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Dive into the research topics where Jung-Myung Lee is active.

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Featured researches published by Jung-Myung Lee.


American Journal of Cardiology | 1991

Pulmonary venous flow velocity pattern as assessed with transthoracic pulsed Doppler echocardiography in subjects without cardiac disease

Tohru Masuyama; Jung-Myung Lee; Masahiko Tamai; Jun Tanouchi; Akira Kitabatake; Takenobu Kamada

Pulmonary venous flow velocity pattern (PVFVP) was analyzed in 53 subjects (aged 25 to 77 years, mean 47) without cardiovascular disease who underwent transthoracic pulsed Doppler echocardiography. The forward flow velocity pattern was biphasic in 37 of the 53 subjects, with each of the 2 peaks in systole and diastole; flow was triphasic with 2 peaks in systole and the other peak in diastole in the remaining 16 subjects. Peak systolic and diastolic flow velocity ranged from 28 to 84 cm/s and from 27 to 71 cm/s, respectively. Mean systolic flow velocity was significantly greater than mean diastolic flow velocity (53 +/- 12 vs 47 +/- 11 cm/s, p less than 0.01). Systolic flow velocity and the ratio of systolic to diastolic flow velocity increased and diastolic flow velocity decreased with aging (r = 0.52, p less than 0.001, r = 0.70, p less than 0.001 and r = -0.49, p less than 0.001, respectively). Reverse flow occurred during the atrial contraction phase and its velocity (mean 20 cm/s) increased with aging (r = 0.56, p less than 0.001). The parameters of PVFVP were compared with the ratio of peak early diastolic filling velocity to peak filling velocity at atrial contraction (E/A ratio) measured in the transmitral flow velocity pattern. As E/A ratio increased, systolic flow velocity and systolic/diastolic flow ratio and peak reverse flow velocity decreased (r = -0.40, p less than 0.01, r = -0.67, p less than 0.001 and r = -0.68, p less than 0.001, respectively) and diastolic flow velocity increased (r = 0.58, p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)


American Heart Journal | 1995

Doppler echocardiographic pulmonary venous flow-velocity pattern for assessment of the hemodynamic profile in acute congestive heart failure

Tohru Masuyama; Jung-Myung Lee; Reiko Nagano; Kazunori Nariyama; Kazuhiro Yamamoto; Johji Naito; Toshiaki Mano; Hiroya Kondo; Masatsugu Hori; Takenobu Kamada

The hemodynamic profile of congestive heart failure (CHF) is best described in terms of its two primary sets of hemodynamic parameters, that is, left atrial pressure and cardiac output, each of which has a specific and independently variable hemodynamic cause. To assess whether analysis of the mitral and/or pulmonary venous flow-velocity patterns provides valuable information in the noninvasive assessment of the hemodynamic profile of CHF, these patterns were obtained by using the transthoracic approach in 18 patients with acute CHF with simultaneous measurements of catheter-derived mean pulmonary capillary wedge pressure and thermodilution cardiac index. Measurements were repeated on two occasions in each case: at the acute stage of CHF and 1 to 5 days after treatment. Peak diastolic pulmonary venous forward flow velocity was higher, the ratio of pulmonary venous systolic to diastolic peak forward flow velocity was lower, and the ratio of mitral early diastolic to late diastolic flow velocity was greater in patients with higher mean pulmonary capillary wedge pressure (r = 0.80, n = 36, p < 0.01; r = -0.69, n = 36, p < 0.01; r = 0.71, n = 36, p < 0.01). Peak systolic pulmonary venous forward flow velocity and time-velocity integral of the systolic pulmonary venous flow wave were greater in patients with larger cardiac index (r = 0.80, n = 36, p < 0.01; r = 0.62, n = 36, p < 0.01). In conclusion, two primary sets of hemodynamic parameters, that is, left atrial pressure and cardiac output, can be estimated with Doppler pulmonary venous flow parameters in patients with acute CHF.


Journal of The American Society of Echocardiography | 1994

Transthoracic Doppler assessment of pattern of left ventricular dysfunction in hypertensive heart disease : Combined analysis of mitral and pulmonary venous flow velocity patterns

Reiko Nagano; Tohru Masuyama; Jung-Myung Lee; Kazuhiro Yamamoto; Johji Naito; Toshiaki Mano; Hiroya Kondo; Masatsugu Hori; Takenobu Kamada

Although mitral flow velocity pattern changes with the progression of left ventricular (LV) diastolic dysfunction, it lacks predictive value in individual patients because of pseudonormalization in the presence of congestive heart failure and many physiologic and pathologic contributors to the mitral flow velocity pattern. To determine whether analysis of pulmonary venous flow velocity patterns complements the information obtainable from the mitral flow velocity patterns in the evaluation of patterns of LV dysfunction of hypertensive heart disease in individual patients, the ratio of the peak early diastolic filling velocity/peak filling velocity at atrial contraction (E/A ratio) in the mitral flow velocity pattern and the ratio of the peak systolic forward flow velocity (S)/peak diastolic forward flow velocity (D) (S/D ratio) in the pulmonary venous flow velocity pattern by the transthoracic approach were determined in 107 hypertensive patients with and without congestive heart failure. Age-related normal values of the E/A and S/D ratios were determined in 61 normal subjects and used to judge the normality or abnormality of the patterns. Results of the study indicate that (1) although an increased mitral E/A ratio is strongly indicative of heart failure with normal LV systolic function, the mitral E/A ratio is frequently within the normal range in hypertensive patients with heart failure; (2) association of decreased pulmonary venous S/D ratios with a normal mitral flow velocity pattern indicates the presence of heart failure as a result of LV systolic dysfunction that is usually observed at the most advanced pattern of LV dysfunction; (3) mild LV diastolic dysfunction is likely to exist in patients with normal E/A ratios if the pulmonary venous S/D ratio is higher than normal value; (4) predictive accuracy in the detection of LV systolic and diastolic dysfunction would be improved if both mitral and pulmonary venous flow velocity patterns rather than the mitral flow velocity pattern alone were analyzed. In conclusion, analysis of pulmonary venous flow velocity recordings improves accuracy and reliability of the Doppler assessment of LV systolic and diastolic dysfunction, particularly in individual hypertensive patients with normal mitral flow velocity patterns.


Journal of The American Society of Echocardiography | 1995

Transthoracic doppler echocardiographic measurements of pulmonary venous flow velocity patterns: Comparison with transesophageal measurements

Tohru Masuyama; Reiko Nagano; Kazunori Nariyama; Jung-Myung Lee; Kazuhiro Yamamoto; Johji Naito; Toshiaki Mano; Hiroya Kondo; Masatsugu Hori; Takenobu Kamada

Recently, we and other groups showed that analysis of transthoracic pulmonary venous flow velocity patterns is useful in the estimation of left ventricular diastolic function and left atrial pressure; however, it is unclear whether transthoracic tracings, in contrast to transesophageal tracings, provide reliable quantitation of the abnormal pulmonary venous flow characteristics in patients with and without cardiac disorders. This study was attempted to validate transthoracic pulmonary venous flow measurements by comparing them with transesophageal measurements in eight normal volunteers and 17 patients with a variety of cardiac disorders. Transesophageal and transthoracic measurements of peak diastolic forward flow velocity, the ratio of peak systolic/diastolic forward flow velocities, and the peak reversal flow velocity at atrial contraction sampled in the right upper pulmonary vein showed good correspondence to each other. The flow velocities were higher in the right upper pulmonary vein than in the left upper pulmonary vein. Narrower spectral flow velocity patterns with higher velocities were obtained 1 to 2 cm distal to the orifice in the pulmonary vein than at the orifice. Thus transthoracic measurements of the pulmonary venous flow velocity pattern are feasible and accurate in patients and may be used to assess left ventricular function and hemodynamics as a substitute for transesophageal measurements.


Cardiovascular Drugs and Therapy | 1997

Prediction of the changes in cardiac output in association with preload reduction therapy in patients with hypertensive heart failure

Reiko Nagano; Tohru Masuyama; Jung-Myung Lee; Kazuhiro Yamamoto; Johji Naito; Toshiaki Mano; Hiroya Kondo; Masatsugu Hori; Michitoshi Inoue; Takenobu Kamada

In treating patients with acute hypertensive heart failure we often try preload-reduction therapy using diuretics or vasodilators, but this may frequently produce a considerable decrease in cardiac output, particularly in hypertensive patients with diastolic dysfunction. Therefore, it is important from the clinical standpoint to predict the change in cardiac output following preload-reduction therapy. The objective of this study was to assess whether the change in cardiac output in association with preload-reduction therapy is predictable before treatment by analysis of mitral flow velocity patterns in patients with hypertensive heart failure. Changes in left ventricular volumes and cardiac output in association with preload-reduction therapy and Doppler echocardiographic parameters of the mitral flow velocity pattern before treatment were studied in 18 patients with hypertensive heart failure. Cardiac output increased in six patients with systolic dysfunction (fractional shortening <25%). In the other 12 patients (those with normal systolic function), the changes in cardiac output were homogenous among the patients. In this subset there was a greater decrease in cardiac output in patients with a shorter deceleration time. Thus, analysis of deceleration time of the early diastolic filling wave before treatment may be useful in estimating the change in cardiac output following preload reduction in patients with hypertensive heart failure due to diastolic dysfunction.


American Heart Journal | 1992

Analysis of pulmonary venous flow velocity patterns in hypertensive hearts: Its complementary value in the interpretation of mitral flow velocity patterns

Tohru Masuyama; Jung-Myung Lee; Kazuhiro Yamamoto; Jun Tanouchi; Masatsugu Hori; Takenobu Kamada


Pathophysiology | 1994

Enhanced left atrial conduit function in patients with congestive heart failure: A doppler echocardiographic study

Tohru Masuyama; Reiko Nagano; Jung-Myung Lee; Masatsugu Hori; Takenobu Kamada


American journal of noninvasive cardiology | 1994

Comparison of transesophageal and transthoracic Doppler echocardiographic measurements of mitral flow velocity patterns

Reiko Nagano; Hiroya Kondo; Masatsugu Hori; Takenobu Kamada; Tohru Masuyama; Kazunori Nariyama; Jung-Myung Lee; Kazuhiro Yamamoto; Johji Naito; Toshiaki Mano


Journal of the American College of Cardiology | 1991

Characteristic pulmonary venous flow velocity pattern in hypertensive hearts: Its complementary value in the interpretation of mitral inflow velocity pattern

Jung-Myung Lee; Tohru Masuyama; Jun Tanouchi; Akira Kitabatake; Takenobu Kamada


Japanese Circulation Journal-english Edition | 1989

-317-A NOVEL APPROACH TO MYOCARDIAL ISCHEMIA IN THE INFARCT AREA : AN EVALUATION BY INTRACORONARY VEIN ELECTROCARDIOGRAM : ECG, Mapping : FREE COMMUNICATIONS(II) : PROCEEDINGS OF THE 53th ANNUAL SCIENTIFIC MEETING OF THE JAPANESE CIRCULATION SOCIETY

Jouji Naito; Kazuo Komamura; Yasushi Okazaki; Jung-Myung Lee; Shinji Asada; Tomoki Ohara; Yasushi Matsumura; Kazuhiro Yamamoto; Kazuhiko Nishida; Shinsuke Nanto; Masayoshi Mishima; Kazuhisa Kodama

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Tohru Masuyama

Hyogo College of Medicine

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