Search results for " vasospasm"

Impairment of the extrusion transporter for asymmetric dimethyl-L-arginine: a novel mechanism underlying vasospastic angina.

2012

Abstract A 37-year old male patient presented with frequent angina attacks (up to 40/day) largely resistant to classical vasodilator therapy. The patient showed severe coronary and peripheral endothelial dysfunction, increased platelet aggregation and increased platelet-derived superoxide production. The endothelial nitric oxide synthase (eNOS)-inhibitor N G -nitro- l -arginine methyl ester (L-NAME) reduced superoxide formation in platelets identifying “uncoupled” eNOS as a superoxide source. Oral l -arginine normalized coronary and peripheral endothelial dysfunction and reduced platelet aggregation and eNOS-derived superoxide production. Plasma concentrations of the endogenous NOS inhibito…

Comparison of the anticonstrictor action of dihydropyridines (nimodipine and nicardipine) and Mg2+ in isolated human cerebral arteries.

1992

The isometric tension recorded from ring segments of branches of human middle cerebral artery was the parameter used to study the inhibition of spasmogen-induced contractions as model for cerebral vasospasm. Concentration-response curves to 5-hydroxytryptamine (10(-9)-3 x 10(-5) M) and prostaglandin F2 alpha (10(-7)-3 x 10(-5) M) were inhibited in Ca(2+)-free medium and in Ca(2+)-free medium to which EGTA (1 mM) had been added, respectively. Nimodipine (10(-7), 10(-5) M), nicardipine (10(-7), 10(-5) M) and Mg2+ (magnesium sulfate 10(-4), 10(-2) M) inhibited the 5-HT-elicited contractions, and this inhibition was similar for the highest concentrations tested. In contrast, nimodipine and nica…

Effect of intraarterial papaverine or nimodipine on vessel diameter in patients with cerebral vasospasm after subarachnoid hemorrhage.

2012

Papaverine (P) and nimodipine (N) are the most widely used vasodilators when angiographic and symptomatic vasospasm is present after subarachnoid aneurysmatic hemorrhage (SAH). Their effect is only short-lived and no direct comparisons have been undertaken to evaluate the action of both substances directly. We retrospectively assessed the effect of either P or N on angiographic diameter reduction and capillary blood flow.Fifteen SAH patients with secured aneurysms and cerebral vasospasm received intraarterial P, fifteen similar patients received N. As the primary endpoint, pre- and post-infusion arterial diameters and capillary blood flow were rated retrospectively on angiographies and comp…

Transcranial Doppler diagnosis of cerebral vasospasm following subarachnoid haemorrhage: correlation and analysis of results in relation to the age o…

1994

A retrospective analysis was undertaken to determine whether cerebral vasospasm following subarachnoid haemorrhage (SAH) correlates with the age of patients. For at least 3 weeks after bleeding 80 subjects underwent very close follow-up with clinical examination and transcranial Doppler records of the blood velocities within the basal cerebral arteries. Firstly a correlation between measured maximal mean blood flow velocities and age was made. Secondly, according to their age and the maximum of recorded mean velocities (v), the patients were divided into groups as follows: age 55 years or less, age more than 55 years; and maximum velocity v190 cm/s, 90 cm/sv2120 cm/s, 120 cm/sv3160 cm/s, v4…

A rare case of Prinzmetal angina 3 days after coronary artery stenting with a second-generation drug-eluting stent

2015

Non previsto.

Endothelin: an endothelium-derived vasoactive peptide and its possible role in the pathogenesis of cerebral vasospasm

1991

The contractile response to endothelin has been examined in cerebral arteries from rats subjected to a prior subarachnoid haemorrhage (SAH) and compared with saline injected controls. Endothelin elicited strong concentration-dependent contraction of rat basilar artery segments. The response was slow in onset and long lasting. The endothelin-induced contraction was much stronger in the SAH compared to control animals. Our findings suggest a role of the peptide in the pathophysiology of cerebral vasospasm.

Incidenza del vasospasmo e correlazione tra la neuroradiologia per immagini e l’emodinamica cerebrale

2008

[Ischemia with no obstructive coronary artery disease: microvascular angina and vasospastic angina].

2020

About 40% of patients undergoing coronary angiography for chest pain with anginal features have angiographically normal or near-normal coronary arteries. It was necessary to standardize all myocardial ischemia scenarios in stable patients in the absence of coronary artery disease, therefore the term INOCA (ischemia with non-obstructive coronary artery disease) was coined. The aim of this article is to summarize and to clarify the vast and controversial chapter of INOCA, in order to better understand the pathophysiological, nosographic, diagnostic and therapeutic aspects.

A Volumetric Method for Quantification of Cerebral Vasospasm in a Murine Model of Subarachnoid Hemorrhage

2018

Subarachnoid hemorrhage (SAH) is a subtype of hemorrhagic stroke. Cerebral vasospasm that occurs in the aftermath of the bleeding is an important factor determining patient outcome and is therefore frequently taken as a study endpoint. However, in small animal studies on SAH, quantification of cerebral vasospasm is a major challenge. Here, an ex vivo method is presented that allows quantification of volumes of entire vessel segments, which can be used as an objective measure to quantify cerebral vasospasm. In a first step, endovascular casting of the cerebral vasculature is performed using a radiopaque casting agent. Then, cross-sectional imaging data are acquired by micro computed tomograp…

DOSE-RELATED EFFICACY OF A CONTINUOUS INTRACISTERNAL NIMODIPINE TREATMENT ON CEREBRAL VASOSPASM IN THE RAT DOUBLE SUBARACHNOID HEMORRHAGE MODEL

2009

Objective Intracisternal continuous therapy is a concept in the treatment of cerebral vasospasm after subarachnoid hemorrhage. The purpose of the current study was to investigate the effect of intracisternal nimodipine after induced vasospasm. Methods Sixty-five male Wistar rats were randomized into 4 groups: the control sham-operated group, the control subarachnoid hemorrhage-only group, and the treatment groups receiving 5 or 10 microL/hour of intracisternal nimodipine continuously for 5 days via subcutaneously implanted Alzet osmotic pumps (Durect Corp., Cupertino, CA). Vasospasm was analyzed 5 days later by means of digital subtraction angiography. Morphological examination of the brain…