Outpatient treatment with the wearable cardioverter defibrillator: clinical experience in two Dutch centres

Introduction

The latest European Society of Cardiology Guidelines recommend consideration of a wearable cardioverter-defibrillator (WCD) for patients with a poor left ventricular ejection fraction (LVEF) who are at risk of sudden arrhythmic death but are not eligible for an implantable defibrillator. For these patients a WCD can be an alternative to long-term hospitalisation.

Purpose

To evaluate the use of WCD therapy in these patient groups in two Dutch centres.

Methods

All consecutive patients treated with the WCD between 2009 and 2016 were included from two centres in the Netherlands. Data on events and compliance were collected retrospectively through home monitoring systems and adjudicated by the investigators.

Results

A total of 79 patients were treated with a WCD. Common indications were newly diagnosed cardiomyopathy without optimal medical treatment in 46 patients (58.2%) and bridge to implantable cardioverter-defibrillator (ICD) implant in 33 patients (41.8%). Bridge to implant indications consisted of contraindications for immediate implantation such as infections (e.?g. previous device-related infections) and radiotherapy. Compliance was over 97% per day (median 23.3?h, 22.6–23.7), during a median of 79 days (50.0–109.8.0). Two patients (2.6%) received an appropriate shock (annual rate 13.6%), there was 1 (1.3%) inappropriate shock (annual rate 6.7%). In 24 patients (52.2%) without optimal medical treatment, the LVEF was sufficiently improved and ICD implant was avoided. Eight (10.1%) patients did not receive an ICD. In 45 patients an ICD was implanted (57.0%).

Conclusion

WCD therapy provides a safe and effective treatment in outpatient setting for patients at high risk for sudden cardiac death and reduces the number of ICDs implanted.

     

Dutch outcome in implantable cardioverter-defibrillator therapy (DO-IT): registry design and baseline characteristics of a prospective observational cohort study to predict appropriate indication for implantable cardioverter-defibrillator

Background

Implantable cardioverter-defibrillators (ICDs) are widely used for the prevention of sudden cardiac death. At present, both clinical benefit and cost-effectiveness of ICD therapy in primary prevention patients are topics of discussion, as only a minority of these patients will eventually receive appropriate ICD therapy.

Methods/design

The DO-IT Registry is a nationwide prospective cohort with a target enrolment of 1,500 primary prevention ICD patients with reduced left ventricular function in a setting of structural heart disease. The primary outcome measures are death and appropriate ICD therapy for ventricular tachyarrhythmias. Secondary outcome measures are inappropriate ICD therapy, death of any cause, hospitalisation for ICD related complications and for cardiovascular reasons. As of December 2016, data on demographic, clinical, and ICD characteristics of 1,468 patients have been collected. Follow-up will continue up to 24 months after inclusion of the last patient. During follow-up, clinical and ICD data are collected based on the normal follow-up of these patients, assuming ICD interrogations take place every six months and clinical follow-up is once a year. At baseline, the mean age was 66 (standard deviation [SD] 10) years and 27% were women.

Conclusion

The DO-IT Registry represents a real-world nationwide cohort of patients receiving ICDs for primary prevention of sudden cardiac death with reduced left ventricular function in a setting of structural heart disease. The registry investigates the efficacy of the current practice and aims to develop prediction rules to identify subgroups who will not (sufficiently) benefit from ICD implantation and to provide results regarding costs and budget impact of targeted supply of primary preventions ICDs.

     

Cardiac rehabilitation in patients who underwent primary percutaneous coronary intervention for acute myocardial infarction: determinants of programme participation and completion

Background

Hospital length of stay after acute myocardial infarction (AMI) treated with primary percutaneous coronary intervention (pPCI) has reduced, resulting in more limited patient education during admission. Therefore, systematic participation in cardiac rehabilitation (CR) has become more essential. We aimed to identify patient-related factors that are associated with participation in and completion of a CR programme.

Methods

We identified 3,871 consecutive AMI patients who underwent pPCI between 2003 and 2011. These patients were linked to the database of Capri CR, which provides dedicated, multi-disciplinary CR. ‘Participation’ was defined as registration at Capri CR within 6 months after pPCI. CR was ‘complete’ if a patient undertook the final exercise test.

Results

In total, 1,497 patients (39%) were registered at Capri CR. Factors independently associated with CR participation included age (<50 vs. >70 year: odds ratio (OR) 7.0, 95% confidence interval (CI) 5.1–9.6), gender (men vs. women: OR 1.9, 95% CI 1.3–1.8), index diagnosis (ST-elevation myocardial infarction [STEMI] vs. non-ST-elevation myocardial infarction [NSTEMI]: OR 2.4, 95% CI 2.0–2.7) and socio-economic status (high vs. low: OR 2.0, 95% CI 1.6–2.5). The model based on these factors discriminated well (c-index 0.75). CR programme completion was 80% and was inversely related with diabetes, current smoking and previous MI. The discrimination of the model based on these factors was poor (c-index 0.59).

Conclusions

Only a minority of AMI/pPCI patients participated in a CR programme. Completion rates, however, were better. Increased physician and patient awareness of the benefits of CR are still needed, with focus on the elderly, women and patients with low socio-economic status.

     

Magellanic penguin telomeres do not shorten with age with increased reproductive effort,investment, and basal corticosterone

All species should invest in systems that enhance longevity; however, a fundamental adult life‐history trade‐off exists between the metabolic resources allocated to maintenance and those allocated to reproduction. Long‐lived species will invest more in reproduction than in somatic maintenance as they age. We investigated this trade‐off by analyzing correlations among telomere length, reproductive effort and output, and basal corticosterone in Magellanic penguins (Spheniscus magellanicus). Telomeres shorten with age in most species studied to date, and may affect adult survival. High basal corticosterone is indicative of stressful conditions. Corticosterone, and stress, has been linked to telomere shortening in other species. Magellanic penguins are a particularly good model organism for this question as they are an unusually long‐lived species, exceeding their mass‐adjusted predicted lifespan by 26%. Contrary to our hypothesis, we found adults aged 5 years to over 24 years of age had similar telomere lengths. Telomeres of adults did not shorten over a 3‐year period, regardless of the age of the individual. Neither telomere length, nor the rate at which the telomeres changed over these 3 years, correlated with breeding frequency or investment. Older females also produced larger volume clutches until approximately 15 years old and larger eggs produced heavier fledglings. Furthermore, reproductive success (chicks fledged/eggs laid) is maintained as females aged. Basal corticosterone, however, was not correlated with telomere length in adults and suggests that low basal corticosterone may play a role in the telomere maintenance we observed. Basal corticosterone also declined during the breeding season and was positively correlated with the age of adult penguins. This higher basal corticosterone in older individuals, and consistent reproductive success, supports the prediction that Magellanic penguins invest more in reproduction as they age. Our results demonstrate that telomere maintenance may be a component of longevity even with increased reproductive effort, investment, and basal corticosterone.     

Nasal gene expression differentiates COPD from controls and overlaps bronchial gene expression

Background

Nasal gene expression profiling is a promising method to characterize COPD non-invasively. We aimed to identify a nasal gene expression profile to distinguish COPD patients from healthy controls. We investigated whether this COPD-associated gene expression profile in nasal epithelium is comparable with the profile observed in bronchial epithelium.

Methods

Genome wide gene expression analysis was performed on nasal epithelial brushes of 31 severe COPD patients and 22 controls, all current smokers, using Affymetrix Human Gene 1.0 ST Arrays. We repeated the gene expression analysis on bronchial epithelial brushes in 2 independent cohorts of mild-to-moderate COPD patients and controls.

Results

In nasal epithelium, 135 genes were significantly differentially expressed between severe COPD patients and controls, 21 being up- and 114 downregulated in COPD (false discovery rate?<?0.01). Gene Set Enrichment Analysis (GSEA) showed significant concordant enrichment of COPD-associated nasal and bronchial gene expression in both independent cohorts (FDR_GSEA <?0.001).

Conclusion

We identified a nasal gene expression profile that differentiates severe COPD patients from controls. Of interest, part of the nasal gene expression changes in COPD mimics differentially expressed genes in the bronchus. These findings indicate that nasal gene expression profiling is potentially useful as a non-invasive biomarker in COPD.

Trial registration

ClinicalTrials.gov registration number NCT01351792 (registration date May 10, 2011), ClinicalTrials.gov registration number NCT00848406 (registration date February 19, 2009), ClinicalTrials.gov registration number NCT00807469 (registration date December 11, 2008).

     

Effects of predation risk on the nocturnal activity budgets of thin-billed prions Pachyptila belcheri on New Island, Falkland Islands

Predation is a major ecological and evolutionary driver of natural populations, greatly influencing fitness and behaviour of prey species. Small, long-lived petrels are vulnerable to predation at the breeding colonies and are expected to evolve behavioural strategies to minimize predation risks. Using an automatic nest monitoring system and nightly aerial counts, we examined the effect of vegetation cover and moonlight on colony attendance patterns and levels of burrow activity of breeding thin-billed prions, Pachyptila belcheri, on New Island, Falkland Islands. We further investigated how these parameters were related to predation by Falkland skuas. We monitored up to 32 nests in two habitats, one with Tussock grass and one with low vegetation cover. Individuals in both areas were more active at the nest before hatching, and those breeding in the low cover habitat were more active and arrived at the colony earlier, which might reflect an effect of reaction time over predation risk. Nocturnal activity peaks shifted in time as the season progressed, indicating behavioural adjustments to sunrise hours. Moon phase did not affect attendance and activity levels of breeders in either habitat or overall aerial activity, but influenced arrival time at the colony during chick-rearing, individuals arriving later in periods of full moon. Skua capture rates were positively correlated with aerial and nest activity but not with overall breeder attendance and were unaffected by moon phase. Thin-billed prions activity budgets are influenced by environmental parameters that affect their likelihood of being predated.     

Development and validation of a new in vitro assay for selection of probiotic bacteria that express immune-stimulating properties in chickens in vivo

Oral administration of immunoprobiotic bacteria may support animal health. Species specificity of such microorganisms requires appropriate selection. An in vitro assay for the selection of immunoprobiotic lactic acid bacteria was developed in chicken. The assay allowed testing of large numbers of individual strains. Immune stimulation in vitro correlated well with the in vivo situation in two experiments and no false negative results occurred. Therefore this assay is an appropriate selection tool for immunomodulating properties of lactic acid bacteria in chicken.