Effects of saralasin on arterial compliance in normotensive and hypertensive rats. Role of endothelium.

We used an experimental model of in situ isolated carotid arteries to clarify the participation of angiotensin II (Ang II) in the mechanical properties of the arterial wall in 12-week-old Wistar-Kyoto (WKY) and spontaneously hypertensive rats (SHRs). The effects of local incubation with saralasin ([Sar1,Thr8]Ang II, 10(-6) M) on carotid compliance were compared with the effects of endothelium removal and with those of total abolition of vasomotor tone with potassium cyanide (0.1 mg/ml). Operating carotid compliance measured for pressure values close to the mean arterial pressure of each group was (mean +/- SD) 12.6 +/- 2.9 x 10(-3) microliters/mm Hg.mm vessel in WKY rats and 8.2 +/- 1.6 x 10(-3) microliters/mm Hg.mm vessel in SHRs (p less than 0.001). With intact endothelium, local incubation with saralasin increased carotid compliance by 24% in WKY rats and 23% in SHRs relative to control values (p less than 0.05 and p less than 0.001, respectively). Endothelium removal induced significant increases in carotid compliance in WKY rats (17%, p less than 0.01) and in SHRs (33%, p less than 0.001). After endothelium removal, saralasin induced significant further carotid compliance increases in both strains (+18%, p less than 0.001, and +11%, p less than 0.01, in WKY rats and SHRs, respectively). After potassium cyanide poisoning, carotid compliance did not increase further relative to saralasin values in both strains with or without endothelium. These findings suggest that Ang II receptors play a major role in the control of the basal vasomotor tone of large arteries in both normotensive and hypertensive rats.(ABSTRACT TRUNCATED AT 250 WORDS)

Vascular endothelium, mechanical properties of the arterial wall and local angiotensin converting enzyme inhibition.

METHODS: An experimental model of in situ isolated carotid arteries was used to study the contribution made by angiotensin II (Ang II) towards the mechanical properties of the arterial wall in 12-week-old Wistar-Kyoto (WKY) and spontaneously hypertensive (SHR) rats. The effects of local incubation with saralasin (Sar1-Thr8-Ang II, 10(-6) mol/l) and with lisinopril (5 x 10(-6) mol/l) on carotid compliance were compared to the effects of removing the endothelium and the effects of totally abolishing vasomotor tone with potassium cyanide (0.1 mg/ml). RESULTS: With an intact endothelium, local incubation with lisinopril increased carotid compliance by 23% in WKY rats (P less than 0.05) and by 14% in SHR (P less than 0.01). Under the same experimental conditions, saralasin increased carotid compliance by 24% in WKY rats and 23% in SHR relative to control values (P less than 0.05 and P less than 0.001, respectively). Removal of the endothelium induced significant increases in carotid compliance in WKY rats (17%, P less than 0.01) and in SHR (33%, P less than 0.001). After removal of the endothelium, there was no further increase in carotid compliance with lisinopril in either strain. In contrast, saralasin induced further significant compliance increases in both strains (+18%, P less than 0.001, and +11%, P less than 0.01, in WKY and SHR, respectively). After the artery had been poisoned with potassium cyanide, there was no further increase in compliance relative to values obtained with saralasin in either strain with or without the endothelium. CONCLUSIONS: These findings suggest that Ang II receptors have a major effect on the control of basal vasomotor tone of large arteries in both normotensive and hypertensive rats. Furthermore, the increase in carotid compliance induced by local incubation with saralasin and with angiotensin converting enzyme (ACE) inhibitors may involve similar mechanisms acting on smooth muscle angiotensin receptors.

[Usefulness of transesophageal echocardiography to optimize treatment after ischemic stroke]. / Intérêt de l'échocardiographie trans-œsophagienne dans l'optimisation de la stratégie thérapeutique après un accident vasculaire cérébral ischémique.

AIM OF THE STUDY: In the setting of ischemic stroke, the place of transesophageal echocardiography (TEE) is still matter of debate. The aim of the study is to evaluate the therapeutic impact provided by TEE and to characterize patients in whom TEE is warranted. PATIENTS AND METHOD: Three hundred and fifty-nine consecutive patients were included in the study. "Decisive TEE" (DTEE) was defined by echographic findings resulting in a change of treatment, whereas "informative TEE" (ITEE) was defined by TEE revealing a potential cardiac or aortic source of embolism. RESULTS: Three hundred and forty-one patients underwent TEE. Twenty-eight patients (8.2%) had DTEE and 184 (53.9%) had ITEE. DTEE were as follows: thrombus in the left atrial appendage in 6 patients, complex aortic plaques in 10 patients, patent foramen ovale (PFO) associated with atrial septal aneurism (ASA) and an important right to left shunt (3 patients), FOP associated with ASA and lower limb phlebitis (1 patient), 4 cases of endocarditis and 4 patients with intense spontaneous echo contrast in the left atrium. In most cases of DTEE (67.8%), the patient was given anticoagulation drugs. Left atrial dilatation (P=0.005) and multivessel territory stroke (P=0.018) were statistically predictive of DTEE. CONCLUSIONS: In the setting of ischemic stroke, TEE provides important additional informations, but modifies therapeutic strategy in less than 10% of cases. Multivessel territory stroke, and left atrial dilatation were predictive of DTEE.

[Secondary prevention after acute coronary syndrome: therapeutic goals achievement in relation with changes in guidelines]. / Prévention secondaire après syndrome coronarien aigu: évolution des recommandations et niveaux d'atteinte des objectifs.

BACKGROUND: Secondary prevention is a key strategy for reducing levels of coronary heart disease, but a gap between guidelines and practice remains. OBJECTIVES: The aim of this double-part survey was to evaluate the improvement in secondary prevention one year after acute coronary syndrome (ACS) in real life, between 1999 and 2005, with respect to the change in guidelines. METHODS: Two surveys of almost similar design were performed in 1999 and 2005-2006. In each survey, unselected consecutive patients suffering from ACS (n=112 hospitalized in 1998, and n=110 in 2004) were evaluated at admission, and one year after hospitalization, for the risk factors, lifestyle, and achievement of therapeutic goals recommended by the most recent guidelines. Follow-up (FU) data were obtained by mail and phone contact with patient, general practitioner and cardiologist, and medical laboratory when appropriate. RESULTS: At 1-year FU (n=192 survivors with FU), smoking cessation (87% in 1999 versus 89% in 2005) and obesity (13% versus 19%, respectively) did not vary significantly. Blood pressure was controlled (< 140/90 mmHg, excepted in diabetics in 2005 with less than 130/80 mmHg) in 65% versus 80% (p<0.03). The rate of patients with no or controlled diabetes mellitus decreased from 1999 to 2005 (90% versus 76%), despite more intensive treatment (insulin in 1% versus 20%).The goals for LDL cholesterol were achieved in 47% of patients in 1999 (< 3.4 mmol/L) and in 76% in 2005 (< 2.6 mmol/L) (p<0.0001). Goals for triglycerides were achieved in 86% in 1999 (< 2g/L), and in 80% in 2005 (< 1.5 g/L) (NS). Besides, 63% of patients received an hypolipemic drug in 1999 (a statin in 59%) and 91% in 2005 (a statin in 88%). Mean number of controlled risk factors was 3.96+/-1.52 in 1999 versus 4.94+/-1.83 in 2005, and prevalence of pts with more than five controlled risk factors at one year FU increased from 15 to 44% (p<0.0001). CONCLUSIONS: These results, drawn from unselected consecutive patients managed in real life, demonstrate an improvement in secondary prevention one year after ACS, between 1999 and 2005, despite strengthened guidelines for blood pressure, triglycerides and LDL cholesterol levels. Control of obesity and diabetes remains unoptimal.

Coronary to bronchial artery anastomosis with bronchial steal syndrome demonstrated by thallium-201 myocardial tomoscintigraphy.

A case study is presented in which the bronchial steal syndrome is demonstrated by stress thallium-201 myocardial perfusion imaging. The various aspects of the syndrome are discussed. We conclude that bronchial steal syndrome may provoke severe myocardial ischaemia even in the absence of coronary artery stenosis.