Clinical cardiology
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Clinical cardiology · Jan 1997
Transesophageal pulsed Doppler echocardiographic evaluation of left atrial systolic performance in hypertrophic cardiomyopathy: combined analysis of transmitral and pulmonary venous flow velocities.
Hypertrophic cardiomyopathy (HC) is characterized by impaired left ventricular (LV) diastolic function due to an increase in LV wall thickness. The severity of this disease varies depending on the localization and extent of the hypertrophied myocardium and the presence and extent of myocardial disarray or fibrosis. ⋯ Peak velocity and duration of TMF and PVF during atrial systole by transesophageal pulsed Doppler echocardiography are useful indices of hemodynamic abnormalities between the left atrium and the left ventricle during atrial systole, particularly a forceful atrial contraction mismatched to the left atrial afterload and severity of LV diastolic dysfunction, in HC.
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Clinical cardiology · Jan 1997
Abnormal signal-averaged electrocardiograms in patients with incomplete right bundle-branch block.
A hypothesis was formulated that regional delayed activation of the right ventricle, as seen in incomplete right bundle-branch (IRBBB) aberrancy, may simulate late potential activity and may be responsible for abnormal signal-averaged electrocardiograms (SAECGs). No previous studies have specifically addressed this issue in this particular group of patients (with IRBBB). Therefore, the aim of the present study was to investigate the incidence of abnormal SAECGs in patients with IRBBB. If this were confirmed, our purpose would further be to investigate ways of reducing the false positive results. ⋯ Delayed terminal conduction observed in IRBBB may cause a high incidence of false positive late potentials on SAECGs. Based on this study, we propose that this can be largely remedied if the optimal criteria for the presence of late potentials in patients with IRBBB always include the combination of QRSD and either RMS or LAS.
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Clinical cardiology · Jan 1997
Retrograde atrial kick in acute aortic regurgitation. Study of mitral and pulmonary venous flow velocities by transthoracic and transesophageal echocardiography.
The purpose of this study was the comprehensive evaluation of the changes in pulmonary venous and mitral flow velocities of patients with acute and chronic severe aortic regurgitation. Transmitral flow velocities obtained with pulsed-wave Doppler echocardiography have been used to provide information on left ventricular (LV) filling and diastolic function. Pulmonary venous flow tracings are an important adjunct to LV inflow pattern in assessing LV diastolic function. ⋯ Patients with severe acute aortic regurgitation showed a retrograde atrial kick (absence of transmitral A wave with prominent pulmonary AR wave). These patients had an S/D ratio < 1 (restrictive Doppler pattern). Patients with chronic aortic regurgitation exhibited a Doppler pattern of abnormal LV relaxation (E/A < 1, S/D > 1).