Treatment of Vascular Injury During Balloon Pulmonary Angioplasty in Patients With Chronic Thromboembolic Pulmonary Hypertension

Background

Treatment strategy for vascular injury during balloon pulmonary angioplasty (BPA) in patients with chronic thromboembolic pulmonary hypertension (CTEPH) was uncertain.

Objectives

This study aimed to identify an optimal therapeutic strategy for vascular injury during BPA in patients with CTEPH.

Methods

This study reviewed 207 patients with CTEPH and 956 BPA procedures between November 1, 2012 and November 30, 2015. Patients who were diagnosed with vascular injury during BPA, which was defined as angiographic signs or sudden respiratory and hemodynamic defects were included in this study. The study investigated the safety and efficacy of the hierarchically systematic treatment strategy including gelatin sponge embolization (GSE).

Results

More than one-half of the 79 patients and 133 procedures with vascular injury were improved by general treatment with reversal of heparin and high-flow oxygen administration. The investigators performed conventional treatment of proximal vessel occlusion using a guiding or balloon catheter in 47 procedures (35%) in which the culprit vessels could be detected under patients' stable conditions. In 32 procedures (24%) without detected culprit lesions or improvement by conventional treatment, GSE could significantly improve patient condition. The treatment strategy obtained successful bailout in 98% of procedures with vascular injury. No patients who underwent GSE died within 30 days after the treatment. There was no significant difference in cumulative mortality rate (median follow-up: 6.6 years) between groups with or without GSE (15.6% vs 8.2%; adjusted HR: 1.47; 95% CI: 0.25-8.69; P = 0.67).

Conclusions

Treatment strategy including GSE would be promising for vascular injury during BPA in patients with CTEPH.

Pulmonary Hypertension Definition, Classification, and Epidemiology in Asia

Pulmonary hypertension (PH) is caused by a range of conditions and is important to recognize as it is associated with increased mortality. Pulmonary arterial hypertension refers to a group of PH subtypes affecting the distal pulmonary arteries for which effective treatment is available. The hemodynamic definition of pulmonary arterial hypertension has recently changed which may lead to greater case recognition and earlier treatment. The prevalence of specific PH etiologies may differ depending on geographic region. PH caused by left heart disease is the most common cause of PH worldwide. In Asia, there is greater proportion of congenital heart disease- and connective tissue disease- (especially systemic lupus erythematosus) related PH relative to the West. This review summarizes the definition, classification, and epidemiology of PH as it pertains to Asia.

Balloon Pulmonary Angioplasty for Chronic Thromboembolic Pulmonary Hypertension: Initial Single-Center Experience

Objective

To evaluate the safety and efficacy of balloon pulmonary angioplasty (BPA) in patients with chronic thromboembolic pulmonary hypertension (CTEPH) seen at a US medical center.

Patients and Methods

Patients with inoperable or residual postendarterectomy CTEPH who underwent BPA at Mayo Clinic in Rochester, Minnesota, between August 11, 2014, and May 17, 2018, were included. Invasive hemodynamic, clinical, laboratory, and echocardiographic data were collected and analyzed retrospectively.

Results

We identified 31 patients (26 with inoperable CTEPH and 5 with residual postendarterectomy CTEPH) who underwent 75 BPA procedures performed in a staged manner to reduce complications. The median number of sessions was 2 (interquartile range [IQR], 1-3) per patient, and the number of vessels treated per session was 3 (IQR, 2-3). Of the 31 patients, 24 (77.4%) were taking pulmonary vasodilators and 22 (71.0%) were taking riociguat. The mean pulmonary arterial pressure decreased from 40 mm Hg (IQR, 29-48 mm Hg) to 29 mm Hg (IQR, 25-37 mm Hg; P<.001); pulmonary vascular resistance decreased from 5.5 Wood units (WU) (IQR, 3.0-7.6 WU) to 3.3 WU (2.2-5.2 WU; P<.001). The follow-up 6-minute walk test was performed in 13 patients and improved from 402 m (IQR, 311-439 m) to 439 m (366-510 m; P=.001). Of the 31 patients, 19 (61.3%) had improvement in New York Heart Association functional class. The mean ± SD nadir of minute ventilation/carbon dioxide production decreased by 3.4±5.5 (P=.03), reflecting improved ventilatory efficiency. Complications included hemoptysis requiring overnight intensive care unit observation (n=1) and cardiac tamponade requiring pericardiocentesis (n=1). One patient had reperfusion injury requiring intubation, recovered, and was dismissed to home but died unexpectedly within less than 30 days of the procedure. Serious complications occurred in 3 of the 75 BPA procedures (4.0%).

Conclusion

Our experience with BPA revealed that this procedure has acceptable risk and improves hemodynamics, functional class, and exercise tolerance in patients with inoperable or residual CTEPH.

Long-term clinical value and outcome of riociguat in chronic thromboembolic pulmonary hypertension

Background

To improve clinical outcome, patients with inoperable and residual chronic thromboembolic pulmonary hypertension (CTEPH) can be treated with riociguat. The aim of this study is to explore long-term outcomes and to compare our 'real world' data with previous research.

Methods

We included all consecutive patients with technical inoperable and residual CTEPH, in whom riociguat therapy was initiated from January 2014 onwards, with patients followed till January 2019. Survival, clinical worsening (CW), functional class (FC), N-terminal pro brain natriuretic peptide (NT-proBNP) and 6-minute walking distance (6MWD) were described yearly after riociguat initiation.

Results

Thirty-six patients (50% female, mean age 64.9 ± 12.1 years, 54% WHO FC III/IV and 6MWD 337 ± 138 m could be included, with a mean follow-up of 2.3 ± 1.2 years. Survival and CW-free survival three years after initiation of riociguat were 94% and 78%, respectively. The 6MWD per 10 m at baseline was a significant predictor (HR 0.90 [0.83-0.97], p = 0.009) for CW. At three years follow-up the WHO FC and 6MWD improved and NT-proBNP decreased compared to baseline.

Conclusion

Our study confirms that riociguat is an effective treatment in patients with technical inoperable and residual CTEPH at long-term follow-up. Although our results are consistent with previous studies, more 'real world' research is necessary to confirm long-term results.

High perfusion pressure as a predictor of reperfusion pulmonary injury after balloon pulmonary angioplasty for chronic thromboembolic pulmonary hypertension

BACKGROUND

Clinical efficacy of balloon pulmonary angioplasty (BPA) to the patients with non-operable chronic thromboembolic pulmonary hypertension (CTEPH) for improving pulmonary hemodynamics and exercise tolerance has been reported in these several years. However, reperfusion pulmonary injury (RPI) remains to be a major complication of BPA to overcome. This study elucidated the local predictor of RPI.

METHODS

Twenty-eight consecutive patients with non-operable CTEPH underwent BPA for lesions in the segmental or sub-segmental vessels. Pre- and post-BPA pulmonary arterial pressures at proximal (Pp) and distal (Pd) to the stenosis were measured by a 0.014-in. pressure wire. Positive or negative RPI was evaluated by chest computed tomography in each re-perfused segment separately 4 h after BPA.

RESULTS

Pressure measurements pre- and post-BPA were obtained from 110 lesions, where Pd and pressure ratio (Pd/Pp) increased after BPA in all lesions. Among them, RPI was observed in 49 lesions (44.5%). In the RPI-positive lesions, post-BPA Pd and post-BPA Pd/Pp were higher compared with the RPI-negative lesions. Multivariate logistic analysis revealed that the post-BPA Pd was independently associated with RPI incidence. Receiver operating characteristic curve analysis demonstrated the best cut-off value of 19.5 mm Hg for post-BPA Pd to predict RPI.

CONCLUSIONS

High reperfusion pressure after BPA could be a predictor of RPI. Monitoring local pressure during BPA procedure may have a potential to reduce the incidence of RPI.