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Aim: To evaluate the relationship between Doppler-derived left ventricular (LV) dP/dt and the degree of LV mechanical asynchrony measured by strain rate imaging., Methods and Results: The study group consisted of 69 patients with variable degree of LV dysfunction and mitral regurgitation (MR). Conventional echo variables and LV dP/dt were calculated from the MR Doppler spectrum by rate-pressure-rise method. Strain rate traces were obtained by 12-segment model and LV long axis images were analyzed off-line. The longest time intervals between the peak negative strain rate waves at isovolumic contraction period and peak systole from reciprocal segments were defined as asynchrony index AIc or AIs, respectively. The maximum differences in time-to-peak systolic velocities between opposing walls were also measured as asynchrony index by tissue Doppler (AItd). The dP/dt, mean QRS duration, AIc, AIs, and AItd were 836 +/- 266 mmHg/sec, 125 +/- 31, 38 +/- 28, 64 +/- 44, and 52 +/- 32 m, respectively. No significant correlation between the dP/dt and the LV dimension, ejection fraction or QRS duration was observed. However, dP/dt correlated negatively with AIc, or AIs (r:-0.78, -0.72, P < or = 0.0001) and AItd (r:-0.65, P < or = 0.001). A cutoff dP/dt value of under 700 mmHg/sec can discriminate patients over median AIs (55 ms) or patients with AIc over 30 ms with high sensitivity and specificity., Conclusions: Doppler-derived LV dP/dt is related to the degree of LV dyssynchrony rather than the conventional systolic function indices such as EF% in patients with severe heart failure. Noninvasive dP/dt assessment in addition to advanced imaging techniques can be used to define patients for cardiac resynchronization therapy (CRT).

Radiofrequency (RF) catheter ablation has become standard therapy for many types of arrhythmias. RF energy may cause deterioration in left ventricular function by damaging the myocardium. The aim of the present study was to assess the changes in left ventricular function after catheter ablation using various echocardiographic parameters. Forty patients (22 women), aged 37 +/- 14 years (range, 15-76 years), underwent catheter ablation for various tachycardias. Routine echocardiogaphic examination was done in all patients. Left ventricular systolic function was evaluated by the modified Simpson method and tissue Doppler. With regard to left ventricular diastolic function parameters, diastolic early (E) and late (A) transmitral filling velocities, deceleration time (DT), isovolumetric relaxation time (IVRT), and tissue Doppler parameters were assessed. All ventricular function parameters were assessed before, and 1 hour, 1 day, and 1 month after the catheter ablation procedure. To avoid any influence of heart rate on diastolic function parameters, the E/A ratio, DT, and IVRT were adjusted to heart rate (cE/A, cDT, cIVRT). No changes in left ventricular systolic function after the ablation were observed. After the ablation procedure (1 hour, 1 day, and 1 month) the cE/A ratio decreased from 1.42 +/- 0.43 to 1.19 +/- 0.40, 1.18 +/- 0.40, and 1.30 +/- 0.33 (P = 0.009), respectively. cDT increased from 210 +/- 54 to 272 +/- 64, 255 +/- 60, 240 +/- 64 (P = 0.001), respectively. Likewise cIVRT increased from 113 +/- 22 to 133 +/- 54, 123 +/- 27, 117 +/- 19 (P = 0.007), respectively. Significant changes were also observed concerning tissue Doppler parameters in assessing diastolic function. Although no significant changes were observed in systolic function after RF ablation, this procedure may have some detrimental effects on ventricular diastolic function para-meters.

Objective: To evaluate aortic function and its relation to left ventricular diastolic function in patients with hypertension, diabetes, or both, without coronary artery disease., Methods: Study groups were composed of 27 healthy participants and 25 patients with hypertension, 24 with diabetes, and 18 with hypertension and diabetes. Coronary artery disease was excluded in all of the study participants. Aortic strain and distensibility were calculated from the aortic diameters measured by echocardiography and blood pressure obtained by sphygmomanometry., Results: There were significant differences between the control and the patient groups (hypertensive, diabetic, and diabetic-hypertensive) in aortic strain (mean (SD) 18 (8)% v 11 (7)%, 9 (3)%, and 8 (3)%, respectively, p < 0.001) and distensibility (10 (5.1) v 3.1 (1.5), 5.1 (2.8), and 2 (0.9) cm2/dyn/10(3), respectively, p < 0.001). In a multivariate analysis, the parameter most closely related to the deceleration time in the control group was aortic distensibility (standardised beta coefficient -0.50, p = 0.002, overall R2 = 0.25). In the patient group, the parameter most closely related to deceleration time was also aortic distensibility (standardised beta coefficient -0.36, p = 0.009, overall R2 = 0.13). Even though the study group variable was entered in to the multivariate model, aortic distensibility was found to be the parameter most closely related to deceleration time (standardised beta coefficient -0.48, p < 0.001, overall R2 = 0.22)., Conclusion: Aortic stiffness is increased in patients with hypertension, diabetes, or both even after the exclusion of coronary artery disease. Aortic stiffness and left ventricular diastolic dysfunction are also associated in these patients.

Some patients with hypertrophic nonobstructive cardiomyopathy (HNCM) suffer symptoms resembling those in obstructive type despite no left ventricular outflow tract (LVOT) gradient could be detected on resting echocardiography. To investigate the value of dobutamine stress echocardiography (DSE) in determining the dynamic left ventricular (LV) obstruction of patients with HNCM. The study was conducted on 31 patients who were diagnosed HNCM on resting echocardiography and 9 healthy person as a control group. Intraventricular flow acceleration of > 3 m/sec on DSE was accepted as dynamic LVOT obstruction. Group 1 and 2 included patients without and with dynamic LVOT obstruction, respectively. The occurrence of chest pain and dyspnea seen during DSE was more frequent in group 2 than group 1 and control group. The frequency of SAM was significantly higher (p < 0.05) and the septal angle was significantly lower (p < 0.001) in Group 2. The presence of SAM significantly correlated with the peak gradient (r = 0.61, p < 0.001). The septal angle had significant negative correlations with the peak gradient (r = -0.77, p < 0.001) reached at DSE. The relative risk for peak gradient was highest when septal angle was < or = 100 degrees, with a sensitivity of 93%, specificity of 80%, positive predictive value of 82%, negative predictive value of 92%, and predictive accuracy of 87%. DSE is a reliable tool for the diagnosis of dynamic LV obstruction in patients with HNCM. The presence of SAM together with a low septal angle is highly predictive for the presence of a dynamic LVOT obstruction detected by DSE.

This study was designed to assess the reliability of the proximal isovelocity surface area (PISA) method for the estimation of shunt quantification in perimembranous ventricular septal defects (PVSD). The study group was composed of 30 patients (age 11 +/- 7 years, 13 female) with PVSD. The shunt flow (Qp-Qs) and the ratio of the pulmonary flow to the systemic flow (Qp/Qs) were calculated by spectral Doppler and catheterization. The Qp-Qs, the defect area (DA), and the shunt volume (SV) were obtained by the PISA method. The PISA method estimated the DA (cm(2)/m(2)), the SV (cm(3)/m(2)), and the Qp-Qs (L/min/m(2)) to be equal to (2 x pi x R(2) x NL)/(V(max) x Body surface area), DA x TVI(shunt), and to SV x Heart rate, respectively (R is the distance of the maximal PISA from the first aliasing line to the left ventricular side of the defect, NL is the nyquist limit, and V(max) and TVI(shunt) are the peak velocity and time-velocity integral of transdefect Doppler tracing obtained by continuous-wave Doppler). The PISA method (3.4 +/- 1.5 L/min/m(2)) underestimated the Qp-Qs according to spectral Doppler (r = 0.96, P < 0.001; mean difference -0.74 +/- 0.61 L/min/m(2); SEE = 0.11 L/min/m(2), P < 0.001) and catheterization (r = 0.92, P < 0.001; mean difference -0.45 +/- 0.7 L/min/m(2); SEE = 0.13 L/min/m(2), P < 0.001). The correlations between the PISA findings (Qp-Qs, DA, SV) and the catheterization Qp/Qs (r = 0.86, 0.84, and 0.86; P < 0.001, respectively), or between these and the spectral Doppler Qp/Qs (r = 0.80, 0.80, and 0.79; P < 0.001, respectively) were significant. The accuracies of the PISA findings in identifying large defects were high (0.90, 0.93, and 0.90 for cut-off values of Qp-Qs = 3.67 L/min/m(2), DA = 0.44 cm(2)/m(2), and SV = 43 cm(3)/m(2), respectively). As a result, the PISA method can be a simple and reliable alternative to the spectral Doppler method in the identification of large shunts in PVSD.