Long-Term Course of Circulating Elastin, Collagen Type I, and Collagen Type III in Patients with Spontaneous Cervical Artery Dissection: a Prospective Multicenter Study.

An impaired integrity of vascular elements and the extracellular matrix (ECM) has been discussed to play a critical role in the pathophysiology of spontaneous cervical artery dissection (sCAD). This study aimed to explore the temporal course of circulating elastin, collagen type I, and collagen type III in patients with sCAD and evaluated their eligibility as diagnostic biomarkers. Patients with sCAD were prospectively enrolled in four German stroke centers. Blood samples were collected at baseline (acute phase), at day 10 ± 3 (subacute phase), and after 6 ± 1 months (chronic phase). Patients with acute ischemic stroke not related to sCAD, healthy probands, and patients undergoing thromboendarterectomy of the carotid artery served as control groups. Serum levels of elastin and collagen types I and III were determined by ELISAs. Fifty-seven patients with sCAD were enrolled. Compared to all three control groups, patients with sCAD had significantly lower levels of elastin and collagen type III at baseline and after 6 months. Compared to healthy probands, patients with sCAD showed similar collagen type I levels at baseline and in the subacute phase, but significantly increased levels after 6 months. As serum levels of elastin, collagen types I and III were not elevated in the acute phase, they do not appear eligible as biomarkers for the diagnosis of sCAD. Persisting low serum levels of elastin and collagen type III towards the chronic phase of sCAD strengthens the hypothesis of a subtle, in most cases clinically inapparent affection of the ECM in patients with sCAD.

Diverse autonomic regulation of pupillary function and the cardiovascular system during alcohol withdrawal.

BACKGROUND: Previous research indicated the complexity of autonomic dysfunction during acute alcohol withdrawal. This study aimed to investigate the pupillary light reflex as an indicator of midbrain and brainstem regulatory systems in relation to cardiovascular autonomic function. METHODS: Thirty male patients were included in the study. They were investigated during acute alcohol withdrawal syndrome and 24h later during clomethiazole treatment and compared to healthy controls. Parameters of pupillary light reflex of both eyes as well as heart rate variability, blood pressure variability and baroreflex sensitivity (BRS) were studied. RESULTS: We observed significantly reduced sympathetic (small diameter, e.g., left eye: 5.00 in patients vs. 5.91 mm in controls) and vagal modulation (e.g., prolonged latencies, left eye: 0.28 vs. 0.26 ms) regarding both pupils during acute alcohol withdrawal syndrome. Cardiovascular parameters showed reduced vagal modulation (e.g., b-slope of BRS: 7. 57 vs. 13.59 ms/mm Hg) and mixed results for sympathetic influence. After 24h, autonomic dysfunction improved significantly, both for the pupils (e.g., left diameter: 5.38 mm) and the heart (e.g., b-slope of BRS: 9.34 ms/mm Hg). While parameters obtained from the pupil correlated with cardiac autonomic function (e.g, BRS and left diameter: r=0.564) in healthy controls, no such pattern was observed in patients. CONCLUSION: Results obtained from the pupil during acute alcohol withdrawal do not simply mirror autonomic dysfunction regarding the heart. Pupillary and cardiovascular changes after 24h indicate state dependencies of the results. The findings are discussed with respect to autonomic mechanisms and potentially involved brain regions.

Endothelial dysfunction during acute alcohol withdrawal syndrome.

BACKGROUND: Endothelial dysfunction (EF) is a central phenomenon in a variety of conditions associated with increased cardiovascular morbidity. Here, we investigated EF during acute alcohol withdrawal syndrome before and 24h after medication. We aimed to analyze microcirculation, applying the post-occlusive reactive hyperemia (PORH) test and spectral analysis of skin vasomotion as markers of EF. Additionally, we explored whether segmentation of spectral analysis data may disclose more detailed information on dynamic blood flow behavior. METHODS: We investigated 30 unmedicated patients during acute alcohol withdrawal syndrome and matched controls. Patients were reinvestigated after 24h when half of them had been treated with clomethiazole. Capillary blood flow was assessed on the right forearm after compression of the brachial artery. Parameters of PORH such as time to peak (TP), slope and PORH indices were calculated. Spectral analysis was performed in order to study five different frequency bands. Withdrawal symptoms were quantified by means of the alcohol withdrawal scale (AW scale). RESULTS: We observed a blunted hyperemic response in patients after occlusion of the brachial artery indicated by significantly increased TP and decreased PORH indices. In contrast, vasomotion as investigated by spectral analysis was not altered. Segmentation analysis revealed some alterations in the cardiac band at rest, and indicated differences between treated and untreated patients after 24h. CONCLUSION: Our results suggest peripheral endothelial dysfunction in patients during acute alcohol withdrawal. No major influence of treatment was observed. Future studies need to address the relation of EF to cardiac morbidity during alcohol withdrawal.