Tissue Doppler echocardiography

Cardiac functions in children with steroid-sensitive nephrotic syndrome

BACKGROUND

The aim of the present study was to evaluate the presence of cardiac systolic and diastolic dysfunction in pediatric patients with steroid-sensitive nephrotic syndrome (NS).

METHODS

The study population consisted of 19 patients with debut-relapse of NS aged 1-18 years and 30 sex and age-matched healthy controls. Blood and urine samples, two M-mode conventional echocardiograms and tissue Doppler velocity imaging were evaluated in both attack and remission periods.

RESULTS

With regard to conventional pulse wave Doppler (cPWD), steroid-sensitive NS patients (both in debut / relapse and in remission periods) had a higher peak of late diastolic flow velocities (A peak), and patients in debut / relapse had a lower E/A ratio than the control group, indicating diastolic dysfunction (overall P = 0.003 and P = 0.006, respectively). Based on tissue Doppler velocity imaging echocardiography results, patients in debut/relapse had a higher A' and a lower E'/A' ratio (overall P < 0.001 and P = 0.001, respectively). There was also a significant difference in the cPWD E/TDI E' ratio between the patients showing an increased cPWD E/TDI E' ratio in remission periods compared to in debut/relapse periods (P = 0.09). The albumin levels were positively correlated with E'/A' and E/ E' ratio (r = 0.609; P = 0.007, r = 0.472; P = 0.041 respectively).

CONCLUSIONS

Systolic cardiac functions are preserved but diastolic functions are affected in steroid-sensitive NS patients both in debut/relapse and in remission periods in a relatively short time. The persistence of left ventricular (LV) dysfunction during the remission period requires special attention during the follow up for early detection of cardiac abnormalities.

Impaired Systolic and Diastolic Left Ventricular Function in Children with Chronic Kidney Disease - Results from the 4C Study

Children with chronic kidney disease suffer from excessive cardiovascular mortality and early alterations of the cardiovascular system. Tissue doppler imaging is a validated echocardiographic tool to assess early systolic and diastolic cardiac dysfunction. We hypothesized that tissue Doppler velocities would reveal reduced cardiac function in children with chronic kidney disease compared to healthy children. A standardized echocardiographic exam was performed in 128 patients of the Cardiovascular Comorbidity in Children with Chronic Kidney Disease (4C) Study aged 6–17 years with an estimated glomerular filtration rate (eGFR) below 60 ml/min/1.73 m². Tissue Doppler measurements included early (E’) and late (A’) diastolic and systolic (S’) velocity at the mitral and septal annulus of the left ventricle. Measured values were normalized to z-scores using published reference data. Predictors of E’/A’, E/E’, S’ and left ventricular mass index (LVMI) were assessed by multiple linear regression analyses. Tissue Doppler E’ was reduced and tissue Doppler A’ increased, resulting in a reduced tissue Doppler E’/A’ ratio (z-score −0.14, p < 0.0001) indicating reduced diastolic function compared to healthy children. Reduced tissue Doppler E’/A’ Z-Scores were independently associated with lower eGFR (p = 0.002) and increased systolic blood pressure (p = 0.02). While E/E’ Z-Scores were increased (Z-score 0.57, p < 0.0001), patients treated with pharmacological RAS blockade but not with other antihypertensive treatments had significantly lower E/E’ and higher E’/A’ Z-Scores. Systolic tissue Doppler velocities were significantly decreased (Z-score −0.24, p = 0.001) and inversely correlated with E/E’ Z-Scores (r = −0.41, p < 0.0001). LVMI was not associated with systolic or diastolic tissue Doppler velocities. Concentric left ventricular hypertrophy showed a tendency to lower S’ in multivariate analysis (p = 0.13) but no association to diastolic function. Concentric left ventricular geometry was significantly associated with lower midwall fractional shortening. In summary, systolic and diastolic function assessed by tissue Doppler is impaired. eGFR, systolic blood pressure and the type of antihypertensive medications are significant predictors of diastolic function in children with CKD. Left ventricular morphology is largely independent of tissue Doppler velocities. Tissue Doppler velocities provide sensitive information about early left ventricular dysfunction in this population.

Robust Tracking of Small Displacements With a Bayesian Estimator

Radiation-force-based elasticity imaging describes a group of techniques that use acoustic radiation force (ARF) to displace tissue to obtain qualitative or quantitative measurements of tissue properties. Because ARF-induced displacements are on the order of micrometers, tracking these displacements in vivo can be challenging. Previously, it has been shown that Bayesian-based estimation can overcome some of the limitations of a traditional displacement estimator such as normalized cross-correlation (NCC). In this work, we describe a Bayesian framework that combines a generalized Gaussian-Markov random field (GGMRF) prior with an automated method for selecting the prior's width. We then evaluate its performance in the context of tracking the micrometer-order displacements encountered in an ARF-based method such as ARF impulse (ARFI) imaging. The results show that bias, variance, and mean-square error (MSE) performance vary with prior shape and width, and that an almost one order-of-magnitude reduction in MSE can be achieved by the estimator at the automatically selected prior width. Lesion simulations show that the proposed estimator has a higher contrast-to-noise ratio but lower contrast than NCC, median-filtered NCC, and the previous Bayesian estimator, with a non-Gaussian prior shape having better lesion-edge resolution than a Gaussian prior. In vivo results from a cardiac, radio-frequency ablation ARFI imaging dataset show quantitative improvements in lesion contrast-to-noise ratio over NCC as well as the previous Bayesian estimator.

The effect of recombinant human growth hormone therapy on left-ventricular chamber size and function in children with growth hormone deficiency

This study was designed to assess the effect of recombinant human growth hormone (rhGH) therapy on left-ventricular (LV) chamber size and function in children with idiopathic isolated growth hormone deficiency (GHD) using conventional echocardiography and tissue Doppler imaging (TDI). Thirty patients (19 boys and 11 girls) with idiopathic isolated GHD were followed-up for 12 months. Mean age of patients was 11.0 ± 2.6 years (range 6.3-15.5). At baseline and at 3, 6, and 12 months of treatment, the structure of the left ventricle was assessed by conventional echocardiography and myocardial rates and time intervals by TDI. There was a significant increase in LV mass (LVM) compared with pretreatment values. Like LVM, relative wall thickness (RWT) was also increased significantly. The significant increase in LVM indexed to body surface area and RWT became apparent at month 3 of treatment with a significant increase in LVM indexed to height(2.7) at treatment month 6. Normalized LVM increased as early month 3 of treatment, and a steady increase was observed until month 12. However, no patient had LVM > +2 standard deviation scores at month 12 of treatment. No significant differences were observed in functional parameters of the left ventricle and the interventricular septum. The results of this study showed that rhGH therapy causes an increase in myocardial mass without changing the geometry or function of the myocardium. Therefore, the increase in myocardial mass appears to be concentric, thus causing remodeling instead of hypertrophy.

Role of echocardiography in the contemporary management of chronic heart failure

Echocardiography is an excellent noninvasive tool for the assessment of ventricular size and both systolic and diastolic function, and it is routinely used in patients with heart failure. This review will discuss the role of echocardiography in heart failure diagnosis, prognostic assessment and in the management of heart failure patients.

Flow in the left anterior descending coronary artery in patients with migraine headache

Migraine is a common neurovascular disorder characterized by attacks of severe headache, autonomic and neurologic symptoms. Migraine can affect many systems in the body, yet its effects on cardiovascular system are unclear. We hypothesized that migraine and coronary microvascular angina may be manifestations of a common systemic microvascular dysfunction and clinically associated. Forty patients with migraine and 35 healthy volunteers were included into the study. Using transthoracic Doppler echocardiography, coronary flow was visualized in the middle or distal part of the left anterior descending artery. Coronary diastolic peak flow velocities were measured with pulse wave Doppler at baseline and after dipyridamole infusion (0.56 mg/kg/4 min). Coronary flow reserve of <2 was considered normal. In addition, thorough 2-dimensional and Doppler echocardiographic examinations were also performed. Fifty-two women and 23 men were included. Coronary flow reserve was significantly lesser in the migraine group than in the control group (1.99 ± 0.3 vs 2.90 ± 0.5, p <0.05). In addition, mitral annular velocities were lower and the ratio of early mitral inflow velocity to early mitral annular velocity (E/E' lateral and E/E' septal) was higher in migraineurs than in the control group (p <0.05 for all), indicating diastolic function abnormalities in the migraine group. In conclusion, these findings suggest that there is an association between coronary microvascular dysfunction and migraine independently of the metabolic state of the patients. A common pathophysiologic pathway of impaired endothelial vasodilatation, vasomotor dysfunction, and increased systemic inflammatory factors may play a role in these 2 clinical conditions and could be the underlying cause of subclinical systolic and diastolic left ventricular dysfunction in migraineurs.

Left ventricular diastolic dysfunction by tissue Doppler echocardiography in pediatric chronic kidney disease

BACKGROUND

Myocardial dysfunction is common in chronic kidney disease (CKD) and related to poor outcomes. New non-invasive methods to assess cardiac function have been introduced, but comparative studies evaluating their clinical usefulness in pediatric CKD are lacking. We studied left ventricular (LV) function in pediatric CKD and renal transplant patients, comparing conventional pulse-wave Doppler echocardiography (cPWD) with newer tissue Doppler imaging (TDI) and relating the results to known cardiovascular risk factors.

METHODS

The study included 34 children/adolescents with CKD stages 2-5, 44 renal transplant patients and 19 patients with a normal renal function. The mean age was 11.4 (range 0.8-18.8) years.

RESULTS

Both patient groups had significantly lower LV diastolic function than those with a normal renal function. The most sensitive determinants were TDI E'/A' and cPWD E/TDI E' ratios. In a stepwise linear regression analysis, high blood pressure, young age and the presence of albuminuria all independently predicted LV diastolic function.

CONCLUSIONS

Our study confirms the high prevalence of LV diastolic dysfunction in pediatric CKD patients and following renal transplantation, where TDI appears to be more sensitive than cPWD in assessing early myocardial dysfunction. Our results also underline the importance of preventive measures, such as rigorous blood pressure control, in pediatric CKD.

Detection of subclinical atherosclerosis and diastolic dysfunction in patients with schizophrenia

BACKGROUND

Patients with schizophrenia have a higher risk for cardiovascular diseases, which is associated with early mortality compared with the nonschizophrenic population. Early diagnosis of cardiovascular diseases in asymptomatic periods in patients with schizophrenia would enhance their quality of life and reduce mortality. Echocardiography, carotid ultrasonography, and ankle brachial index (ABI) measurement are known to be beneficial methods of detecting subclinical cardiovascular diseases and of risk stratification. The present study investigated carotid intima media thickness (CIMT) and ABI and echocardiographic parameters measured via conventional and tissue Doppler echocardiography in patients with schizophrenia in comparison with a control group.

METHODS

The present case-control study included 116 patients with schizophrenia and 88 healthy patients. Participants with any current comorbid psychiatric disorder, current or lifetime neurological and medical problems, current coronary artery disease, diabetes, hypertension, hypothyroidism, or hyperthyroidism or who were using antihypertensives, antidiabetic agents, or antiobesity drugs were excluded. High-resolution B-mode ultrasound images were used to measure CIMT. Conventional and tissue Doppler measurements were performed according to the recommendations of the American Society of Echocardiography.

RESULTS

Low ABI, mitral ratio of the early (E) to late (A) ventricular filling velocities, septal E', septal S', lateral E', lateral S', septal E'/septal A', lateral E'/lateral A', and high septal A', mitral E/septal E', mitral E/lateral E', and CIMT values were observed in the schizophrenia group compared with the control group.

CONCLUSION

Doppler parameters supported the hypothesis that patients with schizophrenia are at high risk for cardiovascular diseases.

Assessment of cardiac functions using tissue Doppler imaging in children with familial Mediterranean fever

OBJECTIVE

Familial Mediterranean fever may carry a potential for cardiovascular disorders because of sustained inflammation during its course; however, there has been a limited number of studies investigating the cardiac functions in children. The aim of this study was to assess both ventricular diastolic functions using conventional echocardiography and tissue Doppler imaging in children with familial Mediterranean fever.

PATIENTS AND METHODS

The study population included 25 patients with familial Mediterranean fever - mean age was 11.8 plus or minus 5.30 years - and 23 healthy patients as controls - mean age was 9.88 plus or minus 3.69 years. Both ventricular functions were measured using echocardiography comprising standard M-mode and conventional Doppler and tissue Doppler imaging during an attack-free period.

RESULTS

The conventional echocardiographic parameters with myocardial performance index were in normal ranges and similar in patients with familial Mediterranean fever and controls, with a p-value more than 0.05. However, right ventricular diastolic dysfunction was observed in patients with familial Mediterranean fever documented by tissue Doppler imaging, with a p-value less than 0.05 for E't and A't wave ratio.

CONCLUSION

Using tissue Doppler imaging, we have demonstrated that although left ventricular functions were comparable in the patients and healthy children, right ventricular diastolic function indices were impaired in patients with familial Mediterranean fever during childhood. Impaired right ventricular diastolic function may be an early manifestation of cardiac involvement in children with familial Mediterranean fever.

Cardiac functions in children with growth hormone deficiency before and during growth hormone-replacement therapy

Childhood growth hormone deficiency (GHD) decreases left-ventricular (LV) mass, but impairment of cardiac function has never been documented. The objective of this study was to assess the cardiac effects of GHD and recombinant human growth hormone (rhGH) treatment using conventional echocardiography and tissue Doppler imaging. Complete two-dimensional, M-mode, pulse-wave Doppler echocardiography and pulse-wave tissue Doppler imaging were performed in 12 children (6 male and 6 female patients) with GHD at baseline and at 5.86 ± 1.61 months after rhGH therapy. Recombinant human growth hormone treatment was associated with a significant increase in LV mass index (63.8 ± 27.1 to 79.3 ± 30.3 g/m(2); P < 0.01) and LV internal dimensions (21.4 ± 2.63 to 24.0 ± 4.13 mm in systole [P = 0.03] and 36.5 ± 3.90 to 39.5 ± 4.94 mm in diastole [P < 0.01]). There were statistical differences of parameters, such as deceleration time of early peak velocity of mitral, isovolumic relaxation time, and myocardial performance index (103 ± 15.4 to 139 ± 21.2 ms [P < 0.01], 55.5 ± 9.24 to 69.2 ± 3.74 ms [P < 0.01], and 37.8 ± 4.46 to 44.9 ± 5.44% [P < 0.01], respectively). Before and during rhGH therapy, there were no significant differences in fractional shortening of the left ventricle, peak mitral, and tricuspid wave velocities with ratios determined using conventional echocardiography and tissue Doppler imaging. In children, GHD affects heart morphology by inducing a decrease in cardiac size, but it does not modify cardiac function. Recombinant human growth hormone treatment increases cardiac mass, deceleration time of early peak velocity of the mitral valve, isovolumic relaxation time, and myocardial performance index, but it does not make a difference in other parameters of conventional echocardiography and tissue Doppler imaging.

The effect of chronic pulmonary hypertension on diastolic annular tissue velocities: a pilot study

BACKGROUND

Tissue Doppler imaging (TDI) of mitral (MA) and tricuspid annular (TA) events has been shown to describe systolic and diastolic properties of each respective ventricle. However, the effect of chronic elevations in pulmonary artery systolic pressure (PASP) on individual diastolic annular velocities has not been well characterized.

METHODS

Measurements of left (LV) and right ventricular (RV) performance and TDI of the lateral MA and TA to measure systolic and early and late diastolic velocities were recorded from 50 individuals (group I: mean age was 56 ± 15 years and mean PASP of 29 ± 6 mm Hg) and from 50 patients (group II: mean age was 55 ± 14 years and mean PASP of 83 ± 27 mm Hg).

RESULTS

Group II patients had worse parameters of RV performance whereas LV systolic function remained unaffected when compared with group I. Group II had lower TA early velocities (0.09 ± 0.04 m/sec versus 0.12 ± 0.03 m/sec; P < 0.0001) with higher late diastolic MA velocities (0.12 ± 0.04 m/sec versus 0.10 ± 0.03 m/sec; P < 0.002) than group I. MA late diastolic velocity (P < 0.02) was the most useful in identifying elevated PASP and early diastolic TA velocity (P < 0.01) in identifying abnormal right ventricular fractional area change.

CONCLUSION

Chronic pulmonary hypertension seems to selectively affect TDI annular diastolic velocities of both ventricles in different ways. Additional studies are needed to correlate changes in annular TDI velocities with symptoms and clinical outcomes in chronic pulmonary hypertension.

Differential strain and velocity generation along the right ventricular free wall in pulmonary hypertension

BACKGROUND

In contrast to the homogeneously distributed deformation properties within the left ventricle, the right ventricular (RV) free wall (RVFW) shows a more inhomogeneous distribution. It has been demonstrated that pulmonary hypertension (PH) results in significant RVFW mechanical delay.

OBJECTIVE

To assess the effect of the degree of pulmonary arterial systolic pressure on the RVFW strain gradient and on myocardial velocity generation.

METHODS

Peak longitudinal strain and velocity data were collected from three different segments (basal, mid- and apical) of the RVFW in 17 normal individuals and 31 PH patients.

RESULTS

A total of 144 RV wall segments were analyzed. RVFW strain values in individuals without PH were higher in the mid and apical segments than in the basal segment. In contrast, RVFW strain in PH patients was higher in basal segments and diminished toward the apex. In terms of RVFW velocities, both groups showed decremental values from basal to apical segments. Basal and mid-RVFW velocities were significantly lower in PH patients than in individuals without PH.

CONCLUSIONS

PH results in significant alterations of strain and velocity generation that occurs along the RVFW. Of these abnormalities, the reduction in strain from the mid and apical RVFW segments was most predictive of PH. It is important to be aware of these differences in strain generation when studying the effect of PH on the right ventricle. Additional studies are required to determine whether these differences are due to RV remodelling.

[Left ventricular diastolic dysfunction. Implications for anesthesia and critical care]

Over the last two decades there has been a growing recognition that cardiac function is not solely determined by systolic but also essentially by diastolic function. Left ventricular diastolic dysfunction is characterized by an impairment of ventricular filling caused either by abnormal relaxation, an active energy consuming process or decreased compliance, which is determined by passive tissue properties of the ventricle. Doppler echocardiography, including tissue Doppler imaging, has emerged as the preferred clinical tool for the assessment of left ventricular diastolic function. Recently the importance of left ventricular diastolic function is increasingly being recognized also during the perioperative period. Newer studies have shown that after cardiopulmonary bypass there is a significant decrease in left ventricular compliance. Experimental studies have demonstrated that sepsis is associated with a decrease in both active relaxation and ventricular compliance. Initial studies are also focusing on therapeutic options for patients with isolated diastolic dysfunction.

Left ventricular diastolic function evaluated with tissue Doppler imaging in children with familial Mediterranean fever

The aim of this study was to assess the left ventricular diastolic function using conventional echocardiography and tissue Doppler imaging in children with familial Mediterranean fever. This study included 29 (13 males and 16 females) patients and 30 healthy subjects as controls. Body mass index was calculated and arterial blood pressure was monitored. After an overnight fast, venous blood samples were taken and serum amyloid A protein, C-reactive protein, serum-fasting glucose, total cholesterol, triglycerides, high-density lipoprotein cholesterol, very low density lipoprotein cholesterol, and serum low-density lipoprotein cholesterol levels were measured. A complete 2-dimensional, M-mode, pulse wave Doppler, and pulse wave tissue Doppler echocardiographic examination was performed. There were no significant differences between the groups regarding age, body mass index values, systolic and diastolic blood pressures, heart rates, serum-fasting glucose, total cholesterol, triglycerides, high-density lipoprotein cholesterol, very low density lipoprotein cholesterol, and serum low-density lipoprotein cholesterol. Serum levels of inflammatory markers were higher in patients' group (C-reactive protein and serum amyloid A protein levels were 10.84 mg/dl, 22.32 mg/l in patients' group, respectively, and 4.11 mg/dl, 3.65 mg/l, respectively, in the healthy controls.) Peak mitral A wave, E and A wave ratio differed significantly in both groups. There were statistically significant differences regarding parameters observed by tissue Doppler imaging such as E'm, A'm, E'm, and A'm ratio between patients' group and controls. Tissue Doppler imaging provided additional information on left ventricular diastolic function. While systolic functions were in normal range, some of the diastolic function parameters were impaired in patients with familial Mediterranean fever during childhood.

Identifying right ventricular dysfunction with tissue Doppler imaging in pulmonary hypertension

BACKGROUND

Standard echocardiographic assessment of right ventricular (RV) function is problematic due to the complex RV geometry. We used tissue Doppler imaging to identify RV dysfunction in patients with pulmonary hypertension (PH).

METHODS

Study population consisted of 44 patients (mean age 52+/-11; 30 females) with PH who underwent color tissue Doppler imaging of the RV and right heart catheterization within 2 days of each other. Peak systolic velocity and strain were measured at the RV free wall and correlated with invasive measures of PH and RV function. Myocardial velocity and strain was also measured in 20 healthy volunteers who served as normal controls (mean age 47+/-13; 13 females).

RESULTS

PH patients had significantly reduced RV free wall velocity (6.4+/-2.1 cm/s vs. 8.2+/-2.1 cm/s; p<0.05) and RV strain (-18+/-7% vs. -28+/-6%; p<0.001) versus controls. RV peak strain demonstrated excellent correlation with transpulmonary gradient (r=0.72; p<0.001), pulmonary vascular resistance (r=0.73; p<0.001), and significant inverse correlation with cardiac index (r=-0.69; p<0.001). RV velocity had a significant, but weaker, correlation with cardiac index (r=0.33; p<0.05) and no association with transpulmonary gradient or pulmonary vascular resistance. In a multivariate model, RV strain but not RV velocity was independently associated with cardiac index.

CONCLUSIONS

RV myocardial strain demonstrated excellent correlation with hemodynamic variables indicative of RV performance in PH patients.

Utility of right ventricular tissue Doppler imaging: correlation with right heart catheterization

OBJECTIVES

The objective of this study was to correlate tissue Doppler imaging of the right ventricle (RV) with pulmonary hemodynamics in patients referred for right heart catheterization.

METHODS

Seventy subjects (mean age 54 +/- 13; 35 males) prospectively underwent tissue Doppler imaging of the RV and right heart catheterization within 1 day of each other. Peak systolic velocity and strain were measured at the RV free wall and correlated with pulmonary hemodynamics.

RESULTS

RV myocardial velocity demonstrated no correlation with any hemodynamic variable. While RV strain demonstrated significant correlation with cardiac index (r =-0.61; P < 0.001), correlations with transpulmonary gradient (r = 0.26; P < 0.05) and pulmonary vascular resistance (r = 0.30; P < 0.05) were weaker. Subgroup analysis revealed that in patients with left ventricular systolic dysfunction (n = 31), RV strain showed no correlation with any hemodynamic variable. In patients with normal left ventricular systolic function (n = 39), correlations were significant between RV strain and mean pulmonary artery pressure (r = 0.59; P < 0.001), pulmonary vascular resistance (r = 0.60; P < 0.001), and cardiac index (r =-0.67; P < 0.001).

CONCLUSIONS

RV myocardial strain correlates significantly with pulmonary hemodynamics in patients with pulmonary hypertension and normal left ventricular function. However, there is no correlation with RV performance in patients with left ventricular dysfunction.

Abnormal right ventricular myocardial strain generation in mild pulmonary hypertension

BACKGROUND

Although right ventricular (RV) dyssynchrony has been identified in patients with severe pulmonary hypertension due to significant RV enlargement and compromise in systolic function, a more clinically relevant question pertains to RV mechanical properties in patients with mild elevation in pulmonary artery systolic pressures (PASP).

METHODS

Several echocardiographic parameters and peak longitudinal strain were measured in 40 patients and divided into two groups of 20 patients based on their PASP.

RESULTS

Group I included 20 individuals (mean age 48 +/- 16 years with a mean PASP of 27 +/- 5 mmHg) and Group II included 20 patients (mean age 63 +/- 14 years with a mean PASP of 49 +/- 7 mmHg.) All time intervals were adjusted for heart rate. RV fractional area change and tricuspid annular plane systolic excursion for Group I (62 +/- 12% and 2.74 +/- 0.56 cm) and Group II (49 +/- 14%; P < 0.02 and 2.09 +/- 0.40; P < 0.002) were both normal. However, Group II had lower peak longitudinal RV free wall (RVF) strain (-27.3 +/- 7.1 % vs. -31.9 +/- 8.7%, P < 0.04), longer time to peak RVF strain (448 +/- 57 ms vs. 411 +/- 43 ms; P < 0.03) and evidence of significant RV dyssynchrony (-83 +/- 55 ms vs. 1 +/- 17 ms, P < 0.00001) in contrast to Group I.

CONCLUSION

In conclusion, mild elevations in PASP affect the mechanical properties of the RV and result in RV dyssynchrony despite absence of gross abnormalities in RV size or function.

Correlation of Tricuspid Annular Velocities With Invasive Hemodynamics in Pulmonary Hypertension

The authors performed tissue Doppler imaging of the tricuspid annulus in patients with pulmonary hypertension to assess its correlation with invasive indices of right ventricular function. The study population consisted of 32 patients with suspected pulmonary hypertension who underwent pulsed tissue Doppler imaging of the tricuspid annulus and right heart catheterization. Peak systolic (Sa), early diastolic (Ea), and late diastolic (Aa) velocities of the lateral tricuspid annulus were measured and correlated with hemodynamic variables. Peak Sa demonstrated excellent correlation with hemodynamic variables, including cardiac index (r=0.78; P<.001), pulmonary vascular resistance (r=-0.79; P<.001), and transpulmonary gradient (r=-0.72; P<.001). Peak Sa <10 cm/s predicted cardiac index <2.0 L/min/m2 with 89% sensitivity and 87% specificity. In conclusion, tissue Doppler imaging of the tricuspid annulus is a complementary method to assess right ventricular function in pulmonary hypertensive patients.

Right ventricular dyssynchrony in heart failure: a tissue Doppler imaging study

BACKGROUND

The development of right ventricular dysfunction is a poor prognostic sign in patients with heart failure (HF). Although left ventricular dyssynchrony has been well described, it is not known whether right ventricular dyssynchrony coexists in HF. We used tissue Doppler imaging to determine whether right ventricular dyssynchrony is also present in HF patients.

METHODS AND RESULTS

In 34 HF patients (mean age 56 +/- 13 years), we measured longitudinal strain at the right ventricular free wall, interventricular septum, and left ventricular lateral wall. Right ventricular and left ventricular dyssynchrony were defined as the difference in time to peak strain between the right ventricular free wall and the septum and between the left ventricular lateral wall and septum, respectively. Mean right ventricular dyssynchrony was 59 +/- 45 ms and the mean left ventricular dyssynchrony was 80 +/- 62 ms. We found a strong correlation between right ventricular dyssynchrony and pulmonary artery systolic pressure (r = 0.73; P < .001) and a negative correlation between right ventricular dyssynchrony and right ventricular fractional area change (r = -0.43; P < .02).

CONCLUSION

HF patients exhibit right ventricular dyssynchrony by strain imaging which correlates with pulmonary hypertension and right ventricular dysfunction.

Cardiac Contributions to Exercise Training Responses in Patients with Chronic Heart Failure: A Strain Imaging Study

The improvement of exercise capacity due to exercise training in heart failure has been associated with peripheral adaptation, but the contribution of cardiac responses is less clear. We sought the extent to which the improvement of functional capacity in patients undergoing exercise training for heart failure was related to myocardial performance. Thirty-seven patients (35 men, age 64 +/- 11) with symptomatic heart failure and left ventricular ejection fraction < or = 35% (29 +/- 9%) were studied during a 16-week exercise training program. LV function was assessed by resting and exercise 2D-echocardiography, tissue Doppler derived myocardial strain, and strain rate. Peak oxygen consumption (VO2) and LV function were measured at baseline and follow-up, and the contribution of LV function at baseline and its response to training to the change of each parameter was sought. Baseline peak VO2 (12.4 +/- 4.6) increased by 9% at 8 weeks (13.5 +/- 4.2, P = 0.26), and by 21% at 16 weeks (15.0 +/- 4.9, P < 0.001). Although there were no overall changes in myocardial parameters in this study, change in peak VO2 at 16 weeks was significantly correlated with baseline strain (r = 0.51, P = 0.003) and the improvement of strain at 8 weeks (r = 0.44, P = 0.01), independent of baseline functional capacity and clinical variables. Thus, change in peak VO2 following 16 weeks exercise training is related to myocardial function at baseline.

Doppler tissue imaging of the heart in secondary amyloidosis

Secondary amyloidosis (SA) affects cardiac texture and function by interstitial fibrosis. Doppler tissue imaging (DTI) may quantify heart function through the assessment of myocardial velocities. Echocardiographic findings of early cardiac amyloidosis (CA) without heart failure (HF) caused by SA were determined both by standard methods and DTI. It was then determined whether DTI is superior to conventional echocardiography in documenting early CA due to SA. Twenty-five patients with SA who had CA without HF (group 1) were compared with 25 healthy control subjects (group 2). After standard echocardiography, systolic (s), early (e) and late diastolic (a) velocities of interventricular septum, anterolateral, and anterior and inferior walls were measured from mitral annulus by DTI. The averages were called (s(mean)), (e(mean)), and (a(mean)), respectively. Fractional shortening (FS) and ejection fraction (EF) values of groups 1 and 2 were similar. Standard Doppler echocardiographic values were not typical for a specific diastolic abnormality. The (s(mean)) and (e(mean)) for group 1 were lower but (a(mean)) was higher compared with group 2 (all P < .05). The group 1 (e(mean)/a(mean)) was lower (P < .0001) and (E/e(mean)) was higher (P = .003) than in group 2 (both P < .05). (E/e(mean)) and (E/e(lateral wall)) ratios were positively correlated (r = 0.74, P < .05). In patients with early CA due to SA without HF, by DTI, (s(mean)) and (e(mean)) velocities decrease and (a(mean)) velocity increases. These may be markers of subclinical CA of SA when standard echocardiography is not informative. (E/e(mean)) ratio may be an alternative index to (E/e(lateral wall)).

Right ventricular dyssynchrony in patients with pulmonary hypertension is associated with disease severity and functional class

Background

Abnormalities in right ventricular function are known to occur in patients with pulmonary arterial hypertension.

Objective

Test the hypothesis that chronic elevation in pulmonary artery systolic pressure delays mechanical activation of the right ventricle, termed dyssynchrony, and is associated with both symptoms and right ventricular dysfunction.

Methods

Fifty-two patients (mean age 46 ± 15 years, 24 patients with chronic pulmonary hypertension) were prospectively evaluated using several echocardiographic parameters to assess right ventricular size and function. In addition, tissue Doppler imaging was also obtained to assess longitudinal strain of the right ventricular wall, interventricular septum, and lateral wall of the left ventricle and examined with regards to right ventricular size and function as well as clinical variables.

Results

In this study, patients with chronic pulmonary hypertension had statistically different right ventricular fractional area change (35 ± 13 percent), right ventricular end-systolic area (21 ± 10 cm²), right ventricular Myocardial Performance Index (0.72 ± 0.34), and Eccentricity Index (1.34 ± 0.37) than individuals without pulmonary hypertension (51 ± 5 percent, 9 ± 2 cm², 0.27 ± 0.09, and 0.97 ± 0.06, p < 0.005, respectively). Furthermore, peak longitudinal right ventricular wall strain in chronic pulmonary hypertension was also different -20.8 ± 9.0 percent versus -28.0 ± 4.1 percent, p < 0.01). Right ventricular dyssynchrony correlated very well with right ventricular end-systolic area (r = 0.79, p < 0.001) and Eccentricity Index (r = 0.83, p < 0.001). Furthermore, right ventricular dyssynchrony correlates with pulmonary hypertension severity index (p < 0.0001), World Health Organization class (p < 0.0001), and number of hospitalizations (p < 0.0001).

Conclusion

Lower peak longitudinal right ventricular wall strain and significantly delayed time-to-peak strain values, consistent with right ventricular dyssynchrony, were found in a small heterogeneous group of patients with chronic pulmonary hypertension when compared to individuals without pulmonary hypertension. Furthermore, right ventricular dyssynchrony was associated with disease severity and compromised functional class.

Relation of right ventricular free wall mechanical delay to right ventricular dysfunction as determined by tissue Doppler imaging

Several well-established echocardiographic parameters used in the assessment of right ventricular (RV) performance, as well as tissue Doppler imaging (TDI) to investigate RV free wall mechanical events, were prospectively obtained from a heterogenous group of 20 patients with varying degrees of pulmonary hypertension (mean age 51 +/- 13 years; World Health Organization class average 2.8, mean pulmonary systolic pressure 78 +/- 24 mm Hg) and compared with similar data retrospectively obtained from 20 healthy volunteers (mean age 45 +/- 15 years). Patients with varying degrees of pulmonary hypertension had worse RV performance parameters than healthy volunteers (RV fractional area change 37 +/- 13% vs 52 +/- 5%, p < 0.0001; RV myocardial performance index 0.76 +/- 0.31 vs 0.29 +/- 0.11, p < 0.0001; and eccentricity index 1.41 +/- 0.57 vs 0.98 +/- 0.06, p < 0.005). Similarly, in these patients with abnormal RV performance, TDI showed statistically significant smaller peak longitudinal RV free wall strain (-21.5 +/- 9.0% vs -28.0 +/- 4.1%, p < 0.01) and significantly delayed time to peak strain (459 +/- 76 vs 388 +/- 29 ms, p < 0.0005) values than in healthy volunteers; a very strong correlation between RV mechanical delay and RV fractional area change (r = -0.89) was noted.

Assessment of left ventricular diastolic function by Doppler tissue imaging in children with end-stage renal disease

AIM

To evaluate left ventricular (LV) diastolic function in children with end-stage renal disease (ESRD) using conventional pulsed-Doppler echocardiography and Doppler tissue imaging (DTI), and to compare the findings with these two modalities.

METHODS

Twenty-four children with ESRD and 22 healthy age- and sex-matched control subjects were assessed with conventional Doppler echocardiography and DTI. The scans of the renal disease patients were done after a dialysis session. Parameters related to LV systolic and diastolic function were compared in the ESRD and control groups.

RESULTS

The ESRD patients had lower mean mitral E/A ratio both according to conventional Doppler echocardiography and TDI than the control subjects. The ESRD group also had significantly longer isovolumetric relaxation time (116+/-31 ms vs 97+/-3.1 ms, respectively; p<0.001), and significantly longer deceleration time (235+/-44 ms vs 202+/-35 ms, respectively; p<0.01) than the control group.

CONCLUSION

DTI findings correlate well with conventional Doppler echocardiography findings. Children with ESRD show, after dialysis, echocardiographic signs of LV diastolic dysfunction.

Analysis of diastolic function in patients undergoing aortic aneurysm repair and impact on hemodynamic response to aortic cross-clamping

OBJECTIVES

The purpose of this study was to analyze left ventricular diastolic function in patients undergoing aortic aneurysm repair and to investigate the effects of laparotomy and aortic cross-clamping on diastolic function.

DESIGN

Prospective clinical study.

SETTING

University hospital.

PARTICIPANTS

Forty-five consecutive patients undergoing open aortic aneurysm repair.

INTERVENTIONS

Left ventricular diastolic function and hemodynamic variables were evaluated using transesophageal Doppler echocardiography and a pulmonary artery catheter at baseline, after laparotomy, and at 1 and 10 minutes after cross-clamping. Diastolic function was determined by Doppler derivatives of mitral inflow (E/A ratio, deceleration time of early inflow) and pulmonary venous flow (S/D ratio).

MEASUREMENTS AND MAIN RESULTS

Twenty of 39 patients revealed signs of diastolic dysfunction at baseline. Of these 20 patients, 14 displayed delayed relaxation and 6 displayed a pseudonormal filling pattern. Patients with pseudonormal filling exhibited a lower stroke volume (p = 0.02) and cardiac index (p < 0.01) in comparison to patients with normal diastolic function. Laparotomy was associated with an improvement of diastolic function in 9 of 20 patients with preexisting diastolic dysfunction. Only 3 patients suffered impairment of diastolic function after cross-clamping. The hemodynamic response to cross-clamping did not differ between patients with normal and abnormal diastolic function.

CONCLUSIONS

About 50% of patients undergoing aortic aneurysm repair exhibit signs of diastolic dysfunction. The majority of these patients showed delayed relaxation. Patients with pseudonormal filling displayed a significantly lower cardiac index. Laparotomy resulted in an improvement in diastolic function in about half of patients with preexisting diastolic dysfunction. The effects of cross-clamping on diastolic function are minimal.

Impact of left ventricular diastolic function on exercise capacity in patients with chronic mitral regurgitation: an exercise echocardiography study

BACKGROUND

Mitral regurgitation (MR) is known as one of the most frequent causes of heart failure and sudden death. In spite of increasing prevalence of MR, there have been no available data on cardiac determinants of exercise capacity in patients with chronic MR.

HYPOTHESIS

This study aimed to investigate cardiac determinants of exercise capacity in patients with chronic MR.

METHODS

We consecutively enrolled 32 patients (11 men, mean age: 44 +/- 14 years) who had greater than moderate MR with normal left ventricular (LV) systolic function (LV ejection fraction >50%). Conventional echocardiographic indices and parameters measured by Doppler tissue imaging at septal side of mitral annulus were obtained before exercise. Mitral regurgitation fraction, forward stroke volume, pulmonary venous flow velocities, and systolic pulmonary artery pressure (sPAP) were also obtained with standard methods.

RESULTS

Left ventricular ejection fraction was 61 +/- 6% and MR fraction was 48 +/- 13%. All patients finished a symptom-limited treadmill exercise test with a peak heart rate of >85% of predicted maximum heart rate. Mean exercise time was 9.95 +/- 2.17 min, corresponding to 11 +/- 2 metabolic equivalents. Among pre-exercise echocardiographic variables, only early diastolic mitral annulus velocity (E') and pulmonary venous reversal flow velocity (PVa) showed a significant correlation with exercise time (r = 0.44, p = 0.011, and r = -0.40, p = 0.040, respectively), which persisted after multivariate analysis (p = 0.011 and 0.038, respectively). Other parameters such as systolic mitral annulus velocity, resting and postexercise sPAP, forward stroke volume, LV size, LV ejection fraction, left atrial size, and regurgitant fraction showed no significant correlation.

CONCLUSIONS

Left ventricular diastolic function is an important determinant of exercise capacity in patients with chronic MR. Both E' and PVa, accepted surrogate estimates for LV diastolic function, may be useful for identifying patients with chronic MR and with poor exercise capacity.

Clinical in vivo calibration of pulse wave tissue Doppler velocities in the assessment of ventricular wall motion. A comparison study with M-mode echocardiography

BACKGROUND

Pulsed Wave Tissue Doppler (PWTD) recording of myocardial velocities has been widely used for assessing ventricular function but the output trace has finite thickness that leads to potential ambiguity in determining velocity and timing.

OBJECTIVE

To determine optimal method of measurement of PWTD traces by comparing them with those obtained from digitised M-mode recorded from the atrioventricular (AV) valve ring (septal, LV and RV free wall).

METHODS

We studied 100 subjects, 49 normal and 51 with coronary artery disease (15 patients with reduced left ventricular wall motion, mean systolic amplitude of LV free wall 0.8+/-0.3 cm), mean age 53+/-15 years. We recorded AV ring motion using PWTD and M-mode echo techniques. PWTD velocity signals were measured separately at: outer, inner and mid-points of the envelope and compared with peak velocities obtained from digitised M-mode long axis.

RESULTS

Peak systolic (S), early diastolic (E) and late diastolic (A) PWTD velocities at outer, inner and middle envelope correlated closely with the corresponding M-mode measurements at left, septal and right ventricular free wall. However, only the midpoint S and E wave PWTD signal velocities agreed numerically with those obtained by digitised M-mode velocities; S (left 6.56+/-1.80 vs. 6.54+/-1.91 cm/s N.S.); E (left 8.50+/-3.25 vs. 7.65+/-3.30 cm/s N.S.). Agreement was somewhat less satisfactory for A wave; left 7.40+/-2.13 vs. 6.23+/-2.09 cm/s p<0.05.

CONCLUSION

Atrioventricular valve ring echo provides an excellent in vivo calibration model for validating tissue Doppler velocity estimates. Since the mid-point of the envelope of the tissue Doppler signal is the most closely related value to that of the digitised M-mode, it may be recommended as a convention for routine practice.

Determinants of functional capacity in patients with chronic heart failure: role of filling pressure and systolic and diastolic function

BACKGROUND

Previous work suggesting a better correlation of diastolic than systolic function with exercise capacity in heart failure may reflect the relative insensitivity and load-dependence of ejection fraction (EF). We sought the correlation of new and more sensitive methods of quantifying systolic and diastolic function and filling pressure with functional capacity.

METHODS

We studied 155 consecutive exercise tests on 95 patients with congestive heart failure (81 male, aged 62 +/- 10 years), who underwent resting 2-dimensional echocardiography and tissue Doppler imaging before and after measurement of maximum oxygen uptake (peak VO2).

RESULTS

The resting EF was 31% +/- 10% and a peak VO2 was 13 +/- 5 mL/kg.min; the majority of these patients (80%) had an ischemic cardiomyopathy. Resting EF (r = 0.14, P = .09) correlated poorly with peak VO2 and mean systolic (r = 0.23, P = .004) and diastolic tissue velocities (r = 0.18, P = .02). Peak EF was weakly correlated with the mean systolic (r = 0.18, P = .02) and diastolic velocities (r = 0.16, P < .04). The mean sum of systolic and diastolic velocities in both annuli (r = 0.30, P < .001) and E/Ea ratio (r = -0.31, P < .001) were better correlated with peak VO2 . Prediction of peak VO2 was similar with models based on models of filling pressure (R = 0.61), systolic factors (R = 0.63), and diastolic factors (R = 0.59), although a composite model of filling pressure, systolic and diastolic function was a superior predictor of peak VO2 (R = 0.69; all P < .001).

CONCLUSIONS

The reported association of diastolic rather than systolic function with functional capacity may have reflected the limitations of EF. Functional capacity appears related not only to diastolic function, but also to systolic function and filling pressure, and is most closely associated with a combination of these factors.

Detection of a pseudonormal mitral inflow pattern: an echocardiographic and tissue Doppler study

OBJECTIVE

The aim of this study was to assess the ability of several echocardiographic and tissue Doppler imaging (TDI) derived parameters to improve the noninvasive diagnosis of a pseudonormal mitral inflow pattern.

METHODS

Ninety-eight consecutive patients with age-related normal transmitral Doppler profile underwent echocardiography including TDI and measurement of left ventricular end-diastolic pressure (LVEDP) using fluid-filled catheters. Peak transmitral velocities were determined at rest (E, A) and during the strain phase of a Valsalva maneuver. The difference in duration between the pulmonary venous retrograde velocity and the transmitral A-velocity (PVR-A) was calculated from pulsed Doppler recordings. Propagation velocity of the early mitral inflow (VP) was determined by color M-mode. Early diastolic peak mitral annulus velocities (E') and the early diastolic transmyocardial velocity gradient of the posterior basal wall (MVG) were obtained by TDI.

RESULTS

Fifty-two patients presented with normal diastolic function (group I: LVEDP9.5 +/- 3 mm Hg, E/A1.1 +/- 0.19), while pseudonormalization, defined as LVEDP 15 mm Hg and E/A > 0.9, was found in 46 patients (group II: LVEDP23 +/- 7 mm Hg, E/A1.43 +/- 0.83). The coefficient of linear correlation (r) and the area under ROC - curve (AUC) to predict LVEDP values 15 mm Hg were maximal for the index PVR-A (AUC = 0.92, r = 0.77), followed byE/E' (AUC = 0.80, r = 0.46), MVG (AUC = 0.65, r = 0.33) and E/VP (AUC = 0.69, r = 0.30), P < 0.01, whereas the decrease in E/A ratio during Valsalva maneuver failed to reach significance. Similar results were observed when echocardiographic parameters were used to estimate the left ventricular diastolic pressure before atrial contraction.

CONCLUSIONS

PVR-A enabled the most accurate estimation of LVEDP. TDI-derived indices E/E' and MVG are also reliable alternatives superior to the classical Valsalva maneuver to detect a pseudonormal transmitral Doppler profile.

Left ventricular diastolic function assessment by tissue Doppler echocardiography in relation to hormonal replacement therapy in postmenopausal women with diastolic dysfunction

The objective of this study was to evaluate the effect of hormone replacement therapy (HRT) regimens on left ventricular diastolic function by using mitral pulsed wave Doppler (MPWD) and tissue Doppler velocities (TDE). Seventy-eight postmenopausal women with normotensive and impaired diastolic left ventricular filling were included in the study. All the patients began a six-cycle HRT course. This formulation consisted of E2 valerate plus Medroxy progesterone acetate (MPA). Left ventricular diastolic function at rest was evaluated by M-mode, two-dimensional, MPWD and TDE in 78 postmenopausal women with normal blood pressure before the treatment for 6 months of HRT. The M-mode, two-dimensional, and MPWD parameters assessed were heart rate, systolic blood pressure, diastolic blood pressure, left ventricular mass index, ejection fraction of the left ventricle (EF), septal (IVS) and posterior wall (PW) thickness, left ventricular end-systolic (LVESD) and end-diastolic (LVEDD) diameter, left atrial diameter, peak early diastolic velocity (E), peak atrial velocity (A), E/A ratio, E acceleration time, E deceleration time, diastolic filling period, and isovolumic relaxation time (IVRT). The TDE parameters assessed were peak early diastolic velocity (E'), peak late diastolic velocity (A'), peak systolic velocity, E'/A' ratio, E' acceleration time, E' deceleration time, IVRT', and E/E' ratio. Quantitative data were analyzed using Student t test. Among the MPWD parameters, peak A velocity, E deceleration time, and IVRT significantly decreased, while peak E velocity and E/A ratio increased after a 6-month treatment. From the point of TDE parameters, E' velocity and E'/A' ratio increased, while A' velocity, E' deceleration time, E/E' ratio and IVRT' decreased. Some MPWD and TDE parameters were partially reversed after HRT. TDE velocities and especially E/E' ratio may provide better and true information of the diastolic function. TDE parameters were independent from the preload and did not produce pseudonormal pattern. HRT may cause increase in the blood volume and produce pseudonormal pattern in transmitral flow. In that case, TDE may be a beneficial method for evaluation of diastolic function.