Journal of the American College of Cardiology
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J. Am. Coll. Cardiol. · Dec 1990
Comparative Study Clinical TrialOrigin and significance of diastolic Doppler flow signals in the left ventricular outflow tract.
Diastolic Doppler flow signals (greater than or equal to 0.2 m/s) in the left ventricular outflow tract have not been well characterized, and their origin and significance remain controversial. Fifty-nine patients (55 +/- 16 years of age) with technically good Doppler echocardiographic studies were studied prospectively. There were 14 normal subjects, 21 patients with left ventricular hypertrophy, 10 with dilated cardiomyopathy and 14 with other cardiac disease. ⋯ The major determinants of diastolic outflow tract velocity were the mitral inflow E and A velocities and left end-diastolic dimension, particularly when combined (r = 0.64, p less than 0.0001 for E'; r = 0.72, p less than 0.0001 for A'). Distinctive E' and A' Doppler outflow tract signals result from mitral inflow and may be detected in most patients with normal heart size. These E' and A' velocities increase from apex to base and are more prominent in patients with a small, normally contracting heart or left ventricular hypertrophy.
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J. Am. Coll. Cardiol. · Dec 1990
Randomized Controlled Trial Multicenter Study Comparative Study Clinical TrialReduction in incidence of inducible ventricular tachycardia after myocardial infarction by treatment with streptokinase during infarct evolution.
The aim of this study was to determine whether intravenous streptokinase administered with or without oral aspirin to patients with evolving myocardial infarction reduces the inducibility of ventricular tachycardia at electrophysiologic study and thus the risk of sudden death in infarct survivors. Of 159 patients randomized at Westmead Hospital to the multicenter Second International Study of Infarct Survival (ISIS-2) after streptokinase and aspirin in acute myocardial infarction, 87 underwent electrophysiologic testing 6 to 28 days after infarction to determine their risk of subsequent ventricular arrhythmias (streptokinase 20 patients; aspirin 25 patients; streptokinase and aspirin 21 patients; both placebos 21 patients). Patients who underwent electrophysiologic testing had similar clinical characteristics to those of patients who did not. ⋯ During a mean follow-up period of 39 +/- 9 months, there were no spontaneous episodes of ventricular tachycardia, ventricular fibrillation or witnessed sudden death in the streptokinase-treated group compared with three such events in the placebo-treated group (p = 0.13). When compared with placebo therapy, intravenous streptokinase substantially reduced the incidence of inducible ventricular tachycardia in infarct survivors. No similar benefit was attributable to aspirin therapy.
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J. Am. Coll. Cardiol. · Dec 1990
Comparative Study Clinical TrialIntraoperative echocardiography in infants and children with congenital cardiac shunt lesions: transesophageal versus epicardial echocardiography.
To determine the utility and limitations of intraoperative transesophageal echocardiography in infants and children with congenital intracardiac shunts, intraoperative transesophageal (n = 50) and epicardial (n = 49) echocardiograms were performed before and after cardiopulmonary bypass in children from 4 days to 16 years old and 3 to 45 kg in body weight. A miniaturized transesophageal probe (6.9 mm maximal diameter) was used in 36 patients weighting less than or equal to 20 kg. Epicardial imaging was performed with a 5 MHz precordial probe. ⋯ These results demonstrated that intraoperative transesophageal echocardiography consistently defined important morphologic, color and pulsed Doppler ultrasound features of most congenital shunt lesions. Lesions that involved the right ventricular outflow tract are sometimes difficult to image with uniplane transesophageal echocardiography. There were no complications in any of the 50 subjects.
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J. Am. Coll. Cardiol. · Dec 1990
Comparative Study Clinical TrialPrevalence of additional cardiovascular anomalies in patients referred for transcatheter closure of patent ductus arteriosus.
Catheter closure of the patent ductus arteriosus is now a reality. The purpose of this study was to establish the prevalence of associated cardiovascular defects and the accuracy of echocardiography in patients referred for transvenous ductal closure. This study reviewed 146 patients seen from 1981 to 1988: 126 with only a patent ductus arteriosus (Group I) and 20 with additional cardiovascular anomalies (Group II). ⋯ Significant anomalies found at catheterization included two thoracic arteriovenous malformations and an isolated right carotid artery draining into the right pulmonary artery by way of a right ductus arteriosus. This study indicates that echocardiography is an effective diagnostic technique in this patient group. A thorough cardiac catheterization with angiography should be performed before implantation of a ductal device.
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J. Am. Coll. Cardiol. · Dec 1990
Comparative StudyDecreased operative risk of surgical treatment of mitral regurgitation with or without coronary artery disease.
The consecutive 2 year experience with patients undergoing first-time surgery for mitral regurgitation with and without coronary artery disease was reviewed. From January 1988 to January 1990, 127 patients with pure mitral regurgitation undergoing first-time operation were surgically treated. No other valve lesion, no reoperation and no congenital defects were included. ⋯ There was no significant difference in patients who either did or did not have a concomitant coronary artery bypass graft and there was no difference related to age or functional class. Postoperative complications occurred in five patients in the valve repair group, including recurrent mitral regurgitation in two necessitating reoperation, and in three patients in the valve replacement group. With newer operative and postoperative management techniques, especially preservation of the papillary muscle annular continuity, the risk of mitral valve surgery, particularly of valve repair, is considerably lower than in previous years.