Amplitudes, durations, and timings of apically directed left ventricular myocardial velocities: I. Their normal pattern and coupling to ventricular filling and ejection

The reduction of the left ventricular long-axis early diastolic peak velocity (e') evident by early-middle age occurs in the absence of aging-related slowing of active relaxation

PURPOSE

A decrease in the left ventricular (LV) long-axis early diastolic peak velocity (e') is evident by early-middle age, but it is unknown to what extent this decrease is due to slowing of the speed of active relaxation versus a reduction in LV long-axis excursion during early diastole (EDExc).

METHODS

Pulsed-wave tissue Doppler imaging (TDI) signals were acquired from the septal and lateral borders of the mitral annulus in 62 healthy adult subjects of age 18-45 years. EDExc and LV systolic excursion (SExc) were measured as the integrals of the respective TDI signals. The speed of active relaxation was indirectly assessed using time interval measurements related to the TDI early diastolic signal, including the isovolumic relaxation time (IVRT'), the acceleration time (EDAT), and the duration (EDDur). Multiple linear regression analyses were performed to identify the relationships between e', age, EDExc, SExc, and time intervals.

RESULTS

The findings were similar for both LV walls. Age was negatively correlated with e' and EDExc, but was not correlated with SExc, IVRT', EDAT, or EDDur. The closest correlate of EDExc was SExc, and EDExc was independently correlated with both SExc and age. e' was also positively correlated with SExc, but the closest correlate of e' was EDExc, and when combined with EDExc, EDDur became an independent predictor of e'.

CONCLUSION

The aging-related decrease in e' evident by early-middle age occurs in the absence of aging-related slowing of active relaxation and therefore can be largely attributed to the accompanying reduction in EDExc.

Assessment of Myocardial Ischemic Memory Using Three-Dimensional Speckle-Tracking Echocardiography: A Novel Integrated Analysis of Early Systolic Lengthening and Postsystolic Shortening

BACKGROUND

Persistence of subtle abnormal myocardial deformation such as postsystolic shortening (PSS) after transient ischemia can be used to diagnose a history of myocardial ischemia (myocardial ischemic memory). Furthermore, early systolic lengthening (ESL) has recently attracted attention as another marker of myocardial ischemia. However, it is unclear whether the persistence of such abnormal deformation can be detected by three-dimensional (3D) speckle-tracking echocardiography, which has relatively low spatial and temporal resolution compared with two-dimensional echocardiography. The aim of this study was to evaluate the diagnostic accuracy of myocardial ischemic memory and its spatial extent using 3D speckle-tracking echocardiography.

METHODS

The left circumflex coronary artery was occluded for 2 min, followed by reperfusion, in 33 dogs. Their hemodynamic and 3D echocardiographic data were chronologically acquired. Peak systolic strain, early systolic strain index as a parameter of ESL, postsystolic strain index as a parameter of PSS, and myocardial dysfunction index as a combined parameter of ESL and PSS were analyzed in all left ventricular segments.

RESULTS

At the center of the risk area, early systolic strain index and postsystolic strain index significantly increased until 20 min after reperfusion compared with baseline, although peak systolic strain recovered by 20 min. Myocardial dysfunction index significantly increased for >20 min after reperfusion and allowed better diagnostic accuracy of ischemic memory than the other parameters. In the 147 risk segments, abnormal values of myocardial dysfunction index remained in 49 segments (33%) at 20 min after reperfusion, whereas abnormal peak systolic strain was observed in only 13 segments (9%).

CONCLUSIONS

ESL and PSS persisted after transient ischemia and could be detected by 3D speckle-tracking echocardiography. Integrated analysis of ESL and PSS provided higher diagnostic accuracy of ischemic memory. This method may be useful for detecting transient ischemic insults in patients after the disappearance of anginal attack.

Left Ventricular Septolateral Mechanical Delay Is Associated with Reduced Long-Term Survival in Systolic Heart Failure with Narrow QRS Duration: Nine-Year Outcome in 109 Patients

BACKGROUND

The long-term prognostic importance of left ventricular (LV) dyssynchrony in patients with systolic heart failure is not known. We investigated this question in 109 consecutive patients with systolic heart failure with an LV ejection fraction (EF) ≤35% and QRS duration <130 ms.

METHODS

The cohort is a prospective series of 109 patients with EF ≤35% and QRS duration <130 ms who did not receive a defibrillator. Onset to onset septolateral and anteroposterior mechanical delays were computed from tissue Doppler velocity signals of the four quadrants of the mitral annulus and related to mortality.

RESULTS

Patient characteristics included age 53 ± 12 years, 73% male, 23% with coronary artery disease, LVEF 24 ± 7%, LV end-diastolic dimension 64 ± 9 mm, LV end-systolic dimension 55 ± 9 mm, QRS duration 107 ± 30 ms, and 92 with QRS duration <120 ms. Over a follow-up of 9 years, there were 51 deaths. Univariate predictors of mortality included LV septolateral delay (HR 1.01 per ms, P < 0.0001), anteroposterior delay (P = 0.003), and age (P = 0.005), but not EF, LV size, or QRS duration. Using Cox regression analysis, LV septolateral delay was an independent predictor of higher mortality (P = 0.0005) after adjusting for age, gender, EF, LV size, QRS duration, coronary artery disease, diabetes mellitus, and use of beta blockers or angiotensin-converting enzyme inhibitors.

CONCLUSION

In patients with heart failure, LVEF ≤35% and QRSd < 130 ms, LV mechanical dyssynchrony is a strong and independent predictor of long-term mortality.

The tissue Doppler imaging derived post-systolic velocity notch originates at the aortic annulus

Background

A distinct velocity pattern represented by a "notch" is observed during the time interval between the end of the systolic and the onset of the early diastolic velocity wave on longitudinal myocardial velocity curve. The origin of the post-systolic velocity notch (PSN) has not been resolved.

Methods

The high frame rate color tissue Doppler imaging of the apical longitudinal axis was performed in 32 healthy subjects.

Results

The time delays of the PSN onset at the posterior aortic wall (AW), the mid anteroseptal wall (MAS) and the posterior mitral annulus (MA) relatively to the anterior aortic annulus (AA) were found to be significantly longer than zero (5.1 ± 2.2, 6.0 ± 2.3, 6.8 ± 2.8 ms; p < 0.001). The amplitude was the highest at the AA when compared to the AW, the MAS and the MA (4.77 ± 1.28 vs. 2.88 ± 1.11, 2.15 ± 0.73, 2.44 ± 1.17 cm/s; p < 0.001). A second PSN spike was identifiable in 10/32 (31%) of the studied subjects at the AA. Of these, 9 (28%) exhibited a second PSN spike at the AW, 3 (9%) at the MAS and no one at the MA.

Conclusion

The AA represents the site of the earliest onset and maximal amplitude of the PSN on the longitudinal velocity curve suggesting its mechanism to be that of an energy release at the instant of the aortic valve closure causing an apically directed acceleration of the myocardium. A substantial number of healthy subjects exhibit a second PSN spike predominantly at the level of the AA. Its mechanism remains to be elucidated.

Ultra-high frame rate tissue Doppler imaging

We describe a new tissue Doppler imaging (TDI) method, ultra-high frame rate tissue Doppler imaging (UFR-TDI). With two broad transmit beams covering only the ventricular walls, we achieve 1200 frames/s in a four-chamber apical view. We examined 10 healthy volunteers to study the feasibility of this method. Ultra-high-frame-rate TDI provided peak annular velocities and time to peak S' intervals in good agreement with those measured with conventional TDI. Moreover, UFR-TDI provided additional information in early and late systole: In all subjects, the method was able to separate the timing of electrical activation, start of mechanical contraction, mitral valve closure and start of ejection. The earliest mechanical activation was seen before mitral valve closure. The method was also able to measure the propagation speed of the mechanical wave created by aortic valve closure.

Treatment with atorvastatin is associated with a better prognosis in chronic heart failure with systolic dysfunction: results from The Daunia Heart Failure Registry

BACKGROUND

Few works have evaluated the effect of statins on left ventricular dysfunction in patients with chronic heart failure (CHF), by using tissue Doppler imaging (TDI). We therefore aimed to investigate whether atorvastatin treatment may influence prognosis and myocardial performance evaluated by TDI in subjects with CHF.

METHODS

Five hundred thirty-two consecutive CHF outpatients enrolled in a local registry, the Daunia Heart Failure Registry, were prospectively analysed. 195 patients with CHF and left ventricular ejection fraction (LVEF) ≤40 %, either in treatment with atorvastatin (N: 114) or without statins (N: 81), underwent TDI examination. Adverse events were evaluated during follow-up.

RESULTS

The atorvastatin group showed a lower incidence of adverse events (cardiac death: 0 % vs 7 %, p < 0.01), and better TDI performance (E/E' 15 ± 5.7 vs 18 ± 8.3, p < 001) than controls. Ischaemic CHF patients in treatment with atorvastatin also showed a lower incidence of adverse events (death: 10 % vs 26 %, p < 0.05; sustained ventricular arrhythmias: 5 % vs 19 %, p < 0.05, cardiac death: 0 vs 8 %, p < 0.05) and better TDI performance (E/E' ratio: 15.00 ± 5.68 vs 19.72 ± 9.14, p < 0.01; St: 353.70 ± 48.96 vs 303.33 ± 68.52 msec, p < 0.01) than controls. The association between atorvastatin and lower rates of cardiac death remained statistically significant even after correction in a multivariable analysis (RR 0.83, 95 % CI 0.71-0.96, p < 0.05 in CHF with LVEF ≤40 %; RR 0.77, 95 % CI 0.62-0.95, p < 0.05 in ischaemic CHF with LVEF ≤40 %).

CONCLUSIONS

Treatment with atorvastatin in outpatients with systolic CHF is associated with fewer cardiac deaths, and a better left ventricular performance, as assessed by TDI.

Left Ventricular Diastolic Function Assessment Using the Timing of Mitral Annular and Transmitral Flow Velocities

Background and aims:

Evaluation of left ventricular (LV) diastolic function plays an important role in clinical echocardiography. The relationship between mitral annular velocities from tissue Doppler imaging (TDI) (E′ and A′) and mitral inflow velocities (E and A) from Doppler echocardiography (DE) provide additional information about LV filling and diastolic function. The aims of this study are to i) assess the time differences between peak E and peak E′, peak A and peak A′, peak Ar and peak A, and ii) examine the effects of age and gender on these time intervals parameters in normal subjects.

Methods:

A total of 117 healthy subjects (age ranging from 22- to 78-years-old) were recruited for a standard of echocardiogram (ECHO). During early diastole, the time intervals from the peak of R-wave on the ECG to the peak of E-wave (R-pE), to the peak of E wave to peak of E′-wave (R-pE′) were measured. During late diastole, the time intervals from the onset of P-wave on the ECG to the peak A-wave (P-pA), to the peak Ar-wave on the pulmonary valve flow (P-pAr), to the peak A′-wave (P-pA′) were measured. Early-diastolic temporal discordance (EDTD) and late-diastolic temporal discordance (LDTD) were calculated as the differences between (R-pE) and (R-pE′), and (P-pA) and (P-pA′), respectively.

Results:

The mean EDTD and LDTD were 28.7 ± 10.6 ms and 21.2 ± 15.9 ms, respectively. Similarly, the mean time difference [(P-pA) - (P-pAr)] was 21.5 ± 14.1 ms. EDTD was not associated with age (r=0.15, p=NS), while LDTD was inversely correlated with age (r=-0.65, p<0.01). No significant differences were found for both EDTD and LDTD between genders.

Conclusion:

EDTD and LDTD, the temporal discordances between mitral annulus motion and trans-mitral flow, embody one of the earliest events at early- and late-diastole. Age is not associated with EDTD, but is accompanied by a decline in LDTD. With respect to gender, both EDTD and LDTD are not influenced.

Normal values of left and right ventricular function measured by M-mode, pulsed doppler and Doppler tissue imaging in healthy term neonates during a 1-year period

BACKGROUND

The measurements of left and right ventricular functions change after birth due to the influence of several hemodynamic changes upon the immature myocardium.

AIM

The aim of this study was to investigate the changes in left (LV) and right ventricular (RV) functions of healthy term newborns using conventional and Doppler echocardiography during a 1-year period.

SUBJECTS AND METHODS

Fifty healthy term newborns were examined prospectively on the first day, 3-4, 6-7, 9-10 and 11-12 months of their lives by M-mode, pulsed Doppler (PD) and Doppler tissue imaging techniques (DTI). PD velocities were obtained from mitral and tricuspid valves while DTI velocities were obtained from the lateral annuluses of atrioventricular valves.

RESULTS

EF and FS did not change significantly by time. Early (E) flow velocity and early myocardial (Em) velocity were higher than late (A) flow velocity and atrial systolic (Am) velocity for LV, while A and Am velocities were higher than E and Em velocities for RV, respectively during the study period. E, A, Em, Am, Sm velocities and Em/Am ratios increased while E/Em ratios decreased significantly by time (P<0.05) for both ventricle. However, E/A ratios of LV and RV did not change significantly by time. Myocardial performance index (MPI), obtained by PD for RV and by DTI for LV, decreased significantly by time (P<0.05) and these DTI values were higher than PD values during the study period.

CONCLUSIONS

Due to hemodynamic and maturation change of myocardium PD and DTI velocity changes took place during the first year of life which reflects differences in ventricular adaptation.

Use of echocardiography to evaluate the cardiac effects of therapies used in cancer treatment: what do we know?

Cardiologists and oncologists today face the daunting challenge of identifying patients at risk for late-onset left ventricular (LV) systolic dysfunction from the use of various chemotherapeutic agents. Currently, the most widely used method in clinical practice for monitoring the potential of chemotherapy-induced cardiotoxicity is calculation of LV ejection fraction. The use of LV ejection fraction to determine whether to continue or discontinue the use of chemotherapeutic agents is limited, because decreases in LV ejection fraction frequently occur late and can be irreversible. These limitations have led to the exploration of diastolic function and newer modalities that assess myocardial mechanics to identify sensitive and specific variables that can predict the occurrence of late systolic function. The cancer therapies associated with cardiotoxicity are reviewed in this report. Additionally, the authors evaluate the role of present-day echocardiographic parameters, complementary noninvasive imaging modalities, and biomarkers in the prediction of cardiotoxicity. The authors address the evolving role of cardioprotective agents and potential therapies to prevent or reverse the progression of LV systolic dysfunction. Finally, they provide some ideas regarding future directions to enhance the knowledge of predicting late-onset LV systolic dysfunction secondary to cancer therapy.

Tissue Doppler time intervals predict the occurrence of rehospitalization in chronic heart failure: data from the daunia heart failure registry

BACKGROUND

Patients with chronic heart failure (HF) are often rehospitalized; rehospitalization identifies subjects with a poorer quality of life and a worse prognosis. Estimates of the time intervals by tissue Doppler imaging (TDI) in patients with chronic HF has not been fully investigated, despite recent studies having explored the prognostic role of TDI-derived parameters in major cardiac diseases, such as HF. We, therefore, aimed to assess the prognostic value of time intervals evaluated by TDI in patients with chronic HF.

METHODS

A total of 249 patients with chronic HF enrolled in the Daunia Heart Failure Registry underwent echocardiography assessment and were followed prospectively for a mean 284 ± 210 days. Conventional echocardiography and TDI parameters were calculated; time intervals were calculated by TDI: ST (systolic time), ET (ejection time), FT (filling time), and ICT (isovolumic contraction time). We also have calculated ICT/ET and tissue myocardial performance index ([ICT+IRT]/ET).

RESULTS

At univariate analysis, ET (RR: 0.80, 95% confidence interval [CI] 0.71-0.90, P < 0.001), ST (RR: 0.88, 95% CI 0.78-0.99, P < 0.05), FT (RR: 0.88, 95% CI 0.78-0.99, P < 0.05), ICT/ET (RR: 1.21, 95% CI 1.07-1.37, P < 0.01) were related to the occurrence of rehospitalization during follow-up. At multivariate Cox regression analysis, correlations remained significant for ET and ST (P < 0.05 and P < 0.01, respectively).

CONCLUSIONS

Time intervals assessed by TDI may be helpful in predicting the risk of rehospitalization in subjects with chronic HF.

Statin therapy blunts inflammatory activation and improves prognosis and left ventricular performance assessed by Tissue Doppler Imaging in subjects with chronic ischemic heart failure: results from the Daunia Heart Failure Registry

BACKGROUND

A limited number of studies have used Tissue Doppler Imaging (TDI) to evaluate the effect of statin therapy on left ventricular dysfunction in patients with chronic heart failure. In this work, we aimed to determine whether statin administration influenced prognosis, inflammatory activation and myocardial performance evaluated by Tissue Doppler Imaging in subjects enrolled in the Daunia Heart Failure Registry, a local registry of patients with chronic heart failure.

METHODS

This study retrospectively analyzed 353 consecutive outpatients with chronic heart failure (mean follow-up 384 days), based on whether statin therapy was used. In all patients, several Tissue Doppler Imaging parameters were measured; circulating levels of interleukin (IL)-6, IL-10 and C-reactive protein were also assayed.

RESULTS

Statin administration in 128 subjects with ischemic heart disease was associated with a lower incidence of adverse events (rehospitalization for HF 15% vs. 46%, p<0.001; ventricular arrhythmias 5% vs. 21%, p<0.01; cardiac death 1% vs. 8%, p<0.05), lower circulating levels of IL-6 (p<0.05) and IL-10 (p<0.01), lower rates of chronic heart failure (p<0.001) and better Tissue Doppler Imaging performance (E/E' ratio 12.82 ± 5.42 vs. 19.85 ± 9.14, p<0.001; ET: 260.62 ± 44.16 vs. 227.11 ± 37.58 ms, p<0.05; TP: 176.79 ± 49.93 vs. 136.7 ± 37.78 ms, p<0.05 and St: 352.35 ± 43.17 vs. 310.67 ± 66.46 ± 37.78 ms, p<0.05).

CONCLUSIONS

Chronic ischemic heart failure outpatients undergoing statin treatment had fewer readmissions for adverse events, blunted inflammatory activation and improved left ventricular performance assessed by Tissue Doppler Imaging.

Analysis of the origin of cardiac wall motion that constitutes myocardial velocity-time curves in patients with left bundle branch block

Septal and lateral wall myocardial velocity-time curves from tissue Doppler imaging were analyzed to determine wall motion from which the velocity originated in 34 patients with left bundle branch and systolic dysfunction (ejection fraction < 45%). Longitudinal strain rate by speckle tracking imaging was assessed to identify whether corresponding wall motion was active or passive. All lateral peak velocities during the ejection period were derived from delayed active movement. However, septal peak velocities were more numerous and complex. Septal peak velocities during pre-ejection were derived from the first active movement in 29 patients (85.2%). Septal peak velocities during the ejection period were derived from the second active movement in 20 patients, passive movement in 9 patients, and first active movement in 5 patients. Because septal peak velocities were consistent with various wall motion types, identification of the origin of septal peak velocities, including during pre-ejection, may be important in identifying LV dyssynchrony based on the propagation of first active myocardial movements.

Noninvasive evaluation of left ventricular noncompaction: what's new in 2009?

Significant interest in clinical practice as well as the medical literature exists regarding the presentation and outcome of children and adults with left-ventricular noncompaction (LVNC). The mainstay in the diagnosis of LVNC has been the anatomic definition of the ventricular myocardium by two-dimensional echocardiographic imaging. Although helpful, this approach lacks diagnostic precision and fails to evaluate the functional impact of this abnormal myocardial architecture on global and regional myocardial performance. This review will focus on the use of novel echocardiographic modalities of tissue Doppler, strain, and strain rate imaging to identify and characterize abnormalities of regional myocardial function in patients with LVNC.

Clinical significance of positive isovolumetric relaxation velocity of pulsed-wave tissue Doppler imaging

OBJECTIVE

Among the pulsed-wave tissue Doppler imaging (pw-TDI) parameters, there are two different pw-TDI velocities (IVRa and IVRb) after systolic velocity, but before Ea velocity. In our study, we investigated the clinical importance of these two velocities in left ventricular diastolic dysfunction (LVDDF) evaluation.

METHODS

One hundred and eighty cases without exclusion criteria were included in the study. Cases with a transmitral E to A flow (E/A) ratio below 1 were assigned to group 2. In cases with an E/A ratio between 1 and 2, the pw-TDI parameters were taken into consideration. Cases with an Ea/Aa ratio above 1 were assigned to group 1 and cases with an Ea/Aa ratio 1 or below than 1 were assigned to group 3. Group 1 (n: 68) represented normal diastolic left ventricular (LV) inflow while group 2 (n = 87) represented impaired relaxation and group 3 (n = 25) represented pseudonormal LV inflow.

RESULTS

In our study, we found that IVRa velocity was lower in group 1 compared to group 2 and group 3 (P < 0.001 and P = 0.038, respectively). Similarly, this velocity was significantly different in group 3 and group 2 such as it was higher in group 2 compared to group 3 (P = 0.022). There was no difference in IVRb velocity and IVRa/IVRb ratio among the groups. A negative correlation was found between IVRa velocity and Ea velocity (r = 44%, P < 0.001). Positive correlation was found between IVRa velocity and isovolumetric relaxation time (r = 18%, P = 0.014) and also between IVRa velocity and Aa velocity (r = 19%; P = 0.010).

CONCLUSION

Based on the results of our study, we concluded that IVRa velocity is an important pw-TDI parameter in the evaluation of LVDDF, especially in differentiating pseudonormal LVDDF type from normal LV inflow.

Effect of left ventricular dyssynchrony on plasma B-type natriuretic peptide levels in patients with long-term right ventricular apical pacing

Right ventricular apical pacing (RAP) has been reported to have the potential to lead to left ventricular (LV) dyssynchrony and impaired LV function. The plasma level of B-type natriuretic peptide (BNP) is increased in the state of abnormal ventricular wall stretch. Therefore, the aim of the present study was to examine the effect of LV dyssynchrony on BNP levels in patients with chronic RAP. Thirty-four patients (17 women, age 69 +/- 11 years) with preserved LV systolic function on permanent RAP (duration, 7.0 +/- 4.7 years) underwent conventional echo-Doppler assessment and tissue Doppler imaging. Twenty-two normal subjects (8 women, age 66 +/- 9 years) served as controls. The standard deviation (SD) and dispersion of the time-to-peak systolic velocity (TPV) among the 6 basal LV segments were used as the indexes of LV dyssynchrony. Compared with control subjects, RAP patients had prolonged TPVs and heterogeneous LV contraction with greater values of TPV-SD (18 +/- 8 ms versus 39 +/- 15 ms, P < 0.001) and TPV-dispersion (42 +/- 20 ms versus 93 +/- 31 ms, P < 0.001). There were significant correlations between BNP levels and the indexes of LV dyssynchrony (r = 0.41, P = 0.017 for TPV-SD; r = 0.46, P = 0.006 for TPV-dispersion). RAP is associated with LV dyssynchrony, which may accelerate BNP secretion.

Assessment of diastolic ventricular function in fetuses of diabetic mothers using tissue Doppler

OBJECTIVE

To identify the presence of ventricular diastolic dysfunction by tissue Doppler in fetuses of diabetic mothers, with or without septal hypertrophy, in comparison to fetuses of nondiabetic mothers.

METHODS

A contemporary transverse study in fetuses with a gestational age between 25 weeks to term, studying diastolic function by assessment using tissue Doppler and pulsed wave Doppler of the atrioventricular diastolic flow. The mothers of the fetuses all had previous or gestational diabetes, and were referred to the Fetal Cardiology Unit of the Institute of Cardiology in Porto Alegre, Brazil. We analysed variance with the Student-Neumann-Keuls post hoc test. An alfa of 0.05 was considered significant for statistical analysis.

RESULTS

The mean myocardial velocities of the E'and A' waves at the mural mitral annulus, in fetuses of diabetic mothers with myocardial hypertrophy, were, respectively, 7.00 plus or minus 1.6 centimetres per second, and 10.24 plus or minus 3.3 centimetres per second. In the fetuses of diabetic mothers group without myocardial hypertrophy, the comparable values were 7.19 plus or minus 2.4 centimetres per second and 10.77 plus or minus 3.77 centimetres per second, respectively. In the control group, they were 4.81 plus or minus 0.85 centimetres per second and 8.01 plus or minus 2.2 centimetres per second. The difference between the velocities in fetuses of diabetic mothers and in fetal normal mothers was statistically significant (p less than 0.05). Statistically significant differences were also observed in E' and A' diastolic waves at the aortic mitral annulus, as well as for the tricuspid annulus when tissue Doppler assessment was carried out in the same sample. The mean ratio between the E and E' of mitral and tricuspid waves in the control fetuses of normal mothers was significantly higher than in fetuses of diabetic mothers.

CONCLUSION

Pulsed tissue Doppler, when used in fetuses of diabetic mothers and compared with fetuses of nondiabetic mothers, shows evidence of impaired diastolic function, independently of the presence of myocardial hypertrophy.

Exaggerated exercise blood pressure response is related to tissue Doppler imaging estimated diastolic dysfunction in the early stages of hypertension

We investigated the plausible interrelationship of exaggerated blood pressure response (EBPR) during exercise with left ventricular (LV) diastolic dysfunction, both associated with adverse cardiovascular outcomes, in the early stages of essential hypertension (EH). Sixty-five consecutive patients (aged 54 years, 56 males) with stage I to II EH underwent 24-hour ambulatory blood pressure (BP) recording and treadmill exercise testing and were classified as subjects with (n = 21) and without EBPR (n = 44) based on the systolic BP elevation at peak exercise (>/=210 mm Hg for men and >/=190 mm Hg for women). LV diastolic function was estimated by pulsed tissue Doppler imaging (TDI), averaging diastolic mitral annular velocities (Em, Am) from four separate sites (LV lateral, septal, anterior, and inferior wall). Hypertensives with EBPR, compared with those without EBPR, exhibited increased 24-hour pulse pressure by 4.8 mm Hg (P < .05) and significantly lower values of Em/Am ratio by 0.07 (P < .05). Univariate logistic regression analysis revealed that only 24-hour pulse pressure (odds ratio [OR] = 1.069; P = .043) and Em/Am (OR = 0.041; P = .049) were independent predictors of EBPR. Hypertensives with EBPR compared to their counterparts without EBPR are characterized by more pronounced LV diastolic dysfunction - assessed by TDI. Moreover, the increased pulsatile load seems to be a common denominator of these hypertension-linked states.

Age dependency in the timing of mitral annular motion in relation to ventricular filling in healthy subjects: Umea General Population Heart Study

AIMS

Peak left ventricular (LV) relaxation normally precedes peak filling (E), which supports the hypothesis that LV suction contributes to early-diastolic filling. The significance of similar temporal discordance in late diastole has previously not been studied. We describe the time relationships between mitral annular motion and LV filling in early and late diastole and examine the effect of normal ageing on these time intervals.

METHODS AND RESULTS

A total of 128 healthy subjects aged 25-88 years were studied. Transmitral and pulmonary venous flow reversals (Ar) were recorded by Doppler echocardiography. Mitral annular diastolic displacement-early (E(m)) and late (A(m))-were recorded by Doppler tissue imaging. With reference to electrocardiographic R and P-waves, the following measurements were made: R to peak E-wave (R-E) and E(m) (R-E(m)); onset P to peak A-wave (P-pA), A(m) (P-pA(m)), and Ar (P-pAr). The differences between [(R-E) and (R-E(m))] for early-diastolic temporal discordance (EDTD) and [(P-A) and (P-A(m))] for late-diastolic temporal discordance (LDTD) were calculated. Isovolumic relaxation time (IVRT) was also measured. Early-diastolic temporal discordance was approximately 26 ms in all age groups. Late-diastolic temporal discordance, however, was inversely related to age (r = -0.35, P < 0.001) and IVRT (r = -0.34, P < 0.001) and therefore decreased in the elderly vs. young (13 +/- 10 vs. 23 +/- 10 ms; P < 0.001). In multivariate analysis, age failed to predict LDTD in the presence of IVRT. A, A(m), and Ar were simultaneous at onset, and peak A(m) coincided with peak Ar in all age groups (r = 0.97, P < 0.001). No significant differences were noted in the RR intervals.

CONCLUSIONS

Sequential prolongation of IVRT with ageing reduces LDTD, thus converging the peaks of A(m), A, and Ar (atrial mechanical alignment)-a potential novel method to identify subjects at increased dependency on atrial contraction for late-diastolic filling.

The Mitral Annular Middiastolic Velocity Curve: Functional Correlates and Clinical Significance in Patients with Left Ventricular Hypertrophy

BACKGROUND

Little is known regarding the tissue Doppler characteristics and clinical significance of mitral annular motion during diastasis (L' wave).

METHODS

In consecutive patients with left ventricular hypertrophy and normal ejection fraction, standard Doppler and Doppler tissue imaging were performed. Patients were followed up for heart failure (HF) hospitalization.

RESULTS

Of 177 patients, 53 (30%) had an L', detected most frequently at the lateral mitral annulus, whereas 35 (20%) had middiastolic transmitral flow (L wave), which almost invariably coexisted with the L'. The L' predicted increased left ventricular filling pressure with 74% sensitivity and 82% specificity, and increased risk of future HF (hazard ratio 3.9 [P = .030]), even after adjusting for baseline clinical differences (hazard ratio 6.5 [P = .024]). When associated with an L wave, HF risk increased further.

CONCLUSIONS

Middiastolic annular motion, detectable in almost a third of patients with left ventricular hypertrophy, may be an early marker of diastolic dysfunction and a prognostic marker for HF.

Systolic and diastolic time intervals measured from Doppler tissue imaging: normal values and Z-score tables, and effects of age, heart rate, and body surface area

The aim of this study was to develop normal values, including Z-score tables when appropriate, for systolic time (St) and diastolic time (Dt) intervals measured by Doppler tissue imaging (DTI) and to determine the effects of age, heart rate (HR), and body surface area on DTI-derived time intervals in children. We studied 593 children with normal echocardiogram results. Developmental factors ranged from age 1 day to 18 years, HR 46 to 182/min, and body surface area 0.08 to 2.80 m(2). A total of 7 DTI-derived time interval parameters were studied. Five time interval parameters were measured from DTI: isovolumic contraction time (IVCT), isovolumic relaxation time (IVRT), ejection time, St, and Dt. In addition, we calculated the Tei index (TX) and St/Dt. We sampled longitudinal directed DTI waves from 3 sites: mitral annulus, basal interventricular septum, and tricuspid annulus from an apical 4-chamber view. Parameters were measured in each case from a single echocardiogram during times of hemodynamic stability. By univariate analysis all 7 time intervals at each of the 3 sampling sites correlated with age, HR, and body surface area (P < .001-P < .003), except the mitral annulus TX (P = .1). The following results are all based on multivariate analysis. IVCT, IVRT, and TX correlated best with age at all 3 sites (P < .001). However, when we corrected for HR by dividing by square root(R)-R interval, both corrected IVCT and corrected IVRT became constants at all 3 sites. The change in TX with age was very small and not clinically significant. Therefore, for practical clinical purposes, corrected IVCT, corrected IVRT, and TX were constant at all 3 sites. Ejection time, St, Dt, and St/Dt correlated best with HR at all 3 sites (P < .001). Ejection time, St, and Dt all decreased at faster HRs, whereas St/Dt increased at faster HRs.

Comparison of early diastolic annular velocities measured at various sites of mitral annulus in detection of mild to moderate left ventricular diastolic dysfunction

Early diastolic mitral annular velocity (Em) as measured by pulsed-wave tissue Doppler echocardiography (PW-TDE) has been described as a relatively load independent index of left ventricular (LV) relaxation allowing more precise assessment of LV diastolic function. Nevertheless, substantial regional differences in Em are encountered. A systematic study comparing accuracy of the Em values measured at various annular sites in the assessment of LV diastolic function is still lacking. In this study we aimed to compare the discriminating power of Em velocities measured at the various sites of the mitral annulus in distinguishing between normal LV filling and mild to moderate LV diastolic dysfunction, and to determine the optimal cutoff values of Em at each mitral annular site. Em determined by PW-TDE was measured at four mitral annular sites in 69 patients with various heart diseases and compared to LV filling patterns obtained using standard flow Doppler indices. A comparison of receiver operating characteristic curves did not show significant differences for areas under the curve in favor of Em measured at any annular site (0.92 for septal, 0.96 for lateral, 0.96 for inferior and 0.93 for anterior site, 0.95 for the averaged value of Em from all annular sites, and 0.93 for the averaged value from septal and lateral sites, P not significant). The optimal cutoff values of Em were 0.08 m s(-1) for septal site (91% sensitivity, 89% specificity), 0.11 m s(-1) for lateral site, 0.09 m s(-1) for inferior site (both 91% sensitivity, 94% specificity), 0.10 m s(-1) for anterior annular site (88% sensitivity, 91% specificity), 0.11 m s(-1) for the averaged value of Em from all sites, and 0.11 m s(-1) for the averaged value from septal and lateral sites (both 97% sensitivity, 86% specificity). There are no differences in the accuracy of Em velocities obtained at various mitral annular sites regarding the detection of mild to moderate LV diastolic dysfunction. However, different cutoff values of Em at each mitral annular site must be considered for distinguishing between normal and mild to moderate LV diastolic dysfunction.

Longitudinal left ventricular contractile dysfunction after exercise in aortic stenosis

OBJECTIVE

To determine whether longitudinal left ventricular systolic function measured by Doppler tissue imaging (DTI) after exercise can identify early left ventricular dysfunction in asymptomatic patients with moderate-severe aortic stenosis.

DESIGN

Case-control study.

SETTING

Outpatient cardiology departments.

PATIENTS

20 patients with aortic stenosis, with or without equivocal symptoms, a peak aortic valve velocity > or =3 m/s, and left ventricular ejection fraction >50% and 15 aged-matched normal controls.

INTERVENTIONS

Echocardiogram performed at rest and immediately after treadmill exercise.

MAIN OUTCOME MEASURES

The peak systolic velocity of the lateral mitral annulus (S') by DTI at rest and immediately after exercise, exercise capacity, exercise systolic blood pressure and the plasma level of B-type natriuretic peptide (BNP).

RESULTS

For patients with aortic stenosis, mean (SD) aortic valve area was 0.95 (0.3) cm(2). At rest, S' was similar for patients with aortic stenosis and controls, respectively (8.5 (1.5) vs 9.1 (1.8) cm/s, p = 0.15). However, after exercise, S' (12.2 (3.2) vs 17 (2.8) cm/s, p<0.001) and the increase in S' between rest and exercise (4 (3) vs 7.9 (1.5) cm/s, p<0.001) were lower in patients with aortic stenosis. In patients with aortic stenosis, a smaller increase in S' after exercise was associated with lower exercise capacity (r = 0.5, p = 0.02), a smaller increase in exercise systolic blood pressure (r = 0.6, p = 0.005) and higher plasma level of BNP (r = 0.66, p = 0.002).

CONCLUSION

In asymptomatic patients with moderate-severe aortic stenosis a lower than normal increase in peak systolic mitral annular velocity after treadmill exercise is a marker of early left ventricular systolic dysfunction.

Are left ventricular diastolic function and diastolic asynchrony important determinants of response to cardiac resynchronization therapy?

Cardiac resynchronization therapy (CRT) has been shown to reduce symptoms and reverse left ventricular (LV) remodeling. It is not known, however, whether diastolic function will improve after CRT and diastolic asynchrony will predict LV reverse remodeling. Seventy-six patients (mean age 65 +/- 12 years, 74% men) who received CRT were studied at baseline and after 3 months. Diastolic function was assessed by transmitral Doppler and tissue Doppler imaging. LV systolic and diastolic asynchrony were assessed by the time to peak myocardial contraction (Ts) and early diastolic relaxation (Te) using the 6 basal, 6 mid-segmental model. There were 42 responders (55%) with LV reverse remodeling (defined as a reduction of LV end-systolic volume >or=15%). Parameters of systolic function were significantly improved only in the responders. For diastolic function, there were reductions of transmitral E velocity in the 2 groups, without any change in atrial velocity or the E/A ratio. Tissue Doppler imaging revealed that myocardial early diastolic velocity was unchanged in responders but was significantly worsened in nonresponders. The systolic asynchrony index (the SD of Ts of 12 LV segments) correlated significantly with LV reverse remodeling (r = -0.64, p <0.001) but not the diastolic asynchrony index (the SD of Te of 12 LV segments) (r = -0.10, p = NS). The systolic asynchrony index was the only independent predictor of reverse remodeling (beta = -0.99, 95% confidence interval -1.41 to -0.58, p <0.001). In conclusion, CRT improves systolic function and systolic asynchrony but has a neutral effect on diastolic function and diastolic asynchrony. LV reverse remodeling response is determined by the severity of prepacing systolic asynchrony but not diastolic asynchrony or the diastolic filling pattern.

Left Ventricular Systolic Longitudinal Function: Comparison Among Simple M-Mode, Pulsed, and M-Mode Color Tissue Doppler of Mitral Annulus in Healthy Individuals

BACKGROUND

M-mode determination of left ventricular (LV) atrioventricular plane displacement (AVPD) allows a simple assessment of LV longitudinal systolic function. Color tissue Doppler (TD) M-mode-derived AVPD and pulsed TD-derived systolic annular velocity are more sophisticated tools.

OBJECTIVE

We sought to compare these 3 techniques for the analysis of LV longitudinal systolic function.

METHODS

Standard M-mode AVPD, color TD M-mode AVPD, and systolic annular velocity were measured at 4 annular levels in 56 healthy individuals. The time to onset and the electromechanical interval were also determined using each technique.

RESULTS

Standard M-mode AVPD (r = 0.56, P < .0001) and color TD M-mode AVPD (r = .65, P < .0001) showed good correlation with systolic annular velocity. All 3 techniques revealed an inhomogeneous systolic shifting among different annular portions. Systolic intervals showed small discrepancies but high concordance between M-mode techniques and pulsed TD.

CONCLUSIONS

Standard M-mode imaging of the mitral annulus may be considered a reliable method for the assessment of LV longitudinal function.

Doppler tissue imaging in the assessment of atrioventricular conduction time: validation of a novel technique and comparison with electrophysiologic and pulsed wave Doppler-derived equivalents in an animal model

Accurate assessment of atrioventricular conduction time (AVCT) is crucial for early detection of evolving fetal heart block. Simultaneous pulsed wave Doppler (PD) interrogation of left ventricular inflow and outflow is mainly used to study fetal AVCT. Limitations of this modality include its dependency on loading conditions and merging early and late diastolic inflow waves at faster heart rate (HR). Sequential analysis of atrioventricular myocardial motion by Doppler tissue imaging (DTI) might be more useful in this regard. In 15 open-chest pigs, AVCT was measured by PD, DTI, and electrocardiogram at baseline HR and during incremental atrial pacing up to 200 beats/min. Electromechanical delay and pre-ejection period were assessed at baseline and maximal HR. DTI-derived AVCT correlated better with PR intervals and allowed measurements at faster HRs than did PD (P < .05). Pre-ejection period prolonged with faster HR (P < .001), unlike electromechanical delay. In conclusion, DTI allows more accurate measurement of AVCT over a wider HR range than does PD.

Reduced left ventricular function in hypoxemic newborn pigs: a strain Doppler echocardiographic study

Myocardial dysfunction, hypotension, and increased pulmonary artery pressure are induced by asphyxia in neonates. We sought to define left ventricular (LV) systolic function by measuring longitudinal and radial contraction by strain Doppler echocardiography (SDE) in hypoxemic newborn pigs. Hypoxemia was induced in 11 anesthetized and instrumented newborn pigs by ventilation with 8% O2 in nitrogen. When mean arterial blood pressure (BP) decreased to 15 mm Hg or arterial base excess reached -20 mmol/L or less, the pigs were reoxygenated and ventilated for 150 min. Echocardiography was performed at baseline and during hypoxemia and reoxygenation. Baseline measurements of myocardial peak systolic strain demonstrated normal longitudinal shortening and radial thickening. During hypoxemia, systolic longitudinal shortening in the mid-posterior and septal segments changed to systolic stretching. Peak strain in the mid-lateral and anterior segments decreased but without signs of paradox wall motion. Short-axis peak strain remained positive during hypoxemia, although the amplitude was reduced and delayed with respect to timing. In the newborn pig heart, we found a complex and heterogeneous systolic pattern with distinct regional differences during global hypoxemia. Rapid changes in LV function during hypoxemia and reoxygenation are assessable by SDE, and the results indicate that longitudinal systolic contraction is more vulnerable to hypoxemic changes than radial contraction. To explore the full picture of a global hypoxemic injury, both long- and short-axis functions have to be considered.

Echocardiography and patient selection for cardiac resynchronization therapy: A critical appraisal

Echocardiography has been the focus of growing interest for improving patient selection for cardiac resynchronization therapy in order to reduce the number of nonresponders. Various techniques have been described for assessing dyssynchrony, using standard echocardiography (pulsed-wave Doppler and M-mode echocardiography), tissue Doppler imaging, and other imaging modes such as three-dimensional echocardiography. This article provides an overview of the technical and practical aspects of these different techniques and discusses the current evidence for optimizing patient selection by echocardiography.

Usefulness of tissue Doppler imaging for demonstrating altered septal contraction sequence during dual-chamber pacing in obstructive hypertrophic cardiomyopathy

Dual-chamber pacing reduces left ventricular (LV) outflow obstruction in patients with obstructive hypertrophic cardiomyopathy (HC), the mechanism of which lies in pacing-induced paradoxic septal motion. This study was conducted to test the hypothesis that tissue Doppler imaging (TDI) could demonstrate changes in the septal contraction sequence during dual-chamber pacing in patients with HC. TDI was performed in 16 patients (5 women; mean age 63+/-11 years) who underwent dual-chamber pacing for 7.6+/-2.1 year. With and without pacing, the time to peak systolic myocardial velocity was measured from the basal, mid, and distal segments in the 4 different LV walls. Without pacing, there was almost no longitudinal segmental asynchrony. During pacing, however, marked longitudinal segmental asynchrony appeared, especially in the anteroseptal wall (from p=NS to p<0.01 by analysis of variance) and the ventricular septum (from p<0.05 to p<0.01), with the time to peak velocity extremely prolonged at the distal segments. This was associated with a modest but significant decrease in the LV pressure gradient (from 20+/-8 to 14+/-7 mm Hg, p<0.01). In patients with obstructive HC, altered septal contraction sequence accounts for the reduced LV outflow obstruction during dual-chamber pacing, which was clearly demonstrated by TDI.

Prognostic value of systolic mitral annular velocity measured with Doppler tissue imaging in patients with chronic heart failure caused by left ventricular systolic dysfunction

OBJECTIVE

To assess the prognostic value of various conventional and novel echocardiographic indices in patients with chronic heart failure (CHF) caused by left ventricular (LV) systolic dysfunction.

METHODS

185 patients with a mean (SD) age of 67 (11) years with CHF and LV ejection fraction < 45% despite optimal pharmacological treatment were prospectively enrolled. The patients underwent two dimensional echocardiography with tissue harmonic imaging to assess global LV systolic function and obtain volumetric data. Transmitral flow was assessed with conventional pulse wave Doppler. Systolic (Sm), early, and late diastolic mitral annular velocities were measured with the use of colour coded Doppler tissue imaging.

RESULTS

During a median follow up of 32 months (range 24-38 months in survivors), 34 patients died and one underwent heart transplantation. Sm velocity (hazard ratio (HR) 0.648, 95% confidence interval (CI) 0.463 to 0.907, p = 0.011), diastolic arterial pressure (HR 0.965, 95% CI 0.938 to 0.993, p = 0.015), serum creatinine (HR 1.006, 95% CI 1.001 to 1.011, p = 0.023), LV ejection fraction (HR 0.945, 95% CI 0.899 to 0.992, p = 0.024), age (HR 1.035, 95% CI 1.000 to 1.071, p = 0.052), LV end systolic volume index (HR 1.009, 95% CI 0.999 to 1.019, p = 0.067), and restrictive pattern of transmitral flow (HR 0.543, 95% CI 0.278 to 1.061, p = 0.074) predicted the outcome of death or transplantation on univariate analysis. On multivariate analysis, only Sm velocity (HR 0.648, 95% CI 0.460 to 0.912, p = 0.013) and diastolic arterial pressure (HR 0.966, 95% CI 0.938 to 0.994, p = 0.016) emerged as independent predictors of outcome.

CONCLUSIONS

In patients with CHF and LV systolic dysfunction despite optimal pharmacological treatment, the strongest independent echocardiographic predictor of prognosis was Sm velocity measured with quantitative colour coded Doppler tissue imaging.

Left ventricular diastolic dysfunction is accompanied by increased aortic stiffness in the early stages of essential hypertension: a TDI approach

OBJECTIVE

To investigate the inter-relationship between aortic stiffness and left ventricular (LV) diastolic function in subjects with newly diagnosed uncomplicated essential hypertension.

METHODS

We studied 106 consecutive newly diagnosed subjects (aged 51 years, 80 males) with stage I-II essential hypertension, and 50 normotensives matched for age, sex and body mass index. LV diastolic function was estimated by pulsed tissue Doppler imaging (TDI) echocardiography, averaging diastolic mitral annular velocity measurements (Emav, Amav, Emav/Amav ratio) from four separate sites (basal septal, lateral, anterior, and inferior LV wall). Moreover, aortic stiffness was evaluated by non-invasive carotid-femoral pulse wave velocity (c-f PWV) measurement.

RESULTS

Hypertensives compared with normotensives exhibited greater LV mass index and Amav (110 versus 95 g/m and 10 versus 8.8 cm/s, respectively, P < 0.001 for both cases), and greater c-f PWV (8.47 versus 7.48 m/s, P < 0.03), as well as lower Emav and Emav/Amav values, (8.4 versus 10 cm/s and 0.82 versus 1.15, respectively, P < 0.001 for both cases). In the group of hypertensives, a univariate analysis revealed that c-f PWV was negatively associated with Emav (r = -0.305, P = 0.005), as well as with Emav/Amav ratio (r = -0.437, P < 0.001). Moreover, a multivariate analysis showed that the TDI-derived Emav/Amav ratio was significantly associated with age (P = 0.001), relative wall thickness (P = 0.006) and c-f PWV (P = 0.03), while the conventional Doppler-derived E/A ratio was significantly associated only with age (P = 0.001).

CONCLUSIONS

TDI-detected LV diastolic dysfunction is accompanied by increased aortic stiffness in newly diagnosed essential hypertension, suggesting that there may be a common pathophysiological pathway linking these two entities.

Impact of cardiac growth on Doppler tissue imaging velocities: a study in healthy children

BACKGROUND

Doppler tissue imaging (DTI) is a useful modality to quantitatively assess regional myocardial function. Studies attempting to establish reference values for DTI velocities in healthy children have been limited by small sample sizes and limited age distribution. In addition, the clinical effect of cardiac growth and other demographic and echocardiographic parameters on DTI velocities during childhood has not been adequately evaluated.

METHODS

Pulsed wave DTI velocities were obtained in 325 healthy children at the lateral mitral annulus, interventricular septum, and lateral tricuspid annulus during early diastole, late diastole, and ventricular systole and were compared with demographic and echocardiographic study variables.

RESULTS

In healthy children, parameters of cardiac growth, most notably left ventricular end-diastolic dimension, have the most significant correlation with the majority of DTI velocities. Age was also significantly correlated with most DTI velocities whereas sex, heart rate, and other echocardiographic parameters demonstrated minimal or no correlation.

CONCLUSIONS

This study establishes reference values for DTI velocities and demonstrates the important clinical effects of cardiac growth and age on DTI velocities in neonates and children.

Comparison of Efficacy of Reverse Remodeling and Clinical Improvement for Relatively Narrow and Wide QRS Complexes After Cardiac Resynchronization Therapy for Heart Failure

INTRODUCTION

Cardiac resynchronization therapy (CRT) has been shown to reverse left ventricular (LV) remodeling and improve symptoms in heart failure patients with wide QRS complexes; however, its role in patients with mildly prolonged QRS complexes is unclear. This study investigated if CRT benefited patients with mildly prolonged QRS complexes >120 to 150 ms and explored if the severity of systolic asynchrony determined such a response.

METHODS AND RESULTS

Fifty-eight patients (age 66 +/- 11 years, 66% male) who had undergone CRT were studied prospectively. Of these patients, 27 had QRS duration between 120 and 150 ms (group A), and 31 had QRS duration >150 ms (group B). Tissue Doppler echocardiography and clinical assessment were performed at baseline and 3 months after CRT. Both groups had significant reduction of LV volume and increased ejection fraction, +dP/dt, and sphericity index (all P < 0.05). These improvements were greater in group B and were explained by the higher prevalence of systolic intraventricular asynchrony. Significant reverse remodeling (reduction of LV end-systolic volume >15%) was evident in 46% of group A patients and 68% of group B patients. Improvement in clinical endpoints was observed in both groups (all P < 0.01), although the changes in metabolic equivalent and New York Heart Association functional class were greater in group B. In both groups, systolic asynchrony index (TS-SD) was the most important predictor of reverse remodeling (r =-0.78, P < 0.001) and was the only independent predictor in the multivariate model (beta=-1.80, confidence interval =-2.18 to -1.42, P < 0.001); QRS duration was not. A predefined TS-SD value >32.6 ms had a sensitivity of 94% and specificity of 83% to predict reverse remodeling. Improvement of intraventricular asynchrony after CRT was evident only in responders (P = 0.01).

CONCLUSION

Improvement of LV remodeling and clinical status is evident after CRT in heart failure patients with QRS duration >120 to 150 ms. These responders are closely predicted by the severity of prepacing intraventricular asynchrony but not QRS duration.

Tissue Doppler echocardiography - a case of right tool, wrong use

Background

The developments in echocardiography or ultrasound cardiography (UCG) have improved our clinical capabilities. However, advanced hardware and software capabilities have resulted in UCG facilities of dubious clinical benefits. Is tissue Doppler echocardiography (TDE) is one such example?

Presentation of the hypothesis

TDE has been touted as advancement in the field of echocardiography. The striking play of colors, impressive waveforms and the seemingly accurate velocity values could be deceptive. TDE is a clear case of inappropriate use of technology.

Testing the hypothesis

To understand this, a comparison between flow Doppler and tissue Doppler is made. To make clinically meaningful velocity measurements with Doppler, we need prior knowledge of the line of motion. This is possible in blood flow but impossible in the complex myocardial motion. The qualitative comparison makes it evident that Doppler is best suited for flow studies.

Implications of the hypothesis

As of now TDE is going backwards using an indirect method when direct methods are better. The work on TDE at present is only debatable 'research and publication' material and do not translate into tangible clinical benefits. There are several advances like curved M-mode, strain rate imaging and tissue tracking in TDE. However these have been disappointing. This is due to the basic flaw in the application of the principles of Doppler. Doppler is best suited for flow studies and applying it to tissue motion is illogical. All data obtained by TDE is scientifically incorrect. This makes all the published papers on the subject flawed. Making diagnostic decisions based on this faulty application of technology would be unacceptable to the scientific cardiologist.