Recent progress in the diagnosis and management of chronic thromboembolic pulmonary hypertension

Prevalence and Clinical Characteristics of Heterozygous RNF213 p.Arg4810Lys Variant Carriers Diagnosed With Chronic Thromboembolic Pulmonary Hypertension

BACKGROUND

Ring finger protein 213 (RNF213) p.Arg4810Lys is a susceptibility gene for moyamoya disease, peripheral pulmonary artery stenosis (PPS), and other vascular diseases and thrombosis. We investigated the prevalence and clinical characteristics of RNF213 variant carriers diagnosed with chronic thromboembolic pulmonary hypertension (CTEPH).

METHODS AND RESULTS

We retrospectively analyzed the prevalence of the RNF213 p.Arg4810Lys variant in patients diagnosed with CTEPH (n=112) and PPS (n=10). Clinical and angiographic characteristics were evaluated between RNF213 variant carriers diagnosed with CTEPH and noncarriers with CTEPH and homozygous variant carriers with PPS. Eight heterozygous RNF213 p.Arg4810Lys variant carriers (7.1%) were identified among patients diagnosed with CTEPH, while 5 patients with PPS (50%) carried the homozygous variant. The clinical characteristics of heterozygous variant carriers with CTEPH were not remarkably different from those of noncarriers with CTEPH. All heterozygous variant carriers with CTEPH showed webs/bands lesions at the segmental/subsegmental level, with 75% showing distal tortuous vessels. None of the heterozygous variant carriers with CTEPH exhibited the string-of-beads pattern or elongated stenosis. Homozygous variant carriers with PPS showed the string-of-beads pattern, elongated stenosis, and distal tortuous vessels without webs/bands lesions.

CONCLUSIONS

A subset of patients diagnosed with CTEPH (7.1%) carried the heterozygous RNF213 p.Arg4810Lys variant. Clinical and angiographic characteristics of heterozygous variant carriers were not remarkably different from those of noncarriers of CTEPH. However, both heterozygous variant carriers with CTEPH and homozygous variant carriers with PPS showed tortuous vessels on angiography.

Clinical significance of lung cross-sectional area measured by computed tomography in chronic thromboembolic pulmonary hypertension: The correlation with pulmonary hemodynamics and the limitations

The percentage cross-sectional area of the lung under five (%CSA<5) is the percentage of pulmonary vessels with <5 mm2 area relative to the total lung area on computed tomography (CT). The extent that %CSA<5 is related to pulmonary hemodynamics in patients with chronic thromboembolic pulmonary hypertension (CTEPH) is unclear, as is the effect of pulmonary endarterectomy (PEA) on %CSA<5. Therefore, we aimed to evaluate the clinical significance of %CSA<5 in patients with CTEPH. We studied 98 patients (64 females, mean age 62.5 ± 11.9 years), who underwent CT with %CSA<5 measurement and right heart catheterization (RHC). Patients were classified into groups based on eligibility for PEA. We compared the %CSA<5 with pulmonary hemodynamics measured by RHC in various groups. In 38 patients who underwent PEA, the relationship between %CSA<5 and pulmonary hemodynamics was also evaluated before and after PEA. Significant correlations between %CSA<5 and pulmonary vascular resistance, and compliance, and pulmonary artery pulse pressure were observed in all patients. Pulmonary hemodynamics in the patients who underwent or were eligible for PEA showed a significant correlation with %CSA<5. Additionally, %CSA<5 was significantly lower in the postoperative than in the preoperative group. There was no correlation between changes in %CSA<5 and pulmonary hemodynamics before and after PEA. Furthermore, %CSA<5 did not correlate significantly with prognosis. %CSA<5 may reflect pulmonary hemodynamics in CTEPH with central thrombosis. Furthermore, %CSA<5 was reduced by PEA postoperatively. However, %CSA<5 is not a prognostic indicator, its clinical usefulness in CTEPH patients is limited, and further validation is required.

Evaluation of balloon pulmonary angioplasty using lung perfusion SPECT in patients with chronic thromboembolic pulmonary hypertension

BACKGROUND

The aim of this study was to evaluate the effect of balloon pulmonary angioplasty (BPA) using lung perfusion single-photon emission computed tomography (SPECT) in patients with chronic thromboembolic pulmonary hypertension (CTEPH).

METHODS AND RESULTS

20 consecutive patients (64 ± 15 years) who were diagnosed with CTEPH and underwent BPA were included in this study. All patients underwent lung perfusion SPECT before and after BPA. The relationship between functional %volume of the lung calculated from the lung perfusion SPECT (FVL-LPSPECT), and other clinical parameters before and after BPA was assessed using the Wilcoxon signed-rank test. The correlation between each parameter and mean pulmonary artery pressure (mPAP) using the Spearman's correlation was performed. To determine predictors of mPAP for evaluating treatment effectiveness, significant parameters were included in multiple regression analysis. After BPA, world health organization functional classification, six-minute walk distance (6MWD), mPAP, and FVL-LPSPECT significantly improved. FVL-LPSPECT (r = - 0.728, P < 0.001) and 6MWD (r = - 0.571, P = 0.009) were significant correlation of mPAP. In the multiple regression analysis, FVL-LPSPECT was the most significant predictor of improvement in mPAP after BPA (P < 0.001).

CONCLUSIONS

This study demonstrated that the lung perfusion SPECT could be a potential measurement of the effectiveness of BPA in patients with CTEPH.

Balloon pulmonary angioplasty versus riociguat in inoperable chronic thromboembolic pulmonary hypertension (MR BPA): an open-label, randomised controlled trial

BACKGROUND

Treatment options for patients with chronic thromboembolic pulmonary hypertension ineligible for pulmonary endarterectomy (inoperable CTEPH) include balloon pulmonary angioplasty (BPA) and riociguat. However, these two treatment options have not been compared prospectively. We aimed to compare the safety and efficacy of BPA and riociguat in patients with inoperable CTEPH.

METHODS

This open-label, randomised controlled trial was conducted at four high-volume CTEPH centres in Japan. Patients aged 20-80 years with inoperable CTEPH (mean pulmonary arterial pressure ≥25 to &lt;60 mm Hg and pulmonary artery wedge pressure ≤15 mm Hg) and WHO functional class II or III were randomly assigned (1:1) to BPA or riociguat via a computer program located at the registration centre using a minimisation method with biased-coin assignment. In the BPA group, the aim was for BPA to be completed within 4 months of the initial date of the first procedure. BPA was repeated until mean pulmonary arterial pressure decreased to less than 25 mm Hg. The frequency of BPA procedures depended on the difficulty and number of the lesions. In the riociguat group, 1·0 mg riociguat was administered orally thrice daily. When the systolic blood pressure was maintained at 95 mm Hg or higher, the dose was increased by 0·5 mg every 2 weeks up to a maximum of 2·5 mg thrice daily; dose adjustment was completed within 4 months of the date of the first dose. The primary endpoint was change in mean pulmonary arterial pressure from baseline to 12 months, measured in the full analysis set (patients who were enrolled and randomly assigned to one of the study treatments, and had at least one assessment after randomisation). BPA-related complications and indices related to clinical worsening were recorded throughout the study period. Adverse events were recorded throughout the study period and evaluated in the safety analysis set (patients who were enrolled and randomely assigned to one of the study treatments, and had received part of or all the study treatments). This trial is registered in the Japan Registry of Clinical Trials (jRCT; jRCTs031180239) and is completed.

FINDINGS

Between Jan 8, 2016, and Oct 31, 2019, 61 patients with inoperable CTEPH were enrolled and randomly assigned to BPA (n=32) or riociguat (n=29). Patients in the BPA group underwent an average of 4·7 (SD 1·6) BPA procedures. In the riociguat group, the mean maintenance dose was 7·0 (SD 1·0) mg/day at 12 months. At 12 months, mean pulmonary arterial pressure had improved by -16·3 (SE 1·6) mm Hg in the BPA group and -7·0 (1·5) mm Hg in the riociguat group (group difference -9·3 mm Hg [95% CI -12·7 to -5·9]; p&lt;0·0001). A case of clinical worsening of pulmonary hypertension occurred in the riociguat group, whereas none occurred in the BPA group. The most common adverse event was haemosputum, haemoptysis, or pulmonary haemorrhage, affecting 14 patients (44%) in the BPA group and one (4%) in the riociguat group. In 147 BPA procedures done in 31 patients, BPA-related complications were observed in 17 procedures (12%) in eight patients (26%).

INTERPRETATION

Compared with riociguat, BPA was associated with a greater improvement in mean pulmonary arterial pressure in patients with inoperable CTEPH at 12 months, although procedure-related complications were reported. These findings support BPA as a reasonable option for inoperable CTEPH in centres with experienced BPA operators, with attention to procedure-related complications.

FUNDING

Bayer Yakuhin.

TRANSLATION

For the Japanese translation of the abstract see Supplementary Materials section.

Prevalence of Mental Disorders in Patients With Chronic Thromboembolic Pulmonary Hypertension

OBJECTIVE

Pulmonary hypertension (PH) is a chronic and progressive pulmonary vascular disease resulting in symptoms such as shortness of breath and fatigue and leading to death from right heart failure if not adequately treated. Chronic thromboembolic pulmonary hypertension (CTEPH) is a subgroup of PH characterized by obstruction or occlusion of pulmonary arteries by post-embolic fibrotic material. To date, few studies examined symptoms of depression and anxiety in patients with CTEPH, showing depression levels as high as 37.5%. However, none of the former studies used structured expert interviews.

METHODS

Mental disorders were diagnosed using the Structured Clinical Interview for DSM-5 (SCID). The prevalence of mental disorders in patients with CTEPH were compared to the prevalence in patients with pulmonary arterial hypertension (PAH) and the general German population. Quality of life (QoL) was measured with World Health Organization (WHO) Quality of Life questionnaire (short form). Factors associated with QoL were analyzed with linear regression and the diagnostic value of the Hospital Anxiety and Depression Scale (HADS) was evaluated using receiver operating characteristics (ROC) curve analysis.

RESULTS

Hundred and seven patients with CTEPH were included. Almost one-third of the patients (31.8%) had current psychological disorders. Panic disorder (8.4%), specific phobia (8.4%), and major depressive disorder (6.5%) were the most prevalent mental illnesses. The prevalence of panic disorders was higher in CTEPH compared to the German population while major depressive disorder was fewer in CTEPH compared to PAH. The presence of mental disorders had a major impact on QoL. Hospital Anxiety and Depression Scale discriminated depression and panic disorder reliably.

CONCLUSION

Mental disorders are common in patients with CTEPH and associated with an impaired QoL. The HADS may be a useful screening tool for panic and depression disorders in patients with CTEPH. Further research on therapeutic strategies targeting mental disorders in patients with CTEPH is needed.

Factors related to instrumental activities of daily living in persons with chronic thromboembolic pulmonary hypertension

Instrumental activities of daily living (IADL) are significantly related to quality of life and mortality among individuals with heart disease. However, few reports have examined IADL in persons with chronic thromboembolic pulmonary hypertension (CTEPH). The aim of this study was to clarify factors related to IADL in persons with CTEPH. This retrospective, observational study enrolled 163 persons with CTEPH (mean ± standard deviation age = 65 ± 13 years; 68% female) admitted to the Department of Cardiology at Keio University Hospital between January 2015 and July 2019. The Frenchay Activities Index (FAI) was used to assess IADL. Age, sex, body mass index, World Health Organization functional class (WHO-FC), cardiac function (mean pulmonary arterial pressure, mean right atrial pressure, pulmonary capillary wedge pressure, and cardiac index), pulmonary function (percentage vital capacity, percentage forced expiratory volume in 1 s, diffusion capacity of carbon monoxide (DLCO)/alveolar volume (VA)), physical function (knee extension strength and walking speed), and 6-min walking distance (6MWD) were assessed. Multiple regression analysis was performed to identify factors significantly associated with FAI. Mean FAI was 25 ± 8. Univariate analysis showed that sex, WHO-FC, DLCO/VA, walking speed, and 6MWD were correlated with FAI. Multiple regression analysis showed that 6MWD (sβ = 0.338, 95% CI 0.014–0.034, p < .001), sex (sβ = 0.268, 95% CI 2.238–7.165, p < .001), and DLCO/VA (sβ = 0.257, 95% CI 1.011–3.528, p < .001) were significantly correlated with FAI (R² = 0.261). IADL were associated with exercise tolerance, sex, and DLCO/VA in persons with CTEPH. In the future, more details of IADL are expected to be clarified by analyzing individual components of IADL and investigating social background characteristics, including living environment.

Chronic thromboembolic pulmonary hypertension: a review

Chronic thromboembolic pulmonary hypertension (CTEPH) is a unique form of pulmonary hypertension resulting from obstruction of the pulmonary artery by fibrotic thromboembolic material, usually initiated by recurrent or incomplete resolution of pulmonary embolism. This distinct form of pulmonary hypertension is classified under Group 4 of the World Health Organization classification. Further investigations are usually initiated, with transthoracic echocardiography followed by right heart catheterisation and pulmonary angiography as the gold standard. Definitive treatment is usually in the form of surgical pulmonary endarterectomy. Inoperable CTEPH is medically treated with pharmacological agents such as phosphodiesterase Type 5 inhibitors, endothelin receptor antagonists, soluble guanylate cyclase stimulators and prostacyclin. Recent developments have made balloon pulmonary angioplasty a viable option as well.

Efficacy and safety of balloon pulmonary angioplasty for residual pulmonary hypertension after pulmonary endarterectomy

BACKGROUND

Pulmonary endarterectomy (PEA) is the standard treatment for chronic thromboembolic pulmonary hypertension (CTEPH), although some patients may experience residual pulmonary hypertension (PH). It is unclear whether balloon pulmonary angioplasty (BPA) is effective for residual PH after PEA. This study aimed to compare the BPA outcomes between patients with residual PH after PEA and those with inoperable CTEPH.

METHODS

This retrospective study compared BPA for residual PH after PEA (25 patients, 101 BPA sessions) and BPA alone for inoperable CTEPH (21 patients, 89 BPA sessions). All patients underwent right heart catheterisation and functional and laboratory tests before PEA or before and after BPA.

RESULTS

There was no difference in the number of BPA sessions per patient (4.0 ± 1.9 vs. 4.2 ± 1.9, p = 0.671). No significant differences were observed with respect to the mean pulmonary artery pressure (23.6 ± 9.1 vs. 21.9 ± 5.7 mmHg, p = 0.44), pulmonary vascular resistance (3.7 ± 0.5 vs. 2.8 ± 1.2 Wood units, p = 0.14), 6-min walking distance (392.1 ± 117.7 vs. 452.4 ± 90.1 m, p = 0.096), and World Health Organization functional class (I/II/III/IV: 14/11/0/0 vs. 9/12/0/0, p = 0.375). Severe haemoptysis requiring embolisation was more common in the PH after PEA group (16.0% vs. 5.4%, p = 0.018). However, no patients required mechanical ventilation or extracorporeal membrane oxygenation, and there were no procedural deaths.

CONCLUSION

Although BPA might be effective for residual PH after PEA, it was associated with a high rate of haemoptysis.

Effect of Living Environment Factors on Quality of Life in Patients With Chronic Thromboembolic Pulmonary Hypertension After Completion of Balloon Pulmonary Angioplasty - A Cross-Sectional Study

Background: This study investigated factors related to quality of life (QoL) in patients with chronic thromboembolic pulmonary hypertension who completed balloon pulmonary angioplasty (BPA).

Methods and Results: Patient QoL and living environment after BPA were evaluated prospectively using the 5-level EQ-5D questionnaire and International Physical Activity Questionnaire Environmental Module (IPAQ-E), respectively. Patients were mailed copies of both surveys. In addition, we reviewed patient charts and collected retrospective clinical data. Relationship between the clinical data and QoL and environmental living factors were investigated. Of the 33 subjects mailed the surveys, sufficient responses were obtained from 22 (71%). Spearman’s rank correlation coefficient showed that psychiatric disorders (r=−0.6865, P<0.01) and IPAQ-E Question 5 (r=0.5192, P=0.02), Question 6 (r=0.5265, P=0.02), and Question 13 (r=0.4552, P=0.04) were significantly correlated with EQ-5D scores after BPA.

Conclusions: A living environment that was difficult to walk around was associated with a worse QoL. A multidisciplinary approach will be required to improve QoL even after completion of BPA treatment.

Patient Journey and Disease-Related Burden in Japanese Patients With Chronic Thromboembolic Pulmonary Hypertension: A Mixed Methods Study

BACKGROUND

Understanding patient journey and burden of disease in patients with chronic thromboembolic pulmonary hypertension (CTEPH) helps improve diagnostic and treatment processes.

OBJECTIVES

This study aimed to explore patient journey from time of disease onset to a definitive diagnosis and disease burden in Japanese patients with CTEPH.

METHODS

A mixed-methods study exploring patient journey and disease burden of 33 Japanese patients with a definitive diagnosis of CTEPH. The patients from 2 university hospitals underwent semistructured interviews. Data were transcribed into verbatim records, and 2 independent researchers conducted thematic analyses. Data concerning patient journey were also analyzed quantitatively with supplementary use of medical records.

RESULTS

Median times from initial onset of symptoms to a confirmed diagnosis and first visitation to a medical institution to a definitive diagnosis of CTEPH were 32 and 20 months, respectively. Thematic analyses found that, for patients, reasons for delay in seeking initial consultations included misattribution of symptoms to aging or lack of physical strength. For healthcare providers, reasons for delays in diagnosis included poor recognition of CTEPH and difficulty in recalling the disease as a differential diagnosis. Burdens of CTEPH were caused by physical symptoms, and mental and social issues, including restriction of daily activities owing to oxygen therapy, disappointment with the intractable nature of the disease, poor understanding of the disease by other people, and lack of social networks.

CONCLUSIONS

This study highlighted physical, mental, and social burdens in patients with CTEPH and possible missed opportunities in making the diagnosis of CTEPH during the patient journey. Increasing disease awareness in healthcare providers and networking among patients may contribute to better patient care.

Role of soluble guanylyl cyclase in renal afferent and efferent arterioles

Renal arteriolar tone depends considerably on the dilatory action of nitric oxide (NO) via activation of soluble guanylyl cyclase (sGC) and cGMP action. NO deficiency and hypoxia/reoxygenation are important pathophysiological factors in the development of acute kidney injury. It was hypothesized that the NO-sGC-cGMP system functions differently in renal afferent arterioles (AA) compared with efferent arterioles (EA) and that the sGC activator cinaciguat differentially dilates these arterioles. Experiments were performed in isolated, perfused mouse glomerular arterioles. Hypoxia (0.1% oxygen) was achieved by using a hypoxia chamber. Phosphodiesterase 5 (PDE5) and sGC subunits were considerably expressed on the mRNA level in AA. PDE5 inhibition with sildenafil, which blocks cGMP degradation, diminished the responses to ANG II bolus application in AA, but not significantly in EA. Vasodilation induced by sildenafil in ANG II-preconstricted vessels was stronger in EA than AA. Cinaciguat, an NO- and heme-independent sGC activator, dilated EA more strongly than AA after N^G-nitro-l-arginine methyl ester (l-NAME; NO synthase inhibitor) treatment and preconstriction with ANG II. Cinaciguat-induced dilatation of l-NAME-pretreated and ANG II-preconstricted arterioles was similar to controls without l-NAME treatment. Cinaciguat also induced dilatation in iodinated contrast medium treated AA. Furthermore, it dilated EA, but not AA, after hypoxia/reoxygenation. The results reveal an important role of the NO-sGC-cGMP system for renal dilatation and that EA have a more potent sGC activated dilatory system. Furthermore, AA seem to be more sensitive to hypoxia/reoxygenation than EA under these experimental conditions.

Identification of the Novel Variants in Patients With Chronic Thromboembolic Pulmonary Hypertension

Background Although chronic thromboembolic pulmonary hypertension (CTEPH) and acute pulmonary embolism (APE) share some clinical manifestations, a limited proportion of patients with CTEPH have a history of APE. Moreover, in histopathologic studies, it has been revealed that pulmonary vasculature lesions similar to pulmonary arterial hypertension existed in patients with CTEPH. Thus, it remains unknown whether these 3 disorders also share genetic backgrounds. Methods and Results Whole exome screening was performed with DNA isolated from 51 unrelated patients with CTEPH of Japanese ancestry. The frequency of genetic variants associated with pulmonary arterial hypertension or APE in patients with CTEPH was compared with those in the integrative Japanese Genome Variation Database 3.5KJPN. Whole exome screening analysis showed 17 049 nonsynonymous variants in patients with CTEPH. Although we found 6 nonsynonymous variants that are associated with APE in patients with CTEPH, there was no nonsynonymous variant associated with pulmonary arterial hypertension. Patients with CTEPH with a history of APE had nonsynonymous variants of F5, which encodes factor V. In contrast, patients with CTEPH without a history of APE had a nonsynonymous variant of THBD, which encodes thrombomodulin. Moreover, thrombin-activatable fibrinolysis inhibitor, which is one of the pathogenic proteins in CTEPH, was significantly more activated in those who had the variants of THBD compared with those without it. Conclusions These results provide the first evidence that patients with CTEPH have some variants associated with APE, regardless of the presence or absence of a history of APE. Furthermore, the variants might be different between patients with CTEPH with and without a history of APE.

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.

Involvement of pulmonary arteriopathy in the development and severity of reperfusion pulmonary edema after pulmonary endarterectomy

Reperfusion pulmonary edema (RPE) is a common complication after pulmonary endarterectomy (PEA) in patients with chronic thromboembolic pulmonary hypertension (CTEPH). However, the precise mechanisms underlying the development of RPE remain unclear. To evaluate the effects of pulmonary vasculopathy on RPE, the severity of the pulmonary arteriopathies and venopathies of lung tissues biopsied during PEA were pathologically quantified in 33 CTEPH patients. The severity of RPE was classified from grade 0 (no RPE) to 4 (death due to RPE) based on the arterial oxygen tension/inspiratory oxygen fraction (P/F ratio) and necessity of respiratory management. Among the 33 patients (27 women; mean age = 63.3 years), 17 (51.5%) patients developed RPE. The severity of pulmonary arteriopathy (obstruction ratio) correlated with the grade of RPE (r = 0.576, P = 0.0005). The obstruction ratio also correlated with the P/F ratio (r = −0.543, P = 0.001) and the perioperative mean pulmonary arterial pressure (r = 0.445, P = 0.009). Multivariate logistic regression analysis revealed that the obstruction ratio was a significant independent determinant for the development of RPE (odds ratio = 15.7; 95% confidence interval = 2.29–108.00, P = 0.005). In conclusion, pulmonary arteriopathy could be a determinant of the development and severity of RPE after PEA.

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.

Gender Differences Among Patients With Acute Pulmonary Embolism

Gender differences in patients with acute pulmonary embolism (APE) remain unclear and controversial. We aimed to understand the gender differences in patients with APE treated in the cardiovascular care units. The registry database of 1,428 patients with APE treated at the Tokyo cardiovascular care unit Network institutions from 2010 to 2014 was retrieved for analysis. In all, 795 women (55.7%) and 633 men (44.3%) were included in this study. The women were older than men (68.0 ± 16.1 vs 60.9 ± 15.6 years, p < 0.0001). Compared with men, women had more complaints of dyspnea and disturbed consciousness, lesser complaints of leg symptoms, and chest pain. Pulmonary arterial systolic pressure (51.5 ± 22.2 mm Hg vs 47.4 ± 22.4 mm Hg, p = 0.012) and the serum B-type natriuretic peptide level (180.4 [50.7 to 526.1] pg/ml vs 107.0 [25.0 to 306.8] pg/ml, p < 0.0001) on admission, was higher in women than in men. Severe cases with massive embolism were seen more in women compared with men (14.6% vs 9.2%, p = 0.0002). The use of inferior vena cava filters were lower in women than in men (31.9% vs 37.3%, p = 0.029). Furthermore, 30-day PE-related mortality was higher in women than in men significantly (5.0% vs 2.8%, p = 0.043). In conclusion, women APE patients were older with higher severity than men APE patients, resulting in poor prognosis.

Balloon pulmonary angioplasty for chronic thromboembolic pulmonary hypertension: A systematic review

BACKGROUND

Balloon pulmonary angioplasty (BPA) has been performed for inoperable chronic thromboembolic pulmonary hypertension (CTEPH) or residual pulmonary hypertension after pulmonary endarterectomy (PEA). We performed a systematic review to assess the efficacy and safety of BPA, especially compared to medical treatment or PEA.

METHODS

We reviewed all studies investigating pre- and post-treatment pulmonary hemodynamics, mortality, or complications from three electronic databases (PubMed, Cochrane Library, Japan Medical Abstracts Society) prior to February 2017. From 26 studies retrieved, we selected 13 studies (493 patients): the 10 most recent ones including complete data from each institution, one study of residual pulmonary hypertension, and two studies comparing BPA with medical treatment or PEA.

RESULTS

No randomized controlled or prospective controlled studies comparing BPA with medical treatment or PEA were reported. The early mortality of BPA ranged from 0% to 14.3%; lung injury occurred in 7.0% to 31.4% (average sessions, 2.5-6.6). Mean pulmonary arterial pressure decreased from 39.4-56 to 20.9-36 mm Hg, and the 6-min walk distance increased from 191-405 to 359-501 m. The 2-year mortality of 80 patients undergoing BPA was significantly lower compared to 68 patients receiving medical treatment (1.3% vs. 13.2%); the risk ratio was 0.14 (95% confidence interval: 0.03-0.76). No significant difference was observed in the 2-year mortality between BPA (n=97) and PEA (n=63) patients.

CONCLUSIONS

This systematic review suggests that BPA improves hemodynamics, has acceptable early mortality, and may improve long-term survival compared with medical treatment in inoperable CTEPH patients.

Long-Term Outcome of Chronic Thromboembolic Pulmonary Hypertension at a Single Japanese Pulmonary Endarterectomy Center

BACKGROUND

Several new treatments for chronic thromboembolic pulmonary hypertension (CTEPH) have appeared in recent years, which have led to changes in the treatment algorithm. Changes in survival rates and prognostic factors, however, have not been estimated so far.Methods and Results:Two hundred and eighty patients were diagnosed with CTEPH at Chiba University Hospital between June 1986 and June 2016. Survival rate was investigated by date of treatment initiation (group 1, 1986-1998; group 2, 1999-2008; group 3, 2009-2016). Survival rates were also evaluated by treatment strategy: balloon pulmonary angioplasty (BPA), pulmonary endarterectomy (PEA), and medical treatment. Group 3 had significantly better disease-specific survival than groups 1 and 2 (5-year survival: 91.9% vs. 67.1%, 77.0%, respectively). For the non-PEA (BPA+medication) strategy, group 3 had better disease-specific survival than groups 1 and 2 (5-year survival: 94.9% vs. 54.6%, 74.2%, respectively). The PEA strategy had significantly better survival than the medication strategy in groups 1 and 2, whereas no difference was observed between the BPA, PEA, and medication strategies in group 3.

CONCLUSIONS

Survival in CTEPH in the recent era has significantly improved, especially in non-PEA patients. BPA and selective pulmonary vasodilators could improve survival in the non-PEA group. In the present study, no difference in survival was found between PEA and non-PEA.

Sex-specific cardiopulmonary exercise testing indices to estimate the severity of inoperable chronic thromboembolic pulmonary hypertension

Background

Sex differences in chronic thromboembolic pulmonary hypertension (CTEPH) have been revealed in few studies. Although right heart catheterization (RHC) is the gold standard for clinical diagnosis and assessment of prognosis in pulmonary hypertension (PH), cardiopulmonary exercise testing (CPET) has been a more widely used assessment of functional capacity, disease severity, prognosis, and treatment response in PH. We hypothesized that the “sex-specific” CPET indices could estimate the severity of inoperable CTEPH.

Methods

Data were retrieved for 33 male (age, mean ± standard deviation [SD] =62.5±13.4 years) and 40 female (age, mean ± SD =56.3±11.8 years) patients with stable CTEPH who underwent both RHC and CPET at Shanghai Pulmonary Hospital from February 2010 to February 2016. Univariate and forward/backward multiple stepwise regression analysis was performed to assess the predictive value of CPET indices to hemodynamic parameters. Event-free survival was estimated using the Kaplan–Meier method and analyzed with the log-rank test. Cox proportional hazards models were performed to determine the independent event-free survival predictors.

Results

Numerous CPET parameters were different between male and female patients with CTEPH and the control group. There were no significant differences in both clinical variables and RHC parameters between male and female patients with CTEPH. O₂ pulse, workload, minute ventilation (VE), and end-tidal partial pressure of O₂ (P_ETO₂) at anaerobic threshold, as well as peak O₂ pulse, workload, VE, and nadir VE/CO₂ were significantly higher in male patients than in female patients (P<0.05). Only oxygen uptake efficiency plateau (OUEP) showed a significantly higher difference in female than male patients (P<0.05). In addition, several CPET indices correlated with hemodynamic parameters, especially pulmonary vascular resistance (PVR), which was distinctly different between the sexes. Nadir VE/CO₂ was an independent predictor of PVR in male patients with CTEPH, whereas OUEP was an independent predictor of PVR in female patients with CTEPH.

Conclusion

Even after confounding for age and body mass index, different CPET measurements of gas exchange efficiency correlated with PVR differently between male and female patients. This potentially could be used to estimate the severity of CTEPH.

Mosaic attenuation pattern in non-contrast computed tomography for the assessment of pulmonary perfusion in chronic thromboembolic pulmonary hypertension

BACKGROUND

Chronic thromboembolic pulmonary hypertension (CTEPH) is difficult to diagnose as patients rarely present with specific symptoms. However, a mosaic attenuation pattern (MAP) in chest computed tomography (CT) suggests CTEPH. Areas of increased attenuation are not always visible using default CT settings for the lung. Thus, we examined the utility of non-contrast CT imaging with new settings focusing on MAP (CT_Mosaic) for the assessment of pulmonary perfusion in patients with CTEPH. The regional perfusion defects visualized using CT_Mosaic and single-photon-emission CT with fusion of CT images (SPECT/CT) were compared.

METHODS

Twenty-seven patients with CTEPH (20 women; aged 62.8±7.9 years) underwent imaging with non-contrast CT and SPECT/CT. We converted non-contrast mediastinal CT images into various CT window settings to identify the MAP, and the CT window setting that could most easily identify the MAP was defined as CT_Mosaic. We then scored and compared lung segments depending on the degree of perfusion on CT_Mosaic and SPECT/CT.

RESULTS

CT_Mosaic was identified as the CT window setting in which the window level was -800 Hounsfield units (HU), and the window width was 200 HU. Using CT_Mosaic, MAP was detected in 366 of 486 segments (75.3%). The agreement between CT_Mosaic and perfusion defects on SPECT/CT was 84.9%. Weighted kappa statistics demonstrated a good agreement between the two examinations (κ=0.605, 95% confidence interval, 0.502-0.707).

CONCLUSIONS

The CT_Mosaic setting can easily identify an MAP in CTEPH patients. Therefore, this may be useful as a simple and cost-effective evaluation method for blood distribution in patients with CTEPH.

Balloon Pulmonary Angioplasty in Chronic Thromboembolic Pulmonary Hypertension: New Horizons in the Interventional Management of Pulmonary Embolism

Chronic thromboembolic pulmonary hypertension (CTEPH) is an underdiagnosed potential complication of acute or recurrent pulmonary thromboembolic disease. Multiple studies suggest that up to 5% of patients with acute pulmonary thromboembolic disease go on to develop CTEPH. The prognosis of untreated CTEPH is poor, but advances in medical and surgical treatments over the past few decades have improved patient outcomes. The gold standard and curative treatment for CTEPH is pulmonary endarterectomy; however, some patients are inoperable and others who have undergone pulmonary endarterectomy experience persistent or recurrent pulmonary hypertension despite medical therapy. In recent years, balloon pulmonary angioplasty has emerged as a primary and adjunctive treatment for these CTEPH patients at expert or specialized centers. This review outlines an approach to balloon pulmonary angioplasty for CTEPH, including clinical presentation and evaluation; patient selection and indications; treatment planning; equipment and technique; overcoming technical challenges; recognition and management of complications; postprocedural care and clinical follow-up; and expected outcomes.

The anticoagulant effects of warfarin and the bleeding risk associated with its use in patients with chronic thromboembolic pulmonary hypertension at a specialist center in Japan: a retrospective cohort study

Patients with chronic thromboembolic pulmonary hypertension (CTEPH) require lifelong anticoagulation therapy. However, the bleeding risk and recurrence of venous thromboembolism (VTE) in CTEPH patients who are administered warfarin have not been adequately evaluated. The purpose of this study was to evaluate the risk of clinically relevant bleeding, recurrent VTE, and clinical worsening in patients with CTEPH who were administered warfarin.

The clinical records of 72 patients with CTEPH who regularly visited our institution and were administered warfarin were retrospectively reviewed between 1 January 2011 and 31 December 2015. We investigated the incidence of clinically relevant bleeding events, recurrent VTE, and hospitalization for the deterioration of pulmonary hypertension or right heart failure (RHF) during the observation period.

The mean observation period for the 72 patients was 3.60 ± 1.60 person-years. Clinically relevant bleeding, RHF, and recurrent VTE occurred in 21 (29.2%), eight (11.1%), and three (4.2%) of 72 patients, respectively, and the incidence rates for these events were 8.1%/person-year, 3.1%/person-year, and 1.2%/person-year, respectively. The incidence rates for the major and non-major bleeding events were 5.0%/person-year and 3.9%/person-year, respectively. The incidence of clinically relevant bleeding events was 20.8%/person-year during medical treatment with a soluble guanylate cyclase stimulator. One of 35 patients (2.9%) during the post-pulmonary endarterectomy period experienced hemoptysis during observation period (> 6 months after pulmonary endarterectomy). No bleeding events occurred during the post-balloon pulmonary angioplasty period.

In conclusion, warfarin effectively prevents VTE recurrence in CTEPH patients, but its effects may be associated with a considerable bleeding risk.

The Development of Marked Collateral Circulation due to Inferior Vena Cava Filter Occlusion in a Patient with Chronic Thromboembolic Pulmonary Hypertension Complicated with Anti-phospholipid Syndrome

A 30-year-old Japanese man was diagnosed with chronic thromboembolic pulmonary hypertension (CTEPH) with lupus anticoagulants (LAs) in 2003. He underwent pulmonary endarterectomy after the placement of an inferior vena cava filter (IVCF) in 2004, and treatment with warfarin was continued. In 2014, IVCF occlusion and marked collateral circulation were noted during an examination for transient dyspnea; however, his warfarin level was within the therapeutic range for 88.9% of the time from 2003 to 2014. We herein report a rare case of CTEPH and LAs with IVCF occlusion; in such cases, intense treatment may be required.

Severe Pulmonary Arteriopathy Is Associated with Persistent Hypoxemia after Pulmonary Endarterectomy in Chronic Thromboembolic Pulmonary Hypertension

BACKGROUND

Chronic thromboembolic pulmonary hypertension (CTEPH) is characterized by occlusion of pulmonary arteries by organized chronic thrombi. Persistent hypoxemia and residual pulmonary hypertension (PH) following successful pulmonary endarterectomy (PEA) are clinically important problems; however, the underlying mechanisms remain unclear. We have previously reported that residual PH is closely related to severe pulmonary vascular remodeling and hypothesize that this arteriopathy might also be involved in impaired gas exchange. The purpose of this study was to evaluate the association between hypoxemia and pulmonary arteriopathy after PEA.

METHODS AND RESULTS

Between December 2011 and November 2014, 23 CTEPH patients underwent PEA and lung biopsy. The extent of pulmonary arteriopathy was quantified pathologically in lung biopsy specimens. We then analyzed the relationship between the severity of pulmonary arteriopathy and gas exchange after PEA. We observed that the severity of pulmonary arteriopathy was negatively correlated with postoperative and follow-up PaO2 (postoperative PaO2: r = -0.73, p = 0.0004; follow-up PaO2: r = -0.66, p = 0.001), but not with preoperative PaO2 (r = -0.373, p = 0.08). Multivariate analysis revealed that the obstruction ratio and patient age were determinants of PaO2 one month after PEA (R2 = 0.651, p = 0.00009). Furthermore, the obstruction ratio and improvement of pulmonary vascular resistance were determinants of PaO2 at follow-up (R2 = 0.545, p = 0.0002). Severe pulmonary arteriopathy might increase the alveolar-arterial oxygen difference and impair diffusion capacity, resulting in hypoxemia following PEA.

CONCLUSION

The severity of pulmonary arteriopathy was closely associated with postoperative and follow-up hypoxemia.

Balloon pulmonary angioplasty: applicability of C-Arm CT for procedure guidance

PURPOSE

To investigate the feasibility of and compare two C-Arm CT (CACT) guidance methods during balloon pulmonary angioplasty (BPA).

MATERIAL AND METHODS

Forty-two BPAs [27 CTEPH patients (nine males, 70 ± 14y)] targeting 143 pulmonary arteries were included. Twenty-two BPAs were guided by contrast-enhanced CACT acquired immediately before BPA (G3D). In another 20 BPAs (G2D), two orthogonal fluoroscopy images of the chest where acquired to compute a registration of a previously acquired CACT. Volume rendering-based graphic representations (VRT guidance) were generated indicating the origin and course of the vessels. Based on VRT guidance, the intervention was planned. Procedure durations and radiation exposure data were compared between the two groups (Wilcoxon test).

RESULTS

The overall intervention time was approximately 2 h in both groups (p = 0.31). BPA was successfully performed in G3D 91 % and G2D 94 %. No significant difference was found concerning the mean dose area product (DAP) related to fluoroscopy (p = 0.38), while DAP related to DSA was slightly higher in G3D (p = 0.048). Overall, DAP was significantly higher in G3D (p = 0.002).

CONCLUSIONS

The use of CACT for procedure guidance in patients undergoing BPA is feasible and accurate. Image fusion of a pre-acquired CACT can be used to decrease radiation exposure due to multiple BPA sessions.

KEY POINTS

• BPA guidance by CACT overlay is feasible and safe. • 2D3D image fusion for BPA guidance is accurate. • Image fusion can reduce patient radiation dose due to repeated BPA sessions.

Pulmonary Artery Imaging in Patients with Chronic Thromboembolic Pulmonary Hypertension: Comparison of Cone-Beam CT and 64-Row Multidetector CT

PURPOSE

To compare the depiction of pulmonary arteries in pulmonary arterial catheter-based contrast-enhanced cone-beam CT with peripheral intravenous contrast-enhanced multidetector CT in patients with suspected chronic thromboembolic pulmonary hypertension.

MATERIAL AND METHODS

In 20 patients (15 men and 5 women, 63.4 y ± 16.3), cone-beam CT using a catheter placed in the main pulmonary artery and 64-row multidetector CT using an appropriate venous access were performed. Contrast enhancement was measured in the main pulmonary artery, the right and left pulmonary arteries, and the left atrium. The amount of peripheral vessel conspicuity adjacent to the pleural surface (distance from vessel-to pleura) was measured. Two readers (R1, R2) independently evaluated the pulmonary arteries for image quality and pathologic findings in both modalities.

RESULTS

Contrast density was higher in the main pulmonary artery and right and left pulmonary arteries (P < .002) and lower in the left atrium (P = .001) on cone-beam CT. The smallest distance between clearly delineated vessels and the pleura was significantly lower on cone-beam CT images (P < .0001). Interobserver agreement was good for cone-beam CT (κ = 0.79) and multidetector CT (κ = 0.78), whereas intermodality agreement was moderate (R1, κ = 0.60; R2, κ = 0.59). Both readers detected more weblike stenoses with cone-beam CT (76; 22%) compared with multidetector CT (25; 7%).

CONCLUSIONS

Cone-beam CT shows improved contrast between pulmonary arteries and the left atrium and allows a more detailed depiction of the pulmonary arteries.

Chronic Thromboembolic Pulmonary Hypertension: Experience from a Single Center in Mexico

INTRODUCTION

Chronic thromboembolic pulmonary hypertension (CTEPH) is characterized by precapillary pulmonary hypertension secondary to vaso-occlusive pulmonary vasculopathy and is classified as Pulmonary Hypertension Group 4. The aim of this study is to report the clinical experience of CTEPH in Mexico.

METHODS

Consecutive patients diagnosed with CTEPH were identified from the Registro de Pacientes con Hipertension Pulmonar del Instituto de Seguridad y Servicio Social de los Trabajadores del Estado (REPHPISSSTE) registry between January 2009 and February 2014. Right heart catheterization was not routinely performed prior to August 2010 in the work-up of CTEPH.

RESULTS

We identified 50 patients with CTEPH; their median age was 63 years and 58 % were female. Patients had multiple associated co-morbidities and moderate hemodynamic impairment. All patients were treated with anticoagulation. Despite surgical evaluation for pulmonary endarterectomy (PEA), only one patient underwent PEA given the lack of infrastructure for post-operative care and lack of insurance for this procedure. Most of the patients were treated with sildenafil, bosentan, or both, with increasing use of rivaroxaban and sildenafil in recent years. The overall survival of the cohort was similar to that reported in other international registries, despite the limitations of care imposed by drug availability and surgical feasibility.

CONCLUSION

This is the first report on the CTEPH experience in Mexico. It highlights the similarity of patients in the REPHPISSSTE registry to those in international registries as well as the challenges that clinicians face in a resource-limited setting.

Evaluation of the Microcirculation in Chronic Thromboembolic Pulmonary Hypertension Patients: The Impact of Pulmonary Arterial Remodeling on Postoperative and Follow-Up Pulmonary Arterial Pressure and Vascular Resistance

Background

Chronic thromboembolic pulmonary hypertension (CTEPH) is generally recognized to be caused by persistent organized thrombi that occlude the pulmonary arteries. The aim of this study was to investigate the characteristics of small vessel remodeling and its impact on the hemodynamics in CTEPH patients.

Methods and Results

Hemodynamic data were obtained from right heart catheterization in 17 CTEPH patients before pulmonary endarterectomy (PEA). Lung tissue specimens were obtained at the time of PEA. Pathological observations and evaluation of quantitative changes in pulmonary muscular arteries and veins were performed using light microscopy on 423 slides in 17 patients. The relationship between the results and the hemodynamics of CTEPH was investigated. Pulmonary arteriopathy and venopathy were recognized in most cases, although no plexiform lesions and no capillary-hemangiomatosis-like lesions were detected in any of the specimens. The severity of pulmonary arteriopathy was correlated with pulmonary vascular resistance (PVR) in the postoperative and follow-up periods. The PVR and mean pulmonary arterial pressure were significantly higher in the high-obstruction group than in the low-obstruction group. The findings in pulmonary venopathy were similar to the findings seen in pulmonary veno-occlusive disease in some cases, although severe venopathy was only observed in a portion of the pulmonary veins. There was a significant correlation between the extent of pulmonary arteriopathy and venopathy, although an effect of pulmonary venopathy to hemodynamics, including pulmonary arterial wedged pressure (PAWP), could not be identified.

Conclusion

The vascular remodeling of the pulmonary muscular arteries was closely associated with the hemodynamics of CTEPH. Severe pulmonary arteriopathy might be related to residual pulmonary hypertension after PEA. Those altered pulmonary arteries might be a new target for the persistent PH after the operation.

Chronic thromboembolic pulmonary arterial hypertension: a review of the literature and novel therapeutic approaches

Chronic thromboembolic pulmonary hypertension is defined as pulmonary hypertension (PH) caused by single or recurrent pulmonary emboli and is characterized by chronic obstruction of the pulmonary arteries leading to increased vascular resistance and PH. Also, progressive remodeling may occur in occluded and nonoccluded territories. Better understanding of the underlying mechanisms and risk factors could improve diagnosis and allow appropriate interventions. Pulmonary endarterectomy is an established approach and is considered the definitive treatment for chronic PH, resulting from thromboembolic disease. Furthermore, percutaneous transluminal pulmonary angioplasty is technically feasible, especially for those with peripheral-type of the disease. In addition, several agents, including prostanoids, endothelin receptor antagonists and phosphodiesterase type-5 inhibitors, have been tested in selected patients yielding promising results. Several novel agents are under investigation, and extensive research is currently in progress aiming to resolve uncertainties in the understanding and treatment of the disease.

Comparison of C-arm Computed Tomography and Digital Subtraction Angiography in Patients with Chronic Thromboembolic Pulmonary Hypertension

PURPOSE

To assess the feasibility and diagnostic performance of contrast-enhanced, C-arm computed tomography (CACT) of the pulmonary arteries compared to digital subtraction angiography (DSA) in patients suffering from chronic thromboembolic pulmonary hypertension (CTEPH).

MATERIALS

Fifty-two patients with CTEPH underwent ECG-gated DSA and contrast-enhanced CACT. Two readers (R1, R2) independently evaluated pulmonary artery segments and their sub-segmental branching using DSA and CACT for optimal image quality. Afterwards, the diagnostic findings, i.e., intraluminal filling defects, stenosis, and occlusion, were compared. Inter-modality and inter-observer agreement was calculated, and subsequently consensus reading was done and correlated to a reference standard representing the overall consensus of both modalities. Fisher's exact test and Cohen's Kappa were applied.

RESULTS

A total of 1352 pulmonary segments were evaluated, of which 1255 (92.8 %) on DSA and 1256 (92.9 %) on CACT were rated to be fully diagnostic. The main causes of the non-diagnostic image quality were motion artifacts on CACT (R1:37, R2:78) and insufficient contrast enhancement on DSA (R1:59, R2:38). Inter-observer agreement was good for DSA (κ = 0.74) and CACT (κ = 0.75), while inter-modality agreement was moderate (R1: κ = 0.46, R2: κ = 0.47). Compared to the reference standard, the inter-modality agreement for CACT was excellent (κ = 0.96), whereas it was inferior for DSA (κ = 0.61) due to the higher number of abnormal consensus findings read as normal on DSA.

CONCLUSION

CACT of the pulmonary arteries is feasible and provides additional information to DSA. CACT has the potential to improve the diagnostic work-up of patients with CTEPH and may be particularly useful prior to surgical or interventional treatment.

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

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

Home-based pulmonary rehabilitation in patients with inoperable or residual chronic thromboembolic pulmonary hypertension: a preliminary study

BACKGROUND

Management of chronic thromboembolic pulmonary hypertension (CTEPH) has recently improved because of advances in pulmonary endarterectomy (PEA), balloon pulmonary angioplasty (BPA), and disease-targeted medications. However, patients with inoperable CTEPH or persistent pulmonary hypertension (PH) after these interventions continue to exhibit impaired exercise capacity and limited quality of life (QOL).

METHODS

Eight patients with inoperable or residual CTEPH (mean age, 64±12 years; WHO functional class II/III, 6/2; mean pulmonary artery pressure, 47±13 mmHg) in stable condition and receiving disease-targeted medications participated in a 12-week home-based pulmonary rehabilitation program (muscle strength training, respiratory exercises, and walking) with supervised hospital sessions from March 2012 to January 2014. Efficacy parameters were prospectively evaluated at baseline and at completion of the 12-week program.

RESULTS

After completion of the pulmonary rehabilitation program, the 6-minute walking distance (6MWD) (33.3±25.1 m), St. George׳s Respiratory Questionnaire activity score, quadriceps force, and 7-day physical activity level were significantly improved compared with baseline. All subjects completed the rehabilitation program. Although one patient experienced presyncope during the in-hospital exercise sessions, no other severe adverse events or complications of pulmonary rehabilitation were observed.

CONCLUSIONS

These findings suggest that home-based pulmonary rehabilitation with closely supervised sessions may safely improve exercise capacity, leg muscle strength, general activity in daily life and health-related QOL in CTEPH patients.