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Third Test (third + test)

Distribution by Scientific Domains

Medical Sciences	100%

Selected Abstracts

The Complexity of External Acoustic Detection of Defects in Björk-Shiley Convexoconcave Heart Valves

ARTIFICIAL ORGANS, Issue 1 2001
Bas A. De Mol
Abstract: Fractures in Björk-Shiley convexoconcave (BScc) heart valves have raised questions about the feasibility of early diagnosis of technical defects by means of acoustic assessment. Three laboratory tests were conducted. To establish acoustic fingerprints, 66 valves with a defect, such as single-leg fracture (SLF) or single-leg separation (SLS), or without a defect were connected with a contact sensor and excited by dropping a small metal ball onto the outlet strut. In the second test, we simulated the valve sound propagation within the thorax. In the third test, intact, SLF, and SLS valves were placed in a mock heart immersed in a large water tank. We observed a resonance frequency corresponding with valve size and presence of defects. The second test showed that both the chest wall and the lungs created numerous reflections. This led to a substantial overlap of the original pulse frequencies and the frequencies measured. The third test confirmed that submersion of the chest in water can significantly reduce chest wall reflections. Reliable noninvasive assessment of BScc valve clicks for the presence of defects of the outlet strut is hampered by complex sound propagation within the thorax and variability of valve excitation. Acoustic fingerprints to diagnose mechanical defects should be integrated in valve design. [source]

Effects of desmopressin (DDAVP) on memory impairment following electroconvulsive therapy (ECT)

ACTA NEUROPSYCHIATRICA, Issue 3 2004
Ebrahim Abdollahian
Background:, Memory impairment is a common adverse effect of electroconvulsive therapy (ECT). Studies on animals and humans suggest that vasopressin improves the cognitive function, and positive effects of desmopressin on memory and learning have been reported. This research was performed for evaluation of the effects of desmopressin in the prevention of memory impairment following ECT. Methods:, This randomized, double-blind controlled clinical trial with placebo administration was performed on 50 patients with psychiatric disorders who were candidates for ECT. Subjects in the case group received 60 µm of intranasal desmopressin daily (in three doses of 20 µm). For the control group 0.9% saline solution was administered in the same way. Memory function was evaluated using Wechsler's Memory Scale three times a week (the first time before the start of ECT and the second and third times after the third and sixth sessions, respectively). Results were analyzed by t -test and Paired t -test. Results:, The mean age of patients was 29 years (range 20,40). During the course of ECT, patients in the control group demonstrated a meaningful decrease in memory scores (from a base score of 80.15,75.45 in the second test and 72.60 in the third test). Despite this, a meaningful increase in memory scores was observed during the treatment with desmopressin in the case group (from a base score of 73.27,75.70 and 79.13 in the second and the third tests, respectively). There was a meaningful difference between the two groups (P < 0.0001). Conclusion:, This study confirms the protective effect of desmopressin against memory impairment. The results confirm that memory impairment is a common side-effect of ECT and suggest that desmopressin may prevent ECT-induced memory impairment by its effects on memory and the learning process. [source]

Effect of quinapril on the attenuated heart rate recovery of type 2 diabetic subjects without known coronary artery disease

CLINICAL CARDIOLOGY, Issue 8 2004
Ilke Sipahi M.D.
Abstract Background: Heart rate (HR) recovery at 1 minis a measure of the vagal reactivation that occurs after cessation of exercise. Despite ample evidence about the association of attenuated HR recovery with increased mortality, pharmacologic modification of this predictor has not been shown. On the other hand, angiotensin-converting enzyme (ACE) inhibitors are known to have vagomimetic activity. Hypothesis: We hypothesized that ACE inhibition would increase HR recovery in a group of subjects known to have reduced HR recovery, namely diabetics. Methods: Maximal treadmill exercise stress test was performed in 31 type 2 diabetic and 31 nondiabetic male subjects with similar age, body mass index, and hypertensive status. None of the subjects had known heart disease or evidence of myocardial ischemia during the test. The diabetic subjects, after 2 weeks of treatment with quinapril, underwent a second exercise test. A third test was performed 2 to 3 weeks after cessation of quinapril treatment. Results: At baseline, despite similar exercise capacity, the diabetics had a lower HR recovery at 1 min than nondiabetics (25 ± 8 vs. 31 ± 8 beats/min, p<0.01). Quinapril significantly increased HR recovery at 1 min in diabetics (25 ± 8 beats/min at baseline vs. 28 ± 8 beats/min with quinapril vs. 25 ± 7 beats/min off-therapy, p < 0.01 by analysis of variance). Conclusions: The attenuated HR recovery of type 2 diabetics can be improved by quinapril. Whether the improvement in HR recovery with ACE inhibition can lead to decreased mortality is currently unknown. [source]