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D Salem

Publications and source records attributed to D Salem.

10 recordsLinked to original sources

Effect of enalapril on myocardial infarction and unstable angina in patients with low ejection fractions.

An association between raised renin levels and myocardial infarction has been reported. We studied the effects of enalapril, an angiotensin-converting enzyme (ACE) inhibitor, on the development of myocardial infarction and unstable angina in 6797 patients with ejection fractions < or = 0.35 enrolled into the two Studies of Left Ventricular Dysfunction (SOLVD) trials. Patients were randomly assigned to placebo (n = 3401) or enalapril (n = 3396) at doses of 2.5-20 mg per day in two concurrent double-blind trials with the same protocol. Patients with heart failure entered the treatment trial (n = 2569) and those without heart failure entered the prevention trial (n = 4228). Follow-up averaged 40 months. In each trial there were significant reductions in the number of patients developing myocardial infarction (treatment trial: 158 placebo vs 127 enalapril, p < 0.02; prevention trial: 204 vs 161 p < 0.01) or unstable angina (240 vs 187 p < 0.001; 355 vs 312, p < 0.05). Combined, there were 362 placebo group patients with myocardial infarction compared with 288 in the enalapril group (risk reduction 23%, 95% CI 11-34%; p < 0.001). 595 placebo group patients developed unstable angina compared with 499 in the enalapril group (risk reduction 20%, 95% CI 9-29%, p < 0.001). There was also a reduction in cardiac deaths (711 placebo, 615 enalapril; p < 0.003), so that the reduction in the combined endpoint of deaths, myocardial infarction, and unstable angina was highly significant (20% risk reduction, 95% CI 14-26%; p < 0.0001). Enalapril treatment significantly reduced myocardial infarction, unstable angina, and cardiac mortality in patients with low ejection fractions.

Angina, Unstable

Syncope: current diagnostic evaluation and management.

OBJECTIVE: To provide a comprehensive review of the causes, current diagnostic evaluation, and treatment of syncope. DATA IDENTIFICATION: New data and knowledge in this evolving field were critically analyzed by doing a MEDLINE search on syncope supplemented by selective review of English language literature citations in the Index Medicus before 1980. STUDY SELECTION: We reviewed approximately 200 published articles on syncope and closely related topics as well as using our own clinical experience. We selected articles if they addressed the pathophysiology of syncope, classification and causes, differential diagnosis, noninvasive and invasive evaluation, and current therapy. RESULTS OF DATA SYNTHESIS: Syncope is a common clinical problem, occurring in 30% to 50% of the adult population. The prognosis for syncope depends on its cause. Cardiac syncope has the worst prognosis and therefore mandates thorough evaluation and prompt treatment. Diagnostic evaluation is made difficult by the transient nature of the episodes and the many causes. Noninvasive testing reveals the cause of syncope in approximately 50% of cases. More extensive evaluation, including invasive electrophysiologic studies, has assumed a larger role in defining the cause of syncope in selected patients with structural heart disease in whom a noninvasive evaluation has been nondiagnostic. Recently tilt-table studies have been proposed as a clinically useful noninvasive test for vagally mediated syncope. CONCLUSIONS: A rational stepwise diagnostic and therapeutic approach to patients with syncope can be developed by initially doing a careful history and physical examination followed by a noninvasive evaluation and selective use of additional, more specialized or invasive tests. Future research should focus on defining the validity and utility of current diagnostic testing in syncope and on exploring further the pathophysiology of patients with recurrent, unexplained syncope.

Cardiovascular Diseases

Calcium homeostasis in untreated pulmonary tuberculosis. I--Basic study.

This study has been done to evaluate serum calcium, phosphorus (P), magnesium, parathyroid hormone (PTH), calcitonin (CT), and cyclic adenosine monophosphate (cAMP) in recently diagnosed pulmonary tuberculous patient, (n = 61) and the results were compared with the healthy control group (n = 22). Twenty four hours urine was collected for estimation of these electrolytes as well as cAMP. Nephrogenous cAMP (NcAMP) was calculated. Serum Ca and PTH were significantly reduced in TB groups, but CT was elevated. Serum Mg, P and cAMP as well as urinary Ca and Mg in TB groups were similar to that of the control group. Urinary P, cAMP NcAMP were increased in patient groups compared with the control. The reduced serum Ca could be due to impaired intestinal absorption of Ca, or deficient intake as a result of anorexia, decreased plasma albumin, decreased active metabolites of vitamin D or elevated CT. The rise in serum CT in TB might be due to increased CT secreted from the bronchial K-cells. Increased NcAMP might be due to the associated increase in serum antidiuretic hormone (ADH). The elevated urinary P in TB could be attributed to tissue breakdown, decreased serum PTH or increased CT.

Adult

External cardiac programmed stimulation for noninvasive termination of sustained supraventricular and ventricular tachycardia.

To examine the feasibility of using a noninvasive temporary pacemaker for termination of well-tolerated supraventricular (SVT) and ventricular tachycardia (VT), a standard external demand pacemaker was modified to allow stimulation with single or multiple extrastimuli and overdrive pacing. To evaluate the efficacy, safety and tolerance of external cardiac programmed stimulation, a standard arrhythmia termination protocol was used in 223 tachycardias in 22 patients. The technique of external cardiac programmed stimulation was used in 209 episodes of SVT in 13 patients. It terminated 95% of the episodes with success in 19 of 20 episodes of atrioventricular nodal reentrant tachycardia and 179 of 189 episodes of atrioventricular reciprocating tachycardia. Of 198 episodes of SVT terminated by the technique 168 (85%) were terminated by a single extrastimulus and 28 (14%) by double extrastimuli. Only 2 episodes of SVT required overdrive pacing for termination. External cardiac programmed stimulation did not result in atrial fibrillation or arrhythmia acceleration. Of 14 episodes of sustained monomorphic VT 5 were terminated by external cardiac programmed stimulation. One tachycardia was terminated by a single extrastimulus, 1 by double extrastimuli and 3 by overdrive pacing. Arrhythmia acceleration occurred once and was terminated by endocardial pacing. On 27 separate occasions patient evaluation of maximal discomfort included 4 ratings of mild, 10 of moderate, 11 of severe and 2 of intolerable discomfort. External cardiac programmed stimulation is effective and safe in patients with well-tolerated sustained supraventricular or ventricular arrhythmias.

Adult

Apolipoprotein A-I gene polymorphism associated with premature coronary artery disease and familial hypoalphalipoproteinemia.

Decreased plasma high-density-lipoprotein (HDL) cholesterol and apolipoprotein A-I levels have been associated with premature coronary artery disease. We identified a PstI restriction-endonuclease site flanking the human apolipoprotein A-I gene at its 3' end that is polymorphic. The absence and presence of this site, as determined by genomic blotting analysis of PstI-digested chromosomal DNA with the use of an apolipoprotein A-I gene probe, were associated with 3.3-kb and 2.2-kb hybridization bands, respectively. The 3.3-kb band appeared in 4.1 percent of 123 randomly selected control subjects and in 3.3 percent of 30 subjects with no angiographic evidence of coronary artery disease. In contrast, among 88 patients who had severe coronary disease before the age of 60, as documented by angiography, the 3.3-kb band occurred in 32 percent (P less than 0.0001). It was also found in 8 of 12 index cases (P less than 0.0001) of kindreds with familial hypoalphalipoproteinemia. In the two patient groups, the allele frequencies of the site that produced the 3.3-kb band were 17 and 42 percent, respectively, as compared with an allele frequency of only 2 percent in the control populations. Within kindreds with familial hypoalphalipoproteinemia and among first-degree relatives of patients with coronary artery disease, the 3.3-kb band was associated with decreased HDL cholesterol levels. Among all patients with coronary artery disease, 58 percent had HDL cholesterol levels below the 10th percentile of normal values; however, this frequency increased to 73 percent when patients with the 3.3-kb band were considered. These findings indicate that the polymorphism in the region between the apolipoprotein A-I and apolipoprotein C-III genes may be a useful marker for the risk of premature coronary artery disease and familial hypoalphalipoproteinemia.

Age Factors

Visual acuity screening of children 6 months to 3 years of age.

The operant preferential looking (OPL) procedure allows a behavioral estimate of visual acuity to be obtained from children 6 mo to 3 yr of age. In clinical settings, there is often too little time available to obtain an acuity estimate with the standard OPL procedure. The goal of this study was to identify specific spatial frequencies, termed diagnostic grating frequencies, that could enable the OPL technique to be used as a screening procedure under conditions where completion of acuity estimation was not possible. One hundred eighty presumptively normal children, 6, 12, 18, 24, 30, and 36 mo of age, were each tested with up to 20 trials of a potential diagnostic grating frequency to determine the highest spatial frequency grating that could be resolved by 90% of children at each age. For all ages except 18 mo, there existed a spatial frequency that produced uniformly high OPL performance within the age group; this spatial frequency was separated by one-half to one octave from a higher spatial frequency that more than 30% of children at that age failed to detect. These results suggest that at all ages except 18 mo, it should be possible to use the OPL procedure as a vision screening tool by testing individual children with the diagnostic grating frequency appropriate for their age.

Child, Preschool

SPECT resolution and uniformity improvements by noncircular orbit.

A noncircular orbit implemented by a combination of rotational and translational motions in single photon emission computed tomography improves significantly the image resolution and uniformity. The former is realized by closer access of the detector to the object at each projection angle, and the latter by suppression of ring artifacts through the shifts in the distance between the centers of detector and object. This has been demonstrated by comparing the SPECT images for an elliptical orbit of 40 cm X 30 cm with the equivalent circular orbit of 40 cm diameter, performed by SPECT system with a high resolution collimator. Resolution FWHM improvements were 1.5-2.5 mm. Lesion contrast improved by a factor of 2.8 for a nonradioactive rod of 6 mm diam. In phantom images, the elliptical orbit showed better definition of lesion shape, sharper edge response, and clearly increased detectability. Translational motion reduced ring artifacts, particularly near the image center.

Models, Structural

Immune regulatory abnormalities produced by procainamide.

The pathogenesis of procainamide-induced autoantibody production is unknown. To test the effect of procainamide on the immune system, we studied in vitro suppressor cell function and immunoglobulin G (IgG) secretion in 11 patients who developed autoantibodies while taking procainamide. The procainamide group was compared with patients with spontaneous systemic lupus erythematosus (n = 15) and a normal control population (n = 40). Impaired in vitro suppressor cell function was found in 11 of 14 patients with spontaneous systemic lupus erythematosus but in none of the patients taking procainamide. However, total in vitro IgG secretion was significantly increased in the procainamide group with regard to the control and systemic lupus erythematosus groups. There was a direct correlation between the circulating anti-SS DNA antibody titer and in vitro IgG secretion. Furthermore, T cells isolated from the procainamide-treated patients stimulated IgG secretion by normal allogeneic peripheral blood lymphocytes. The added T cells did not affect in vitro suppressor cell function. We postulate that autoantibody production in patients taking procainamide is due to enhanced helper T cell function and not to impaired suppression. However, the development of clinical disease requires the participation of additional genetic or immunologic factors.

Adolescent

Immunoglobulin E in serum and semen of infertile men.

Determination of IgE level in serum and semen of 92 men by an enzymatic immuno-assay method verified its presence in semen of most of them (92.3%) in much smaller amount than that present in serum (2.6%). IgE levels in serum and semen were significantly correlated. Serum levels were significantly higher in men with obstructive azoospermia, specially when associated with infection. Serum levels of IgE were higher in the fertile men, and in cases without infection as compared with those with prostatitis though this difference was not significant.

Adult