Association between myocardial right ventricular relaxation time and pulmonary arterial pressure in chronic obstructive lung disease: analysis by pulsed Doppler tissue imaging

Group 3 Pulmonary Hypertension: From Bench to Bedside

Pulmonary hypertension (PH) because of chronic lung disease is categorized as Group 3 PH in the most recent classification system. Prevalence of these diseases is increasing over time, creating a growing need for effective therapeutic options. Recent approval of the first pulmonary arterial hypertension therapy for the treatment of Group 3 PH related to interstitial lung disease represents an encouraging advancement. This review focuses on molecular mechanisms contributing to pulmonary vasculopathy in chronic hypoxia, the pathology and epidemiology of Group 3 PH, the right ventricular dysfunction observed in this population and clinical trial data that inform the use of pulmonary vasodilators in Group 3 PH.

Differences in the microcirculation disturbance in the right and left ventricles of neonatal rats with hypoxic pulmonary hypertension

Microcirculation disturbance is a crucial pathological basis of heart damage; however, microcirculation alterations induced by hypoxic pulmonary hypertension (HPH) remain unknown, and the left ventricle (LV) in HPH is conventionally ignored. Herein, we investigated the changes in the cardiac structure, function and microcirculation after HPH and further compared the differences between the right ventricle (RV) and LV. Using a neonatal rat model of HPH, we found RV myocardial hypertrophy, dysfunction and poor myocardial perfusion in HPH rats. Additionally, RV microcirculation disturbance manifested as the abnormal expression of endothelin-1/eNOS and increased expression of intercellular cell adhesion molecule-1 (ICAM-1) or E-selectin 3 days after hypoxia, followed by vascular inflammation, coronary arterial remodeling and microvascular sparseness. Impairment in LV vasodilation was detected in rats after 3 days of hypoxia; however, no obvious microvascular rarefaction or inflammatory reaction was observed in the LV. In conclusion, our results suggest that HPH mainly triggers RV microcirculation disturbances, causing low myocardial perfusion damage and cardiac dysfunction. Despite the differences in the RV and LV, their impaired microvascular function, mediated by endothelial cells, occurs almost simultaneously after HPH, earlier than cardiac functional or structural abnormalities.

The Dark Side of the Moon: The Right Ventricle

The aim of this review article is to summarize current knowledge of the pathophysiology underlying right ventricular failure (RVF), focusing, in particular, on right ventricular assessment and prognosis. The right ventricle (RV) can tolerate volume overload well, but is not able to sustain pressure overload. Right ventricular hypertrophy (RVH), as a response to increased afterload, can be adaptive or maladaptive. The easiest and most common way to assess the RV is by two-dimensional (2D) trans-thoracic echocardiography measuring surrogate indexes, such as tricuspid annular plane systolic excursion (TAPSE), fractional area change (FAC), and tissue Doppler velocity of the lateral aspect of the tricuspid valvular plane. However, both volumes and function are better estimated by 3D echocardiography and cardiac magnetic resonance (CMR). The prognostic role of the RV in heart failure (HF), pulmonary hypertension (PH), acute myocardial infarction (AMI), and cardiac surgery has been overlooked for many years. However, several recent studies have placed much greater importance on the RV in prognostic assessments. In conclusion, RV dimensions and function should be routinely assessed in cardiovascular disease, as RVF has a significant impact on disease prognosis. In the presence of RVF, different therapeutic approaches, either pharmacological or surgical, may be beneficial.

The impact of age and gender on right ventricular diastolic function among healthy adults

BACKGROUND

Doppler echocardiography is ideally suited for assessment of diastolic function, being widely available, non-invasive, and less expensive than other techniques. However, data regarding age- and gender-matched reference values of right ventricular diastolic function are limited. This study aims to explore the physiologic variations of right ventricle (RV) diastolic function in a large cohort of healthy adults, and to investigate clinical and echocardiographic correlates.

METHODS

From June 2007 to February 2014, 1168 healthy Caucasian subjects [mean age 45.1±15.6 years, range 16-92; 555 (47.5%) men] underwent comprehensive transthoracic echocardiography (TTE) following current guidelines. The following RV main diastolic measurements were measured: peak early inflow velocity (E), annular both early (e') and atrial (a') velocities, E/e' ratio.

RESULTS

RV E/e' constantly increases with age in females, but do not change substantially in males. RV E/A constantly decreases with age in both genders. Stepwise multiple linear regression analysis underlined a close significant association of RV diastolic function with both right and left heart morphologic measurements (right atrial area, RV diameters, left atrial volume) and functional indexes (TAPSE, RV tissue Doppler peak systolic velocity, left ventricular E/Ee'), as well as with indexes of increased pulmonary resistance.

CONCLUSION

Our data highlight the potential usefulness of different normal reference values according to the age and gender to correctly evaluate RV diastolic function. Differences in terms of demographic and anthropometric parameters could be useful to avoid potential misclassification of RV diastolic function when based on dichotomously suggested normal cut-off values.

Assessment of myocardial function in preterm infants with chronic lung disease using tissue Doppler imaging

OBJECTIVES

To assess myocardial function and presence of pulmonary hypertension (PH) using both tissue Doppler imaging (TDI) and conventional echocardiography in preterm infants of <32 weeks gestation with chronic lung disease (CLD).

DESIGN

Prospective observational study.

SETTING

Tertiary neonatal intensive care unit.

PATIENTS

Three groups of preterm infants were recruited. Group 1-CLD receiving positive pressure airway support including high-flow humidified nasal cannula oxygen (n=25), group 2-CLD receiving low-flow nasal oxygen (n=25) and group 3-no CLD (n=22).

METHODS

Echocardiography was performed around 36 weeks corrected gestational age. Myocardial function and PH were assessed using both conventional (left ventricular fractional shortening (LVFS) and left ventricular output (LVO), tricuspid regurgitation and ventricular septal flattening) and TDI techniques (myocardial velocities, myocardial performance index (MPI) and right ventricular isovolumetric relaxation time (RV-IVRT)).

RESULTS

The MPI of right ventricle (RV) and left ventricle (LV) was significantly higher in CLD infants: mean RV MPI group 1-0.79, group 2-0.65 and group3-0.52. LV MPI: group 1-0.77, group 2-0.70 and group 3-0.45. There was a trend towards higher MPIs in group 1 compared with group 2. LVFS and LVO were similar across all three groups. RV-IVRT was also significantly higher in infants with CLD infants (group 1-64 milliseconds, group 2-62 milliseconds and group 3-52 milliseconds). PH was not detected by conventional echocardiography.

CONCLUSIONS

Infants with CLD have evidence of relative biventricular dysfunction and higher pulmonary arterial blood pressure as demonstrated by TDI, which were not detected by conventional echocardiography.

RV diastolic dysfunction: time to re-evaluate its importance in heart failure

Right ventricular (RV) diastolic dysfunction was first reported as an indicator for the assessment of ventricular dysfunction in heart failure a little over two decades ago. However, the underlying mechanisms and precise role of RV diastolic dysfunction in heart failure remain poorly described. Complexities in the structure and function of the RV make the detailed assessment of the contractile performance challenging when compared to its left ventricular (LV) counterpart. LV dysfunction is known to directly affect patient outcome in heart failure. As such, the focus has therefore been on LV function. Nevertheless, a strategy for the diagnosis and assessment of RV diastolic dysfunction has not been established. Here, we review the different causal mechanisms underlying RV diastolic dysfunction, summarising the current assessment techniques used in a clinical environment. Finally, we explore the role of load-independent indices of RV contractility, derived from the conductance technique, to fully interrogate the RV and expand our knowledge and understanding of RV diastolic dysfunction. Accurate assessment of RV contractility may yield further important prognostic information that will benefit patients with diastolic heart failure.

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.

Assessment of ventricular functions by tissue Doppler echocardiography in children with asthma

Patients with asthma develop pulmonary hypertension due to recurrent hypoxia and chronic inflammation, leading to right heart enlargement with ventricular hypertrophy. Patients with severe asthma can experience cor pulmonale later in life, but little is known about ventricular function during the early stages of the disease. This study aimed to investigate ventricular functions in asymptomatic children with asthma as detected by conventional echocardiography and tissue Doppler echocardiography (TDE). Fifty-one pediatric patients (mean age 10.4 ± 2.2 years) with asthma and 46 age- and sex-matched healthy children (mean age 10.9 ± 2.4 years) were studied. All subjects were examined by conventional echocardiography and TDE, and they had pulmonary function tests on spirometry. The right-ventricular (RV) wall was statistically (p = 0.01) thicker among asthmatic patients (4.7 ± 1.5 mm) compared with healthy children (3.6 ± 0.4 mm). However, conventional pulsed-Doppler indices of both ventricles did not differ significantly between asthmatic patients and healthy children (p > 0.05). The results of TDE examining RV diastolic function showed that annular peak velocity during early diastole (E'), annular peak velocity during late diastole (A') (16.4 ± 1.8 and 5.1 ± 1.4 cm/s, respectively), E'/A' ratio (3.2 ± 0.7), isovolumetric relaxation time (67.7 ± 10.2 ms) and myocardial performance index (48.1 % ± 7.0 %) of the lateral tricuspid annulus among asthmatic patients differed significantly (p = 0.01) from those of healthy children (13.2 ± 2.3, 8.2 ± 2.0 cm/s, 1.6 ± 0.5, 46.2 ± 8.7 ms, and 42.0 % ± 5.7 %, respectively). Only peak expiratory flow (PEF) rate from the pulmonary function tests was negatively correlated with the E'/A' ratio of the tricuspid annulus (r = -0.38, p = 0.01). This study showed that although the findings of clinical and conventional echocardiography were apparently normal in children with asthma, TDE showed subclinical dysfunction of the right ventricle, which is negatively correlated with PEF. These findings signify the diagnostic value of TDE in the early detection and monitoring of such deleterious effects among asthmatic patients.

Validation of the isovolumetric relaxation time for the estimation of pulmonary systolic arterial blood pressure in chronic pulmonary hypertension

AIMS

Transthoracic echocardiography is a useful technique for non-invasive detection of pulmonary arterial systolic pressure (PASP). Isovolumic relaxation time (IVRT) measured by Doppler tissue imaging (DTI) is a sensitive measurement of changes in pulmonary vasculature. Our aim was to validate IVRT in the echocardiographic assessment of pulmonary hypertension (PH) patients.

METHODS AND RESULTS

We studied 196 PH patients (67% women, mean age 51.8 ± 16.6 years, mean PASP: 81 ± 24 mmHg) and 37 consecutive age- and sex-matched controls (58% women, mean age 44.7 ± 16.4 years, mean PASP 27.7 ± 5.5 mmHg). The estimation of PASP was derived from tricuspid regurgitation velocity according to the Bernoulli equation. The measurement of IVRT was calculated using pulsed tissue Doppler. In the PH group and in the healthy volunteers group (P < 0.0001), the average IVRT was 113.4 ± 28.5 ms [95% confidence interval (CI): 109-117] and 41 ± 12.5 ms (95% CI: 37-45), respectively. We found a strong correlation between IVRT and systolic pulmonary pressure in the PH group (r = 0.52, P < 0.0001) and a cut-off of 75 ms showed a sensitivity and specificity of 94% and 97%, respectively, for the prediction of elevated PASP.

CONCLUSION

The determination of IVRT by DTI is a simple and reproducible method that correlates well with PASP. It is, therefore, a parameter to consider in the echocardiographic assessment of patients with PH, and may be particularly important when the tricuspid Doppler signal is poor.

Right ventricular dysfunction in chronic lung disease

Right ventricular (RV) dysfunction arises in chronic lung disease when chronic hypoxemia and disruption of pulmonary vascular beds increase ventricular afterload. RV dysfunction is defined by hypertrophy with preserved myocardial contractility and cardiac output. RV hypertrophy seems to be a common complication of chronic and advanced lung disease. RV failure is rare, except during acute exacerbations of chronic lung disease or when multiple comorbidities are present. Treatment is targeted at correcting hypoxia and improving pulmonary gas exchange and mechanics. There are no data supporting the use of pulmonary hypertension-specific therapies for patients with RV dysfunction secondary to chronic lung disease.

Clinical asthma phenotypes: is there an impact on myocardial performance?

BACKGROUND

Asthma is a systemic disease, which affects various body systems. We aimed to assess the impact of clinical asthma phenotypes on myocardial performance in asthmatic children using tissue Doppler imaging (TDI).

METHODS

We enrolled 58 children with moderate persistent asthma and 62 age- and sex-matched healthy controls. Asthmatic children were classified according to clinical asthma phenotypes into shortness of breath group (n = 26) and wheezy group (n = 32). Pulmonary function tests, and conventional and TDI echocardiography were performed.

RESULTS

TDI echocardiography assessment of the studied groups showed that asthmatic children as a group had significant left and right ventricular dysfunction when compared with healthy controls. Children in the shortness of breath group had a significant diastolic dysfunction of both ventricles in the form of lower tricuspid and mitral annular early myocardial diastolic velocity (Em), early to late myocardial diastolic velocity (Em/Am) ratio, and prolonged isovolumetric relaxation time when compared with wheezy group (P < 0.001). In the shortness of breath group, TDI-derived myocardial performance index (MPI) of both ventricles was significantly higher when compared with wheezy group (P < 0.001) reflecting global myocardial dysfunction. Conventional echocardiography of both ventricles showed RV diastolic dysfunction in the form of a significantly lower tricuspid E/A ratio in the shortness of breath group when compared with wheezy group.

CONCLUSION

Clinical asthma phenotypes have an impact on myocardial function especially those presented with shortness of breath. Thus, measurement of MPI by TDI can detect subclinical changes in the cardiac performance in asthmatic children.

Predicting mortality and hospital admission in patients with COPD: significance of NT pro-BNP, clinical and echocardiographic assessment

AIMS

To quantify the ability of N-terminal pro-brain natriuretic peptide (NT pro-BNP) to predict mortality and hospitalization in patients with chronic obstructive airways disease (COPD).

METHODS

Prospective single-centre observational study of 140 consecutive patients aged at least 18 years with COPD between 27 March 2004 and 28 February 2008 (median follow-up 3.9 years).

RESULTS

Sixty-five (46%) men, 26 (19%) O2 therapy, 115 (82%) smokers, 38 (27%) patients receiving diuretics, 15 (11%) left-ventricular ejection fraction less than 45%. Median [interquartile range (IQR)] NT pro-BNP concentration 16.2 (25.4) pmol/l. NT pro-BNP was higher in those with a dilated left atrium (P<0.001), aortic stenosis (P=0.02), left-ventricular systolic dysfunction (P=0.027), right ventricular impairment (P=0.011), atrial fibrillation (P<0.001), patients receiving diuretics (P=0.010) and angiotensin-converting enzyme (ACE) inhibitors (P=0.006). One-year mortality and hospitalization rates were 2.9 and 25.4%. The median (IQR) time to hospitalization and length of first hospital stay: 383.5 (605) and 4.0 (7.0) days. NT pro-BNP was an excellent discriminator of right-ventricular impairment (C statistic=0.90) and predicted survival (highest quartile versus lowest quartile relative risk=3.02, P=0.001), but not hospital admission. After adjustment this association was not significant.

CONCLUSION

NT pro-BNP predicts survival, but not hospital admission in patients with COPD. The ability of NT pro-BNP to independently predict death or hospitalization is superseded by the presence of a dilated left atrium, aortic stenosis and left-ventricular systolic dysfunction.

Computed tomography and magnetic resonance imaging of pulmonary hypertension: Pulmonary vessels and right ventricle

Pulmonary hypertension (PH) is very heterogeneous and the classification identifies five major groups including many associated disease processes. The treatment of PH depends on the underlying cause and accurate classification is paramount. A comprehensive assessment to identify the cause and severity of PH is therefore needed. Furthermore, follow-up assessments are required to monitor changes in disease status and response to therapy. Traditionally, the diagnostic imaging work-up of PH comprised mainly echocardiography, invasive right heart catheterization, and ventilation/perfusion scintigraphy. Due to technical advances, multidetector row computed tomography (CT) and magnetic resonance imaging (MRI) have become important and complementary investigations in the evaluation of patients with suspected PH. Both modalities are reviewed and recommendations for clinical use are given.

Left and right ventricular systolic long-axis function and diastolic function in patients with takotsubo cardiomyopathy

AIMS

  Takotsubo cardiomyopathy is characterized by apical wall motion abnormalities without coronary stenosis. Limited information is available on the genesis of the underlying reversible contractile disorder. Our objective in this prospective study was to investigate biventricular changes in systolic long-axis function and diastolic parameters in the acute phase and after recovery.

METHODS AND RESULTS

  Thirteen consecutive patients were examined by echocardiography and coronary angiography at admission and again by echocardiography after 3 months. Amplitudes, systolic and diastolic velocities of the mitral and tricuspid annuli and conventional diastolic parameters were measured. Systolic long-axis shortening of the left ventricle (LV) and right ventricle (RV) improved from 9.6 ± 2.2 mm to 11.2 ± 1.9 mm (P = 0.02) and from 21.3 ± 3.6 mm to 24.1 ± 2.8 mm (P = 0·02), respectively. LV systolic, early and late diastolic velocities measured by pulsed-wave tissue Doppler also improved, while additional conventional diastolic parameters of the LV and RV diastolic function were unchanged.

CONCLUSIONS

  Takotsubo cardiomyopathy temporarily affects systolic LV and RV function, while most diastolic parameters remain unchanged.

Imaging techniques and the evaluation of the right heart and the pulmonary circulation

Since the right side of the heart and the pulmonary circulation are regarded as secondary components of the circulatory system, their role in disease has traditionally not received the same attention as their counterparts in the systemic circulation. This was partly because precise noninvasive study of these structures was difficult. For many years, chest radiography and invasive angiography were the only techniques available for imaging the minor circulation. The development of transthoracic echocardiography and nuclear techniques has produced a significant leap forward for noninvasive imaging, particularly of the right ventricle. More recently, novel echocardiographic techniques, and advances in computed tomography and magnetic resonance imaging, in particular, have expanded our diagnostic armamentarium and provided new insights into the anatomy and function of the pulmonary circulation in both health and disease. This article contains a review of the current status of techniques for imaging the right side of the heart and the pulmonary circulation.

Isovolumetric relaxation time of the right ventricle assessed by tissue Doppler imaging

OBJECTIVES

The isovolumetric relaxation time of the right ventricle (RV-IVRT) can be assessed using a method based on ECG and pulsed wave Doppler (PW). Recently pulsed wave Doppler tissue imaging (PW-DTI) has been introduced in the assessment.

DESIGN

RV-IVRT obtained by the two methods was compared in 20 consecutive patients as was the time from the R wave on the ECG to the onset of tricuspid flow (R-T), to the closure of the pulmonic valve (R-P), to the onset of early diastolic motion of the tricuspid annulus tissue (R-E) and to the end of the systolic motion (R-S).

RESULTS

RV-IVRT obtained by the PW method was significantly (p < 0.001) shorter than RV-IVRT obtained by PW-DTI. R-S had significantly (p < 0.001) shorter duration than R-P, while there was no significant difference between R-E and R-T.

CONCLUSIONS

The methods are not measuring the same interval. Only the PW method measures RV-IVRT according to the usual definition. Different reference values have to be used if the methods are used in the assessment of RV diastolic function.

Non-invasive investigations of the right heart: how and why?

The importance of right ventricular (RV) function in the clinical management of patients with cardiopulmonary disorders is now well recognized. However, due to both its shape and location and to the load dependence of its ejection fraction, accurate evaluation of its function is still a challenge. Echocardiography allows morphological, hemodynamic and functional assessment of the right heart. Displacement and deformation parameters derived from new techniques are promising tools. 3D echocardiography also has a potential interest in the quantification of RV volumes and ejection fraction. Radionuclide technique allows an easy and accurate measurement of right ventricular ejection fraction. MRI remains nowadays the technique of choice for the quantification of volumes and function of the RV. All these techniques have proven their interest in various diseases affecting the right heart. RV function is an important prognostic factor in heart failure and is a major component of functional capacity in such patients. In pulmonary arterial hypertension, echocardiography is the best tool for the routine follow-up of patients. Finally, all these non-invasive techniques of investigation of the right heart enable the diagnosis of specific right ventricular damage such as myocardial infarction or arrhythmogenic right ventricular dysplasia.

Tissue Doppler and strain imaging: anything left in the echo-lab?

Medline research indicates that an increasing number of manuscripts have been published in the last decade claiming, the feasibility and the potential clinical role of tissue Doppler and strain/strain rate imaging. However, despite this amount of scientific evidence, these technologies are still confined to dedicated, high-tech, research-oriented echocardiography laboratories. In this review we have critically evaluated these techniques, analysing their physical principles, the technical problems related to their current clinical application, and the future perspectives. Finally, this review explores the reasons why these technologies are still defined "new technologies" and the impact of their implementation on the current clinical activity of an echocardiography laboratory.

Myocardial tissue Doppler changes in patients with bronchopulmonary dysplasia

OBJECTIVE

To determine whether tissue Doppler measurements provide sensitive measures of right ventricular function that correlate with the severity of bronchopulmonary dysplasia (BPD).

STUDY DESIGN

21 subjects (6 control subjects with no/mild BPD, 7 patients with moderate BPD, and 8 patients with severe BPD) underwent limited echocardiograms with standard M-mode, mitral and tricuspid inflow velocities, and tissue Doppler features measured. BPD severity was scored by using the NICHD/NHLBI/ORD workshop rating scale by physicians blinded to the echocardiogram results. Groups were compared by using 1-way analysis of variance with post-hoc testing and linear regression.

RESULTS

Patients with moderate BPD had a higher early Doppler inflow velocity to the early tissue Doppler velocity ratio (E/E' ratio; P = .03), corresponding to increased end diastolic pressure, compared with patients with no/mild BPD. Patients with severe BPD had a higher E/E' ratio (P = .004) than patients with no/mild BPD. Linear regression demonstrated a correlation between BPD category and right ventricle E/E' (P = .007, R(2) = 0.33) and left ventricular myocardial performance index (P = .02, R(2) = 0.28).

CONCLUSION

Increasing right ventricle E/E' ratio correlates with clinical severity of BPD. Abnormal left ventricular myocardial performance index was noted to correlate with the grade of BPD. Further longitudinal studies of tissue Doppler echocardiographic assessment of cardiac function in premature infants with BPD are needed.

Myocardial tissue Doppler-based indexes to distinguish right ventricular volume overload from right ventricular pressure overload

The objective of this study was to develop tissue Doppler parameters that could be used to differentiate right ventricular (RV) volume overload from RV pressure overload. The RV-pressure-overload group consisted of 40 patients with severe pulmonary hypertension, and the RV-volume-overload group consisted of 40 patients who had an atrial septal defect without evidence of right-to-left shunt, significant pulmonary hypertension, or Eisenmenger's complex. Another 40 healthy subjects were enrolled and served as a control group. Routine echocardiography and tissue Doppler imaging were performed. RV myocardial performance index was determined based on data collected during tissue Doppler imaging over the lateral tricuspid annulus. In patients with RV pressure overload, tissue Doppler parameters showed characteristically lower systolic velocity over the tricuspid annulus (RV myocardial systolic wave [Sm]) and longer isovolumic relaxation time (RV-IVRT). Nevertheless, in patients with RV volume overload, RV-Sm increased significantly, but early-diastolic velocity over tricuspid annulus was relatively low. In conclusion, RV-MPI, RV-Sm/early-diastolic velocity over tricuspid annulus, and RV-IVRT/RV-Sm were all useful to differentiate RV pressure overload from volume overload, although RV-IVRT/RV-Sm was the best parameter, with excellent sensitivity and specificity.

Tissue Doppler echocardiographic assessment of cardiac function in children with bronchial asthma

BACKGROUND

The aim of the present study was to evaluate the role of tissue Doppler echocardiography in assessment of ventricular function in pediatric patients with bronchial asthma (BA).

PATIENTS AND METHODS

Fifty-one pediatric patients with BA and 30 age- and sex-matched healthy subjects were studied. BA patients were divided into two groups: mild BA (n = 33) and moderate to severe BA (n = 18). All subjects were examined on conventional and tissue Doppler echocardiography, and 44 patients had pulmonary function tests on spirometry within 1 week of echocardiographic examination.

RESULTS

Conventional echocardiographic parameters were all similar in mild asthmatic patients and control subjects. Tricuspid E velocity, E/A ratio and isovolumetric relaxation time (IVRT) in moderate and severe cases differed significantly from mild cases and control subjects. E', A', E'/A' ratio and IVRT of the lateral tricuspid annulus, and IVRT of the medial and lateral mitral annuli were different between mild cases and control subjects. E' velocity and IVRT of the lateral tricuspid annulus and IVRT of the medial and lateral mitral annuli were also different between mild cases and moderate to severe cases. Pulmonary function tests correlated well with E', E'/A' and IVRT of lateral tricuspid annulus.

CONCLUSION

Patients with BA have subclinical right ventricular diastolic dysfunction even in the early stages. The severity of the functional impairment is parallel with the severity of the disease. Tissue Doppler echocardiography has a greater predictive value than conventional imaging, and is useful for evaluating ventricular function in patients with BA.

Imaging of the heart in pulmonary hypertension

Pulmonary hypertension (PH) is a disease of the pulmonary arteries resulting in a progressive increase in pulmonary vascular resistance, ultimately leading to right ventricular failure and death. It is a rare disease with a poor prognosis. The functional capacity of the right ventricle (RV) is a major prognostic determinant in PH. Our understanding of RV performance in PH has been hindered by the lack of techniques that give a reliable picture of right ventricular morphology and function. There have been recent major advances in our understanding of the mechanism of disease development, in the diagnostic process and in the treatment of PH. There are now three classes of medications that are effective in the treatment of PH: prostanoids, endothelin receptor antagonists and phosphodiesterase-5 inhibitors. Therapeutic advances in the management of PH have reinforced the requirement for non-invasive, accurate and reproducible methods of assessment to act as 'end-points' to measure the effects of treatment. It is our opinion that the most useful 'end-point' would be one that evaluates right heart morphology and function. We introduce and discuss the techniques currently used to image the heart in patients with PH. Imaging modalities discussed include echocardiography, radionuclide ventriculography, cardiac computed tomography and cardiac magnetic resonance (CMR) imaging focusing on the rapidly evolving technique of CMR imaging.

Right Ventricular Tissue Doppler and Strain Imaging: Ready for Clinical Use?

Although tissue Doppler (TD) imaging of the left ventricle is now commonly used in clinical settings, TD imaging of the right ventricle (RV) is not routinely practiced. Yet, there are significant data on clinical uses of RV TD imaging, including established normal values using both color and spectral TD. In acute left ventricular (LV) inferior wall myocardial infarction, depressed RV TD velocities have been shown to correlate with the presence of RV impairment, and with patient outcome. In patients with LV heart failure, TD imaging has been correlated to RV ejection fraction by radionuclide angiography, and is an independent predictor of outcome. In patients with congenital heart disease, RV TD has been especially valuable for assessing RV function, and has been correlated to invasive hemodynamic indices, and RV ejection fraction by magnetic resonance imaging. The RV performance (Tei) index has been calculated and validated using TD-derived, rather than conventional pulsed Doppler time intervals. RV TD indices have been shown to be useful in the detection of subclinical and clinical disease in morbid obesity, chronic pulmonary, and systemic disease. TD-derived RV strain imaging can detect segmental myocardial dysfunction, overcoming limitations to conventional TD imaging resulting from tethering. For both TD velocity and strain imaging, however, appreciation of the limitations of these techniques is necessary for their appropriate use. Given its rapid acquisition times, reproducibility, and ease of addition to standard transthoracic echocardiographic protocols, RV TD and strain imaging are important additional modalities in the comprehensive echo-Doppler assessment of RV function.

Pulmonary Hypertension and Left Heart Function: Insights from Tissue Doppler Imaging and Myocardial Performance Index

BACKGROUND

As a consequence of a leftward shift of the interventricular septum and of pericardial restraint, related to the degree RV dilatation, left heart function would be influenced after pulmonary hypertension and right heart failure.

METHODS AND RESULTS

We enrolled 70 patients with pulmonary artery systolic pressure (PASP) more than 30 mmHg: 40 patients with PASP between 30 and 60 mmHg (Group 2), 30 patients with PASP more than 60 mmHg (Group 3). Another 70 patients with normal heart performance and PASP less than 30 mmHg served as the control group (Group 1). Myocardial performance index (MPI), isovolumic contraction time (IVCT), and isovolumic relaxation time (IVRT) were obtained by tissue Doppler imaging (TDI). PASP correlated negatively to peak systolic velocity of lateral tricuspid annulus (RV-Sm) and RVEF. The MPI of RV and LV in patients with severe pulmonary hypertension (Group 3) became higher as the result of the prolongation of IVRT. The higher E/Em (peak early-diastolic mitral-inflow velocity divided by early-diastolic velocity of mitral annulus) in pulmonary hypertension indicated diastolic dysfunction of LV. The decline of left ventricular ejection fraction, and also right ventricular ejection fraction, suggested LV systolic dysfunction after pulmonary hypertension. The LV-MPI truly reflected LV systolic and diastolic dysfunction in patients with pulmonary hypertension. In multiple linear regression analysis, LV-MPI was independently associated only with RV-MPI (Beta 0.47, P < 0.0001).

CONCLUSION

The result infers that the systolic and diastolic function of LV declined, following pulmonary hypertension.

Left and right ventricular diastolic dysfunction as predictors of difficult separation from cardiopulmonary bypass

PURPOSE

As the evaluation of diastolic function can be complex in the setting of a busy cardiac operating room, its assessment may benefit from an algorithmic approach using transesophageal echocardiography. We developed a diagnostic algorithm which was then applied in a series of cardiac surgery patients to determine whether moderate to severe left ventricular diastolic dysfunction (LVDD) and right ventricular diastolic dysfunction (RVDD) can predict difficult separation from cardiopulmonary bypass (DSB).

METHODS

An algorithm using pulsed-wave Doppler interrogation of the mitral and tricuspid valve, the pulmonary and hepatic venous flow, and tissue Doppler interrogation of the mitral and tricuspid annulus was developed. The study was divided in two phases involving two groups of patients undergoing cardiac surgery. In phase I, echocardiographic evaluations of patients (n = 74) were used to test the reproducibility of the algorithm and to evaluate inter-observer variability using Cohen's kappa values which were calculated in three specific periods. In phase II, the algorithm was applied to a second group of patients (validation group, n = 179) to explore its prognostic significance. The primary end-point in phase II was DSB.

RESULTS

In phase I, the kappa coefficients for LVDD and RVDD algorithms were 0.77 and 0.82, respectively. In phase II, moderate or severe degrees of LVDD were observed in 29 patients (16%) and moderate to severe RVDD was observed in 18 patients (10%) before cardiac surgery. Both moderate and severe LVDD (P = 0.017) and RVDD (P = 0.049) before surgery were observed more frequently in patients with DSB.

CONCLUSION

Moderate and severe LVDD and RVDD can be identified with very good reproducibility, and both degrees of diastolic dysfunction are associated with DSB.

Tricuspid Annular Systolic Velocity: A Useful Measurement in Determining Right Ventricular Systolic Function Regardless of Pulmonary Artery Pressures

Assessment of right ventricular (RV) systolic function can be somewhat difficult, particularly in pulmonary hypertension (PH). RV fractional area change (FAC) and tricuspid valve annular motion (TAPSE) although useful in the assessment of RV performance, their use can be sometimes limited and tedious. Thus, a quicker but yet reliable alternative is needed. Accordingly, we compared peak tricuspid annulus systolic (TA Sa) velocities derived from Doppler tissue imaging (DTI) with both RVFAC and TAPSE to estimate RV function in 52 patients (53 +/- 16 years) with varying degrees of PH. In this group, mean was RVFAC 49 +/- 20, TAPSE was 2.3 +/- 0.7 cm, peak TA Sa velocity by DTI was 10.4 +/- 3.8 cm/s, left ventricular systolic function was 57 +/- 18%, and pulmonary artery systolic pressure was 47 +/- 28 mmHg. An excellent correlation was noted between TAPSE and RVFAC (r = 0.91, P < 0.001). Similar correlations were noted between peak TA Sa velocity and RVFAC (r = 0.84, P < 0.001) and between peak TA Sa velocity and TAPSE (r = 0.90, P < 0.001). A TA Sa >10.5 cm/s identified individuals with both a normal RV function and without significant PH. Therefore, we conclude that TA Sa velocity, an easily obtainable DTI measure, that has an excellent correlation with more time-consuming methods to assess RV systolic function regardless of the degree of PH should be routinely assessed during the initial evaluation and eventual follow-up of patients either at risk or with documented PH.

Use of noninvasive tools in primary pulmonary hypertension to assess the correlation of right ventricular function with functional capacity and to predict outcome

Most patients with Primary Pulmonary Hypertension (PPH) have severe exertional limitation which ultimately leads to right heart failure and death. The purpose of the study was to assess the correlation between right ventricular (RV) systolic and diastolic noninvasive variables and exercise tolerance, as well as the predictors of adverse outcome in treated patients.

METHODS

We prospectively studied 29 patients, 17 with PPH and 12 with PPH due to collagen disease. RV parameters were assessed by echocardiography and Radionuclide ventriculography. Pulmonary function and clinical profile were assessed by 6 min walk test and NYHA class. The patients were followed-up during 2 years for cardiac death and cardiac deterioration.

RESULTS

Mean age was 51 +/- 15 years, 22 (78%) women. NYHA class1 in 2 pts, class 2 in 17, class 3 in 8 and class 4 in 2 pts. Pulmonary function (DLCO) was low in 25 (86%) pts, mean 22 +/- 48%. Six minutes walk distance was 358 +/- 132 m, RVEF was 34 +/- 11% (range 16-51%). Among RV variables, RVEF, RA area and TR were independently correlated to 6 min walk. Within follow up of 2 years, there were 10 patients with adverse outcome (4 deaths and 6 deteriorated to NYHA class 3 and 4). Among all clinical and noninvasive variables, RVEF only was correlated to adverse outcome.

CONCLUSION

The noninvasive tests of RVEF, RA size and TR were closely correlated to exercise tolerance. However, among the various clinical, functional and RV variables, RVEF was the only variable correlated with adverse outcome in pts with PPH.

Severe tricuspid regurgitation shows significant impact in the relationship among peak systolic tricuspid annular velocity, tricuspid annular plane systolic excursion, and right ventricular ejection fraction

OBJECTIVES

Peak systolic mitral annular velocities correlate with left ventricular ejection fraction (EF) regardless of mitral regurgitation severity. Peak systolic tricuspid annular velocity (RV-Sm) and tricuspid annular plane systolic excursion (TAPSE) are used to assess right ventricular (RV) EF (RVEF). We investigated whether tricuspid regurgitation (TR) affects the relationship among RV-Sm, TAPSE, and RVEF.

METHODS

Patients (n = 625) underwent echocardiography and Doppler tissue studies. Left ventricular EF and RVEF were estimated by Simpson's rule. Because of confounding, we excluded patients with diseases that influence mitral annular motion or left ventricular function. We finally enrolled 225 patients: 125 with mild TR, 50 with moderate TR, and 50 with severe TR. Forty study patients (20 with mild TR, 10 with moderate TR, and 10 with severe TR) received radionuclide ventriculography.

RESULTS

The RVEF estimated by Simpson's method correlated strongly to that estimated by the radionuclide method (r = 0.793, r2 = 0.629, P < .0001). With mild or moderate TR, RV-Sm correlated well to RVEF (mild TR group: r = 0.765, r2 = 0.59, P < .0001; moderate TR group: r = 0.756, r2 = 0.57, P < .0001). RV-Sm had no significant correlation to RVEF in patients with severe TR (r = 0.212, r2 = 0.05, P = .167). Over a range of TR severities, the relationship between TAPSE and RVEF showed a similar trend to that between RV-Sm and RVEF.

CONCLUSION

Severe TR has a significant impact on the relationship between RV-Sm and RVEF and between TAPSE and RVEF. TAPSE and RV-Sm in patients with severe TR show poor correlation to RVEF. When applying Doppler tissue method or TAPSE to assess RV function, severe TR is a significantly confounding factor.

The determinants of right ventricular function in patients with atrial septal defect

OBJECTIVE

The purpose of this study was to ascertain the determinants of right ventricular (RV) systolic and diastolic functions in patients with atrial septal defect.

METHODS

Thirty-three patients with atrial septal defect having left to right shunt were enrolled in this study. RV function parameters were assessed echocardiographically. RV systolic function was assessed using tricuspid tissue Doppler S velocity (St). With regard to RV diastolic function parameters, E/A ratio, deceleration time (DT), E/Et ratio (Et = tissue Doppler E velocity), RV isovolumetric relaxation time (RVIVRT) were assessed. RV myocardial performance index (MPI) was calculated as an index of both systolic and diastolic function. Pulmonary artery stiffness (PAS) was also calculated. After echocardiography, right and left heart catheterization was performed. Mean pulmonary artery pressure (MPAP), mean right atrial pressure (MRAP), systemic flow (Qs), pulmonary flow (Qp), systemic vascular resistance (SVR), and pulmonary vascular resistance (PVR) were obtained using the data of invasive measurements.

RESULTS

In multivariate analysis, MPAP was found to be the parameter closest related to RVIVRT (r = 0.73, p < 0.001) and E/Et (r = 0.66, p < 0.001), while PAS was found to be the parameter closest related to MPI (r = 0.53, p = 0.002). In addition, St velocity was found the only parameter related to PVR (r = -0.39) in univariate analysis. There was no relationship between QP/QS and any of the RV function parameters.

CONCLUSION

The pulmonary vascular bed appears to be the predictor of the RV functions in patients with atrial left to right shunts, and the amount of the shunt seems to have no direct adverse influence on the RV functions.

Pulmonary Embolism and Right Heart Function: Insights from Myocardial Doppler Tissue Imaging

BACKGROUND

Acute pulmonary embolism (PE) has significant impact in right heart function. We assess the difference of Doppler tissue parameters among control subjects, patients with pulmonary hypertension, and patients with acute PE. After optimal treatment, the changes of Doppler tissue parameters in patients with PE were assessed.

METHODS

A total of 50 patients with acute PE, confirmed by multidetector-row chest computed tomography, were enrolled. Another 70 patients with pulmonary hypertension, but no evidence of PE found by computed tomography, were also enrolled. A total of 100 healthy people without signs of cardiopulmonary dysfunction served as a control group. We assessed left and right ventricular (RV) ejection fraction by Simpson's rule. Doppler tissue parameters were obtained from lateral sides of tricuspid and mitral annulus, and interventricular septum. Myocardial performance index (MPI) of RV was estimated from lateral tricuspid annulus by Doppler tissue imaging, MPI of left ventricle from lateral mitral annulus.

RESULTS

The left ventricular and RV ejection fractions in patients with pulmonary hypertension were lower than for the control group and patients with PE. But the RV-MPI in patients with PE was the lowest as a result of significant prolongation of isovolumic relaxation time (IVRT). One month after anticoagulant treatment, the IVRT and RV-MPI recovered in patients with PE. There was no significant correlation between IVRT and pulmonary artery systolic pressure. By bivariate correlation analysis, the most significant factor correlated to pulmonary artery systolic pressure was peak late diastolic velocity of tricuspid annulus with r 0.67, r(2) 0.45, and P less than .0001.

CONCLUSIONS

Acute PE has significant impact in systolic and diastolic function of RV. The higher RV-MPI implies that condition. However, optimal anticoagulant treatment corrects RV dysfunction in patients with PE. After a 1-month course of anticoagulant treatment, RV-MPI diminishes as the result of RV-IVRT reduction.

Tissue Doppler Evaluation of Tricuspid Annulus for Estimation of Pulmonary Artery Pressure in Patients with COPD

Because transthoracic echocardiography is an inexpensive, easy, and reproducible method, it is the most commonly used noninvasive diagnostic tool to determine pulmonary artery pressure (PAP). Tissue Doppler imaging (TDI) emerged as a new echocardiographic method that can be applied in various clinical conditions. In our study we aimed to evaluate the relationship between tricuspid lateral annulus TDI parameters and pulmonary artery systolic pressure (PASP) as estimated by continuous wave Doppler in patients with chronic obstructive pulmonary disease (COPD). A total of 51 (42 men, mean age: 62.3 +/- 8.2 years) patients with clinically stable COPD were included in the study. The tricuspid annular systolic myocardial velocity (Sm), velocity time integral of Sm (SmVTI), early (Em) and late (Am) peak diastolic myocardial velocities, and myocardial isovolumic relaxation time (IVRTm) were acquired as well as two-dimensional (2-D) and conventional Doppler data. When compared with values of patients without pulmonary hypertension (PHT), Sm, SmVTI, Em, and Em/Am values were found to be lower and IVRTm values higher in patients with PHT. When all the patients were analyzed, there was a significant negative correlation between PASP and Sm and SmVTI (r = -0.82, p < 0.001 and r = -0.84, p < 0.001, respectively). Sm velocity < or = 12 cm/s had a sensitivity of 85% and a specificity of 93.3% for predicting PASP > 40 mmHg. SmVTI < or = 2.5 cm had a sensitivity of 85.7% and a specificity of 90% for detecting PHT. In our study, there was significant negative correlation between tricuspid lateral annular Sm and SmVTI values and PASP in patients with stable COPD irrespective of the presence of PHT. Tricuspid annular Sm and SmVTI had very good level sensitivity and specificity for predicting PHT. In conclusion, it might be suggested that in cases where noninvasive PASP measurement is not possible, TDI can be used as an alternative and reliable method to assess PAP.

Prognostic value of intra-left ventricular electromechanical asynchrony in patients with mild hypertrophic cardiomyopathy compared with power athletes

OBJECTIVES

We sought to assess the indexes of myocardial activation delay, using Doppler myocardial imaging (DMI), as potential diagnostic tools and predictors of cardiac events in patients with hypertrophic cardiomyopathy (HCM) compared with power athletes.

BACKGROUND

the distribution and magnitude of left ventricular (LV) hypertrophy are not uniform in patients with HCM, which results in heterogeneity of regional LV systolic function.

METHODS

The study population comprised 70 young patients with HCM (mean (SD) age 29.4 (5.9) years) with mild septal hypertrophy (15-19 mm) and 85 age and sex matched athletes with septal thickness >12 mm, followed up for 44.4 (10.8) months. Using pulsed DMI, myocardial peak velocities, systolic time intervals, and myocardial intraventricular and interventricular systolic delays were measured in six different basal myocardial segments.

RESULTS

DMI analysis showed in HCM lower myocardial both systolic and early diastolic peak velocities of all the segments. Patients with HCM also showed significant interventricular and intraventricular delay (p<0.0001), whereas athletes showed homogeneous systolic activation of the ventricular walls. During the follow up, seven sudden deaths occurred in the HCM group, while no cardiovascular event was observed in the group of athletes. In patients with HCM, intraventricular delay on DMI was the most powerful independent predictor of sudden cardiac death (p<0.0001). An intraventricular delay >45 ms identified with high sensitivity and specificity patients with HCM at higher risk of ventricular tachycardia and cardiac events (test accuracy 90.6%).

CONCLUSIONS

DMI may be a valid supporting tool for the differential diagnosis between HCM and "athlete's heart". In patients with HCM, DMI indexes of intraventricular delay may provide additional information for selecting subgroups of patients with HCM at increased risk of ventricular arrhythmias and sudden cardiac death at follow up. Accordingly, such patients may benefit from early intensive treatment and survey. MINIABSTRACT: Doppler myocardial imaging may represent a valid supporting tool for the differential diagnosis between mild hypertrophic cardiomyopathy (HCM) and "athlete's heart". In patients with HCM, DMI indexes of intraventricular delay may provide additional information for selecting subgroups of patients with HCM at increased risk of ventricular arrhythmias and sudden cardiac death at follow up.

Right ventricular diastolic abnormalities in rheumatoid arthritis and its relationship with left ventricular and pulmonary involvement. A tissue Doppler echocardiographic study

OBJECTIVES

To investigate right ventricular diastolic function in rheumatoid arthritis (RA) and its relationship with left ventricular and pulmonary involvement.

METHODS

Thirty-five RA patients and 30 healthy subjects were submitted to conventional Doppler (CE) and tissue Doppler echocardiography (TDE) to assess left and right systolic and diastolic function and to estimate maximal arterial systolic pulmonary pressure (PAP). To detect pulmonary involvement, pulmonary function tests and high-resolution computed tomography (HRCT) scans were performed in all RA patients.

RESULTS

An abnormal RV filling, as expressed byan inverted tricuspid (Tr.) E/A ratio, was detected in 12 (34%) of the 35 RA patients and in 2 (7%) of the 30 controls (P<0.004). If compared to CE findings, prevalence of RV diastolic abnormalities were found higher in patients with RA by TDE (RV annulus Em/Am ratio <1 (in 31 (89%) of 35 patients) (P = 0.002). Twenty-two (63%) of 35 patients had abnormal HRCT findings. Pulmonary involvement with pulmonary hypertension (PHT) (36+/-5 mmHg) was detected in 10 (29%) of 35 RA. In this group, increase of RV annulus and basal Am wave, decrease of Tr. E/A ratio and RV annulus Em/Am ratio were statistically significant compared to RA (12 (34%) of 35) patients with pulmonary involvement who had normal PAP (19+/-5 mmHg), (P = 0.014, P = 0.006, P = 0.015, P = 0.049, respectively).

CONCLUSIONS

This study points out an impaired RV filling in a significant part of RA patients without overt heart failure. Impairment of RV diastolic function may be a predictor of subclinic myocardial and pulmonary involvement in patients with RA.

Right Heart Function in Systemic Lupus Erythematosus: Insights from Myocardial Doppler Tissue Imaging

The purpose of this study was to use Doppler tissue imaging to evaluate heart function and to investigate the correlation between Doppler imaging and pulmonary artery systolic pressure (PASP) and right ventricular (RV) ejection fraction (EF) in patients with systemic lupus erythematosus (SLE). Standard echocardiography and 2-dimensional and color Doppler imaging were used to assess cardiac function in patients given the diagnosis of SLE (n = 40) and healthy control subjects (n = 45). Half of the patients with SLE also presented with pulmonary hypertension (PH). Significant differences in PASP and RV EF (RVEF) were found between the control and SLE groups. The peak systolic velocity of tricuspid annulus was significantly lower in patients with SLE than in the control group. The calculated myocardial performance index of the RV, septum, and left ventricular lateral wall were significantly higher in patients with SLE than in the control group. Bivariate correlation analysis revealed a significant correlation among PASP, RVEF, and systolic tricuspid annular velocity. There was a significant correlation between each of these 3 parameters and the 6-minute walk distance in patients with SLE. Patients with SLE and PH had a significantly shorter 6-minute walk distance than patients with SLE without PH. Furthermore, in patients with SLE and PH, RVEF and systolic tricuspid annular velocity were lower than in the control subjects and patients with SLE without PH. Patients with SLE and PH had a longer isovolumic relaxation time and a higher myocardial performance index of RV than those without PH. Finally, by simple linear regression analysis, we found a significant positive relation between RVEF and systolic tricuspid annular velocity, but a negative relationship between PASP and systolic tricuspid annular velocity. These findings demonstrate that in patients with SLE, systolic tricuspid annular velocity determined by echocardiography and Doppler imaging can be used to assess RV function and PASP. Furthermore, systolic tricuspid annular velocity reflects exercise tolerance in patients with SLE and the length of the isovolumic relaxation time represents the progression of PH.

Myocardial Systolic Activation Delay in Patients with Left Bundle Branch Block and Either Normal or Impaired Left Ventricular Function

AIM OF THE STUDY

to evaluate determinants of myocardial activation delay of both left (LV) and right (RV) ventricle in patients with left bundle branch block (LBBB) and either normal or impaired LV ejection fraction (EF).

METHODS

From an initial cohort of patients with LBBB, 42 patients with dilated cardiomyopathy (group A) and 33 with normal global LV systolic function (group B), all comparable in age and sex, underwent standard Doppler echo, pulsed Doppler myocardial imaging (DMI), and coronary angiography. Using DMI, the following regional parameters were evaluated in five different basal myocardial segments (LV anterior, inferior, septal, lateral walls-RV lateral wall): systolic (Sm), early- and late-diastolic (Em and Am) peak velocities. As index of myocardial systolic activation was calculated: precontraction time (PCTm) (from the beginning of Q-wave of ECG to the onset of Sm). Intraventricular systolic dyssynchrony was analyzed by difference of PCTm in different LV myocardial segments. Interventricular activation delay was calculated by the difference of PCTm between the most delayed LV segment and RV lateral wall.

RESULTS

Patients of group A showed increased heart rate (HR), QRS duration and LV end-diastolic diameter, and reduced LV EF. By DMI, patients of group A showed reduced myocardial peak velocities and a significant intraventricular delay in activation of LV lateral wall, with increased regional PCTm (P < 0.001). In addition, patients with dilated cardiomyopathy showed a more pronounced interventricular dyssynchrony, even after adjustment for HR and QRS duration. By receiver operating characteristic (ROC) curve analysis, a cut-off value of 55 msec of interventricular delay showed 86% sensitivity and 92% specificity in identifying patients with impaired EF. In the overall population, by use of stepwise forward multivariate linear regression analyses, LV end-diastolic diameter (beta coefficient = 0.52; P < 0.001) and LV EF (beta coefficient =-0.58; P < 0.0001) were the only independent determinants of interventricular activation delay.

CONCLUSIONS

Pulsed DMI is an effective noninvasive technique for assessing the severity of regional delay in activation of LV walls in patients with LBBB. The impairment of interventricular systolic sychronicity is strongly related to LV dilatation and to the degree of global systolic dysfunction. Therefore, patients with dilated cardiomyopathy suitable for cardiac resynchronization therapy may be better selected.

Right ventricular myocardial isovolumic relaxation time and pulmonary pressure. Pulsed Doppler tissue imaging in resurrection of Burstin's nomogram

AIMS

Non-invasive assessment of pulmonary artery systolic pressure (PASP) has several limitations. As previously described by Burstin, the right ventricular (RV) isovolumic relaxation time (IVRt) is sensitive to changes in PASP. We therefore compared RV myocardial IVRt, derived by Doppler tissue imaging (DTI), with simultaneously measured invasive PASP.

METHODS AND RESULTS

Twenty-six consecutive patients (18 males, mean age 52 +/- 12 years, range 23-75) underwent a simultaneous Doppler echocardiography, including DTI, and cardiac catheterization examination for measurement of PASP and right atrial mean pressures. IVRt was measured using the myocardial velocities by pulsed DTI at both basal and mid cavity segments of the RV free wall. As diastolic time intervals are influenced by heart rate IVRt was corrected for heart rate (IVRt/RR%). A significant correlation was found between PASP and regional IVRt/RR% at both the basal (r = 0.42, P<0.05) and mid cavity segment (r = 0.71, P<0.001). Furthermore, when only patients with normal right atrial pressures (<7 mmHg) were taken into account, the correlation coefficient improved at both basal and mid cavity segments (r = 0.74, P<0.05 and r = 0.83, P<0.01).

CONCLUSION

Pulsed Doppler-derived IVRt correlates well with PASP. The use of pulsed DTI for measurement of IVRt is simple, reproducible and easy to obtain. We propose this method as an additional non-invasive tool in the assessment of PASP.