The American journal of cardiology
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Randomized Controlled Trial Comparative Study Clinical Trial
Comparative evaluation of a new formulation of isosorbide dinitrate oral spray and sublingual nitroglycerin tablets.
The magnitude and time course of the hemodynamic effect of a new formulation of an aqueous solution of isosorbide dinitrate (ISDN) spray were compared with those of sublingual nitroglycerin (NTG) tablets in 12 patients with chronic congestive heart failure. The patients received, in a random order, ISDN spray, 2.5 mg, or sublingual NTG, 0.8 mg. Hemodynamic measurements were performed before and at 1, 3, 5, 10, 20, 30 and 60 minutes after each drug. ⋯ The peak effect of ISDN spray on PCWP and right atrial pressure was greater than that of NTG. Thus, the onset of the hemodynamic effect of the new formulation of ISDN spray is much more rapid than that of sublingual NTG tablets. At the doses used, the magnitude of the effect of the ISDN spray on some of the hemodynamic variables is greater than that of sublingual NTG.
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Randomized Controlled Trial Clinical Trial
A dose-finding study of the hemodynamic effect of isosorbide dinitrate spray in congestive heart failure.
A dose-finding study of the hemodynamic effect of a new formulation of isosorbide dinitrate (ISDN) spray was performed in 12 patients with chronic congestive heart failure. Doses of 1.25, 2.5, 5.0 mg and placebo, as 1 squirt, were randomly given to all patients. Hemodynamic measurements were performed by a Swan-Ganz catheter before and at 30 seconds and 1, 5, 10, 20 and 30 minutes after drug administration and every 30 minutes thereafter, until return of hemodynamic variables to baseline. ⋯ Near maximal effect was achieved by the 2.5-mg dose. Thus, 2.5 mg of ISDN spray (new formulation) dose. Thus, 2.5 mg of ISDN spray (new formulation) produces rapid, near-maximal hemodynamic improvement in patients with congestive heart failure.
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Review Randomized Controlled Trial Clinical Trial
Low-dose warfarin and low-dose aspirin in the primary prevention of ischemic heart disease.
The thrombotic component in ischemic heart disease (IHD) is now universally recognized. It is therefore logical to consider modifying both fibrin formation and platelet function in primary (as well as secondary) prevention. The scientific case for evaluating lower-dose warfarin in primary prevention rests on the implications of the secondary prevention trials, increasing evidence of an association between the level of factor VII coagulant activity, VIIc, and the incidence of IHD, and the results of short-term lower-dose trials for the prevention of venous thrombosis and thromboembolism. ⋯ The objective of the factorial Thrombosis Prevention Trial is to demonstrate a reduction in the incidence of IHD in men at high risk attributable to low-dose warfarin or low-dose aspirin, or both, with 1 group receiving both active treatments. The feasibility of this trial has been demonstrated. An International Normalized Ratio of about 1.5, achieved with an average daily dose of 4.6 mg warfarin, has resulted in no increase in the number of men ever reporting minor bleeding episodes, although rectal bleeding occurs more frequently in those men who do report this symptom.
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Randomized Controlled Trial Multicenter Study Clinical Trial
Efficacy and safety of intravenous diltiazem for treatment of atrial fibrillation and atrial flutter. The Diltiazem-Atrial Fibrillation/Flutter Study Group.
This study evaluates the effectiveness and safety of intravenous diltiazem for the treatment of atrial fibrillation and atrial flutter. A double-blind, parallel, randomized, placebo-controlled protocol was used, and 6 large, urban hospitals, both university-affiliated and private, participated. The study involved 113 patients with atrial fibrillation or flutter, a ventricular rate greater than or equal to 120 beats/min and systolic blood pressure greater than or equal to 90 mm Hg without severe heart failure. ⋯ Thus, intravenous diltiazem was rapidly effective for slowing the ventricular response in most patients with atrial fibrillation or atrial flutter. Blood pressure decreased slightly. Side effects were mild.
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Randomized Controlled Trial Clinical Trial
Evaluation by exercise Doppler echocardiography of maintenance of cardiac output during ventricular pacing with or without chronotropic response.
To examine the effectiveness of activity-initiated rate-responsive pacing, this study assessed the increases in stroke volume and cardiac output during randomized treadmill exercise in rate-responsive and fixed-rate ventricular (VVI) pacing in 10 patients. Stroke volume index and cardiac index were determined by suprasternal Doppler measurements. ⋯ These findings indicate that VVI pacing increased stroke volume more than did rate-responsive pacing, especially in younger patients, but the increase in cardiac output was less than that seen with rate-responsive pacing due to the absence of chronotropic response. Accordingly, an activity-sensing, rate-responsive pacemaker can effectively increase the heart rate, significantly augment cardiac output and extend the duration of exercise.