Echocardiography in pulmonary arterial hypertension: from diagnosis to prognosis

Natural Course of Adult Ebstein Anomaly When Treated according to Current Recommendation

The objectives of this study were to assess the clinical outcomes of adults with Ebstein Anomaly (EA) according to their treatment modalities. All adult EA patients diagnosed between October 1994 and October 2014 were retrospectively evaluated by medical record review. Total 60 patients were categorized into 3 groups according to their treatment strategy, i.e. non-operative treatment (Group I, n = 23), immediate operative treatment (Group II, n = 27), and delayed operative treatment (Group III, n = 10). A composite of major adverse cardiac and cerebrovascular events (MACCE) and factors associated with MACCE were assessed in each treatment group. MACCE occurred in 13.0% patients in Group I, 55.6% patients in Group II and 50% in Group III (P = 0.006). Event free survivals at 5 years were 90% in Group I, 52.7% in Group II, 50.0% in Group III (P = 0.036). Post-operatively, most patients showed improvement on clinical symptoms. However, event free survival rate was lower in patients with operation compared to those with non-operative treatment (58.7% vs. 90.9%; P = 0.007). Major arrhythmic event occurred more frequently even after surgical ablation (50.0% vs. 20.0%; P = 0.034). Re-operation was more frequent in patients underwent delayed surgery compared to those with immediate surgery (50.0% vs. 18.5%; P = 0.001). Current guideline to decide patient's treatment strategy appeared to be appropriate in adult patients with EA. However, surgical ablation for arrhythmia was not enough so that concomitant medical treatment should be considered. Therefore, attentive risk stratification and cautious decision of treatment strategy by experienced cardiac surgeon are believed to improve clinical outcome.

Reference ranges and determinants of right ventricle outflow tract acceleration time in healthy adults by two-dimensional echocardiography

The right ventricular outflow tract acceleration time (RVOT-AT) has shown to progressively shorten with increasing degrees of pulmonary pressure. However, the physiologic ranges of RVOT AT are based on small sample sizes and have not been investigated regarding their determining factors. The aim of this study was to investigate reference values and determining factors of RVOT-AT in a large population of healthy subjects and by values described in the literature. In the first part of the study, 1029 healthy subjects (mean age 45.6 ± 16.0 years, 565 (54.7 %) females) were prospectively assessed by clinical examination including demography, vital signs and echocardiography. In the second part, we performed a pooled analysis of eight published studies describing RVOT-AT in healthy subjects (n = 450). Statistical analysis included the calculation of 5 % quantiles for defining reference values. RVOT-AT significantly but weakly correlated with age (r: -0.207; p < 0.001), body mass Index (r: -0.16), systolic (r: -0.158) and diastolic (r: -0.137) blood pressure, heart rate (r: -0.197) and left ventricular (LV) E/A ratio (r: 0.229) (all p < 0.001). No differences were found with regards to sex. In a synopsis of both prospective and literature-based data sets, RVOT-AT weighted means was 138.51 ms and the 5 % quantile was 104.7 ms (95 % confidence interval 98.2-110.1). This study delineates the range of RVOT-AT in healthy adults and it's determining factors. Our study is in line with the cut-off value stated by the European guidelines with an RVOT-AT ≤105 ms denoting abnormal values.

Physiologic correlates of tricuspid annular plane systolic excursion in 1168 healthy subjects

BACKGROUND

TAPSE provides a simple, reproducible estimate of the longitudinal function of the right ventricle (RV). However, the normal limits and physiologic correlates of tricuspid annular plane systolic excursion (TAPSE) are not exactly known. The aim of this study was to explore the full spectrum of TAPSE values and determine the physiologic correlates of TAPSE.

METHODS AND RESULTS

From June 2007 to December 2013, 1168 healthy subjects [mean age 45.1±16years, range 16 to 92; 555 (47.5%) men] underwent comprehensive transthoracic echocardiography (TTE) as recommended by current guidelines. TAPSE values were higher in men than women (24.0±3.5 vs 23.2±3.0mm, p value<0.0001) but did not vary according to age. On multivariable linear regression analysis, cardiac output, RV basal and longitudinal dimensions were the only variables independently associated with TAPSE (β coefficient=0.161, 0.116 and 0.115 respectively). On the other hand echocardiographically-derived systolic pulmonary artery pressure (SPAP), pulmonary vascular resistance and mitral E/e' ratio were significantly higher in older subjects. Therefore a significant decrease of TAPSE/SPAP was detected in >60years old cohort (p=0.0001).

CONCLUSIONS

Our large cohort of healthy subjects provides sex and age-based TAPSE and TAPSE/SPAP normal cut-offs. TAPSE was found to be higher in men but not influenced by age. It was mainly correlated with echo-Doppler indices reflecting pre-load as opposed to afterload. On the other hand a significant decrease of TAPSE/SPAP with older age was registered as a direct consequence of increased SPAP with aging.

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.

Echocardiography in pulmonary hypertension

PURPOSE OF REVIEW

Pulmonary hypertension is a progressive disease of the pulmonary vasculature characterized by increased vascular resistance and pressure overload of the right ventricle. This review aims to describe the diagnostic and prognostic role of echocardiography in pulmonary hypertension with particular consideration of relative strengths, weaknesses and new advances.

RECENT FINDINGS

Although right heart catheterization (RHC) remains the gold standard, echocardiography represents an accessible and feasible real-world tool for screening, differential diagnostic, follow-up assessments and risk stratification in pulmonary hypertension. In the context of clinical scenario and multimaging approach, echocardiography provides accurate measurements of pulmonary haemodynamics, either at rest and/or during exercise, and is particularly useful in ruling out secondary causes of pulmonary hypertension and/or detecting preclinical stages. The use of advanced noninvasive imaging techniques may provide additional information in assessing right heart structure and function.

SUMMARY

Advances in echocardiography and the multimodality imaging approach continue to provide new understandings and opportunities for the study of the right heart-pulmonary circulation unit in pulmonary hypertension.

Acute and Chronic Effects of Noninvasive Ventilation on Left and Right Myocardial Function in Patients with Obstructive Sleep Apnea Syndrome: A Speckle Tracking Echocardiographic Study

BACKGROUND

In patients with obstructive sleep apnea syndrome (OSAS), repetitive hypoxia due to sleep-induced apnea adversely affects the interaction between myocardial oxygen demand and supply, resulting in the development of subclinical cardiac dysfunction. The purpose of the study was to analyze the different involvement of left and right heart myocardial function in patients with OSAS treated with noninvasive ventilation (NIV).

METHODS

Conventional Doppler echocardiography, Doppler myocardial imaging (DMI), and two-dimensional speckle tracking echocardiography (2DSTE) of left (LV) and right ventricular (RV) longitudinal and right atrial (RA) deformation were performed in 55 patients with OSAS undergoing NIV (M/F 38/17; mean age 67.8 ± 11.2 years). LV and RV global longitudinal strain (GLS) was calculated by averaging local strain along the entire right and left ventricle, before and during NIV, and after 6 months of nocturnal NIV therapy.

RESULTS

LV morphology was comparable before and during NIV, whereas LV ejection fraction and LV DMI early diastolic peak velocity were significantly improved in patients with OSAS during NIV, as was LV regional peak myocardial strain (P < 0.001). RV diameters were slightly increased in patients with OSAS during ventilation, whereas pulmonary artery systolic pressure (PASP), RV GLS, and regional peak myocardial RV strain were significantly reduced during ventilation (P < 0.0001). RA transverse diameters and RA area were also slightly increased during NIV, whereas RA lateral wall strain was reduced (P < 0.001). Acute RV myocardial impairment completely reversed at follow-up, with a decrease in PASP and subsequent increase in both RV and RA myocardial performance.

CONCLUSIONS

Conventional 2DSTE is a useful tool for assessing left and right heart morphology and myocardial deformation in patients with OSAS and for monitoring both acute and chronic effects of NIV.

Left Ventricular Function in Patients with Pulmonary Arterial Hypertension: The Role of Two-Dimensional Speckle Tracking Strain

BACKGROUND

Pulmonary arterial hypertension (PAH) is characterized by elevated mean pulmonary arterial pressure with abnormal right ventricular (RV) pressure overload that may alter left ventricular (LV) function. The aim of this study was to assess the impact of RV pressure overload on LV function in PAH patients using two-dimensional (2D) speckle tracking strain.

METHODS

The study enrolled 37 group 1 PAH patients and 38 age- and gender-matched healthy controls. LV longitudinal and radial 2D strains were measured with and without including the ventricular septum. Six-minute walk test (6MWT) and brain natriuretic peptide (BNP) levels were also obtained in patients with PAH.

RESULTS

The mean age of patients was 46.4 ± 14.8 years, 76% women, and 16 patients (43%) had schistosomiasis. Sixteen patients (43%) were in WHO class III or IV under specific treatment for PAH. The overall 6MWT distance was 441 meters, and the BNP levels were 80 pg/mL. Patients with PAH more commonly presented with LV diastolic dysfunction and impairment of RV function when compared to controls. LV global longitudinal and radial strains were lower in patients than in controls (-17.9 ± 2.8 vs. -20.5 ± 1.9; P < 0.001 and 30.8 ± 10.5 vs. 49.8 ± 15.4; P < 0.001, respectively). After excluding septal values, LV longitudinal and radial strains remained lower in patients than in controls. The independent factors associated with global LV longitudinal strain were LV ejection fraction, RV fractional area change, and tricuspid annular systolic motion.

CONCLUSIONS

This study showed impaired LV contractility in patients with PAH assessed by speckle tracking strain, irrespective of ventricular septal involvement. Global LV longitudinal strain was associated independently with RV fractional area change and tricuspid annular systolic motion, after adjustment for LV ejection fraction.

Assessment of pulmonary artery pressure by echocardiography-A comprehensive review

Pulmonary hypertension is a pathological haemodynamic condition defined as an increase in mean pulmonary arterial pressure ≥ 25 mmHg at rest, assessed using gold standard investigation by right heart catheterisation. Pulmonary hypertension could be a complication of cardiac or pulmonary disease, or a primary disorder of small pulmonary arteries. Elevated pulmonary pressure (PAP) is associated with increased mortality, irrespective of the aetiology. The gold standard for diagnosis is invasive right heart catheterisation, but this has its own inherent risks. In the past 30 years, immense technological improvements in echocardiography have increased its sensitivity for quantifying pulmonary artery pressure (PAP) and it is now recognised as a safe and readily available alternative to right heart catheterisation. In the future, scores combining various echo techniques can approach the gold standard in terms of sensitivity and accuracy, thereby reducing the need for repeated invasive assessments in these patients.

•

Raised artery pulmonary pressure (PAP) is associated with increased mortality.

•

We review the eight published echo techniques to assess PAP by echocardiography.

•

Knowledge of all the echo techniques could avoid need for invasive tests.

•

A scoring system combining various echo-derived measurements of PAP is needed.

Clinical profile and in-hospital outcome of Caucasian patients with takotsubo syndrome and right ventricular involvement

AIM

To determine the prevalence, clinical characteristics, in-hospital course and determinants of major adverse events in a cohort of Caucasian patients with Takotsubo syndrome (TTS) and right ventricular involvement (RVi), regardless of left ventricular variant forms.

METHODS AND RESULTS

The study population consisted of 424 patients (mean age 69.1±11.5years; female 92.2%) with a diagnosis of TTS divided into two groups according to the presence or absence of RVi. RVi patients (n=57; 13.4%) showed a higher prevalence of comorbidities, especially respiratory diseases (p=0.011), and a higher Charlson comorbidity index (CCI; p=0.006) than non-RVi patients. In-hospital major adverse events (acute heart failure, cardiogenic shock and death) occurred more frequently in RVi patients (p<0.001). Heart rate and CCI, along with the echocardiographic parameters of wall motion score index, E/e' ratio, tricuspid annular plane systolic excursion (TAPSE) and systolic pulmonary artery pressure (sPAP) were associated with adverse in-hospital outcome. At multivariate analysis, CCI (HR: 1.871; 95% CI: 1.202-2.912; p=0.006), sPAP (HR: 1.059; 95% CI: 1.016-1.104; p=0.007) and TAPSE (HR: 0.728; 95% CI: 0.619-0.855; p<0.001) were independent correlates of the composite outcome in patients with RVi.

CONCLUSION

Patients with RVi are characterized by distinct clinical profile and should undergo closely clinical and echocardiographic monitoring. The presence of echocardiographic signs of right ventricular failure along with substantial comorbidities burden identify a cohort at higher risk of in-hospital major adverse cardiovascular events.

Salvianolic acid A attenuates vascular remodeling in a pulmonary arterial hypertension rat model

AIM

The current therapeutic approaches have a limited effect on the dysregulated pulmonary vascular remodeling, which is characteristic of pulmonary arterial hypertension (PAH). In this study we examined whether salvianolic acid A (SAA) extracted from the traditional Chinese medicine 'Dan Shen' attenuated vascular remodeling in a PAH rat model, and elucidated the underlying mechanisms.

METHODS

PAH was induced in rats by injecting a single dose of monocrotaline (MCT 60 mg/kg, sc). The rats were orally treated with either SAA (0.3, 1, 3 mg·kg(-1)·d(-1)) or a positive control bosentan (30 mg·kg(-1)·d(-1)) for 4 weeks. Echocardiography and hemodynamic measurements were performed on d 28. Then the hearts and lungs were harvested, the organ indices and pulmonary artery wall thickness were calculated, and biochemical and histochemical analysis were conducted. The levels of apoptotic and signaling proteins in the lungs were measured using immunoblotting.

RESULTS

Treatment with SAA or bosentan effectively ameliorated MCT-induced pulmonary artery remodeling, pulmonary hemodynamic abnormalities and the subsequent increases of right ventricular systolic pressure (RVSP). Furthermore, the treatments significantly attenuated MCT-induced hypertrophic damage of myocardium, parenchymal injury and collagen deposition in the lungs. Moreover, the treatments attenuated MCT-induced apoptosis and fibrosis in the lungs. The treatments partially restored MCT-induced reductions of bone morphogenetic protein type II receptor (BMPRII) and phosphorylated Smad1/5 in the lungs.

CONCLUSION

SAA ameliorates the pulmonary arterial remodeling in MCT-induced PAH rats most likely via activating the BMPRII-Smad pathway and inhibiting apoptosis. Thus, SAA may have therapeutic potential for the patients at high risk of PAH.

Connective tissue disease-related pulmonary arterial hypertension

Over the past two decades, there have been several advances in the assessment and management of connective tissue disease-related pulmonary arterial hypertension (CTD-PAH) that improved outcomes of the treatment of this lethal disease, and this will be the focus of this study. Systemic sclerosis is the leading cause of CTD-PAH, followed by systemic lupus erythematosus, mixed connective tissue disease, idiopathic inflammatory myositis, rheumatoid arthritis, and Sjogren's syndrome. Clinical registries have been invaluable in informing about the burden of disease, risk and prognostic factors, and temporal trends with respect to treatment and outcome in CTD-PAH. The major advances have centered on improved disease classification and diagnostic criteria, screening and early diagnosis, the emergence of evidence-based therapies including combination goal-orientated treatment strategies, and the establishment of centers with expertise in PAH.

The Evolving Landscape of Exercise-Induced Pulmonary Hypertension

OPINION STATEMENT

Normal pulmonary artery pressures at rest, with an exaggerated rise during exercise, characterize exercise-induced pulmonary hypertension. Exercise itself as it relates to this condition is not deleterious, nor does it cause or induce disease. However much like any classical stress test, it is a physiologic probe that aids in disease unmasking. Although more work is required to establish criteria for defining this clinical entity, the phenomenon is real. It remains unknown whether it represents a nascent form of cardiopulmonary disease and whether its genesis predicts fulminant cardiopulmonary disease. Incremental cardiopulmonary exercise testing and the construction of pressure-flow plots to describe the pulmonary vascular response to exercise will be essential in defining this disease. The critical first step remains a consensus definition that will allow for further prospective study focused by a common language.

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.

Assessment of Right Ventricular Afterload in COPD

BACKGROUND

We aimed to study whether pulmonary hypertension (PH) and elevated pulmonary vascular resistance (PVR) could be predicted by conventional echo Doppler and novel tissue Doppler imaging (TDI) in a population of chronic obstructive pulmonary disease (COPD) free of LV disease and co-morbidities.

METHODS

Echocardiography and right heart catheterization was performed in 100 outpatients with COPD. By echocardiography the time-integral of the TDI index, right ventricular systolic velocity (RVSmVTI) and pulmonary acceleration-time (PAAcT) were measured and adjusted for heart rate. The COPD patients were randomly divided in a derivation (n = 50) and a validation cohort (n = 50).

RESULTS

PH (mean pulmonary artery pressure (mPAP) ≥ 25mmHg) and elevated PVR ≥ 2Wood unit (WU) were predicted by satisfactory area under the curve for RVSmVTI of 0.93 and 0.93 and for PAAcT of 0.96 and 0.96, respectively. Both echo indices were 100% feasible, contrasting 84% feasibility for parameters relying on contrast enhanced tricuspid-regurgitation. RVSmVTI and PAAcT showed best correlations to invasive measured mPAP, but less so to PVR. PAAcT was accurate in 90- and 78% and RVSmVTI in 90- and 84% in the calculation of mPAP and PVR, respectively.

CONCLUSIONS

Heart rate adjusted-PAAcT and RVSmVTI are simple and reproducible methods that correlate well with pulmonary artery pressure and PVR and showed high accuracy in detecting PH and increased PVR in patients with COPD. Taken into account the high feasibility of these two echo indices, they should be considered in the echocardiographic assessment of COPD patients.

Altitude-Induced Pulmonary Hypertension on One-Day Rapid Ascent of Mount Fuji: Incidence and Therapeutic Effects of Sildenafil

AIMS

Exposure to high altitudes especially with rapid ascent may induce hypoxic pulmonary vasoconstriction (HPV) and pulmonary hypertension (PH) possibly leading to life-threatening high-altitude pulmonary edema (HAPE). The aim of the study was to evaluate the incidence of PH on a 1-day rapid ascent up Mount Fuji (3775 m) in recreational climbers and also to determine the effectiveness of sildenafil for this rapid ascent-induced PH as measured by echocardiography.

METHODS AND RESULTS

Twenty-five subjects who climbed Mount Fuji showed significantly increased pulmonary artery systolic pressure (PASP) from 22.3 ± 5.3 mmHg at sea level to 29.4 ± 8.7 mmHg at 3775 m. Five subjects showed PASP >35 mmHg (35.6-46.2 mmHg, average 42.0 ± 3.9 mmHg) and took oral sildenafil 50 mg after which PASP decreased significantly to 24.5 ± 4.6 mmHg (18.7-31.0 mmHg) after 30 minutes.

CONCLUSIONS

One-day rapid ascent of Mount Fuji may induce mild-to-moderate PH and intervention with sildenafil can reduce this PH, suggesting that the therapeutic use of sildenafil would be more reasonable for the relatively infrequent occurrence of altitude-induced PH than its prophylactic use.

Portopulmonary hypertension in liver transplant candidates

Pulmonary vascular disorders including portopulmonary hypertension (PoPHT) are among the common complications of liver disease and are prognostically significant. Survival is very low without medical treatment and liver transplantation. With advances in medical therapy for elevated pulmonary artery pressure (PAP) and liver transplant surgery, survival of patients with PoPHT and advanced liver disease is significantly improved. Because of the prognostic significance of PoPHT and the limited donor pool, a comprehensive preoperative cardio-pulmonary assessment is of great importance in cirrhotic patients prior to transplant surgery. Therefore, a detailed transthoracic Doppler echocardiographic examination must be an essential component of this evaluation. Patients with mild PoPHT can safely undergo liver transplant surgery. In cases of moderate to severe PoPHT, right heart catheterization (RHC) should be performed. In patients with moderate to severe PoPHT on RHC (mean PAP 35-45 mmHg), vasodilator therapy should be attempted. Liver transplantation should be encouraged in cases that demonstrate a positive response. Bridging therapy with specific pulmonary arterial hypertension treatment agents should be considered until the transplant surgery and should be continued during the peri- and post-operative periods as needed.

Right Atrial Function in Pulmonary Arterial Hypertension

BACKGROUND

Elevated right atrial (RA) pressure is an established prognostic measure in pulmonary arterial hypertension (PAH). However, little is known about perturbations in RA function in PAH.

METHODS AND RESULTS

Reservoir (RA longitudinal strain [RA LS]), conduit (RA early LS rate), and active (RA late LS rate) phases were assessed by 2D speckle tracking in 65 patients with PAH, 6-minute walk distance ≤450 m, and a pulmonary vascular resistance >800 dynes·s/cm(5), despite therapy with at least 2 PAH-specific medications enrolled in the Imatinib in Pulmonary Arterial Hypertension, a Randomized Efficacy Study (IMPRES) trial and were compared with 30 healthy controls of similar age and sex. We studied the association of RA functional measures with invasive pulmonary hemodynamics, cardiac structure and function, and N-terminal pro brain natriuretic peptide. RA LS and early LS rate were reduced in PAH patients compared with controls (27.1±11.6 versus 56.9±12.7, adjusted P<0.001 and -0.6±0.5 versus -1.5±0.5, adjusted P<0.001, respectively) even after adjusting for RA area and invasive RA pressure, whereas RA late LS rate was similar between groups (-1.4±0.7 versus -1.5±0.4, P=0.42). Among PAH patients, worse RA LS correlated with greater RA size (r=-0.50, P<0.0001) and pressure (r=-0.37, P=0.002), but not pulmonary artery pressure (r=-0.07, P=0.58). Worse RA LS was also associated with right ventricular enlargement and dysfunction and higher N-terminal pro brain natriuretic peptide independent of RA size and pressure.

CONCLUSIONS

RA reservoir and passive conduit functions are impaired in PAH, independent of RA size and pressure, and likely reflect right ventricular failure and overload.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00902174.

Right Ventricular Structure and Function in Idiopathic Pulmonary Fibrosis with or without Pulmonary Hypertension

Aims

To elucidate right ventricular (RV) function in patients with idiopathic pulmonary fibrosis (IPF) with and without pulmonary hypertension (PH) and its relation to other features of the disease.

Methods and Results

Clinical evaluation, standard Doppler echo, Doppler myocardial imaging (DMI), and 2D strain echocardiography (STE) of RV septal and lateral walls were performed in 52 IPF patients (66.5 ± 8.5 years; 27 males) and in 45 age‐ and sex‐comparable controls using a commercial US system (MyLab Alpha, Esaote). Pulmonary artery mean pressure (mPAP) was estimated by standard echo Doppler. RV global longitudinal strain (RV GLS) was calculated by averaging RV local strains. The IPF patients were divided into 2 groups by noninvasive assessment of PH: no PH (mPAP<25 mmHg; 36 pts) and PH (mPAP ≥25 mmHg; 16 pts). Left ventricular diameters and ejection fraction were comparable between controls and IPF, while GLS was impaired in IPF (P < 0.01). RV end‐diastolic diameters, wall thickness andmPAP were increased in IPF patients with PH. In addition, pulsed DMI detected in PH IPF impaired myocardial RV early diastolic (Em) peak velocity. Also peak systolic RV strain was reduced in basal and middle RV lateral free walls in IPF, as well as RV GLS (P < 0.0001). The impairment in RV wall strain was more evident when comparing controls with the no PH group than comparing the no PH group with the PH group. By multivariate analysis, independent association of RV strain with both six‐minute walking test distance (P < 0.001), mPAP (P < 0.0001), as well as with forced vital capacity (FVC) % (P < 0.005) in IPF patients were observed.

Conclusions

Impaired RV diastolic and systolic myocardial function were present even in IPF patients without PH, which indicates an early impact on RV function and structure in patients with IPF.

Clinical Application of Superior Vena Cava Spectra in Evaluation of Pulmonary Hypertension: A Comparative Echocardiography and Catheterization Study

This study was designed to assess whether superior vena cava (SVC) Doppler flow velocities are associated with invasive measures of pulmonary arterial pressure. Eighty patients with unrepaired congenital heart disease who underwent cardiac catheterization were included (31 men, 49 women; mean age: 37.3 ± 14.7 y). Compared with the non-pulmonary hypertension group, the moderate and severe pulmonary hypertension groups had decreased SVC ventricular reserve flow velocity and a significantly increased ratio of atrial reverse flow to systolic flow (AR/S). AR/S correlated significantly with invasive pulmonary arterial systolic pressure (r = 0.426, p < 0.0001). A cutoff of 0.45 had a sensitivity and specificity of 74% and 80%, respectively, for prediction of pulmonary hypertension. Good correlation also existed between SVC AR/S and pulmonary arterial systolic pressure in cases without tricuspid regurgitation (r = 0.706, p = 0.034). These results indicate that SVC AR/S may be an alternative method for assessing pulmonary hypertension.

Association of Apical Longitudinal Rotation with Right Ventricular Performance in Patients with Pulmonary Hypertension: Insights into Overestimation of Tricuspid Annular Plane Systolic Excursion

BACKGROUND

Current guidelines recommend the routine use of tricuspid annular plane systolic excursion (TAPSE) as a simple method for estimating right ventricular (RV) function. However, when ventricular apical longitudinal rotation (apical-LR) occurs in pulmonary hypertension (PH) patients, it may result in overestimated TAPSE.

METHODS

We studied 105 patients with PH defined as mean pulmonary artery pressure >25 mmHg at rest measured by right heart cardiac catheterization. TAPSE was defined as the maximum displacement during systole in the RV-focused apical four-chamber view. RV free-wall longitudinal speckle tracking strain (RV-free) was calculated by averaging 3 regional peak systolic strains. The apical-LR was measured at the peak rotation in the apical region including both left and right ventricle. The eccentricity index (EI) was defined as the ratio of the length of 2 perpendicular minor-axis diameters, one of which bisected and was perpendicular to the interventricular septum, and was obtained at end-systole (EI-sys) and end-diastole (EI-dia). Twenty age-, gender-, and left ventricular ejection fraction-matched normal controls were studied for comparison.

RESULTS

The apical-LR in PH patients was significantly lower than that in normal controls (-3.4 ± 2.7° vs. -1.3 ± 1.9°, P = 0.001). Simple linear regression analysis showed that gender, TAPSE, EI-sys, and EI-dia/EI-sys were associated with apical-LR, but RV-free was not. Multiple regression analysis demonstrated that gender, EI-dia/EI-sys, and TAPSE were independent determinants of apical-LR.

CONCLUSIONS

TAPSE may be overestimated in PH patients with clockwise rotation resulting from left ventricular compression. TAPSE should thus be evaluated carefully in PH patients with marked apical rotation.

Rest and exercise echocardiography for early detection of pulmonary hypertension

Early detection of pulmonary hypertension (PH) is essential to ensure that patients receive timely and appropriate treatment for this progressive disease. Rest and exercise echocardiography has been used to screen patients in an attempt to identify early stage PH. However, current PH guidelines recommend against exercise tests because of the lack of evidence. We reviewed previous studies to discuss the current standpoint concerning rest and exercise echocardiography in PH. Around 20 exercise echocardiography studies were included to assess the cutoff value for exercise-induced pulmonary hypertension (EIPH). Approximately 40 exercise echocardiography studies were also included to evaluate the pulmonary artery pressure-flow relationship as assessed by the slope of the mean pulmonary artery pressure and cardiac output (ΔmPAP/ΔQ). There were several EIPH and ΔmPAP/ΔQ reference values in individuals with pulmonary vascular disease. We believed that assessing the ΔmPAP/ΔQ makes sense from a physiological standpoint, and the clinical value should be confirmed in future studies. Exercise echocardiography is an appealing alternative in PH. Further studies are needed to assess the prognostic value of the pulmonary artery pressure-flow relationship in high-risk subjects.

Essential echocardiographic evaluation in patients with suspected pulmonary hypertension: an overview for the practicing physician

Prompt and accurate diagnosis of patients presenting with symptoms suggestive of pulmonary arterial hypertension (PAH) is of outmost importance as delays in identifying this clinical entity have detrimental effects on both morbidity and mortality. Initial noninvasive assessment of these patients has traditionally included a number of routine tests of which transthoracic echocardiography (TTE) has been shown to either confirm the presence of structural anomalies of the right ventricle (RV) indicative of PAH or exclude other potential causes of pulmonary hypertension (PH). Consequently, TTE has become a well-validated and readily available imaging tool not only used for this initial screening but also for routine follow-up of PH patients. Since chronic PH is known to unbalance the normal hemodynamic and mechanical homeostatic interaction between the RV and pulmonary circulation; the resulting response is that of an abnormal RV remodeling, clinically translated into progressive RV hypertrophy and dilatation. An enlarged and hypertrophied RV not only would eventually lose effective contractility but also this gradual decline in RV systolic function is the main abnormality in determining adverse clinical outcomes. Therefore, it is of outmost importance that TTE examination be comprehensive but most importantly accurate and reproducible. This review aims to highlight the most important objective measures that can be routinely employed, without added complexity, that will certainly enhance the interpretation and advance our understanding of the hemodynamic and mechanical abnormalities that PH exerts on the RV.

Imaging the heart in pulmonary hypertension: an update

Noninvasive imaging of the heart plays an important role in the diagnosis and management of pulmonary hypertension (PH), and several well-established techniques are available for assessing performance of the right ventricle, the key determinant of patient survival. While right heart catheterisation is mandatory for establishing a diagnosis of PH, echocardiography is the most important screening tool for early detection of PH. Cardiac magnetic resonance imaging (CMRI) is also a reliable and practical tool that can be used as part of the diagnostic work-up. Echocardiography can measure a range of haemodynamic and anatomical variables (e.g. pericardial effusion and pulmonary artery pressure), whereas CMRI provides complementary information to echocardiography via high-resolution, three-dimensional imaging. Together with echocardiography and CMRI, techniques such as high-resolution computed tomography and positron emission tomography may also be valuable for screening, monitoring and follow-up assessments of patients with PH, but their clinical relevance has yet to be established. Technological advances have produced new variants of echocardiography, CMRI and positron emission tomography, and these permit closer examination of myocardial architecture, motion and deformation. Integrating these new tools into clinical practice in the future may lead to more precise noninvasive determination of diagnosis, risk and prognosis for PH.

The Role of Echocardiography in the Evaluation of Pulmonary Arterial Hypertension

The evaluation of pulmonary arterial hypertension (PAH) requires a multimodality approach that combines invasive and noninvasive imaging studies to ensure accurate diagnosis and classification. Given the complexity of the hemodynamic relationships between the left heart, pulmonary circulation, and right heart, the diagnosis of PAH is often a challenging task. Right heart catheterization is the gold standard for diagnosis, providing the hemodynamic information that defines the disease. Nonetheless, echocardiography continues to be a valuable tool in the approach to the patient with suspected PAH. Echocardiographic assessment generates a wealth of information about the response of the right heart to elevated pulmonary pressures and provides essential diagnostic and prognostic data to the clinician. Numerous measurements can be used to identify alterations in right heart morphology, pressure, and function; although each variable in isolation may have little utility, meaningful information is revealed when multiple parameters are considered together. In this article, we will review the echocardiographic measurements employed in assessment of the right heart and seek to clarify the role of echocardiography in the diagnostic workup of PAH.

The frequency of pulmonary hypertension in patients with juvenile scleroderma

Juvenile scleroderma (JS) represents a rarely seen group of connective tissue diseases with multiple organ involvement. Cardiac involvement in JSS is well known and, although rare in children, it may be an important cause of mortality and morbidity. Therefore, an early determination of cardio-vascular and pulmonary involvement is of the most relevance to reduce the mortality in patients with juvenile scleroderma. The aim of the study was to explore the non-invasive methods (Doppler echocardiography, pulmonary function tests), Forced vital capacity (FVC) and Carbon monoxide diffusion capacity (DLCO) in the assessment of the cardiopulmonary involvement in patients with JS. The assessment of pulmonary arterial pressure (PAP) and risk factors for pulmonary arterial hypertension (PAH) were made by the measurement of maximum tricuspid insufficiency (TI), end-diastolic pulmonary insufficiency (PI), ratio of acceleration time (AT) to ejection time (ET) (AT/ET), right atrial pressure (RAP) and contraction of vena cava inferior during inspiration. Thirty-five patients with confirmed JS were included in the study. The mean age of onset of the disease was 9.57 years (median 10 years, range 2-18 years). The mean disease duration and follow-up time was 2 years (median 1 year, range 0.5-8 years) and 3.57 years (median 2 years, range 0.5-14.5 years), respectively.The values of all the analyzed parameters including TI, PI, AT/ET, PAP, FVC and DLCO were found to be within normal ranges in all the patients tested, confirming an uncommonness of cardiopulmonary involvement in patients with juvenile scleroderma.

Pulmonary hypertension trials: how can we do better?

Conducting clinical trials on pulmonary hypertension in the US and Western Europe has become increasingly difficult and costly because of many challenges. These include a limited patient population that makes recruitment difficult. Recruiting internationally has helped, but can add variability. The choice of end points is important but ideal end points that reflect pathogenesis of the disease are not available. The 6-min walk distance has been used in most trials to date, but recent trials have used an 'event-driven' design, in which combined outcomes are used to reflect progression of the disease. This design has advantages but requires many hundreds of patients and may take up to several years. Thus, there is still a role for functional or hemodynamic end points to enable testing of more new agents. Assuring the safety and scientific integrity of clinical trials without excessive regulation will also help facilitate the evaluation of additional therapies for this devastating disease.

Exercise training improves peak oxygen consumption and haemodynamics in patients with severe pulmonary arterial hypertension and inoperable chronic thrombo-embolic pulmonary hypertension: a prospective, randomized, controlled trial

Aims

The impact of exercise training on the right heart and pulmonary circulation has not yet been invasively assessed in patients with pulmonary hypertension (PH) and right heart failure. This prospective randomized controlled study investigates the effects of exercise training on peak VO₂/kg, haemodynamics, and further clinically relevant parameters in PH patients.

Methods and results

Eighty-seven patients with pulmonary arterial hypertension and inoperable chronic thrombo-embolic PH (54% female, 56 ± 15 years, 84% World Health Organization functional class III/IV, 53% combination therapy) on stable disease-targeted medication were randomly assigned to a control and training group. Medication remained unchanged during the study period. Non-invasive assessments and right heart catheterization at rest and during exercise were performed at baseline and after 15 weeks. Primary endpoint was the change in peak VO₂/kg. Secondary endpoints included changes in haemodynamics. For missing data, multiple imputation and responder analyses were performed. The study results showed a significant improvement of peak VO₂/kg in the training group (difference from baseline to 15 weeks: training +3.1 ± 2.7 mL/min/kg equals +24.3% vs. control −0.2 ± 2.3 mL/min/kg equals +0.9%, P < 0.001). Cardiac index (CI) at rest and during exercise, mean pulmonary arterial pressure, pulmonary vascular resistance, 6 min walking distance, quality of life, and exercise capacity significantly improved by exercise training.

Conclusion

Low-dose exercise training at 4–7 days/week significantly improved peak VO₂/kg, haemodynamics, and further clinically relevant parameters. The improvements of CI at rest and during exercise indicate that exercise training may improve the right ventricular function. Further, large multicentre trials are necessary to confirm these results.

Echocardiography in the evaluation of athletes

Echocardiography is currently a widely available imaging technique that can provide useful data in the field of sports cardiology particularly in two areas: pre-participation screening and analysis of the cardiac adaptation induced by exercise.

The application of pre-participation screening and especially, the type and number of used diagnostic tests remains controversial. Echocardiography has shown though, higher sensitivity and specificity as compared to the ECG, following a protocol adapted to athletes focused on ruling out the causes of sudden death and the most common disorders in this population. It is still a subject of controversy the actual cost of adding it, but depending on the type of sport, echocardiography might be cost-effective if added in the first line of examination.

Regarding the evaluation of cardiac adaptation to training in athletes,  echocardiography has proved to be useful in the differential diagnosis of diseases that can cause sudden death, analysing both the left ventricle (hypertrophy cardiomyopathy, dilated cardiomyopathy, left ventricle non compaction) and the right ventricle (arrhythmogenic right ventricular cardiomyopathy).

The aim of this paper is to review the current knowledge and the clinical practical implications of it on the field of echocardiography when applied in sport cardiology areas.

Change of right heart size and function by long-term therapy with riociguat in patients with pulmonary arterial hypertension and chronic thromboembolic pulmonary hypertension

BACKGROUND

Riociguat is a soluble guanylate cyclase stimulator approved for pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTEPH). The objective of this study was to evaluate the change of right heart size and function assessed by echocardiography during long-term treatment with riociguat.

METHODS

We assessed patients who started riociguat treatment (1.0-2.5mg tid) within the trials PATENT, PATENTplus, EAS and CHEST and continued for 3-12 months. Echocardiography, 6-minute walking distance (6MWD) and further clinical parameters were analyzed at baseline, after 3, 6 and 12 months. Right heart catheterization was performed at baseline and after 3 months. For missing data we performed the last and baseline observation carried forward (LOCF, BOCF) method as sensitivity analyses.

RESULTS

Thirty-nine patients (21 PAH, 18 CTEPH, mean pulmonary arterial pressure 43 ± 2 mmHg, PVR 600 ± 43 dyn ∗ s ∗ cm(-5), 56.4% treatment-naïve) were included. Mean right ventricular (RV) area significantly decreased after 3 (-2.1 ± 3.9 cm(2), equals -7.4 ± 15.3%, p = 0.002), 6 (-4.2 ± 3.2 cm(2), equals -16.1 ± 11.5%, p < 0.001) and 12 months (-5.9 ± 4.6 cm(2), equals -22.1 ± 14.2%, p < 0.001) compared to baseline. Right atrial area significantly decreased after 12 months (-3.5 ± 4.1cm(2), equals -16.8 ± 19.2%, p < 0.001) and TAPSE significantly improved after 6 (+ 2 ± 4.7, equals 12 ± 25.8%, p = 0.025) and 12 months (+ 3.6 ± 5.4, equals 21.0 ± 29.6%, p = 0.002). Furthermore, RV wall thickness and 6MWD significantly improved after 3, 6 and 12 months (p < 0.05). Invasive hemodynamics significantly improved after 3 months. Both LOCF and BOCF showed similar significance and lower effect sizes.

CONCLUSION

Long-term treatment with riociguat significantly reduced right heart size and improved RV function in PAH and CTEPH. Further prospective studies are needed to confirm these results.

Right Heart Score for Predicting Outcome in Idiopathic, Familial, or Drug- and Toxin-Associated Pulmonary Arterial Hypertension

OBJECTIVES

This study sought to determine whether a simple score combining indexes of right ventricular (RV) function and right atrial (RA) size would offer good discrimination of outcome in patients with pulmonary arterial hypertension (PAH).

BACKGROUND

Identifying a simple score of outcome could simplify risk stratification of patients with PAH and potentially lead to improved tailored monitoring or therapy.

METHODS

We recruited patients from both Stanford University (derivation cohort) and VU University Medical Center (validation cohort). The composite endpoint for the study was death or lung transplantation. A Cox proportional hazard with bootstrap CI adjustment model was used to determine independent correlates of death or transplantation. A predictive score was developed using the beta coefficients of the multivariable models.

RESULTS

For the derivation cohort (n = 95), the majority of patients were female (79%), average age was 43 ± 11 years, mean pulmonary arterial pressure was 54 ± 14 mm Hg, and pulmonary vascular resistance index was 25 ± 12 Wood units × m(2). Over an average follow-up of 5 years, the composite endpoint occurred in 34 patients, including 26 deaths and 8 patients requiring lung transplant. On multivariable analysis, RV systolic dysfunction grade (hazard ratio [HR]: 3.4 per grade; 95% confidence interval [CI]: 2.0 to 7.8; p < 0.001), severe RA enlargement (HR: 3.0; 95% CI: 1.3 to 8.1; p = 0.009), and systemic blood pressure <110 mm Hg (HR: 3.3; 95% CI: 1.5 to 9.4; p < 0.001) were independently associated with outcome. A right heart (RH) score constructed on the basis of these 3 parameters compared favorably with the National Institutes of Health survival equation (0.88; 95% CI: 0.79 to 0.94 vs. 0.60; 95% CI: 0.49 to 0.71; p < 0.001) but was not statistically different than the REVEAL (Registry to Evaluate Early and Long-Term PAH Disease Management) score c-statistic of 0.80 (95% CI: 0.69 to 0.88) with p = 0.097. In the validation cohort (n = 87), the RH score remained the strongest independent correlate of outcome.

CONCLUSIONS

In patients with prevalent PAH, a simple RH score may offer good discrimination of long-term outcome.

Pulmonary Hypertension in the Intensive Care Unit

Pulmonary hypertension occurs as the result of disease processes increasing pressure within the pulmonary circulation, eventually leading to right ventricular failure. Patients may become critically ill from complications of pulmonary hypertension and right ventricular failure or may develop pulmonary hypertension as the result of critical illness. Diagnostic testing should evaluate for common causes such as left heart failure, hypoxemic lung disease and pulmonary embolism. Relatively few patients with pulmonary hypertension encountered in clinical practice require specific pharmacologic treatment of pulmonary hypertension targeting the pulmonary vasculature. Management of right ventricular failure involves optimization of preload, maintenance of systemic blood pressure and augmentation of inotropy to restore systemic perfusion. Selected patients may require pharmacologic therapy to reduce right ventricular afterload by directly targeting the pulmonary vasculature, but only after excluding elevated left heart filling pressures and confirming increased pulmonary vascular resistance. Critically-ill patients with pulmonary hypertension remain at high risk of adverse outcomes, requiring a diligent and thoughtful approach to diagnosis and treatment.

Biomechanics of the right ventricle in health and disease (2013 Grover Conference series)

Right ventricular (RV) function is a major determinant of the symptomatology and outcome in pulmonary hypertension. The normal RV is a thin-walled flow generator able to accommodate large changes in venous return but unable to maintain flow output in the presence of a brisk increase in pulmonary artery pressure. The RV chronically exposed to pulmonary hypertension undergoes hypertrophic changes and an increase in contractility, allowing for preserved flow output in response to peripheral demand. Failure of systolic function adaptation (homeometric adaptation, described by Anrep's law of the heart) results in increased dimensions (heterometric adaptation; Starling's law of the heart), with a negative effect on diastolic ventricular interactions, limitation of exercise capacity, and vascular congestion. Ventricular function is described by pressure-volume relationships. The gold standard of systolic function is maximum elastance (E max), or the maximal value of the ratio of pressure to volume. This value is not immediately sensitive to changes in loading conditions. The gold standard of afterload is arterial elastance (E a), defined by the ratio of pressure at E max to stroke volume. The optimal coupling of ventricular function to the arterial circulation occurs at an E max/E a ratio between 1.5 and 2. Patients with severe pulmonary hypertension present with an increased E max, a trend toward decreased E max/E a, and increased RV dimensions, along with progression of the pulmonary vascular disease, systemic factors, and left ventricular function. The molecular mechanisms of RV systolic failure are currently being investigated. It is important to refer biological findings to sound measurements of function. Surrogates for E max and E a are being developed through bedside imaging techniques.

Impact of lowering pulmonary vascular resistance on right and left ventricular deformation in pulmonary arterial hypertension

AIMS

As pulmonary arterial hypertension (PAH) is associated with significant morbidity and mortality, particularly among patients with right ventricular (RV) dysfunction, we aimed to determine the impact of therapy to reduce pulmonary vascular resistance (PVR) on RV and LV deformation in PAH.

METHODS AND RESULTS

Right ventricular free wall longitudinal strain (FWLS) and LV global circumferential strain (CS) were measured at baseline, 12 weeks, and 24 weeks in 68 patients with advanced PAH randomized to imatinib or placebo in the Imatinib in Pulmonary arterial hypertension, a Randomized Efficacy Study (IMPRES) trial, and compared with 30 healthy controls. Compared with controls, PAH was associated with impaired RV FWLS (-15.9 ± 5.4 vs. -30.8 ± 4.3, respectively; P < 0.0001) and LV septal CS (-24.2 ± 8.2 vs. -31.4 ± 5.3, respectively, P < 0.0001), but not LV global CS. Improvement in PVR and mean pulmonary artery pressure (MPAP) over a 24-week period was significantly associated with improvement in RV FWLS (r = 0.39, P = 0.02; 0.33, P = 0.04 respectively), LV global CS (r = 0.61, P = 0.0001; r = 0.60, P = 0.0001, respectively), and LV septal CS (r = 0.50, P = 0.005; r = 0.56, P = 0.002, respectively). These associations were most robust with LV global and septal CS. Imatinib therapy was associated with improvement in RV FWLS compared with placebo.

CONCLUSIONS

PAH is associated with impaired biventricular deformation. Reduction in PVR is associated with improvements in both RV and LV deformation, coupled to improvements in MPAP and stroke volume index, with LV global and septal CS the strongest correlates of these changes. RV FWLS is sensitive to treatment effect, demonstrating greater improvement with imatinib compared with placebo.

TRIAL REGISTRATION

NCT00902174.