Pulmonary Thromboendarterectomy for Chronic Thromboembolic Pulmonary Hypertension : A Systematic Review

A systematic review of the impact of pulmonary thromboendarterectomy on health-related quality of life

Pulmonary thromboendarterectomy (PTE) is the current gold standard treatment for chronic thromboembolic pulmonary hypertension (CTEPH) and is a viable treatment option for chronic thromboembolic pulmonary disease (CTEPD). The progressive nature of both diseases severely impacts health-related quality of life (HRQoL) across a variety of domains. This systematic review was performed to evaluate the impact of PTE on short- and long-term HRQoL. A literature search was conducted on PubMed for studies matching the eligibility criteria between January 2000 and September 2022. OVID (MEDLINE), Google Scholar, EBSCOhost (EMBASE), and bibliographies of included studies were reviewed. Inclusion of studies was based on predetermined eligibility criteria. Quality appraisal and data tabulation were performed using predetermined forms. Results were synthesized by narrative review. The structure of this systematic review follows the PRISMA guidelines. This systematic review was prospectively registered in the PROSPERO register (CRD42022342144). Thirteen studies (2184 patients) were included. Within 3 months post-PTE, HRQoL improved in both CTEPD and CTEPH as measured by disease-specific and generic questionnaires. HRQoL improvements were sustained up to 5 years postoperatively in patients with CTEPH post-PTE. PTE remains the gold standard for treating CTEPH and improving HRQoL. Residual pulmonary hypertension and comorbidities such as COPD and coronary artery disease decrement HRQoL over time. The impact of mPAP and PVR on HRQoL outcomes postoperatively remain ambiguous. Pulmonary thromboendarterectomy remains the gold standard for treating CTEPH and has shown to improve HRQoL outcomes at 3-month sustaining improvements up to 5-year postoperatively. Residual pulmonary hypertension and comorbidities hinder HRQoL outcomes post-PTE.

Acute Kidney Injury After Pulmonary Thromboendarterectomy: Associated Factors and Impact

BACKGROUND

Acute kidney injury (AKI) is a common complication after pulmonary thromboendarterectomy (PTE) that has been shown to be associated with worse outcomes. Our study assesses factors associated with the development of postoperative AKI after PTE and its impact on clinical outcomes.

METHODS

We retrospectively analyzed 247 patients who underwent PTE at our institution between June 2009 and December 2020. Baseline characteristics, risk factors, and outcomes were compared between patients with and without postoperative AKI. The primary endpoint was development of postoperative AKI using the Kidney Disease Improving Global Outcomes definition, and secondary endpoints were length of hospital stay, hospital mortality, and 5-year mortality.

RESULTS

The overall incidence of postoperative AKI in our study population was 49%. One hundred twenty-three patients (50.8%) did not develop AKI postoperatively, 87 patients (35.9%) developed stage 1 AKI postoperatively, 21 patients (8.7%) developed stage 2 AKI postoperatively, and 11 (4.5%) developed stage 3 AKI postoperatively. Patients who developed AKI postoperatively had longer hospital stays, higher in-hospital mortality rates, and higher 5-year mortality rates than patients who did not develop postoperative AKI. Higher body mass index, older age, low preoperative hemoglobin, low ejection fraction, and low creatinine were shown to be associated with postoperative AKI development.

CONCLUSIONS

Patients who developed AKI after PTE had worse mortality and morbidity. Clinicians should have a lower threshold for suspecting AKI and consider implementing Kidney Disease Improving Global Outcomes-based AKI prevention bundles for patients with factors associated with development of AKI.

Single-Center Experience of Pulmonary Endarterectomy for Chronic Thromboembolic Pulmonary Hypertension: The Results from the Tabriz University Medical Sciences (TUMS) CTEPH Program

INTRODUCTION

Pulmonary endarterectomy (PEA) remains the preferred and potentially curative option for patients with chronic thromboembolic pulmonary hypertension (CTEPH). This study aimed to report the results of PEA for CTEPH in a tertiary center in Tabriz, Iran.

METHODS

We analyzed the results of 42 CTEPH patients undergoing PEA, who were enrolled in the Tabriz University of Medical Sciences (TUMS-CTEPH) from January 2016 to October 2020. The main outcome measures included the New York Heart Association (NYHA) functional classification, the 6-Minute Walk Distance, hemodynamic measures in right heart catheterization, morbidity, and mortality.

RESULTS

There was a significant improvement in the NYHA function class (2.6 ± 0.5 vs 1.1 ± 0.34), mean pulmonary arterial pressure (47.1 ± 13 vs 27.9 ± 8 mm Hg), cardiac output (4.3 ± 1.06 vs 5.9 ± 1.2 L/min), and pulmonary vascular resistance (709.4 ± 297.5 vs 214 ± 77 dyn s/cm5). Fifteen patients (35%) developed complications. The most common complication (10 [23%]) was reperfusion injury. Also, postsurgical mortality was 4% during hospital admission and 1-year follow-up.

CONCLUSION

This is the first single-center report of PEA from Iran. Post-PEA and 1-year survival were acceptable as a referral center. PEA can be performed safe with low mortality. Greater awareness of PEA and patients' access to experienced CTEPH centers are important issues.

Role of Physical Therapists in the Management of Individuals at Risk for or Diagnosed With Venous Thromboembolism: Evidence-Based Clinical Practice Guideline 2022

No matter the practice setting, physical therapists work with patients who are at risk for or who have a history of venous thromboembolism (VTE). In 2016, the first clinical practice guideline (CPG) addressing the physical therapist management of VTE was published with support by the American Physical Therapy Association's Academy of Cardiovascular and Pulmonary Physical Therapy and Academy of Acute Care, with a primary focus on lower extremity deep vein thrombosis (DVT). This CPG is an update of the 2016 CPG and contains the most current evidence available for the management of patients with lower extremity DVT and new key action statements (KAS), including guidance on upper extremity DVT, pulmonary embolism, and special populations. This document will guide physical therapist practice in the prevention of and screening for VTE and in the management of patients who are at risk for or who have been diagnosed with VTE. Through a systematic review of published studies and a structured appraisal process, KAS were written to guide the physical therapist. The evidence supporting each action was rated, and the strength of statement was determined. Clinical practice algorithms based on the KAS were developed that can assist with clinical decision-making. Physical therapists, along with other members of the health care team, should implement these KAS to decrease the incidence of VTE, improve the diagnosis and acute management of VTE, and reduce the long-term complications of VTE.

Pulmonary thromboendarterectomy for chronic thromboembolic pulmonary hypertension: a systematic review

BACKGROUND

Pulmonary thromboendarterectomy (PTE) is the gold standard treatment for patients with chronic thromboembolic pulmonary hypertension (CTEPH). However, the results are poorly quantified outside a few registry reports and several individual centers.

METHODS

A systematic review was performed searching five electronic databases assessing the outcomes for adult patients undergoing PTE for CTEPH. All articles that reported mortality data were included. Primary outcome measures were early/inpatient mortality; secondary outcomes were survival, pulmonary haemodynamics, morbidity and functional status following PTE for CTEPH. Results were pooled via a meta-analysis of proportions and meta-regression.

RESULTS

A total of 5,717 studies were identified, yielding sixty-one relevant papers. Thirty-day mortality ranged from 0.8% to 24.4%, and on meta-analysis was 8.4% [95% confidence interval (CI): 7.2-9.6%]. Mortality was noted to decrease with increasing center volume of PTE cases (P<0.01). Residual pulmonary hypertension was reported in 8.2% to 44.5% of patients.

CONCLUSIONS

CTEPH is associated with acceptable short-term mortality and an improvement in pulmonary hemodynamics. With increasing volume of experience and ongoing developments over time peri-operative mortality continues to decrease.

Pulmonary thromboendarterectomy in chronic thromboembolic pulmonary hypertension: the Spanish experience

BACKGROUND

Chronic thromboembolic pulmonary hypertension (CTEPH) can be cured by pulmonary endarterectomy (PEA). It is considered the best and only curable treatment option for patients with accessible lesions evaluated as optimal candidates. We describe the experience of the two reference centers in Spain, in order to reinforce the need for referring CTEPH patients to a specialized center to be assessed by a Multidisciplinary Expert Team.

METHODS

We included a population of 338 patients who met the definition for CTEPH and underwent PEA between January 2007 and December 2019. The surgery was indicated in almost 60% of patients assessed. Demographic, anthropometric, hemodynamic and echocardiographic features are listed for PEA patients. Immediate and one-year postoperative outcomes as well as overall mortality were analyzed.

RESULTS

Mean age was 53.5±15.0 years, 53.8% were men; a total of 68.5% were in WHO functional class III-IV; and most of them were in a preoperative hemodynamic condition: mean pulmonary arterial pressure (mPAP) was 46.5±13.1 mmHg and mean pulmonary vascular resistance (PVR) was 764.5±392.8 dyn·s·cm-5. PEA surgery was performed with cardiopulmonary bypass (CBP) and circulatory arrest, with very few complications [including neurological, postoperative reperfusion edema, extracorporeal membrane oxygenation (ECMO) implant and cardiac failure] and optimal postoperative results, where exercise capacity increased and mPAP and PVR values decreased significantly. Presence of persistent pulmonary hypertension (PH) at the six-month right heart catheterization was evaluated. A 3.3% perioperative mortality was achieved. Overall, one-, three- and five-year survival rates were analyzed by Kaplan-Meier's method (94.8%, 93.3% and 90.5% respectively), as well as for residual PH patients. Mortality risk factors were assessed.

CONCLUSIONS

Outstanding PEA results were seen in the immediate, one-year and long-term outcomes. The incidence of complications, including in-hospital mortality and long-term mortality were also below European rates.

Selexipag for the treatment of chronic thromboembolic pulmonary hypertension

Treatment options for inoperable chronic thromboembolic pulmonary hypertension (CTEPH) remain limited. Selexipag, an oral selective IP prostacyclin-receptor agonist approved for pulmonary arterial hypertension, is a potential treatment option for CTEPH.In this multicentre, randomised, double-blind, placebo-controlled study, 78 Japanese patients with inoperable CTEPH or persistent/recurrent pulmonary hypertension after pulmonary endarterectomy and/or balloon pulmonary angioplasty were randomly assigned to receive placebo or selexipag. The primary endpoint was the change in pulmonary vascular resistance (PVR) from baseline to week 20. The secondary endpoints were changes in other haemodynamic parameters, 6-min walk distance (6 WMD), Borg Dyspnoea Scale score, World Health Organisation (WHO) functional class, EuroQol 5 dimensions 5-level and N-terminal pro-brain natriuretic peptide.The change in PVR was -98.2±111.3 dyn·s·cm^-5 and -4.6±163.6 dyn·s·cm^-5 in the selexipag and placebo groups, respectively (mean difference, -93.5 dyn·s·cm^-5; 95% confidence interval, -156.8, -30.3; p=0.006). The changes in cardiac index (p<0.001) and Borg Dyspnoea Scale score (p=0.036) were also significantly improved over placebo. 6WMD and WHO functional class were not significantly improved. The common adverse events in the selexipag group were corresponded to those generally observed following a prostacyclin analogue is administered.Selexipag significantly improved PVR and other haemodynamic variables in patients with CTEPH, although exercise capacity remained unchanged. Further large-scale investigation is necessary to prove the role of selexipag in CTEPH.

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.

Impact of pulmonary thromboendarterectomy on tricuspid regurgitation in patients with chronic thromboembolic pulmonary hypertension: a single-center prospective cohort experience

Background

For patients with chronic thromboembolic pulmonary hypertension (CTEPH) and tricuspid regurgitation (TR) undergoing pulmonary thromboendarterectomy (PTE), whether concomitant tricuspid annuloplasty should be carried out is still controversial.

Methods

The study population consisted of 45 consecutive patients with CTEPH who were scheduled to undergo PTE. All PTE surgeries were conducted with a median sternotomy and deep hypothermia circulatory arrest (DHCA). We collected and analyzed the demographics, surgical details, echocardiographic parameters, and right heart catheterization (RHC) results of these patients.

Results

Moderate to severe TR was documented in 48.9% (22/45) of the patients pre-operatively and 4.4% (2/45) of the patients post-operatively. In patients with grade 4 TR, severity decreased to grade 2 in 8 and to grade 1 in 1. In patients with grade 3 TR, severity decreased to grade 2 in 9, to grade 1 in 3, and 1 remained unchanged. In patients with grade 2 TR, severity decreased to grade 1 in 8, and 15 remained unchanged. The post-operative TR velocity was decreased significantly (431.9±53.4 vs. 196.5±154.0, P<0.001). Pulmonary artery systolic pressure was 84±17 mmHg pre-operatively and decreased to 38±14 mmHg post-operatively (P<0.001). The pre and post-operative pulmonary diastolic pressure was 29±9 and 17±7 mmHg, respectively (P<0.001). The pre and post-operative mean pulmonary pressure was 48±10 and 24±9 mmHg, respectively (P<0.001). The pulmonary vascular resistance (PVR) (1,025.4±465.0 vs. 476.6±181.2 dynes·sec·cm^-5, P<0.001) and pulmonary artery wedge pressure (PAWP) (9±4 vs. 5±2 mmHg, P<0.001) decreased significantly after operation. The cardiac index (CI) increased significantly (1.9±0.5 vs. 2.3±0.4, P=0.003) after operation.

Conclusions

In conclusion, functional TR could be alleviated after PTE even in patients with high PVR. However, the long-term results need to be further investigated.

Evaluation of Right Ventricular Function on Cardiac Magnetic Resonance Imaging and Correlation With Hemodynamics in Patients With Chronic Thromboembolic Pulmonary Hypertension

Background: Balloon pulmonary angioplasty (BPA) is an alternative therapy for chronic thromboembolic pulmonary hypertension (CTEPH). Right heart catheterization (RHC) is essential to evaluate the efficacy of BPA. Cardiac magnetic resonance imaging (CMR) is also now used to assess the structure and function of the right heart non-invasively. The aim of this study was to correlate improvement in CMR with that on RHC, and compared with improvement in other non-invasive findings after BPA. Methods and Results: Forty-two patients underwent BPA between July 2012 and March 2015, and CMR, electrocardiography (ECG), and echocardiography were performed at the same time before and 6 months after BPA. Median pulmonary vascular resistance (PVR) was improved from 5.7 Wood units (IQR, 3.1-7.9 Wood units) to 2.7 Wood units (IQR, 1.6-3.9 Wood units; P<0.001). Changes in PVR were correlated with the changes in 5 CMR, 9 ECG, and 5 echocardiography parameters. On logistic analysis to identify the indicators of improving PH (i.e., PVR <3 Wood units), 4 CMR parameters were independently correlated with PVR change, one of which was median septal inversion ratio (SIR; 0.59; IQR, 0.54-0.63 to 0.54; IQR, 0.50-0.58, P<0.0001). SIR was the best predictor of PH (OR, 1.27; P<0.05). Conclusions: CMR can be used to estimate hemodynamic changes after BPA, and SIR is useful to predict alleviation of PH.

Chronic Thromboembolic Pulmonary Hypertension: An Update

Chronic thromboembolic pulmonary hypertension (CTEPH) is a progressive pulmonary vascular disease with significant morbidity. It is a result of an alternate natural history in which there is limited resolution of thromboemboli with pulmonary artery obstruction leading to pulmonary hypertension (PH). CTEPH requires a thorough clinical assessment including pulmonary hemodynamics and radiologic evaluation in addition to consultation with an expert center. Surgical intervention remains the optimal management strategy. Select patients may be candidates for catheter-based intervention with balloon pulmonary angioplasty in centers with clinical expertise. Inoperable patients or those with post-intervention PH are treated with pulmonary hypertension-targeted medical therapy.

Meta-analysis of use of balloon pulmonary angioplasty in patients with inoperable chronic thromboembolic pulmonary hypertension

BACKGROUND

Current guidelines give balloon pulmonary angioplasty (BPA) a Class IIb recommendation for use in inoperable chronic thromboembolic pulmonary hypertension (CTEPH), as its safety and efficacy remain poorly defined. We conducted a systematic review and meta-analysis to evaluate BPA effectiveness.

METHODS

Medline, Cochrane Library and Scopus were searched for original studies from database inception dates until 24th May 2018. Prospective studies reporting outcomes before and after BPA in inoperable CTEPH patients were included. Studies with <20 patients were excluded. Data were pooled using a random effects model represented as weighted mean differences with 95% confidence intervals (CIs).

RESULTS

Seventeen noncomparative studies comprising 670 CTEPH patients (mean age 62 years; 68% women) were included. Meta-analysis showed significantly decreased mean pulmonary artery pressure (-14.2 mm Hg [95% CI -18.9, -9.5]), pulmonary vascular resistance (-303.5 dyn·s/cm⁵ [95% CI -377.6, -229.4]) and mean right atrial pressure (-2.7 mm Hg [95% CI -4.1, -1.3]) after BPA. Six-minute walk distance (67.3 m [95% CI 53.8, 80.8]) and cardiac output (0.2 l/min [95% CI 0.0, 0.3]) were significantly increased following BPA. From 12 studies reporting mortality with median follow-up of 9 months after BPA (range, 1-51 months), pooled incidence of short (≤1 month) and long-term mortality (>1 month) was 1.9% and 5.7%, respectively.

CONCLUSION

This systematic review and meta-analysis suggests mildly improved hemodynamics and overall low mortality rates following BPA in inoperable CTEPH patients. This non-comparative evidence can be used to facilitate decision making until the results of larger, controlled studies become available.

Balloon pulmonary angioplasty for the treatment of residual or recurrent pulmonary hypertension after pulmonary endarterectomy

BACKGROUND

Pulmonary endarterectomy (PEA) is the treatment of choice for chronic thromboembolic pulmonary hypertension (CTEPH). However, persistent pulmonary hypertension continues in 5-35% of patients after PEA. Recently, balloon pulmonary angioplasty (BPA) showed promise as a strategy for patients with non-operable CTEPH. Therefore, we investigated the usefulness of BPA for residual pulmonary hypertension after PEA.

METHODS

Fifteen patients with residual pulmonary hypertension after PEA received 71 BPA sessions (4.7 ± 1.4 sessions/patient). The mean time between the PEA and the first BPA session was 28.1 ± 25.8 months. All patients underwent a comprehensive diagnostic work-up, including right heart catheterization, functional and laboratory tests, before, and 6-4 weeks after the BPA sessions.

RESULTS

After BPA, the mean pulmonary arterial pressure decreased from 44.7 ± 6.4 to 30.8 ± 7.5 mm Hg (31% decline; p < 0.001). Pulmonary vascular resistance decreased from 551.9 ± 185.2 to 343.8 ± 123.8 dyn∗s/cm^-5 (38% decline; p < 0.001). The 6-min walking distance increased from 383 ± 104 to 476 ± 107 m (mean change +93 m; p < 0.001). In two sessions (2.8%), serious periprocedural complications occurred. During a mean follow-up of 18 ± 14.3 months, one patient died two months after the last BPA session. Fourteen patients survived.

CONCLUSIONS

BPA could be a promising therapeutic strategy for persistent pulmonary hypertension after PEA in patients with CTEPH.

A survey on pulmonary thromboendarterectomy in the Asia-Pacific region

Background Surgical pulmonary thromboendarterectomy has been established as the treatment of choice for chronic thromboembolic pulmonary hypertension. We conducted a survey among Asia-Pacific cardiothoracic surgeons to examine their current practice demographics and reflect their views on the future prospects for pulmonary thromboendarterectomy surgery. Methods All cardiothoracic surgeons who were registered on the CTSNet.org website and based in the Asia-Pacific region were invited to participate in an online survey. The electronic questionnaire was completed by 172 (6.3%) surgeons. Responses were recorded anonymously and tabularized as absolute figures and fractions. Results Pulmonary thromboendarterectomy surgery has been performed by few Asia-Pacific surgeons and in small numbers of patients, but survival rates and functional outcomes were satisfactory in most experiences. Failures were thought to have resulted primarily from the difficulty in selecting suitable candidates for surgery. The need for greater clinical experience was clear, yet this might be hampered by the limited recognition of pulmonary thromboendarterectomy surgery as a potential cure for chronic thromboembolic pulmonary hypertension. Most surgeons considered that this procedure should be restricted to designated expert centers, and acknowledged the need to organize dedicated regional meetings where clinical practice guidelines can be established and updated as appropriate for regional healthcare facilities. Conclusions Although much effort is needed before pulmonary thromboendarterectomy surgery becomes widely adopted in the Asia-Pacific region, many surgeons and centers are already seeking its implementation. Designating expert centers, bringing together a regional working group on pulmonary thromboendarterectomy, and establishing clinical practice guidelines as appropriate for regional healthcare facilities were recommended.

An epidemiological analysis of the burden of chronic thromboembolic pulmonary hypertension in the USA, Europe and Japan

Epidemiological data for chronic thromboembolic pulmonary hypertension (CTEPH) are limited and there are conflicting reports regarding its pathogenesis.

A literature review was conducted to identify CTEPH epidemiological data up to June 2014. Data were analysed to provide estimates of the incidence of CTEPH in the USA, Europe and Japan. An epidemiological projection model derived country-specific estimates of future incidence and diagnosis rates of CTEPH.

Overall, 25 publications and 14 databases provided quantitative epidemiological data. In the USA and Europe, the crude annual incidence of diagnosed pulmonary embolism and crude annual full (i.e. diagnosed and undiagnosed) incidence of CTEPH were 66–104 and 3–5 cases per 100 000 population, respectively, while in Japan these rates were lower at 6.7 and 1.9 per 100 000 population, respectively. In 2013, 7–29% of CTEPH cases in Europe and the USA were diagnosed, and the majority of patients were in New York Heart Association functional class III/IV at diagnosis. The projection model indicated that incidence of CTEPH will continue to increase over the next decade.

These data suggest that CTEPH is underdiagnosed and undertreated, and there is an urgent need to increase awareness of CTEPH. High-quality epidemiological studies are required to increase understanding of CTEPH.

Epidemiological data suggest that CTEPH is underdiagnosed and there is an urgent need to improve disease awarenesshttp://ow.ly/J0KC3095U2W

Pulmonary endarterectomy in the elderly: safety, efficacy and risk factors

AIMS

Pulmonary endarterectomy (PEA) is the treatment of choice for patients with chronic thromboembolic pulmonary hypertension, but there are few data in the literature about the results of this procedure in the elderly. In this study, we aimed to assess whether this type of surgery is effective and well tolerated for the elderly.

METHODS

A total of 264 consecutive patients who underwent PEA between January 2008 and December 2012 were reviewed. PEA was performed under cardiopulmonary bypass and hypothermic ventricular fibrillation, with the aorta left unclamped. The population was dichotomized according to age into the following two groups: below 70 years (n = 176, younger patients) and at least 70-year-olds (n = 88, elderly patients). Regression models were used to identify predictors of hospital mortality and postoperative adverse events, and their interaction with age was tested.

RESULTS

Hospital mortality was slightly, but not significantly higher in elderly patients (9.1 vs. 5.1%; P = 0.22). Effect modification by history of smoking and preoperative O2 therapy was present. The cumulative survival at 1, 2, and 4 years was 93, 92, and 91% among younger patients; and 88, 86, and 86% among older patients (P = 0.19). Clinical and hemodynamic improvement was similar in the two groups.

CONCLUSION

Despite a slightly higher short-term mortality, PEA is feasible and well tolerated for the vast majority of the elderly patients. Clinical and hemodynamic improvements are outstanding, with satisfactory long-term survival rates.

A Model of Anterograde Oxygenated Lung Blood Flow in Acardia

In extreme situations such as hyperacute rejection of heart transplant or major heart trauma, heart explantation and extracorporeal membrane oxygenation (ECMO) hemodynamic support might be the only means for survival. In our previous model of acardia, pulmonary artery (PA) was clamped and did not receive any anterograde blood flow. A model of anterograde PA perfusion might be necessary to avoid ischemic pulmonary damage in prolonged ECMO in acardia. The aim of this study was to describe the surgical technique and to determine the feasibility of an anterograde lung perfusion in acardia through the anastomosis of the right internal mammary artery (RIMA) to the PA. A venoarterial cardiopulmonary bypass was established in three pigs (72 ± 2.6 kg) by the transjugular insertion to the caval axis of a double-staged cannula with carotid artery return. Heart was excised and ECMO was established as previously reported. Right internal mammary artery was harvested and after measurement of its output (93.3 ± 5.8 ml/min, representing 2.17% ± 0.15% of total pump flow), it was anastomosed to PA. Right internal mammary artery anastomosis to PA is a feasible, safe, and easy to perform maneuver assuring an anterograde lung perfusion in acardia.

Heart rate response during 6-minute walking testing predicts outcome in operable chronic thromboembolic pulmonary hypertension

BACKGROUND

Six-minute walk test (6MWT) is routinely performed in chronic thromboembolic pulmonary hypertension (CTEPH) before pulmonary endarterectomy (PEA). However, the clinical relevance of heart rate response (ΔHR) and exercise-induced oxygen desaturation (EID) during 6MWT is remaining unknown.

METHODS

Patients undergoing PEA in our center between 03/2013-04/2014 were assessed prospectively with hemodynamic and exercise parameters prior to and 1 year post-PEA. Patients with symptomatic chronic thromboembolic disease (mean pulmonary artery pressure (mPAP) <25 mmHg) and clinical relevant obstructive pulmonary disease were excluded. The following definitions were used: ΔHR = (peak HR - resting HR), percent heart rate reserve (HRR) = (peak HR -rest HR)/(220 - age - rest HR) x 100 and EID = SpO2 ≤88 %.

RESULTS

Thirty-seven patients (of 116 patients screened) with mPAP of 43.2 ± 8.7 mmHg, pulmonary vascular resistance (PVR) of 605.5 ± 228.7 dyn*s/cm(5), cardiac index (CI) of 2.4 ± 0.5 l/min/m(2) and a 6MWT-distance of 404.7 ± 148.4 m and a peak VO2 of 12.3 ± 3.4 ml/min/kg prior to PEA were included. Baseline ΔHR during 6MWT was significantly associated with PVR 1 year post-PEA using linear regression analysis (r = 0.43, p = 0.01). Multivariate analysis indicated an association of HRR during 6MWT and residual PH with a hazard ratio of 1.06 (95 % Confidence interval for hazard ratio 0.99-1.14, p = 0.08). EID was observed commonly during 6MWT but no correlations to outcome parameters were found.

CONCLUSIONS

This is the first prospective study to describe an association of ΔHR during 6MWT with pulmonary hemodynamics 1 year post-PEA. Our preliminary results indicate that HRR derived from 6MWT is of clinical significance. EID was commonly observed, albeit failed as a significant prognostic factor.

Treatment of patients with chronic thrombo embolic pulmonary hypertension: focus on riociguat

Chronic thromboembolic pulmonary hypertension (CTEPH) is a disease of the pulmonary vascular bed that is characterized by elevations in the mean pulmonary artery pressure in the setting of perfusion defects on ventilation–perfusion scan, and subsequently confirmed by pulmonary angiography. CTEPH, or World Health Organization (WHO) group 4 pulmonary hypertension, is a result of unresolved thromboembolic obstruction in the pulmonary arteries. Pulmonary endarterectomy (PEA) is the treatment of choice for CTEPH as it is a potentially curative therapy. However, up to one-third of patients are not candidates for the surgery, either due to distal and inaccessible nature of the lesions or comorbid conditions. Due to remodeling that occurs in nonobstructed pulmonary vessels, a portion of patients who have undergone PEA have residual CTEPH after the procedure, attributable to high shear stress prior to PEA. This phenomenon has led to the understanding of a so-called “two-compartment model” of CTEPH, opening the door to pharmacologic treatment strategies. In 2013, riociguat, a soluble guanylate cyclase stimulator, was approved in the US and Europe for the treatment of inoperable or persistent/recurrent CTEPH. This article reviews the current management of CTEPH with a focus on riociguat.

Dynamic Risk Stratification of Patient Long-Term Outcome After Pulmonary Endarterectomy: Results From the United Kingdom National Cohort

BACKGROUND

Chronic thromboembolic pulmonary hypertension results from incomplete resolution of pulmonary emboli. Pulmonary endarterectomy (PEA) is potentially curative, but residual pulmonary hypertension following surgery is common and its impact on long-term outcome is poorly understood. We wanted to identify factors correlated with poor long-term outcome after surgery and specifically define clinically relevant residual pulmonary hypertension post-PEA.

METHODS AND RESULTS

Eight hundred eighty consecutive patients (mean age, 57 years) underwent PEA for chronic thromboembolic pulmonary hypertension. Patients routinely underwent detailed reassessment with right heart catheterization and noninvasive testing at 3 to 6 months and annually thereafter with discharge if they were clinically stable at 3 to 5 years and did not require pulmonary vasodilator therapy. Cox regressions were used for survival (time-to-event) analyses. Overall survival was 86%, 84%, 79%, and 72% at 1, 3, 5, and 10 years for the whole cohort and 91% and 90% at 1 and 3 years for the recent half of the cohort. The majority of patient deaths after the perioperative period were not attributable to right ventricular failure (chronic thromboembolic pulmonary hypertension). At reassessment, a mean pulmonary artery pressure of ≥30 mm Hg correlated with the initiation of pulmonary vasodilator therapy post-PEA. A mean pulmonary artery pressure of ≥38 mm Hg and pulmonary vascular resistance ≥425 dynes·s(-1)·cm(-5) at reassessment correlated with worse long-term survival.

CONCLUSIONS

Our data confirm excellent long-term survival and maintenance of good functional status post-PEA. Hemodynamic assessment 3 to 6 months and 12 months post-PEA allows stratification of patients at higher risk of dying of chronic thromboembolic pulmonary hypertension and identifies a level of residual pulmonary hypertension that may guide the long-term management of patients postsurgery.

The Clinical Significance of HbA1c in Operable Chronic Thromboembolic Pulmonary Hypertension

Background

Glycosylated hemoglobin A1c (HbA1c) has been proposed as an independent predictor of long-term prognosis in pulmonary arterial hypertension. However, the clinical relevance of HbA1c in patients with operable chronic thromboembolic pulmonary hypertension (CTEPH) remains unknown. The aim of the present study was to investigate the clinical significance of HbA1c as a biomarker in CTEPH.

Methods

Prospectively, 102 patients underwent pulmonary endarterectomy (PEA) in our national referral center between March 2013 and March 2014, of which after exclusion 45 patients were analyzed. HbA1c- levels, hemodynamic and exercise parameters were analyzed prior and one-year post-PEA.

Results

45 patients (BMI: 27.3 ± 6.0 kg/m²; age: 62.7 ± 12.3 years) with a mean pulmonary arterial pressure (mPAP) of 43.6 ± 9.4 mmHg, a pulmonary vascular resistance (PVR) of 712.1 ± 520.4 dyn*s/cm⁵, a cardiac index (CI) of 2.4 ± 0.5 l/min/m² and a mean HbA1c-level of 39.8 ± 5.6 mmol/mol were included. One-year post-PEA pulmonary hemodynamic and functional status significantly improved in our cohort. Baseline HbA1c-levels were significantly associated with CI, right atrial pressure, peak oxygen uptake and the change of 6-minute walking distance using linear regression analysis. However, using logistic regression analysis baseline HbA1c-levels were not significantly associated with residual post-PEA PH.

Conclusions

This is the first prospective study to describe an association of HbA1c-levels with pulmonary hemodynamics and exercise capacity in operable CTEPH patients. Our preliminary results indicate that in these patients impaired glucose metabolism as assessed by HbA1c is of clinical significance. However, HbA1c failed as a predictor of the hemodynamic outcome one-year post-PEA.

Antithrombotic Therapy for VTE Disease: CHEST Guideline and Expert Panel Report

BACKGROUND

We update recommendations on 12 topics that were in the 9th edition of these guidelines, and address 3 new topics.

METHODS

We generate strong (Grade 1) and weak (Grade 2) recommendations based on high- (Grade A), moderate- (Grade B), and low- (Grade C) quality evidence.

RESULTS

For VTE and no cancer, as long-term anticoagulant therapy, we suggest dabigatran (Grade 2B), rivaroxaban (Grade 2B), apixaban (Grade 2B), or edoxaban (Grade 2B) over vitamin K antagonist (VKA) therapy, and suggest VKA therapy over low-molecular-weight heparin (LMWH; Grade 2C). For VTE and cancer, we suggest LMWH over VKA (Grade 2B), dabigatran (Grade 2C), rivaroxaban (Grade 2C), apixaban (Grade 2C), or edoxaban (Grade 2C). We have not changed recommendations for who should stop anticoagulation at 3 months or receive extended therapy. For VTE treated with anticoagulants, we recommend against an inferior vena cava filter (Grade 1B). For DVT, we suggest not using compression stockings routinely to prevent PTS (Grade 2B). For subsegmental pulmonary embolism and no proximal DVT, we suggest clinical surveillance over anticoagulation with a low risk of recurrent VTE (Grade 2C), and anticoagulation over clinical surveillance with a high risk (Grade 2C). We suggest thrombolytic therapy for pulmonary embolism with hypotension (Grade 2B), and systemic therapy over catheter-directed thrombolysis (Grade 2C). For recurrent VTE on a non-LMWH anticoagulant, we suggest LMWH (Grade 2C); for recurrent VTE on LMWH, we suggest increasing the LMWH dose (Grade 2C).

CONCLUSIONS

Of 54 recommendations included in the 30 statements, 20 were strong and none was based on high-quality evidence, highlighting the need for further research.

Pulmonary endarterectomy for pulmonary hypertension from septic emboli

Pulmonary endarterectomy (PEA) can significantly increase long-term survival in patients with chronic thromboembolic pulmonary hypertension; however, the role of PEA for chronic thromboembolic pulmonary hypertension due to pulmonary valve endocarditis is controversial. A critically ill 61-year-old man with intractable right ventricular heart failure was found to have chronic thromboembolic pulmonary hypertension due to Streptococcus bovis pulmonary valve endocarditis and underwent successful pulmonary valve replacement and PEA. The successful outcome in this case suggests that PEA should be considered in patients with this condition.

Contribution of inflammation and impaired angiogenesis to the pathobiology of chronic thromboembolic pulmonary hypertension

Deficient angiogenesis and systemic inflammation could be involved in the pathophysiology of chronic thromboembolic pulmonary hypertension (CTEPH). We aimed to characterise the histopathology of pulmonary vascular lesions from 52 CTEPH patients who underwent a pulmonary endarterectomy (PEA) and investigate a potential link between clinical, biological and morphometric parameters.

Collagen, elastin, fibrin, lipid, endothelial, smooth muscle and inflammatory cell content was investigated using immunohistochemistry. Qualitative changes were evaluated using severity scores. Circulating levels of inflammatory mediators were measured using ELISA.

Neointima, thrombotic, recanalised and atherosclerotic lesions were found. Accumulation of macrophages, T-lymphocytes and neutrophils was found mainly in atherosclerotic and thrombotic lesions. Angiogenesis was observed in all kinds of lesions; low-scored angiogenesis predicted adverse outcome, including persistent pulmonary hypertension post-PEA, start of medical therapy and poor survival. C-reactive protein (CRP), interleukin-10, monocyte chemotactic protein-1, macrophage inflammatory protein-1α and matrix metalloproteinase (MMP)-9 were significantly elevated in CTEPH patients. Plasma CRP and MMP-9 levels correlated with neutrophil and macrophage accumulation, respectively.

Enhanced systemic inflammation parallels local inflammatory cell infiltration in major pulmonary arteries at advanced stages of CTEPH. Impaired neovascularisation is associated with poor survival, start of medical treatment and persistent pulmonary hypertension post-PEA. These findings suggest that inflammation and impaired angiogenesis could contribute to the progression of the disease.

Balloon pulmonary angioplasty: an additional treatment option to improve the prognosis of patients with chronic thromboembolic pulmonary hypertension

AIMS

To evaluate the efficacy and safety of balloon pulmonary angioplasty (BPA) in patients with non-operable chronic thromboembolic pulmonary hypertension (CTEPH) using the results of pulmonary endarterectomy (PEA) for operable patients as a reference, and annotate the role of BPA in the management of CTEPH.

METHODS AND RESULTS

Data from 53 CTEPH patients were collected retrospectively. Twenty-four operable patients underwent PEA, and 29 non-operable patients underwent BPA. Patients who underwent BPA showed improved mean pulmonary arterial pressure, pulmonary vascular resistance, and cardiac output (39.4±6.9 to 21.3±5.6 mmHg, 763±308 to 284±128 dyn·s-1·cm-5, 3.47±0.80 to 4.26±1.15 L/min, respectively); patients who received PEA showed similar efficacy (44.4±11.0 to 21.6±6.7 mmHg, 781±278 to 258±125 dyn·s-1·cm-5, 3.35±1.11 to 4.44±1.58 L/min, respectively). The mortality rates of BPA and PEA patients were 3.4% and 8.3%, respectively.

CONCLUSIONS

The efficacy and safety of BPA for non-operable cases were similar to those achieved using PEA for operable cases. BPA could be an additional treatment option for non-operable CTEPH patients, and most CTEPH patients can be satisfactorily treated by BPA or PEA.

Central and peripheral pulmonary vascular resistance: Implications for who should undergo pulmonary thromboendarterectomy

Pulmonary thromboendarterectomy remains a technically challenging procedure with variable outcomes with regard to improvement in pulmonary function. Reducing the resistance to flow between the pulmonary valve and the pulmonary capillary bed is the key aim of surgery. The resistance to flow is due to the combination of resistance due to the central clot and distal capillary resistance. We hypothesise that the use of fluid mechanics in combination with modern radiology and electronic circuit theory can potentially predict who should or should not undergo a thromboendarterectomy. Electronic circuit theory of two resistors in series was utilised to demonstrate the concept of a model of a central clot and the peripheral pulmonary capillary bed. A simplified 2D model of the lungs utilising finite element analysis and Poiseuille's law was constructed for proof of principle. Modelling predicts that cardiac output and anatomical obstruction interplay and can have profound effects on the outcomes after thromboendarterectomy. Identical pulmonary artery pressures, due to differing cardiac outputs and identical anatomical obstructions due to thrombus can have very different physiological outcomes with regard to changes in pulmonary artery pressure. Modelling the pulmonary vasculature to determine central and peripheral pulmonary vascular resistance may help in predicting who should undergo pulmonary thromboendarterectomy. Mathematical modelling can potentially predict which patients have haemodynamically significant clots in their pulmonary arteries that thromboendarterectomy may potentially help in the setting of pulmonary capillary disease.

Neutrophil/Lymphocyte Ratio Can Predict Postoperative Mortality in Patients with Chronic Thromboembolic Pulmonary Hypertension

OBJECTIVE

The aim of our study was to investigate clinical importance of neutrophil/ lymphocyte ratio in patients with Chronic thromboembolic pulmonary hypertension.

METHODS

125 consecutive patients with a diagnosis of Chronic thromboembolic pulmonary hypertension were operated pulmonary thromboendarterectomy in our center between February 2011 and August 2013. 106 patients included into the study due to limitations. The patients were classified into two groups as patients discharged alive (Group 1) and those dying in the hospital (Group 2). Baseline neutrophil/lymphocyte ratio level was measured by dividing neutrophil count to lymphocyte count.

RESULTS

84 patients (79%) were in Group 1, 22 patients (21%) were in Group 2. Patients with higher neutrophil/lymphocyte ratio in admission have a significantly higher mortality rate and postoperative pulmonary vascular resistance was found statistically significant variable to predict the mortality. Receiver operator characteristic (ROC) analysis revealed that using a cut-off point of 2.54, admission neutrophil/lymphocyte ratio predicts mortality. Also, correlation analysis showed a significant correlation between preoperative pulmonary vascular resistance and neutrophil/lymphocyte ratio.

CONCLUSION

The neutrophil/lymphocyte ratio level may be a useful and noninvasive biomarker for operative risk stratification for mortality after pulmonary thromboendarterectomy.

Additional percutaneous transluminal pulmonary angioplasty for residual or recurrent pulmonary hypertension after pulmonary endarterectomy

BACKGROUND

Pulmonary endarterectomy (PEA) has been the most effective therapy for chronic thromboembolic pulmonary hypertension (CTEPH). However, residual or recurrent pulmonary hypertension often persists after PEA. Recently, catheter-based angioplasty, called percutaneous transluminal pulmonary angioplasty (PTPA) or balloon pulmonary angioplasty, has been developed as a promising strategy for CTEPH. Therefore, the usefulness of PTPA for residual or recurrent pulmonary hypertension after PEA was investigated.

METHODS

Thirty-nine patients underwent PEA from January 2000, and a total of 423 consecutive PTPA sessions in 110 patients were performed from January 2009 to May 2014. Of them, 9 patients (23.0% of 39 patients undergoing PEA and 8.2% of 110 patients undergoing PTPA) had undergone previous PEA and additional PTPA.

RESULTS

In these 9 patients, pulmonary vascular resistance (PVR) was 15.6 (7.8-18.9) wood units at baseline, and significantly improved after PEA [5.6 (3.5-6.5) wood units] (p<0.05). However, PVR gradually deteriorated before PTPA [8.1 (6.1-12.3) wood units] compared to after PEA, suggesting that these 9 patients had residual or recurrent pulmonary hypertension after PEA. PTPA was performed at 4.1 (2.7-7.9) years after PEA. Follow-up catheterization at 1.9 (1.3-3.3) years after PTPA revealed significant improvement of PVR [4.2 (2.8-4.8) wood units] (p<0.05).

CONCLUSIONS

A hybrid approach combining PEA and additional PTPA may be reasonable for patients with both proximal and very distal lesions not easily approachable by PEA. PTPA could be a promising alternative therapeutic strategy for residual or recurrent pulmonary hypertension after PEA.

Pulmonary thromboendarterectomy in 106 patients with chronic thromboembolic pulmonary hypertension

INTRODUCTION

Pulmonary thromboendarterectomy is the treatment of choice in chronic thromboembolic pulmonary hypertension. We report our experience with this technique.

METHODS

Between February 1996 and June 2014, we performed 106 pulmonary thromboendarterectomies. Patient population, morbidity and mortality and the long-term results of this technique (survival, functional improvement and resolution of pulmonary hypertension) are described.

RESULTS

Subjects' mean age was 53±14 years. A total of 89% were WHO functional class III-IV, presurgery mean pulmonary pressure was 49±13mmHg and mean pulmonary vascular resistance was 831±364 dynes.s.cm(-5). In-hospital mortality was 6.6%. The most important post-operative morbidity was reperfusion pulmonary injury, in 20% of patients; this was an independent risk factor (p=0.015) for hospital mortality. With a 31-month median follow-up (interquartile range: 50), 3- and 5-year survival was 90 and 84%. At 1 year, 91% were WHO functional class I-II; mean pulmonary pressure (27±11mmHg) and pulmonary vascular resistance (275±218 dynes.s.cm(-5)) were significantly lower (p<0.05) than before the intervention. Although residual pulmonary hypertension was detected in 14 patients, their survival at 3 and 5 years was 91 and 73%, respectively.

CONCLUSIONS

Pulmonary thromboendarterectomy offers excellent results in chronic thromboembolic pulmonary hypertension. Long-term survival is good, functional capacity improves, and pulmonary hypertension is resolved in most patients.

[Inhaled iloprost, a selective pulmonary vasodilator. Clinical evidence from its use in perioperative pulmonary hypertension cardiovascular surgery]

Inhaled iloprost is one of the most recent drugs from prostanoids group's in the treatment of pulmonary arterial hypertension. His place in pulmonary hypertension seen in the perioperative cardiovascular surgery has not been defined. In this review we analyze pulmonary hypertension group's susceptibles of cardiac surgery and its importance, besides the current clinical evidence from drug use in this context.

Soluble guanylate cyclase: a new therapeutic target for pulmonary arterial hypertension and chronic thromboembolic pulmonary hypertension

Nitric oxide (NO) activates soluble guanylate cyclase (sGC) by binding its prosthetic heme group, thereby catalyzing cyclic guanosine monophosphate (cGMP) synthesis. cGMP causes vasodilation and may inhibit smooth muscle cell proliferation and platelet aggregation. The NO-sGC-cGMP pathway is disordered in pulmonary arterial hypertension (PAH), a syndrome in which pulmonary vascular obstruction, inflammation, thrombosis, and constriction ultimately lead to death from right heart failure. Expression of sGC is increased in PAH but its function is reduced by decreased NO bioavailability, sGC oxidation and the related loss of sGC's heme group. Two classes of sGC modulators offer promise in PAH. sGC stimulators (e.g., riociguat) require heme-containing sGC to catalyze cGMP production, whereas sGC activators (e.g., cinaciguat) activate heme-free sGC. Riociguat is approved for PAH and yields functional and hemodynamic benefits similar to other therapies. Its main serious adverse effect is dose-dependent hypotension. Riociguat is also approved for inoperable chronic thromboembolic pulmonary hypertension.

Demographics, clinical characteristics, health resource utilization and cost of chronic thromboembolic pulmonary hypertension patients: retrospective results from six European countries

Background

Chronic Thromboembolic Pulmonary Hypertension (CTEPH) results from incomplete resolution of a pulmonary embolus, leading to pulmonary hypertension and progressive right heart failure and death. We aimed to describe the demographics, treatment patterns, health resource utilization and related costs of patients with CTEPH.

Methods

In specialized PH centres across six European countries, medical charts of CTEPH patients on PH medication were retrospectively extracted (chart review between 2006 and 2009). Resource utilization was valued using country-specific unit costs. Descriptive statistical analyses were performed.

Results

Twenty-one hospitals documented 119 consecutive CTEPH patients over an average of 25.4 months. Patients were inoperable (83.9%) or persistent after surgery (16.0%) with mean age 67.5 ± 12.3 years, 61% were female. The average 6-minute walking distance was 298 ± 120 meters, and NYHA class II/III/IV was 27/59/14%. At baseline, 59.7% patients received endothelin receptor antagonist, 34.4% phosphodiesterase-5 inhibitors, and 5.8% prostacyclin. Adding a second PH medication was the most common regimen change. CTEPH patients experienced 1.8 ± 2.2 hospitalizations per year accounting for 14.8 ± 26.1 days in hospital. Patients paid on average 2.8 office visits per year to their general practitioner and 1.3 visits to a specialist. Unadjusted annual mortality rate was 6.0%. Annual cost of PH specific medication was the predominant economic factor averaging € 36,768 per year. Costs for hospitalizations (€ 4,496) and concomitant medications (€ 2,510) were substantially lower. Other health care resource items only accounted for marginal additional costs.

Conclusion

CTEPH patients are characterised by substantial morbidity and mortality. Health care utilisation, predominantly due to off-label use of PH drugs, is significant.

Pulmonary Endarterectomy: Assessment of Operability, Surgical Description, and Post-op Care

Chronic thromboembolic pulmonary hypertension (CTEPH) is defined as a mean pulmonary artery pressure ≥25 mm Hg and pulmonary artery wedge pressure ≤15 mm Hg in the presence of occlusive thrombi within the pulmonary arteries. Surgical pulmonary thromboendarterectomy (PTE) is considered the best treatment option for CTEPH.

Pulmonary endarterectomy for chronic thrombo-embolic pulmonary hypertension: an institutional experience

OBJECTIVE

Pulmonary endarterectomy (PEA) is the treatment of choice for patients with chronic thrombo-embolic pulmonary hypertension (CTEPH). The aim of this study was to review our initial experience since the implementation of our program.

METHODS

Data were collected prospectively on all patients who underwent PEA between March 2011 and March 2012.

RESULTS

Forty-nine patients (20 male, 29 female, mean age 47.7 years) underwent surgery. The preoperative New York Heart Association class distribution showed the majority to be in class III or IV (n = 40). Mortality rate was 14.2% (n = 7) and the morbidity rate was 26.5% (n = 13). After PEA, the durations of mechanical ventilation, intensive care stay and hospital stay before discharge were 49.7 ± 46.1 h, 6.5 ± 5.0 days and 12.9 ± 7.5 days, respectively. The systolic and mean pulmonary artery pressure (PAP) fell significantly from 87.0 ± 26.6 mmHg and 53.8 ± 14.5 before, to 41.5 ± 12.4 mmHg and 28.5 ± 10.5 after surgery (P < 0.001 and P < 0.001, respectively). Pulmonary vascular resistance (PVR) also improved significantly from 808 ± 352.0 to 308 ± 91 dyn•s•cm(-5) (P < 0.001). Univariate analysis showed that preoperative systolic PAP, tricuspid annular plane systolic excursion, right atrial volume, right atrial pressure, forced expiratory volume in 1 s, forced vital capacity, preoperative PVR, postoperative PVR, the duration of circulatory arrest and postoperative use of extracorporeal membrane oxygenation were risk factors for mortality (P < 0.05). According to multivariate analyses, only prolonged mechanical ventilation was selected as predictive risk factor for morbidity (P = 0.005). After a median follow-up of 6.1 months, two patients died due to cerebrovascular disease and one patient needed targeted pulmonary hypertension therapy. The rest of the 39 patients showed marked improvements in their clinical status.

CONCLUSIONS

Starting a pulmonary endarterectomy program with acceptable mortality and morbidity rates and satisfactory early-term outcomes increases awareness of the CTEPH and surgery. Preoperative factors can primarily predict postoperative outcome after PEA. Identifying the risk factors in order to achieve a good result is important for the success of a PEA program. Therefore all patients diagnosed with CTEPH should be referred for consideration of PEA in a specialized centre.

Chronic thromboembolic pulmonary hypertension: an underdiagnosed entity?

Chronic thromboembolic pulmonary hypertension (CTEPH) is the only cause of pulmonary hypertension for which there is a potential cure, which is in the form of pulmonary endarterectomy. There is a strong link between pulmonary embolism (PE) and the development of CTEPH. Although CTEPH was initially believed to be a rare complication, this belief has been reconsidered following several studies suggesting that up to 8.8% of patients develop CTEPH within the 2 years after PE. However, considering the incidence of PE, there is a significant discrepancy in the number of patients who are diagnosed, referred, and treated for CTEPH. Potential reasons for this include its often vague clinical presentation, the variable association of CTEPH with PE, and discrepancies when interpreting imaging studies. Underdiagnosis of CTEPH is preventing patients from accessing potentially curative therapy. Increased awareness about this condition is an important initial step to improving diagnostic rates and treatment.