Journal of the American College of Cardiology
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J. Am. Coll. Cardiol. · Oct 1983
Two-dimensional echocardiographic assessment of bioprosthetic valve dysfunction and infective endocarditis.
Two-dimensional echocardiography of Hancock porcine heterograft valves was evaluated by correlation with clinical, hemodynamic, angiographic and pathologic findings in 80 patients. Ninety-five aortic and mitral bioprostheses were categorized by the type of valvular abnormality: group I, dysfunction due to primary tissue failure (41 valves); group II, dysfunction due to paravalvular leakage without infection (5 valves); group III, infective endocarditis with or without hemodynamic dysfunction (28 valves); and group IV, control cases without dysfunction or infection (21 valves). Increased size of a bioprosthetic leaflet image (minimal dimensions 3 x 5 mm) was observed in 46% (19 of 41) of cases with primary tissue failure and in 62% (10 of 16) of cases with leaflet vegetations due to endocarditis. ⋯ Antegrade extension of leaflet echoes to beyond the level of the stents, observed in 4 of 16 cases with leaflet vegetations, was the only echocardiographic sign distinguishing leaflet infection from leaflet degeneration. Aortic bioprostheses with ring dehiscence affecting 40 to 90% of the anular circumference showed motion discordant with the motion of the adjacent aortic root and native anulus. Although echocardiographic abnormalities are frequently observed with bioprosthetic leaflet degeneration or infection, the echocardiographic appearance often does not distinguish between these two major complications and is best interpreted concurrently with other clinical and laboratory assessment.
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J. Am. Coll. Cardiol. · Sep 1983
Detailed analysis of 24 hour ambulatory electrocardiographic recordings during ventricular fibrillation or torsade de pointes.
Although the terminal cardiac rhythm is often well documented in many cases of sudden cardiac death, the antecedent or premonitory arrhythmias are usually not retrievable. The ambulatory electrocardiographic recordings of 12 patients who sustained ventricular fibrillation or torsade de pointes while wearing a long-term electrocardiographic monitor were analyzed in detail. A printout of the entire electrocardiographic recording was made and hand counts of ventricular arrhythmias were correlated with heart rate, QTc interval, RR interval preceding ventricular fibrillation or torsade de pointes and (RR')/QT initiating ventricular fibrillation or torsade de pointes. ⋯ No consistent relation between the RR and RR' interval initiating ventricular fibrillation or torsade de pointes was found; no consistent alteration in heart rate occurred before ventricular fibrillation or torsade de pointes. Thus, ventricular arrhythmias leading to sudden death in an ambulatory population do not occur in isolation but are preceded by a period of increased ventricular ectopic activity. Future guidelines for assessment of antiarrhythmic drug efficacy should include an evaluation of a drug's impact not only on ectopic beat frequency but also on arrhythmia density.
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J. Am. Coll. Cardiol. · Mar 1983
Case ReportsEchocardiographic detection of pneumomediastinum and pneumopericardium: the air gap sign.
Six patients referred for echocardiographic evaluation in whom an unusual echocardiographic sign resulted from air within the mediastinum or pericardium are described. Three patients had a pneumomediastinum that occurred after chest trauma and three patients had a pneumopericardium induced during a therapeutic pericardiocentesis. Important features included a broad band of echoes (air) recorded during held respiration which obscured the normal cardiac structures and dropout (gap) of echoes posteriorly. ⋯ Echocardiographic recording of the air gap sign was identical in the six cases; it disappeared after resolution of clinical signs and symptoms of the pneumopericardium or pneumomediastinum. The pattern most likely resulted from air within the anterior mediastinum or pericardium interfering with the echographic beam and resulted in a cyclic appearance from systole to early diastole as the air was displaced by the changing cardiac size. Recognition of the air gap sign can be helpful in evaluating patients for pneumomediastinum or pneumopericardium after thoracic trauma.