Journal of the American College of Cardiology
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J. Am. Coll. Cardiol. · Nov 1990
Direct visualization of ruptured chordae tendineae by transesophageal two-dimensional echocardiography.
To determine the value of transesophageal echocardiography in the detection of ruptured chordae tendineae, 28 patients who had surgical therapy for pure mitral regurgitation were evaluated prospectively by conventional transthoracic and transesophageal two-dimensional echocardiography. Seventeen patients (Group I) had ruptured chordae tendineae and 11 (Group II) had intact chordae tendineae. ⋯ No abnormal chordal echoes were visualized in any patient from Group II by either transthoracic or transesophageal echocardiography (specificity 100%). Transesophageal echocardiography is a highly sensitive method for detecting ruptured chordae tendineae and is superior to transthoracic echocardiography in establishing its diagnosis.
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J. Am. Coll. Cardiol. · Nov 1990
Instantaneous and continuous cardiac output in humans obtained with a Doppler pulmonary artery catheter.
A new Doppler pulmonary artery catheter was used to measure instantaneous and continuous cardiac output in both an in vitro model and in 44 patients undergoing cardiac catheterization. Cardiac output was calculated with use of the Doppler catheter-determined instantaneous space-average velocity and the ultrasonically determined instantaneous vessel area. Doppler flow and thermodilution were compared with electromagnetic flow in the in vitro model and with Fick cardiac output in patients. ⋯ However, predictive accuracy was comparable to simultaneously obtained thermodilution measurements (r = 0.85, m = 1.07 and SEE = 0.10; mean error +/- SEM = 0.61 +/- 0.16 liters/min). This new Doppler catheter system utilizes multiple ultrasound transducers to provide angle-independent measurements of vessel diameter and instantaneous velocity within the main pulmonary artery, resulting in a more accurate assessment of Doppler-derived cardiac output. In addition, useful information concerning hemodynamic variables such as peak flow, acceleration, deceleration, stroke work and pulmonary impedance may be derived.
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J. Am. Coll. Cardiol. · Nov 1990
Comparative Study Clinical TrialSimultaneous transesophageal atrial pacing and transesophageal two-dimensional echocardiography: a new method of stress echocardiography.
The diagnostic use of exercise echocardiography has been widely reported. However, transthoracic exercise echocardiography is inadequate in up to 20% of patients because of poor image quality related to exercise. In an attempt to overcome these limitations, a system was developed in which transesophageal echocardiography is combined with simultaneous transesophageal atrial pacing by means of the same probe. ⋯ Thus, rapid atrial pacing combined with simultaneous transesophageal echocardiography is a highly specific and sensitive technique for the detection of coronary artery disease. Ischemia-induced wall motion abnormalities were detected earlier than observed ECG changes. The technique appears to be particularly suited to patients who are unable to perform an active stress test or those with poor quality transthoracic echocardiograms.