Clinical implementation of guidelines for cardioverter defibrillator implantation: lost in translation?

Purpose: Guidelines for implantation of cardioverter defibrillators (ICD) are increasingly including indications for primary prevention of sudden cardiac death in high-risk groups, where ICDs were traditionally implanted for secondary prevention. We performed a single-centre audit to evaluate adherence to the recent Dutch guidelines. Methods: All 1886 patients visiting a large regional Dutch teaching hospital (attending 1.8 to 2.0% of the Dutch population) in November 2005 were screened using the recently updated Dutch guidelines. Patients fulfilling these criteria were categorised as having an ICD indication for primary or secondary prevention. Results: 135 patients had an indication for ICD, 19 of whom had one or received one. Of the remaining 116 patients, 14 were ‘new’ to the department of cardiology. The 102 ‘known’ patients had 466 doctor-patient contacts in the previous year, which averages 4.57 cardiology contacts per patient per year. Patients were more likely to receive an ICD for the secondary prevention of SCD (10/11, 91%) than for primary prevention (9/124, 7%). Conclusion: In a large regional teaching hospital in the Netherlands, only a small proportion of patients eligible for ICD implantation actually receive one. Cardiologists tend to implant ICDs for secondary prevention of SCD. The low ICD implantation rate for primary prevention of SCD may relate to logistics (e.g. permission to implant ICDs, the presence of an electrophysiology lab) or the perceived low cost-benefit ratio. Our results indicate that once the substantial backlog (13,500 ICDs) has been addressed, the annual implantation of new ICDs should rise from the current 125 to at least 510 per million inhabitants per year in the Netherlands. (Neth Heart J 2007;15:129-32.)     

A Study of Unusual Pacemaker Infection by Mycobacterium Tuberculosis in Indian Patients

Background

The expanding clinical indications of cardiac rhythm management have led to an increased use of pacemaker implantation which is associated with increased incidence of pacemaker infections. Staphylococcus aureus and epidermidis account for the vast majority of pacemaker infections. Pacemaker infection due to Mycobacterium tuberculosis (M. tuberculosis) is very rare, only few cases having been reported till date.

Methods

We describe here a study of three patients of pacemaker pocket infection with M. tuberculosis.

Conclusion

The possibility of mycobacterial pacemaker infection should always be kept in mind in patients with delayed pacemaker infection.     

Comparison of complications and shocks in paediatric and young transvenous and subcutaneous implantable cardioverter-defibrillator patients

Background

Young implantable cardioverter-defibrillator (ICD) patients are prone to complications and inappropriate shocks (IAS). The subcutaneous ICD (S-ICD) may avoid lead-related complications. This study aims to describe the incidence and nature of device-related complications in young transvenous ICD (TV-ICD) and S?ICD patients.

Methods

Single-chamber TV-ICD and S?ICD patients up to and including the age of 25 years implanted between 2002 and 2015 were retrospectively analysed. Complications were defined as device-related complications requiring surgical intervention. IAS were defined as shocks for anything other than ventricular tachycardia or ventricular fibrillation. Follow-up data were collected 5 years post-implantation. Kaplan-Meier estimates for complications at 5?year follow-up were calculated with a corresponding 95% confidence interval.

Results

Eighty-one patients (46 TV-ICD, 35 S-ICD) were included (median age 19.0 (IQR 16.0–23.0) and 16.5 (IQR 13.0–20.2) years respectively). Median follow-up was 60 and 40 months respectively. All-cause complication rate was 34% in the TV-ICD group and 25% in the S?ICD group (p?=?0.64). TV-ICD patients had more lead complications: 23% (10–36%) versus 0% (p?=?0.02). The rate of infections did not differ between TV-ICD and S?ICD: 2% (0–6%) versus 10% (0–21%) (p?=?0.15). No systemic infections occurred in the S?ICD patients. The rates of IAS were similar, TV-ICD 22% (9–35%) versus S?ICD 14% (0–30%) (p?=?0.40), as were those for appropriate shocks: 25% (11–39%) versus 27% (6–48%) (p?=?0.92).

Conclusion

The rates of all-cause complications in this cohort were equal, though the nature of the complications differed. S?ICD patients did not suffer lead failures or systemic infections. An era effect is present between the two groups.

     

Incidence of lead dislodgement,malfunction and perforation during the first year following device implantation

Background

The number of cardiac rhythm device implantations has been growing fast due to expanding indications and ageing of the population. Complications of implantation were rare in the trials. However, these involved small numbers and selected patients. Prospective real-life data are necessary to assess cardiac device implantation procedure-related risks.

Objective

To determine the incidence and predictors of lead-related re-intervention in a Dutch high-volume teaching hospital.

Methods

Data from all patients who underwent cardiac rhythm device implantation between January 2010 and December 2011 were collected in a prospective registry. At least 1 year of follow-up regarding re-intervention was available for all patients. Lead-related reasons for re-intervention were categorised into lead dislodgement, malfunctioning or perforation.

Results

One thousand nine hundred twenty-nine devices including 3909 leads were implanted. In 595 patients (30.8 %) a CRT-D/P was implanted. Lead-related re-intervention was necessary in 86 (4.4 %) patients; it was more common in younger and male patients, and due to either lead dislodgement (66 %), malfunctioning (20 %) or perforation (18 %). Coronary sinus lead dislodgement or malfunctioning was 1.4 %. Right atrial dislodgement (1.9 %, p < 0.001) or ICD lead dislodgement (1.8 %, p = 0.002) was more common than right ventricular dislodgement (0.3 %). The incidence of lead malfunctioning was higher (0.8 %) in ICD leads. An apical position of the right ventricular lead and lateral wall position of the right atrial lead were related to cardiac perforation.

Conclusions

The incidence of lead-related re-intervention was comparable with the literature. The majority of re-interventions were due to lead dislodgements, particularly with right atrial and ICD leads. Re-intervention due to coronary sinus lead dislodgement was rare.     

Pacemaker pocket infection by Nocardia carnea. First case description and literature review

Acid-fast gram-positive bacilli are a seldom causal agent of cardiac implantable electronic devices (CIED) infections. A pacemaker pocket infection by Nocardia carnea is presented. The objective of this review is to know the incidence of pacemaker pocket infection by Nocardia and to collect information to contribute to the management of this infection. We describe both our case and those found in the literature. Only three cases were found. Two of the patients were older than 70 years without immunosuppression, presenting erythema at the pacemaker implantation site as main symptom. Bloodstream infection was registered in one of them. Three microorganisms were sensitive to cotrimoxazole. The minimum time of antibiotic therapy was 6 weeks. An incomplete device removal was done in one case, resulting in an unfavorable clinical course. The incidence of pacemaker pocket infection by these microorganisms is low, resolved in most cases with antibiotic treatment and device removal.     

Implantable Cardioverter Defibrillators in Octogenarians: Clinical Outcomes From a Single Center

AimsLimited data exist on outcomes in very elderly ICD recipients. We describe outcomes in new ICD and Cardiac Resynchronisation Therapy with Defibrillator (CRT-D) implants in octogenarians at our institution.MethodsPatients aged 80 years and above who underwent de novo ICD or CRT-D implantation from January 2006 to July 2012 were identified. Clinical data were collected from the procedural record, medical and ICD notes. Baseline characteristics were compared using independent sample t test for continuous variables and Fisher’s exact test for categorical variables. Kaplan-Meier curves were constructed.ResultsTen per cent of all new ICD/CRT-D implants were aged 80 years and over. Median age was 83.0 years. Median follow-up was 29 months. Death occurred in 17 (34%). Median time to death was 23 months. Three deaths (6%) occurred within 12 months of ICD implantation. Appropriate therapy (ATP or shock) occurred in 19 (38%). Inappropriate therapy occurred in 6 (12%).Rates of appropriate shocks and inappropriate therapy (shocks and ATP) and significant valvular incompetence were higher amongst deceased patients (P=0.03 OR 5.9 95% CI 1.3-27) and (P=0.02 OR 12 95% CI 1.3-112). Univariate analysis identified diuretic use (P=0.008 95% C.I. 0.05 to 0.63) and appropriate shock (P= 0.025 95% C.I. 1.25 to 26.3) as predictors of mortality.ConclusionOctogenarians make up a small but increasing number of ICD recipients. This study highlights high survival rates at one year with acceptable rates of appropriate and inappropriate device therapy. Ongoing debate regarding the appropriateness of ICD in very elderly patients is warranted.Key words: sudden cardiac death, implantable defibrillators, octogenarians     

Under-Utilization of Implantable Cardioverter Defibrillators in Patients with Heart Failure - The Current State of Sudden Cardiac Death Prophylaxis

BackgroundDespite ACC/AHA guidelines indicating implantable cardioverter defibrillator (ICD) as class I therapy for primary prevention of sudden cardiac death in patients with EF≤35%, ICD utilization rates in real world practice have been low.ObjectiveTo determine the rate of ICD implantation at a tertiary care academic center and to assess the reasons for under-utilization of the same.MethodsReview of a prospectively collected database which included all patients diagnosed with an EF≤35% was performed to assess the rate of ICD implantation and mortality. Reasons for non-implantation of ICD were then assessed from detailed chart review.ResultsA total of 707 patients (age 69.4 ± 14.1 years) with mean EF of 26±7% were analyzed. Only 28% (200/707) of patients had ICDs implanted. Mortality was lower in the group with ICD (25% vs 37%, p=0.004). When patients who either died or were lost to follow-up prior to 2005 were excluded, ICD utilization rate was still low at 37.6%. The most common reason for non-implantation of ICD was physicians not discussing this option with their patients. Patient refusal was the second most common reason.ConclusionsICD Implantation rates for primary prevention of SCD in patients with EF≤35% is low. Physician and patient education should be addressed to improve the utilization rates.Key words: Implantable cardioverter-defibrillator, Outcomes, sudden cardiac death     

Cardiac sympathetic activity in chronic heart failure: cardiac <Superscript>123</Superscript>I-<Emphasis Type="Italic">m</Emphasis>IBG scintigraphy to improve patient selection for ICD implantation

Heart failure is a life-threatening disease with a growing incidence in the Netherlands. This growing incidence is related to increased life expectancy, improvement of survival after myocardial infarction and better treatment options for heart failure. As a consequence, the costs related to heart failure care will increase. Despite huge improvements in treatment, the prognosis remains unfavourable with high one-year mortality rates. The introduction of implantable devices such as implantable cardioverter defibrillators (ICD) and cardiac resynchronisation therapy (CRT) has improved the overall survival of patients with chronic heart failure. However, after ICD implantation for primary prevention in heart failure a high percentage of patients never have appropriate ICD discharges. In addition 25–50?% of CRT patients have no therapeutic effect. Moreover, both ICDs and CRTs are associated with malfunction and complications (e.?g. inappropriate shocks, infection). Last but not least is the relatively high cost of these devices. Therefore, it is essential, not only from a clinical but also from a socioeconomic point of view, to optimise the current selection criteria for ICD and CRT. This review focusses on the role of cardiac sympathetic hyperactivity in optimising ICD selection criteria. Cardiac sympathetic hyperactivity is related to fatal arrhythmias and can be non-invasively assessed with ¹²³I-meta-iodobenzylguanide (¹²³I-mIBG) scintigraphy. We conclude that cardiac sympathetic activity assessed with ¹²³I-mIBG scintigraphy is a promising tool to better identify patients who will benefit from ICD implantation.     

Prospective Study of Leptospirosis Transmission in an Urban Slum Community: Role of Poor Environment in Repeated Exposures to the Leptospira Agent

Background

Leptospirosis has emerged as an urban health problem as slum settlements have rapidly spread worldwide and created conditions for rat-borne transmission. Prospective studies have not been performed to determine the disease burden, identify risk factors for infection and provide information needed to guide interventions in these marginalized communities.

Methodology/Principal Findings

We enrolled and followed a cohort of 2,003 residents from a slum community in the city of Salvador, Brazil. Baseline and one-year serosurveys were performed to identify primary and secondary Leptospira infections, defined as respectively, seroconversion and four-fold rise in microscopic agglutination titers. We used multinomial logistic regression models to evaluate risk exposures for acquiring primary and secondary infection. A total of 51 Leptospira infections were identified among 1,585 (79%) participants who completed the one-year follow-up protocol. The crude infection rate was 37.8 per 1,000 person-years. The secondary infection rate was 2.3 times higher than that of primary infection rate (71.7 and 31.1 infections per 1,000 person-years, respectively). Male gender (OR 2.88; 95% CI 1.40–5.91) and lower per capita household income (OR 0.54; 95% CI, 0.30–0.98 for an increase of $1 per person per day) were independent risk factors for primary infection. In contrast, the 15–34 year age group (OR 10.82, 95% CI 1.38–85.08), and proximity of residence to an open sewer (OR 0.95; 0.91–0.99 for an increase of 1 m distance) were significant risk factors for secondary infection.

Conclusions/Significance

This study found that slum residents had high risk (>3% per year) for acquiring a Leptospira infection. Re-infection is a frequent event and occurs in regions of slum settlements that are in proximity to open sewers. Effective prevention of leptospirosis will therefore require interventions that address the infrastructure deficiencies that contribute to repeated exposures among slum inhabitants.     

Calodium hepaticum: Household Clustering Transmission and the Finding of a Source of Human Spurious Infection in a Community of the Amazon Region

Background: Calodium hepaticum (syn. Capillaria hepatica) is a worldwide helminth parasite of which several aspects of transmission still remain unclear. In the Amazon region, the mechanism of transmission based on the ingestion of eggs present in the liver of wild mammals has been suggested as the cause of the spurious infections described. We performed an epidemiological investigation to determine the incidence, risk of spurious infection and the dynamics of transmission of C. hepaticum in a community of the Brazilian Amazon. Methodology/Principal Findings: Stool samples of 135 individuals, two dog feces and liver tissue from a peccary (captured and eaten by the residents) were analyzed by conventional microscopy. Dog feces were collected from the gardens of households presenting human cases of spurious C. hepaticum infections. Community practices and feeding habits related to the transmission of the parasite were investigated. The individual incidence of spurious infection was 6.7% (95% CI: 2.08–11.24). Cases of spurious infection were observed in 7.5% of the families and the household incidence was from 50% to 83.3%. The risk of spurious infection was 10-fold greater in persons consuming the liver of wild mammals (p = 0.02). The liver tissue of a peccary and one feces sample of a dog presented eggs of C. hepaticum. The consumption of the infected liver was the cause of the spurious infections reported in one household. Conclusions/Significance: This is the first identification of a source of spurious infection by C. hepaticum in humans and we describe a high rate of incidence in household clusters related to game liver alimentary habits. The finding of a dog feces contaminating peridomiciliary ground suggests the risk of new infections. We conclude that the mechanism of transmission based on the ingestion of liver is important for the dynamics of transmission of C. hepaticum in the studied area.     

Life-threatening perforation of a defibrillation lead

We describe cardiac perforation of a Riata implantable cardioverter defibrillator (ICD) shock lead in a 76-year-old male nine days after implantation of a prophylactic ICD. Since there are more reports of increased risk of cardiac perforations with the Riata lead, we advise cautious use of this lead. (Neth Heart J 2009;17:113–4.)     

First experience with the wearable cardioverter defibrillator in the Netherlands

The implantable cardioverter defibrillator (ICD) has significantly improved survival in patients with an increased risk of sudden cardiac death (SCD). The wearable cardioverter defibrillator (WCD) is an alternative to the ICD in patients with a transient ICD indication or those in whom an ICD temporarily cannot be implanted. We describe here the technical details of the WCD and report three patients who were treated with a WCD in an outpatient setting. The WCD allowed the cardiac condition of two patients to improve to such an extent that permanent ICD implantation was deemed unnecessary. This new form of therapy may result in significant cost reduction, avoidance of unnecessary ICD implantation, and increased patient satisfaction.     

Association between inflammatory gene polymorphisms and the risk of myocardial infarction

Allele and genotype frequency distributions of polymorphism rs2076059 (3832T>C) within the SELE gene, rs6131 (S290N), within the SELP gene, rs1131498 (F206L), within the SELL gene, rs5498 (K469E) within the ICAM1 gene, rs35569394 (?2549(18)I/D) within the VEGFA gene, and rs1024611 (?2518A>G) within the CCL2 gene were examined in a group of patients after myocardial infarction (MI)(280 individuals) and in a control group (312 individuals). An implementation of the Markov chain and Monte-Carlo method (APSampler) revealed the allele combinations associated with decreased and increased risk of MI. Among these, the most important allele combinations were SELE*C + SELP*S + CCL2*A (FDR = 0.0005; OR = 0.42), SELP*S + CCL2*A (FDR = 0.0009; OR = 0.36), SELL*F + VEGFA*I + CCL2*G/G (FDR = 0.0009; OR = 4.17), VEGFA*I + CCL2*G/G (FDR = 0.0009; OR = 3.76), SELE*C + CCL2*A (FDR = 0.0023; OR = 0.47), and SELL*F + CCL2*G/G (FDR = 0.003; OR = 3.15).     

Device updates successfully reduce T‑wave oversensing and inappropriate shocks in subcutaneous ICD patients

Aims

To analyse the impact of device and software updates on the prevention of T?wave oversensing (TWOS) and inappropriate shocks (IS) in subcutaneous ICD (S-ICD) patients.

Background

TWOS is a feared complication after implantation. It may lead to harmful IS. To date, specific strategies to reduce these events are lacking.

Methods

In this retrospective single-centre trial we analysed 146 S?ICD patients who were implanted between 2010 and 2016. In all eligible consecutive patients (n?=?139), follow-up of at least 6 weeks was studied. The incidence of TWOS/IS was analysed in patients receiving a 2^nd generation S?ICD (Emblem-S-ICD) between 2014 and 2016 (Emblem). Their outcome was compared with a control group (SQ) treated with the SQ1010 device between 2010 and 2014, who were followed up for a maximum of 2 years. Furthermore, to test if the software update SMR8 reduces inappropriate shocks in the SQ1010-S-ICD population, the incidence of TWOS/IS was evaluated before and after update installation.

Results

Basic characteristics and indications for S?ICD implantation were similar in both groups. However, the cumulative incidence of TWOS/IS was significantly decreased in Emblem vs. SQ (SQ: 15.4%, n?=?14/91 vs. Emblem 4.2%, n?=?2/48; p?=?0.049). Furthermore, with regards to the SQ population we also observed a trend towards a significant reduction of TWOS/IS after installation of the software update SMR8 in 2014 (before update: 13.4%, n?=?11/82 vs. after update: 4.6%, 3/65, p?=?0.07).

Conclusion

2^nd generation devices but probably also the SMR8 software update reduce the incidence of TWOS/IS in S?ICD patients.

     

Factors Influencing Utilization of the Primary Prevention Implantable Defibrillator

Background

A growing literature suggests underutilization of the primary prevention implantable cardioverter-defibrillator (ICD); thus, factors influencing utilization need to be understood. We performed a comprehensive assessment of patient characteristics and health insurance status among subjects eligible for primary prevention ICD in a tertiary care center.

Methods

From among a group of patients who met criteria for primary prevention ICD based on left ventricular dysfunction (LVEF ≤ 35%), ICD recipients (n = 110) were compared to ICD non-recipients (n = 110) to identify determinants of ICD implantation. We evaluated demographics, clinical profile including Charlson Comorbidity Index [CCI, categorized as low (≤3) or high (>3)] and health insurance status.

Results

ICD recipients were younger (62.1±15.0 vs. 68.0±18.2; P = 0.01), with more males (80% vs. 65.5%; P = 0.01), higher NYHA class (II/III: 75.5% vs. 40.2%; P<0.001) and more likely to have supplemental private health insurance (61.8% vs. 46.4%; P = 0.02). CCI was not significantly different between the two groups (low CCI 61.8% vs. 62.7%; P = 0.89). In multivariable analysis, factors independently associated with ICD implantation were male sex (OR, 2.77, [1.31-5.85]; P = 0.01), age<75 (OR, 2.68, [1.30-5.50]; P = 0.01), private insurance (OR, 2.17, [1.08-4.36], P = 0.03) and NYHA Class II/III (OR, 5.91, [2.91-12.01]; P<0.001). Documentation of discussion about primary prevention ICD was absent in the majority (57.2%) of non-recipients.

Conclusion

In a contemporary urban tertiary care setting, age, sex and heart failure symptom class were associated with ICD utilization, with socioeconomic/insurance status also potentially playing a role. These findings have implications for optimizing appropriate utilization of the prophylactic ICD and warrant follow-up in larger, more diverse populations.     

The efficacy of the LinoxSmart DX ICD lead from a single center experience

PurposeThe Biotronik Linox^Smart DX implanted cardioverter defibrillator (ICD) lead is a novel VDD lead with the advantage of integrated atrial sensing dipole combined with a special augmentation and filtering mechanisms. We sought to determine the efficacy of the Biotronik Linox^Smart DX ICD lead.MethodsNon-randomized consecutive patients implanted with Biotronik Linox^Smart DX lead at Sheba Medical Center were included in this study. Electrical parameters and arrhythmic events were recorded during follow up of one year.ResultsSeventy-three patients (69 males (94.5%), mean age 61 ± 12 years) were included. All patients were successfully implanted with a Biotronic VR-T DX device and Linox^Smart DX ICD lead (DX-17 in 37% and DX-15 in 63% patients). Mean P wave amplitude at time of implantation was 3.66 ± 2.9 mV and improved significantly throughout the follow-up (5.29 ± 4.39 mV, p = 0.009). Appropriate atrial sensing (defined as P wave amplitude of ≥0.8 mV) rate of 100% at implantation significantly decreased to 89% (p = 0.015) at 12 months. Three out of 67 (4.5%) patients without a known history of atrial fibrillation had documented new onset paroxysmal atrial fibrillation. Appropriate shocks occurred in 4 (5.5%) patients. One patient with atrial sensing less than 0.4 mV had inappropriate shock.ConclusionsAmong patients implanted with the Biotronik Linox^Smart DX ICD lead in our single center, appropriate atrial sensing rate decreased over 12 months. Larger studies are needed to evaluate the reliability of long term appropriate atrial sensing.     

Incidence and predictors of phantom shocks in implantable cardioverter defibrillator recipients

Background

Implantable cardioverter defibrillators (ICDs) are designed to deliver shocks or antitachycardia pacing (ATP) in the event of ventricular arrhythmias. During follow-up, some ICD recipients experience the sensation of ICD discharge in the absence of an actual discharge (phantom shock). The aim of this study was to evaluate the incidence and predictors of phantom shocks in ICD recipients.

Methods

Medical records of 629 consecutive patients with ischaemic or dilated cardiomyopathy and prior ICD implantation were studied.

Results

With a median follow-up of 35 months, phantom shocks were reported by 5.1 % of ICD recipients (5.7 % in the primary prevention group and 3.7 % for the secondary prevention group; p=NS). In the combined group of primary and secondary prevention, there were no significant predictors of the occurrence of phantom shocks. However, in the primary prevention group, phantom shocks were related to a history of atrial fibrillation (p=0.03) and NYHA class <III (p=0.05). In the secondary prevention group, there were no significant predictors for phantom shocks.

Conclusion

Phantom shocks occur in approximately 5 % of all ICD recipients. In primary prevention patients, a relation with a history of atrial fibrillation and NYHA class <III were significant predictors for the occurrence of phantom shocks. In the secondary prevention patients, no significant predictors were found.     

TNF,IL6, and IL1B Polymorphisms Are Associated with Severe Influenza A (H1N1) Virus Infection in the Mexican Population

Background

Hypercytokinemia is the main immunopathological mechanism contributing to a more severe clinical course in influenza A (H1N1) virus infections. Most patients infected with the influenza A (H1N1) pdm09 virus had increased systemic levels of pro-inflammatory cytokines; including interleukin IL-6, IL-8, and tumor necrosis factor-alpha (TNF-α). We propose that single-nucleotide polymorphisms (SNPs) in the promoter regions of pro-inflammatory genes are associated with the severity of influenza A (H1N1) pdm09 virus infection.

Methods

145 patients with influenza A (H1N1) (pA/H1N1), 133 patients with influenza-like illness (ILI), and 360 asymptomatic healthy contacts (AHCs) were included. Eleven SNPs were genotyped in six genes (TNF, LT, IL1B, IL6, CCL1, and IL8) using real-time PCR; the ancestral genotype was used for comparison. Genotypes were correlated with 27 clinical severity variables. Ten cytokines (GM-CSF, TNF-α, IL-2, IL-1β, IL-6, IL-8, IFN-γ, IL-10, IL-5, and IL-4) were measured on a Luminex 100.

Results

The IL6 rs1818879 (GA) heterozygous genotype was associated with severe influenza A (H1N1) virus infection (odds ratio [OR] = 5.94, 95% confidence interval [CI] 3.05–11.56), and two IL1B SNPs, rs16944 AG and rs3136558 TC, were associated with a decreased risk of infection (OR = 0.52 and OR = 0.51, respectively). Genetic susceptibility was determined (pA/H1N1 vs. AHC): the LTA rs909253 TC heterozygous genotype conferred greater risk (OR = 1.9), and a similar association was observed with the IL1B rs3136558 CC genotype (OR = 1.89). Additionally, severely ill patients were compared with moderately ill patients. The TNF-238 GA genotype was associated with an increased risk of disease severity (OR = 16.06, p = 0.007). Compared with ILIs, patients with severe pA/H1N1 infections exhibited increased serum IL-5 (p <0.001) and IL-6 (p  =  0.007) levels.

Conclusions

The TNF gene was associated with disease severity, whereas IL1B and IL6 SNPs were associated with influenza A (H1N1) virus infection.     

Prognostic value of microvolt T-wave alternans in a real-world ICD population. Twente ICD Cohort Studie (TICS)

Introduction

Survival benefit from ICD implantation is relatively low in primary prevention patients. Better patient selection is important to maintain maximum survival benefit while reducing the number of unnecessary implants. Microvolt T-wave alternans (MTWA) is a promising risk marker. In this study, we aimed to evaluate the predictive value of MTWA in ICD patients.

Methods and results

This study was a substudy of the Twente ICD Cohort Study (TICS). Patients with ischaemic or non-ischaemic left ventricular dysfunction who received an ICD following current ESC guidelines were eligible for inclusion. Exercise-MTWA was performed and classified as non-negative or negative. The primary endpoint was the composite of mortality and appropriate shock therapy. Analysis was performed in 134 patients (81 % male, mean age 62 years, mean ejection fraction 26.5 %). MTWA was non-negative in 64 %. There was no relation between non-negative MTWA testing and mortality and/or appropriate shock therapy (all p-values >0.15). Due to clinical conditions, 24 % were ineligible for testing. These patients experienced the highest risk for mortality (p < 0.01).

Conclusion

Non-negative MTWA testing did not predict mortality and/or appropriate shock therapy. Furthermore, MTWA testing is not feasible in a large percentage of patients. These ineligible patients experience the highest risk for mortality.     

The epidemiology of soil-transmitted helminth infections in children up to 8 years of age: Findings from an Ecuadorian birth cohort

BackgroundThere are few prospective longitudinal studies of soil-transmitted helminth (STH) infections during early childhood. We studied the epidemiology of and risk factors for soil-transmitted helminth infections from birth to 8 years of age in tropical Ecuador.Methods2,404 newborns were followed to 8 years of age with periodic stool sample collections. Stool samples were collected also from household members at the time of the child’s birth and examined by microscopy. Data on social, environmental, and demographic characteristics were collected by maternal questionnaire. Associations between potential risk factors and STH infections were estimated using generalized estimated equations applied to longitudinal binary outcomes for presence or absence of infections at collection times.ResultsOf 2,404 children, 1,120 (46.6%) were infected with at least one STH infection during the first 8 years of life. The risk of A. lumbricoides (16.2%) was greatest at 3 years, while risks of any STH (25.1%) and T. trichiura (16.5%) peaked at 5 years. Factors significantly associated with any STH infection in multivariable analyses included age, day-care (OR 1.34, 95% CI 1.03–1.73), maternal Afro-Ecuadorian ethnicity (non-Afro vs. Afro, OR 0.55, 95% CI 0.43–0.70) and lower educational level (secondary vs. illiterate, OR 0.31, 95% CI 0.22–0.45)), household overcrowding (OR 1.53, 95% CI 1.21–1.94)), having a latrine rather than a water closet (WC vs. latrine, OR 0.77, 95% CI 0.62–0.95)), and STH infections among household members (OR 2.03, 95% CI 1.59–2.58)). T. trichiura was more associated with poverty (high vs. low socioeconomic status, OR, 0.63, 95% CI 0.40–0.99)] and presence of infected siblings in the household (OR 3.42, 95% CI 2.24–5.22).ConclusionSTH infections, principally with A. lumbricoides and T. trichiura, peaked between 3 and 5 years in this cohort of children in tropical Ecuador. STH infections among household members were an important determinant of infection risk and could be targeted for control and elimination strategies.