Exercise MR-proANP unmasks latent right heart failure in CTEPH

Background

Chronic right heart failure is the major determinant of outcome in chronic thromboembolic pulmonary hypertension (CTEPH). Thus, its early detection is crucial for optimal patient management. Hemodynamic assessment with invasive right heart catheterization and the measurement of natriuretic peptides at rest are established diagnostic tools in this context. An elevated right atrial pressure (RAP) is a sensitive parameter of right right heart failure. Mid-regional pro-atrial natriuretic peptide (MR-proANP) is a natriuretic peptide that reflects right atrial stress levels.

There is a growing recognition of exercise diagnostics in the assessment of right heart failure, particularly in patients with normal or borderline findings at rest. There are no data on the dynamics of MR-proANP in correlation to RAP during physical exercise.

Purpose

The present study was designed to investigate the dynamics of RAP and MR-proANP during physical exercise in patients with CTEPH and to determine whether these parameters might serve as a tool to measure exercise-dependent atrial stress as an indicator of right heart failure.

Methods

This observational cohort study included 100 CTEPH patients who underwent right heart catheterization during physical exercise (eRHC). Blood samples for MR-proANP measurement were taken prior, during, and after eRHC. MR-proANP levels were correlated to RAP levels at rest, at peak exercise (eRAP), and during recovery. RAP at rest ≤7 mmHg was defined as normal and eRAP >15 mmHg as suggestive of right heart failure.

Results

During eRHC mean RAP increased from 6±4 mmHg to 16±7 mmHg (p<0.001). MR-proANP levels and dynamics correlated with RAP at rest (rs=0.61; p<0.001; figure 1a) and at peak exercise (rs=0.66; p<0.001; Figure 1b). Furthermore, the relative percent increase in MR-proANP correlated with the relative percent increase in eRAP (rs=0.52; p<0.001; Figure 1c) Logistic regression analysis revealed the peak MR-proANP level (B=0.058; p=0.004) and the right atrial area (B=0.389; p<0.001) to be associated with eRAP dynamics. A peak MR-proANP level ≥139 pmol/L (AUC=0.81) and recovery level ≥159 pmol/L (AUC=0.82) predicted an eRAP >15 mmHg. Physical exercise unmasked RH failure in 39% of patients with normal RAP at rest; they were also characterized by a more distinct increase in MR-proANP levels (p=0.005) and higher peak (p<0.001) and recovery levels (p<0.001).

Conclusions

RAP and MR-proANP dynamics unmask manifest and latent right heart failure in CTEPH patients, which may be useful in estimating prognosis.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): SFB 1213 area CP-01 projectWilliam G. Kerckhoff-FoundationKerckhoff Heart Research Institute (KHFI)German Center for Cardiovascular Research (DZHK)

Body fluid status in patients with pulmonary arterial hypertension and chronic thromboembolic pulmonary hypertension

Introduction

Body fluid status can be determined by plasma volume status and extracellular water to total body water (ECW/TBW) ratio and is a well-known parameter associated with survival in patients with chronic heart failure (1–3). However, its prognostic impact in patients with pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTEPH) is not fully understood.

Methods

409 patients with PAH and CTEPH who entered the Giessen PH registry were included in this study (4). Plasma volume status was estimated using Duarte formula (ePVS = (1 − hematocrit) / hemoglobin × 100). ECW was calculated via Peters formula ((−2.47 × 0.842 + 8.76 × body surface area) for men and (−1.96 × 0.572 + 8.05 × body surface area) for women) and TBW via Watson formula ((2.447 − [0.09516 × age] + [0.1073 × height] + [0.3362 × body weight]) for men and (−2.097 + [0.1069 × height] + [0.2466 × body weight]) for women). Statistical analyzes were performed with R (The R Foundation).

Results

Median age of the included patients was 65 [53, 74] years. Median ePVS and ECW/TBW ratio were 4.5 [3.9, 5.5] and 0.39 [0.37, 0.40]. Correlation analyses revealed that ePVS correlates with pulmonary artery wedge pressure (PAWP), pulmonary vascular resistance (PVR), cardiac index, and mixed venous oxygen saturation (SvO2), whereas ECW/TBW ratio did not correlate with pulmonary hemodynamics. Accordingly, univariate Cox regression revealed that ePVS but not ECW/TBW ratio was associated with mortality (HR: 1.18 [1.02, 1.37]). ePVS remained as an independent prognostic parameter in multivariate Cox regression analysis. Patients with high ePVS showed significantly decreased survival rates (log-rank p<0.001).

Conclusion

ePVS but not ECW/TBW ratio is associated with prognostic parameters such as PVR, cardiac index and SvO2. Thus, ePVS may be an independent prognostic parameter in patients with PAH and CTEPH.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): Deutsche Forschungsgemeinschaft (DFG, German Research Foundation)

Physical Activity and Mental Health of Patients with Pulmonary Hypertension during the COVID-19 Pandemic

The aim of the study was to analyze the effect of personal restrictions on physical activity, mental health, stress experience, resilience, and sleep quality in patients with pulmonary hypertension (PH) during the “lockdown” period of the COVID-19 pandemic. In total, 112 PH patients and 52 age-matched healthy control subjects completed a questionnaire on the topics of physical activity, mental health, resilience, and sleep quality. PH patients had significantly lower physical activity, mental health, and sleep quality compared to age-matched healthy controls. Physical activity positively correlated with mental health and sleep quality in the PH group. Mental wellbeing and life satisfaction could be predicted by total physical activity, sleep, stress level, and resilience. PH patients appeared as an especially vulnerable group, demanding interventions to promote an active lifestyle and protect mental health in these patients. This could be helpful in counseling on how to carry out physical activity while maintaining infection control.

Detection of infrared fluorescence of carbon dioxide in R Leonis with SOFIA/EXES

We report on the detection of hot CO2 in the O-rich AGB star R Leo based on high spectral resolution observations in the range 12.8 - 14.3 μm carried out with the Echelon-cross-Echelle Spectrograph (EXES) mounted on the Stratospheric Observatory for Infrared Astronomy (SOFIA). We have found ≃ 240 CO2 emission lines in several vibrational bands. These detections were possible thanks to a favorable Doppler shift that allowed us to avoid contamination by telluric CO2 features. The highest excitation lines involve levels at an energy of ≃ 7000 K. The detected lines are narrow (average deconvolved width ≃ 2.5 km s-1) and weak (usually ≲ 10% the continuum). A ro-vibrational diagram shows that there are three different populations, warm, hot, and very hot, with rotational temperatures of ≃ 550, 1150, and 1600 K, respectively. From this diagram, we derive a lower limit for the column density of ≃ 2.2 × 1016 cm-2. Further calculations based on a model of the R Leo envelope suggest that the total column density can be as large as 7 × 1017 cm -2 and the abundance with respect to H2 - 2.5 × 10-5. The detected lines are probably formed due to de-excitation of CO2 molecules from high energy vibrational states, which are essentially populated by the strong R Leo continuum at 2.7 and 4.2 μm.

Anti-interleukin-5 therapy (mepolizumab) in life-threatening asthma attack: A case-based discussion

We report about a case of a compassionate off-label use of the anti-interleukin-5-agent mepolizumab in a ventilated patient with life-threatening asthma attack in eosinophilic asthma. The patient suffered from severe eosinophilic asthma and was transmitted to our hospital with an asthma attack and a life-threatening respiratory state under ventilation. Since high dose steroids had not yielded a sufficient respiratory improvement mepolizumab was administered subcutaneously. After administration of mepolizumab respiratory state and ventilation parameter improved significantly. Two days after administration the patient was weaned could be extubated 8 days later and recovered completely from the asthma attack. The presented clinical case is suggestive of future clinical trials or registry studies to evaluate potential clinical benefits of anti-interleukin-5 treatment in patients with severe exacerbations of eosinophilic asthma.

Increased frequency of the restless legs syndrome in adults with cystic fibrosis

BACKGROUND

Patients with cystic fibrosis (CF) may suffer from iron deficiency which is a known risk factor for the restless legs syndrome (RLS), however, its prevalence has not yet been investigated in these subjects.

PATIENTS AND METHODS

Adult out-patients with CF (n = 39) and healthy volunteers (n = 32) were recruited for this study. A diagnosis of RLS was made based on the diagnostic criteria established by the International Restless Legs Syndrome Study Group (IRLSSG). The IRLSSG rating scale was used to assess the severity of the disease. Furthermore, in the CF group, parameters of iron metabolism were measured in peripheral venous blood samples.

RESULTS

The RLS occurred more frequently in the CF patients than the controls (n = 13/33,3% vs. n = 2/6,3%; p < 0,05). In the CF patients suffering from RLS, the mean score of the IRLSSG rating scale was 17,2 ± 9,4 indicating moderate disease severity. Iron deficiency was present in the majority of the CF patients investigated (n = 33/84,6%), however, serum iron, ferritin and transferrin levels as well as transferrin saturation were similar in those with vs. without RLS.

CONCLUSIONS

The frequency of the RLS is increased in adult patients with CF. On an average, its severity is moderate and it is not related to iron deficiency as evaluated by serum parameters of iron metabolism.

Treatment with low-dose tacrolimus inhibits bleeding complications in a patient with hereditary hemorrhagic telangiectasia and pulmonary arterial hypertension

Pulmonary arterial hypertension (PAH) can be found in patients suffering from a loss-of-function mutation of the gene encoding for the activin receptor-like kinase 1 (ALK-1), a bone morphogenetic protein (BMP) type 1 receptor. Interestingly, ALK-1 mutations also lead to hereditary hemorrhagic telangiectasia (HHT), an autosomal dominant disease characterized by arteriovenous malformations (AVMs) leading to potentially life-threatening bleeding complications such as epistaxis. Current therapeutic options for both diseases are limited and often only temporary or accompanied by severe side effects. Here, we report of a patient with a mutation of the ALK-1 gene suffering from both HHT and PAH. Recently, it was shown that tacrolimus increased ALK-1 signaling and had beneficial effects in selected end-stage PAH patients. We thus hypothesized that treatment with tacrolimus may prevent disease progression in this patient. Surprisingly, treatment with low-dose tacrolimus dramatically improved his HHT-associated epistaxis but did not attenuate progression of PAH.

Intravenous treprostinil via an implantable pump in pediatric pulmonary arterial hypertension

Intravenous prostacyclin-based therapy improves survival in children with pulmonary arterial hypertension (PAH), but is typically administered via an external infusion pump, which places a considerable burden on the patient. Implanted pumps may overcome some of the limitations of external pumps. We describe the first long-term use of an implanted pump for intravenous treprostinil delivery in a pediatric patient with PAH. Our patient was experiencing marked dyspnea on exertion despite triple combination therapy with bosentan, sildenafil, and inhaled iloprost. Parenteral prostacyclin-based therapy was discussed and the patient rejected options involving external pumps; she finally chose intravenous treprostinil delivery via an implanted pump (LENUS Pro®; fixed flow rate; 20 ml reservoir). The patient underwent pump implantation in July 2012 (aged 14 years) under general anesthesia with no peri- or postoperative complications. She showed marked improvements in fatigue and dyspnea over the subsequent weeks, and her inhaled iloprost regimen was slowly decreased and stopped after six months. During follow-up, the pump showed an unexpected, progressive increase in flow rate that allowed a treprostinil dose of 170 ng/kg/min to be achieved, but at the cost of shortened intervals between refills. The pump was therefore replaced in August 2017 with a newer model with an adjustable flow rate (Siromedes®). A catheter dislocation was corrected under local anesthesia one week after the replacement surgery. The patient is currently receiving treprostinil 170 ng/kg/min with percutaneous refills every 12–13 days. Thus, implantable pumps might be a valuable alternative to external pumps for treprostinil infusion in pediatric PAH.

Immune-regulating effects of exercise on cigarette smoke-induced inflammation

Long-term cigarette smoking (LTCS) represents an important risk factor for cardiac infarction and stroke and the central risk factor for the development of a bronchial carcinoma, smoking-associated interstitial lung fibrosis, and chronic obstructive pulmonary disease. The pathophysiologic development of these diseases is suggested to be promoted by chronic and progressive inflammation. Cigarette smoking induces repetitive inflammatory insults followed by a chronic and progressive activation of the immune system. In the pulmonary system of cigarette smokers, oxidative stress, cellular damage, and a chronic activation of pattern recognition receptors are described which are followed by the translocation of the NF-kB, the release of pro-inflammatory cytokines, chemokines, matrix metalloproteases, and damage-associated molecular patterns. In parallel, smoke pollutants cross directly through the alveolus-capillary interface and spread through the systemic bloodstream targeting different organs. Consequently, LTCS induces a systemic low-grade inflammation and increased oxidative stress in the vascular system. In blood, these processes promote an increased coagulation and endothelial dysfunction. In muscle tissue, inflammatory processes activate catabolic signaling pathways followed by muscle wasting and sarcopenia. In brain, several characteristics of neuroinflammation were described. Regular exercise training has been shown to be an effective nonpharmacological treatment strategy in smoke-induced pulmonary diseases. It is well established that exercise training exerts immune-regulating effects by activating anti-inflammatory signaling pathways. In this regard, the release of myokines from contracting skeletal muscle, the elevations of cortisol and adrenalin, the reduced expression of Toll-like receptors, and the increased mobilization of immune-regulating leukocyte subtypes might be of vital importance. Exercise training also increases the local and systemic antioxidative capacity and several compensatory mechanisms in tissues such as an increased anabolic signaling in muscle or an increased compliance of the vascular system. Accordingly, regular exercise training seems to protect long-term smokers against some important negative local and systemic consequences of smoking. Data suggest that it seems to be important to start exercise training as early as possible.

Carbon Chemistry in IRC+10216: Infrared Detection of Diacetylene

We present the detection of C4H2 for first time in the envelope of the C-rich AGB star IRC+10216 based on high spectral resolution mid-IR observations carried out with the Texas Echelon-cross-Echelle Spectrograph (TEXES) mounted on the Infrared Telescope Facility (IRTF). The obtained spectrum contains 24 narrow absorption features above the detection limit identified as lines of the ro-vibrational C4H2 band ν 6 + ν 8 ( σ u + ) . The analysis of these lines through a ro-vibrational diagram indicates that the column density of C4H2 is (2.4 ± 1.5) × 1016 cm-2. Diacetylene is distributed in two excitation populations accounting for 20 and 80% of the total column density and with rotational temperatures of 47 ± 7 and 420 ± 120 K, respectively. This two-folded rotational temperature suggests that the absorbing gas is located beyond ≃ 0 · " 4 ≃ 20 R ⋆ from the star with a noticeable cold contribution outwards from ≃ 10″ ≃ 500R⋆. This outer shell matches up with the place where cyanoacetylenes and carbon chains are known to form due to the action of the Galactic dissociating radiation field on the neutral gas coming from the inner layers of the envelope.

[Update pulmonary arterial hypertension : Definitions, diagnosis, therapy]

The term pulmonary arterial hypertension comprises a group of pulmonary vascular diseases of different etiologies that are characterized by similar precapillary vascular remodeling processes and result in exertional dyspnea and right heart insufficiency. The specific pharmacological treatment approach considers the risk of mortality and phenotypical properties and includes treatment with phosphodiesterase type 5 inhibitors, endothelin receptor antagonists and prostanoids, as well as with more novel substances, such as a soluble guanylyl cyclase stimulator and an oral prostacyclin receptor agonist. The prognosis of the disease is mainly determined by the right heart insufficiency for which there is currently no specific pharmacological treatment. Lung transplantation may be offered as a last option. This review provides an overview of the current European guidelines from 2015 and the recommendations of the Cologne Consensus Conference for pulmonary hypertension from 2016.

The Abundance of C2H4 in the Circumstellar Envelope of IRC+10216

High spectral resolution mid-IR observations of ethylene (C2H4) towards the AGB star IRC+10216 were obtained using the Texas Echelon Cross Echelle Spectrograph (TEXES) at the NASA Infrared Telescope Facility (IRTF). Eighty ro-vibrational lines from the 10.5 µm vibrational mode ν7 with J ≲ 30 were detected in absorption. The observed lines are divided into two groups with rotational temperatures of 105 and 400 K (warm and hot lines). The warm lines peak at ≃ -14 km s-1 with respect to the systemic velocity, suggesting that they are mostly formed outwards from ≃ 20R⋆. The hot lines are centered at -10 km s-1 indicating that they come from a shell between 10 and 20R⋆. 35% of the observed lines are unblended and can be fitted with a code developed to model the emission of a spherically symmetric circumstellar envelope. The analysis of several scenarios reveal that the C2H4 abundance relative to H2 in the range 5 - 20R⋆ is 6.9 × 10-8 in average and it could be as high as 1.1 × 10-7. Beyond 20R⋆, it is 8.2 × 10-8. The total column density is (6.5 ± 3.0) × 1015 cm-2. C2H4 is found to be rotationally under local thermodynamical equilibrium (LTE) and vibrationally out of LTE. One of the scenarios that best reproduce the observations suggests that up to 25% of the C2H4 molecules at 20R⋆ could condense onto dust grains. This possible depletion would not influence significantly the gas acceleration although it could play a role in the surface chemistry on the dust grains.

Circulating Angiopoietin-1 Is Not a Biomarker of Disease Severity or Prognosis in Pulmonary Hypertension

Background

Circulating angiopoietin-1 (Ang-1) has been linked to pulmonary hypertension (PH) in experimental studies. However, the clinical relevance of Ang-1 as a biomarker in PH remains unknown. We aimed to investigate the prognostic and clinical significance of Ang-1 in PH using data from the prospectively recruiting Giessen PH Registry.

Methods

Patients with suspected PH (without previous specific pulmonary arterial hypertension [PAH] therapy) who underwent initial right heart catheterization (RHC) in our national referral center between July 2003 and May 2012 and who agreed to optional biomarker analysis were included if they were diagnosed with idiopathic PAH, connective tissue disease-associated PAH (CTD-PAH), PH due to left heart disease (PH-LHD), or chronic thromboembolic PH (CTEPH), or if PH was excluded by RHC (non-PH controls). The association of Ang-1 levels with disease severity (6-minute walk distance and pulmonary hemodynamics) was assessed using linear regression, and the impact of Ang-1 levels on transplant-free survival (primary endpoint) and clinical worsening was assessed using Kaplan—Meier curves, receiver operating characteristic (ROC) analyses, and Cox regression.

Results

151 patients (39, 39, 32, and 41 with idiopathic PAH, CTD-PAH, PH-LHD, and CTEPH, respectively) and 41 non-PH controls were included. Ang-1 levels showed no significant difference between groups (p = 0.8), and no significant associations with disease severity in PH subgroups (p ≥ 0.07). In Kaplan—Meier analyses, Ang-1 levels (stratified by quartile) had no significant impact on transplant-free survival (p ≥ 0.27) or clinical worsening (p ≥ 0.51) in PH subgroups. Regression models found no significant association between Ang-1 levels and outcomes (p ≥ 0.31). ROC analyses found no significant cut-off that would maximize sensitivity and specificity.

Conclusions

Despite a strong pathophysiological association in experimental studies, this first comprehensive analysis of Ang-1 in PH subgroups suggests that Ang-1 is not a predictive and clinically relevant biomarker in PH.

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

Background

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

Methods

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

Results

Thirty-seven patients (of 116 patients screened) with mPAP of 43.2 ± 8.7 mmHg, pulmonary vascular resistance (PVR) of 605.5 ± 228.7 dyn*s/cm⁵, cardiac index (CI) of 2.4 ± 0.5 l/min/m² and a 6MWT-distance of 404.7 ± 148.4 m and a peak VO₂ of 12.3 ± 3.4 ml/min/kg prior to PEA were included. Baseline ΔHR during 6MWT was significantly associated with PVR 1 year post-PEA using linear regression analysis (r = 0.43, p = 0.01). Multivariate analysis indicated an association of HRR during 6MWT and residual PH with a hazard ratio of 1.06 (95 % Confidence interval for hazard ratio 0.99–1.14, p = 0.08). EID was observed commonly during 6MWT but no correlations to outcome parameters were found.

Conclusions

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

The prognostic relevance of oxygen uptake in inoperable chronic thromboembolic pulmonary hypertension

BACKGROUND

Patients with chronic thromboembolic pulmonary hypertension (CTEPH) present with a decreased oxygen uptake, however, the prognostic relevance of oxygen uptake (VO₂ ) in inoperable CTEPH is unknown.

METHODS

Patients with inoperable CTEPH were retrospectively analyzed. All patients were assessed by means of right heart catheterisation and cardio pulmonary exercise testing in semisupine position with a 30 Watt increment step-protocol.

RESULTS

One-hundred and fifty-one patients (82 female (54.3%), mean age 61 ± 12.4 years) presented with a mean pulmonary arterial pressure of 40.2 ± 14.2 mmHg and pulmonary vascular resistance (PVR) of 641.9 ± 374.8 dyne∗s/cm⁵ . The peak VO₂ (mean 13.1 ± 4.5 mL∗kg^-1 ∗min^-1 ) was measured at initial referral. Over a follow-up of up to 10 years (mean 4.41 ± 2.57 years), 31 patients had died. Patients with a baseline peak VO₂  ≥ 10.7 mL∗kg^-1 ∗min^-1 [area under the receiver-operating characteristic curve (AUC) = 0.728, P = 0.001] had better survival than those with a peak VO₂  ≤ 10.7 mL∗kg^-1 ∗min^-1 using Kaplan-Meier analysis (88.8% vs 60.1%; log rank P = 0.001). Adjusting for age, gender and PVR, multivariate analysis identified peak VO₂ as a predictor of mortality [hazard ratio (HR): 2.78, 95% CI 1.01-7.63, P = 0.047]. In addition, peak VO₂ failed as an independent prognostic factor in a stepwise multivariate model including all variables significant in the univariate analysis.

CONCLUSIONS

In patients with inoperable CTEPH the peak VO₂ is a significant predictor of survival, when adjusting for age, gender and PVR. However, peak VO₂ failed as an independent prognostic factor when correcting for all significant baseline variables, which is limiting the clinical usability.

Pulmonary Hemodynamic Response to Exercise in Chronic Thromboembolic Pulmonary Hypertension before and after Pulmonary Endarterectomy

BACKGROUND

Pulmonary endarterectomy (PEA) is the treatment of choice in surgically accessible chronic thromboembolic pulmonary hypertension (CTEPH). An important predictor of outcome is postsurgical residual pulmonary hypertension.

OBJECTIVE

We aimed to use the hemodynamic response during exercise before PEA as a measurement for the hemodynamic outcome 1 year after PEA.

METHODS

Between January 2011 and December 2013, 299 patients underwent PEA in our center. A total of 16 patients who were assessed by means of invasive hemodynamic measurements during exercise both at baseline and 1 year after PEA were retrospectively analyzed.

RESULTS

Pre-PEA mean pulmonary arterial pressure (mPAP) increased during exercise from 35.8 ± 7.6 to 53.8 ± 5.1 mm Hg, diastolic pulmonary arterial pressure (dPAP) from 21.5 ± 5.6 to 30.3 ± 9.6 mm Hg, cardiac output (CO) from 4.4 ± 0.8 to 6.5 ± 1.9 l/min and diastolic pulmonary gradient (DPG) from 14.6 ± 4.9 to 20.7 ± 12.7 mm Hg. Post-PEA mPAP increased from 23.7 ± 6.6 at rest to 43.2 ± 7.1 mm Hg, while CO increased to a higher extent from 5.1 ± 0.9 to 8.4 ± 1.9 l/min. There were significant correlations between pre-PEA DPG/CO and dPAP/CO slopes with the pulmonary vascular resistance (Spearman r = 0.578, p = 0.019, and r = 0.547, p = 0.028) and mPAP at rest after PEA (Spearman r = 0.581, p = 0.018, and r = 0.546, p = 0.028).

CONCLUSIONS

In CTEPH, the presurgical dynamic DPG/CO and dPAP/CO slopes during submaximal exercise are associated with the hemodynamic outcome 1 year after PEA.

[Medical treatment of pulmonary hypertension: what's new?]

Pulmonary hypertension (PH) is a chronic progressive disease of the pulmonary circulation of multifactorial causes. The current diagnostic classification of PH distinguishes five main groups, which have as a common feature an increased pulmonary arterial pressure and pulmonary resistance. The classification differentiates pulmonary arterial hypertension (PAH), PH due to left heart disease, PH in lung diseases and/or hypoxia, chronic thromboembolic pulmonary hypertension (CTEPH), and PH with unclear/multifactorial mechanisms. Recent advances in basic research with the approval of new drugs and the establishment of therapeutic strategies, mainly in PAH and CTEPH, require a differentiated view of the disease, a careful diagnosis and initiation of therapy, and regular follow-ups. In this article, we provide an overview of the complex drug therapy currently available for PAH patients.

[Dynamic hyperinflation in pulmonary arterial hypertension: "hyperinflator" and "non-hyperinflator"]

BACKGROUND

The dynamic decrease in inspiratory capacity (IC) during exercise with restriction of tidal volume (VT) is known as dynamic hyperinflation (DH) and is described mostly in patients with COPD differentiating between a "hyperinflator" and a "non-hyperinflator". Recent studies have revealed DH in patients with idiopathic pulmonary arterial hypertension (iPAH), but the influence of the DH on the reduced exercise capacity with exertional dyspnoae is still being debated.

METHODS

We analysed flow-volume curves during cardiopulmonary exercise testing (CPET) in idiopathic PAH (n = 19), in COPD (n = 17), in idiopathic pulmonary fibrosis (IPF) (n = 19) and a control group (n = 30). We measured IC at rest and during maximal exercise and furthermore ventilation, VT and oxygen uptake (VO2 peak). In iPAH a right heart catheter test and a 6-minute walk test (6MWT) were performed, also the B-type naturetic peptide (BNP) and the NYHA/WHO functional class were determined.

RESULTS

The IC decreased significantly in 11 PAH "hyperinflators" (PAH-H) (Δ IC: - 0.34 ± 0.14 L, p < 0.001) compared to 8 PAH "non-hyperinflators" (PAH-NH) (Δ IC: 0.08 ± 0.2 L). COPD patients exhibited a characteristic hyperinflation pattern with a decrease in IC throughout exercise (Δ IC: - 0.61 ± 0.3 L, p < 0.001), while patients with IPF (Δ IC: 0.03 ± 0.15 L) and the control group responsed to exercise with a non-hyperinflator pattern (Δ IC: 0.1 ± 0.2 L). Both PAH collectives showed a reduced IC/TLC, while VT/IC was elevated with a decreased peak VO2 and max. performance compared to the control group. Correlations of the IC rest/max (L) were shown in PAH-H and PAH-NH with the VO2 peak, max. performance and VT.

CONCLUSION

The analysis of flow-volume curves during CPET can indentify DH in a subgroup of patients with iPAH. The DH contributes significantly but slightly to the development of exertional limitations and dyspnoe in a subgroup of iPAH. Further studies with a larger sample size will be required to definitively measure the impact of the DH seen in these patients.

[Chylothorax in an 87-year-old patient]

An 87-year-old woman presented with a left-sided pleural effusion. The milky aspirate fulfilled the criteria of a chylothorax. Thorax computed tomography (CT) showed characteristic multiple cysts and consequently the rare diagnosis of post-menopausal pulmonary lymphangioleiomyomatosis was made. In the diagnostic work-up of pleural effusion the determination of triglycerides should be considered to confirm the diagnosis of chylothorax. In the presence of a chylothorax the differential diagnosis of lymphangioleiomyomatosis should be included even in advanced age.

Similarity measure for quality control of dental CAD/CAM-applications

There is no measure for morphometric quality control of dental CAD/CAM-restorations as well as for evaluation of newly developed CAD/CAM-applications. The aim of this study was to (a) establish a 3D-measure for morphological comparisons, (b) to proof its metrical and subjective-visual validity and (c) to explore morphological features which have relevant impact on visual perception. 125 maxillary anterior teeth were chosen from a digital library of 3D data sets and compared by automatic superimposition with a best-fit method. The superimposition was analyzed by a newly defined 3-dimensional similarity measure, called shape similarity value (SSV). With this measure, similarity between symmetrical and non-symmetrical teeth was evaluated and the metrical validity was tested. Additionally, visual evaluation of tooth similarities were performed and analyzed by means of multivariate statistical procedures, to test the correspondence between metrical similarity measure and visual similarity perception. The measure clearly reproduced the similarity of contralateral teeth and the dissimilarity of teeth between different individuals. The coincidence between quantitative similarity measure and visual perception was moderate. In conclusion, the presented 3D-measure can be considered as a first substantial step towards a morphometric quality control of CAD/CAM-restorations of anterior teeth.

In vivo studies on flexion and extension of the lumbar spine after stabilisation with a non-fusion pedicle screw system

OBJECTIVE: The aim was to determine in vivo whether pre-operative mobility of the lumbar spine (overall and segmental) is retained after surgical intervention. METHODS: Functional imaging of the lumbar spine was performed in flexion and extension, using a lateral projection under standardised conditions. This allowed assessment of the overall mobility, mobility of the instrumented mobile segments and the disc height of the adjacent cranial segment (intervertebral space; IVS) before and after surgical intervention. Images were evaluated independently by a radiologist and an orthopaedic surgeon. A comparative analysis of preoperative and postoperative functional images was carried out with the aid of a computer and appropriate software (ACES) for further assessment of the extent to which the range of movement was retained. The Oswestry Disability Index (ODI, quality of life assessment) and the visual analogue scale (VAS, pain assessment) were used as clinical criteria and compared pre-and postoperatively. The mean follow-up (FU) intervals were 13.5 days (FU 1) and 19 months (FU 2). RESULTS: Radiological results showed that the overall mobility of the lumbar spine (L1 to S1) decreased on average by one third of the flexion/extension range, from 25.0º preoperatively to 17.6º postoperatively. The segmental mobility of the monosegmental stabilisation decreased on average from 3.7º to 2.3º. The caudal segments of the bisegmental dynamic stabilisation retained their preoperative movement range of 2.6º, with a postoperative range of 2.4º. The IVS did not change. The ODI improved postoperatively from 59 (preoperative) to 39/41 (FU1/FU2) points, while the VAS (during movement) improved from 7.6 (pre-op) to 4.4/4.5 (FU1/FU2). Computer-assisted analysis showed that small and functionally insignificant micro-motion of 0.4º (error 0.12%) remained in the stabilised and unfused mobile segment. CONCLUSION: Comparison of preoperative and postoperative measurements showed that overall mobility and segmental micro-motion were retained after non-fusion stabilisation of the lumbar spine with monosegmental and bisegmental instrumentation. The adjacent cranial segment (IVS) did not collapse. Activity levels (ODI) and pain symptoms (VAS) of the patients showed significant improvement at follow-up, comparable to that reported in the literature for conventional rigid spinal fusions.

Nutritional value of diets of blacks in Ciskei

This dietary study was part of a nutritional status survey carried out at the request of the Ciskeian Government to provide a baseline from which to formulate a nutrition policy. Nutrient intake was assessed by means of a 24-hour recall of food intake and a diet history, recorded for 750 subjects including children aged 6-23 months, 2-3 years and 7-8 years and lactating women. Nutrient intake was evaluated according to WHO standards. The prevalence of inadequate energy intake was high, especially among the 7-8-year-old children. For all age groups protein represented 11% of total energy intake, but was mainly of low quality. Calcium and iron intakes were low in all age groups, especially in lactating women. For all groups the most deficient vitamin was nicotinic acid, followed by riboflavin and ascorbic acid. This deficiency pattern was the result of a diet consisting predominantly of maize.