Patient-Reported Long-Term Outcome of Balloon Pulmonary Angioplasty for Inoperable CTEPH.

BACKGROUND: Balloon pulmonary angioplasty (BPA) is a promising interventional treatment for inoperable chronic thromboembolic pulmonary hypertension (CTEPH). Evidence in favor of BPA is growing, but long-term data remain scarce. The Cambridge Pulmonary Hypertension Outcome Review (CAMPHOR) is validated for the assessment of patients with pulmonary hypertension within three domains: symptoms, activity, and quality of life (QoL). The aim of the present study was to evaluate the long-term effects of BPA on these domains in patients with inoperable CTEPH. METHODS: Between March 2014 and August 2019, technically inoperable patients with target lesions for BPA were included in this prospective, observational study. CAMPHOR scores were compared between baseline (before the first BPA) and 6 months after the last intervention and also for scores assessed at annual follow-ups. RESULTS: A total of 152 patients had completed a full series of BPA interventions and a 28 (interquartile range [IQR]: 26-32) week follow-up. Further follow-up assessments including the CAMPHOR score were performed 96 (IQR: 70-117) weeks, 178 (IQR: 156-200) weeks, and 250 (IQR: 237-275) weeks after the last intervention. From baseline to the last follow-up, CAMPHOR scores for symptoms, activity, and QoL improved from 9 (IQR: 6-14) to 3 (IQR: 0-9) (p < 0.001), 8 (IQR: 5-12) to 4 (IQR: 2-8) (p < 0.001), and 5 (IQR: 2-9) to 1 (IQR: 0-5) (p < 0.001). CONCLUSION: BPA leads to long-lasting, significant improvement of symptoms, physical capacity, and QoL in inoperable CTEPH patients.

Development of renal function during staged balloon pulmonary angioplasty for inoperable chronic thromboembolic pulmonary hypertension.

Balloon pulmonary angioplasty (BPA), for chronic thromboembolic pulmonary hypertension, improves pulmonary and systemic hemodynamics. The kidney might benefit from this effect. However, staged BPA therapy comes along with repetitive administration of contrast agent. This study examined the overall effect of BPA therapy on renal function. This study included consecutive patients who underwent BPA treatment and completed a 6-month follow-up between March 2014 and March 2017. Biomarker-based evaluation of renal function was performed at baseline, consecutively prior to and after each BPA and at 6-month follow-up. The 51 patients underwent an average of 5 (±2) BPA sessions. In this course, patients received 133 (±48; 21-300) mL of contrast agent per session and 691 (±24; 240-1410) mL during the whole sequence. Acute kidney injury occurred after 6 (2.3%) procedures. The creatinine [80.1 (IQR 67.8-96.8) µmol/L vs. 77.4 (IQR 66.9-91.5) µmol/L, p = .02] and urea level [13.7 (IQR10.7-16.6) mmol/L vs. 12.5 (IQR 10.0-15.5) mmol/L, p = .02] decreased from baseline to the 6-month follow-up. The estimated glomerular filtration rate (eGFR) [79 (IQR 59-94) mL/min/m2 vs. 79.6 (IQR 67.1-95.0) mL/min/m2, p = .11] did not change. The Chronic kidney disease (CKD) stages at baseline were: G1:15; G2:23; G3a:10; G3b:2; G4:1; G5:0. Among patients with a CKD-stage ≥2, analysis revealed an increase of eGFR, decrease of creatinine and urea from baseline to 6-month follow-up. Among those patients, the baseline-CKD-stage improved in 14 (41.2%) patients. BPA therapy improves pulmonary and systemic hemodynamics, with positive effects on renal function. Repetitive administration of contrast agent seems not to be harmful regarding renal function.

Balloon pulmonary angioplasty for inoperable patients with chronic thromboembolic pulmonary hypertension: the initial German experience.

Balloon pulmonary angioplasty (BPA) is an emerging treatment for patients with inoperable chronic thromboembolic pulmonary hypertension (CTEPH).We report on a prospective series of 56 consecutive patients who underwent 266 BPA interventions (median, five per patient) at two German institutions. All patients underwent a comprehensive diagnostic work-up including right heart catheterisation at baseline and 24 weeks after their last intervention.BPA resulted in improvements in WHO functional class, 6 min walk distance (mean change, +33 m), right ventricular function and haemodynamics, including a decline in mean pulmonary artery pressure by 18% and in pulmonary vascular resistance by 26%. Procedure-related adverse events occurred in 9.4% of the interventions. The most common complications were related to pulmonary vascular injury and consecutive pulmonary bleeding. Most of these events were asymptomatic and self-limiting, but one patient died from pulmonary bleeding, resulting in a mortality rate of 1.8%.BPA resulted in haemodynamic and clinical improvements but was also associated with a considerable number of complications, including one fatal pulmonary bleeding. As the effects of BPA on survival are unknown, randomised controlled outcome trials comparing BPA with approved medical therapies in patients with inoperable CTEPH are required to allow for appropriate risk-benefit assessments.

Native T1 mapping and extracellular volume fraction measurement for assessment of right ventricular insertion point and septal fibrosis in chronic thromboembolic pulmonary hypertension.

OBJECTIVES: The aim of this study was to assess septal and right ventricular insertion point (RVIP) fibrosis in patients with chronic thromboembolic pulmonary hypertension (CTEPH) via native T1 mapping and extracellular volume fraction (ECV) determination and to analyze correlations with functional parameters. METHODS: Imaging was performed at 1.5 Tesla in 24 patients diagnosed with CTEPH and 24 controls. T1 values were measured within the septal myocardium, the upper and lower RVIP, and the lateral wall at basal short axis section. RESULTS: The mean septal native T1 values were 1012.8 ms ± 50.5 in the CTEPH group and 956.9 ms ± 24.4 in controls (p < 0.001), upper RIVP 1050.8 ms ± 64.2 vs. 965.3 ms ± 37.1 (p < 0.001), and lower RVIP 1084.4 ms ± 93.1 vs. 959.8 ms ± 40.4 (p < 0.001). The corresponding mean ECV values were also significantly increased in the CTEPH group (p < 0.001). Native septal T1 showed a strong negative correlation with right ventricular ejection fraction (k = -0.92; p = 0.01). CONCLUSIONS: We conclude that native T1 mapping and ECV assessment enable visualization and quantification of septal fibrosis in CTEPH patients. The results also correlate well with right ventricular ejection fraction. Therefore, these parameters might be useful for prognosis and as therapy-monitoring tool in the future. KEY POINTS: • Septal native T1 and ECV values are significantly higher in CTEPH patients. • Native T1 and ECV values are elevated even in absence of LGE. • These techniques therefore enable an improved quantification of septal fibrosis in CTEPH. • Native T1 values also correlate well with right ventricular EF and PA-pressure. • Prognosis and therapy-monitoring might be assessable in the future with these parameters.

Riociguat and balloon pulmonary angioplasty improve prognosis in patients with inoperable chronic thromboembolic pulmonary Hypertension.

BACKGROUND: The combination of riociguat and interventional balloon pulmonary angioplasty (BPA) is currently used to treat patients with inoperable chronic thromboembolic pulmonary hypertension (CTEPH). The aim of the present study was to evaluate the impact of this combination therapy on the prognosis of inoperable CTEPH patients by comparing the long-term survival rates of patients undergoing combination therapy with riociguat and BPA with those of inoperable patients from the first international CTEPH registry who did not receive specific treatment. METHODS: Between March 2014 and August 2019, 138 technically inoperable patients were included in the present prospective, observational cohort study when they were treated with riociguat and BPA at a single CTEPH referral center. Long-term survival of this cohort was compared using propensity score matching with that of inoperable patients recruited between 2007 and 2009 in the first international CTEPH registry. Kaplan-Meier methods were used to evaluate differences in outcomes. RESULTS: Whereas the survival rate in the historical group was 84.6% in the first year, 76.6% in the second, 68.5% in the third, and 58.5% in the fifth year after diagnosis, implementation of riociguat/BPA led to survival rates of 100%, 96.7%, 92.9%, and 90% in the respective follow-up periods. In a comparison of 83 well-matched pairs from the 2 cohorts, survival was markedly better in the group treated with riociguat and BPA than in the historical cohort (HR = 0.145, 95% CI 0.05, 0.421). CONCLUSION: The combination of riociguat and BPA for the treatment of inoperable CTEPH is associated with excellent 5-year survival rates.

Value of Right and Left Ventricular T1 and T2 Blood Pool Mapping in Patients with Chronic Thromboembolic Hypertension before and after Balloon Pulmonary Angioplasty.

BACKGROUND: Parametric imaging has taken a steep rise in recent years and non-cardiac applications are of increasing interest. Therefore, the aim of our study was to assess right (RV) and left ventricular (LV) blood pool T1 and T2 values in patients with chronic thromboembolic pulmonary hypertension (CTEPH) compared to control subjects and their correlation to pulmonary hemodynamic. METHODS: 26 patients with CTEPH (mean age 64.8 years ± 12.8 SD; 15 female), who underwent CMR and right heart catheterization (RHC) before and 6-months after balloon pulmonary angioplasty (BPA), were retrospectively included. Ventricular blood pool values were measured, compared to control subjects (mean age 40.5 years ± 12.8 SD; 16 female) and correlated to invasive measures (CI, mPAP, PVR). RESULTS: In both, control subjects and CTEPH patients, RVT1 and RVT2 were significantly reduced compared to LVT1 and LVT2. Compared to control subjects, RVT2 was significantly reduced in CTEPH patients (p = 0.0065) and increased significantly after BPA (p = 0.0048). Moreover, RVT2 was positively correlated with CI and negatively correlated with mPAP and PVR before (r = 0.5155, r = -0.2541, r = -0.4571) and after BPA (r = 0.4769, r = -0.2585, r = -0.4396). CONCLUSION: Ventricular blood pool T2 mapping might be novel non-invasive CMR imaging marker for assessment of disease severity, prognosis, follow-up and even therapy monitoring in PH.

Effects of BPA on right ventricular mechanical dysfunction in patients with inoperable CTEPH - A cardiac magnetic resonance study.

PURPOSE: The aim of this study was to assess effects of balloon pulmonary angioplasty (BPA) on right ventricular (RV) mechanical dysfunction in patients with inoperable chronic thromboembolic pulmonary hypertension (CTEPH) via MRI. METHOD: MRI at 1.5 Tesla and right heart catheterization were performed before and 6 months after BPA in 30 CTEPH patients (mean age 63.4 ± 10.6 years; 17 female). Feature-tracking strain analysis, including global longitudinal (GLS), circumferential (GCS), and radial (GRS) strain, was performed and compared with right ventricular function, myocardial remodelling (assessed by native T1 times), and pulmonary haemodynamics (mean pulmonary arterial pressure and pulmonary vascular resistance). RESULTS: RVEF (35.9% to 48.4%) increased and mPAP (42.1 mmHg to 33.1 mmHg) and PVR (551.8 to 377.7 dyn∙s/cm5) decreased after BPA (all p < 0.0001). Moreover, RV strain increased (GLS -19.9 to -24.0%, p = 0.0003; GCS -9.4 to -11.0%, p = 0.0022; GRS 38.2 to 50.7%, p = 0.001) and septal native area-adjusted T1 time (AA-T1) decreased (1019.4 to 988.7 ms, p < 0.0001). GLS revealed the best correlations with RVEF (before BPA r = -0.75; after BPA r = -0.54), mPAP (r = 0.36; r = 0.52), PVR (r = 0.49; r = 0.48), and AA-T1 (r = 0.44; 0.19). CONCLUSION: RV mechanical dysfunction, pulmonary haemodynamics, and myocardial remodelling are markedly improved by BPA. Moreover, RV strain values showed good correlations with RV function, pulmonary haemodynamics, and myocardial remodelling. Therefore, strain analysis might provide new insights regarding therapy outcome, monitoring, and prognosis.

Complications of balloon pulmonary angioplasty for inoperable chronic thromboembolic pulmonary hypertension: Impact on the outcome.

BACKGROUND: Balloon pulmonary angioplasty (BPA) is an emerging interventional treatment for inoperable chronic thromboembolic pulmonary hypertension (CTEPH) that targets subsegmental branches of the pulmonary artery. As the reported complication rates are high, the aim of the present study was to evaluate the effects of certain complications on the outcome after treatment. METHODS: From March 2014 to December 2019, a total of 235 patients with inoperable CTEPH underwent BPA. Of these patients, 140 were included who completed a follow-up examination 6 months after the last intervention; another 2 patients deceased due to complications of BPA. RESULTS: A high baseline pulmonary vascular resistance (PVR) >6.6 WU correlated with a higher rate of complications (mostly pulmonary artery perforations). Wire perforation during BPA did not correlate with worse outcome in terms of PVR reduction. The complication rate per intervention decreased from 21% to 14% during the 5 year period of the study. CONCLUSIONS: Complications are frequently observed in BPA, but the mortality rate is very low in expert centers. Importantly, the occurrence of complications does not portend a worse outcome.

Balloon pulmonary angioplasty in the treatment of chronic thromboembolic pulmonary hypertension: recent advances and future perspectives.

Chronic thromboembolic pulmonary hypertension constitutes a significant late sequela of pulmonary embolism. It is defined by precapillary pulmonary hypertension with mismatched perfusion defects and pulmonary arterial lesions after at least 3 months of effective anticoagulation. Symptomatic patients who do not have pulmonary hypertension yet fulfill all other criteria are diagnosed with chronic thromboembolic disease. The treatment of chronic thromboembolic pulmonary hypertension is based on 3 pillars: pulmonary endarterectomy, pulmonary arterial hypertension-targeted medication, and balloon pulmonary angioplasty. Surgical pulmonary endarterectomy is the standard of care and can be performed in 2/3 of all patients. Targeted medication with or without balloon pulmonary angioplasty is reserved for inoperable patients or those with residual pulmonary hypertension after surgical treatment. Despite the lack of profound evidence, the treatment of chronic thromboembolic disease is similar to that of patients with pulmonary hypertension: pulmonary endarterectomy is offered to operable individuals, whereas balloon pulmonary angioplasty is considered in inoperable patients. Since therapeutic strategies are complex, and diagnostic and therapeutic procedures-demanding, treatment in a specialized, experienced center is mandatory.

Noninvasive prediction of pulmonary hemodynamics in chronic thromboembolic pulmonary hypertension by electrocardiogram-gated computed tomography.

PURPOSE: The aim of the study was to investigate the potential of electrocardiogram (ECG)-gated computed tomography pulmonary angiography (CTPA) as a predictor of disease severity in patients with chronic thromboembolic pulmonary hypertension (CTEPH). METHOD: Forty-five CTEPH patients with a mean age of 63.8 years±12.7 y (±standard deviation) who had undergone ECG-gated CTPA and right heart catheterization (RHC) were included in the study. Right ventricular to left ventricular volume ratio (RVV/LVV), diameter ratio on 4-chamber view (RVD4CH/LVD4CH), pulmonary trunk (PT) diameter, PT to aortic diameter ratio (PT/A), and septal angle were correlated to mean pulmonary artery pressure (mPAP). Moreover, RVV/LVV and RVD4CH/LVD4CH were adjusted to pulmonary diameter index (PADi) and PT/A index. Areas under the curve (AUC) for predicting mPAP above 40 mmHg, 35 mmHg, and 30 mmHg were calculated. RESULTS: RVD4CH/LVD4CH revealed the strongest correlation to mPAP before (r = 0.6507) and after (r = 0.7650; p < 0.0001) PT/A adjustment. The AUCs for predicting pH with mPAP over 40 mmHg and 30 mmHg were 0.9229 and 0.864, respectively. A cutoff value of 1.298 enabled prediction of pH with mPAP over 40 mmHg with a sensitivity, specificity, positive predictive, and negative predictive value of 80.00 %, 95.83 %, 88.46 %, and 94.12 %, respectively. Intra- and interobserver variability were excellent for all parameters. CONCLUSION: Combining different and easily evaluable ECG-gated CTPA parameters enables excellent prediction of pulmonary hemodynamics in CTEPH patients. Ventricular diameter ratio on 4-chamber view adjusted by the PT/A ratio yielded the best correlation to mPAP.

Clinical and Functional Characteristics of Patients with Unclassifiable Interstitial Lung Disease (uILD): Long-Term Follow-Up Data from European IPF Registry (eurIPFreg).

(1) Aim of the study: In spite of extensive research, up to 20% of interstitial lung diseases (ILD) patients cannot be safely classified. We analyzed clinical features, progression factors, and outcomes of unclassifiable ILD (uILD). (2) Methods: A total of 140 uILD subjects from the University of Giessen and Marburg Lung Center (UGMLC) were recruited between 11/2009 and 01/2019 into the European Registry for idiopathic pulmonary fibrosis (eurIPFreg) and followed until 01/2020. The diagnosis of uILD was applied only when a conclusive diagnosis could not be reached with certainty. (3) Results: In 46.4% of the patients, the uILD diagnosis was due to conflicting clinical, radiological, and pathological data. By applying the diagnostic criteria of usual interstitial pneumonia (UIP) based on computed tomography (CT), published by the Fleischner Society, 22.2% of the patients displayed a typical UIP pattern. We also showed that forced vital capacity (FVC) at baseline (p = 0.008), annual FVC decline ≥10% (p < 0.0001), smoking (p = 0.033), and a diffusing capacity of the lung for carbon monoxide (DLco) ≤55% of predicted value at baseline (p < 0.0001) were significantly associated with progressive disease. (4) Conclusions: The most important prognostic factors in uILD are baseline level and decline in lung function and smoking. The use of Fleischner diagnostic criteria allows further differentiation and accurate diagnosis.

Lung CT Densitometry in Idiopathic Pulmonary Fibrosis for the Prediction of Natural Course, Severity, and Mortality.

BACKGROUND: In this study, we retrospectively assessed the relationships among physiologic measurements, survival, and quantitative high-resolution CT (HRCT) scanning indexes in patients with idiopathic pulmonary fibrosis (IPF). METHODS: Seventy patients (48 male; mean [SD] age, 66.4 [9.0] years) with IPF were enrolled in the study. After segmentation of the lungs in thin-section CT scanning with the patient in the supine position at full inspiration, we assessed following parameters: mean lung attenuation (MLA), skewness, kurtosis, peak attenuation, total lung area, inflexion point with slope, and area right of the inflexion point (AROIP). Additionally, FVC, FEV1, total lung capacity, diffusing capacity or transfer factor of the lung for carbon monoxide (Dlco), and 6-min walk distance were analyzed. Univariate and multivariate analysis were used for the prediction of physiologic outcomes by HRCT scanning indexes and then were correlated to survival in a proportional hazards analysis. RESULTS: The strongest correlation was observed between MLA and FEV1, with an r of -0.63. MLA, peak attenuation, slope, attenuation, and AROIP correlated negatively with all physiologic measurements. AROIP was the best predictor of Dlco. Analysis for prediction of mortality showed that AROIP, kurtosis, and FVC were related significantly to survival. Multivariate regression revealed a significant impact of only AROIP (among age, sex, MLA, skewness, kurtosis, FVC, and Dlco) on survival. CONCLUSIONS: These data indicate that HRCT scanning indexes are correlated to physiologic measurements. The newly defined parameter, AROIP, is of additive value for prediction of outcome. TRIAL REGISTRY: ClinicalTrials.gov; No.: NCT02951416; URL: www.clinicaltrials.gov.

Sequential treatment with riociguat and balloon pulmonary angioplasty for patients with inoperable chronic thromboembolic pulmonary hypertension.

Riociguat is the treatment of choice for inoperable patients with chronic thromboembolic pulmonary hypertension (CTEPH). We addressed here whether additional balloon pulmonary angioplasty (BPA) provides further benefits. A prospective series of 36 consecutive patients with inoperable CTEPH were treated with riociguat at least three months before BPA. All patients underwent diagnostic workup at baseline, before BPA treatments, and six months after final intervention. The main outcome measures were pulmonary hemodynamic parameters and World Health Organization (WHO) functional class (FC). Significant improvements in pulmonary hemodynamics and physical capacity were observed for riociguat treatment, and subsequent BPA interventions yielded further benefits. With targeted medication, WHO FC improved by at least one class in 13 (36.1%) patients ( P = 0.01). Hemodynamic assessment showed significant improvements in mean pulmonary arterial pressure (mPAP) (49 ± 12 mmHg vs. 43 ± 12 mmHg; P = 0.003) and PVR (956 ± 501 dyn·s·cm-5 vs. 517 ± 279 dyn·s·cm-5; P = 0.0001). Treatment with a combination of targeted medication and BPA resulted in WHO FC improvement in 34 (94.4%) patients. Hemodynamic assessment showed significant improvement in mPAP (43 ± 12 mmHg vs. 34 ± 14 mmHg; P = 0.0001) and PVR (517 ± 279 dyn·s·cm-5 vs. 360 ± 175 dyn·s·cm-5; P = 0.0001). These findings provide, for the first time, support for the therapeutic strategy recommended by current guidelines.

Dynamics of high-sensitivity cardiac troponin T during therapy with balloon pulmonary angioplasty for chronic thromboembolic pulmonary hypertension.

AIMS: Balloon pulmonary angioplasty (BPA) is an interventional treatment modality for inoperable chronic thromboembolic pulmonary hypertension (CTEPH). Therapy monitoring, based on non-invasive biomarkers, is a clinical challenge. This post-hoc study aimed to assess dynamics of high-sensitivity cardiac troponin T (hs-cTnT) as a marker for myocardial damage and its relation to N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels as a marker for cardiac wall stress. METHODS AND RESULTS: This study included 51 consecutive patients who underwent BPA treatment and completed a 6-month follow-up (6-MFU) between 3/2014 and 3/2017. Biomarker measurement was performed consecutively prior to each BPA and at 6-MFU. In total, the 51 patients underwent an average of 5 BPA procedures. The 6-month survival rate was 96.1%. The baseline (BL) meanPAP (39.5±12.1mmHg) and PVR (515.8±219.2dyn×sec×cm-5) decreased significantly within the 6-MFU (meanPAP: 32.6±12.6mmHg, P<0.001; PVR: 396.9±182.6dyn×sec×cm-5, P<0.001). At BL, the median hs-cTnT level was 11 (IQR 6-16) ng/L and the median NT-proBNP level was 820 (IQR 153-1872) ng/L. The levels of both biomarkers decreased steadily after every BPA, showing the first significant difference after the first procedure. Within the 6-MFU, hs-cTnT levels (7 [IQR 5-12] ng/L; P<0.001) and NT-proBNP levels (159 [IQR 84-464] ng/l; P<0.001) continued to decrease. The hs-cTnT levels correlated with the PVR (rrs = 0.42; p = 0.005), the meanPAP (rrs = 0.32; p = 0.029) and the NT-proBNP (rrs = 0.51; p<0.001) levels at BL. CONCLUSION: Non-invasive biomarker measurement provides valuable evidence for the decreasing impairment of myocardial function and structure during BPA therapy. Changes in hs-cTNT levels are suggestive for a reduction in ongoing myocardial damage.

Balloon pulmonary angioplasty for inoperable patients with chronic thromboembolic disease.

Symptomatic patients with residual pulmonary perfusion defects or vascular lesions but no pulmonary hypertension at rest are diagnosed with chronic thromboembolic disease (CTED). Balloon pulmonary angioplasty (BPA) is an emerging treatment for patients with inoperable chronic thromboembolic pulmonary hypertension (CTEPH), but data regarding the safety and efficacy of BPA in patients with CTED are lacking. We report a prospective series of ten consecutive patients with CTED who underwent 35 BPA interventions (median of four per patient) at two German institutions. All patients underwent a comprehensive diagnostic workup at baseline and 24 weeks after their last intervention. BPA was safe, with one pulmonary vascular injury and subsequent self-limiting pulmonary bleeding as the only complication (2.9% of the interventions, 10% of the patients). After the procedures, World Health Organization functional class, 6-min walking distance, pulmonary vascular resistance, and pulmonary arterial compliance improved, and NT-proBNP concentrations declined in 9/10 patients. BPA may be a new treatment option for carefully selected patients with CTED. A larger, prospective, international registry is required to confirm these results.

N-terminal pro-B-type natriuretic peptide for monitoring after balloon pulmonary angioplasty for chronic thromboembolic pulmonary hypertension.

BACKGROUND: Balloon pulmonary angioplasty (BPA) is an emerging interventional treatment option for chronic thromboembolic pulmonary hypertension (CTEPH). The non-invasive monitoring of CTEPH patients is a clinical challenge. In this study we examined changes in N-terminal pro-B-type natriuretic peptide (NT-proBNP) in patients undergoing BPA for inoperable CTEPH and related them to peri-procedural success. METHODS: In this study we analyzed a total of 51 consecutive patients who underwent BPA treatment and completed a 6-month follow-up (6-MFU) between March 2014 and March 2017. Serum samples for NT-proBNP measurement were collected before every BPA and at 6-MFU. RESULTS: The 51 patients underwent 265 interventions involving angioplasty of a total of 410 vessels. The 6-month survival rate was 96.1%. The baseline (BL) mean pulmonary artery pressure (PAP) was 39.5 ± 12.1 mm Hg, pulmonary vascular resistance (PVR) was 515.8 ± 219.2 dynes/s/cm5 and the median NT-proBNP level was 820 (153 to 1,871.5) ng/liter. At BL, World Health Organization functional class (FC) was ≥III in 96.1% of the patients, whereas, at 6-MFU, 11.8% were in WHO FC ≥III. At 6-MFU, mean PAP (32.6 ± 12.6 mm Hg; p < 0.001), PVR (396.9 ± 182.6 dynes/s/cm5; p < 0.001) and NT-proBNP (159.3 [84.4 to 464.3] ng/liter; p < 0.001) levels were reduced. The decrease in NT-proBNP levels correlated with the decrease in mean PAP (rrs = 0.43, p = 0.002) and PVR (rrs = 0.50, p = 0.001). A reduction in the NT-proBNP level of 46% indicated a decrease in mean PAP of ≥25% (area under the curve [AUC] = 0.71) and a reduction of 61% indicated a decrease in PVR of ≥35% (AUC 0.77). CONCLUSIONS: Our results demonstrate that NT-proBNP levels decrease after BPA, providing valuable evidence of procedural success. NT-proBNP measurement allows identification of patients who are BPA non-responders and may thus be a valuable adjunct in therapy monitoring.

Combined pulmonary endarterectomy and balloon pulmonary angioplasty in patients with chronic thromboembolic pulmonary hypertension.

BACKGROUND: Pulmonary endarterectomy (PEA) is a curative treatment option for more than 60% of patients with chronic thromboembolic pulmonary hypertension (CTEPH). For selected inoperable patients, interventional balloon pulmonary angioplasty (BPA) has recently been established in addition to medical treatment. This approach disrupts scar tissue occluding the pulmonary arteries, leading to an improvement in parenchymal perfusion. CTEPH is occasionally heterogeneous, with operable disease on one side but peripheral, inoperable changes on the contralateral side. Performing unilateral PEA (on the operable side only) in these patients may lead to a worse hemodynamic outcome and increased mortality compared with patients who that can be surgically corrected bilaterally. We sought to determine the feasibility, safety, and benefits of BPA applied to the contralateral lung in several patients with predominantly unilateral disease that was amenable to treatment by PEA. METHODS: Standard unilateral PEA in deep hypothermic circulatory arrest was performed in 3 CTEPH patients with poor pulmonary hemodynamics, and inoperability of the contralateral pulmonary artery obstructions was confirmed. The inoperable side was treated by BPA. The intervention was performed during the rewarming phase of cardiopulmonary bypass. RESULTS: A dramatic improvement in pulmonary hemodynamics, with a mean reduction in pulmonary vascular resistance of 842 dyne · sec/cm(5), was achieved in all patients. World Health Organization Functional Class was also significantly improved at the midterm follow-up. CONCLUSIONS: The combination of surgical PEA and interventional BPA is a new treatment option for highly selected high-risk CTEPH patients. A multidisciplinary CTEPH expert team is a basic pre-requisite for this complex concept.

Three-dimensional imaging and morphometric analysis of alveolar tissue from microfocal X-ray-computed tomography.

We evaluated microfocal X-ray-computed tomography (micro-CT) as a method to visualize lung architecture two and three dimensionally and to obtain morphometric data. Inflated porcine lungs were fixed by formaldehyde ventilation. Tissue samples (8-mm diameter, 10-mm height) were stained with osmium tetroxide, and 400 projection images (1,024 x 1,024 pixel) were obtained. Continuous isometric micro-CT scans (voxel size 9 microm) were acquired to reconstruct two- and three-dimensional images. Tissue samples were sectioned (8-microm thickness) for histological analysis. Alveolar surface density and mean linear intercept were assessed by stereology-based morphometry in micro-CT scans and corresponding histological sections. Furthermore, stereology-based morphometry was compared with morphometric semi-automated micro-CT analysis within the same micro-CT scan. Agreement of methods was assessed by regression and Bland-Altman analysis. Comparing histology with micro-CT, alveolar surface densities (35.4 +/- 2.4 vs. 33.4 +/- 1.9/mm, P < 0.05) showed a correlation (r = 0.72; P = 0.018) with an agreement of 2 +/- 1.6/mm; the mean linear intercept (135.7 +/- 14.5 vs. 135.8 +/- 15 microm) correlated well (r = 0.97; P < 0.0001) with an agreement of -0.1 +/- 3.4 microm. Semi-automated micro-CT analysis resulted in smaller alveolar surface densities (33.4 +/- 1.9 vs. 30.5 +/- 1/mm; P < 0.01) with a correlation (r = 0.70; P = 0.023) and agreement of 2.9 +/- 1.4/mm. Non-destructive micro-CT scanning offers the advantage to visualize the spatial tissue architecture of small lung samples two and three dimensionally.

Micro-CT of the human lung: imaging of alveoli and virtual endoscopy of an alveolar duct in a normal lung and in a lung with centrilobular emphysema--initial observations.

The appearance of human lung parenchyma at the structural level of alveoli was investigated by the use of micro-computed tomography (CT). Approval for use of autopsy lungs was given by the head of the pathology institute of the university, in accordance with the requirements of the State Ministry of Science and Arts and without the need for institutional review board approval. Two human lungs (one normal lung and one lung with centrilobular emphysema of a mild to moderate degree) were inflated and fixed with hot formalin vapor. Lung specimens excised from the superior segment of the left lower lobe (B6) were stained with silver nitrate in a vacuum and investigated at a volume of interest of 4 mm for each side with a voxel size of 14 mum. Normal-size and enlarged alveoli became visible. A three-dimensional reconstruction of the terminal airspaces made virtual endoscopy of the alveolar ducts possible.

Puncture of the popliteal artery using a Doppler-equipped (SMART) needle in transpopliteal interventions.

The puncture of the popliteal artery for percutaneous intervention is usually performed under fluoroscopic guidance or with the assistance of percutaneous ultrasound to avoid accidental arteriovenous fistulas. We present our experience in 119 cases with the use of a Doppler ultrasound equipped Seldinger needle (SMART needle) for the detection and puncture of the popliteal artery. In 119 interventions in 103 patients, the puncture of the popliteal artery was performed with the SMART needle. The puncture was successful in 94.1% (112 of 119) of cases. Six (5.2%) complications occurred during puncture: four hematomas (no therapy required) and two arteriovenous fistulas (treated by manual compression solely). The subsequent 112 interventions in 103 patients [98 percutaneous transluminal angioplasty (PTA), 8 PTA with stent implantations, 4 PTA with thrombolysis, 2 thrombolyses] were technically successful in 79.5% (89 of 112). The SMART-needle-guided popliteal puncture showed to be safe, fast, and easy to perform, which allowed the use of this technique by radiologists in training. The rates of success and complications are comparable to reported results for other visualization techniques, whereas time, effort, and training required are lower. This may contribute to a more widespread use of the transpopliteal access for interventions and therefore offers a therapeutic option in addition to vascular surgery.