Yuichiro Mishiro

PULSED TISSUE DOPPLER IMAGING OF LEFT VENTRICULAR SYSTOLIC AND DIASTOLIC WALL MOTION VELOCITIES TO EVALUATE DIFFERENCES BETWEEN LONG AND SHORT AXES IN HEALTHY SUBJECTS

Our objective was to evaluate in healthy subjects the left ventricular (LV) wall motion velocities along the long and short axes by means of pulsed tissue Doppler imaging (TDI) to clarify the differences in the LV systolic and diastolic function between both axes. Wall motion velocities were recorded at the mid-wall portion of the middle site of the LV posterior wall in the parasternal long-axis view, and at the subendocardial portion of the middle site of the LV posterior wall in the apical long-axis view by pulsed TDI in 35 healthy subjects (mean age 26 +/- 10 years, mean heart rate 72 +/- 7 bpm). In all subjects, the LV pressure curve, its first derivative (dP/dt), the LV wall motion velocity, the phonocardiogram, and the electrocardiogram were simultaneously recorded. The systolic wave of the LV posterior wall motion velocity exhibited 2 peaks: the first and second systolic waves (Swl and Sw2, respectively). The diastolic wave also exhibited 2 peaks, the early diastolic and atrial systolic waves. The Swl along the long axis was greater than either the Sw1 and Sw2 along the short axis or the Sw2 along the long axis. The peak Sw1 along the long axis coincided with the peak dP/dt and was slightly earlier than the peak Swl along the short axis. The onset of Sw1 along the long axis coincided with the onset of the first heart sound. The Sw2 along the short axis was greater than that along the long axis. The early diastolic wave along the short axis was greater than that along the long axis, whereas the atrial systolic wave along the long axis was greater than that along the short axis. Thus, in healthy subjects, shortening of the longitudinal fibers predominated over that of the circumferential fibers during early systole, whereas shortening of the circumferential fibers predominated over the longitudinal fibers during the ejection phase. During diastole, the circumferential fibers predominated in the LV wall expansion at early diastole, whereas the longitudinal fibers predominated at atrial systole. In conclusion, pulsed TDI provided information that is useful in understanding the characteristics of LV wall motion along the long and short axes.

Effect of aging on diastolic left ventricular myocardial velocities measured by pulsed tissue Doppler imaging in healthy subjects.

We evaluated the effect of aging on diastolic left ventricular (LV) wall motion velocity in 80 healthy persons with the use of pulsed tissue Doppler imaging. The wall motion velocity patterns were recorded at the middle regions of the LV posterior wall and ventricular septum in the parasternal (along the short axis) and apical (along the long axis) LV long-axis views. In the posterior wall, the peak early diastolic wall motion velocities (Ews) along both axes correlated inversely with age (long axis: r = -0.61, P <. 0001; short axis: r = -0.55, P <.0001), and the peak atrial systolic wall motion velocities(Aws) along both axes correlated directly with age (long axis: r = 0.59, P <.0001; short axis: r = 0.65, P <.0001). In the ventricular septum, the Ew along the long axis correlated inversely with age (r = -0.51, P <.0001), and the Aws along both axes correlated directly with age (long axis: r = 0.57, P <.0001; short axis: r = 0.53, P <.0001). The Ews along both axes at the posterior wall correlated directly with the peak early diastolic transmitral flow velocity. The Aws along both axes at the ventricular septum and posterior wall correlated directly with the peak atrial systolic transmitral flow velocity. The times from the second heart sound to the peak of the early diastolic waves of the ventricular septum and posterior wall along both axes significantly increased with age. The times from the aortic component of the second heart sound to the peak of the early diastolic motion velocities along both axes were significantly longer at the ventricular septum than at the posterior wall. Pulsed tissue Doppler imaging may be useful for evaluating the effect of aging on diastolic LV function in healthy persons.

Left ventricular diastolic properties of hypertensive patients measured by pulsed tissue Doppler imaging.

Examination of left ventricular (LV) diastolic dysfunction in hypertensive patients has been based on parameters obtained from the transmitral flow velocity during pulsed Doppler echocardiography. However, these parameters are affected by loading conditions. We evaluated LV diastolic function along the longitudinal and transverse axes by pulsed tissue Doppler imaging (TDI) in 50 hypertensive (HT) patients and 36 age-matched healthy volunteers (N). Transmitral flow velocity was recorded by pulsed Doppler echocardiography. LV posterior wall motion velocity along the longitudinal and transverse axes also was recorded by pulsed TDI. In both groups, peak early diastolic velocity of the LV posterior wall (Ew) along the transverse axis (N: 15.8+/-5.2 cm/s, HT: 12.2+/-4.4 cm/s) was higher than that along the longitudinal axis (N: 12.7+/-3.1 cm/s, HT: 9.5+/-3.3 cm/s). Peak atrial systolic velocity of the LV posterior wall (Aw) along the longitudinal axis (N: 9.1+/-1.8 cm/s, HT: 9.7 +/-2.6 cm/s) significantly exceeded that along the transverse axis (N: 8.0+/-2.2 cm/s, HT: 8.4+/-2.4 cm/s) in both groups. The Ews were lower and the Aws were higher along both axes in the patient group than in the control group. The time intervals from the aortic component of the second heart sound to the peak of the early diastolic wave (IIA-Ews) along both the transverse (N: 142+/-18 ms, HT: 154+/-19 ms) and longitudinal (N: 151 16 ms, HT: 162+/-20 ms) axes were longer in the patient group. In 29 patients, Ews along both axes correlated negatively (transverse: r = -0.80, P < .0001; longitudinal: r = -0.71, P < .0001) and IIA-Ews correlated positively (transverse: r = 0.81, P < .0001; longitudinal: r = 0.74, P < .001) with the time constant of the LV pressure decay during isovolumic diastole. The Aws along both axes in the 24 patients without pseudonormalization in transmitral flow velocity correlated positively (transverse: r = 0.60, P < .001; longitudinal: r = 0.74, P < .0001) with the LV end-diastolic pressure. In conclusion, LV relaxation and filling along the longitudinal and transverse axes were impaired in many patients with hypertension. Pulsed TDI was useful for evaluating LV diastolic dynamics in this disease.

Evaluation of Left Ventricular Contraction Abnormalities in Patients with Dilated Cardiomyopathy with the Use of Pulsed Tissue Doppler Imaging

The left ventricular (LV) systolic wave, as recorded by pulsed tissue Doppler imaging, usually consists of 2 components (Sw(1) and Sw(2)). However, the clinical significance of these waves has not been studied in patients with dilated cardiomyopathy (DCM) and sinus rhythm. We studied 25 patients with DCM (DCM group) and 22 age-matched normal subjects (control group). The LV posterior wall motion velocities along the short and long axes were recorded by pulsed tissue Doppler imaging, and the peak velocities of the Sw(1) and Sw(2) and the times from the electrocardiographic Q wave to the peak Sw(1) and Sw(2) (Q-Sw(1) and Q-Sw(2), respectively) were determined. In all patients cardiac catheterization was performed immediately after the noninvasive examination, and the LV end-diastolic pressure and peak dP/dt were determined. The LV end-diastolic pressure and peak dP/dt were significantly greater and lower, respectively, in the DCM group. The peak Sw(1) along the long axis was significantly greater than Sw(1) and Sw(2) along the short axis and Sw(2) along the long axis in the control group. The peak Sw(1) and Sw(2) along the long and short axes were all significantly lower in the DCM group than in the control group. The Q-Sw(1) along the long axis was significantly shorter than that along the short axis, whereas no significant difference was seen in the Q-Sw(2) in either axis in any patient. The Q-Sw(1) and Q-Sw(2) along both axes were significantly longer in the DCM group than in the control group. All systolic pulsed tissue Doppler imaging variables, particularly the peak Sw(1) along the long axis, correlated well with the peak dP/dt in all patients. LV contractility along both the short and long axes is commonly impaired in patients with DCM. In particular, peak Sw(1) along the long axis is a useful parameter for evaluating LV myocardial contractility during isovolumic contraction.

Influence of Aging on Systolic Left Ventricular Wall Motion Velocities Along the Long and Short Axes in Clinically Normal Patients Determined by Pulsed Tissue Doppler Imaging

Our objective was to evaluate the influence of aging on left ventricular (LV) regional systolic function along the long and short axes in clinically normal patients. We recorded LV wall motion velocity patterns at the mid-wall portion of the middle of the LV posterior wall in the parasternal long-axis view (short-axis direction) and at the endocardial portion of the middle of the LV posterior wall in the apical long-axis view (long-axis direction) with pulsed tissue Doppler imaging in 80 normal patients (age range 15 to 78 years). In all patients the LV pressure curve and its first derivative (dP/dt) were recorded. The systolic wave of the LV posterior wall motion velocity pattern exhibited 2 peaks, the first (Sw(1)) and second (Sw(2)) systolic waves. No significant changes were seen with aging in the percent LV fractional shortening determined by M-mode echocardiography, LV ejection fraction determined by left ventriculography, the peak Sw(1) and Sw(2) along the short axis, the peak Sw(2) along the long axis, and the peak dP/dt. The peak Sw(1) along the long axis correlated inversely with age (P <.0001) but did not correlate significantly with the peak dP/dt. These results suggest that shortening of the longitudinal fibers in early systole is impaired with increased age in healthy individuals. This impairment results in insufficient spherical change in the LV cavity, although global LV pump function and myocardial contractility are maintained.

Effect of an Acute Increase in Afterload on Left Ventricular Regional Wall Motion Velocity in Healthy Subjects

We recorded left ventricular (LV) wall motion velocities before and after angiotensin II infusion by pulsed tissue Doppler imaging in 20 healthy subjects, and evaluated the responses of systolic and diastolic LV function along the long and short axes during an acute increase in afterload. Angiotensin II was administered intravenously to obtain a 30% increase in mean blood pressure. After angiotensin II infusion, LV end-systolic dimension and end-systolic circumferential wall stress increased significantly, and the percentage of LV fractional shortening decreased significantly. Peak first systolic LV wall motion velocity (Sw1 ) along the long axis decreased markedly compared with that along the short axis, and peak second systolic LV wall motion velocity (Sw2 ) along the short axis decreased significantly compared with that along the long axis. Early diastolic LV wall motion velocities along both the long and short axes decreased significantly, whereas atrial systolic LV wall motion velocity did not change. In conclusion, an acute increase in afterload caused a significant decrease in longitudinal fiber shortening during the isovolumic contraction phase (Sw1 along the long axis), circumferential fiber shortening during the ejection phase (Sw2 along the short axis), and LV relaxation during early diastole (early diastolic LV wall motion velocities along both axes) in healthy subjects. Pulsed tissue Doppler imaging may be useful for detecting the effect of various loading conditions on LV wall motion velocities along the long and short axes.

Detection of left ventricular regional relaxation abnormalities and asynchrony in patients with hypertrophic cardiomyopathy with the use of tissue Doppler imaging

BACKGROUND It is well known that the distribution and magnitude of left ventricular (LV) hypertrophy are not uniform in patients with hypertrophic cardiomyopathy (HCM), which results in regional heterogeneity of LV early diastolic function. The advent of tissue Doppler imaging (TDI) has allowed the noninvasive evaluation of regional LV wall motion velocities. The aim of this study was to evaluate regional LV relaxation abnormalities and asynchrony noninvasively in patients with HCM by using pulsed and color-coded TDI. METHODS AND RESULTS We studied 20 patients with asymmetric septal hypertrophy (HCM group) and 18 age-matched normal patients (control group). The peak early diastolic motion velocity (Ew) and time from the aortic component of the second heart sound to the peak of the Ew (II(A)-Ew) were measured by pulsed TDI. The myocardial velocity gradient during early diastole (MVG-Ew) also was measured by color-coded TDI. Mean values for these parameters were determined on the basis of measurements made at 2 sites of the ventricular septum or posterior wall at the levels of chordae tendineae and papillary muscles. The mean Ew and mean MVG-Ew for the ventricular septum and posterior wall were significantly lower, and mean II(A)-Ew was significantly prolonged in the HCM group compared with the control group. This difference was most pronounced in the hypertrophied ventricular septum of the HCM group. The standard deviations of II(A)-Ew for the ventricular septum and posterior wall were significantly greater in the HCM group than in the control group. The time constant of LV pressure decay during isovolumic diastole (tau) correlated inversely with Ew and MVG-Ew and correlated directly with II(A)-Ew. Furthermore, tau correlated directly with the standard deviation of the II(A)-Ew. CONCLUSIONS LV early diastolic function in patients with HCM may be mediated by an augmentation of regional LV relaxation abnormalities and asynchrony.

Effects of additional administration of low-dose indapamide on patients with hypertension treated with angiotensin II receptor blocker.

Background: Low-dose thiazide or thiazide-like diuretics have proven useful for the management of blood pressure in patients older than 65 years (elderly group). However, there are few reports about the antihypertensive effects of antihypertensive diuretic agents in patients younger than 65 years (middle-aged group). So, we evaluated the efficacy of low-dose indapamide on blood pressure. Methods: Indapamide(1 mg) was given daily for 3 months and was then given every other day for 3 months to patients whose hypertension was poorly controlled with angiotensin II receptor blocker (ARB)-based treatment. Results: After daily administration of indapamide, blood pressure was significantly decreased in both the middle-aged and elderly groups. Blood pressure was not significantly changed by every-other-day administration compared with that observed after daily administration in either group. The rate of attainment of the target blood pressure was 90.3% and 85.7% in the middle-aged and elderly groups, respectively. The serum uric acid levels were reduced after every-other-day administration compared to daily administration but tended to be higher than the levels at the baseline in both groups. Conclusions: The addition of low-dose indapamide is a useful strategy for the management of hypertension, as it reduced blood pressure without marked side effects.