Right ventricular longitudinal deformation parameters and exercise capacity : prognosis of patients with chronic thromboembolic pulmonary hypertension

Performance-based outcome measures for assessing physical capacity in patients with pulmonary embolism: A scoping review

INTRODUCTION

Up to 50 % of patients surviving a pulmonary embolism (PE) report persisting shortness of breath, reduced physical capacity and psychological distress. As the PE population is heterogeneous compared to other cardiovascular patient groups, outcome measures for assessing physical capacity traditionally used in cardiac populations may not be reliable for the PE population as a whole. This scoping review aims to 1) map performance-based outcome measures (PBOMs) used for assessing physical capacity in PE research, and 2) to report the psychometric properties of the identified PBOMs in a PE population.

METHODS

The review was conducted according to the Joanna Briggs Institute framework for scoping reviews and reported according to the PRISMA-Extension for Scoping Reviews guideline.

RESULTS

The systematic search of five databases identified 4585 studies, of which 243 studies met the inclusion criteria. Of these, 185 studies focused on a subgroup of patients with chronic thromboembolic pulmonary hypertension. Ten different PBOMs were identified in the included studies. The 6-minute walk test (6MWT) and cardiopulmonary exercise test (CPET) were the most commonly used, followed by the (Modified) Bruce protocol and Incremental Shuttle Walk test. No studies reported psychometric properties of any of the identified PBOMs in a PE population.

CONCLUSIONS

Publication of studies measuring physical capacity within PE populations has increased significantly over the past 5-10 years. Still, not one study was identified, reporting the validity, reliability, or responsiveness for any of the identified PBOMs in a PE population. This should be a priority for future research in the field.

The Role of Strain by Cardiac Magnetic Resonance Imaging in Predicting the Prognosis of Patients with Chronic Thromboembolic Pulmonary Hypertension

Chronic thromboembolic pulmonary hypertension (CTEPH) is characterized by thrombotic obstruction of the pulmonary arteries, and right ventricular (RV) dysfunction is a major cause of death. Cardiac magnetic resonance (CMR) is the gold standard for assessing heart wall deformation; therefore, we aimed to determine the prognostic value of CMR strain in patients with CTEPH. Strain derived by CMR was measured at the time of diagnosis in 45 patients with CTEPH, and the relationship between RV strain and prognosis was determined through follow-up. The value of RV strain in the prognostic model was compared with that of pulmonary arterial hypertension (PAH) risk stratification. The RV global peak longitudinal strain (GLS) and global peak circumferential strain (GCS) in CTEPH patients were lower than the normal references of RV strain in the control group. GLS and longitudinal strain in the basal segment were independent risk factors for adverse events (P < .050). Adding CMR parameters to PAH risk stratification improved its predictive power in patients with CTEPH. GLS and GCS scores were impaired in patients with chronic RV overload. RV strain derived by CMR imaging is a promising noninvasive tool for the follow-up of patients with CTEPH.

Riociguat and the right ventricle in pulmonary arterial hypertension and chronic thromboembolic pulmonary hypertension

Pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTEPH) are progressive diseases that can lead to right heart failure and death. Right ventricular dysfunction, hypertrophy and maladaptive remodelling are consequences of increased right ventricular (RV) afterload in PAH and CTEPH and are indicative of long-term outcomes. Because RV failure is the main cause of morbidity and mortality in PAH and CTEPH, successful treatments should lead to improvements in RV parameters. Riociguat is a soluble guanylate cyclase stimulator approved for the treatment of PAH and inoperable or persistent/recurrent CTEPH after pulmonary endarterectomy. This review examines the current evidence showing the effect of riociguat on the right ventricle, with particular focus on remodelling, function and structural parameters in preclinical models and patients with PAH or CTEPH.

Noninvasive Predictors of Functional Capacity in Patients with Pulmonary Hypertension due to Congenital Heart Disease: A Pilot Echocardiography Single-Center Study

Background

Pulmonary hypertension (PH) with congenital heart disease (CHD) affects the functional capacity (FC), quality of life, and survival. However, the importance of different echocardiographic parameters and their correlation with FC is unclear.

Methods and Results

A custom-made sheet for 34 consecutive patients with PH due to CHD was made to include patient's demographic data, underlying cardiac disorder, and FC by 6-min walk test (6MWT). The patients were subdivided into Group 1 with 6MWT < 330 m and Group 2 with 6MWT > 330 m. A cutoff value of 330 m was selected because it reflected the survival and outcome of patients in many studies before. Left ventricle global radial strain, baseline saturation, and saturation after 6MWT showed a significant strong positive correlation with 6MWT (r = 0.755, 0.714, and 0.721, P = 0.001, 0.000, and 0.000, respectively). Multiple regression analysis using a multivariate model showed that the mean pulmonary artery pressure (MPAP) and baseline saturation are the most independent predictors of the FC (P = 0.028 and 0.049, respectively), with a cutoff point for MPAP > 30 mmHg (area under the curve [AUC]: 0.85) with a sensitivity and specificity of 69.23% and 95.24%, respectively, and cutoff point for saturation < 94% (AUC: 0.852) with a sensitivity and specificity of 92.31% and 76.19%, respectively.

Conclusion

The MPAP and the baseline oxygen saturation were the most independent predictors of impaired FC. They can be used for risk stratification and as surrogate predictors of outcome in this group of patients.

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.

The value of speckle-tracking echocardiography in identifying right heart dysfunction in patients with chronic thromboembolic pulmonary hypertension

Right ventricular (RV) function is a significantly important factor in the determination of the prognosis of chronic thromboembolic pulmonary hypertension (CTEPH) patients. Speckle-tracking echocardiography (STE) is an angle-independent new technique for quantifying myocardial deformation that is capable of providing data on multiple parameters including longitudinal and transverse information of the myocardium. In the present study, we aimed to study the advantages of STE-derived parameters in identifying RV dysfunction in CTEPH patients. Sixty CTEPH patients (mean age: 55 years ± 13 years; 25 males) and 30 normal controls (mean age: 54 years ± 14 years; 14 males) were enrolled in this study. RV free wall (RVFW) systolic peak longitudinal strain (LS) including the basal, mid-, and apical-segments and the basal longitudinal and transverse displacement (basal-DL and basal-DT) were measured by STE. Global LS (GLS) of the RV was calculated by averaging the LS value of the 3 segments of RVFW. Clinical data of CTEPH patients were collected. CTEPH patients were divided into 2 subgroups according to the World Health Organization function classification. Clinical right heart failure (RHF) was defined as the presence of symptoms of heart failure and signs of systemic circulation congestion during hospitalization. The apical segment LS of the RVFW was lower than that in the basal and mid-segments in the control group (P < 0.001), but no significant difference was found among the 3 segments of LS in the CTEPH group (P = 0.263). When we used the cutoff value recommended by the American Society of Echocardiography guidelines to identify abnormal RV function, 30 CTEPH patients (50%) by tricuspid annular plane systolic excursion (TAPSE), 42 patients (70%) by fractional area change (FAC), 20 patients (33.33%) by RV index of myocardial performance (RVIMP), and 46 patients (77%) patients by GLS were determined to have abnormal RV function, respectively. Among multiple RV function indicators, TAPSE, FAC, GLS, basal-DL, and N-terminal pronatriuretic B-type natriuretic peptide showed significant differences between CTEPH patients with mild (WHO II) and severe symptoms (WHO III/IV) (all P < 0.001), while RVIMP and basal-DT showed no significant difference (P = 0.188 and P = 0.394, respectively). Pearson correlation analysis showed that GLS has no correlation with sPAP as evaluated by echocardiography in CTEPH patients (r = - 0.079, P = 0.574), and a weak to moderate correlation with RA area (r = 0.488, P = 0.000), the RV diameter (r = 0.429, P = 0.001), and the RVFW thickness (r = 0.344, P = 0.009). On receiver operating characteristic analysis, GLS has the largest area under the curve to identify RHF when the cutoff value was - 13.45%, the sensitivity was 78.2%, and the specificity was 84.6%, separately. Our study demonstrated that the depression of regional LS of RVFW is more pronounced in the basal and middle segments in CTEPH patients. Also, the longitudinal movement is much more important than the transverse movement when evaluating RV systolic function. As compared with conventional parameters, RVFW GLS showed more sensitivity to identify abnormal RV function and had the largest AUC for identifying RHF. Additionally, GLS showed no correlation with sPAP and a weak correlation with right heart morphological parameters in our CTEPH cohort.

Preliminary results from a nationwide adult cardiology perspective for pulmonary hypertension: RegiStry on clInical outcoMe and sUrvival in pulmonaRy hypertension Groups (SIMURG)

OBJECTIVE

The present study was designed to evaluate the characteristics of pulmonary hypertension (PH) and adult cardiology practice patterns for PH in our country.

METHODS

We evaluated preliminary survey data of 1501 patients with PH (females, 69%; age, 44.8±5.45) from 20 adult cardiology centers (AdCCs).

RESULTS

The average experience of AdCCs in diagnosing and treating patients with PH was 8.5±3.7 years. Pulmonary arterial hypertension (PAH) was the most frequent group (69%) followed by group 4 PH (19%), group 3 PH (8%), and combined pre- and post-capillary PH (4%). PAH associated with congenital heart disease (APAH-CHD) was the most frequent subgroup (47%) of PAH. Most of the patients' functional class (FC) at the time of diagnosis was III. The right heart catheterization (RHC) rate was 11.9±11.6 per month. Most frequently used vasoreactivity agent was intravenous adenosine (60%). All patients under targeted treatments were periodically for FC, six-minute walking test, and echo measures at 3-month intervals. AdCCs repeated RHC in case of clinical worsening (CW). The annual rate of hospitalization was 14.9±19.5. In-hospital use of intravenous iloprost reported from 16 AdCCs in CWs. Bosentan and ambrisentan, as monotreatment or combination treatment (CT), were noted in 845 and 28 patients, respectively, and inhaled iloprost, subcutaneous treprostinil, and intravenous epoprostenol were noted in 283, 30, and four patients, respectively. Bosentan was the first agent used for CT in all AdCCs and iloprost was the second. Routine use of antiaggregant, anticoagulant, and pneumococcal and influenza prophylaxis were restricted in only two AdCCs.

CONCLUSION

Our nationwide data illustrate the current status of PH regarding clinical characteristics and practice patterns.

Added clinical value of applying myocardial deformation imaging to assess right ventricular function

Right heart dysfunction has been found to be a strong prognostic factor predicting adverse outcome in various cardiopulmonary diseases. Conventional echocardiographic measurements can be limited by geometrical assumptions and impaired reproducibility. Speckle tracking-derived strain provides a robust quantification of right ventricular function. It explicitly evaluates myocardial deformation, as opposed to tissue Doppler-derived strain, which is computed from tissue velocity gradients. Right ventricular longitudinal strain provides a sensitive tool for detecting right ventricular dysfunction, even at subclinical levels. Moreover, the longitudinal strain can be applied for prognostic stratification of patients with pulmonary hypertension, pulmonary embolism, and congestive heart failure. Speckle tracking-derived right atrial strain, right ventricular longitudinal strain-derived mechanical dyssynchrony, and three-dimensional echocardiography-derived strain are emerging imaging parameters and methods. Their application in research is paving the way for their clinical use.

Clinical study of right ventricular longitudinal strain for assessing right ventricular dysfunction and hemodynamics in pulmonary hypertension

This study aimed to appraise the application of right ventricular longitudinal strain for assessing right ventricular dysfunction and severe hemodynamic changes in pulmonary hypertension. The study included 53 patients clinically diagnosed with PH. Tissue Doppler-derived tricuspid lateral annular systolic velocity (s'), early diastolic peak velocity (e'), late diastolic peak velocity (a'), tricuspid annular plane systolic excursion (TAPSE), RV index of myocardial performance (RIMP), and right ventricular fractional area change (FAC) were determined. The STI parameter was RV free wall longitudinal peak systolic strain (RV LPSS). The patients were assigned into two groups based on a RV LPSS value of - 19%.RV LPSS, s', TAPSE, RIMP, FAC, a' and e'/a' showed significant differences. PH patients with an RV LPSS≥ -19% exhibited a lower RV function (P < 0.05). RV LPSS was negatively correlated with TAPSE (r = -0.326, P < 0.05) and FAC (r = -0.495, P < 0.001) and positively correlated with RIMP (r = 0.508, P < 0.001). The optimal cut-off value of RV LPSS to reveal an mPAP ≥ 45 mmHg defined based on the receiver operating characteristic curve analysis was - 19.26% with a sensitivity of 83.9% and a specificity of 73.4%.Distinguishing the degree of RV dysfunction by 2D-STI may help physicians to determine the state of cardiac function and degree of PH in patients and offer a basis for subsequent clinical diagnosis and therapy. Our study demonstrates the superiority of RV LPSS for uncovering severe PH over the traditional echocardiographic parameters.

Nonalcoholic Steatohepatitis Score is an Independent Predictor of Right Ventricular Dysfunction in Patients with Nonalcoholic Fatty Liver Disease

OBJECTIVE

Nonalcoholic fatty liver disease (NAFLD) is associated with increased risk of cardiovascular disease and impaired left ventricular (LV) function, yet the impact of NAFLD on right ventricular (RV) function remains unclear. We investigate the RV functional properties in patients with NAFLD.

METHODS

Ninety consecutive patients with the diagnosis of biopsy-proven NAFLD and 45 age- and sex-matched controls were included. All patients underwent an echocardiographic examination. RV function was evaluated by two-dimensional (2D) speckle-tracking echocardiography (STE).

RESULTS

Mean fibrosis stage and nonalcoholic steatohepatitis (NASH) scores were 1.3 ± 1.1 and 5.2 ± 1.6, respectively. NAFLD patients displayed decreased RV function compared to controls. NAFLD patients with liver fibrosis (67 patients) had significantly lower RV function assessed by GLS (global longitudinal strain) compared to patients without liver fibrosis (18.9 ± 3.4% vs. 21.6 ± 2.3%, P < 0.001). NASH score ≥5 was associated with lower RV-GLS (18.9 ± 3.1% vs. 21.0 ± 3.4%, P = 0.006). NASH score inversely correlated with RV-GLS (r = -0.370, P < 0.001) such as patients with impaired RV-GLS (<19%) showed significantly higher NASH score compared to normal RV-GLS group (5.8 ± 1.4 vs. 4.8 ± 1.7, P = 0.009). Logistic regression analysis revealed that NASH score was an independent predictor of impaired RV function in patients with NAFLD.

CONCLUSIONS

Patients with NAFLD have impaired RV function. NASH score inversely correlates with RV-GLS and independently predicts impaired RV function in patients with NAFLD.

Right and left heart dysfunction predict mortality in pulmonary hypertension

In pulmonary hypertension (PH), the right heart dysfunction is a strong predictor of adverse clinical outcome, while the role of the left heart is not fully determined. The aim of this study was to identify predictors of mortality in precapillary PH including measures of both right and left heart function. We studied 34 patients (mean age 64 ± 13, range 31-82 years, 24 females) with precapillary PH, all of whom underwent detailed Doppler echocardiographic examination of the right and left heart function using conventional and speckle-tracking echocardiography. Patients were followed up for up to 8 years (mean 4·2 ± 1·9 years). At follow-up, 16 patients survived. Left ventricular (LV) filling time (P = 0·007), pulmonary artery acceleration time (P = 0·009), right atrial pressure (RAP) (P<0·001) and tricuspid regurgitation (TR) severity (P = 0·007) were worse in the deceased group. RV global longitudinal strain (GLS) (P = 0·001), RAP (P≤0·001), LV filling time (P<0·001) and TR severity (P<0·001) were the most accurate predictors, having the largest AUC (>0·65) and carried the highest risk for mortality (P<0·001 for all). The strongest predictors of mortality in precapillary PH indirectly reflect both left and right heart dysfunction including atrial structure and function disturbances. While an interaction pattern is observed, it needs to be confirmed in a larger cohort.

Role of strain imaging in right heart disease: a comprehensive review

Advances in the imaging techniques of the heart have fueled the interest in understanding of right heart pathology. Recently, speckle tracking echocardiography has shown to aid in understanding various right heart diseases and better management. Its role is well established in diagnosing right heart failure, pulmonary artery hypertension, arrhythmogenic right ventricular dysplasia and congenital heart disease. We review the basic mechanics of speckle tracking and analyze its role in various right heart conditions.

Right ventricular function in hypertrophic cardiomyopathy: A speckle tracking echocardiography study

Objective:

The aim of this study was to explore right ventricular (RV) mechanical function in patients with hypertrophic cardiomyopathy (HCM) by 2-D speckle tracking echocardiography (2-D-STE).

Methods:

Forty-three patients with HCM (mean age 48, 17 females) and 40 healthy subjects were consecutively included in this cross-sectional study. The diagnosis of HCM was based on the presence of typical clinical, electrocardiographic (ECG), and echocardiographic features. Patients with LV systolic impairment, significant valvular disease, history of coronary artery disease, hypertension, malignancy, and chronic obstructive pulmonary disease were excluded. Right and left ventricular (LV) function was assessed by tissue Doppler imaging (TDI) and 2-D-STE. Hypertrophic cardiomyopathy patients were divided into two groups according to ACC/ESC guidelines (LVOT gradient below and above 30 mm Hg). Student t-test was used to compare differences between groups. Non-parametric tests (Mann-Whitney U) were used in cases of abnormal distribution.

Results:

Hypertrophic cardiomyopathy patients had a significantly larger right atrium and RV diameters compared to controls. Mean pulmonary artery pressures (mPAB) were significantly higher in HCM patients (19.01±13.09 mm Hg vs. 8.40±4.50 mm Hg; p<0.001). Although RV Sm measure-ments were similar, RV strain measurements (-28.51±5.36% vs. -32.06±7.65%; p=0.016) were significantly lower in HCM patients. Left ventricular global longitudinal, radial, and circumferential strain values were also significantly different between the two groups (-20.50±3.58% vs. -24.12±3.40%; p<0.001, 38.18±12.67% vs. 44.80±10.15%; p=0.012, -21.94±4.28% vs. -23.91±3.95%; p=0.036 consecutively). Rotational movement of LV in each apical, mid-, and basal left ventricular segment was determined, and only mid-ventricular rotation of the HCM patients was more clockwise (-1.71±2.16 ° vs. 0.04±1.72 p<0.001). Although mPAP measurements were higher in HCM patients with significant LVOT obstruction (21.52±13.26 mm Hg vs. 12.31±10.53 mm Hg; p=0.049), none of the other TDI or 2-D-STE parameters was significantly different between groups.

Conclusion:

Speckle tracking echocardiography-derived right ventricular systolic function is impaired in HCM patients when compared with healthy subjects. However, RV systolic function is not affected form LVOT obstruction and left ventricular rotation dynamics in HCM patients.