Atrial fibrillation-specific refinement of the STOP-Bang sleep apnoea screening questionnaire: insights from the Virtual-SAFARI study.

BACKGROUND: Sleep-disordered breathing (SDB) is prevalent in up to 50% of patients referred for atrial fibrillation (AF) catheter ablation (CA). Currently, it remains unclear how to improve pre-selection for SDB screening in patients with AF. AIM: We aimed to (1) assess the accuracy of the STOP-Bang screening questionnaire for detection of SDB within an AF population referred for CA; (2) derive a refined, AF-specific SDB score to improve pre-selection. METHODS: Consecutive AF patients referred for CA without a history of SDB and/or SDB screening were included. Patients were digitally referred to the previously implemented Virtual-SAFARI SDB screening and management pathway including a home sleep test. An apnoea-hypopnoea index (AHI) of  ≥ 15 was interpreted as moderate-to-severe SDB. Logistic regression analysis was used to assess characteristics associated with moderate-to-severe SDB to refine pre-selection for SDB screening. RESULTS: Of 206 included patients, 51% were diagnosed with moderate-to-severe SDB. The STOP-Bang questionnaire performed poorly in detecting SDB, with an area under the receiver operating characteristic curve (AUROC) of 0.647 (95% Confidence-Interval (CI) 0.573-0.721). AF-specific refinement resulted in the BOSS-GAP score. Therein, BMI with cut-off point ≥ 27 kg/m2 and previous stroke or transient ischaemic attack (TIA) were added, while tiredness and neck circumference were removed. The BOSS-GAP score performed better with an AUROC of 0.738 (95% CI 0.672-0.805) in the overall population. CONCLUSION: AF-specific refinement of the STOP-Bang questionnaire moderately improved detection of SDB in AF patients referred for CA. Whether questionnaires bring benefits for pre-selection of SDB compared to structural screening in patients with AF requires further studies. TRIAL REGISTRATION NUMBER: ISOLATION was registered NCT04342312, 13-04-2020.

A VIRTUAL Sleep Apnoea management pathway For the work-up of Atrial fibrillation patients in a digital Remote Infrastructure: VIRTUAL-SAFARI.

AIMS: In atrial fibrillation (AF) patients, untreated sleep-disordered breathing (SDB) is associated with lower success rates of rhythm control strategies and as such structured SDB testing is recommended. Herein, we describe the implementation of a virtual SDB management pathway in an AF outpatient clinic and examine the utility and feasibility of this new approach. METHODS AND RESULTS: Prospectively, consecutive AF patients accepted for AF catheter ablation procedures without previous diagnosis of SDB were digitally referred to a virtual SDB management pathway and instructed to use WatchPAT-ONE (ITAMAR) for one night. Results were automatically transferred to a virtual sleep laboratory, upon which a teleconsultation with a sleep physician was planned. Patient experience was measured using surveys. SDB testing was performed in 119 consecutive patients scheduled for AF catheter ablation procedures. The median time from digital referral to finalization of the sleep study report was 18 [11-24] days. In total, 65 patients (55%) were diagnosed with moderate-to-severe SDB. Patients with SDB were prescribed more cardiovascular drugs and had higher body mass indices (BMI, 29 ± 3.3 vs. 27 ± 4.4kg/m2, P < 0.01). Patients agreed that WatchPAT-ONE was easy to use (91%) and recommended future use of this virtual pathway in AF outpatient clinics (86%). Based on this remote SDB testing, SDB treatment was recommended in the majority of patients. CONCLUSION: This novel virtual AF management pathway allowed remote SDB testing in AF outpatient clinics with a short time to diagnosis and high patient satisfaction. Structured SDB testing results in a high detection of previously unknown SDB in AF patients scheduled for AF ablation.

Changes in lung function among treated HIV-positive and HIV-negative individuals: analysis of the prospective AGEhIV cohort study.

BACKGROUND: The AGEhIV cohort study is a prospective cohort study evaluating the occurrence of age-related comorbidities in people living with and without HIV. We previously reported a lower forced vital capacity (FVC) in HIV-positive compared with HIV-negative participants in those without heavy smoking exposure at time of enrolment in the AGEhIV cohort study. In this study we evaluate longitudinal changes in spirometry indices in the same AGEhIV cohort accounting for smoking behaviour and other risk factors. METHODS: We obtained pre-bronchodilator spirometry measurements in AGEhIV cohort participants during biennial visits over a median of 5·9 years (IQR 5·7-6·0). Adjusted declines in forced expiratory volume in 1 s (FEV1), FVC, and FEV1/FVC ratio were modelled using linear mixed-effects models and compared by HIV status and smoking status. To evaluate whether changes in spirometry measurements could be driven by increased levels of chronic inflammation, we assessed associations between rates of FEV1 and FVC decline and CD4 and CD8 T-cell counts, and plasma concentrations of C-reactive protein (CRP), interleukin 6, soluble CD14, soluble CD163, and intestinal fatty-acid-binding protein in separate models. The study is registered at ClinicalTrials.gov, NCT01466582. FINDINGS: 500 HIV-positive and 481 HIV-negative participants were included with spirometry data from Oct 29, 2010, to Aug 14, 2018. HIV-positive participants were virally suppressed (<40 copies per mL) during 1627 (95%) study visits, and 159 (32%) HIV-positive and 183 (38%) HIV-negative participants had never smoked. Adjusted declines in FEV1 were 10·0 mL per year faster in HIV-positive non-smokers (95% CI 4·2 to 15·7, p=0·00066) compared with HIV-negative non-smokers, and 11·1 mL per year faster in HIV-positive smokers (95% CI 0·7 to 21·4, p=0·036) compared with HIV-negative smokers. In comparison, smoking was associated with a 16·4 mL per year steeper decline in FEV1 among HIV-positive participants (95% CI 8·0 to 24·7, p=0·00012), and 15·3 mL per year steeper decline among HIV-negative participants (95% CI 6·7-24·0, p=0·00052) compared with not smoking. Adjusted yearly declines in FEV1 and FVC, but not FEV1/FVC, were significantly greater in HIV-positive than HIV-negative participants overall (additional decline in HIV-positive participants, FEV1 10·5 mL per year [95% CI 4·7 to 16·3], p=0·00040; FVC 11·5 mL per year [2·8 to 20·3], p=0·0096; FEV1/FVC 0·07% per year [-0·05 to 0·19], p=0·26), with a similar observation for never-smokers (FEV1 6·0 mL per year [-1·8 to 13·7], p=0·13; FVC 9·1 mL per year [-3·0 to 21·1], p=0·14; FEV1/FVC ratio 0·00% per year [-0·18 to -0·18], p=0·97). Higher CRP concentrations during follow-up were associated with accelerated declines in FEV1 and FVC among HIV-positive participants but not among HIV-negative participants. INTERPRETATION: Treated HIV infection was associated with faster declines in both FEV1 and FVC, but not in the FEV1/FVC ratio. These changes were independent of smoking and might have been driven by ongoing interstitial or small airway damage, potentially related to increased inflammation. FUNDING: ZonMW, Aidsfonds, Gilead Sciences, ViiV Healthcare, Janssen Pharmaceuticals, Merck.

Impact of atrial septal defect closure on diffusing capacity for nitric oxide and carbon monoxide.

Atrial septal defects are characterised by a low D LNO /D LCOc ratio in diffusion testing. Successful percutaneous closure shows an increase in D LNO /D LCOc ratio and vital capacity through correction of a hyperdynamic pulmonary circulation. http://ow.ly/Rqkc30o5yMM.

Reduced Forced Vital Capacity Among Human Immunodeficiency Virus-Infected Middle-Aged Individuals.

BACKGROUND: Pulmonary function impairments are more common among people living with HIV (PLWH), as are contributing risk behaviors. To understand the effects of human immunodeficiency virus (HIV) infection independent of risk behaviors, pulmonary function was evaluated in lifestyle-comparable HIV-infected and -uninfected AGEhIV cohort participants. METHODS: Prevalence of obstructive lung disease in 544 HIV-infected and 529 HIV-uninfected participants was determined using spirometry. Logistic regression was used to assess HIV as a determinant of obstructive lung disease. Additional explanatory models were constructed to explain observed differences. RESULTS: The unadjusted obstructive lung disease prevalence was similar in HIV-infected (23.0%) and -uninfected (23.4%) participants. Multivariable logistic regression analysis showed an effect modification whereby obstructive lung disease prevalence among persons with limited smoking experience was notably lower among HIV-infected compared with HIV-uninfected participants. This resulted from a lower forced vital capacity (FVC) in HIV-infected participants but similar 1-second forced expiratory volume (FEV1), especially in those with limited smoking experience. CONCLUSIONS: The lower FVC in HIV-infected participants could indicate HIV-related restrictive or fibrotic pulmonary changes. Factors that decrease the FVC could obscure emphysematous changes in the lungs of PLWH when using the FEV1/FVC ratio as single diagnostic measure. CLINICAL TRIALS REGISTRATION: NCT01466582.

Use of Pulmonary Inhalants Remains Remarkably High After Atrial Septal Defect Closure.

BACKGROUND: Post-repair atrial septal defects (ASD) patients are frequently discharged from follow-up, but the extent of pulmonary symptoms long-term post-repair is unknown. Methods and Results: The national CONgenital CORvitia registry was linked to the national Drug Registry to investigate all ambulatory-dispensed pulmonary inhalants for 2006-2014. ASD patients were compared with age- and sex-matched referents from the general population. A total of 1,959 adult patients (age 42±17 years; 66% female; 1,223 [62%] repaired) were included. Compared with the referents, ASD patients had more inhalant use, even at long-term post-repair follow-up (OR=1.81 [95% CI 1.62-2.03]; P<0.001). CONCLUSIONS: ASD patients had 2-fold higher inhalant use compared with referents even at long-term post-repair follow-up, suggesting persistent pulmonary functional impairment.

Atrial septal defect in adults is associated with airway hyperresponsiveness.

OBJECTIVE: The association between secundum atrial septal defects (ASD) and asthma-like dyspnea with consequent long-term pulmonary inhalant use, is poorly understood in adult ASD patients. Airway hyperresponsiveness is suggested to be the underlying mechanism of cardiac asthma from mitral valve disease and ischemic cardiomyopathy. We hypothesized that airway hyperresponsiveness may also be found in adult ASD patients. Our aim was to study airway responsiveness in adult ASD patients before percutaneous closure and at short-and long-term postprocedural follow-up. METHODS: This prospective study included 31 ASD patients (65% female, mean age 49 ± 15y) who underwent spirometry and bronchoprovocation testing pre-and six-month postprocedurally, with additional bronchoprovocation at 2-year follow-up. Airway hyperresponsiveness was defined as ≥20% fall of forced expiratory volume in 1-second (FEV1 ) following <8.0 mg/mL of inhaled methacholine. RESULTS: Airway hyperresponsiveness was found in 19/30 patients (63%[95%CI 45%-81%]; post hoc statistical power = 89%). Asthma-like symptoms wheezing, chest tightness, and cough were more frequently reported in airway hyperresponsive patients. Airway responsiveness was not influenced by successful percutaneous ASD closure, corresponding to persistence of asthma-like symptoms postclosure. Regardless of airway responsiveness, postprocedural right-sided reverse remodeling significantly improved dyspnea and pulmonary function. CONCLUSIONS: This study is the first to report a high prevalence of airway hyperresponsiveness in a cohort of unrepaired adult ASD patients, and confirms the association between asthma-like symptoms and ASD in adults. Attention to symptoms and pulmonary function should be given during clinical follow-up of adult ASD patients, both before and long after repair.

Hemodynamic and ventilatory responses during exercise in chronic thromboembolic disease.

BACKGROUND: Patients with chronic thromboembolic disease (CTED) may suffer from exercise intolerance without pulmonary hypertension at rest. Pulmonary endarterectomy (PEA) for symptomatic CTED results in improvement of symptoms and quality of life. Neither the pathophysiology of the exercise limitation nor the underlying mechanisms of the PEA-induced improvement have been studied previously. OBJECTIVES: We studied hemodynamic and ventilatory responses upon exercise in 14 patients with CTED. After 1 year, we studied the underlying physiologic mechanisms of the PEA-induced symptomatic improvement. METHODS: Cardiopulmonary exercise testing (CPET) was performed during right heart catheterization, and noninvasive CPET was performed 1 year postoperatively. RESULTS: During exercise, we observed abnormal pulmonary vascular responses, that is, a steep mean pulmonary artery pressure/cardiac output (2.7 ± 1.2 mm Hg·min·L(-1)), and low pulmonary vascular compliance (2.8 ± 1.1 mL·mm Hg(-1)); mean pulmonary artery pressure/cardiac output slope correlated with dead-space ventilation (r = 0.586; P = .028) and ventilatory equivalents for carbon dioxide slope (r = .580; P = .030). Postoperatively, the improvement observed in exercise capacity was related to improvements in CPET-derived parameters pointing to restoration of right ventricle stroke volume response (oxygen pulse: 11.7 ± 3.1 to 13.3 ± 3.3; P = .027; heart rate response: 80.9 ± 12.4 to 72.0 ± 5.7; P = .003); and, indicating improved ventilatory efficiency, the ventilatory equivalents for carbon dioxide slope decreased from 38.2 ± 3.6 to 32.8 ± 7.0 (P = .014). CONCLUSIONS: Patients with CTED showed an abnormal pulmonary vascular response to exercise and a decreased ventilatory efficiency. Responses after PEA point to restoration of right ventricle stroke volume response and ventilatory efficiency.

Exercise tolerance, lung function abnormalities, anemia, and cardiothoracic ratio in sickle cell patients.

Many patients with sickle cell disease (SCD) have a reduced exercise capacity and abnormal lung function. Cardiopulmonary exercise testing (CPET) can identify causes of exercise limitation. Forty-four consecutive SCD patients (27 HbSS, 11 HbSC, and 6 HbS-beta thalassemia) with a median age (interquartile range) of 26 (21-41) years underwent pulmonary function tests, CPET, chest x-ray, and echocardiography to further characterize exercise limitation in SCD. Peak oxygen uptake (V'O2 -peak), expressing maximum exercise capacity, was decreased in 83% of the studied patients. V'O2 -peak correlated with hemoglobin levels (R = 0.440, P = 0.005), forced vital capacity (FVC) (R = 0.717, P < 0.0001). Cardiothoracic ratio on chest x-ray inversely correlated with FVC (R = -0.637, P < 0.001). According to criteria for exercise limitation, the patients were limited in exercise capacity due to anemia (n = 17), cardiovascular dysfunction (n = 2), musculoskeletal function (n = 10), pulmonary ventilatory abnormalities (n = 1), pulmonary vascular exercise limitation (n = 1), and poor effort (n = 3). In the present study we demonstrate that anemia is the most important determinant of reduced exercise tolerance observed in SCD patients without signs of pulmonary hypertension. We found a strong correlation between various parameters of lung volume and cardiothoracic ratio and we hypothesize that cardiomegaly and relative small chest size may be important causes of the impairment in pulmonary function, that is, reduced long volumes and diffusion capacity, in SCD. Taking into account anthropomorphic differences between SCD patients and controls could help to interpret lung function studies in SCD better.

Antimicrobial susceptibility of Streptococcus pneumoniae in adult patients with pneumococcal pneumonia in an urban hospital in Mozambique.

BACKGROUND: Streptococcus pneumoniae is the leading cause of community-acquired pneumonia in Africa. Antimicrobial resistance of S. pneumoniae to penicillin and other commonly used antibiotics has increased worldwide. However, prevalence data from the African region are sparse, especially with regard to adults. FINDINGS: In this study, adult patients presenting at an urban referral hospital in central Mozambique were screened for pneumococcal pneumonia during an 8-week period in 2010: Patients with a respiratory syndrome underwent chest radiography and a sputum sample was collected for pneumococcal culture and antimicrobial susceptibility testing. A urine sample was tested for the presence of pneumococcal antigen.177 patients with a respiratory syndrome were included. Overall, 41/177 (23%) patients fulfilled criteria for definite or probable pneumococcal pneumonia and in the group of patients with a positive chest x-ray this concerned 35/86 (41%) patients. 166 sputum cultures yielded 16 pneumococcal strains. One mg oxacillin disc testing identified potential penicillin resistance in 7/16 (44%) strains. Penicillin minimal inhibitory concentrations (MICs) were measured for 15 of these strains and ranged from <0.016-0.75 mg/L. No MICs >2 mg/L were found, but 3/15 (20%) pneumococcal strains had MICs >0.5 mg/L. All pneumococci were sensitive to erythromycin as measured by disc diffusion testing, whereas 44% was resistant to trimethoprim-sulfametoxazole. CONCLUSIONS: The proportion of pneumonia cases attributable to pneumococcus appeared to be high. Whilst none of the S. pneumoniae strains tested were penicillin resistant, standard penicillin dosing for pneumonia may be insufficient given the observed range of pneumococcal penicillin MICs.

[Dysphagia in a young woman from Somalia]. / Dysfagie bij jonge vrouw uit Somalië

BACKGROUND: Multidrug-resistant tuberculosis is increasing worldwide. The determination of possible resistance is essential for adequate treatment. Tuberculosis is common amongst immigrants from Somalia and extra-pulmonary localisation is often seen. CASE DESCRIPTION: A 21-year-old woman from Somalia presented with progressive dysphagia and severe weight loss. Endoscopy revealed two ulcers in the mid-oesophagus. A chest x-ray showed enlarged lymph nodes in the right hilar and mediastinal regions. The Ziehl-Neelsen stain and PCR for mycobacteria were negative. Sputum samples and oesophageal biopsies were cultured. Quadruple tuberculostatic therapy was started empirically. After five weeks, a sputum culture grew Mycobacterium tuberculosis, which was resistant to rifampicin and isoniazid. She was treated with second-line anti-tuberculous therapy and eventually recovered. CONCLUSION: Tuberculosis can manifest in many ways. It is important to obtain patient material for culture; not only to confirm the diagnosis but also for the determination of possible resistance which is necessary for adequate therapy.

Longitudinal follow-up of six-minute walk distance after pulmonary endarterectomy.

BACKGROUND: The 6-minute walk test is a useful tool to assess functional outcome after pulmonary endarterectomy (PEA) in chronic thromboembolic pulmonary hypertension. However, little is known about the longitudinal dynamics in functional improvement. We performed a longitudinal follow-up of 6-minute walk distance, New York Heart Association functional class, and echocardiography after PEA. METHODS: We studied 71 patients with chronic thromboembolic pulmonary hypertension who underwent PEA. A 6-minute walk test and echocardiography were performed before PEA, at 3 months after, and at annual follow-up. At the time of this report, 52 patients had returned for 2-year follow-up, 32 for 3-year follow-up, 23 for 4-year follow-up, and 11 for 5-year follow-up. RESULTS: Preoperatively, the 6-minute walk distance (6-MWD) correlated with hemodynamic severity of disease (mean pulmonary artery pressure: r = -0.55, p < 0.001); total pulmonary resistance: r = -0.59, p < 0.001) After PEA, 6-MWD increased from 440 ± 109 to 524 ± 83 meters at 1 year (n = 71, p < 0.001). Further improvement was observed from 523 ± 87 meters at 1 year to 536 ± 91 meters at 2 years (n = 52, p < 0.012). After 2 years, no further improvement was observed. At 1 year, the change in 6-MWD from baseline correlated significantly with the change observed in pulmonary hemodynamics. Changes in 6-MWD and hemodynamics were more pronounced in patients with residual pulmonary hypertension after PEA, despite the worse absolute outcome. CONCLUSIONS: In patients with chronic thromboembolic pulmonary hypertension, 6-MWD showed a gradual improvement up to 2 years after PEA. Patients with residual pulmonary hypertension benefited most from treatment, despite the worse absolute outcome.

Airway inflammation and mannitol challenge test in COPD.

BACKGROUND: Eosinophilic airway inflammation has successfully been used to tailor anti-inflammatory therapy in chronic obstructive pulmonary disease (COPD). Airway hyperresponsiveness (AHR) by indirect challenges is associated with airway inflammation. We hypothesized that AHR to inhaled mannitol captures eosinophilia in induced sputum in COPD. METHODS: Twenty-eight patients (age 58 ± 7.8 yr, packyears 40 ± 15.5, post-bronchodilator FEV1 77 ± 14.0%predicted, no inhaled steroids ≥4 wks) with mild-moderate COPD (GOLD I-II) completed two randomized visits with hypertonic saline-induced sputum and mannitol challenge (including sputum collection). AHR to mannitol was expressed as response-dose-ratio (RDR) and related to cell counts, ECP, MPO and IL-8 levels in sputum. RESULTS: There was a positive correlation between RDR to mannitol and eosinophil numbers (r = 0.47, p = 0.03) and level of IL-8 (r = 0.46, p = 0.04) in hypertonic saline-induced sputum. Furthermore, significant correlations were found between RDR and eosinophil numbers (r = 0.71, p = 0.001), level of ECP (r = 0.72, p = 0.001), IL-8 (r = 0.57, p = 0.015) and MPO (r = 0.64, p = 0.007) in sputum collected after mannitol challenge. ROC-curves showed 60% sensitivity and 100% specificity of RDR for >2.5% eosinophils in mannitol-induced sputum. CONCLUSIONS: In mild-moderate COPD mannitol hyperresponsiveness is associated with biomarkers of airway inflammation. The high specificity of mannitol challenge suggests that the test is particularly suitable to exclude eosinophilic airways inflammation, which may facilitate individualized treatment in COPD. TRIAL REGISTRATION: Netherlands Trial Register (NTR): NTR1283.

Fibrotic idiopathic interstitial pneumonias: mortality is linked to a decline in gas transfer.

BACKGROUND AND OBJECTIVE: Baseline clinical and physiological features and changes in these parameters over time are known predictors of survival in patients with fibrotic idiopathic interstitial pneumonia (IIP). Pulmonary hypertension is common in advanced fibrotic IIP, and has a negative impact on survival. Serial pulmonary function profiles, indicative of increasing vascular impairment in patients with IIP, and in particular, selective reductions in gas transfer, have not been studied previously. METHODS: Predictors of event-free survival time were investigated in a cohort of Dutch patients with IPF and fibrotic non-specific interstitial pneumonia (n = 117). Pulmonary function test data were prospectively collected from November 1993 to December 2005. Multivariate Cox regression models were developed to identify the prognostic relevance to survival of variables related to baseline demographics, histopathology, pulmonary function and the 6- and 12-month changes in pulmonary function parameters. RESULTS: Different survival patterns were observed for patients with different histopathological diagnoses. At baseline, FVC was the most important prognostic factor. At the 6-month follow up, change in transfer coefficient (K(CO), DL(CO)/V(A)), and at the 12-month follow up, age, baseline K(CO) and 12-month change in FVC and K(CO), were independent predictors of event-free survival. CONCLUSIONS: Apart from histopathology, change in K(CO) over time appeared to be the most consistent and powerful predictor of survival in these patients. The decline in K(CO) may be indicative of increasing vascular impairment, which may have a major impact on survival, in patients with fibrotic IIP.

Pulmonary endarterectomy improves dyspnea by the relief of dead space ventilation.

BACKGROUND: In chronic thromboembolic pulmonary hypertension (CTEPH), dyspnea is considered to be related to increased dead space ventilation caused by vascular obstruction. Pulmonary endarterectomy releases the thromboembolic obstruction, thereby improving regional pulmonary blood flow. We hypothesized that pulmonary endarterectomy reduces dead space ventilation and that this reduction contributes to attenuation of dyspnea symptoms. METHODS: In this follow-up study we assessed dead space ventilation, hemodynamic severity of disease, and symptomatic dyspnea in 54 consecutive CTEPH patients, before and 1 year after pulmonary endarterectomy. Dead space ventilation was calculated using the Bohr-Enghoff equation. Dyspnea was assessed by Borg scores and the New York Heart Association functional classification. RESULTS: Preoperatively, dead space ventilation was increased (0.40 +/- 0.07) and correlated with severity of disease (mean pulmonary artery pressure: r = 0.49, p < 0.001; total pulmonary resistance: r = 0.53, p < 0.001), and resting (r = 0.35, p < 0.05) and post-exercise Borg dyspnea scores (r = 0.44, p < 0.01). Postoperatively, dead space ventilation (0.33 +/- 0.08, p < 0.001) and dyspnea symptoms decreased significantly. Changes in symptomatic dyspnea were independently associated with changes in pulmonary hemodynamics and absolute dead space. CONCLUSIONS: Dead space ventilation in CTEPH is increased and correlates significantly with hemodynamic severity of disease and dyspnea symptoms. Pulmonary endarterectomy decreases dead space ventilation. The induced change in dead space upon surgical removal of chronic thromboembolism contributes to the postoperative recovery of symptomatic dyspnea.

Lung function after the minimal invasive pectus excavatum repair (Nuss procedure).

BACKGROUND: The Nuss procedure was introduced at our center in 1999. The operation was mainly performed for cosmesis. Little information is available regarding the influence of this operation on lung function. METHODS: The aim of this study, a prospective analysis, was to analyze the effect of the Nuss procedure on lung function variables. Between 1999 and 2007 a total of 203 patients with pectus excavatum were treated with the Nuss procedure, of whom 145 (104 male, 41 female) were located at Emma Children's Hospital. In the latter subset of consecutive patients, static lung function variables [total lung capacity (TLC), functional residual capacity (FRC), vital capacity (VC)] and dynamic lung function variables [forced expired volume in 1 s (FEV(1)), maximum expiratory flow (MEF(50))] were performed using spirometry and body box measurements at four time points: prior to operation (T0), 6 months after the Nuss procedure (T1, n = 111), prior to removal of the Nuss bar (T2, n = 74), and 6 months after removal (T3, n = 53). All values were expressed as a percent of normal values for sex, age, and height. Results were compared with a paired-samples t-test, with the level of significance at p = 0.05. RESULTS: At 6 months after bar insertion the TLC, FRC, VC, FEV(1), and MEF(50) showed a significant increase; and prior to bar removal the FRC and MEF(50) showed significantly increased values. At 6 months after Nuss bar removal, none of the lung function variables showed any significant change compared to the preoperative values. CONCLUSION: After the Nuss procedure for pectus excavatum, there was no improvement of pulmonary function, but neither was the patient's pulmonary function harmed by resolving a largely cosmetic problem.

Six-minute walk distance as parameter of functional outcome after pulmonary endarterectomy for chronic thromboembolic pulmonary hypertension.

OBJECTIVES: In chronic thromboembolic pulmonary hypertension, objective data to assess the functional outcome after pulmonary endarterectomy are lacking. We studied the 6-minute walk distance in relation to the clinical and hemodynamic severity of disease, and assessed the effect of pulmonary endarterectomy on the 6-minute walk distance. METHODS: A total of 50 consecutive patients with chronic thromboembolic pulmonary hypertension were studied. Subsequently, pulmonary endarterectomy was performed in 42 patients, 35 of whom underwent a 6-minute walk distance 1 year after surgery. RESULTS: The mean +/- standard error of the mean 6-minute walk distance was 391 +/- 19 m. The 6-minute walk distance decreased in proportion to New York Heart Association functional class and correlated (all P < .0001) with mean pulmonary artery pressure (r = -0.62), cardiac output (r = 0.76), total pulmonary resistance (r = -0.75), mixed venous oxygen saturation (r = 0.77), and brain natriuretic peptide (r = -0.65). One year after pulmonary endarterectomy, the 6-minute walk distance increased from 417 +/- 19 m to 517 +/- 16 m (P < .0001). The change from baseline in 6-minute walk distance correlated with the changes after 1 year in New York Heart Association functional class (P < .01) and brain natriuretic peptide (r = 0.57, P < .002), and with the observed hemodynamic changes directly after pulmonary endarterectomy (change in mean pulmonary artery pressure: r = 0.52; change in cardiac output: r = 0.70; change in total pulmonary resistance r = 0.70; all P < .001). In patients with residual pulmonary hypertension after pulmonary endarterectomy, the 6-minute walk distance was significantly lower than in hemodynamically normalized patients. However, the absolute increase in the 6-minute walk distance was higher in patients with residual pulmonary hypertension (137 +/- 26 m and 82 +/- 20 m, respectively; P = .03). CONCLUSIONS: The 6-minute walk distance was demonstrated to reflect the clinical and hemodynamic severity of disease in patients with chronic thromboembolic pulmonary hypertension. One year after pulmonary endarterectomy, the 6-minute walk distance had increased significantly, and the change in the 6-minute walk distance correlated with the observed clinical and hemodynamic improvement.