Utility of Right Ventricular Strain Imaging in Predicting Pulmonary Vascular Resistance in Patients With Pulmonary Hypertension

Two-dimensional speckle tracking echocardiography assessed right ventricular function and exercise capacity in pre-capillary pulmonary hypertension

Resting two-dimensional speckle tracking echocardiography (2D-STE) identified right ventricular (RV) systolic function were reported to predict exercise capacity in pulmonary hypertension (PH) patients, but little attention had been payed to 2D-STE detected RV diastolic function. Therefore, we aim to elucidate and compare the relations between 2D-STE identified RV diastolic/systolic functions and peak oxygen consumption (PVO₂) determined by cardiopulmonary exercise testing (CPET) in pre-capillary PH. 2D-STE was performed in 66 pre-capillary PH patients and 28 healthy controls. Linear correlation and multivariate regression analyses were performed to evaluate and compare the relations between RV 2D-STE parameters and PVO₂. Receiver operating characteristic curves were used to compare the predictive value of 2D-STE parameters in predicting the cut-off-PVO₂ < 11 ml/min/kg. There were significant differences of all the 2D-STE parameters between PH patients and healthy controls. In patients, RV-peak global longitudinal strain (GLS, r_s = - 0.498, P < 0.001), RV- peak systolic strain rate (GSRs, r_s = - 0.537, P < 0.001) and RV- peak early diastolic strain rate (GSRe, r_s = 0.527, P < 0.001) significantly correlated with PVO₂, but no significant correlation was observed between RV- peak late diastolic strain rate (GSRa, r_s = 0.208, P = 0.093) and PVO₂. The first multivariate regression analysis of clinical data without echocardiographic parameters identified WHO functional class, NT-proBNP and BMI as independent predictors of PVO₂ (Model-1, adjusted r² = 0.421, P < 0.001); Then we added conventional echocardiographic parameters and 2D-STE parameters to the clinical data, identified S,(Model-2,adjusted r² = 0.502, P < 0.001), RV-GLS (Model-3, adjusted r² = 0.491, P < 0.001), RV-GSRe (Model-4, adjusted r² = 0.500, P < 0.001) and RV-GSRs (Model-5, adjusted r² = 0.519, P < 0.001) as independent predictors of PVO₂, respectively. The predictive power was increased, and Model-5 including RV-GSRs showed the highest predictive capability. ROC curves found RV-GSRs expressed the strongest predictive value (AUC = 0.88, P < 0.001), and RV-GSRs > - 0.65/s had a 88.2% sensibility and 82.2% specificity to predict PVO₂ < 11 ml/min/kg. 2D-STE assessed RV function improves the prediction of exercise capacity represented by PVO₂ in pre-capillary PH.

Right ventricular function mirrors clinical improvement with use of prostacyclin analogues in pediatric pulmonary hypertension

Pulmonary hypertension (PH) causes significant morbidity and mortality in children due to right ventricular (RV) failure. We sought to determine the effect of prostacyclin analogues on RV function assessed by echocardiography in children with PH. We conducted a retrospective cohort study of children with PH treated with a prostacyclin analogue (epoprostenol or treprostinil) between January 2001 and August 2015 at our center. Data were collected before initiation of treatment (baseline) and at 1–3 and 6–12 months after. Protocolized echocardiogram measurements including tricuspid annular plane systolic excursion (TAPSE) and RV global longitudinal strain were made with blinding to clinical information. Forty-nine individuals (65% female), aged 0–29 years at the time of prostacyclin initiation were included. Disease types included pulmonary arterial hypertension (idiopathic [35%], heritable [2%], and congenital heart disease-associated [18%]), developmental lung disease (43%), and chronic thromboembolic PH (2%). Participants received intravenous (IV) epoprostenol (14%) and IV/subcutaneous (SQ) (67%) or inhaled (18%) treprostinil. Over the study period, prostacyclin analogues were associated with improvement in TAPSE (P = 0.007), RV strain (P < 0.001), and qualitative RV function (P = 0.037) by echocardiogram, and BNP (P < 0.001), functional class (P = 0.047) and 6-min walk distance (P = 0.001). TAPSE and strain improved at early follow up (P = 0.05 and P = 0.002, respectively) despite minimal RV pressure change. In children with PH, prostacyclin analogues are associated with an early and sustained improvement in RV function measured as TAPSE and strain as well as clinical markers of PH severity. RV strain may be a sensitive marker of RV function in this population.

Echocardiographic right ventricular function correlations with cardiac catheterisation data in biventricular congenital heart patients

BACKGROUND

Newer echocardiographic techniques may allow for more accurate assessment of right ventricular function. Adult studies have correlated these echocardiographic measurements with invasive data, but minimal data exist in the paediatric congenital heart population. The purpose of this study was to evaluate echocardiographic measurements that correlate best with right ventricular systolic and diastolic catheterisation parameters.

METHODS

Patients with two-ventricle physiology who underwent simultaneous echocardiogram and cardiac catheterisation were included in this study. Right ventricular systolic echocardiographic data included fractional area change, displacement, tissue Doppler imaging s' wave, global longitudinal strain, and strain rate s' wave. Diastolic echocardiographic data included tricuspid E and A waves, tissue Doppler imaging e' and a' waves, and strain rate e' and a' waves. E/tissue Doppler imaging e', tissue Doppler imaging e'/tissue Doppler imaging a', E/strain rate e', and strain rate e'/strain rate a' ratios were also calculated. Catheterisation dP/dt was used as a marker for systolic function and right ventricular end-diastolic pressure for diastolic function.

RESULTS

A total of 32 patients were included in this study. The median age at catheterisation was 3.1 years (0.3-17.6 years). The DP/dt was 493±327 mmHg/second, and the right ventricular end-diastolic pressure was 7.7±2.4 mmHg. There were no significant correlations between catheterisation dP/dt and systolic echocardiographic parameters. Right ventricular end-diastolic pressure correlated significantly with strain rate e' (r=-0.4, p=0.02), strain rate a' (r=-0.5, p=0.03), and E/tissue Doppler imaging e' (r=0.4, p=0.04).

CONCLUSION

Catheterisation dP/dt did not correlate with echocardiographic measurements of right ventricular systolic function. Strain rate and tissue Doppler imaging analysis significantly correlated with right ventricular end-diastolic pressure. These values should be further studied to determine whether they may be used as an alternative method to estimate right ventricular end-diastolic pressure in this patient population.

Right ventricular strain as predictor of pulmonary complications in patients with femur fracture

Background:

Following femur fracture, medullary fat enters the systemic circulation and altered pulmonary haemodynamics may contribute to pulmonary complications. This study evaluated the association between right ventricular (RV) function and pulmonary complications in patients with femur fracture.

Methods:

Patients with a femur fracture who had undergone pre-operative echocardiography that included RV peak global longitudinal strain (RV GLS) were evaluated retrospectively between March 2015 and February 2016. Pulmonary complications were defined as the development of pneumonia or pulmonary thromboembolism during the first postoperative month.

Results:

Among 78 patients, pulmonary complications developed in eight (10.3%). The RV GLS value of all patients was lower than the normal range. In addition, the RV GLS value of patients with pulmonary complications was significantly lower than that of patients without pulmonary complications. Multivariate regression analyses found that worse RV GLS values independently predicted pulmonary complications [odds ratio (OR) 2.09, 95% confidence interval (CI) 1.047–4.151, p = 0.037]. Receiver operating characteristic curve analysis found that a RV GLS value of –14.85% was the best cut-off value to predict pulmonary complications; sensitivity: 75.0%; specificity: 62.9%. Moreover, patients with RV GLS values > –14.85% had significantly lower pulmonary complication-free survival.

Conclusions:

In patients with femur fracture, RV GLS values could help predict pulmonary complications. Therefore, patients with RV GLS values > –14.85 should be monitored closely before and after surgery for femur fracture.

Assessment of regional right ventricular systolic function in patients with obstructive sleep apnea syndrome using velocity vector imaging

Obstructive sleep apnea syndrome (OSAS) is the most common type of sleep disorder which is associated with a series of cardiovascular disorders, including right ventricular (RV) dysfunction. However, it is difficult to assess the RV function systematically using a conventional echocardiography because RV has a complex geometrical shape. A case-control study was performed to assess the regional right ventricular potential dysfunction in patients with OSAS using velocity vector imaging (VVI) from March 2014 to October 2015.Sixty-nine patients with OSAS were divided into 3 groups: mild, moderate, and severe according to the apnea-hypopnea index (AHI). A total of 31 cases of healthy subjects were enrolled as the control group. Digital images of apex 4-chamber views were acquired to measure the peak systolic velocity (V), strain (ST), and strain rate (STR) of right ventricular free wall (RVFW) basal, middle, and apical segments using VVI.The peak systolic velocity of RVFW basal segments in the mild OSAS group increased (t = 2.22, P = 0.049) and gradually reduced in the moderate and severe groups compared with the controls. The values of systolic ST and STR of apical segments decreased in the mild OSAS group compared with the normal control group (t = 3.30, P = 0.02; t = 3.75, P = 0.01, respectively), and decreased furthermore in the moderate and severe OSAS groups.The change in the right ventricular regional systolic function starts before the development of heart dysfunction and pulmonary hypertension. At the early stage of OSAS, the deformation decreases in the RVFW apical segment, and the peak systolic velocities increase in the RVFW basal segment. The VVI is a sensitive method which is expected to be a worthy technique for early clinical therapy in patients with OSAS.

Transthoracic echocardiography for the evaluation of children and adolescents with suspected or confirmed pulmonary hypertension. Expert consensus statement on the diagnosis and treatment of paediatric pulmonary hypertension. The European Paediatric Pulmonary Vascular Disease Network, endorsed by ISHLT and D6PK

Transthoracic echocardiography (TTE) is a useful method for non-invasive screening of patients at risk of pulmonary hypertension (PH). Since TTE often serves as the initial study before invasive cardiac catheterisation, misinterpretation of TTE variables may lead to missed or delayed diagnosis with devastating consequences for the patients, or unnecessary invasive diagnostics that have inheriting risks. Due to the heterogeneous anatomy in congenital heart disease, particularly the assessment of myocardial function in children with PH is challenging. Here, we present recommendations on the use of TTE in the screening, diagnosis and follow-up of patients with PH, and discuss the limitations of this non-invasive imaging technique. This expert consensus statement focuses on key TTE variables used to determine the pressure in the pulmonary artery, myocardial contractility and systolic and diastolic function of the RV and LV. A particular focus is on the TTE assessment of RV function and geometry. According to the published data on the application of TTE in PH in childhood, we suggest a structured approach for non-invasive assessment of pulmonary artery pressure and myocardial function that may help to identify patients with early ventricular deterioration and their response to advanced pharmacotherapy. In addition to clinical and biochemical markers, serial examination of patients with PH using a standardised TTE approach, determining conventional and several more novel echocardiographic variables may allow early diagnosis and treatment, better recognition of disease progression and guide tailored therapy.

Transthoracic echocardiography in the evaluation of pediatric pulmonary hypertension and ventricular dysfunction

Transthoracic echocardiography (TTE) is the most accessible noninvasive diagnostic procedure for the initial assessment of pediatric pulmonary hypertension (PH). This review focuses on principles and use of TTE to determine morphologic and functional parameters that are also useful for follow-up investigations in pediatric PH patients. A basic echocardiographic study of a patient with PH commonly includes the hemodynamic calculation of the systolic pulmonary artery pressure (PAP), the mean and diastolic PAP, the pulmonary artery acceleration time, and the presence of a pericardial effusion. A more detailed TTE investigation of the right ventricle (RV) includes assessment of its size and function. RV function can be evaluated by RV longitudinal systolic performance (e.g., tricuspid annular plane systolic excursion), the tricuspid regurgitation velocity/right ventricular outflow tract velocity time integral ratio, the fractional area change, tissue Doppler imaging-derived parameters, strain measurements, the systolic-to-diastolic duration ratio, the myocardial performance (Tei) index, the RV/left ventricle (LV) diameter ratio, the LV eccentricity index, determination of an enlarged right atrium and RV size, and RV volume determination by 3-dimensional echocardiography. Here, we discuss the potential use and limitations of TTE techniques in children with PH and/or ventricular dysfunction. We suggest a protocol for TTE assessment of PH and myocardial function that helps to identify PH patients and their response to pharmacotherapy. The outlined protocol focuses on the detailed assessment of the hypertensive RV; RV-LV crosstalk must be analyzed separately in the evaluation of different pathologies that account for pediatric PH.

Left Atrial Intrinsic Strain Rate Correcting for Pulmonary Wedge Pressure Is Accurate in Estimating Pulmonary Vascular Resistance in Breathless Patients

OBJECTIVES

We hypothesized that left atrial deformation during atrial systole (LASRa) correlates with pulmonary capillary wedge pressure (PCWP), thus enabling echo-derived pulmonary vascular resistance (PVR) estimation in a wide range of different subsets of patients.

BACKGROUND

Various etiologies of pulmonary hypertension (PH) have different mechanisms and treatments for breathlessness. Irrespective of the location of the underlying pulmonary vascular pathology, pre- or postcapillary, the resulting PH is fairly easy to assess by Doppler echocardiography, but PVR remains a challenge.

METHODS

We prospectively included 46 patients (mean age 61 ± 13 years) in sinus rhythm, who underwent right heart catheterization because of dyspnea. According to the NICE guidelines classification, 22 belonged to group 1 pulmonary artery hypertension (PAH), 19 belonged to group 2 congestive heart failure (CHF), 1 belonged to group 4 chronic thromboembolic pulmonary hypertension (CTEPH), and 4 had normal hemodynamics. Simultaneous Doppler echocardiography using spectral, tissue Doppler, and speckle tracking echocardiography techniques for assessing LA structure and function was performed.

RESULTS

PCWPrhc correlated with LASRa (r(2) = 0.65, P < 0.001). PCWPecho was calculated using the equation (PCWPecho = 26.12 - 11.09 × LASRa), and the resulting PVR echo strongly correlated with the respective catheter-based measurements PVRrhc (r(2) = 0.69. P < 0.001) with a sensitivity of 85% and specificity of 74% identifying a PVR ≥ 3 WU.

CONCLUSIONS

Left atrial strain rate during atrial systole correlates closely with pulmonary capillary wedge pressure and consequently the calculated pulmonary vascular resistance, irrespective of the etiology of PH.

Peri-operative assessment of right heart function: role of echocardiography

The right heart contributes significantly to overall cardiac function. Right ventricular (RV) haemodynamics and function have been defined to be physiologically different from the left ventricle, and yet independently associated with outcomes in a spectrum of conditions. In particular, RV function has been shown to influence prognosis of patients undergoing surgery. The assessment of right heart function during the intra-operative and immediate postoperative periods plays an important role in the clinical management of patients having surgery. While a number of techniques are available for the assessment of the right heart intra-operatively, echocardiography remains the prime choice being least invasive, relatively safe, readily accessible and cost-effective. Advancements in the field of echocardiographic have improved ability to assess right heart function. This review examines the role echocardiography and advances in this imaging modality in the assessment of right heart function within the peri-operative setting.

Usefulness of right ventricular basal free wall strain by two-dimensional speckle tracking echocardiography in patients with chronic thromboembolic pulmonary hypertension

Recently two-dimensional (2D) speckle tracking echocardiography (STE) derived from right ventricular (RV) free wall has been shown to be a very useful tool for the estimation of RV performance. The purpose of this study was to examine whether RV basal free wall strain can detect increased mean pulmonary arterial pressure (mPAP) in patients with chronic thromboembolic pulmonary hypertension (CTEPH). We investigated a total of 126 patients with CTEPH (mean age, 56 ± 12 years). They underwent echocardiography and right heart catheter examination. 2D STE-derived longitudinal strain was measured by placing 2 regions of interests (ROIs) on the RV basal free wall in RV-focused apical 4-chamber view. Peak strain (RV-PS) was acquired between the 2 ROIs. Conventional echocardiographic RV parameters (RV fractional area change, RV myocardial performance index, tricuspid annular plane systolic excursion, tricuspid annular peak systolic velocity, and tricuspid regurgitant pressure gradient) were evaluated as well. Right heart catheterization was performed on the day following of echocardiographic evaluation. Among RV echo parameters, RV-PS showed the best correlation with mPAP (r = 0.75, P < 0.0001). Receiver operating characteristic analysis revealed that a cut-off value of RV-PS -20.8% could detect mPAP ≧ 25 mmHg (sensitivity 78%, specificity 93%, area under the curve 0.90, P < 0.001). RV basal free wall strain was a useful tool for the non-invasive detection of increased mPAP in patients with CTEPH.