Sleep and resting‐state functional magnetic resonance imaging connectivity in middle‐aged adults and the elderly: A population‐based study

Sleep problems increase with ageing. Increasing evidence suggests that sleep problems are not only a consequence of age‐related processes, but may independently contribute to developing vascular or neurodegenerative brain disease. Yet, it remains unclear what mechanisms underlie the impact sleep problems may have on brain health in the general middle‐aged and elderly population. Here, we studied sleep's relation to brain functioning in 621 participants (median age 62 years, 55% women) from the population‐based Rotterdam Study. We investigated cross‐sectional associations of polysomnographic and subjectively measured aspects of sleep with intrinsic neural activity measured with resting‐state functional magnetic resonance imaging on a different day. We investigated both functional connectivity between regions and brain activity (blood‐oxygen‐level‐dependent signal amplitude) within regions, hierarchically towards smaller topographical levels. We found that longer polysomnographic total sleep time is associated with lower blood‐oxygen‐level‐dependent signal amplitude in (pre)frontal regions. No objective or subjective sleep parameters were associated with functional connectivity between or within resting‐state networks. The findings may indicate a pathway through which sleep, in a ‘real‐life’ population setting, impacts brain activity or regional brain activity determines total sleep time.     

Reaktive Sauerstoffspezies und Gefäßdegeneration

Zeitschrift für Herz-,Thorax- und Gefäßchirurgie - Reaktive Sauerstoffspezies (ROS) erlangen in der derzeitigen Diskussion um die Genese der kardiovaskulären Degeneration eine...     

Acute effects and long-term outcome of pulmonary vein isolation in combination with electrogram-guided substrate ablation for persistent atrial fibrillation

Complex fractionated atrial electrographic (CFAE) catheter ablation is a new approach for the treatment of atrial fibrillation (AF). It is unclear if acute results of this approach correspond to long-term outcome. The purpose of this study was to prospectively assess acute and long-term successes of an ablation approach combining pulmonary vein isolation (PVI) and ablation of CFAE areas for treatment of persistent AF. PVI and ablation of CFAE areas were performed in 35 patients with persistent AF (30 men, 57+/-9 years of age). At the end of the ablation procedure AF had terminated in 23 of 35 patients (66%) by conversion to sinus rhythm (8 of 23 patients, 35%) or organization to atrial tachycardia (15 of 23 patients, 65%). AF persisted in 12 of 35 patients (34%). At the end of the follow-up period (19+/-12 months), sinus rhythm was present in 26 of 35 patients (74%), including 9 patients with a repeat procedure. This group of 26 patients consisted of 7 of 8 patients (88%) with acute sinus rhythm after the first ablation, 11 of 15 patients (73%) with organization, and 8 of 12 patients (66%) with ongoing AF (p=0.32). In conclusion, a combined approach of PVI and CFAE ablation in persistent AF leads to acute AF termination in 66% and long-term maintenance of sinus rhythm in 74% of cases. However, long-term outcome was not predictable by acute results of the ablation procedure.     

The influence of the ACE (<Emphasis Type="Italic">I/D</Emphasis>) polymorphism on systemic and renal vascular responses to angiotensins in normotensive,normoalbuminuric Type 1 diabetes mellitus

Aim/hypothesis The renin-angiotensin-aldosterone system is important in diabetic nephropathy, with the angiotensin-converting-enzyme DD-genotype being a renal risk factor. The D-allele is associated with higher ACE concentrations, but functional consequences in diabetes mellitus are not known. To analyse these consequences, we assessed renal and systemic responsiveness to angiotensin I infusion, with the response to angiotensin II as reference.Methods Uncomplicated Type 1 (insulin-dependent) diabetic patients with contrasting genotypes (11 II and 11 DD) were studied, during low (50 mmol/24 h) and liberal (200 mmol/24 h) sodium diet, during a euglycaemic clamp. Angiotensin I was infused at 4 and 8 ng·kg^–1·min^–1, 1 h each, followed by infusions of angiotensin II after a 2-h wash-out period.Results During low sodium, DD-homozygotes showed higher blood pressure sensitivity to angiotensin I (DD 21±5% vs II 15±5%, p<0.01). With liberal sodium, no differences in blood pressure were detected, whereas angiotensin I induced a higher response of ERPF (DD 40±5% vs II 35±4%, p<0.05) and RVR (DD 105±20% and II 89±16% p<0.05) in DD-homozygotes. Differences were not explained by altered angiotensin II sensitivity. Multiple-linear regression analysis showed that angiotensin I induced responses of blood pressure and renal haemodynamics are higher in subjects carrying the DD-genotype. The magnitude of the responses was modulated by sodium intake and long-term glycaemic control.Conclusion/interpretation This study showed that responses of blood pressure and renal haemodynamics to angiotensin I are increased in diabetic subjects carrying the DD-genotype. Genotype-associated differences in ACE concentrations could, under certain circumstances, have functional consequenses in uncomplicated Type 1 diabetes mellitus.Abbreviations RAAS Renin-angiotensin-aldosterone system - ERPF effective renal plasma flow - GFR glomerular filtration rate - RVR renal vascular resistance - FF filtration fraction - MAP mean arterial pressure - PRA plasma renin activity - Ang Angiotensin     

Correction to: Comparison of the 1-year clinical outcome of a novel cryoballoon to an established cryoballoon technology

Journal of Interventional Cardiac Electrophysiology -