Dose-dependent blockade of the angiotensin II type 1 receptor with losartan in normal volunteers

Losartan, an angiotensin II type 1 receptor (AT1) antagonist, was developed as a more specific alternative to angiotensin-converting enzyme (ACE) inhibitors. At a daily dose of 50 mg, losartan is currently evaluated in large outcome trials involving patients with hypertension and postmyocardial infarction. The current study evaluated the level and duration of blockade of a pressor response to angiotensin II by 50 and 150 mg of losartan, compared with 32 mg of candesartan. Eight normotensive volunteers were randomly assigned to a single dose of losartan 50 or 150 mg, candesartan 32 mg, or placebo. Subjects were re-randomized after a 2-week washout period to complete all four study arms. Radial artery systolic pressure response to exogenous angiotensin II was measured at 2, 6, 12, and 24 h after administration of drug. Losartan 50 mg reduced the pressure response to exogenous angiotensin II significantly only at 6 h. In contrast, candesartan and losartan 150 mg produced a greater reduction in the pressure response to angiotensin II throughout the 24-h period. This suppression was not paralleled by a reduction in resting systemic arterial pressure. Higher doses than 50 mg of losartan might be evaluated to elicit optimal clinical effects.     

Chordal cutting VIA aortotomy in ischemic mitral regurgitation: surgical and echocardiographic study

BACKGROUND: Chordal cutting through atriotomy has been proposed to treat significant resting ischemic mitral regurgitation (MR) due to anterior leaflet tenting. In addition, MR may exacerbate during exercise not only trough exercise-induced ischemia but also through an increase in tenting area. Accordingly, we aimed to perform chordal cutting through aortotomy in patients with exercise-induced ischemic worsening of MR. METHODS: Five patients with ischemic MR, due to anterior leaflet tenting, which worsened during exercise echocardiography were enrolled. All patients underwent cutting of the 2 basal chordae attached to the anterior mitral leaflet associated with myocardial revascularization. Three patients had additional mitral valve annuloplasty. Postoperative MR was evaluated using exercise echocardiography. RESULTS: Age ranged from 63 to 78 years and 4 patients were male. Preoperative LV ejection fraction averaged 39 +/- 3%. Chordal cutting was performed through aortotomy allowing comfortable access to the anterior mitral valve. Mitral effective regurgitant orifice at rest and at peak exercise was reduced by surgery (10 +/- 3 to 0.6 +/- 0.5 mm(2) at rest and from 20 +/- 3 to 6 +/- 2 mm(2) at peak exercise; p = 0.03). Mitral tenting area at rest and at peak exercise was concomitantly reduced by surgery (1.83 +/- 0.21 cm(2) to 0.50 +/- 0.4 cm(2) at rest and from 3.11 +/- 0.58 to 1.7 +/- 0.5 cm(2) at peak exercise; p = 0.03). Left ventricular size and function remained unchanged after surgery. CONCLUSIONS: Chordal cutting through aortotomy may be an effective option to treat ischemic MR due to anterior leaflet tenting. Associated with myocardial revascularization, it resulted in a decrease of MR at rest and during exercise through a decrease in tenting area without impairment of LV function.     

Respiratory viral infection in lower airways of asymptomatic children

Aim: The aim of this study was to determine if asthmatic children have viruses more commonly detected in lower airways during asymptomatic periods than normal children. Methods: Fifty‐five asymptomatic children attending elective surgical procedures (14 with stable asthma, 41 normal controls) underwent non‐bronchoscopic bronchoalveolar lavage. Differential cell count and PCR for 13 common viruses were performed. Results: Nineteen (35%) children were positive for at least one virus, with adenovirus being most common. No differences in the proportion of viruses detected were seen between asthmatic and normal ‘control’ children. Viruses other than adenovirus were associated with higher neutrophil counts, suggesting that they caused an inflammatory response in both asthmatics and controls (median BAL neutrophil count, 6.9% for virus detected vs. 1.5% for virus not detected, p = 0.03). Conclusions: Over one‐third of asymptomatic children have a detectable virus (most commonly adenovirus) in the lower airway; however, this was not more common in asthmatics. Viruses other than adenovirus were associated with elevated neutrophils suggesting that viral infection can be present during relatively asymptomatic periods in asthmatic children.     

Septic pseudo-aneurysm of the left main trunk in a dialysis patient

This case report relating the association between a septic pseudo-aneurysmof the left trunk and myocardial infarction underscores theimportance of early non-invasive imaging when acute myocardialinfarction is associated with frank clinical or biological signsof systemic sepsis.     

Exercise Training in Chronic Heart Failure: Why?

Rest has long been considered mandatory in the treatment of chronic heart failure. In recent years, emphasis has been given to two emerging hallmarks of the syndrome: the abnormalities of the peripheral circulation and those of the peripheral muscles. Recent experimental and clinical studies have shown that training has the potential to reverse these abnormalities and improve patients' functional status. This article reviews these observations.     

Accelerated immune red cell destruction in the absence of serologically detectable alloantibodies

Two patients are described in whom clinically significant red blood cell alloantibodies could be demonstrated only by in vivo 51chromium (51Cr) survival studies. The first patient had experienced a severe delayed hemolytic transfusion reaction to four units of crossmatch compatible blood. Serial phenotype studies suggested the presence of a serologically undetectable anti-c (hr') antibody. 51Cr survival of c- positive red blood cells was one per cent at 24 hours, while survival of c-negative red blood cells was 80 per cent at 24 hours. The second patient had multiple red blood cell alloantibodies. An anti-c antibody was suspected but could not be convincingly demonstrated by in vitro techniques. 51Cr survival of c-positive red blood cells, however, was 57 per cent at 24 hours and 17 per cent at 48 hours. 51Chromium red blood cell survival studies should be considered whenever an unexplained hemolytic transfusion reaction occurs, or when an expected red blood cell alloantibody cannot be demonstrated by in vitro laboratory studies.     

Mid-ventricular ballooning heart syndrome

Stress cardiomyopathies have been increasingly reported these last years, especially in women as a transient left ventricular apical ballooning syndrome. We report six cases in whom, in the context of anxious situations, echocardiograms and ventriculographies revealed mid-ventricular akinesis with preservation of apical and basal contractilities with normal coronary arteriography. This "mid-ventricular ballooning heart syndrome " should probably be classified as a new type of heart stress related syndrome.