Meta-analysis of Usefulness of Phrenic Nerve Stimulation in Central Sleep Apnea.

Transvenous neurostimulation of the phrenic nerve (PNS) is a potentially improved and unique approach to the treatment of central sleep apnea (CSA). There have been multiple studies with limited individuals evaluating the efficacy of PNS. Our aim was to review and pool those studies to better understand whether phrenic nerve stimulation is efficacious in the treatment of CSA. The initial search on Pubmed retrieved a total of 97 articles and after screening all articles, only 5 could be included in our quantitative analysis. Pooling of data from 5 studies with a total of 204 patients demonstrated a reduction of mean apnea hypopnea index with PNS compared to controls by -26.7 events/hour with 95% confidence interval and P value of [CI (-31.99, -21.46), I2 85, p 0.00]. The mean difference in central apnea index was -22.47 [CI (-25.19, -19.76), I2 0, p 0.00]. The mean reduction in the oxygen desaturation index of 4% or more demonstrated a decrease in PNS group by -24.16 events/hour [(CI -26.20, -22.12), I2 0, p 0.00] compared with controls. PNS resulted in mean reduction in arousal index of -13.77 [CI (-16.15, -11.40), I2 0, p 0.00]. The mean change in percent of time spent in rapid eye movement sleep demonstrated a nonsignificant increase in PNS group by 1.01 % [CI (-5.67, 7.86), I293, p 0.75]. In conclusion, PNS therapy for treating CSA demonstrated positive outcomes but larger randomized studies are needed to evaluate the safety and clinical outcomes.

Percutaneous left ventricular assist device support during ablation of ventricular tachycardia: A meta-analysis of current evidence.

INTRODUCTION: Catheter ablation of ventricular tachycardia (VT) can be an effective therapy to reduce VT burden, but often it is limited by the potential for hemodynamic instability. Percutaneous left ventricular assist devices (pLVADs) have been used to maintain hemodynamic support during VT ablation but the evidence regarding its clinical impact has been inconclusive. METHODS AND RESULTS: We sought to assess the clinical impact of pLVAD when used in VT ablation by conducting a meta-analysis of the current evidence. We searched Pubmed and found nine observational studies that compared clinical outcomes of VT ablation in patients with pLVAD support to controls with no pLVAD support. The pooled data did not show a significant difference in mortality between both groups, nor a difference in acute procedural success or in recurrence of VT. There was also no difference in the number of patients receiving a cardiac transplant or being enrolled in the transplant list. Although there was no difference in the ablation time between the groups, patients in the pLVAD group had a longer total procedural time and more procedure-related adverse effects. CONCLUSION: This meta-analysis did not show clinical benefits from using pLVAD support during VT ablation, whereas it was associated with longer procedure times and more complications. This study was, however, limited by the observational nature of the data. In view of these data, the risk and benefit of pLVAD support during VT ablation should be considered on an individual basis.

Identification and Ablation of Dormant Conduction in Atrial Fibrillation Using Adenosine.

BACKGROUND: Ablation is used for treatment of atrial fibrillation (AF) but recurrence is common. Dormant conduction is hypothesized to be responsible for these recurrences, and the role of adenosine in identification and ablation of these pathways is controversial with conflicting results on AF recurrence. MATERIALS AND METHODS: We conducted a meta-analysis for studies evaluating AF ablation and adenosine use. Included in the meta-analysis were human studies that compared ablation using adenosine or adenosine triphosphate (ATP) and reported freedom from AF in patients beyond a minimum follow-up of 6 months. RESULTS: Our analysis suggests that the use of adenosine leads to a decrease in recurrence of AF compared to the cohort which did not utilize adenosine. Subgroup analysis showed no difference in the recurrence of AF with the modality used for ablation (cryoablation vs. radiofrequency ablation) or with the preparation of adenosine used (ATP vs. adenosine). There was a significant benefit in delayed administration of ATP over early administration. Pooling results of only randomized control trials did not show any significant difference in AF recurrence. CONCLUSIONS: Adenosine-guided identification and ablation of dormant pathways may lead to a decrease in recurrence of AF.

Risk of Ischemic Heart Disease in Patients With Sjögren's Syndrome.

BACKGROUND: Ischemic heart disease (IHD) has emerged as a major cause of morbidity and mortality in patients with autoimmune conditions such as systemic lupus erythematosus and rheumatoid arthritis, but the risk of IHD in Sjögren's syndrome (SjS) is unknown. To fill this knowledge gap, we estimated the prevalence and risk of IHD with SjS compared to controls from the general population using the Healthcare Cost and Utilization Project National Inpatient Sample 2011 database. MATERIALS AND METHODS: The Healthcare Cost and Utilization Project administrative longitudinal database contains encounter-level information on inpatient stays, emergency department visits and ambulatory surgery in all U.S. hospitals. We conducted a cross-sectional study among the inpatient population diagnosed with SjS and matched 1:4 with controls for age, sex and hospital region. Odds ratio for IHD was calculated as cases compared to controls. The contribution of various risk factors to IHD was also evaluated by logistic regression. RESULTS: Analysis demonstrated that 7,154 of 13,086 cases (54.7%) of SjS had IHD compared to 27,367 of 52,448 controls (52.2%). The adjusted odds ratio for IHD in those with SjS was 0.898 (95% CI: 0.844-0.955). Patients with SjS were significantly more likely to have hypertension, diabetes, apnea and lipid disorders. CONCLUSIONS: To our knowledge, this is the largest population-based study investigating the risk of IHD in patients with SjS. We found a modest, though statistically significant, decrease in the risk of IHD in SjS compared to controls.