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.

Modes of death and clinical outcomes in adult patients with hypertrophic cardiomyopathy in Thailand.

BACKGROUND: There are limited data about modes of death and major adverse cardiovascular events (MACEs) in patients with hypertrophic cardiomyopathy (HCM) in South East Asian population. The aim of the study was to examine modes of death and clinical outcomes in Thai patients with HCM. METHODS: Between January 1, 2009 and December 31, 2013, 166 consecutive patients with HCM diagnosed in our institution were evaluated. Five patients were excluded because of non-Thai ethnic groups (n = 3) and diagnosis of myocardial infarction at initial presentation documented by coronary angiography (n = 2). The final study population consisted of 161 patients with HCM. HCM-related deaths included: (1) sudden cardiac death (SCD) - death due to sudden cardiac arrest or unexpected sudden death; (2) heart failure - death due to refractory heart failure; or (3) stroke - death due to embolic stroke associated with atrial fibrillation. MACEs included: (1) SCD, sudden unexpected aborted cardiac arrest, fatal, or nonfatal ventricular arrhythmia (ventricular fibrillation or sustained ventricular tachycardia); (2) heart failure (fatal or non-fatal), or heart transplantation; or (3) stroke - fatal or non-fatal embolic stroke associated with atrial fibrillation. RESULTS: One hundred and sixty-one Thai patients with HCM (age 66 ± 16 years, 58% female) were enrolled. Forty-two patients (26%) died over a median follow-up period of 6.8 years including 25 patients (16%) with HCM-related deaths (2%/year). The HCM-related deaths included: heart failure (52% of HCM-related deaths; n = 13), SCD (44% of HCM-related deaths; n = 11), and stroke (4% of HCM-related deaths, n = 1). The SCDs occurred in 6.8% of patients (1%/year). Eighty-four major MACEs occurred in 65 patients (41, 5%/year). The MACEs included: 40 heart failures in which 2 patients underwent heart transplants; 22 SCDs and nonfatal ventricular arrhythmias; and 22 fatal or nonfatal strokes. CONCLUSIONS: The most common mode of death in adult patients with HCM in Thailand was heart failure followed by SCD. About one-third of the patients experiencing heart failure died during the 6.8 years of follow-up. SCDs occurred in 7% of patients (1%/year), predominantly in the fourth decade or later.

Newer technologies for detection of atrial fibrillation.

Atrial fibrillation is a common arrhythmia that is associated with increased risk of stroke, which can be reduced with appropriate anticoagulation treatment. However, it remains underdiagnosed in contemporary clinical practice using conventional detection methods, resulting in missed opportunities to implement appropriate treatment. Newer technologies developed in recent years can potentially enhance the detection of atrial fibrillation and overcome certain limitations of the conventional methods. However, uncertainties remain about their use and the significance of atrial fibrillation detected by some of these newer technologies. This review examines the evidence supporting the use of some of these technologies and evaluates their applications in certain clinical scenarios.

Important Parameters for Implantable Cardioverter Defibrillator Selection.

The efficacy of implantable cardioverter defibrillators in reducing the risk of sudden cardiac death has been well established by several clinical trials. Several factors relating to device characteristics, patient attributes, and comorbidities should be considered when selecting the appropriate implantable cardioverter defibrillators for each patient. This review examines some of these issues.

Non-Classical Monocytes and Monocyte Chemoattractant Protein-1 (MCP-1) Correlate with Coronary Artery Calcium Progression in Chronically HIV-1 Infected Adults on Stable Antiretroviral Therapy.

BACKGROUND: Persistent inflammation and immune activation has been hypothesized to contribute to increased prevalence of subclinical atherosclerosis and cardiovascular disease (CVD) risk in patients with chronic HIV infection. In this study, we examined the correlation of peripheral monocyte subsets and soluble biomarkers of inflammation to coronary artery calcium (CAC) progression, as measured by cardiac computed tomography scan. METHODS: We conducted a longitudinal analysis utilizing baseline data of 78 participants with HIV infection on stable antiretroviral therapy (ART) in the Hawaii Aging with HIV-Cardiovascular study who had available baseline monocyte subset analysis as well as CAC measurement at baseline and at 2-year follow up. Monocyte phenotypes were assessed from cryopreserved blood by flow cytometry and plasma was assayed for soluble biomarkers using antibody-coated beads in a high sensitivity Milliplex Luminex platform. Change in CAC over 2 years was analyzed as the primary outcome variable. RESULTS: Of all monocyte subsets and biomarkers tested, higher non-classical monocyte percentage (ρ = 0.259, p = 0.022), interleukin (IL)-6 (ρ = 0.311, p = 0.012), and monocyte chemoattractant protein (MCP)-1 (ρ = 0.524, p = <0.001) were significantly correlated to higher 2-year CAC progression in unadjusted Spearman's correlation. Non-classical monocyte percentage (ρ = 0.247, p = 0.039), and MCP-1 (ρ = 0.487, p = <0.001), remained significantly correlated to 2-year CAC progression, while IL-6 was not (ρ = 0.209, p = 0.120) after adjustment for age, hypertension, diabetes mellitus, total/HDL cholesterol ratio, smoking history, and BMI. CONCLUSION: The percentage of non-classical monocytes and plasma MCP-1 levels were independently associated with CAC progression and may be related to the progression of atherosclerosis and increased CVD risk associated with chronic HIV infection on stable ART.

Serum amyloid P (SAP) is associated with impaired brachial artery flow-mediated dilation in chronically HIV-1 infected adults on stable antiretroviral therapy.

OBJECTIVE: This study aimed to evaluate the relationship between inflammatory biomarkers and endothelial dysfunction (ED), as measured by brachial artery flow-mediated dilation (FMD). METHODS: We conducted a cross-sectional analysis utilizing baseline data of 135 participants with HIV infection on stable antiretroviral therapy (ART) in the Hawaii Aging with HIV-Cardiovascular (HAHC-CVD) study who had available baseline inflammatory biomarkers and brachial artery FMD measurements. RESULTS: We observed significant associations between brachial artery FMD and baseline brachial artery diameter, age, male gender, traditional cardiovascular disease (CVD) risk factors such as BMI, waist to hip ratio, hypertension, systolic blood pressure (BP), diastolic BP, and LDL cholesterol, and 10-year coronary heart disease (CHD) risk estimated by Framingham risk score (FRS). Of all biomarkers tested, higher level of C-reactive protein (CRP) (beta = - 0.695, P = 0.030) and serum amyloid P (SAP) (beta = - 1.318, P = 0.021) were significantly associated with lower brachial artery FMD in univariable regression analysis. After adjusting for baseline brachial artery diameter, age, and selected traditional CVD risk factors in multivariable model, SAP remained significantly associated with brachial artery FMD (beta = - 1.094, P = 0.030), while CRP was not (beta = - 0.391, P = 0.181). DISCUSSION: Serum amyloid P was independently associated with impaired brachial artery FMD and may potentially relate to ED and increased CVD risk in HIV-infected patients on stable ART.

Granulomatosis with Polyangiitis: A Case of Nasal Mass, Necrotic Lung, and Normal Kidneys.

A diagnosis of granulomatosis with polyangiitis (GPA) can be challenging given various clinical manifestations. We report an incident case of GPA presenting with chronic sinusitis and mimicking an early lung abscess without renal involvement. A 51 year-old woman with chronic obstructive sinusitis presented with subacute dyspnea, pleuritic chest pain and fever. Physical examination revealed a right nasal mass without discharge or bleeding. Decreased to absent breath sounds and dullness to percussion were noted at the left lung base. Laboratory findings were significant for leukocytosis but normal renal function. The chest CT demonstrated dense consolidation with hypo-enhancement of the lingula. The sinus CT revealed an enhancing mass in the right nasal cavity and anterior ethmoid sinuses with associated bony destruction. Patient did not improve with empiric antibiotics for lung abscess. Aspiration of the lingular fluid showed purulent material, however, microbes did not grow in culture. A positive C-ANCA screen was confirmed. A right nasal biopsy was performed which revealed granulomatous inflammation with focal necrosis and vasculitis. The final diagnosis was GPA. Given various clinical manifestations, the diagnosis of GPA can be difficult to distinguish from infectious etiologies. This can delay the treatment, which may be life-saving and organ sparing. We emphasize that an initial screening ANCA serology test is recommended in patients with suggestive clinical findings of GPA. Biopsy of an affected organ is paramount for the definitive diagnosis.