Evaluation of right and left heart mechanics in patients with chronic thromboembolic pulmonary hypertension before and after pulmonary thromboendarterectomy

Performance-based outcome measures for assessing physical capacity in patients with pulmonary embolism: A scoping review

INTRODUCTION

Up to 50 % of patients surviving a pulmonary embolism (PE) report persisting shortness of breath, reduced physical capacity and psychological distress. As the PE population is heterogeneous compared to other cardiovascular patient groups, outcome measures for assessing physical capacity traditionally used in cardiac populations may not be reliable for the PE population as a whole. This scoping review aims to 1) map performance-based outcome measures (PBOMs) used for assessing physical capacity in PE research, and 2) to report the psychometric properties of the identified PBOMs in a PE population.

METHODS

The review was conducted according to the Joanna Briggs Institute framework for scoping reviews and reported according to the PRISMA-Extension for Scoping Reviews guideline.

RESULTS

The systematic search of five databases identified 4585 studies, of which 243 studies met the inclusion criteria. Of these, 185 studies focused on a subgroup of patients with chronic thromboembolic pulmonary hypertension. Ten different PBOMs were identified in the included studies. The 6-minute walk test (6MWT) and cardiopulmonary exercise test (CPET) were the most commonly used, followed by the (Modified) Bruce protocol and Incremental Shuttle Walk test. No studies reported psychometric properties of any of the identified PBOMs in a PE population.

CONCLUSIONS

Publication of studies measuring physical capacity within PE populations has increased significantly over the past 5-10 years. Still, not one study was identified, reporting the validity, reliability, or responsiveness for any of the identified PBOMs in a PE population. This should be a priority for future research in the field.

Do Right Heart Hemodynamic Improvements Persist After Pulmonary Thromboendarterectomy?

The survival benefits of pulmonary thromboendarterectomy (PTE) for the treatment of chronic thromboembolic pulmonary hypertension have been well described. However, the significance of right heart hemodynamic changes and their impact on survival remains poorly understood. We sought to characterize the effects of these changes. We conducted a single center, retrospective review of 159 patients who underwent PTE between 1993 and 2015. Echocardiographic and right heart catheterization data were compared longitudinally before and after PTE in order to establish the extent of hemodynamic response to surgery. Kaplan Meier estimates were used to characterize patient survival over time. Univariable and multivariable Cox proportional hazards regression models were used to assess factors associated with long-term mortality. Among the 159 patients studied, 74 (46.5%) were male with a median age of 55 (IQR: 42-66). One-, 5-, 10-, and 15-year survival was 91.0% (95% CI: 86.6-95.6), 79.6% (73.5-86.3), 66.5% (59.2-74.7), and 56.2% (48.1-65.8). Of the 9 candidate risk factors that were evaluated, only advanced age and increased cardiopulmonary bypass time were found to be significantly associated with increased risk of mortality. Pre- and postsurgical echocardiographic imaging data, when available, revealed a median reduction in right ventricular systolic pressure of 29.0 mm Hg (P < 0.0001) and improvement of tricuspid regurgitation (P < 0.0001), both of which appeared to be sustained across long-term follow-up. Improvements in right heart hemodynamics and tricuspid valvular regurgitation persist on long term surveillance following PTE. While patient selection is often driven by the distribution of disease, close postoperative follow up may improve outcomes.

Correlation Between Perfusion Abnormalities Extent in Ventilation/Perfusion SPECT/CT with Hemodynamic Parameters in Patients with Chronic Thromboembolic Pulmonary Hypertension

Objectives

Chronic thromboembolic pulmonary hypertension (CTEPH) is a type of pulmonary hypertension with persistent pulmonary vascular obstruction and exercise intolerance, which may benefit from pulmonary endarterectomy (PEA). Ventilation/perfusion (V/Q) scan is the preferred screening test of CTEPH, which can be used to assess the anatomical extent of the disease. This study aimed to analyze the correlation between the extent of mismatched Q defects in V/Q single photon emission computed tomography/computed tomography (SPECT/CT) with preoperative clinical and hemodynamic parameters in patients with CTEPH.

Methods

A total of 102 patients with CTEPH prior to PEA having V/Q SPECT/CT scans were retrospectively reviewed. Age, gender, New York Heart Association classification, intraoperative right-sided heart catheterization (mPAP and PVR), and 6-minute walk test (6MWT) findings were obtained from clinical records of patients.

Results

Linear regression analysis showed a significant but weak correlation between the preoperative mPAP and PVR with the extent of mismatched Q defects in V/Q SPECT/CT (rs=0.09474 with p=0.0016 and rs=0.045 with p=0.045, respectively). No significant correlation was found between 6MWT and extent of mismatched Q defects in V/Q SPECT/CT (p>0.05).

Conclusion

A quantitative assessment of Q defects on V/Q SPECT/CT might provide information about hemodynamic parameters in patients with CTEPH.

Imaging in Chronic Thromboembolic Pulmonary Hypertension

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

Preliminary results from a nationwide adult cardiology perspective for pulmonary hypertension: RegiStry on clInical outcoMe and sUrvival in pulmonaRy hypertension Groups (SIMURG)

OBJECTIVE

The present study was designed to evaluate the characteristics of pulmonary hypertension (PH) and adult cardiology practice patterns for PH in our country.

METHODS

We evaluated preliminary survey data of 1501 patients with PH (females, 69%; age, 44.8±5.45) from 20 adult cardiology centers (AdCCs).

RESULTS

The average experience of AdCCs in diagnosing and treating patients with PH was 8.5±3.7 years. Pulmonary arterial hypertension (PAH) was the most frequent group (69%) followed by group 4 PH (19%), group 3 PH (8%), and combined pre- and post-capillary PH (4%). PAH associated with congenital heart disease (APAH-CHD) was the most frequent subgroup (47%) of PAH. Most of the patients' functional class (FC) at the time of diagnosis was III. The right heart catheterization (RHC) rate was 11.9±11.6 per month. Most frequently used vasoreactivity agent was intravenous adenosine (60%). All patients under targeted treatments were periodically for FC, six-minute walking test, and echo measures at 3-month intervals. AdCCs repeated RHC in case of clinical worsening (CW). The annual rate of hospitalization was 14.9±19.5. In-hospital use of intravenous iloprost reported from 16 AdCCs in CWs. Bosentan and ambrisentan, as monotreatment or combination treatment (CT), were noted in 845 and 28 patients, respectively, and inhaled iloprost, subcutaneous treprostinil, and intravenous epoprostenol were noted in 283, 30, and four patients, respectively. Bosentan was the first agent used for CT in all AdCCs and iloprost was the second. Routine use of antiaggregant, anticoagulant, and pneumococcal and influenza prophylaxis were restricted in only two AdCCs.

CONCLUSION

Our nationwide data illustrate the current status of PH regarding clinical characteristics and practice patterns.