Echocardiography in pulmonary arterial hypertension

Echocardiography and pulmonary hypertension in patients with chronic obstructive pulmonary disease undergoing lung transplantation evaluation

BACKGROUND

The use of echocardiography in pulmonary hypertension (PH) in advanced chronic obstructive pulmonary disease (COPD) is understudied. We aimed to compare the performance of echocardiography with right heart catheterization (RHC) in the diagnosis of PH in COPD patients undergoing lung transplant evaluation.

METHODS

We included 111 patients with severe COPD who underwent RHC in a single center as part of lung transplantation evaluation. COPD-PH and severe COPD-PH were defined based on RHC per the 6th world symposium on pulmonary hypertension. Echocardiographic probability of PH was described according to the European Society of Cardiology guidelines. Summary and univariate analyses were performed.

RESULTS

The mean age (±SD) was 62 (8) and 47% (n=52) were men. A total of 82 patients (74 %) had COPD-PH. The sensitivity, specificity, positive predictive, and negative predictive values of echocardiography in diagnosing COPD-PH were 43 %, 83 %, 88 %, and 34 % respectively and for severe COPD-PH were 67 %, 75 %, 50 %, and 86 % respectively. Echocardiography was consistent with RHC in ruling in/out PH in 53% (n=59) of patients. After controlling for age, sex. BMI, pack year, echocardiography-RHC time difference, GOLD class, FVC, and CT finding of emphysema, higher TLC decreased consistency (parameter estimate=-0.031; odds ratio: 0.97, 95%CI 0.94-0.99; p=0.037) and higher DLCO increased consistency (parameter estimate=0.070; odds ratio: 1.07, 95%CI 0.94-0.99; p=0.026).

CONCLUSIONS

Echocardiography has high specificity but low sensitivity for the diagnosis of PH in advanced COPD. Its performance improves when ruling out severe COPD-PH. This performance correlates inversely with lung hyperinflation.

Characteristics and prognostic significance of right heart remodeling and tricuspid regurgitation after pulmonary endarterectomy

OBJECTIVE

Right heart remodeling and tricuspid regurgitation (TR) are common in patients with chronic thromboembolic pulmonary hypertension. This study aimed to investigate the significance of right heart remodeling and TR after pulmonary endarterectomy (PEA) in patients with chronic thromboembolic pulmonary hypertension.

METHODS

Patients who underwent PEA with preoperative and postoperative transthoracic echocardiograms at our center between June 2010 and July 2019 were retrospectively reviewed. The composite end point was defined as death or hospitalization due to worsening heart failure, bleeding, or recurrent pulmonary embolism.

RESULTS

In total, 158 patients were included for analysis. Right ventricular basal (48 [45-52] vs 43 [39-47] mm, P < .001), midcavitary (46 [42-50] vs 38 [34-42] mm, P < .001), and longitudinal dimensions (87 [83-93] vs 80 [75-84] mm, P < .001), along with the right atrial volume index (37 [25-51] vs 24 [18-34] mL/m2, P < .001), significantly decreased, whereas left ventricular and atrial sizes and left ventricular ejection fraction increased after PEA. Overall, 78 patients (49%) showed significant TR on preoperative transthoracic echocardiograms, and 33 (21%) had significant residual TR after PEA. Fourteen patients died, and 24 patients met the composite end point. Residual TR after PEA was independently associated with mortality (P = .005) and the composite end point (P = .003). Patients with residual TR had significantly worse survival (log-rank P < .001) and greater event rates (log-rank P = .003) than those without residual TR.

CONCLUSIONS

Significant improvements in right heart remodeling were seen following PEA. However, residual TR was a poor prognostic marker.

Apply pressure-strain loop to quantify myocardial work in pulmonary hypertension: A prospective cohort study

Objectives

Pressure-strain loop (PSL) is a novel method to quantify myocardial work in many cardiovascular diseases. To investigate the value of myocardial work parameters derived from PSL for evaluating cardiac function and clinical prognosis in patients with pulmonary hypertension (PH).

Methods

A total of 52 patients with PH and 27 healthy controls were enrolled in this prospective study. PSLs determined by echocardiography were used to calculate global work index (GWI) of left ventricle (LV) and right ventricle (RV). Global constructive work (GCW) comprised the sum of myocardial work performed during shortening in systole and during lengthening in isovolumic relaxation. Global wasted work (GWW) comprised the sum of myocardial work performed during lengthening in systole and during shortening in isovolumic relaxation. Global work efficiency (GWE) was defined as GCW/(GCW + GWW).

Results

LVGWW, RVGWI, RVGCW and RVGWW were significantly higher in patients than controls (all P < 0.001). LVGWE, LVGWI, LVGCW, and RVGWE were lower in patients than controls (all P < 0.01). Myocardial work parameters correlated well with clinical and other conventional echocardiographic assessments (all P < 0.05). In binary logistic regression analysis, the combination of RVGWE and estimation of pulmonary arterial systolic pressure (ePASP) was the best model to predict clinical outcomes (OR = 0.803, P = 0.002 and OR = 1.052, P = 0.015, respectively). Receiver operating characteristic curv demonstrated the combination of RVGWE and ePASP was the best predictor of adverse events with 100% sensitivity and 76.3% specificity (AUC = 0.910, P < 0.001).

Conclusion

Myocardial work parameters derived from PSL are emerging markers of cardiac function. And the combination of RVGWE and ePASP is a useful predictor of clinical outcome in PH patients.

Echocardiography in Pulmonary Arterial Hypertension: Comprehensive Evaluation and Technical Considerations

Pulmonary arterial hypertension (PAH) is a rare, progressive disease in which there is a persistent, abnormal increase in pulmonary artery pressure. Symptoms of pulmonary hypertension are nonspecific and mainly associated with progressive right ventricular failure. The diagnosis of PAH is a multistep process and often requires the skillful use of several tests. The gold standard for the diagnosis of PAH is hemodynamic testing. Echocardiography currently plays an important role in the diagnostic algorithm of PAH as it is minimally invasive and readily available. Moreover, many echocardiographic parameters are closely related to pulmonary hemodynamics. It allows assessment of the right heart′s structure and function, estimation of the pressure in the right ventricle, right atrium, and pulmonary trunk, and exclusion of other causes of elevated pulmonary bed pressure. Echocardiographic techniques are constantly evolving, and recently, measurements made using new techniques, especially 3D visualization, have become increasingly important. In echocardiographic assessment, it is crucial to know current guidelines and new reports that organize the methodology and allow standardization of the examination. This review aims to discuss the different echocardiographic techniques used to evaluate patients with PAH.

Risk Factors and Outcomes of Pulmonary Hypertension in Infants With Bronchopulmonary Dysplasia: A Meta-Analysis

Background: Pulmonary hypertension is one of the most common co-morbidities in infants with bronchopulmonary dysplasia (BPD), but its risk factors are unclear. The onset of pulmonary hypertension in BPD has been associated with poor morbidity- and mortality-related outcomes in infants. Two review and meta-analysis studies have evaluated the risk factors and outcomes associated with pulmonary hypertension in infants with BPD. However, the limitations in those studies and the publication of recent cohort studies warrant our up-to-date study. We designed a systematic review and meta-analysis to evaluate the risk factors and outcomes of pulmonary hypertension in infants with BPD. Objective: To systematically evaluate the risk factors and outcomes associated with pulmonary hypertension in infants with BPD. Methods: We systematically searched the academic literature according to the PRISMA guidelines across five databases (Web of Science, EMBASE, CENTRAL, Scopus, and MEDLINE). We conducted random-effects meta-analyses to evaluate the pulmonary hypertension risk factors in infants with BPD. We also evaluated the overall morbidity- and mortality-related outcomes in infants with BPD and pulmonary hypertension. Results: We found 15 eligible studies (from the initial 963 of the search result) representing data from 2,156 infants with BPD (mean age, 25.8 ± 0.71 weeks). The overall methodological quality of the included studies was high. Our meta-analysis in infants with severe BPD revealed increased risks of pulmonary hypertension [Odds ratio (OR) 11.2], sepsis (OR, 2.05), pre-eclampsia (OR, 1.62), and oligohydramnios (OR, 1.38) of being small for gestational age (3.31). Moreover, a comparative analysis found medium-to-large effects of pulmonary hypertension on the total duration of hospital stay (Hedge's g, 0.50), the total duration of oxygen received (g, 0.93), the cognitive score (g, -1.5), and the overall mortality (g, 0.83) in infants with BPD. Conclusion: We identified several possible risk factors (i.e., severe BPD, sepsis, small for gestational age, pre-eclampsia) which promoted the onset of pulmonary hypertension in infants with BPD. Moreover, our review sheds light on the morbidity- and mortality-related outcomes associated with pulmonary hypertension in these infants. Our present findings are in line with the existing literature. The findings from this research will be useful in development of efficient risk-based screening system that determine the outcomes associated with pulmonary hypertension in infants with BPD.

Pulmonary Hypertension in Heart Failure Patients

The development of pulmonary hypertension (PH) in patients with heart failure is associated with increased morbidity and mortality. In this article, the authors examine recent changes to the definition of PH in the setting of left heart disease (PH-LHD), and discuss its epidemiology, pathophysiology and prognosis. They also explore the complexities of diagnosing PH-LHD and the current evidence for the use of medical therapies, promising clinical trials and the role of left ventricular assist device and transplantation.

Pulmonary hypertension subjects exhibit right ventricular transient exertional dilation during supine exercise stress echocardiography

Pulmonary hypertension is a condition with high morbidity and mortality. Resting transthoracic echocardiography is a pivotal diagnostic and screening test for pulmonary hypertension. The role of exercise stress echocardiography in the diagnosis of pulmonary hypertension is not well-established. We studied right ventricular size changes during exercise using exercise stress echocardiography to assess differences between normal and pulmonary hypertension patients and evaluate test safety, feasibility, and reproducibility. Healthy control and pulmonary hypertension patients performed recumbent exercise using a bicycle ergometer. Experienced echocardiography sonographers recorded the following resting and peak exercise right ventricular parameters using the apical four chamber view: end-diastolic area; end-systolic area; mid-diameter; basal diameter; and longitudinal diameter. Two cardiologists masked to clinical information subsequently analyzed the recordings. Parameters with acceptable inter-rater reliability were analyzed for statistical differences between the normal and pulmonary hypertension patient groups and their association with pulmonary hypertension. We enrolled 38 healthy controls and 40 pulmonary hypertension patients. Exercise stress echocardiography testing was found to be safe and feasible. Right ventricular size parameters were all readily obtainable and all had acceptable inter-observer reliability except for right ventricular longitudinal diameter. During exercise, healthy controls demonstrated a decrease in right ventricular end-systolic area, end-diastolic area, mid-diameter, and basal diameter (P < 0.05). Conversely, pulmonary hypertension patients demonstrated an increase in right ventricular end-systolic area, end-diastolic area, and mid-diameter (P < 0.05). These changes were unaffected by multivariate corrections. The sensitivity for pulmonary hypertension of an increase in right ventricular size was 97.2% with a negative predictive value of 95.2%. The ROC C-statistic for increase in right ventricular size was 0.93. This transient exertional dilation (TED) of the right ventricle is observed in pulmonary hypertension patients but not in healthy controls. Recumbent right ventricular exercise stress echocardiography is a feasible and safe diagnostic test for pulmonary hypertension which warrants additional study.

Prospective study of pulmonary hypertension in preterm infants with bronchopulmonary dysplasia

OBJECTIVE

To evaluate the prevalence, risk factors, and optimal timing of echocardiogram for pulmonary hypertension (PH) in infants with bronchopulmonary dysplasia (BPD).

DESIGN

In this prospective study, infants with gestational age (GA) <30 weeks admitted to a tertiary NICU between July 2015 and June 2017 who required positive pressure ventilation or oxygen therapy at ≥28 days of life were evaluated with serial echocardiograms at study enrollment (4-6 weeks of age), 32 weeks (only for ≤25 weeks), 36, and 40 weeks post-menstrual age (PMA) for PH.

RESULTS

Of 126 infants (mean birth weight 858 ± 221 g; mean GA 26.1 ± 1.6 wks), 48 (38%) developed PH at any time during their hospital stay. The first study echocardiogram was performed at a median age of 31 weeks PMA. The prevalence of PH was 36/126 (28.5%) at enrollment, at 6/30 (20%) at 32 weeks, 24/111 (21.6%) at 36 weeks, and 10/59 (17%) at 40 weeks. No new cases of PH were identified at 40 weeks. At 36 weeks, none of the infants with mild BPD had PH, whereas 20% of moderate and 32% of severe BPD infants had PH. After controlling for confounding variables severe BPD (OR 3.31, 95%CI 1.12, 9.74), and ventilator associated pneumonia (VAP) (OR 17.9, 95%CI 3.9, 82.11) remained independent risk factors for BPD-associated PH.

CONCLUSION

Echocardiographic screening for PH can be safely restricted to infants with moderate or severe BPD at 36 weeks PMA. We identified VAP as an independent risk factor for PH.

Early Diagnostic Features of Left-to-Right Shunt-Induced Pulmonary Arterial Hypertension in Piglets

BACKGROUND

We aimed to establish early diagnostic characteristics of left-to-right shunt-induced pulmonary arterial hypertension (PAH) in a piglet model.

METHODS

A shunt-induced PAH in piglets (n = 9) was successfully established by anastomosis of vascular prosthesis from aorta to pulmonary artery with follow-up for 6 months by a number of diagnostic procedures.

RESULTS

PAH developed with mean pulmonary arterial pressure [PAP] of 30.2 ± 6.0 mm Hg immediately after operation and 33.5 ± 8.7 mm Hg at 3 months after operation with pulmonary vascular resistance increased to 4.0 ± 0.9 Wood units. There was a weak correlation on systolic PAP between catheterization and echocardiography but the Tei index was significantly correlated to systolic PAP. Magnetic resonance imaging demonstrated that the end-diastolic volume index, systolic volume index, ejection fraction of the ventricle, and ventricular mass index were sensitive indices. Technetium-99m single-photon emission computed tomography indicated increased blood flow in the upper and middle zones of both lungs. Positron emission tomography-computed tomography (PET-CT) demonstrated a higher kilo count (kct) of ¹⁸F-fluorodeoxyglucose in the right ventricular wall and both chambers at 3 months postoperatively (right ventricular wall: 5,708.3 ± 428.4 versus 3,965.5 ± 138.6 preoperatively, p = 0.003; both chambers: 2,963.6 ± 219.4 versus 1,710.1 ± 35.4 preoperatively, p < 0.05) as well as at 6 months for both chambers (p < 0.05).

CONCLUSIONS

In this successful left-to-right shunt-induced PAH model in piglets, sensitive indices including the Tei index, systolic volume index, ejection fraction, ventricular mass index, lung perfusion, and glycometabolism by PET-CT in early PAH are determined. For the first time, we report that glycometabolism by PET-CT is useful in early diagnosis. These indices may be used for the early diagnosis in the left-to-right shunt-induced PAH.

Elevated Mean Pulmonary Artery Pressure and Right Ventricular Dysfunction in Children with Chronic Kidney Disease

Background

Elevated mean pulmonary artery pressure (mPAP) and right heart failure increase mortality in patients with chronic kidney disease (CKD).

Objectives

The objective of this study is to determine the prevalence of elevated mPAP in children with CKD compared with matched controls and to ascertain the relationship between elevated mPAP with right ventricular dysfunction and history of hemodialysis.

Materials and Methods

A cross-sectional comparative study of mPAP and tricuspid annular plane systolic excursion of 21 children with CKD and age- and sex-matched controls asymptomatic for cardiac disease was conducted.

Results

Median mPAP was 27.69 (18.3-36.1) mmHg in CKD patients compared with 14.55 (13.5-17.1) mmHg in controls (P = 0.002). Elevated mPAP was present in 42.9% of CKD group and 0% in controls (P < 0.001). The prevalence of right ventricle (RV) dysfunction in CKD was 9.5% and 0% in controls (P = 0.49). Right ventricular dysfunction was significantly more common in patients with elevated mPAP compared with those with normal mPAP (P < 0.001). Children with CKD who had a history of having been dialyzed were less likely to have elevated mPAP (P < 0.001).

Conclusion

Elevated mPAP is significantly more common in children with CKD compared with controls. CKD population with mPAP elevation is more likely to have impaired RV function. The occurrence of elevated mPAP was more common in those who were never dialyzed.

Team-based approach to identify cardiac toxicity in critically ill hematopoietic stem cell transplant recipients

INTRODUCTION

We observed pulmonary hypertension (PH), pericardial effusions, and left ventricular systolic dysfunction (LVSD) in multiple critically ill hematopoietic stem cell transplant (HSCT) recipients. We implemented routine structured echocardiography screening for HSCT recipients admitted to the pediatric intensive care unit (PICU) using a standardized multidisciplinary process.

METHODS

HSCT recipients admitted to the PICU with respiratory distress, hypoxia, shock, and complications related to transplant-associated thrombotic microangiopathy were screened on admission and every 1-2 weeks thereafter. Echocardiography findings requiring intervention and/or further screening included elevated right ventricular pressure, LVSD, and moderate to large pericardial effusions. All echocardiograms were compared to the patient's routine pretransplant echocardiogram.

RESULTS

Seventy HSCT recipients required echocardiography screening over a 3-year period. Echo abnormalities requiring intervention and/or further screening were found in 35 (50%) patients. Twenty-four (34%) patients were noted to have elevated right ventricular pressure; 14 (20%) were at risk for PH, while 10 (14%) had PH. All patients with PH were treated with pulmonary vasodilators. LVSD was noted in 22 (31%) patients; 15/22 (68%) received inotropic support. Moderate to large pericardial effusions were present in nine (13%) patients, with six needing pericardial drain placement.

DISCUSSION

Echocardiographic abnormalities are common in critically ill HSCT recipients. Utilization of echocardiogram screening may allow for early detection and timely intervention for cardiac complications in this high-risk cohort.

Differences in right ventricular morphology, not function, indicate the nature of increased afterload in pulmonary hypertensive subjects with normal left ventricular function

BACKGROUND

The aim of study was to assess whether a specific morphology of the right ventricle (RV) by 2D echo predicts the hemodynamic nature of pulmonary hypertension (PH).

METHODS

We reviewed clinical, 2D echo, and hemodynamic data of 100 patients with PH: divided into three groups: PH from pulmonary vascular disease (PH_PVD ; n = 34) with pulmonary vascular resistance (PVR) > 3 mm Hg/L/min (Wood unit [WU]) and pulmonary artery wedge pressure (PAWP) ≤ 15 mm Hg, pulmonary venous hypertension (PVH; n = 33) with PVR < 3 WU and PAWP > 15 mm Hg and PH_MIXED (n = 33) with PVR > 3 WU and PAWP > 15 mm Hg. We analyzed several two-dimensional parameters of right heart morphology and function, including the degree of tapering of the RV diameter from base (just above tricuspid annulus) to apex (level of moderator band) in the apical four-chamber view. P = <.05.

RESULTS

Baseline characteristics were similar in all three groups: age 62 ± 14.4 years, 69% females, 57% Caucasians. Hemodynamics and 2D echo data of PH_PVD vs PVH vs PH_MIXED were as follows: PVR 13 ± 6 vs 2 ± 1 vs 7 ± 2 WU, mean pulmonary artery pressure 53 ± 14 vs 34 ± 8 vs 49 ± 8 mm Hg and cardiac index 2.0 ± 0.5 vs 2.8 ± 0.7 vs 2.2 ± 0.7 L/m² , RV base/apex ratio during systole (sRV_b/a ) 1.3 ± 0.2 vs 2.6 ± 0.5 vs 1.5 ± 0.3. Thus, sRV_b/a was twofold higher in the PVH vs PH_PVD cohort. On ROC analysis, the AUC for sRV_b/a for predicting PVR > 3 WU was 0.873, with optimal cutoff of 1.5.

CONCLUSION

Systolic RV base/apex ratio is a simple 2D index of RV shape that powerfully predicts a PVR > 3 WU and provides powerful discriminating ability between PVH and PH_PVD .

Evaluation of two-dimensional strain echocardiography for quantifying right ventricular function in patients with pulmonary arterial hypertension

The aim of the current study was to evaluate the use of two-dimensional strain echocardiography (2DS) in quantifying right ventricular (RV) function in patients with pulmonary arterial hypertension (PAH). A total of 41 patients with PAH and 40 healthy control patients were recruited to the study. 2DS was used to determine the strain (ε) and strain rate (SR) of basal, middle and apical segments of the RV free wall. The aforementioned indicators were compared with measurements of RV function taken by conventional ultrasound and right heart catheterization. The ε and SR of all segments of the right ventricular free wall were significantly lower in the PAH group, as compared with the control group (P<0.05). In the PAH group, the ε and SR of the middle and apical segments were significantly lower compared with basal segments (P<0.01). The SR of the apical segments were positively correlated with the area and diameter of the right ventricular. The ε of the apical segments were positively correlated with RV area, diameter and systolic function. The ε and SR of apical segments were positively correlated with pulmonary artery pressure and pulmonary vascular resistance measured by right heart catheterization. These findings indicated that 2DS can accurately evaluate RV longitudinal systolic function.

Transthoracic Echocardiography and Chest Computed Tomography Arteriography in Patients with Acute Pulmonary Embolism: A Two-Year Follow-Up Study

BACKGROUND

Pulmonary hypertension (PH) is frequently found at the time of diagnosis of pulmonary embolism (PE). An incomplete resolution of PE can lead to chronic thromboembolic pulmonary hypertension (CTPH). Transthoracic echocardiogram (TTE) is the first step to diagnose an abnormality of the pulmonary vasculature. Based on computed tomography (CT), the Qanadli vascular obstruction index has been extensively used to assess acute PE.

OBJECTIVES

Our aim was to ascertain whether at the time of diagnosis of an acute PE episode TTE variables and a Qanadli CT index score may be associated with CTPH 2 years later.

METHOD

Patients with PE were prospectively enrolled. TTE was performed and the Qanadli CT obstruction index was calculated on admission to the hospital, while only TTE was repeated at the 2-year follow-up. The NYHA (New York Heart Association) functional classification was evaluated. Correlation analyses were performed.

RESULTS

Twenty patients (11 males, median age 69.5 years) were considered for the study. There was no significant correlation between TTE parameters and the Qanadli CT obstruction index. A significant distribution (χ2 = 5.69, p = 0.017) was found in the analysis among patients with CTPH at 24 months and the Qanadli CT index, categorized by a receiver operating characteristic curve cutoff value of 42.5%. Additionally, a significant distribution (χ2 = 4.09, p = 0.043) was found in the analysis among patients with CTPH at 24 months and right ventricular systolic pressure on admission, categorized as PH (>31 mm Hg).

CONCLUSION

Our study demonstrates that in patients with acute PE there is no relationship between the Qanadli CT obstruction index and TTE parameters on admission to the hospital. However, the occurrence of CTPH at the 24-month follow-up is associated with PH and with a high Qanadli CT obstruction index score.

[Pulmonary hypertension in hemodialysis patients: Prevalence and associated factors]

BACKGROUND AND OBJECTIVE

Pulmonary hypertension (PH) is a progressive disorder that can be caused by several underlying conditions or an intrinsic alteration of the pulmonary vasculature. Chronic increased pressure in the pulmonary vasculature leads to changes in the architecture of the vessels that can perpetuate PH and produce right ventricular dysfunction. These structural and functional alterations can decrease survival and quality of life of patients on hemodialysis; however, there is a lack of evidence about this problem in this population. The aim of this study is to establish the prevalence of PH in patients on hemodialysis and its association with specific factors related to this patient population.

MATERIAL AND METHODS

We included 202 prevalent patients on hemodialysis for at least 6 months and who were clinically stable. We collected demographic data, routine laboratory parameters and data of 2D Doppler-echocardiography. PH was defined as a systolic pulmonary artery pressure (SPAP) estimated by Doppler ultrasound above 35mmHg. Hydration status was assessed by determining the plasma concentration of N-terminal pro brain natriuretic peptide (Nt-proBNP).

RESULTS

PH prevalence was 37.1% (75 patients). The average SPAP in the entire study population was 32±12mmHg and in the group with PH it was 45±11mmHg. We found a direct and statistically significant correlation between the presence of PH and age (P=.001), time on renal replacement therapy (P=.04), the presence of systolic dysfunction (P=.007), diastolic dysfunction (P= 01), mitral valve disease (P=.01) and double mitral and aortic disease (P=.007). Volume overload was closely associated with PH, as demonstrated by the correlation between the SPAP and Nt-proBNP levels (P=.001).

CONCLUSION

We conclude that prevalence of PH in hemodialysis patients is high. And one of the most important associated factors is volume overload. More studies are needed to establish the impact of PH on morbidity and mortality of patients and to assess whether a better volume control improves PH.

Chronic Pulmonary Complications of Sickle Cell Disease

Sickle cell disease (SCD), the most common genetic hemolytic anemia worldwide, affects 250,000 births annually. In the United States, SCD affects approximately 100,000 individuals, most of African descent. Hemoglobin S (HbS) results from a glutamate-to-valine mutation of the sixth codon of the β-hemoglobin allele; the homozygous genotype (HbSS) is associated with the most prevalent and severe form of the disease. Other SCD genotypes include HbSC, composed of one HbS allele and one HbC (glutamate-to-lysine mutation) allele; and HbS-β-thalassemia(0) or HbS-β-thalassemia(+), composed of one HbS allele and one β-thalassemia allele with absent or reduced β-chain production, respectively. Despite advances in care, median survival remains in the fifth decade, due in large part to chronic complications of the disease. Chronic pulmonary complications in SCD are major contributors to this early mortality. Although our understanding of these conditions has improved much over the past 10 to 15 years, there remains no specific treatment for pulmonary complications of SCD. It is unclear whether conventional treatment regimens directed at non-SCD populations have equivalent efficacy in patients with SCD. This represents a critical research need. In this review, the authors review the state-of-the-art understanding of the following pulmonary complications of SCD: (1) pulmonary hypertension; (2) venous thromboembolic disease; (3) sleep-disordered breathing; (4) asthma and recurrent wheezing; and (5) pulmonary function abnormalities. This review highlights the advances as well as the knowledge gaps in this field to update clinicians and other health care providers and to garner research interest from the medical community.

A Practical Clinical Approach to the Diagnosis and Treatment of Patients with Pulmonary Hypertension

Pulmonary hypertension is defined by a mean pulmonary artery pressure of >25 mmHg at rest or 30 mmHg during exercise. There are many causes and currently diseases causing the condition are classified into five groups. The greatest elevation in pulmonary arterial pressure is found among those disorders in group 1 (known as pulmonary arterial hypertension [PAH]) and research and targeted therapy has focused on this group in particular, although patients in group 4 (chronic thromboembolic PH [CTEPH]) also receive advanced pulmonary vasodilator therapy. The symptoms of PH are often vague and the diagnosis is frequently missed or delayed. Efforts are therefore being made to improve awareness of PH among clinicians to enable prompt referral to a PH unit to confirm the diagnosis and instigate appropriate therapy. Multi-disciplinary team (MDT) discussion is necessary if patients with PH require surgical intervention or become pregnant. For patients in the other PH groups, treatment is usually concentrated on the primary disorder. A small number of patients with PAH will respond to calcium-channel-blocking agents. Specific targeted therapy is often given in combination depending on the patients functional performance status. Available agents include phosphodiesterase type V inhibitors, endothelin receptor antagonists, prostglandin analogues and nitric oxide. Many novel agents are under review. For carefully selected patients surgical options, include lung transplantation, pulmonary thromboendarterectomy and atrial septostomy.

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.

Use of outcome measures in pulmonary hypertension clinical trials

OBJECTIVES

To evaluate the use of surrogate measures in pulmonary hypertension (PH) clinical trials and how it relates to clinical practice.

BACKGROUND

Studies of pulmonary arterial hypertension (PAH) employ a variety of surrogate measures in addition to clinical events because of a small patient population, participant burden, and costs. The use of these measures in PH drug trials is poorly defined.

METHODS

We searched PubMed/MEDLINE/Embase for randomized or prospective cohort PAH clinical treatment trials from 1985 to 2013. Extracted data included intervention, trial duration, study design, patient characteristics, and primary and secondary outcome measures. To compare with clinical practice, we assessed the use of surrogate measures in a clinical sample of patients on PH medications at Duke University Medical Center between 2003 and 2014.

RESULTS

Between 1985 and 2013, 126 PAH trials were identified and analyzed. Surrogate measures served as primary endpoints in 119 trials (94.0%). Inclusion of invasive hemodynamics decreased over time (78.6%, 75.0%, 52.2%; P for trend = .02), while functional testing (7.1%, 60.0%, 81.5%; P for trend < .0001) and functional status or quality of life (0%, 47.6%, 62.8%; P for trend < .0001) increased in PAH trials over the same time periods. Echocardiography data were reported as a primary or secondary outcome in 32 trials (25.4%) with increased use from 1985-1994 to 1995-2004 (7.1% vs 35.0%, P = .04), but the trend did not continue to 2005-2013 (25.0%). In comparison, among 450 patients on PAH therapies at our institution between 2003 and 2013, clinical assessments regularly incorporated serial echocardiography and 6-minute walk distance tests (92% and 95% of patients, respectively) and repeat measurement of invasive hemodynamics (46% of patients).

CONCLUSIONS

The majority of PAH trials have utilized surrogate measures as primary endpoints. The use of these surrogate endpoints has evolved significantly over time with increasing use of patient-centered endpoints and decreasing or stable use of imaging and invasive measures. In contrast, imaging and invasive measures are commonly used in contemporary clinical practice. Further research is needed to validate and standardize currently used measures.

Pulmonary hypertension: types and treatments

Pulmonary arterial hypertension (PAH) is a panvasculopathy that affects the distal pulmonary arteries and leads to restricted blood flow. This increased afterload leads to adaptive mechanisms of the right ventricle, with eventual failure once it can no longer compensate. Pulmonary hypertension from associated conditions, most importantly left heart disease, i.e. heart failure, can also lead to the same sequela. Patients often experience early vague symptoms of dyspnea and exercise intolerance, and thus PH can elude clinicians until right heart failure symptoms predominate. Evidence-based treatment options with pulmo-nary vasodilators are available for those with PAH and should be employed early. It is essential that patients be accurately categorized by their etiology of PH, as treatment strategies differ, and can potentially be dangerous if employed in the wrong clinical scenario.

Right ventricular echocardiographic indices predict poor outcomes in infants with persistent pulmonary hypertension of the newborn

AIMS

Infants with persistent pulmonary hypertension of the newborn (PPHN) have elevated pulmonary vascular resistance that can lead to right ventricular (RV) failure and death. Clinicians must decide which infants will fail conventional therapy and require transfer to extra corporeal membrane oxygenation (ECMO) centres, but accurate echocardiographic predictors have not been identified. We assessed echocardiographic measurements of RV pressure and function in predicting progression to death or ECMO in infants with PPHN.

METHODS AND RESULTS

Echocardiograms for infants ≥35-week gestation with a clinical diagnosis of PPHN were retrospectively reviewed. Traditional and strain echocardiographic measures were compared for those with or without the primary outcome of ECMO/cardiovascular death. Receiver operator curves identified cut points for measures that were significantly different. Of the 86 subjects analysed, 25 (29%) of the patients had the primary outcome of ECMO/death. The ECMO/death group had diminished tricuspid annular plane systolic excursion (TAPSE; P = 0.002) and RV global longitudinal peak strain (GLPS; P = 0.03), a predominant right-to-left shunt across the patent ductus arteriosus (PDA; P = 0.05), and an elevated oxygenation index (OI; P < 0.001). Sensitivity/specificity for TAPSE <4 mm was 56 and 85%, and for GLPS greater than or equal to -9% was 52 and 77%.

CONCLUSION

TAPSE, GLPS, and right-to-left PDA shunting were associated with progression to death/ECMO. RV free wall strain was not associated with the outcome, suggesting that diminished global strain better reflects clinical outcomes in this group. These thresholds may assist in the decision-making to transfer high-risk infants to ECMO centres.

Pressure Overload Creates Right Ventricular Diastolic Dysfunction in a Mouse Model: Assessment by Echocardiography

BACKGROUND

Noninvasive diagnostic tools for right ventricular (RV) dysfunction measurements are increasingly being used, although their association with the pathologic mechanisms of dysfunction is poorly understood. Although investigations have focused mainly on RV systolic function, RV diastolic function remains mostly neglected. The aim of this study was to test which echocardiographic parameters best reflect RV diastolic function in mice.

METHODS

Pulmonary artery banding (PAB) was used to induce RV pressure overload in mice. Transthoracic echocardiography and invasive hemodynamic measurements were performed after 3 weeks in PAB and sham-operated mice. Subsequently, the hearts were investigated by histology and analyzed for gene expression.

RESULTS

PAB-induced pressure overload (RV systolic pressure PAB 52.6 ± 11.8 mm Hg vs sham 27.0 ± 2.7 mm Hg) resulted in RV hypertrophy and remodeling, as reflected by increased Fulton index (PAB 0.37 ± 0.05 vs sham 0.25 ± 0.02, P = .001). Masson's trichrome staining revealed increased interstitial fibrosis (PAB 12.25 ± 3.12% vs sham 3.97 ± 1.58%, P = .002). This was associated with significant systolic RV dysfunction as demonstrated by reduced contractility index and diastolic dysfunction as demonstrated by end-diastolic pressure (PAB 2.66 ± 0.83 mm Hg vs sham 1.49 ± 0.50 mm Hg, P < .001) and τ (PAB 40.0 ± 16.1 msec vs sham 13.0 ± 3.5 msec, P < .001). Messenger ribonucleic acid expression of β-myosin heavy chain, atrial and brain natriuretic peptides, collagen family members was elevated, and the sarco/endoplasmic reticulum Ca(2+)-ATPase was decreased. Echocardiography revealed significant increases in RV free wall thickness and isovolumic relaxation time and a decrease in left ventricular eccentricity index, E', and tricuspid annular plane systolic excursion. Isovolumic relaxation time and E' were significantly correlated with end-diastolic pressure (rs = 0.511 and -0.451) and τ (rs = 0.739 and -0.445, respectively). Moreover, E' was negatively correlated with the degree of RV fibrosis (rs = -0.717).

CONCLUSIONS

Within 3 weeks, PAB causes pressure overload-induced RV hypertrophy and remodeling with compensated systolic and diastolic dysfunction in mice. RV free wall thickness, tricuspid annular plane systolic excursion, E', E/E' ratio, and isovolumic relaxation time appear to be the most reliable echocardiographic parameters for the assessment of RV dysfunction.

Chronic thromboembolic pulmonary hypertension in young woman with history of caesarian section

Chronic thromboembolic pulmonary hypertension (CTEPH) is one of subgroups of pulmonary hypertension. This is a serious medical condition that severely under diagnosed. CTEPH is commonly underdiagnosed due to non specific symptoms and lack of diagnostic tools. The aim of this presentation is to discuss the etiology, risk factors, diagnosis and management of CTEPH. A 36-year-old woman presented with easily fatigue and dyspneu on effort since two years ago. The symptom occured about three months after she gave birth with caesarian section due to preeclampsia. Further history taking, physical examination, electrocardiography (ECG) and echocardiography were highly suggestive of pulmonary hypertension. No deep vein thrombosis (DVT) was found on vascular femoral sonography. It was found after the lung perfusion scintigraphy performed that she actually had CTEPH. This patient was categorized as inoperable because CT pulmonary angiography showed no thrombus. The patient got pulmonary vasodilator and oral anticoagulant for lifelong.

The burden of pulmonary hypertension in resource-limited settings

Pulmonary vascular disease (PVD) is a significant global health problem and accounts for a substantial portion of cardiovascular disease in the developing world. Although there have been considerable advances in therapeutics for pulmonary arterial hypertension, over 97% of the disease burden lies within the developing world where there is limited access to health care and pharmaceuticals. The causes of pulmonary arterial hypertension differ between industrialized and developing nations. Infectious diseases-including schistosomiasis human immunodeficiency virus, and rheumatic fever-are common causes of PVD, as are hemoglobinopathies, and untreated congenital heart disease. High altitude and exposure to household air pollutants also contribute to a significant portion of PVD cases. Although diagnosis of pulmonary arterial hypertension requires the use of imaging and invasive hemodynamics, access to equipment may be limited. PVD therapies may be prohibitively expensive and limited to a select few. Prevention is therefore important in limiting the global PVD burden.

Abnormal echocardiography 7 days after stem cell transplantation may be an early indicator of thrombotic microangiopathy

Cardiac complications after hematopoietic stem cell transplantation (HSCT) can lead to significant morbidity and mortality. Cardiac evaluation during the first 100 days after HSCT is usually performed only if clinically indicated, and no studies have examined whether routine screening is beneficial in this patient population at high risk for tissue injury. We conducted a single-center prospective clinical study to screen for cardiac complications in pediatric and young adult patients. One hundred consecutive HSCT patients underwent scheduled echocardiographic screening on day +7 after transplantation, independent of their clinical condition. At least 1 abnormality was identified in 30% of cases. Seventeen children had a pericardial effusion, 13 elevated right ventricular pressure, and 3 reduced left ventricular function. Survival was reduced in children with any echocardiographic abnormality at day 7 (67% versus 80% in those with and without, respectively, abnormality, P = .073). Moreover, raised right ventricular pressure at day +7 was significantly associated with transplant-associated thrombotic microangiopathy (TA-TMA; P = .004) and may indicate early vascular injury in the lungs. These data suggest that echocardiography 7 days after HSCT can detect early cardiac complications of HSCT and may identify early vascular injury associated with TA-TMA.

Characterization of right ventricular remodeling and failure in a chronic pulmonary hypertension model

In pulmonary hypertension (PH), right ventricular (RV) dysfunction and failure is the main determinant of a poor prognosis. We aimed to characterize RV structural and functional differences during adaptive RV remodeling and progression to RV failure in a large animal model of chronic PH. Postcapillary PH was created surgically in swine (n = 21). After an 8- to 14-wk follow-up, two groups were identified based on the development of overt heart failure (HF): PH-NF (nonfailing, n = 12) and PH-HF (n = 8). In both groups, invasive hemodynamics, pressure-volume relationships, and echocardiography confirmed a significant increase in pulmonary pressures and vascular resistance consistent with PH. Histological analysis also demonstrated distal pulmonary arterial (PA) remodeling in both groups. Diastolic dysfunction, defined by a steeper RV end-diastolic pressure-volume relationship and longitudinal strain, was found in the absence of HF as an early marker of RV remodeling. RV contractility was increased in both groups, and RV-PA coupling was preserved in PH-NF animals but impaired in the PH-HF group. RV hypertrophy was present in PH-HF, although there was evidence of increased RV fibrosis in both PH groups. In the PH-HF group, RV sarcoplasmic reticulum Ca(2+)-ATPase2a expression was decreased, and endoplasmic reticulum stress was increased. Aldosterone levels were also elevated in PH-HF. Thus, in the swine pulmonary vein banding model of chronic postcapillary PH, RV remodeling occurs at the structural, histological, and molecular level. Diastolic dysfunction and fibrosis are present in adaptive RV remodeling, whereas the onset of RV failure is associated with RV-PA uncoupling, defective calcium handling, and hyperaldosteronism.

Relationship between echocardiographic and magnetic resonance derived measures of right ventricular size and function in patients with pulmonary hypertension

BACKGROUND

Transthoracic echocardiographic (TTE) imaging is the mainstay of clinical practice for evaluating right ventricular (RV) size and function, but its accuracy in patients with pulmonary hypertension has not been well validated.

METHODS

Magnetic resonance imaging (MRI) and TTE images were retrospectively reviewed in 40 consecutive patients with pulmonary hypertension. RV and left ventricular volumes and ejection fractions were calculated using MRI. TTE areas and indices of RV ejection fraction (RVEF) were compared.

RESULTS

The average age was 42 ± 12 years, with a majority of women (85%). There was a wide range of mean pulmonary arterial pressures (27-81 mm Hg) and RV end-diastolic volumes (111-576 mL), RVEFs (8%-67 %), and left ventricular ejection fractions (26%-72%) by MRI. There was a strong association between TTE and MRI-derived parameters: RV end-diastolic area (by TTE imaging) and RV end-diastolic volume (by MRI), R(2) = 0.78 (P < .001); RV fractional area change by TTE imaging and RVEF by MRI, R(2) = 0.76 (P < .001); and tricuspid annular plane systolic excursion by TTE imaging and RVEF by MRI, R(2) = 0.64 (P < .001). By receiver operating characteristic curve analysis, an RV fractional area change < 25% provided excellent discrimination of moderate systolic dysfunction (RVEF < 35%), with an area under the curve of 0.97 (P < .001). An RV end-diastolic area index of 18 cm(2)/m(2) provided excellent discrimination for moderate RV enlargement (area under the curve, 0.89; P < .001).

CONCLUSIONS

Echocardiographic estimates of RV volume (by RV end-diastolic area) and function (by RV fractional area change and tricuspid annular plane systolic excursion) offer good approximations of RV size and function in patients with pulmonary hypertension and allow the accurate discrimination of normal from abnormal.

Biomarkers for pediatric pulmonary arterial hypertension - a call to collaborate

Therapeutic approaches in pediatric pulmonary arterial hypertension (PAH) are based primarily on clinician experience, in contrast to the evidence-based approach in adults with pulmonary hypertension. There is a clear and present need for non-invasive and objective biomarkers to guide the accurate diagnosis, treatment, and prognosis of this disease in children. The multifaceted spectrum of disease, clinical presentation, and association with other diseases makes this a formidable challenge. However, as more progress is being made in the understanding and management of adult PAH, the potential to apply this knowledge to children has never been greater. This review explores the state of the art with regard to non-invasive biomarkers in PAH, with an eye toward those adult PAH biomarkers potentially suitable for application in pediatric PAH.

Expert consensus for performing right heart catheterisation for suspected pulmonary arterial hypertension in systemic sclerosis: a Delphi consensus study with cluster analysis

OBJECTIVE

To establish an expert consensus on which criteria are the most appropriate in clinical practice to refer patients with systemic sclerosis (SSc) for right heart catheterisation (RHC) when pulmonary hypertension (PH) is suspected.

METHODS

A three stage internet based Delphi consensus exercise involving worldwide PH experts was designed. In the first stage, a comprehensive list of domains and items combining evidence based indications and expert opinions were obtained. In the second and third stages, experts were asked to rate each item selected in the list. After each of stages 2 and 3, the number of items and criteria were reduced according to a cluster analysis.

RESULTS

A literature search and the opinions of 47 experts participating in Delphi stage 1 provided a list of seven domains containing 142 criteria. After stages 2 and 3, these domains and tools were reduced to three domains containing eight tools: clinical (progressive dyspnoea over the past 3 months, unexplained dyspnoea, worsening of WHO dyspnoea functional class, any finding on physical examination suggestive of elevated right heart pressures and any sign of right heart failure), echocardiography (systolic pulmonary artery pressure >45 mm Hg and right ventricle dilation) and pulmonary function tests (diffusion lung capacity for carbon monoxide <50% without pulmonary fibrosis).

CONCLUSIONS

Among experts in pulmonary arterial hypertension-SSc, a core set of criteria for clinical practice to refer SSc patients for RHC has been defined by Delphi consensus methods. Although these indications are recommended by this expert group to be used as an interim tool, it will be necessary to formally validate the present tools in further studies.

Right ventricular function impaired in children and adolescents with severe idiopathic scoliosis

BACKGROUND

Although it is speculated that scoliosis may induce cardiac dysfunction, there is no report about evaluation of cardiac function, especially right cardiac function in patients with scoliosis. Therefore, we evaluated right ventricular function in idiopathic scoliotic patients with mild to severe curves and compared them with healthy children and adolescents matched in age, then explored relationship between scoliosis and right ventricular function.

METHODS

Thirty-seven patients diagnosed with idiopathic scoliosis with a mean age of 16y/o (range, 8-25y/o) and an average spine curve of 77.5°Cobb (range, 30-157°) were studied by echocardiography. TAD was obtained using M-mode echocardiography. Similar examination was performed in a control group of 17 healthy individuals in matched-age. According to the different curve degree, all patients were divided into 3 groups (mild, moderate and severe). Comparison was done among the groups and the relationship between TAD and spine curve of Cobb was analyzed.

RESULTS

Patients with severe scoliosis showed depressed TAD. There was good correlation between TAD and spine curve of Cobb.

CONCLUSIONS

Patients with severe scoliosis showed a significant lower right ventricular systolic function.

Pulmonary Hypertension in Idiopathic Pulmonary Fibrosis

Idiopathic pulmonary fibrosis (IPF) is a fatal lung disease with a variable natural history. Pulmonary hypertension (PH) is frequently found in patients with IPF and is associated with an almost 3-fold increase in the risk of death. Pulmonary hypoxic vasoconstriction plays an important role in the pathogenesis of PH in IPF (PH-IPF), although it has become clear that it is not the only mechanism involved. While invasive right heart catheterization is the gold standard modality of hemodynamic assessment, there has been increasing interest in noninvasive testing, such as Doppler echocardiogram, as complementary methods of assessing right ventricular function in these patients. While the expanding array of pharmacologic options for the treatment of pulmonary arterial hypertension has engendered increased interest in the application of these therapies for PH-IPF, supportive evidence for benefit is lacking.

Developing a heart score: next steps

The meeting of the Advisory Board of Experts in Pulmonary Hypertension (ABEPH) in 2011 discussed the potential development of a prognostic score for pulmonary arterial hypertension (PAH) based on parameters associated with right ventricular function. During the discussion, a shortlist of parameters derived from hemodynamic, echocardiography, magnetic resonance imaging, and biomarker analysis was developed. This shortlist is the starting point for developing a score that reflects heart function; such a score could have potential in the future clinical management of patients with PAH.

Cardiovascular modeling in pulmonary arterial hypertension: focus on mechanisms and treatment of right heart failure using the CircAdapt model

In recent years, increased understanding of cardiovascular system dynamics has led to the development of mathematical models of the heart and circulation. Models that enable realistic simulation of ventricular mechanics and interactions under a range of conditions have the potential to provide an ideal method with which to investigate the effects of pulmonary arterial hypertension and its treatment on cardiac mechanics and hemodynamics. Such mathematical models have the potential to contribute to a personalized, patient-specific treatment approach and allow more objective diagnostic decision-making, patient monitoring, and assessment of treatment outcome. This review discusses the development of mathematical models of the heart and circulation, with particular reference to the closed-loop CircAdapt model, and how the model performs under both normal and pathophysiological (pulmonary hypertensive) conditions.