Tahir Tak

Comparison of Doppler echocardiographic and hemodynamic indexes of left ventricular diastolic properties in coronary artery disease

Transmitral flow velocity was measured by Doppler echocardiography in 15 patients with coronary artery disease simultaneously with high-fidelity recording of left ventricular pressure. Doppler echocardiographic recordings were also performed in 14 age- and heart rate-matched normal subjects. Statistically significant differences (p less than 0.05) in acceleration half-time (55.3 +/- 8.2 vs 70.4 +/- 14.9 ms), deceleration half-time (83.1 +/- 17.9 vs 109.5 +/- 18.1 ms), deceleration rate (4.9 +/- 0.9 vs 3.1 +/- 0.9 m/s2), peak velocity of early diastolic left ventricular inflow (E wave) (0.78 +/- 0.13 vs 0.61 +/- 0.13 m/s) and A/E ratio (0.74 +/- 0.20 vs 0.98 +/- 0.31) between normal subjects and patients were noted. There was no significant difference in peak velocity of atrial systolic flow (A wave) between normal subjects and patients. Correlation between transmitral flow indexes and hemodynamic indexes of left ventricular diastolic properties were poor, with r values ranging from 0.02 to 0.65. Significant correlations between deceleration rate versus maximal isovolumic left ventricular pressure decrease (maximum -dP/dt) and A wave versus maximum -dP/dt (p less than 0.05) were found (0.53 and 0.65, respectively). Deceleration rate was the most sensitive index of isovolumic relaxation assessed by hemodynamic methods, whereas the A/E ratio was a poor indicator of hemodynamic measurements of isovolumic relaxation. An abnormal deceleration rate had 100% specificity for detecting abnormal maximum -dP/dt, while abnormal acceleration half-time, deceleration half-time and A/E ratio had 80% specificity for detecting abnormal time constant. The deceleration rate, acceleration half-time, deceleration half-time and A/E ratio had a predictive value of 60 to 100% for the detection of abnormal maximum -dP/dt and time constant.

Comparison of transthoracic and transesophageal echocardiography in clinically overt or suspected pericardial heart disease.

Abstract Among these 42 patients, TEE was superior to TTE in detecting pericardial thickening (11 of 13 vs 5 of 13), intrapericardial metastases (13 of 13 vs 3 of 13), intrapericardial clot (5 of 5 vs 0 of 5), and pericardial cysts (1 of 1 vs 0 of 1), respectively. TEE added little to TTE in detecting pericardial effusions. The unavoidable bias in the interpretation due to the awareness of the clinical history before the echocardiograms is a limitation of the study.

Detection of acute myocardial infarction with digital image processing of two-dimensional echocardiograms

We have previously described the ability of a computer-based image digitizing system to assess early textural changes in acute canine myocardial infarction. To determine whether this technique could be applied to human beings, we studied 12 patients with a first acute transmural myocardial infarction and five normal subjects. Two-dimensional echocardiograms were performed on days 1 and 8 in normal subjects and on days 1 (day of admission), 2, 3, 5, and 14 in the patient population. All recording parameters on the echocardiography machine were kept identical for serial studies. The mean period between hospitalization and first echocardiogram was 11.1 hours (range 4 to 20 hours). End-diastolic frames from the two-dimensional echocardiographic images were digitized and displayed on a monitor. The mean pixel intensity (MPI) (+/- SD) in the region of asynergy (area of myocardial infarction) and a normal area were determined. In normal volunteers, no significant change in MPI was noted between anteroseptal and lateral areas on two separate two-dimensional echocardiographic studies, which were performed 7 days apart (anteroseptal: MPI, 21.6 +/- 1.1 vs 21.8 +/- 0.4, p = not significant) and (lateral: MPI, 21.5 +/- 1.2 vs 21.4 +/- 1.4, p = not significant). In patients with myocardial infarction, a significant increase in MPI was noted on the first day of myocardial infarction between normal and infarcted myocardium (20.4 +/- 2.0 vs 24.3 +/- 2.3, p less than 0.05) and progressively increased thereafter until day 14 (20.5 +/- 1.7 vs 31.9 +/- 3.7, p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Normalization of Doppler indices of diastolic dysfunction during pacing is a sign of ischemic mitral regurgitation

Twenty-three patients with angina who were undergoing diagnostic cardiac catheterization underwent cardiac pacing with simultaneous hemodynamic and Doppler echocardiographic evaluation to assess the effects of pacing-induced ischemic on mitral valve velocity. Seventeen patients had significant coronary artery disease, and six patients had normal coronary arteries. Doppler and hemodynamic measurements were performed at rest and immediately after pacing was discontinued to 91% +/- 7% of maximal predicted heart rate. Seven patients experienced new or significant increases in severity of mitral regurgitation after pacing as revealed by Doppler examination. This group had a significant increase (p = 0.007) in early but not in late peak filling velocities immediately after pacing was discontinued, with a resultant decrease in late to early ratios, which decreased from 1.01% +/- 0.12 to 0.70% +/- 0.19 (p = 0.006). Left ventricular end-diastolic pressure increased significantly from 16.7% +/- 6.8 mm Hg to 29.4% +/- 5.3 mm Hg after cardiac pacing (p less than 0.001). Patients with coronary disease who did not develop mitral regurgitation also had significant increases in left ventricular end-diastolic pressure from 18.7% +/- 5.8 mm Hg to 24.3% +/- 8.6 mm Hg (p less than 0.05). There were no changes in late or early wave amplitude, late to early ratio, or other Doppler measurements in any of the other groups. We conclude that mitral regurgitation caused by pacing-induced myocardial ischemia normalizes Doppler indices of mitral inflow, which in turn, may mask persistent or worsened left ventricular diastolic dysfunction.

Ultrasonic tissue characterization of the heart

P. A. N. CHANDRARATNA, M.D., JOIE PIERCE JONES, PH.D.,P SIDNEY LEEMAN, PH.D.,

Visualization and measurement of flow velocity and flow reserve in aortocoronary saphenous vein bypass grafts by transesophageal echocardiography.

TAHIR TAK, M.D., and SHAHBUDIN H. RAHIMTOOLA, M.B., F.R.C.P. Section of Cardiology, University of Southern California School of Medicine, Los Angeles, California, Department of Radiological Sciences, University of California, Irvine, California,? and Department of Medical Engineering and Physics, Kings College School of Medicine, London, United Kingdom.

Identification of Textural Differences of the Mitral leaflets in Subsets of Patients with Mitral Valve Prolapse

Transesophageal echocardiography was used to image bypass grafts and measure flow reserve in these conduits. Imaging and measurement of flow reserve were feasible in most patients.

Severity of Aortic Regurgitation Assessed by Digital Image Processing of Doppler Spectral Recordings.

In order to evaluate the effect of an increase in preload caused by contrast medium (Renografin‐75) on Doppler echocardiographic indices of left ventricular diastolic properties, left ventricular pressure using a catheter tip micromanometer and pulsed‐Doppler measurement of transmitral flow signals were measured simultaneously in 15 patients with coronary artery disease pre‐ and post‐left ventricular angiography. After left ventricular angiography, changes in indices determined from left ventricular pressure were significant: left ventricular end‐diastolic pressure increased from 17 ± 2 mmHg to 24 ± 2 mmHg (mean ± SE) (P < 0.001), maximum ‐dP/dt increased from 1,129 ± 63 to 1,307 ± 90 mmHg/sec (P < 0.005), and time constant decreased from 73 ± 2 to 67 ± 1 msec (P < 0.01). Changes in Doppler‐derived indices were also significant: A/E ratio decreased from 0.99 ± 0.08 to 0.81 ± 0.07 (P < 0.01), peak velocity of early diastolic filling increased from 0.61 ± 0.03 to 0.79 ± 0.03 M/sec (P < 0.01), and deceleration rate increased from 3.1 ± 0.2 to 4.6 ± 0.2 M/sec2 (P < 0.01). Changes in Doppler echocardiographic indices (DR, acceleration half time, deceleration half time, and A/E ratio) were accompanied by changes in time constant and maximum ‐dP/dt after left ventricular angiography. However, the correlations between changes in hemodynamic indices and changes in Doppler echocardiographic indices were poor (r = 0.06 to 0.67). We conclude that changes in Doppler indices of left ventricular diastolic properties are not satisfactory for evaluating changes in left ventricular end‐diastolic pressure, time constant, and maximum ‐dP/dt which reflects the limitation of these presently available parameters to assess diastolic function.

Origin and Site of the Tricuspid Regurgitant Jet Determined by Color Flow Imaging in Ebstein's Anomaly

FIGURE 3. Absent strut of the mitral Starr-Edwards prosthesis and disruption of the cloth covering from the strut mechanism. min. A pulsatile liver was noted. The prosthetic valve sounds were ioud and heard when entering the xoom. These sounds were “normal” to the patient. No precordial murmur was heard. Chest auscultation revealed bilateral scattered rales in the lower half of both lung fields. Chest x-ray revealed the mitral valve poppet to be in the left ventricular cavity (Fig. 11, Cardiac fluroscopy revealed the titanium ball to pop out of the cage in diastole and return and seat properly in the SE mitral valve prosthesis in systole (Fig. 2). At opera