P<0.05). In addition, in different pacemaker groups, there were no significant differences in blood coagulation and vascular endothelial indexes, but differences in cardiac function levels were obvious, in which LVEF in dual-chamber (DDD) pacemaker group was significantly higher than that in ventricular inhibited (VVI) pacemaker group, and LVESV in the former was significantly lower than that in the latter (P<0.05). Finally, here was no significant difference in the quality of life of patients implanted with different pacemakers (P>0.05), but the quality of life of patients in the DDD pacemaker group was better than that of patients in the VVI group. Therefore, implanting pacemakers in patients with bradycardia affects vascular endothelial function, blood coagulation, and cardiac function indexes in patients, and complications become less after the implantation of DDD pacemakers.

Cost-utility of surgical sutureless bioprostheses vs TAVI in aortic valve replacement for patients at intermediate and high surgical risk

BACKGROUND

Meta-analyses of studies comparing transcatheter aortic valve implants (TAVIs) and sutureless aortic valve replacement (SU-AVR) show differing effectiveness and safety profiles. The approaches also differ in their surgical cost (including operating room and device).

OBJECTIVE

The objective of this study was to assess the incremental cost-utility of SU-AVR vs TAVIs for the treatment of intermediate- to high-risk patients in the US, Germany, France, Italy, UK, and Australia.

METHODS

A patient-level simulation compares in-hospital pathways of patients undergoing SU-AVR or TAVIs; later, patient history is modeled at the cohort level. Hospital outcomes for TAVIs reproduce data from recent series; in SU-AVR patients, outcomes are obtained by applying relative efficacy estimates in a recent meta-analysis on 1,462 patients. After discharge, survival depends on the development of paravalvular leak and the need for dialysis. A comprehensive third-party payer perspective encompassing both in-hospital and long-term costs was adopted.

RESULTS

Due to lower in-hospital (4.1% vs 7.0%) and overall mortality, patients treated with SU-AVR are expected to live an average of 1.25 years more compared with those undergoing TAVIs, with a mean gain of 1.14 quality-adjusted life-years. Both in-hospital and long-term costs were lower for SU-AVR than for TAVIs with total savings ranging from $4,158 (France) to $20,930 (US).

CONCLUSION

SU-AVR results dominant when compared to TAVIs in intermediate- to high-risk patients. Both in-hospital and long-term costs are lower for SU-AVR than for TAVI patients, with concomitant significant gains in life expectancy, both raw and adjusted for the quality of life.