The American journal of cardiology
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To determine the relation of Doppler findings to clinical outcome and the agreement between Doppler and cardiac catheterization in the assessment of aortic stenosis (AS) severity, 510 consecutive patients with suspected AS studied in our laboratory were analyzed. Adequate echocardiographic and Doppler examinations were obtained in 498 patients or 98% of the population. Clinical data were available for analysis in 497 patients. ⋯ In 20 patients, aortic valve replacement was performed because of moderate to severe aortic regurgitation, and in 11 elderly (greater than 70 years old) patients with valve areas between 0.80 and 1.0 cm2, valve replacement was performed at the time of coronary artery bypass surgery in an attempt to prevent the need for a repeat surgical procedure in the future. These observations allow the following conclusions. In the symptomatic patient with critical or near critical AS by Doppler, cardiac catheterization does not provide additional information beyond that provided by Doppler.(ABSTRACT TRUNCATED AT 250 WORDS)
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Randomized Controlled Trial Comparative Study Clinical Trial
Cardiac Arrest in Seattle: Conventional Versus Amiodarone Drug Evaluation (the CASCADE study).
This randomized study evaluates survivors of out-of-hospital ventricular fibrillation (VF) not associated with a Q-wave acute myocardial infarction who are deemed to be at a high risk of recurrence of VF. It compares the outcome of treatment with empirically administered amiodarone with the outcome of treatment with other antiarrhythmic agents guided by electrophysiologic testing or Holter recording, or both. The goal of therapy guided by electrophysiologic testing is to suppress inducible ventricular tachycardia (VT) or VF. ⋯ Baseline clinical characteristics remain similar in amiodarone and conventional drug groups. Pulmonary toxicity with amiodarone is 7% at 1 year, with no patients dying of pulmonary toxicity. In the first 142 patients, the overall 1-year cardiac mortality was 19%, with a 17% arrhythmic mortality (either VF or presumed arrhythmic death).(ABSTRACT TRUNCATED AT 250 WORDS)
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Comparative Study Clinical Trial
The unstable ST segment early after thrombolysis for acute infarction and its usefulness as a marker of recurrent coronary occlusion.
To investigate the incidence of early recurrent ST elevation after intravenous thrombolytic therapy for acute myocardial infarction, 12-lead electrocardiograms were continuously monitored for 571 +/- 326 minutes in 31 patients presenting within 4 hours of symptom onset. The study group comprised 9 women and 22 men (mean age +/- standard deviation 53 +/- 12 years), with ST elevation (anterior in 15, inferior in 16) on the initial electrocardiogram, who were given either tissue plasminogen activator (22 patients) or streptokinase (9 patients). Angiography was performed in 30 of 31 patients at 7 to 10 days. ⋯ The proportion of silent episodes was similar for transient (35%) and sustained (33%) recurrences. All patients with sustained recurrent ST elevation had at least 1 preceding transient recurrence. The median duration of transient recurrent ST elevation was 43 minutes (28 to 63).(ABSTRACT TRUNCATED AT 250 WORDS)
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Comparative Study Clinical Trial Controlled Clinical Trial
Hemodynamic effects of ketamine, hypoxia and hyperoxia in children with surgically treated congenital heart disease residing greater than or equal to 1,200 meters above sea level.
Little data are available on the hemodynamic effects of premedications and anesthetic agents on infants and children. Ketamine is the most frequently used anesthetic agent for cardiac catheterization procedures in pediatric patients with congenital heart disease. Previous reports both suggest and deny ketamine's pulmonary vasoreactive effects. ⋯ The hyperresponders had an elevated resistance ratio (0.42) in room air and a striking reaction to hypoxia (+0.65), hyperoxia (-0.17) and ketamine (+0.49). Hypoxia and ketamine have a greater effect on resistance ratio than hypoxia alone in patients with reactive pulmonary vascular beds. Ketamine should not be used in children undergoing procedures to establish operability based on pulmonary vascular resistance or pulmonary vascular reactivity.
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To examine the effects of beta-adrenergic blockade on neurohormonal activation in patients with congestive heart failure, 15 men had assessments of hemodynamics and supine peripheral renin and norepinephrine levels before and after 3 months of oral therapy with bucindolol, a nonselective beta antagonist. At baseline, plasma renin activity did not correlate with any hemodynamic parameter. However, norepinephrine levels had a weak correlation with left ventricular end-diastolic pressure (r = 0.74, p less than 0.01), stroke volume index (r = 0.61, p less than 0.02) and pulmonary vascular resistance (r = 0.54, p less than 0.05). ⋯ Although plasma norepinephrine did not decrease, heart rate tended to decrease (from 82 +/- 20 vs 73 +/- 11 min-1, p = 0.059) with beta-adrenergic blockade, suggesting neurohormonal antagonism at the receptor level. No changes in I-123 metaiodobenzylguanidine uptake occurred after bucindolol therapy, suggesting unchanged adrenergic uptake of norepinephrine with beta-blocker therapy. Despite reductions in plasma renin activity and the presence of beta blockade, the response of renin or norepinephrine levels to long-term bucindolol therapy did not predict which patients had improved in hemodynamic status (chi-square = 0.37 for renin, 0.82 for norepinephrine).(ABSTRACT TRUNCATED AT 250 WORDS)