Echocardiographic Doppler evaluation of left ventricular diastolic function. Physics and physiology

Comparison of cardiac function between single left ventricle and tricuspid atresia: assessment using echocardiography combined with computational fluid dynamics

Patients with single left ventricle (SLV) and tricuspid atresia (TA) have impaired systolic and diastolic function. However, there are few comparative studies among patients with SLV, TA and children without heart disease. The current study includes 15 children in each group. The parameters measured by two-dimensional echocardiography, three-dimensional speckle tracking echocardiography (3DSTE), and vortexes calculated by computational fluid dynamics were compared among these three groups. Twist is best correlated with ejection fraction measured by 3DSTE. Twist, torsion, apical rotation, average radial strain, peak velocity of systolic wave in left lateral wall by tissue Doppler imaging (sL), and myocardial performance index are better in the TA group than those in the SLV group. sL by tissue Doppler imaging in the TA group are even higher than those in the Control group. In patients with SLV, blood flow spreads out in a fan-shaped manner and forms two small vortices. In the TA group, the main vortex is similar to the one in a normal LV chamber, but smaller. The vortex rings during diastolic phase are incomplete in the SLV and TA groups. In summary, patients with SLV or TA have impaired systolic and diastolic function. Patients with SLV had poorer cardiac function than those with TA due to less compensation and more disordered streamline. Twist may be good indicator for LV function.

Imaging in Heart Failure with Preserved Ejection Fraction: A Multimodality Imaging Point of View

Heart failure with preserved ejection fraction (HFpEF) is an important global health problem. Despite increased prevalence due to improved diagnostic options, limited improvement has been achieved in cardiac outcomes. HFpEF is an extremely complex syndrome and multimodality imaging is important for diagnosis, identifying its different phenotypes and determining prognosis. Evaluation of left ventricular filling pressures using echocardiographic diastolic function parameters is the first step of imaging in clinical practice. The role of echocardiography is becoming more popular and with the recent developments in deformation imaging, cardiac MRI is extremely important as it can provide tissue characterisation, identify fibrosis and optimal volume measurements of cardiac chambers. Nuclear imaging methods can also be used in the diagnosis of specific diseases, such as cardiac amyloidosis.

Cardiorespiratory effects of different intraabdominal pressures in sheep: An experimental study

Increased intraabdominal pressure (IAP) during laparoscopy can reduce venous return, but changes in respiratory system mechanics and their effect in left cardiac function are not well documented. This study evaluated the effects of different IAPs on respiratory mechanics and cardiac function in 10 healthy nonpregnant adult Santa Ines ewes randomly submitted to a crossover study using different IAPs: 0 mm Hg (G1), 10 mm Hg (G2), 12 mmHg (G3), and 15 mmHg (G4). Animals were anesthetized and mechanically ventilated (VT  = 15 ml/kg; positive end-expiratory pressure = 3 cmH2 O; FiO2  = 1.0). Pneumoperitoneum was induced by Hasson's trocar cannula. Variables were measured at INITIAL (IAP, 0 mmHg) and FINAL time points for each IAP after 1 h. At FINAL, driving airway pressure (ΔP,RS ), and percentage fraction of dead space (Vd/Vt) were higher in G3 and G4 than G1 (p = 0.002, difference in means [MD] 4.60, 95% CI: 7.91-1.28, and p < 0.001, MD 5.4, 95% CI: 8.7-2.0; p = 0.016, MD -9.5, 95% CI: -17.9 to -1.2; and p = 0.027, MD -8.7, 95% CI: -17.1 to -0.4). The ejection fraction and fractional shortening were lower in G3 (p = 0.039, MD -11.38, 95% CI: -0.07--22.68; p = 0.015, MD -13.05, 95% CI: -1.74--24.36) and G4 (p = 0.039, MD -9.94, 95% CI: -0.07 to -19.80; p = 0.015, MD -11.43, 95%CI: -1.57 to -21.30, respectively) than G2. In G3, the maximum pulmonary flow velocity correlated negatively with ΔP,RS (r = -0.740; p = 0.018), and Vd/Vt correlated positively with ΔP,RS (r = 0.738, p = 0.046). At IAP of 12 and 15 mm Hg impaired respiratory system mechanics, reduced left cardiac function and no change in maximum pulmonary artery flow velocity were detected. Therefore, respiratory mechanics should be monitored as an interplay to reduce left cardiac function.

The long-term prognostic value of E/e' in patients with ST segment elevation myocardial infarction

Objectives

This study aimed to evaluate the long-term prognostic value of E/e’ ratio in patients with ST-segment elevation myocardial infarction (STEMI).

Methods

We retrospectively assessed 314 patients who underwent primary coronary interventions between January 2010 and December 2015. The included patients were classified into two groups according to the E/e’ ratios: E/e’<15 (n = 245) and E/e’≥15 (n = 69). We investigated the incidence of major adverse cardiac events (MACEs) from the event to the final follow-up period of at least three years.

Results

A total of 55 cases of MACEs occurred during the follow-up. The E/e’≥15 group showed a significantly higher rate of MACEs than the E/e’<15 group (34.8% vs. 12.7%, p < 0.001). Among the MACE, the percentage of cardiac deaths (17.4% vs. 0.4%, p < 0.001) was higher in the E/e’≥15 group than in the E/e’<15 group. In the multivariable model, E/e’≥15 was demonstrated as the strongest prognostic factor for MACEs (hazard ratio [HR], 2.597; 95% confidence interval [CI], 1.294–5.211; p = 0.007) and cardiac death (HR, 27.537; 95% CI, 3.287–230.689; p = 0.002), while left ventricular ejection fraction (LVEF) was not. Neither the discrepancy of systolic nor diastolic function between initial and follow-up echocardiography affected the overall prevalence of MACEs. A disparity was observed between the two groups, with a significant increase in the rate of MACEs in the E/e’≥15 group (log-rank test, p < 0.001).

Conclusion

The baseline E/e’≥15 in patients with STEMI after successful reperfusion is the strongest predictor of poor long-term clinical outcomes among those analyzed.

Left Ventricular Diastolic Dysfunction Among Youth with Obesity and History of Elevated Blood Pressure

OBJECTIVE

To assess prevalence of and factors associated with left ventricular diastolic dysfunction (LVDD) in youth with obesity and elevated blood pressure (BP).

STUDY DESIGN

This was a cross-sectional analysis of baseline and follow-up visits of 83 youth, 5-21 years, evaluated for overweight/obesity and elevated BP in a multidisciplinary clinic. LVDD was defined according to established adult criteria (LVDD_adult; E/A < 1, E/e' > 14, or e'/a' < 0.8) and pediatric criteria (LVDD_peds; E/A <10th percentile, E/e' >99th percentile, or e'/a' <1st percentile) based on data from 103 age-sex matched healthy controls. Baseline factors associated with LVDD_peds were examined using Wilcoxon rank sum and χ² tests. Multiple logistic regression analyses using generalized estimating equations to account for repeated measures evaluated the associations of adiposity and BP with LVDD_peds.

RESULTS

The prevalence of LVDD ranged from 1.2% to 2.7% when we used adult criteria and 19% to 28% when we used pediatric criteria. Those with LVDD_peds were older, predominantly male, and non-African American and had greater weight, BP, BP medication use, and non-high-density lipoprotein cholesterol than those without LVDD_peds. Diastolic BP z score was associated with LVDD_peds by E/A (OR 1.95, 95% CI 1.15-3.32, P = .014) after we adjusted for age, sex, race, BP medications, and body mass index z score.

CONCLUSIONS

LVDD was present in a substantial proportion of youth with overweight/obesity and elevated BP using pediatric criteria. Those with LVDD_peds had significantly greater measures of adiposity and BP compared with those without LVDD_peds, and diastolic BP z score was an independent predictor of LVDD_peds by E/A. These data emphasize the importance of prevention and treatment of cardiovascular disease risk factors in childhood.

Assessment of cardiac diastolic function in infants of diabetic mothers using tissue Doppler echocardiography

Background

Limited number of studies evaluated cardiac diastolic function in infants of diabetic mothers using tissue Doppler imaging. The aim of this study was to evaluate diastolic parameters in full-term infants of diabetic mothers compared to healthy full-term neonates using both conventional echocardiography and tissue Doppler imaging. This study is a comparative study. Fifty consecutive infants of diabetic mothers (cases) in the first 3 days of life: 25 neonates with poor maternal glycemic control (Hemoglobin A1c > 7.5 g/dl) and 25 neonates with good maternal glycemic control (Hemoglobin A1c ≤ 7.5 g/dl). Thirty healthy full-term infants of non-diabetic mothers with age and sex matching were included as controls. The studied groups were assessed by conventional pulsed wave Doppler and tissue Doppler imaging.

Results

Among pulsed wave Doppler parameters, cases had lower values than controls as regards mitral E velocity, mitral E/A ratio, tricuspid E velocity, and tricuspid E/A ratio, while neonates with poor maternal glycemic control had lower values than those with good maternal glycemic control as regards mitral E/A ratio, tricuspid E velocity, and tricuspid E/A ratio as well as higher mitral A velocity (denoting more diastolic dysfunction). Similarly, among tissue Doppler parameters, cases had lower values than controls as regards septal E' velocity, E'/A' ratio, left ventricular E' velocity, E'/A' ratio, and right ventricular E' velocity as well as higher septal A' velocity, left ventricular A' velocity, and right ventricular A' velocity, while neonates with poor maternal glycemic control had lower values than those with good maternal glycemic control as regards septal E' velocity, E'/A' ratio, left ventricular E' velocity, E'/A' ratio, and right ventricular E' velocity, as well as higher left ventricular A' velocity (denoting more diastolic dysfunction). Tissue Doppler was able to detect higher number of neonates with left ventricular diastolic dysfunction than conventional pulsed wave Doppler.

Conclusions

Tissue Doppler imaging was found to be able to detect diastolic dysfunction early in infants of diabetic mothers specifically as regards the left ventricle. Tissue Doppler imaging should be considered an integral part of cardiac function assessment in infants of diabetic mothers.

E/e' in relation to outcomes in ST-elevation myocardial infarction

BACKGROUND

Myocardial infarction (MI) is a high-risk condition especially when filling pressure is raised, and earlier reports have suggested that E/e' is associated with poor outcome. However, whether E/e' predicts risk better than LVEF, which is the current standard of practice, is not known. We investigated this question in the largest and most rigorous study of MI patients so far.

METHODS AND RESULTS

We studied 660 patients with ST-elevation MI (STEMI) treated with primary percutaneous coronary intervention and related E/e' to short-term mortality (in-hospital death), as well as long-term events at 2 years comprising (a) a composite of MI, stroke, heart failure, and death, and (b) death alone. Short-term models were adjusted for age, sex, and LVEF. Long-term models were adjusted for age, sex, diabetes, revascularization procedure, history of MI, hypertension, renal function, drugs on discharge, and LVEF. Elevated E/e'> 15 indicated higher risk of short-term events (n = 19:7.0% (95% confidence interval 3.4-10.8%) vs. 1.0% (0.3 - 2.3%); adjusted odds ratio 3.7 (1.3-10.5)). While elevated E/e' was also associated with long-term outcomes (n = 103 composite events: 15.9% (11.9% - 21.4%) vs 6.8% (5.2% - 8.7%), P < .001; n = 38 death events: 6.0% (3.9% - 9.5%) vs 2.0% (1.3% - 3.2%), P = .001), E/e' was rendered nonsignificant for long-term outcomes by multivariable adjustment (p = ns for both). LVEF, on the contrary, was a highly significant predictor in the adjusted long-term model.

CONCLUSION

E/e' is associated with poor outcome in STEMI, but LVEF is a stronger predictor of long-term risk.

Alternative diastolic function models of ventricular longitudinal filling velocity are mathematically identical

The spatiotemporal features of normal in vivo cardiac motion are well established. Longitudinal velocity has become a focus of diastolic function (DF) characterization, particularly the tissue Doppler e'-wave, manifesting in early diastole when the left ventricle (LV) is a mechanical suction pump (dP/dV < 0). To characterize DF and elucidate mechanistic features, several models have been proposed and have been previously compared algebraically, numerically, and in their ability to fit physiological velocity data. We analyze two previously noncompared models of early rapid-filling lengthening velocity (Doppler e'-wave): parametrized diastolic filling (PDF) and force balance model (FBM). Our initial numerical experiments sampled FBM-generated e'(t) contours as input to determine PDF model predicted fit. The resulting exact numerical agreement [standard error of regression (SER) = 9.06 × 10^-16] was not anticipated. Therefore, we analyzed all published FBM-generated e'(t) contours and observed identical agreement. We re-expressed FBM's algebraic expressions for e'(t) and observed for the first time that model-based predictions for lengthening velocity by the FBM and the PDF model are mathematically identical: e'(t) = γe^-αtsinh(βt), thereby providing exact algebraic relations between the three PDF parameters and the six FBM parameters. Previous pioneering experiments have independently established the unique determinants of e'(t) to be LV relaxation, restoring forces (stiffness), and load. In light of the exact intermodel agreement, we conclude that the three PDF parameters, relaxation, stiffness (restoring forces), and load, are unique determinants of DF and e'(t). Thus, we show that only the PDF formalism can compute the three unique, independent, physiological determinants of long-axis LV myocardial velocity from e'(t).NEW & NOTEWORTHY We show that two separate, independently derived physiological (kinematic) models predict mathematically identical expressions for LV-lengthening velocity (Doppler e'-wave), indicating that damped harmonic oscillatory motion is a physiologically accurate model of diastolic function. Although both models predict the same "overdamped" velocity contour, only one model solves the "inverse problem" and generates unique, lumped parameters of relaxation, stiffness (restoring force), and load from the e'-wave.

High frame rate cardiac cine MRI for the evaluation of diastolic function and its direct correlation with echocardiography

BACKGROUND

Breath-hold cine MR is the method of choice for evaluating left ventricular (LV) systolic function; however, the evaluation of diastolic function remains in the domain of high frame rate echocardiography. Thus, a cine MR technique for simultaneously evaluating LV systolic and diastolic function would be clinically valuable.

PURPOSE

To test the feasibility of extracting indices that characterize LV diastolic function from high frame rate cine MR.

STUDY TYPE

Single center, prospective.

POPULATION

Asymptomatic volunteers (N = 24; age 45.8 ± 12.3 years).

FIELD STRENGTH/SEQUENCE

High frame rate (70 fps) cine MR and phase-contrast MR during free breathing were acquired at 1.5T.

ASSESSMENT

The following MR-based LV filling metrics were extracted from LV volume changes during the cardiac cycle: 1) the volume-rate ratio, R_EFP /R_LFP (ratio of the peak LV filling rate during the early filling period [EFP] to that during the late filling period [LFP]); and 2) the volume ratio, V_EFP /V_LFP (the ratio of cumulative LV volume change between the EFP and LFP). These metrics were then compared with traditional transmitral blood flow-based MR and echocardiographic indices. The effect of temporal resolution on these metrics was also evaluated.

STATISTICAL TESTS

Bland-Altman and linear regression analyses were used to evaluate the performance of the proposed metrics against traditional indices of diastolic function.

RESULTS

The R_EFP /R_LFP and V_EFP /V_LFP correlated well with E/A_Q-flow (r ² = 0.66 and 0.54, respectively) and E/A_echo (r ² = 0.58 and 0.49, respectively). Systolic indices remained robust (<3% error) for frame rates ≥20 fps. Although the proposed V_EFP /V_LFP was robust (<5% error) up to 25 fps, the proposed volume-rate diastolic function metrics were less reliable (>8% error) for frame rates below 35 fps.

DATA CONCLUSION

In asymptomatic volunteers, cardiac cine MR images acquired at frame rates >35 fps can be used to extract LV diastolic function indices from the temporal changes in LV volume.

LEVEL OF EVIDENCE

1 Technical Efficacy Stage: 1 J. Magn. Reson. Imaging 2019;50:1571-1582.

Impaired left ventricular diastolic function in T2DM patients is closely related to glycemic control

BACKGROUND

Left ventricular (LV) diastolic dysfunction commonly is observed in individuals with type 2 diabetes mellitus (T2DM). We employed transthoracic echocardiography (TTE) and cardiac magnetic resonance imaging (CMRI) to investigate the hypothesis that LV diastolic dysfunction in T2DM is associated with poor glycemic control.

METHODS

Forty subjects, 21 with normal glucose tolerance (NGT) and 19 with T2DM, were studied with CMRI and TTE to assess LV function. Early-to-late transmitral flow ratio (E/A) and deceleration time (DecT) were assessed with both modalities. Normalized (to body surface area) end-diastolic volume (EDV/BSA) and normalized peak LV filling rate (pLVFR/BSA) were assessed with CMRI. Early transmitral flow velocity to septal velocity (E/e') and isovolumetric relaxation time (IVRT) were measured using TTE. Dimensional parameters were normalized to body surface area (BSA).

RESULTS

CMRI measurements demonstrated impaired E/A (1.13 ± 0.34 vs 1.62 ± 0.42, P < .001), increased DecT (174 ± 46 ms vs 146 ± 15, P = .005), as well as lower EDV/BSA (63 ± 10 vs 72 ± 9 mL/m2, P < .01) and pLVFR/BSA (189 ± 46 vs 221 ± 48 mL s-1 m-2, P < .05) in T2DM subjects. TTE measurements revealed lower E/A (1.1 ± 0.4 vs 1.4 ± 0.2, P < .001) and E/e' (6.8 ± 1.5 vs 8.7 ± 2.0, P < .0001) with higher DecT (203 ± 22 ms vs 179 ± 18, P < .001) and IVRT (106 ± 14 ms vs 92 ± 10, P < .001) in T2DM. Multiple parameters of LV function: E/ACMRI (r = -.50, P = .001), E/ATTE (r = -.46, P < .005), pLVFR/BSA (r = -.35, P < .05), E/e' (r = -.46, P < .005), EDV/BSACMRI (r = -.51, P < .0001), EDV/BSATTE (r = -.42, P < .01) were negatively correlated with HbA1c. All but E/e' also were inversely correlated with fasting plasma glucose (FPG).

CONCLUSIONS

Impaired LV diastolic function (DF) was found in T2DM subjects with both CMRI and TTE, and multiple LVDF parameters correlated negatively with HbA1c and FPG. These results indicate that impaired LVDF is inversely linked to glycemic control in T2DM patients.

A Test in Context: E/A and E/e' to Assess Diastolic Dysfunction and LV Filling Pressure

Diastolic dysfunction represents a combination of impaired left ventricular (LV) relaxation, restoration forces, myocyte lengthening load, and atrial function, culminating in increased LV filling pressures. Current Doppler echocardiography guidelines recommend using early to late diastolic transmitral flow velocity (E/A) to assess diastolic function, and E to early diastolic mitral annular tissue velocity (E/e') to estimate LV filling pressures. Although both parameters have important diagnostic and prognostic implications, they should be interpreted in the context of a patient's age and the rest of the echocardiogram to describe diastolic function and guide patient management. This review discusses: 1) the physiological basis for the E/A and E/e' ratios; 2) their roles in diagnosing diastolic dysfunction; 3) prognostic implications of abnormalities in E/A and E/e'; 4) special scenarios of the E/A and E/e' ratios that are either useful or challenging when evaluating diastolic function clinically; and 5) their usefulness in guiding therapeutic decision making.

Studying diastology with speckle tracking echocardiography: The essentials

Diastolic dysfunction is common in cardiac disease and an important finding independent of systolic function as it contributes to the signs and symptoms of heart failure. Tissue Doppler mitral early diastolic velocity (Ea) combined with peak transmitral early diastolic velocity (E) to obtain E/Ea ratio provides an estimate of the left ventricular (LV) filling pressure. However, E/Ea has a significant gray zone and less reliable in patients with preserved ejection fraction (>50%). Two-dimensional echocardiographic speckle tracking measure myocardial strain and strain rate (Sr) avoiding the Doppler-associated angulation errors and tethering artifacts. Global myocardial peak diastolic strain (Ds) and diastolic Sr (DSr) at the time of E and isovolumic relaxation combined with E (E/Ds and E/10 DSr) have been recently proposed as novel indices to determine LV filling pressure. The present article elucidates the methodology of studying diastology with strain echocardiography along with the advantages and limitations of the novel technique in light of the available literature.

Prevalence of arterial stiffness and the risk of myocardial diastolic dysfunction in women

The present study reports markers of vascular function among a general female population and shows that left ventricular diastolic dysfunction (LVDD) is significantly associated with pathological PWV (⩾9.7 m/s), a waist circumference >80 cm and age.

The present study determines the prevalence of vascular dysfunction and arterial stiffness (ASt) in a female urban population by measuring the brachial augmentation index (AIx) and aortic pulse wave velocity (PWV). The study tests the hypothesis that the measurement of AIx and PWV is useful in addition to that of traditional cardiovascular risk factors when assessing the risk for left ventricular diastolic dysfunction (LVDD). This cross-sectional study recruited 965 women aged 25–75 years from 12 districts of Berlin. The ASt indices, brachial AIx, aortic PWV and the central blood pressure were measured by an oscillometric method. A randomly selected subgroup (n=343) was examined by echocardiography. Trans-mitral inflow E/A ratio and diastolic mitral annulus velocity (é) were assessed. Questionnaires, medical history and blood sampling were used for the evaluation of individual risk factors. Normal vascular function was found in 55% of the women included. The prevalence of women with pathological AIx only (AIx ⩾ −10%, PWV normal) was 21.5%, whereas 17.9% were affected by increased AIx and PWV (AIx ⩾ −10%, PWV ⩾9.7 m/s), and 6% with only pathological PWV values. The prevalence of LVDD was 31.7%. LVDD was significantly associated with pathological PWV ⩾ 9.7 m/s [OR: 1.27, 95%CI: 1.02–1.57], age [OR: 4.17, 95%CI: 2.87–6.07] and a waist circumference >80 cm [OR: 3.61, 95%CI: 1.85–7.04] in multiple regression analysis. The high prevalence of markers for vascular dysfunction and ASt in a general female population and their importance as a mediator of diastolic dysfunction should encourage implementation of aortic PWV measurement to improve cardiovascular-risk assessment in particular to identify subclinical myocardial diastolic dysfunction.

Effect of Left Bundle Branch Block on Systolic and Diastolic Function of Left Ventricle in Heart Failure

This study was designed to examine the effect of left bundle branch block (LBBB) on systolic and diastolic function of the left ventricle (LV) in patients with heart failure and in normal subjects. Thirty-six patients with heart failure and LBBB (group I), 36 patients with heart failure with normal conduction (group II), and 41 subjects with isolated LBBB (group III) were compared. Coronary angiography was performed and LV end diastolic pressure was calculated. Echocardiography was performed on all patients. LV ejection fraction and mean rate of circum ferential shortening were calculated. The following Doppler parameters were evaluated: peak rapid filling velocity (E wave), peak atrial filling velocity (A wave), E- and A-wave integrals, E- wave acceleration time and deceleration time (EDT) and rates (EAR and EDR), the E/A ratio and its integral, and diastolic flow time (DT). The ejection time, isovolumetric relaxation time (IRT), and preejection period were measured using the aortic and mitral flow. LV end diastolic pressure was calculated as 28 ±4 mm Hg, 22 ±5 mm Hg, and 15 ±3 mm Hg in groups I, II, and III, respectively. Although the systolic function parameters in group III patients were different, the diastolic function parameters of group II were found to be quite similar to those of group III patients. Comparison of group I patients with group II patients showed that there was a similarity between LV systolic function parameters while the diastolic function parameters were different (E/A, p = 0.004; EAR, p<0.001; EDR, p<0.001; EDT, p<0.001; IRT, p = 0.024; DT, p=0.03). In conclusion, this study evaluating the effects of LBBB in normal subjects (isolated LBBB) and patients with heart failure showed that LBBB causes diastolic function impairment in normal subjects similar to those of patients with heart failure, and also increases impairment of diastolic function in patients with heart failure.

Diastolic Function

Information about left ventricular function was traditionally provided primarily with measures of systolic function. Including the assessment of diastolic function has become an integral part of the evaluation of left ventricular function. Echocardiographic parameters of structure and Doppler provide information on each portion of the diastolic phases. These diastolic phases indicate change as impairment in diastolic function becomes more severe. This review of diastolic function provides the background as well as the techniques for clinical assessment of diastolic function in adult transthoracic echocardiography.

Long-Term Effects of In Utero Antiretroviral Exposure: Systolic and Diastolic Function in HIV-Exposed Uninfected Youth

The aim of this study was to evaluate the association of in utero exposure to highly active antiretroviral therapy (HAART) with left ventricular (LV) function and structure in HIV-exposed uninfected (HEU) children. A prospective, multisite cohort study in HEU children was conducted by the Pediatric HIV/AIDS Cohort Study (PHACS). Echocardiographic measures of LV systolic and diastolic function and cardiac structure were obtained from HEU subjects aged ≥6 years enrolled in the PHACS Surveillance Monitoring of ART Toxicities study. Echocardiographic Z-scores were calculated using normative data from an established reference cohort. We used adjusted linear regression models to compare Z-scores for echocardiographic measures from HEU children exposed in utero to HAART with those exposed to non-HAART, adjusting for demographic and maternal health characteristics. One hundred seventy-four HEU subjects with echocardiograms and maternal ARV information were included (mean age 10.9 years; 48% male, 56% black non-Hispanic). Among 156 HEU youth with any ARV exposure, we observed no differences in Z-scores for LV systolic function measures between youth exposed in utero to HAART (39%) and HAART-unexposed youth in either unadjusted or adjusted models. In adjusted models, those exposed to HAART had significantly lower mitral late diastolic inflow velocities (adjusted mean Z-score = 0.00 vs. 0.52, p = .04) and significantly higher adjusted mean LV mass-to-volume ratio Z-scores (adjusted mean Z-score = 0.47 vs. 0.11, p = .03) than HAART-unexposed youth. Uninfected children with perinatal exposure to HAART had no difference in LV systolic function. However, small but significant differences in LV diastolic function and cardiac structure were observed, suggesting that continued monitoring for cardiac outcomes is warranted in this population.

Acceleration rate of mitral inflow E wave: a novel transmitral doppler index for assessing diastolic function

Background

We performed comprehensive transmitral and pulmonary venous Doppler echocardiographic studies to devise a novel index of diastolic function. This is the first study to assess the utility of the acceleration rate (AR) of the E wave of mitral inflow as a primary diagnostic modality for assessing diastolic function.

Methods

Study group consisted of 84 patients (53 + 11 years) with left ventricle (LV) diastolic dysfunction and 34 healthy people (35 ± 9 years) as control group, who were referred for clinically indicated two-dimensional transthoracic echocardiogram (TTE) during 2012 and 2013 to Imam Hospital. Normal controls were defined as patients without clinical evidence of cardiac disease and had normal TTE. LV diastolic function was determined according to standardized protocol of American Society of Echocardiography (ASE). As our new parameter, AR of E wave of mitral inflow was also measured in all patients. It was represented by the slope of the line between onset of E wave and peak of it. Correlation between AR of E wave and LV diastolic function grade was measured using the Spearman correlation coefficient. Receiver operating characteristic (ROC) curve was used to determine the sensitivity and specificity of AR of E wave in diagnosing LV diastolic dysfunction in randomly selected two-thirds of population then its derived cutoff was evaluated in rest of the population. The institutional review board of the hospital approved the study protocol. All participants gave written informed consent. This investigation was in accordance with the Declaration of Helsinki.

Results

The mean value of AR was 1010 ± 420 cm/s² in patients whereas the mean value for the normal controls was 701 ± 210 cm/s². There was a strong and graded relation between AR of E wave of mitral inflow and LV diastolic function grade (Spearman P ≤0.0001, r_s =0.69). ROC curve analysis revealed that AR of E wave of mitral inflow =750 cm/s² predicted moderate or severe LV diastolic dysfunction with 89 % sensitivity and 89 % specificity (area under curve [AUC] = 0.903, P <0.0001). Application of this cutoff on test group showed 96 % sensitivity and 77 % specificity with AUC = 0.932 and P <0.0001.

Conclusion

AR of E wave of mitral inflow could be used for assessment of diastolic function, especially moderate or severe diastolic dysfunction. However, before its clinical application, external validation should be considered.

Early change in left atrial function in patients treated with anthracyclines assessed by real-time three-dimensional echocardiography

Real-time three-dimensional echocardiography(RT-3DE) has allowed a better assessment of LA volumes and function. We sought to assess the early change in left atrial size and function in patients treated with anthracyclines using RT-3DE. 61 patients aged 44.9 ± 11.9 years with large B-cell non-Hodgkin lymphoma treated with doxorubicin were studied. Blood collection and echocardiography were performed at baseline and 1 day after completion of the chemotherapy. Global longitudinal strain (GLS), maximum, minimum and pre-atrial contraction LA volumes were measured and reservoir, conduit and booster pump function were assessed. Despite normal LVEF, passive emptying percent of total emptying (0.51 ± 0.14 vs. 0.40 ± 0.12, P < 0.001) and passive emptying index (0.29 ± 0.10 vs. 0.23 ± 0.06, P < 0.001) were remarkably reduced compared to baseline values, while active emptying percent of total emptying (0.49 ± 0.14 vs. 0.60 ± 0.12, P < 0.001) and active emptying index (0.41 ± 0.16 vs. 0.47 ± 0.16, P = 0.048) were increased. GLS (−21.64 ± 2.83 vs. −17.30 ± 2.50) was markedly reduced, cTnT levels was elevated from 0.005 ± 0.004 to 0.020 ± 0.026 ng/mL at the completion of chemotherapy (P all  < 0.001). Early LA functional change occur after doxorubicin exposure in patients with preserved LVEF, which could be detected by RT-3DE.

Can we diagnose isolated, exercise-induced heart failure with normal ejection fraction?

BACKGROUND

A significant proportion of patients with exertional dyspnea require exercise to diagnose heart failure with normal ejection fraction (HFNEF).

METHODS AND RESULTS

In this review article, we evaluate current data on the prevalence, clinical significance and specifically the establishment of a diagnosis of isolated, exercise-induced HFNEF. Despite the unquestioned clinical importance and high prevalence of exercise-induced HFNEF, there are limited and conflicting data on making a diagnosis of exercise-induced HFNEF. This mostly relies on the evidence of exercise-induced elevation in left ventricular filling pressure (LVFP). At present, there is no agreement on the ability of exercise echocardiographic parameteres to predict exercise-induced LVFP elevation. In addition, even invasively measured exercise LVFP faces the problem of defining normal exercise LVFP values. More data and probably new diagnostic approaches are necessary to reliably diagnose exercise HFNEF.

CONCLUSIONS

There are conflicting results and significant problems associated with the diagnosis of exercise HFNEF. This review hopefully will encourage further research in this difficult but clinically important area of heart failure.

Simultaneous pressure-volume measurements using optical sensors and MRI for left ventricle function assessment during animal experiment

Simultaneous pressure and volume measurements enable the extraction of valuable parameters for left ventricle function assessment. Cardiac MR has proven to be the most accurate method for volume estimation. Nonetheless, measuring pressure simultaneously during MRI acquisitions remains a challenge given the magnetic nature of the widely used pressure transducers. In this study we show the feasibility of simultaneous in vivo pressure-volume acquisitions with MRI using optical pressure sensors. Pressure-volume loops were calculated while inducing three inotropic states in a sheep and functional indices were extracted, using single beat loops, to characterize systolic and diastolic performance. Functional indices evolved as expected in response to positive inotropic stimuli. The end-systolic elastance, representing the contractility index, the diastolic myocardium compliance, and the cardiac work efficiency all increased when inducing inotropic state enhancement. The association of MRI and optical pressure sensors within the left ventricle successfully enabled pressure-volume loop analysis after having respective data simultaneously recorded during the experimentation without the need to move the animal between each inotropic state.

Acute improvement of left ventricular relaxation as a predictor of volume reduction after cardiac resynchronization therapy: a pilot study assessing the value of left ventricular hemodynamic parameter

BACKGROUND

Cardiac resynchronization therapy (CRT) improves cardiac function, but CRT recipients with advanced heart failure (HF) do not always respond well. Because the best parameters for the prediction of CRT response are not established, we investigated whether improvement of invasive left ventricular (LV) hemodynamic diastolic parameters could identify CRT responders.

METHODS

A total of 34 consecutive patients (age, 69 ± 9 years; 70% men) who received CRT devices for HF were assessed as to whether acute invasive hemodynamic parameters with and without CRT function could predict LV volume responders.

RESULTS

These patients demonstrated an improvement in LV dP/dtmax (11.1 ± 11.7%), LV dP/dtmin (4.6 ± 12.1%), and tau (3.7 ± 11.6%) by biventricular pacing. Nineteen patients (55%) were classified as CRT responders, which was defined by a >15% decrease in LV end-systolic volume (ESV) at the 6-month follow-up evaluation. The area under the receiver operator characteristic curve to detect CRT volume response was 0.93 for the shortening of tau, which was superior to any other hemodynamic parameter. The multivariate analysis revealed that this improvement in tau was the strongest predictive factor for identifying CRT volume responders. Of note, the magnitude of tau shortening during biventricular pacing was significantly correlated with the reduction in LVESV at the 6-month follow-up evaluation.

CONCLUSIONS

The extent of acute improvement in LV isovolumic relaxation time, as assessed by tau, was associated with favorable response to CRT. The assessment of invasive diastolic function could provide valuable information about CRT volume response.

Tissue doppler myocardial performance index in patients with heart failure and its relationship with haemodynamic parameters

The myocardial performance index (MPI) reflects both the systolic and diastolic function of the heart, and is easily applied in practice. In this study, we aimed to determine the relationship between MPI and invasive haemodynamic parameters in heart failure patients. A total of 126 patients with heart failure were selected, all of whom were referred for diagnostic cardiac catheterisation, and were divided into two groups. Group I consisted of 59 patients (32 men and 27 women, mean age 61 ± 10; functional capacity New York Heart Association (NYHA) Class I; and left ventricular end-diastolic pressure (LVEDP) <16 mmHg). Group II included 67 patients (34 men and 33 women, mean age 60 ± 9; NYHA Class ≥ II; LVEDP ≥ 16 mmHg). The following parameters were measured in all patients: ejection fraction with Simpson method, the peak mitral early (E) and late (A) diastolic velocities, E/A ratio, deceleration time (DT) and tissue Doppler from four different areas of the mitral annulus (septum, lateral, inferior and anterior). In order to measure MPI with two methods (standard Doppler and tissue Doppler), isovolumetric contraction time (IVCT), isovolumetric relaxation time (IVRT) and ejection time (ET) were measured from four areas and mean values of MPI were calculated. There was no difference between the two groups in E/A ratios, DT and IVRT (p > 0.05). Group II patients had longer IVCT and ET, when compared with group I patients (p < 0.05). MPI, measured by both standard pulsed wave Doppler and tissue Doppler methods, was significantly higher in group II patients, when compared with the values obtained from group I patients (Group I: 0.50 ± 0.2 and 0.50 ± 0.14; group II: 0.98 ± 0.3 and 1.2 ± 0.32; p < 0.001). According to receiver operating characteristics curve analysis, the cut-off value for MPI measured by tissue Doppler was 0.74. The sensitivity and specificity of this value were measured as 92.5 and 91.5%, respectively. MPI measured by standard Doppler method was 0.67, and its sensitivity and specificity were 85.1 and 83.1%, respectively. We found a strong relationship between MPI and LVEDP (r = 0.83, p < 0.001; r = 0.96, p < 0.001), especially when measured by tissue Doppler. In addition, we observed a significant relationship between the MPI values measured by tissue Doppler and those measured by standard traditional methods (r = 0.85, p < 0.001). We showed that MPI was reliable for the evaluation of global cardiac functions in patients with heart failure, as measured with both pulsed-wave Doppler and tissue Doppler. We assert that, in order to differentiate between those patients with symptomatic heart failure from the asymptomatic cases, MPI as measured with the tissue Doppler method is an improvement on MPI as measured using traditional methods.

Rapid onset of cardiomyopathy in STZ-induced female diabetic mice involves the downregulation of pro-survival Pim-1

Background

Diabetic women are five times more likely to develop congestive heart failure compared with two fold for men. The underlying mechanism for this gender difference is not known. Here we investigate the molecular mechanisms responsible for this female disadvantage and attempt safeguarding cardiomyocytes viability and function through restoration of pro-survival Pim-1.

Methods and Results

Diabetes was induced by injection of streptozotocin in CD1 mice of both genders. Functional and dimensional parameters measurement using echocardiography revealed diastolic dysfunction in female diabetic mice within 8 weeks after STZ-induced diabetes. This was associated with significant downregulation of pro-survival Pim-1 and upregulation of pro-apoptotic Caspase-3, microRNA-1 and microRNA-208a. Male diabetic mice did not show any significant changes at this time point (P < 0.05 vs. female diabetic). Further, the onset of ventricular remodelling was quicker in female diabetic mice showing marked left ventricular dilation, reduced ejection fraction and poor contractility (P < 0.05 vs. male diabetic at 12 and 16 weeks of STZ-induced diabetes). Molecular analysis of samples from human diabetic hearts confirmed the results of pre-clinical studies, showing marked downregulation of Pim-1 in the female diabetic heart (P < 0.05 vs. male diabetic). Finally, in vitro restoration of Pim-1 reversed the female disadvantage in diabetic cardiomyocytes.

Conclusions

We provide novel insights into the molecular mechanisms behind the rapid onset of cardiomyopathy in female diabetics. These results suggest the requirement for the development of gender-specific treatments for diabetic cardiomyopathy.

Evaluation of cardiac functions of infants of diabetic mothers using tissue Doppler echocardiography

AIM

Transient cardiac hypertrophy occurs in infants of diabetic mothers. The effect of this state on cardiac functions was investigated with a case-control study using tissue Doppler technique.

MATERIAL AND METHODS

In this study, right and left ventricle systolic and diastolic functions of 45 term babies of diabetic mothers and 50 healthy term newborns were examined using tissue Doppler echocardiography.

RESULTS

The septum was found to be thick in 16 (36%) of the babies of diabetic mothers. Both the left and right ventricle myocardial velocities were found to be lower in the babies of diabetic mothers compared to the control group. In our study, the Em/Am ratio was found to be below one only in the babies of diabetic mothers in the left ventricle in contrast to the control group. In addition, the Em/Am ratio in the septum and right ventricle was found to be below one both in the babies of diabetic mothers (group 1, 2) and control group. The calculated Tei index was found to be higher in the babies of diabetic mothers who had a thicker interventricular septum compared to the control group.

CONCLUSION

Interventricular septal thickening in babies of diabetic mothers disrupt the diastolic function of both ventricles. This can be demonstrated by tissue Doppler echocardiography. These results show that diastolic function is disrupted in both ventricles in babies of diabetic mothers and only in the right ventricle in healthy babies. It was thought that this could be explained by right ventricular dysfunction arising from physiological pulmonary hypertension in the neonatal period. Subclinical right and left ventricular diastolic dysfunctions which we found by tissue Doppler indicate that babies of diabetic mothers especially with a thick septum should be closely monitored.

Topology of blood transport in the human left ventricle by novel processing of Doppler echocardiography

Novel processing of Doppler-echocardiography data was used to study blood transport in the left ventricle (LV) of six patients with dilated cardiomyopathy and six healthy volunteers. Bi-directional velocity field maps in the apical long axis of the LV were reconstructed from color-Doppler echocardiography. Resulting velocity field data were used to perform trajectory-based computation of Lagrangian coherent structures (LCS). LCS were shown to reveal the boundaries of blood injected and ejected from the heart over multiple beats. This enabled qualitative and quantitative assessments of blood transport patterns and residence times in the LV. Quantitative assessments of stasis in the LV are reported, as well as characterization of LV vortex formations from E-wave and A-wave filling.

Fluid-structure interaction of an aortic heart valve prosthesis driven by an animated anatomic left ventricle

We develop a novel large-scale kinematic model for animating the left ventricle (LV) wall and use this model to drive the fluid-structure interaction (FSI) between the ensuing blood flow and a mechanical heart valve prosthesis implanted in the aortic position of an anatomic LV/aorta configuration. The kinematic model is of lumped type and employs a cell-based, FitzHugh-Nagumo framework to simulate the motion of the LV wall in response to an excitation wavefront propagating along the heart wall. The emerging large-scale LV wall motion exhibits complex contractile mechanisms that include contraction (twist) and expansion (untwist). The kinematic model is shown to yield global LV motion parameters that are well within the physiologic range throughout the cardiac cycle. The FSI between the leaflets of the mechanical heart valve and the blood flow driven by the dynamic LV wall motion and mitral inflow is simulated using the curvilinear immersed boundary (CURVIB) method [1, 2] implemented in conjunction with a domain decomposition approach. The computed results show that the simulated flow patterns are in good qualitative agreement with in vivo observations. The simulations also reveal complex kinematics of the valve leaflets, thus, underscoring the need for patient-specific simulations of heart valve prosthesis and other cardiac devices.

Arterial stiffness, carotid atherosclerosis and left ventricular diastolic dysfunction in postmenopausal women

BACKGROUND

Postmenopausal women have an increased cardiovascular morbidity that may be due to the increase in classical cardiovascular risk factors and also to the arterial structure and function alterations. The aim of our study was to evaluate the association of aortic pulse wave velocity (PWV), and carotid intima-media thickness (IMT), with left ventricular diastolic dysfunction (LVDD) in postmenopausal women.

PATIENTS AND METHODS

In 96 women without overt cardiovascular disease (age 62±7.7 years), and with normal left ventricular systolic function, aortic PWV was assessed by using an oscillometric device, intima-media thickness was measured by B-mode ultrasonography and the parameters of left ventricular diastolic function were evaluated by a transthoracic echocardiographic study.

RESULTS

LVDD, defined as an E/A ratio≤1 was found in 50 patients (52%). All of them had mild LVDD. In these patients we found significant increase in age (p<0.001), aortic PWV (p<0.001), carotid IMT (p=0.002) and plaque score (p=0.004) when compared with patients without LVDD. In a logistic regression analyzed, after adjusting for age, only aortic PWV was a significant predictor of LVDD (2.15, 95% CI 1.39-3.31, p=0.0006).

CONCLUSIONS

This study among postmenopausal women provides evidence that increased arterial stiffness as measured by aortic PWV and not carotid IMT may be a marker or a risk factor for LVDD, independent of other classical risk factors.

Early diastolic functional abnormalities in normotensive offspring of Nigerian hypertensives

Background

Some studies have suggested that diastolic dysfunction precedes the clinical manifestation of hypertension. Whether changes in cardiac structure and function predate the clinical manifestation of hypertension later in life is now being investigated. The aim of this study was to assess the differences in cardiac structure and function between the offspring of hypertensive and normotensive parents.

Methods

Eighty normotensive offspring of hypertensive parents (OHyp) (41 females and 39 males) and 62 normotensive offspring of normotensive parents (ONorm) (31 males and 31 females) were recruited for echocardiography.

Results

The mean age was 25.0 (5.31) and 24.3 (3.60) years in the OHyp and ONorm participants, respectively (p = 0.369). Other baseline parameters were comparable between the two groups. Septal wall thickness in systole was higher in the OHyp than the ONorm subjects [1.3 (0.35) vs 1.1 (0.25), p = 0.0173]. Indexed left ventricular mass [28.1 (7.33) vs 27.5 (7.23), p = 0.631] and relative wall thickness [(0.3 (0.10) vs 0.3 (0.90), p = 0.280] were similar in the two groups. The offspring of hypertensives had lower deceleration time [149.9 (38.89) vs 169.0 (50.08) ms, p = 0.012], prolonged duration of pulmonary A reverse flow [113.5 (70.69) vs 81.7 (38.31) ms, p = 0.024], increased myocardial isovolumic relaxation time [173.4 (47.98) vs 156.1 (46.74) ms, p = 0.033] and a lower myocardial Em [0.2 (0.05) vs 0.3 (1.38), p = 0.037] and myocardial Em/Am ratio [1.6 (0.01) vs 2.1 (0.01), p = 0.019] than the offspring of normotensives.

Conclusion

This study showed that offspring of OHyp subjects had early diastolic functional abnormalities when compared with offspring of ONorm participants. Longitudinal studies are needed to determine the implications of this finding in this African population.

Clinical implication of mechanical dyssynchrony in heart failure

Mechanical dyssynchrony is a common phenomenon in patients with congestive heart failure, which usually identified by noninvasive cardiac imaging tools such as echocardiography. It demonstrates electromechanical delay in some regions of the failing heart which in turn contributes to further impairment of cardiac function. The diagnostic, therapeutic and prognostic values of mechanical dyssynchrony have been reported in a number of studies. Therefore, this review describes briefly the methods of measurement, but more importantly, explains the clinical implication of its assessment in heart failure related aspects including cardiac resynchronization therapy, functional mitral regurgitation, diastolic heart failure and mortality.

Is myocardial performance index useful in differential diagnosis of moderate and severe hypoxic-ischaemic encephalopathy? A serial Doppler echocardiographic evaluation

INTRODUCTION

The aim of this study was to investigate the importance of myocardial performance index as an additive criterion to Sarnat criteria in differential diagnosis of newborn babies with moderate and severe hypoxic-ischaemic encephalopathy.

METHODS

Our study group included 50 healthy term newborn babies and 20 newborn babies with hypoxic-ischaemic encephalopathy. The 20 newborn babies with hypoxic-ischaemic encephalopathy were scored using Sarnat grades. Left and right ventricular functions were determined on the first day and thereafter in the 1, 3-4, 6-7, and 11-12 months of life by M-Mode and pulsed Doppler.

RESULTS

Myocardial performance indexes of the left ventricle were significantly higher in the severe hypoxic-ischaemic encephalopathy group than in the control group during the first, second, and third analyses (p = 0.01, p = 0.02, p = 0.02, respectively) and only during the first analysis (p = 0.01) in the moderate hypoxic-ischaemic encephalopathy group. In addition, the myocardial performance indexes of the right ventricle were significantly higher during the first, second, and third analyses in both severe and moderate hypoxic-ischaemic encephalopathy groups than in the control group (p = 0.01, all). Hypoxia-induced alterations last longer in the right ventricle than in the left ventricle in the moderate group, as during the second and third analyses myocardial performance index continues to be higher than the control group.

CONCLUSION

Myocardial performance indexes for the left and right ventricles were significantly higher in both severe and moderate hypoxic-ischaemic encephalopathy groups than in the control group during the first analysis, and myocardial performance index greater than or equal to 0.5 can be used in order to distinguish moderate and severe hypoxic-ischaemic encephalopathy babies according to Sarnat grades as a discriminative additive criterion.

The clinical value of the Tei index among Nigerians with hypertensive heart failure: correlation with other conventional indices

BACKGROUND

Various conventional methods are used for functional evaluation and risk stratification in heart failure. A combined index of global myocardial performance called the Tei index has been described. The aim of this study was to evaluate the correlation of the Tei index with other conventional indices of systolic and diastolic function among Nigerians with hypertensive heart failure.

METHODS

Fifty-five subjects with hypertensive heart failure and 30 controls were examined, a clinical history was taken, and echocardiography was performed on them. The subjects were categorised into four groups based on their ejection fraction (normal ejection fraction, mild, moderate and severe heart failure). The Tei index was calculated as the sum of the isovolumic relaxation and contraction time, divided by the ejection time. Statistical analysis was done using SPSS 16.0.

RESULTS

The Tei index was significantly higher among subjects with hypertensive heart failure compared with the controls (0.91 ± 0.33 vs 0.28 ± 0.16, p < 0.005). The Tei index also increased with the severity of the heart failure and was inversely correlated with ejection fraction (r = -0.697, p < 0.001) and fractional shortening (r = -0.580, p = 0.001). It was directly correlated with mitral E/A ratio (r = 0.246, p = 0.030), left ventricular internal diastolic dimension (r = 0.414, p = 0.002), left ventricular internal systolic dimension (r = 0.596, p < 0.001) and deceleration time (r = 0.219, p = 0.032).

CONCLUSION

The Tei index correlated significantly with other conventional indices of systolic and diastolic function among Nigerians with hypertensive heart failure. It can be used as a risk-stratification index similar to other traditional indices of systolic and diastolic function.

Aging change of left ventricular function in children evaluated by acoustic quantification method

BACKGROUND

There are few reports about acoustic quantification (AQ) in the area of pediatrics. We aim to determine normal values of AQ analysis and investigate the aging change of left ventricular function in children.

METHODS

The subjects in this study included 137 patients (aged 29 days to 18 years) who had normal cardiac function and no cardiac load. None of the patients were receiving medical therapy. The instrument used was a PH-6500 (Philips, Andevor). Change of left ventricular area in short-axis view was detected by AQ analysis. From the mitral inflow, peak early (E) and peak late (A) diastolic velocities were measured, and E/A was calculated.

RESULTS

End-diastolic area (EDA) and end-systolic area (ESA) increased with age. Fractional area change (FAC) decreased with age. Peak ejection rate (PER) and peak rapid filling rate (PRFR) decreased with age up to 10 years. Atrial filling fraction (AFF) decreased and E/A increased with age up to 5 years.

CONCLUSIONS

Maturational or developmental alterations in LV diastolic properties were found up to 5 years old. AQ analysis is one of the useful indexes for investigating left ventricular diastolic function.

Perioperative assessment of diastolic dysfunction

Assessment of diastolic function should be a component of a comprehensive perioperative transesophageal echocardiographic examination. Abnormal diastolic function exists in >50% of patients presenting for cardiac and high-risk noncardiac surgery, and has been shown to be an independent predictor of adverse postoperative outcome. Normalcy of systolic function in 50% of patients with congestive heart failure implicates diastolic dysfunction as the probable etiology. Comprehensive evaluation of diastolic function requires the use of various, load-dependent Doppler techniques This is further complicated by the additional effects of dehydration and anesthetic drugs on myocardial relaxation and compliance as assessed by these Doppler measures. The availability of more sophisticated Doppler techniques, e.g., Doppler tissue imaging and flow propagation velocity, makes it possible to interrogate left ventricular diastolic function with greater precision, analyze specific stages of diastole, and to differentiate abnormalities of relaxation from compliance. Additionally, various Doppler-derived ratios can be used to estimate left ventricular filling pressures. The varying hemodynamic environment of the operating room mandates modification of the diagnostic algorithms used for ambulatory cardiac patients when left ventricular diastolic function is evaluated with transesophageal echocardiography in anesthetized surgical patients.

Comparison of left atrial phasic function in hypertrophic cardiomyopathy versus systemic hypertension using strain rate imaging

The aim of this study was to determine if left atrial (LA) phasic function evaluated by Doppler tissue imaging-derived strain and strain rate would be differentially decreased in patients with hypertrophic cardiomyopathy (HC) compared to patients with hypertension and to normal controls. Thirty-seven patients with HC were compared to 44 patients with systemic hypertension (SH) and 65 normal controls using transthoracic echocardiography. Maximal and minimal LA volume and LA volume just before active atrial contraction (pre-P LA volume) were measured, and phasic LA volumes were calculated. Global and segmental systolic strain rate, early diastolic strain rate, and late diastolic strain rate (A-Sr) and strain were measured from Doppler tissue imaging. Left ventricular mass was increased in the HC and SH groups compared to normal controls, but diastolic dysfunction was greater in the HC group. LA volumes were increased in patients with HC compared to those with SH and to normal controls, with corresponding reductions in A-Sr and atrial strain in the HC group. In contrast, only early diastolic strain rate was decreased in the SH group compared to controls. A-Sr remained reduced in patients with HC compared to the SH group, even after adjusting for left ventricular mass. When left ventricular mass, parameters of diastolic function (peak E and E' velocity), and the effect of patient group (SH vs HC) were examined in a stepwise regression model, patient group (SH vs HC) was the only independent determinant of A-Sr. In conclusion, HC results in LA enlargement with reduced LA phasic function that is reflected in reductions in A-Sr and atrial strain. Atrial enlargement is a likely consequence of the greater diastolic dysfunction in the HC group.

High temporal resolution SSFP cine MRI for estimation of left ventricular diastolic parameters

PURPOSE

To obtain high temporal resolution (HTR) magnetic resonance (MR) steady-state free-precession (SSFP) cine cardiac images by using multichannel radiofrequency (RF) hardware and parallel imaging techniques; to study the effect of temporal resolution; and to compare the derived left ventricular (LV) diastolic filling parameters with echocardiographic results.

MATERIALS AND METHODS

HTR images were acquired in 13 healthy volunteers using a 1.5 T scanner with 32 RF channels and sensitivity encoding (SENSE) and k-t broad-use linear-acquisition speedup technique (k-t BLAST) imaging techniques. LV diastolic parameters were calculated and compared to conventional echocardiographic indices such as the isovolumic relaxation time (IVRT) and E/A ratio. The need for HTR was assessed and the MR results were compared with echocardiographic results.

RESULTS

The HTR (approximately 6-ms) images yielded higher peak filling rates, peak ejection rates, and peak atrial filling rates. A progressive decline in filling and ejection rates was observed with worsening temporal resolution. The IVRTs and E/A ratios measured with MR versus echocardiography were in broad agreement. Also, SENSE and k-t BLAST yielded similar diastolic functional parameters.

CONCLUSION

With SENSE or k-t BLAST and modern hardware, HTR cine images can be obtained. The lower temporal resolutions (30-50 ms) used in clinical practice reduce LV filling rates by <or=30% and may hinder characterization of transient phenomena such as the IVRT.

Effect of systemic hypertension on right ventricular morphology and function: an echocardiographic study

BACKGROUND

Hypertension is an important cardiovascular risk factor worldwide. It is associated with left ventricular hypertrophy (LVH). Both diastolic and systolic dysfunction may occur in hypertensive heart disease. The ventricles are structurally and functionally interdependent on each other. This was an echocardiographic study intended to describe the impact of left ventricular pressure overload and hypertrophy due to hypertension on right ventricular morphology and function.

METHODS

One hundred subjects with systemic hypertension and 50 age- and gender-matched normotensive control subjects were used for this study. Two-dimensional (2-D), M-mode and Doppler echocardiographic studies were done to evaluate the structure and function of both ventricles. Data analysis was done using the SPSS 16.0 (Chicago, Ill). Statistical significance was taken as p < 0.05.

RESULTS

Age and gender were comparable between the two groups. Hypertensive subjects had significantly increased left ventricular end-diastolic dimensions, posterior wall thickness, interventricular septal thickness, left atrial dimensions and left ventricular mass and index. The mitral valve E/A ratio was reduced among hypertensive subjects when compared to normal controls (1.15 ± 0.75 vs 1.44 ± 0.31, respectively; p < 0.05). A similar pattern was found in the tricuspid E/A ratio (1.14 ± 0.36 vs 1.29 ± 0.30, respectively; p < 0.05). Hypertensive subjects also had reduced right ventricular internal dimensions (20.7 ± 8.0 vs 23.1 ± 3.1 mm, respectively; p < 0.001) but similar peak pulmonary systolic velocity. The mitral e/a ratio correlated well with the tricuspid e/a ratio.

CONCLUSION

Systemic hypertension is associated with right ventricular morphological and functional abnormalities. Right ventricular diastolic dysfunction may be an early clue to hypertensive heart disease.

Pulsed and Tissue Doppler Echocardiographic Changes in Patients with Thalassemia Major

Background

Doppler echocardiographic studies of left ventricle (LV) systolic and diastolic function in patients with β-Thalassemia Major (β-TM) had shown different patterns of systolic and diastolic dysfunction.

Aim

This cross-sectional study was designed to study the LV systolic and diastolic function in patients with β-TM using Pulsed Doppler (PD) and Tissue Doppler (TD) echocardiography.

Methods

All patients were evaluated clinically and by echocardiography, The study included patients with β-TM (n = 38, age 15.7 ± 8.9 years) compared with an age-matched control group (n = 38, age 15.9 ± 8.9 years). The pulse Doppler indices were normalized for age and heart rate.

Results

Compared with control patients, M-Mode showed that patients with β-TM have thicker LV septal wall index (0.659 ± 0.23 vs. 0.446 ± 0.219 cm, P ≤ 0.001), posterior wall index (0.659 ± 0.235 vs. 0.437 ± 0.214 cm, P ≤ 0.01), and larger LVEDD index is (3.99 ± 0.48 vs. 2.170 ± 0.57 mm. P = 0.035). Pulsed Doppler showed high LV trans-mitral E wave velocity (70.818 ± 10.139 vs. 57.532 ± 10.139, p = 0.027) and E/A ratio (1.54 vs. 1.23, P ≤ 0.01). The duration of Deceleration time (DT) and isovolumic relaxation time (IVRT) were significantly shorter in patients with β-TM (150.234 ± 20.0.23 vs. 167.123 ± 19.143 msec, P ≤ 0.01) and (60.647 ± 6.77 vs. 75.474 ± 5.83 msec, P ≤ 0.001), respectively. The ratio of transmitral E wave velocity to the tissue Doppler E wave at the basal septal mitral annulus E/Em–was significantly higher in β-TM group (14.024 ± 2.29 vs. 12.132 ± 1.82, P ≤ 0.01). The Tissue Doppler systolic velocity (Sm) and the early diastolic velocity (Em) were significantly lower in β-TM group compared to control (4.31 ± 1.2 cm/s vs. 6.95 ± 2.1, P ≤ 0.01 and 4.31 ± 2.7 cm/s vs. 5.82 ± 2.5, P ≤ 0.01) respectively. The tricuspid valve velocity was significantly higher than controls (2.993 ± 0.569 vs. 1.93 ± 0.471 m/sec, respectively, P ≤ 0.01). However, the LVEF% and fractional shortening were normal with no significant difference in both groups.

Conclusion

In this study, patients with β-thalassemia major compared with controls, have significantly thicker LV wall, and larger LV cavity and LV diastolic filling indices suggestive of restrictive pattern with a higher tricuspid valve velocity. These data showed that left ventricle diastolic indices are compromised initially in patients with β-thalassemia major.

Evaluation of left ventricular diastolic function from the pattern of left ventricular filling

The pattern of left ventricular (LV) filling can be determined by Doppler echocardiography. Normally most LV filling occurs early in diastole, with some additional filling occurring during atrial systole, late in diastole. In the absence of mitral stenosis, three patterns of LV filling indicate progressively greater diastolic dysfunction: (1) Reduced early diastolic filling with a compensatory increase in importance of atrial filling, termed a pattern of "impaired relaxation;" (2) "pseudo-normalization" with most filling early in diastole but with rapid deceleration of mitral flow; and (3) "restricted filling" with almost all filling of the LV occurring very early in diastole in association with very rapid deceleration of mitral flow. A large, prolonged atrial regurgitant flow in the pulmonary veins also indicates impaired diastolic performance. The time for early filling deceleration is predominantly determined by LV stiffness: the shorter the deceleration time, the stiffer the LV. Patients with short deceleration time have a poor prognosis.

Dual ACE-inhibition and AT1 receptor antagonism improves ventricular lusitropy without affecting cardiac fibrosis in the congenic mRen2.Lewis rat

BACKGROUND

Hypertension and left ventricular (LV) hypertrophy often precede diastolic dysfunction and are risk factors for diastolic heart failure. Although pharmacologic inhibition of the renin-angiotensin system (RAS) improves diastolic function and functional capacity in hypertensive patients with LV hypertrophy, the effects of combination therapy with an angiotensin converting enzyme inhibitor (ACEi) and an angiotensin receptor blocker (ARB) are unclear.

METHOD

We assessed the effects of the combined 10-week administration of lisinopril (10 mg/kg/ day, p.o.) and losartan (10 mg/kg/day, p.o.) (LIS/LOS) on diastolic function and LV structure in seven young (5 weeks), prehypertensive congenic mRen2.Lewis male rat, a model of tissue renin overexpression and angiotensin II (Ang II)-dependent hypertension compared to vehicle (VEH) treated (n = 7), age-matched rats.

RESULTS

Systolic blood pressures were 64% lower with the combination therapy (p < 0.001), but there were no differences in heart rate or systolic function between groups. RAS inhibition increased myocardial relaxation, defined by tissue Doppler mitral annular descent (e') by 2.2 fold (p < 0.001). The preserved lusitropy in the LIS/LOS-treated rats was accompanied by a reduction in phospholamban-to-SERCA2 ratio (p < 0.001). Despite lower relative wall thicknesses (VEH: 1.56+/-0.17 versus LIS/LOS: 0.78+/-0.05) and filling pressures, defined by the transmitral Doppler-to-mitral annular descent ratio (E/e', VEH: 28.7+/-1.9 versus LIS/LOS: 17.96+/-1.5), no differences in cardiac collagen were observed.

CONCLUSION

We conclude that the lusitropic benefit of early dual RAS blockade may be due to improved vascular hemodynamics and/or cardiac calcium handling rather than effects on extracellular matrix reduction.