Pulmonary endarterectomy: the potentially curative treatment for patients with chronic thromboembolic pulmonary hypertension

Feasibility of a Noninvasive Operability Assessment in Chronic Thromboembolic Pulmonary Hypertension under Real-World Practice

This study aimed to evaluate the feasibility of a noninvasive operability assessment of chronic thromboembolic pulmonary hypertension (CTEPH) based on multidetector computed tomographic angiography (MCTA). Up to 176 patients were evaluated from January 2016 to April 2018. Throughout the first phase, the initial surgical decision was made based on MCTA with further analysis of pulmonary angiography (PA) in order to evaluate in which cases the initial decision was not modified by PA. During the second phase, PA was limited to patients judged inoperable based on MCTA or those whose assessment was not possible. Patients deemed operable (50%) based on MCTA along the first phase had been adequately classified, as PA did not modify the initial decision in all but one patient. Comparable results were obtained throughout the implementation phase. Regarding operated patients, the decision of operability was based solely on MCTA in 94% of those with level I disease, in 75% with level II, and 54% with level III. This approach enabled shorter periods of time to complete surgical assessment and the avoidance of PA-related morbidity. Baseline parameters, postoperative measures, and survival rates at 1 year after surgery were comparable in both phases. Noninvasive operability assessment is feasible in a subset of CTEPH patients and optimizes surgical candidacy evaluation.

Plasma metabolomics exhibit response to therapy in chronic thromboembolic pulmonary hypertension

Pulmonary hypertension is a condition with limited effective treatment options. Chronic thromboembolic pulmonary hypertension (CTEPH) is a notable exception, with pulmonary endarterectomy (PEA) often proving curative. This study investigated the plasma metabolome of CTEPH patients, estimated reversibility to an effective treatment and explored the source of metabolic perturbations.We performed untargeted analysis of plasma metabolites in CTEPH patients compared to healthy controls and disease comparators. Changes in metabolic profile were evaluated in response to PEA. A subset of patients were sampled at three anatomical locations and plasma metabolite gradients calculated.We defined and validated altered plasma metabolite profiles in patients with CTEPH. 12 metabolites were confirmed by receiver operating characteristic analysis to distinguish CTEPH and both healthy (area under the curve (AUC) 0.64-0.94, all p<2×10^-5) and disease controls (AUC 0.58-0.77, all p<0.05). Many of the metabolic changes were notably similar to those observed in idiopathic pulmonary arterial hypertension (IPAH). Only five metabolites (5-methylthioadenosine, N1-methyladenosine, N1-methylinosine, 7-methylguanine, N-formylmethionine) distinguished CTEPH from chronic thromboembolic disease or IPAH. Significant corrections (15-100% of perturbation) in response to PEA were observed in some, but not all metabolites. Anatomical sampling identified 188 plasma metabolites, with significant gradients in tryptophan, sphingomyelin, methionine and Krebs cycle metabolites. In addition, metabolites associated with CTEPH and gradients showed significant associations with clinical measures of disease severity.We identified a specific metabolic profile that distinguishes CTEPH from controls and disease comparators, despite the observation that most metabolic changes were common to both CTEPH and IPAH patients. Plasma metabolite gradients implicate cardiopulmonary tissue metabolism of metabolites associated with pulmonary hypertension and metabolites that respond to PEA surgery could be a suitable noninvasive marker for evaluating future targeted therapeutic interventions.

Platelet count trends and response to fondaparinux in a cohort of heparin-induced thrombocytopenia suspected patients after pulmonary endarterectomy

A definitive diagnosis of heparin-induced thrombocytopenia (HIT) is difficult to make, especially in patients undergoing cardiac surgery. In this retrospective cohort study, we assessed the platelet count trends and the response to fondaparinux in a population of patients of suspected HIT after pulmonary endarterectomy (PEA). Patients enrolled in this study were over the age of 18 years, and survived longer than 7 days after PEA between January 1, 2011 and December 31, 2015. HIT likelihood was assessed by the 4 T's score and interpreted by our institutional algorithm. 54 patients were operated, and 49 patients met the inclusion criteria. Six patients met the criteria for suspected HIT and were treated with fondaparinux until the platelet recovered. No significant difference was observed of clinical characteristics between intermediate to high HIT likelihood patients (HIT SUSPECTED) and low HIT likelihood patients (NO HIT SUSPECTED). HIT SUSPECTED patients reached platelet count lowest later (about 5.5 days after PEA), while NO HIT SUSPECTED patients is about 4.0 days after PEA. Percentage of platelet counts decrease (> 50%) was larger than NO HIT SUSPECTED patients (< 50%). There was no difference in mortality or residual pulmonary hypertension between HIT SUSPECTED and NO HIT SUSPECTED patients. Two HIT SUSPECTED patients who used heparin after PEA died, the other four survived by replacing heparin or low molecular weight heparin with fondaparinux. Suspected HIT patients should be surveilled carefully. Platelet counts trends may have some hints in the prevention of HIT. Fondaparinux may be effective for patients with suspected HIT.

Safety and effectiveness of riociguat for chronic thromboembolic pulmonary hypertension in real-world clinical practice: interim data from post-marketing surveillance in Japan

This multicenter, prospective, non-interventional study (ClinicalTrials.gov: NCT02117791) evaluated the safety and effectiveness of riociguat for chronic thromboembolic pulmonary hypertension in Japanese clinical practice, registering all patients with chronic thromboembolic pulmonary hypertension treated with riociguat following its launch in Japan in April 2014. Safety was assessed by analyzing the adverse drug reactions. Effectiveness measurements included the assessment of change in World Health Organization functional class, six-minute walk test, and hemodynamics. Overall, 1031 patients were included in the safety analysis with 811 (78.7%) patients in World Health Organization functional class II/III. The mean treatment duration was 591.4 days (median 441.0 days). Adverse drug reactions were reported in 19.5% of patients, the most common being hypotension (5.9%), headache (3.0%), dizziness (1.9%), and gastroesophageal reflux disease (1.5%). Serious adverse drug reactions were reported in 2.1% of patients. Estimated survival was 97.0% at one year, 95.8% at two years, and 94.4% at three years. The effectiveness analysis (n = 1027) showed significant increases from baseline in six-minute walking distance, and significant reductions from baseline in mean pulmonary arterial pressure and pulmonary vascular resistance. These interim results of riociguat in Japanese patients with chronic thromboembolic pulmonary hypertension demonstrated a safety profile that was generally consistent with those of pivotal clinical studies. The study is ongoing, and will continue to provide insights into the safety and effectiveness of riociguat in real-world practice.

Chronic thromboembolic pulmonary hypertension - still evolving

Chronic thromboembolic pulmonary hypertension (CTEPH) is one of the leading causes of severe pulmonary hypertension (PH). The disease is still underdiagnosed, and the true prevalence is unknown. CTEPH is characterized by intraluminal non-resolving thrombus organization and fibrous stenosis, or complete obliteration of pulmonary arteries, promoted by progressive remodeling of the pulmonary vasculature. One consequence of this is an increase in pulmonary vascular resistance and pressure, resulting in PH and progressive right heart failure, leading to death if left untreated.

Endovascular disobliteration by pulmonary endarterectomy (PEA) is the preferred treatment for CTEPH patients. PEA surgery is the only technique that can potentially cure CTEPH disease, especially in patients with fresh or organized thrombi of the proximal branches of pulmonary arteries. However, not all patients are eligible for PEA surgery. Recent research has provided evidence suggesting balloon pulmonary angioplasty (BPA) and targeted medical therapy as additional promising available treatments options for inoperable CTEPH and recurrent/persistent PH after PEA surgery.

Studies on BPA have shown it to improve pulmonary hemodynamics, symptoms, exercise capacity and RV function in inoperable CTEPH. Subsequently, BPA has developed into an essential component of the modern era of CTEPH treatment. Large randomized controlled trials have demonstrated varying significant improvements with targeted medical therapy in technically inoperable CTEPH patients. Thus, treatment of CTEPH requires a comprehensive multidisciplinary assessment, including an experienced PEA surgeon, PH specialist, BPA interventionist and CTEPH-trained radiologist at expert centers. In this comprehensive review, we address the latest developments in the fast-evolving field of CTEPH. These include advancements in imaging modalities and developments in operative and interventional techniques, which have widened the range of patients who may benefit from these procedures. The efficacy and safety of targeted medical therapies in CTEPH patients are also discussed. As the treatment options for CTEPH improve, hybrid management involving multiple treatments in the same patient may become a viable option in the near future.

Life expectancy after pulmonary endarterectomy for chronic thromboembolic pulmonary hypertension: a Swedish single-center study

Pulmonary endarterectomy is the guideline recommended treatment for chronic thromboembolic pulmonary hypertension, in addition to life-long anticoagulation therapy. The aim was to analyze long-term relative survival after pulmonary endarterectomy for chronic thromboembolic pulmonary hypertension. We included all patients who underwent pulmonary endarterectomy for chronic thromboembolic pulmonary hypertension at Karolinska University Hospital between 1997 and 2018 (n = 100). We obtained baseline characteristics and vital status from patient charts and national health-data registers. The expected survival from the general Swedish population matched by age, sex, and year of surgery was obtained from the Human Mortality Database. The relative survival was used as an estimate of cause-specific mortality. The mean age of the patients was 62 years and 39% were women. Most patients were severely symptomatic (95% in New York Heart Association functional class III-IV), and mean preoperative systolic/diastolic (mean) pulmonary artery pressure was 78/27 (45) mmHg. The mean and maximum follow-up time was 7.2 and 22.1 years, respectively. Early (30-day) mortality was 7%. The 15-year observed, expected, and relative survival was 55% (95% confidence interval, 40%-68%), 71%, and 77% (95% confidence interval, 56%-95%), respectively. The 15-year relative survival conditional on 30-day survival was 83% (95% confidence interval, 60%-100%). Although the life expectancy following pulmonary endarterectomy was shorter compared to the general population, the difference was small in those who survived the operation and the early postoperative period. Patients with chronic thromboembolic pulmonary hypertension who are surgical candidates should undergo pulmonary endarterectomy to improve prognosis.

Long-term health-related quality of life after surgery in patients with chronic thromboembolic pulmonary hypertension

PURPOSE

To assess the dynamic of various health-related quality of life (HRQoL) parameters 3 years after pulmonary thromboendarterectomy (PTE), and to identify factors affecting HRQoL parameters in patients with chronic thromboembolic pulmonary hypertension (CTEPH) in the long-term follow-up after surgery.

METHODS

This prospective cohort study included 128 patients with CTEPH before and after the PTE (3 year follow-up). The HRQoL was examined using the Short-Form 36 Health Survey Questionnaire (SF-36).

RESULTS

In patients with CTEPH 3 years after PTE, a significant improvement in all the HRQoL parameters. The summary indicators of the physical and mental components of health remained at the same level as 1 year after the PTE and did not exceed 50 points. The residual pulmonary hypertension was a leading factor limiting parameters of physical and mental health 3 years after a PTE. In addition, the parameters of physical activity were adversely affected by age and the age-adjusted Charlson Comorbidity Index.

CONCLUSIONS

In the study group of patients with CTEPH, PTE contributes to a significant improvement in all HRQoL parameters, which observed both 1 year and 3 years after surgery. The leading factor adversely affecting the physical and emotional components of health in the long-term period after PTE was residual pulmonary hypertension recorded in the early postoperative period. In addition, some physical HRQoL parameters are affected by age and age-adjusted Charlson Comorbidity Index.

Riociguat Improves Pulmonary Hemodynamics in Patients with Inoperable Chronic Thromboembolic Pulmonary Hypertension

Background

Few studies have investigated the effects of riociguat on pulmonary hemodynamics in Asian patients with chronic thromboembolic pulmonary hypertension (CTEPH). In this study, we evaluated the effects of riociguat on pulmonary hemodynamics in inoperable CTEPH patients.

Methods

We retrospectively collected the clinical data of 11 inoperable CTEPH patients. Pulmonary hemodynamic parameters of right heart catheterization, echocardiography, 6-minute walk distance and World Health Organization (WHO) functional class were assessed at baseline and after riociguat treatment.

Results

The median duration of riociguat treatment was 12 months, and all 11 patients tolerated riociguat 7.5 mg/day well after titration. With regards to pulmonary hemodynamic data, both mean pulmonary artery pressure and pulmonary vascular resistance significantly decreased from 41 ± 8 mmHg to 38 ± 9 mmHg (p = 0.045) and 787 ± 417 dyn·s·cm^-5 to 478 ± 267 dyn·s·cm^-5 (p = 0.007), respectively. With regards to clinical symptoms, WHO functional class significantly improved in nine of the 11 patients, and there was no change in the other two patients (p = 0.004). In addition, the median level of N-terminal pro-brain natriuretic peptide also significantly decreased from 281 (117-5943) pg/ml to 226 (48-1276) pg/ml (p = 0.021).

Conclusions

Riociguat treatment improved both clinical symptoms and pulmonary hemodynamics in the inoperative CTEPH patients in this study.

Sex-specific differences in chronic thromboembolic pulmonary hypertension. Results from the European CTEPH registry

BACKGROUND

Women are more susceptible than men to several forms of pulmonary hypertension, but have better survival. Sparse data are available on chronic thromboembolic pulmonary hypertension (CTEPH).

METHODS

We investigated sex-specific differences in the clinical presentation of CTEPH, performance of pulmonary endarterectomy (PEA), and survival.

RESULTS

Women constituted one-half of the study population of the European CTEPH registry (N = 679) and were characterized by a lower prevalence of some cardiovascular risk factors, including prior acute coronary syndrome, smoking habit, and chronic obstructive pulmonary disease, but more prevalent obesity, cancer, and thyroid diseases. The median age was 62 (interquartile ratio, 50-73) years in women and 63 (interquartile ratio, 53-70) in men. Women underwent PEA less often than men (54% vs 65%), especially at low-volume centers (48% vs 61%), and were exposed to fewer additional cardiac procedures, notably coronary artery bypass graft surgery (0.5% vs 9.5%). The prevalence of specific reasons for not being operated, including patient's refusal and the proportion of proximal vs distal lesions, did not differ between sexes. A total of 57 (17.0%) deaths in women and 70 (20.7%) in men were recorded over long-term follow-up. Female sex was positively associated with long-term survival (adjusted hazard ratio, 0.66; 95% confidence interval, 0.46-0.94). Short-term mortality was identical in the two groups.

CONCLUSIONS

Women with CTEPH underwent PEA less frequently than men, especially at low-volume centers. Furthermore, they had a lower prevalence of cardiovascular risk factors and were less often exposed to additional cardiac surgery procedures. Women had better long-term survival.

Preoperative platelet count, preoperative hemoglobin concentration and deep hypothermic circulatory arrest duration are risk factors for acute kidney injury after pulmonary endarterectomy: a retrospective cohort study

Background

Acute kidney injury (AKI) is a major postoperative morbidity of patients undergoing cardiac surgery and has a negative effect on prognosis. The kidney outcomes after pulmonary endarterectomy (PEA) have not yet been reported; However, several perioperative characteristics of PEA may induce postoperative AKI. The objective of our study was to identify the incidence and risk factors for postoperative AKI and its association with short-term outcomes.

Methods

This was a single-center, retrospective, observational, cohort study. Assessments of AKI diagnosis was executed based on the Kidney Disease Improving Global Outcomes (KDIGO) criteria.

Results

A total of 123 consecutive patients who underwent PEA between 2014 and 2018 were included.

The incidence of postoperative AKI was 45% in the study population. Stage 3 AKI was associated with worse short-term outcomes and 90-day mortality (p < 0.001, p = 0.002, respectively). The independent predictors of postoperative AKI were the preoperative platelet count (OR 0.992; 95%CI 0.984–0.999; P = 0.022), preoperative hemoglobin concentration (OR 0.969; 95%CI 0.946–0.993; P = 0.01) and deep hypothermic circulatory arrest (DHCA) time (OR 1.197; 95%CI 1.052–1.362; P = 0.006) in the multivariate analysis.

Conclusion

The incidence of postoperative AKI was relatively high after PEA compared with other types of cardiothoracic surgeries. The preoperative platelet count, preoperative hemoglobin concentration and DHCA duration were modifiable predictors of AKI, and patients may benefit from some low-risk, low-cost perioperative measures.

Chronic thromboembolic pulmonary hypertension is a clot you cannot swat

A 49-year-old man with progressive dyspnea on exertion and a remote history of syncope presented with hypotension and acute right ventricular failure, and was ultimately diagnosed with acute pulmonary embolism. Laboratory data revealed a prolonged activated partial thromboplastin time, which confounded treatment options. He was ultimately diagnosed with anti-phospholipid syndrome and factor XII deficiency, and underwent a thromboendarterectomy procedure with resolution of right ventricular failure and symptoms. Careful attention to history, initial physical examination manifestations, and clinical data often permit a timely diagnosis of and treatment for chronic thromboembolic pulmonary hypertension.

Impact of pulmonary endarterectomy on pulmonary arterial wave propagation and reservoir function

High wave speed and large wave reflection in the pulmonary artery have previously been reported in patients with chronic thromboembolic pulmonary hypertension (CTEPH). We assessed the impact of pulmonary endarterectomy (PEA) on pulmonary arterial wave propagation and reservoir function in patients with CTEPH. Right heart catheterization was performed using a combined pressure and Doppler flow sensor-tipped guidewire to obtain simultaneous pressure and flow velocity measurements in the pulmonary artery in eight patients with CTEPH before and 3 mo after PEA. Wave intensity and reservoir-excess pressure analyses were then performed. Following PEA, mean pulmonary arterial pressure (PAPm; ∼49 vs. ∼32 mmHg), pulmonary vascular resistance (PVR; ∼11.1 vs. ∼5.1 Wood units), and wave speed (∼16.5 vs. ∼8.1 m/s), i.e., local arterial stiffness, markedly decreased. The changes in the intensity of the reflected arterial wave and wave reflection index (pre: ∼28%; post: ∼22%) were small, and patients post-PEA with and without residual pulmonary hypertension (i.e., PAPm ≥ 25 mmHg) had similar wave reflection index (∼20 vs. ∼23%). The reservoir and excess pressure decreased post-PEA, and the changes were associated with improved right ventricular afterload, function, and size. In conclusion, although PVR and arterial stiffness decreased substantially following PEA, large wave reflection persisted, even in patients without residual pulmonary hypertension, indicating lack of improvement in vascular impedance mismatch. This may continue to affect the optimal ventriculoarterial interaction, and further studies are warranted to determine whether this contributes to persistent symptoms in some patients.NEW & NOTEWORTHY We performed wave intensity analysis in the pulmonary artery in patients with chronic thromboembolic pulmonary hypertension before and 3 mo after pulmonary endarterectomy. Despite substantial reduction in pulmonary arterial pressures, vascular resistance, and arterial stiffness, large pulmonary arterial wave reflection persisted 3 mo postsurgery, even in patients without residual pulmonary hypertension, suggestive of lack of improvement in vascular impedance mismatch.

Effectiveness of balloon pulmonary angioplasty in patients with inoperable chronic thromboembolic pulmonary hypertension despite having lesion types suitable for surgical treatment

BACKGROUND

Balloon pulmonary angioplasty (BPA) has been performed in patients with inoperable chronic thromboembolic pulmonary hypertension (CTEPH). However, some patients have inoperable CTEPH despite having lesions suitable for surgical treatment. The effectiveness of BPA in such cases is unclear. The aim of this study was to clarify the effectiveness of BPA in these cases.

METHODS

We retrospectively investigated patients with inoperable CTEPH and divided them into two groups: BPA-suitable and BPA-unsuitable groups based on the findings of pulmonary angiography, computed tomography, and perfusion scintigraphy. The BPA-unsuitable group included patients whose lesions are suitable for surgical treatment but who did not undergo the procedure for any specified reason. We analyzed the hemodynamic, respiratory, and functional status of the patients before and after BPA.

RESULTS

Forty-three consecutive patients with inoperable CTEPH (age, 62.6 ± 13.5 years; 31 women) were included; all of them underwent BPA. There were 10 patients in the BPA-unsuitable group. In all patients, the mean pulmonary artery pressure, pulmonary vascular resistance, arterial oxygen saturation level, and 6-min walking distance significantly improved after BPA (mean pulmonary artery pressure, from 43.3 ± 7.8 mmHg to 23.9 ± 4.7 mmHg; pulmonary vascular resistance, from 924.1 ± 462.2 dynes/s/cm^-5 to 319.7 ± 163.8 dynes/s/cm^-5; arterial oxygen saturation level, from 89.3 ± 4.3% to 93.4 ± 3.3%; 6-min walking distance, from 370.0 ± 107.4 m to 443.8 ± 101.4 m). Notably, none of the parameters significantly differed between the groups after BPA. Importantly, the amount of lung bleeding did not differ between them. However, several sessions were required in the BPA-unsuitable group (BPA-unsuitable group: six sessions vs. BPA-suitable group: four sessions).

CONCLUSIONS

BPA safely improved the hemodynamic and functional statuses of the patients with CTEPH who are judged as inoperable for any reason despite lesion being suitable for surgical treatment. However, numerous BPA sessions were required in these patients.

Balloon pulmonary angioplasty vs riociguat in patients with inoperable chronic thromboembolic pulmonary hypertension: A systematic review and meta-analysis

Backgrounds

No previous meta‐analyses have compared the efficacy and safety of BPA with riociguat therapy in inoperable CTEPH patients.

Methods

Relevant published studies were searched in the PubMed, Embase and ClinicalTrial.gov databases.

Results

Twenty‐three clinical trials including 1454 patients (631 underwent BPA; 823 underwent riociguat therapy) were analyzed. BPA was associated with a greater improvement in RAP (mean difference (MD) = −3.53 mmHg, 95% CI: [−4.85, −2.21] vs MD = −1.05 mmHg, 95% CI: [−1.82, −0.29]); mPAP (MD = −15.02 mmHg, 95% CI: [−17.32, −12.71] vs MD = −4.19 mmHg, 95% CI: [−5.58, −2.80]); PVR (standard MD = −1.32 woods, 95% CI: [−1.57, −1.08] vs standard MD = −0.65 woods, 95% CI: [−0.79, −0.50]); NYHA functional class (RR = 6.78, 95% CI: [3.14, 14.64] vs RR = 1.49, 95% CI: [1.07, 2.07]); and 6MWD (MD = 71.66 m, 95% CI: [58.34, 84.99] vs MD = 45.25 m, 95% CI: [36.51, 53.99]) than riociguat treatment. However, the increase in CO was greater with riociguat (MD = 0.78 L/min, 95% CI: [0.61, 0.96]) than with BPA (MD = 0.33 L/min, 95% CI: [0.06, 0.59]). No significant difference in cardiac index (CI) was found between BPA (MD = 0.40 L/min/m², 95% CI: [0.21, 0.58]) and riociguat (MD = 0.40 L/min/m², 95% CI: [0.26, 0.54]). The most common complications of BPA were pulmonary injury (0.3%‐5.6%) and pulmonary edema (0.8%‐28.6%). The most common adverse events of riociguat were headache, dizziness, hypotension and nasopharyngitis.

Conclusions

Our meta‐analysis indicates that BPA might be associated with greater improvements in exercise tolerance and pulmonary hemodynamics except for cardiac output and cardiac index than riociguat therapy. However, both of them were well tolerated.

Risk assessment in pulmonary arterial hypertension and chronic thromboembolic pulmonary hypertension

Background

Current pulmonary hypertension treatment guidelines recommend use of a risk stratification model encompassing a range of parameters, allowing patients to be categorised as low, intermediate or high risk. Three abbreviated versions of this risk stratification model were previously evaluated in patients with pulmonary arterial hypertension (PAH) in the French, Swedish and COMPERA registries. Our objective was to investigate the three abbreviated risk stratification methods for patients with mostly prevalent PAH and chronic thromboembolic pulmonary hypertension (CTEPH), in patients from the PATENT-1/2 and CHEST-1/2 studies of riociguat.

Methods

Risk was assessed at baseline and at follow-up in PATENT-1 and CHEST-1. Survival and clinical worsening-free survival were assessed in patients in each risk group/strata.

Results

With all three methods, riociguat improved risk group/strata in patients with PAH after 12 weeks. The French non-invasive and Swedish/COMPERA methods discriminated prognosis for survival and clinical worsening-free survival at both baseline and follow-up. Furthermore, patients achieving one or more low-risk criteria or a low-risk stratum at follow-up had a significantly reduced risk of death and clinical worsening compared with patients achieving no low-risk criteria or an intermediate-risk stratum. Similar results were obtained in patients with inoperable or persistent/recurrent CTEPH.

Conclusions

This analysis confirms and extends the results of the registry analyses, supporting the value of goal-oriented treatment in PAH. Further assessment of these methods in patients with CTEPH is warranted.

Riociguat improves risk group in patients with PAH and CTEPH according to three abbreviated versions of the ESC/ERS risk stratification model (results of a post hoc analysis)http://ow.ly/Herk30o8lKM

Chronic thromboembolic pulmonary hypertension (CTEPH): what do we know about it? A comprehensive review of the literature

: Chronic thromboembolic disease (CTED), especially when associated with pulmonary hypertension (CTEPH), is a fearsome and under-diagnosed but potentially curable complication of pulmonary embolism, thanks to recent therapeutic options. Aspecific symptoms and signs make its diagnosis challenging, requiring clinicians to be ready to suspect its presence in patients with dyspnea of unknown origin or persistent symptoms after acute pulmonary embolism. The aim of this review is to provide an update to the general practitioner or the specialist physician on the state of the art regarding the epidemiology, pathophysiology and clinical management of chronic thromboembolic syndromes.

The outcome of reoperative pulmonary endarterectomy surgery

OBJECTIVES

Pulmonary endarterectomy (PEA) is the treatment of choice for patients with chronic thromboembolic pulmonary hypertension (PH). Despite excellent outcomes following PEA, a small proportion of patients have residual proximal disease or present with recurrent chronic thromboembolic PH and may benefit from further surgery. The aim of this study was to analyse outcomes following reoperative PEA at a high-volume national tertiary referral centre for the management of chronic thromboembolic PH.

METHODS

This retrospective analysis was performed using our prospectively maintained PH database to identify all patients who underwent reoperative PEA surgery between the commencement of the programme in 1997 and January 2017, and the patients' data were collected for analysis.

RESULTS

Twelve patients underwent reoperative PEA during the period of study. The mean interval between primary procedure and reoperative procedure was 6.3 years. Significant improvements were observed in pulmonary haemodynamics following reoperative PEA. Mean pulmonary arterial pressure decreased from 46.8 to 29.8 mmHg (P < 0.0001) and pulmonary vascular resistance decreased from 662 to 362 dyne·s·cm-5 (P = 0.0007). A significant functional improvement in the 6-min walking test distance was also observed, increasing from 327 to 460 m at 6 months postoperatively (P = 0.0018). Median length of hospital stay was 12 days. In-hospital mortality was 8.3% with 1-year survival of 83.3%.

CONCLUSIONS

Reoperative PEA is technically possible and relatively safe, achieving good functional and physiological outcomes. Patients must be carefully selected by a multidisciplinary team, and surgery should be performed in experienced centres.

Identifying chronic thromboembolic pulmonary hypertension through the French national hospital discharge database

Chronic thromboembolic pulmonary hypertension (CTEPH), a rare pulmonary vascular disease, is often misdiagnosed due to nonspecific symptoms. The objective of the study was to develop, refine and validate a case ascertainment algorithm to identify CTEPH patients within the French exhaustive hospital discharge database (PMSI), and to use it to estimate the annual number of hospitalized patients with CTEPH in France in 2015, as a proxy for disease prevalence. As ICD-10 coding specifically for CTEPH was not available at the time of the study, a case ascertainment algorithm was developed in close collaboration with an expert committee, using a two-step process (refinement and validation), based on matched data from PMSI and hospital medical records from 2 centres. The best-performing algorithm (specificity 95%, sensitivity 70%) consisted of ≥1 pulmonary hypertension (PH) diagnosis during 2015 and any of the following criteria over 2009-2015: (i) CTEPH interventional procedure, (ii) admission for PH and pulmonary embolism (PE), (iii) PE followed by hospitalization in competence centre then in reference centre, (iv) history of PE and right heart catheterization. Patients with conditions suggestive of pulmonary arterial hypertension were excluded. A total of 3,138 patients hospitalized for CTEPH was estimated for 2015 (47 cases/million, range 43 to 50 cases/million). Assuming that patients are hospitalized at least once a year, the present study provides an estimate of the minimal prevalence of CTEPH and confirms the heavy burden of this disease.

Metabolic Alterations in Cardiopulmonary Vascular Dysfunction

Cardiovascular diseases (CVD) are the leading cause of death worldwide. CVD comprise a range of diseases affecting the functionality of the heart and blood vessels, including acute myocardial infarction (AMI) and pulmonary hypertension (PH). Despite their different causative mechanisms, both AMI and PH involve narrowed or blocked blood vessels, hypoxia, and tissue infarction. The endothelium plays a pivotal role in the development of CVD. Disruption of the normal homeostasis of endothelia, alterations in the blood vessel structure, and abnormal functionality are essential factors in the onset and progression of both AMI and PH. An emerging theory proposes that pathological blood vessel responses and endothelial dysfunction develop as a result of an abnormal endothelial metabolism. It has been suggested that, in CVD, endothelial cell metabolism switches to higher glycolysis, rather than oxidative phosphorylation, as the main source of ATP, a process designated as the Warburg effect. The evidence of these alterations suggests that understanding endothelial metabolism and mitochondrial function may be central to unveiling fundamental mechanisms underlying cardiovascular pathogenesis and to identifying novel critical metabolic biomarkers and therapeutic targets. Here, we review the role of the endothelium in the regulation of vascular homeostasis and we detail key aspects of endothelial cell metabolism. We also describe recent findings concerning metabolic endothelial cell alterations in acute myocardial infarction and pulmonary hypertension, their relationship with disease pathogenesis and we discuss the future potential of pharmacological modulation of cellular metabolism in the treatment of cardiopulmonary vascular dysfunction. Although targeting endothelial cell metabolism is still in its infancy, it is a promising strategy to restore normal endothelial functions and thus forestall or revert the development of CVD in personalized multi-hit interventions at the metabolic level.

Pulmonary Endarterectomy in Latvia: A National Experience

Background and objectives: Chronic thromboembolic pulmonary hypertension (CTEPH) is a hemodynamic state characterized by chronic obstruction in pulmonary circulation. The treatment of choice is pulmonary endarterectomy (PEA). The aim of our study was to compile and analyze the data of a small, national center, which has not yet been done in the Baltic states. Materials and methods: The data of Latvian CTEPH registry in timeframe from 1 September 2007 to 31 December 2016 was retrospectively analyzed and all patients who underwent PEA were included. Results: PEA was done for 7 patients. The in-hospital mortality was 14%. The 3-year survival rate was 86%. The procedure restored pulmonary blood pressure to normal values for three of the patients (42%). The remaining four patients (57%) had persistent pulmonary hypertension (mPAP > 30 mmHg), which required continuous therapy. There was a comparable decline in mean mPAP compared to baseline, 53.4 ± 14.4 mmHg to 44.3 ± 30 mmHg, respectively. At 12-month follow-up, there was a significant improvement in functional capacity, as seen by increased 6-min walk test distance and shifts in New York Heart Association functional class. Conclusions: Only 16% of all prevalent Latvian CTEPH patients have underwent PEA in the course of nine years, despite it being the treatment of choice for CTEPH. As PEA and other emerging treatment options, such as balloon pulmonary angioplasty, can only be done in expert centers, numerous organizational, logistical, and economic issues arise for patients of smaller countries, where such centers have not yet been created due to lack of experience and limited amount of patients.

Venous thromboembolism prophylaxis using the Caprini score

Venous thromboembolism (VTE) including pulmonary embolism (PE) and deep vein thrombosis (DVT) is one of the leading causes of preventable cardiovascular disease in the United States (US) and is the number one preventable cause of death following a surgical procedure. Post-operative VTE is associated with multiple short and long-term complications. We will focus on reviewing the many faces of VTE in detail as they represent common challenging scenarios in clinical practice.

Methods of Pharmacological Treatment of Chronic Thromboembolic Pulmonary Hypertension Current Approaches to the Patients Management

In this paper we have discussed epidemiology, pathogenesis, and approaches to treatment of chronic thromboembolic pulmonary hypertension (CTEPH). CTEPH is a unique potentially curable form of pulmonary hypertension. The gold standard of CTEPH treatment is pulmonary thromboendarterectomy. However, about 40% of patients with CTEPH are inoperable due to distal surgically inaccessible lesions of the pulmonary vasculature, severe hemodynamic impairments, or other contraindications. In addition, nearly half of patients have persistent or recurrent pulmonary hypertension following surgery. Current guidelines support the use of pharmacotherapy in these patients. In the article we have presented results of main clinical studies of targeted drugs therapy (endothelin receptor antagonists, prostanoids, phosphodiesterase type 5 inhibitors, soluble guanylate cyclase stimulators) of patients with CTEPH. The only drug that has demonstrated robust clinical efficacy in terms of improvment hemodynamic parameters, exercise capacity and patients' quality of life is the stimulator of the soluble guanylate cyclase riociguat. The efficacy and safety of riociguat have been investigated in short-term and long-term studies with follow-up up to 6 years. Results of these studies have constituted the basis forits approval by the regulatory authorities of more than 50 countries for the treatment of inoperable CTEPH and persistent or recurrent CTEPH after pulmonary thromboendarterectomy. In the European Union, USA and many other countries, riociguat is the only pharmacological agent approved for these indications.

Chronic Thromboembolic Pulmonary Hypertension and Antiphospholipid Syndrome with Immune Thrombocytopenia: A Case Report

BACKGROUND Antiphospholipid syndrome is an autoimmune disorder characterized by a hypercoagulable state associated with circulating antiphospholipid antibodies. The presence of antiphospholipid antibodies can result in a variety of clinical symptoms, such as thrombocytopenia, stillbirth, endocardial pathologies, and recurrent pulmonary embolism. CASE REPORT We present the case of a 23-year-old man with antiphospholipid syndrome and chronic thromboembolic pulmonary hypertension who developed severe thrombocytopenia. The patient died from right heart failure before the thrombocytopenia could be managed, preventing performance of a pulmonary endarterectomy procedure. CONCLUSIONS Managing platelet counts in patients with antiphospholipid syndrome prior to major surgery is very problematic, and requires similar treatment strategy as in patients with immune thrombocytic thrombocytopenia. Platelet transfusions may further decrease platelet count, as it can trigger formation of new antibodies.

Chronic Thromboembolic Pulmonary Hypertension: Epidemiology, Diagnosis, and Management

Chronic thromboembolic pulmonary hypertension (CTEPH), classified as World Health Organization (WHO) group 4 pulmonary hypertension (PH), is an interesting and rare pulmonary vascular disorder secondary to mechanical obstruction of the pulmonary vasculature from thromboembolism resulting in PH. The pathophysiology is complex, beginning with mechanical obstruction of the pulmonary arteries, which eventually leads to arteriopathic changes and vascular remodeling in the nonoccluded arteries and in the distal segments of the occluded arteries mediated by thrombus nonresolution, abnormal angiogenesis, endothelial dysfunction, and various local growth factors. Based on available data, CTEPH is a rare disease entity occurring in a small proportion (0.5-3%) of patients after acute pulmonary embolism with an annual incidence ranging anywhere between 1 and 7 cases per million population. It is often underdiagnosed or misdiagnosed as idiopathic pulmonary arterial hypertension due to a lack of clinical suspicion or the under-utilization of radionuclide ventilation/perfusion scan. Although the current standard remains planar ventilation/perfusion scintigraphy as the initial imaging study to screen for CTEPH, and invasive pulmonary angiography with right heart catheterization as confirmatory modalities, they are likely to be replaced by modalities that can provide both anatomic and functional data while minimizing radiation exposure. Surgery is the gold standard treatment and offers better improvements in clinical and hemodynamic parameters compared with medical therapy. The management of CTEPH requires a multidisciplinary team, operability assessment, experienced surgical center, and the consideration of medical PH-directed therapies in patients who have inoperable disease, in addition to supportive therapies. Although, balloon pulmonary angioplasty is gaining interest to improve pulmonary hemodynamics and symptoms in CTEPH patients not amenable to surgery, further investigative randomized studies are needed to validate its use. It is very important for the present-day physician to be familiar with the disease entity and its appropriate evaluation to facilitate early diagnosis and appropriate management.

Health-related quality of life, treatment adherence and psychosocial support in patients with pulmonary arterial hypertension or chronic thromboembolic pulmonary hypertension

Pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTEPH) share similar quality of life impairment. The aim of the present study was to investigate health-related quality of life (HRQoL) and its relation to the perception of treatment and psychosocial support among PAH and CTEPH patients. All adult PAH or CTEPH patients in the Swedish Pulmonary Arterial Hypertension Register were invited to participate in a national cohort survey. The survey included the EuroQol 5-dimensions (EQ-5D) instrument that measures an individual’s HRQoL; the Beliefs about Medicines Questionnaire-Specific Scale that assesses the perception of PAH-specific treatment; the Mastery scale that evaluates the feeling of control and ability to cope with the disease; and the Social Network and Support Scale that maps the social support network. Of the 440 invited patients, 74% responded. Mean age was 66 ± 14 years, 58% were female and 69% diagnosed with PAH. Patients with PAH were younger, more often female and had a lower EQ-5D index (0.67 ± 0.29 vs. 0.73 ± 0.25, p = 0.050) than patients with CTEPH. Patients with a low EQ-5D index had more concerns about treatment (p = 0.004), lower coping ability (p < 0.001), less emotional support (p = 0.003) and less accessible social network (p = 0.002). In conclusion, patients with an impaired HRQoL also reported negative effects on their social support network, ability to handle stressors and concerns about treatment.

Chronic thromboembolic pulmonary hypertension from the perspective of patients with pulmonary embolism

Chronic thromboembolic pulmonary hypertension (CTEPH) is a rare but feared long-term complication of acute pulmonary embolism (PE), although CTEPH may occur in patients with no history of symptomatic venous thromboembolism. It represents the most severe presentation of the so-called 'post-PE syndrome', a phenomenon of permanent functional limitations after PE caused by deconditioning after PE or ventilatory or circulatory impairment as a result of unresolved pulmonary artery thrombi. Because the post-PE syndrome may occur in up to 50% of PE survivors, and CTEPH tends to have an insidious and non-specific clinical presentation, CTEPH is often not diagnosed or diagnosed after a very long delay. Once the diagnosis is confirmed, the treatment of choice is pulmonary endarterectomy which effectively lowers the pulmonary vascular resistance and normalizes resting pulmonary artery pressures, leading to recovery of the right ventricle. When pulmonary endarterectomy is not technically feasible, balloon pulmonary angioplasty may be a potential acceptable alternative. Also, medical treatment may help to improve patient's symptoms and hemodynamics. Current studies are focusing on strategies for earlier CTEPH diagnosis after acute PE, as well as the most optimal treatment of inoperable patients. This review will focus on the epidemiology, risk factors, diagnosis and treatment of CTEPH from the perspective of the PE patient.

Characteristics and survival data from Latvian pulmonary hypertension registry: comparison of prospective pulmonary hypertension registries in Europe

Patient registries are a valuable tool in the research of rare conditions such as pulmonary hypertension (PH). We report comprehensive hemodynamic and survival data of 174 patients with pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTEPH), included in the prospective Latvian PH registry over a period of > 9 years. In total, 130 adult PAH patients (75%) and 44 adult CTEPH patients (25%) were enrolled. The median follow-up period was 33 months for PAH and 18 months for CTEPH, P = 0.001. Latvian CTEPH patients had significantly higher plasma levels of B-type natriuretic peptide, higher pulmonary vascular resistance, and lower cardiac index than Latvian PAH patients. Calculated incidence of PAH and CTEPH in Latvia in 2016 was 13.7 and 5.1 cases per million inhabitants, calculated prevalence was 45.7 and 15.7 cases per million inhabitants, respectively. Survival rates at one, three, and five years for PAH patients was 88.0%, 73.3%, and 58.1%, and 83.8%, 59.0%, and 44.2% for CTEPH patients, respectively. We compared our study results with data from European adult PH registries. Latvian PAH patients had the fourth lowest and CTEPH patients the lowest one-year survival rate among European adult PH registries. As most PH registries in Europe are small, yet with equivalent patient inclusion criteria, it would be desirable to combine these registries to produce more reliable and high-quality study results.

Determinants of Health-Related Quality of Life 1 Year after Pulmonary Thromboendarterectomy

BACKGROUND

Pulmonary thromboendarterectomy (PTE) is a recognized treatment for patients with chronic thromboembolic pulmonary hypertension (CTEPH), with good long-term hemodynamic results. The aim of this study was to test the hypothesis that the dynamics of health-related quality of life (QoL), 1 year after PTE, depend both on the clinical determinants associated with the underlying disease and the adverse events occurring in the early postoperative period.

METHODS

This prospective cohort study included 136 patients with CTEPH. All patients before and after PTE (1-year follow-up) were examined in terms of QoL, by using the Short Form 36 Health Survey Questionnaire.

RESULTS

One year after PTE, a significant improvement in the QoL of patients was observed in all subscales of the Short Form 36 Health Survey Questionnaire, except in the general health scale. Multivariate analysis showed that the predictors adversely affecting the dynamics of QoL after PTE were the presence of comorbidities (such as chronic obstructive pulmonary disease [COPD] and coronary artery disease) and early postoperative complications (specific ones for this category of patients are residual pulmonary hypertension and neurological complications, and nonspecific ones are atrial fibrillation and heart failure).

CONCLUSIONS

The determinants that affect the dynamics of QoL 1 year after PTE in patients with CTEPH were the presence of comorbidities (COPD and coronary artery disease) and adverse events in the early postoperative period (residual pulmonary hypertension, neurological complications, atrial fibrillation, and heart failure).

Chronic obstructive pulmonary disease in patients with chronic thromboembolic pulmonary hypertension: Prevalence and implications for surgical treatment outcome

OBJECTIVE

The aim of our study was to investigate the prevalence of chronic obstructive pulmonary disease (COPD) in patients with chronic thromboembolic pulmonary hypertension (CTEPH) and examine their impact on the results of pulmonary thrombendarterectomy (PEA).

METHODS

We enrolled 136 patients with CTEPH who scheduled for elective PEA. Pulmonary function tests (PFTs) including full-body plethysmography with bronchodilation test and lung diffusion capacity assessment were performed in all patients prior to surgery treatment. The diagnosis of COPD was verified in accordance with the recommendations of the Global Initiative for Chronic Obstructive Lung Disease 2017. The effect of COPD on perioperative characteristics, complications, in-hospital and one-year mortality of patients with CTEPH were analysed.

RESULTS

In the study group with CTEPH the prevalence of COPD was 23%. In 13% of patients, COPD was first detected. The results of PFTs showed more severe airflow limitations with obstructive pattern in patients with concomitant COPD, as well as a more pronounced decrease in the lung diffusion capacity. The presence of COPD in patients with CTEPH significantly increases the risk of residual pulmonary hypertension in the early postoperative period of PEA (OR = 6.2 (1.90-10.27), P = .002), duration of hospital stay (OR = 1.1 (1.01-1.20), P = .020) and the risk of in-hospital mortality (OR = 4.4 (1.21-16.19), P = .023). The lung diffusion capacity revealed significant negative associations with the duration of hospital stay and in-hospital mortality (OR 0.87 (0.74-0.98), P = .012).

CONCLUSION

COPD in patients with CTEPH significantly increases the risk of residual pulmonary hypertension, in-hospital mortality and increases the duration of hospital stay after PEA.

Lung Ischaemia-Reperfusion Injury: The Role of Reactive Oxygen Species

Lung ischaemia-reperfusion injury (LIRI) occurs in many lung diseases and during surgical procedures such as lung transplantation. The re-establishment of blood flow and oxygen delivery into the previously ischaemic lung exacerbates the ischaemic injury and leads to increased microvascular permeability and pulmonary vascular resistance as well as to vigorous activation of the immune response. These events initiate the irreversible damage of the lung with subsequent oedema formation that can result in systemic hypoxaemia and multi-organ failure. Alterations in the production of reactive oxygen species (ROS) and reactive nitrogen species (RNS) have been suggested as crucial mediators of such responses during ischaemia-reperfusion in the lung. Among numerous potential sources of ROS/RNS within cells, nicotinamide adenine dinucleotide phosphate (NADPH) oxidases, xanthine oxidases, nitric oxide synthases and mitochondria have been investigated during LIRI. Against this background, we aim to review here the extensive literature about the ROS-mediated cellular signalling during LIRI, as well as the effectiveness of antioxidants as treatment option for LIRI.

Prevention and treatment of the chronic thromboembolic pulmonary hypertension

Chronic thromboembolic pulmonary hypertension (CTEPH) is an uncommon and late complication of pulmonary embolism resulting from misguided remodelling of residual pulmonary thromboembolic material and small-vessel arteriopathy. CTEPH is the only form of pulmonary hypertension (PH) potentially curable by pulmonary endarterectomy (PEA). Unfortunately, several patients have either an unacceptable risk-benefit ratio for undergoing the surgical intervention or develop persistent PH after PEA. Novel medical and endovascular therapies can be considered for them. The soluble guanylate cyclase stimulator riociguat is recommended for the treatment of patients with inoperable disease or with recurrent/persistent PH after PEA. Other drugs developed for the treatment of other forms of PH, as prostanoids, phosphodiesterase-5 inhibitors and endothelin receptor antagonists have been used in the treatment of CTEPH, with limited benefit. Balloon pulmonary angioplasty is a novel and promising technique and is progressively emerging from the pioneering phase. Highly specialized training level and complex protocols of postoperative care are mandatory to consolidate the technical success of the surgical and endovascular intervention.

Two-stage Treatment Using Balloon Pulmonary Angioplasty and Pulmonary Endarterectomy in a Patient with Chronic Thromboembolic Pulmonary Hypertension

We performed a 2-stage procedure combining balloon pulmonary angioplasty and pulmonary endarterectomy for a high-risk chronic thromboembolic pulmonary hypertension patient with high pulmonary vascular resistance. First, balloon pulmonary angioplasty was performed for distal lesions to improve hemodynamics and decrease the surgical risk. Subsequently, pulmonary endarterectomy was performed for proximal lesions, and the hemodynamics and symptoms improved dramatically. Our strategy was therefore found to be useful for treating a high-risk chronic thromboembolic pulmonary hypertension patient.

Real-World Switching to Riociguat: Management and Practicalities in Patients with PAH and CTEPH

Purpose

A proportion of patients with pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTEPH) do not achieve treatment goals or experience side effects on their current therapy. In such cases, switching patients to a new drug while discontinuing the first may be a viable and appropriate treatment option. CAPTURE was designed to investigate how physicians manage the switching of patients to riociguat in real-world clinical practice. Observations from the study were used to assess whether recommendations in the riociguat prescribing information are reflected in clinical practice.

Methods

CAPTURE was an international, multicenter, uncontrolled, retrospective chart review that collected data from patients with PAH or inoperable or persistent/recurrent CTEPH who switched to riociguat from another pulmonary hypertension (PH)-targeted medical therapy. The primary objective of the study was to understand the procedure undertaken in real-world clinical practice for patients switching to riociguat.

Results

Of 127 patients screened, 125 were enrolled in CAPTURE. The majority of patients switched from a phosphodiesterase type 5 inhibitor (PDE5i) to riociguat and the most common reason for switching was lack of efficacy. Physicians were already using the recommended treatment-free period when switching patients to riociguat from sildenafil, but a slightly longer period than recommended for tadalafil. In line with the contraindication, the majority of patients did not receive riociguat and PDE5i therapy concomitantly. Physicians also followed the recommended dose-adjustment procedure for riociguat.

Conclusion

Switching to riociguat from another PH-targeted therapy may be feasible in real-world clinical practice in the context of the current recommendations.

Electronic supplementary material

The online version of this article (10.1007/s00408-018-0100-3) contains supplementary material, which is available to authorized users.

Overexpression of microRNA-506-3p aggravates the injury of vascular endothelial cells in patients with hypertension by downregulating Beclin1 expression

The aim of the present study was to measure the expression of microRNA (miRNA)-506-3p in the peripheral blood of patients with hypertension and to determine the biological functions and mechanisms of action of miR-506-3p. A total of 61 patients with primary hypertension were included in the present study. Peripheral blood was collected from all patients, as well as 31 healthy subjects who were included in a control group. The expression of miR-506-3p in peripheral blood was determined by reverse transcription-quantitative polymerase chain reaction. Human umbilical vein endothelial cells (HUVECs) were transfected with miR-506-3p mimics or miR-506-3p inhibitor. The proliferation and migration of HUVECs were determined using cell-counting kit 8 and Transwell assays, respectively. The cell cycle and apoptosis of HUVECs were detected by flow cytometry. The expression of Beclin1 (BECN1) protein, a potential target of miR-506-3p, was measured using western blotting. A dual-luciferase reporter assay was performed to determine the interaction between BECN1 and miR-506-3p. It was demonstrated that miR-506-3p expression in the peripheral blood of patients with patients was upregulated and dependent on the severity of hypertension. miR-506-3p overexpression inhibited the proliferation and migration of HUVECs. In addition, miR-506-3p inhibited the transition from the G1 phase to the S-phase in HUVECs. Overexpression of miR-506-3p promoted the apoptosis of HUVECs. Notably, miR-506-3p downregulated the expression of BECN1 by directly binding to its 3′-untranslated region. The present study demonstrated that miR-506-3p expression is elevated in the peripheral blood of patients with hypertension and is associated with the severity of hypertension. By downregulating BECN1 expression, miR-506-3p aggravates injury in vascular endothelial cells by inhibiting the proliferation and migration of HUVECs, as well as promoting their apoptosis.

Riociguat in patients with chronic thromboembolic pulmonary hypertension: results from an early access study

Background

Following positive results from the Phase III CHEST-1 study in patients with inoperable or persistent/recurrent chronic thromboembolic pulmonary hypertension (CTEPH), the Phase IIIb CTEPH early access study (EAS) was designed to assess the safety and tolerability of riociguat in real-world clinical practice, as well as to provide patients with early access to riociguat before launch. Riociguat is approved for the treatment of inoperable and persistent/recurrent CTEPH.

Methods

We performed an open-label, uncontrolled, single-arm, early access study in which 300 adult patients with inoperable or persistent/recurrent CTEPH received riociguat adjusted from 1 mg three times daily (tid) to a maximum of 2.5 mg tid. Patients switching from unsatisfactory prior pulmonary arterial hypertension (PAH)-targeted therapy (n = 84) underwent a washout period of at least 3 days before initiating riociguat. The primary aim was to assess the safety and tolerability of riociguat, with World Health Organization functional class and 6-min walking distance (6MWD) as exploratory efficacy endpoints.

Results

In total, 262 patients (87%) completed study treatment and entered the safety follow-up (median treatment duration 47 weeks). Adverse events were reported in 273 patients (91%). The most frequently reported serious adverse events were syncope (6%), right ventricular failure (3%), and pneumonia (2%). There were five deaths, none of which was considered related to study medication. The safety and tolerability of riociguat was similar in patients switched from other PAH-targeted therapies and those who were treatment naïve. In patients with data available, mean ± standard deviation 6MWD had increased by 33 ± 42 m at Week 12 with no clinically relevant differences between the switched and treatment-naïve subgroups.

Conclusions

Riociguat was well tolerated in patients with CTEPH who were treatment naïve, and in those who were switched from other PAH-targeted therapies. No new safety signals were observed.

Trial registration

ClinicalTrials.org NCT01784562. Registered February 4, 2013.

Electronic supplementary material

The online version of this article (10.1186/s12890-017-0563-7) contains supplementary material, which is available to authorized users.

The changing landscape of chronic thromboembolic pulmonary hypertension management

For patients with chronic thromboembolic pulmonary hypertension (CTEPH), the current standard of care involves surgical removal of fibro-thrombotic obstructions by pulmonary endarterectomy. While this approach has excellent outcomes, significant proportions of patients are not eligible for surgery or suffer from persistent/recurrent pulmonary hypertension after the procedure. The availability of balloon pulmonary angioplasty and the approval of the first medical therapy for use in CTEPH have significantly improved the outlook for patients ineligible for pulmonary endarterectomy. In this comprehensive review, we discuss the latest developments in the rapidly evolving field of CTEPH. These include improvements in imaging modalities and advances in surgical and interventional techniques, which have broadened the range of patients who may benefit from such procedures. The efficacy and safety of targeted medical therapies in CTEPH patients are also discussed, particularly the encouraging data from the recent MERIT-1 trial, which demonstrated the beneficial impact of using macitentan to treat patients with inoperable CTEPH, including those on background therapy. As the treatment options for CTEPH improve, hybrid management involving more than one intervention in the same patient may become a viable option in the near future.

Management of CTEPH is evolving rapidly, leading to improved patient outcomeshttp://ow.ly/rHrt30gUQWX

Cardiopulmonary bypass does not induce lung dysfunction after pulmonary thrombarterectomy: role of pulmonary compliance

OBJECTIVES

Pulmonary endarterectomy is a heavy surgical procedure that is performed under cardiopulmonary bypass (CPB) and aimed to cure postembolic pulmonary hypertension. Reperfusion oedema is both the hallmark of successful surgical procedure and the most frequent postoperative complication. Post-CPB lung dysfunction was not mentioned in any report. We undertook a study to determine whether post-CPB lung dysfunction was present in these patients.

METHODS

In a retrospective cohort study with matching on some baseline covariates, we selected 41 patients who had undergone pulmonary endarterectomy and in whom pre-, intra- and postoperative records were complete. The control group was composed of 39 patients operated on from elective cardiac surgery during the same period and matched with a study group for age, gender, body mass index, blood creatinine, diabetes and baseline partial pressure of oxygen/fraction of inspired oxygen ratio. Criteria for post-CPB lung dysfunction were partial pressure of oxygen/fraction of inspired oxygen ratio decrease and bilateral basal oedema. Explanatory variables for post-CPB lung dysfunction were coronary arterial bypass, pleura opening, static pulmonary compliance measured at the time of thorax closed then retracted, fluid infusion, transfusion and vasopressors.

RESULTS

All patients operated on from pulmonary endarterectomy presented radiological oedema reperfusion in surgical unblocking areas. Among them, only 2 had bilateral basal oedema when compared to the 24 patients from the control group (P < 0.001). Partial pressure of oxygen/fraction of inspired oxygen ratio increased in the study group and decreased in the control group (30 ± 109 vs -67 ± 134 mmHg, P < 0.001). Control group patients with high-baseline pulmonary compliance were at risk for post-CPB lung dysfunction.

CONCLUSIONS

Patients operated on from pulmonary endarterectomy were saved from post-CPB lung dysfunction. The latter could be induced by a mechanical phenomenon.

Reoperative Pulmonary Endarterectomy: Past Failures of Patient Selection Can Assist in Future Practice of Informed Consent

The Pavia group reports their experience with reoperative pulmonary endarterectomy for patients with chronic thromboembolic pulmonary hypertension. They achieved impressive results in terms of hemodynamic parameters and functional status; however, a mortality rate of 40% represents inappropriate patient selection. Recommendations are made for identifying ideal operative candidates.

Imaging in Chronic Thromboembolic Pulmonary Hypertension

Chronic thromboembolic pulmonary hypertension (CTEPH) is one of the potentially curable causes of pulmonary hypertension and is definitively treated with pulmonary thromboendartectomy. CTEPH can be overlooked, as its symptoms are nonspecific and can be mimicked by a wide range of diseases that can cause pulmonary hypertension. Early diagnosis of CTEPH and prompt evaluation for surgical candidacy are paramount factors in determining future outcomes. Imaging plays a central role in the diagnosis of CTEPH and patient selection for pulmonary thromboendartectomy and balloon pulmonary angioplasty. Currently, various imaging tools are used in concert, with techniques such as computed tomography (CT) and conventional pulmonary angiography providing detailed structural information, tests such as ventilation-perfusion (V/Q) scanning providing functional data, and magnetic resonance imaging providing a combination of morphologic and functional information. Emerging techniques such as dual-energy CT and single photon emission computed tomography-CT V/Q scanning promise to provide both anatomic and functional information in a single test and may change the way we image these patients in the near future. In this review, we discuss the roles of various imaging techniques and discuss their merits, limitations, and relative strengths in depicting the structural and functional changes of CTEPH. We also explore newer imaging techniques and the potential value they may offer.

Molecular mechanisms in vascular injury induced by hypertension: Expression and role of microRNA-34a

The aim of the present study was to investigate the expression and function of microRNA (miR)-34a in patients with primary hypertension. The expression of miR-34a was measured in the peripheral blood of 50 patients with primary hypertension and 28 normal controls by reverse transcription quantitative polymerase chain reaction. In addition, human umbilical vein endothelial cells (HUVECs) were transfected with an miR-34a inhibitor to suppress the expression of miR-34a, and the proliferation, migration and cell cycle distribution of HUVECs were measured by Cell Counting Kit-8, Transwell and flow cytometry assays. The target of miR-34a was also predicted by bioinformatics analysis and verified by a dual-luciferase reporter gene assay and western blot analysis. miR-34a was significantly upregulated in the peripheral blood of patients with hypertension when compared with controls (P<0.05), and upregulation of miR-34a was associated with a higher clinical stage of hypertension (phase III; P<0.05). In vitro experiments demonstrated that inhibition of miR-34a promoted the proliferation, migration and G1/S transition of HUVECs, relative to scramble-miR controls (P<0.05). Furthermore, transforming growth factor β-induced factor homeobox 2 (TIGF2) was predicted and verified to be a direct target of miR-34a. Collectively, these data suggested that miR-34a was upregulated in the peripheral blood of patients with hypertension, and that upregulated miR-34a may promote vascular endothelial injury by targeting TIGF2.

Long-term outcomes of surgery for chronic thromboembolic pulmonary hypertension compared with medical therapy at a single Korean center

BACKGROUND/AIMS

Pulmonary endarterectomy (PEA) is the gold standard for treating chronic thromboembolic pulmonary hypertension (CTEPH) in Western countries. The aim of this study was to investigate the long-term outcomes of performing PEA on CTEPH patients in comparison with medical therapy at a single Korean center.

METHODS

This retrospective study included 88 CTEPH patients. These patients were classified into the PEA group (n = 37) or non-PEA group (i.e., medical therapy; n = 51). The clinical characteristics, hemodynamic data, and long-term survival rates were compared. Independent prognostic factors for CTEPH were also investigated.

RESULTS

CTEPH was not associated with either gender, and the mean age at diagnosis was 53.3 ± 13.7 years. Echocardiography revealed that the mean peak velocity of the tricuspid regurgitation jet was 4.2 ± 0.7 m/sec and the mean pulmonary arterial pressure was 51.7 ± 15.1 mmHg. The PEA and non-PEA groups demonstrated no significant differences, except in terms of the right ventricular end-diastolic diameter. The survival rates of the PEA group were significantly higher than the non-PEA group at 1, 3, 5, and 10 years (p = 0.032). Multivariate analyses indicated that World Health Organization class IV and PEA were significant predictors of poorer and better outcomes, respectively.

CONCLUSIONS

PEA demonstrates more favorable effects on long-term survival than medical therapy in Korean CTEPH patients who were considered operable.

Chronic complications of venous thromboembolism

Venous thromboembolism (VTE) is a common disease (~700 per 100 000) that is associated with significant risk of recurrence, chronic complications, and substantial mortality, with reported death rates of up to 40% at 10 years. The development of novel anticoagulants has revolutionized the treatment of acute VTE, while strategies for prevention and treatment of chronic complications still seek for such a landmark change. Impaired thrombus resolution is the common denominator behind VTE complications, which are postthrombotic syndrome (PTS) and chronic thromboembolic pulmonary hypertension (CTEPH). PTS and CTEPH are associated with substantial morbidity and high healthcare expenses. While PTS occurs in up to 50% of patients after symptomatic deep vein thrombosis, only a small and poorly defined number of patients are diagnosed with CTEPH after pulmonary embolism. This review is a comprehensive summary of VTE-related chronic complications, their epidemiology, diagnosis, and treatment.

Pulmonary endarterectomy in chronic thromboembolic pulmonary hypertension

BACKGROUND

Management and outcome of patients with operable chronic thromboembolic pulmonary hypertension (CTEPH) who underwent pulmonary endarterectomy (PEA) at a large German referral center were investigated.

METHODS

In Germany, 394 PEAs were performed in 2014 and 2015 with an in-hospital mortality rate of 5.8%. Of these, 253 patients (64.2%) were treated at the Kerckhoff Clinic, Bad Nauheim, and 237 (93.7%; median age, 62 years [interquartile range [IQR], 52-72 years]; 46.0% female) were included in the present analysis.

RESULTS

On referral, 52 patients (22.0%) were treated with pulmonary arterial hypertension-specific drugs and 95 (40.4%) were treated with non-vitamin K-dependent oral anticoagulants, and 14 (5.9%) had mean pulmonary artery pressure <25 mm Hg and were classified as having chronic thromboembolic pulmonary vascular disease. PEA was feasible in 236 (99.6%) patients with median duration of surgery of 397 minutes (IQR, 363-431 minutes). Periprocedural (0%) and in-hospital (2.5%) mortality rates were very low. Forty-two patients (17.7%) had intraoperative complications, and 60 (25.3%) had post-operative complications. The duration of surgery was the only predictor of in-hospital mortality (≥500 minutes; odds ratio [OR], 32.0; 95% confidence interval [CI], 5.5-187.6) and the only independent predictor of intraoperative (≥440 minutes; OR, 10.8; 95% CI, 4.4-26.5) and post-operative (≥390 minutes; OR, 2.4; 95%CI, 1.1-5.7) complications. Only intraoperative complications independently predicted a longer duration of surgery (≥397 minutes; OR, 5.0; 95% CI, 2.2-11.2).

CONCLUSIONS

In an experienced center with multidisciplinary diagnostic and therapeutic approaches, PEA is safe. Prognosis was mainly determined by occurrence of intraoperative complications and duration of surgery rather than patients' pre-operative status.