Search

Increased arterial stiffness (AS) has been described as a predictor of atrial fibrillation (AF). This study was performed to assess whether increased AS leads to a higher symptom burden in patients with AF.

A critical problem in cardiovascular MRI in small rodents is adjusting the sequence acquisition to the high heart and respiratory rates. The aim of this study was to compare a retrospectively self-gated fast low angle shot navigator (RSG-FLASH) sequence with a conventional prospectively triggered (PT-FLASH) sequence for cine imaging of the ascending aorta in mice at 9.4 T.

Chronic stress is associated with increased stroke risk. However, the underlying pathophysiological mechanisms are poorly understood. We examined the effects of chronic stress on endothelial function and ischemic brain injury in a mouse model.

Vascular effects of mental stress are only partially understood. Therefore, we studied effects of chronic stress and heart rate (HR) on endothelial function and cerebral ischemia.

Low-density lipoproteins (LDL) are atherogenic and represent a strong cardiovascular risk factor. Therefore, LDL-cholesterol (LDL-C) remains the primary target in lipid lowering therapy. However, since many cardiovascular events occur despite an optimal LDL-C, it is necessary to focus on the remaining cardiovascular risk. Treatment of low high-density lipoprotein-cholesterol (HDL-C) and high triglycerides (TG) are options to achieve cardiovascular risk reduction beyond LDL. HDL mediates reverse cholesterol transport and exerts several other athero-protective effects. Epidemiologic evidence has shown that low HDL-cholesterol (HDL-C) is a strong and independent cardiovascular risk marker. However, since the anti-atherogenic effects of HDL particles depend on their functionality rather than on their cholesterol content, an increase in HDL-C concentration does not always have to result in a clinical benefit. Besides established strategies to increase HDL-C, e.g. with fibrates and nicotinic acid, CETP (Cholesteryl ester transfer protein)-inhibition is a promising new therapeutic option. The failure of torcetrapib, the first CETP-inhibitor, seems to be attributed to “off-target” effects. Treatment with the newer CETP-inhibitors dalcetrapib and anacetrapib has been shown to be efficacious and safe - but their usefulness in clinical practice remains to be determined in ongoing clinical endpoint trials. TG concentrations have been shown to correlate with cardiovascular risk. However, interpretation of plasma TG concentrations remains difficult due to considerable intra-individual variability of plasma concentrations. Post-prandial triglyceride concentrations may be better predictors of cardiovascular risk than fasting TG. In patients with hypertriglyceridemia, achievement of the LDL-C goal remains the primary lipid target. The basis of therapy in patients with hypertriglyceridemia are life style modifications. In addition, non-HDL-C should be addressed. For selected patients, treatment with fibrates, nicotinic acid or omega-3 fatty acids are available to lower TG concentrations. In summary, the focus of lipid therapy is the reduction of cardiovascular risk rather than the modification of lipoprotein sub-fractions. Ongoing research points towards a shift of the focus from the HDL-C concentrations to parameters of HDL function and from fasting TG to TG kinetics.

Angiotensin receptor blockers enhance endothelial function and are suggested to improve erectile function. The effects and underlying mechanisms of treatment with the angiotensin receptor blocker irbesartan on penile endothelial function in apolipoprotein E (ApoE)(-/-) mice were determined. Wild-type (C57/B6) and ApoE(-/-) mice were fed with a high-fat, cholesterol-rich diet for 7 weeks and treated with irbesartan (50 mg/kg . day) or hydralazine (250 mg/l). Vital parameters were measured with the tail-cuff method. Endothelial (aortic rings) and erectile function (corpora cavernosa) were assessed by pharmacological stimulation in an organ bath chamber. Oxidative stress and angiotensin receptor expression were determined. Blood pressure was significantly decreased in irbesartan- and hydralazine-treated ApoE(-/-) mice (p < 0.05) compared with controls and wild-type mice. Endothelial function of the aorta and corpus cavernosum was significantly impaired in ApoE(-/-) mice (p < 0.05) and could be restored by treatment with irbesartan (p < 0.05). Consistently, nitric oxide production of corpora cavernosa was impaired in ApoE(-/-) mice (p < 0.01), with a restoration in irbesartan- but not hydralazine-treated mice. Dihydroethidium-stained sections and lipid peroxidase assay revealed a reduction of superoxide production in irbesartan (p < 0.05) compared with hydralazine-treated and control ApoE(-/-) mice. In summary, irbesartan improves penile endothelial function in ApoE(-/-) mice by reduction of vascular and cavernosal oxidative stress. This result emphasizes the beneficial effect of inhibition of the renin-angiotensin system even in terms of erectile function.