Diverging effects of premature birth and bronchopulmonary dysplasia on exercise capacity and physical activity - a case control study.

BACKGROUND: Extreme prematurity has been associated with exercise intolerance and reduced physical activity. We hypothesized that children with bronchopulmonary dysplasia (BPD) would be especially affected based on long-term lung function impairments. Therefore, the objective of this study was to compare exercise capacity and habitual physical activity between children born very and extremely preterm with and without BPD and term-born children. METHODS: Twenty-two school-aged children (aged 8 to 12 years) born with a gestational age < 32 weeks and a birthweight < 1500 g (9 with moderate or severe BPD (=BPD), 13 without BPD (=No-BPD)) and 15 healthy term-born children (=CONTROL) were included in the study. Physical activity was measured by accelerometry, lung function by spirometry and exercise capacity by an incremental cardiopulmonary exercise test. RESULTS: Peak oxygen uptake was reduced in the BPD-group (83 ± 11%predicted) compared to the No-BPD group (91 ± 8%predicted) and the CONTROL group (94 ± 9%predicted). In a general linear model, variance of peak oxygen uptake was significantly explained by BPD status and height but not by prematurity (p < 0.001). Compared to CONTROL, all children born preterm spent significantly more time in sedentary behaviour (BPD 478 ± 50 min, No-BPD 450 ± 52 min, CONTROL 398 ± 56 min, p < 0.05) and less time in moderate-to-vigorous-physical activity (BPD 13 ± 8 min, No-BPD 16 ± 8 min, CONTROL 33 ± 16 min, p < 0.001). Prematurity but not BPD contributed significantly to explained variance in a general linear model of sedentary behaviour and likewise moderate-to-vigorous-physical activity (p < 0.05 and p < 0.001 respectively). CONCLUSION: In our cohort, BPD but not prematurity was associated with a reduced exercise capacity at school-age. However, prematurity regardless of BPD was related to less engagement in physical activity and more time spent in sedentary behaviour. Thus, our findings suggest diverging effects of prematurity and BPD on exercise capacity and physical activity.

Size-adjusted muscle power and muscle metabolism in patients with cystic fibrosis are equal to healthy controls - a case control study.

BACKGROUND: Skeletal muscle function dysfunction has been reported in patients with cystic fibrosis (CF). Studies so far showed inconclusive data whether reduced exercise capacity is related to intrinsic muscle dysfunction in CF. METHODS: Twenty patients with CF and 23 age-matched controls completed an incremental cardiopulmonary cycling test. Further, a Wingate anaerobic test to assess muscle power was performed. In addition, all participants completed an incremental knee-extension test with 31P magnetic resonance spectroscopy to assess muscle metabolism (inorganic phosphate (Pi) and phosphocreatinine (PCr) as well as intracellular pH). In the MRI, muscle cross-sectional area of the M. quadriceps (qCSA) was also measured. A subgroup of 15 participants (5 CF, 10 control) additionally completed a continuous high-intensity, high-frequency knee-extension exercise task during 31P magnetic resonance spectroscopy to assess muscle metabolism. RESULTS: Patients with CF showed a reduced exercise capacity in the incremental cardiopulmonary cycling test (VO2peak: CF 77.8 ± 16.2%predicted (36.5 ± 7.4 ml/qCSA/min), control 100.6 ± 18.8%predicted (49.1 ± 11.4 ml/qCSA/min); p < 0.001), and deficits in anaerobic capacity reflected by the Wingate test (peak power: CF 537 ± 180 W, control 727 ± 186 W; mean power: CF 378 ± 127 W, control 486 ± 126 W; power drop CF 12 ± 5 W, control 8 ± 4 W. all: p < 0.001). In the knee-extension task, patients with CF achieved a significantly lower workload (p < 0.05). However, in a linear model analysing maximal work load of the incremental knee-extension task and results of the Wingate test, respectively, only muscle size and height, but not disease status (CF or not) contributed to explaining variance. In line with this finding, no differences were found in muscle metabolism reflected by intracellular pH and the ratio of Pi/PCr at submaximal stages and peak exercise measured through MRI spectroscopy. CONCLUSIONS: The lower absolute muscle power in patients with CF compared to controls is exclusively explained by the reduced muscle size in this study. No evidence was found for an intrinsic skeletal muscle dysfunction due to primary alterations of muscle metabolism.

Is sweat testing for cystic fibrosis feasible in patients with down syndrome?

BACKGROUND: Recurrent airway infections are common in patients with Down's syndrome (DS). Hence, ruling out Cystic Fibrosis (CF) in these patients is often required. In the past, the value of sweat testing - the gold standard to diagnose CF - has been questioned in DS as false positive results have been reported. However, these reports are based on measurements of sweat osmolality or sodium concentrations, not chloride concentrations. This study analyses sweat secretion rate and chloride concentration in sweat samples of patients with DS in comparison to healthy controls. METHODS: We assessed sweat samples in 16 patients with DS and 16 healthy controls regarding sweat secretion rate (SSR) and sweat chloride concentration. RESULTS: All measured chloride concentrations were within the normal range. The chloride concentrations were slightly, but not significantly lower in patients with DS (15,54 mmol/l (±4,47)) compared to healthy controls (18,31 mmol/l (±10,12)). While no gender gap in chloride concentration could be found, chloride concentration increased with age in both groups. Insufficient sweat was collected in 2 females with DS (12.5% of the study group) but not in an individual of the control group. A significant lower sweat secretion rate was found in the DS group (27,6 µl/30 min (± 12,18)) compared to the control group (42,7 µl/30 min (± 21,22)). In a sub-analysis, female patients produced significantly less sweat (20,8 ± 10,6 µl/30 min) than male patients with DS (36,4 ± 7,8 µl/30 min), which accounts for the difference between patients and controls. Furthermore, while the sweating secretion rate increased with age in the control group, it did not do so in the DS group. Once again this was due to female patients with DS, who did not show a significant increase of sweat secretion rate with age. CONCLUSIONS: Sweat chloride concentrations were within the normal range in patients with DS and therefore seem to be a reliable tool for testing for CF in these patients. Interestingly, we found a reduced sweat secretion rate in the DS group. Whether the last one has a functional and clinical counterpart, possibly due to a disturbed thermoregulation in DS patients, requires further investigation.

Validation of activity questionnaires in patients with cystic fibrosis by accelerometry and cycle ergometry.

BACKGROUND: The objective of this study was to validate physical activity questionnaires for cystic fibrosis (CF) against accelerometry and cycle ergometry. METHODS: 41 patients with CF (12-42 years) completed the Habitual Activity Estimation Scale (HAES), the 7-Day Physical Activity Recall questionnaire (7D-PAR) and the Lipid Research Clinics questionnaire (LRC) and performed an incremental exercise test according to the Godfrey protocol up to volitional fatigue. Time spent in moderate and vigorous physical activity (MVPA) assessed objectively by accelerometry was related to the time spent in the respective activity categories by correlation analyses and calculating intraclass correlation coefficients (ICC). Furthermore, the results of the exercise test were correlated with the results of the questionnaires. RESULTS: Time spent in the categories 'hard','very hard' and 'hard & very hard' of the 7D-PAR (0.41 < r < 0.56) and 'active' (r = 0.33) of the HAES correlated significantly with MVPA. The activity levels of the LRC were not related to objectively determined physical activity. Significant ICCs were only observed between the 7D-PAR activitiy categories and MVPA (ICC = 0.40-0.44). Only the LRC showed moderate correlations with the exercise test (Wmax: r = 0.46, p = 0.002; VO2peak: r = 0.32, p = 0.041). CONCLUSIONS: In conclusion, the activity categories 'hard' and 'very hard' of the 7D-PAR best reflected objectively measured MVPA. Since the association was at most moderate, the 7D-PAR may be selected to describe physical activity within a population. None of the evaluated questionnaires was able to generate valid physical activity data exercise performance data at the individual level. Neither did any of the questionnaires provide a valid assessment of aerobic fitness on an invidual level.

Does allogeneic stem cell transplantation in survivors of pediatric leukemia impact regular physical activity, pulmonary function, and exercise capacity?

BACKGROUND: Allogeneic hematopoietic stem cell transplantation (allo-HSCT) has improved survival in high-risk childhood leukemia but is associated with long-term sequelae such as impaired pulmonary function and reduced exercise capacity impacting quality of life. METHODS: A convenience sample of 17 patients after allo-HSCT (HSCT-12 male, age 15.7±6.7 years, time after HSCT 5.3±2.8 years) underwent pulmonary function testing, echocardiography, and an incremental exercise test on a bike. Physical activity and health-related quality of life were assessed by questionnaires (7-day physical activity recall, PEDS-QL). Seventeen healthy age- and gender-matched controls served as control group (CG) for results of pulmonary function and exercise testing. RESULTS: HSCT showed reduced pulmonary function (HSCT vs. CG: FEV1 90.5±14.0 vs. 108.0±8.7%pred; FVC 88.4±19.3 vs. 107.6±6.9%pred, DLCO 75.3±23.6 vs. 104.9±12.8%pred) and exercise capacity (VO2peak 89±30.8%pred, CG 98±17.5%pred; Wmax 84±21.7%pred, CG 115±22.8%pred), but no relevant cardiac dysfunction and a good quality of life (PEDS-QL mean overall score 83.3±10.7). Differences in peak oxygen uptake between groups were mostly explained by 5 adolescent patients who underwent total body irradiation for conditioning. They showed significantly reduced diffusion capacity and reduced peak oxygen uptake. Patients reported a mean time of inactivity of 777±159min/day, moderate activity of 110±107 min/day, hard activity of 35±36 min/day, and very hard activity of 23±22 min/day. A higher amount of inactivity was associated with a lower peak oxygen uptake (correlation coefficient tau -0.48, p=0.023). CONCLUSIONS: This pilot study shows that although patients after allo-HSCT reported a good quality of life, regular physical activity and exercise capacity are reduced in survivors of stem cell transplantation, especially in adolescents who are treated with total body irradiation for conditioning. Factors hindering regular physical activity need to be identified and exercise counseling should be part of follow-up visits in these patients.

Prevention through Activity in Kindergarten Trial (PAKT): a cluster randomised controlled trial to assess the effects of an activity intervention in preschool children.

BACKGROUND: Physical activity and motor skills acquisition are of high importance for health-related prevention and a normal development in childhood. However, few intervention studies exist in preschool children focussing on an increase in physical activity and motor skills. Proof of positive effects is available but not consistent. METHODS/DESIGN: The design, curriculum, and evaluation strategy of a cluster randomised intervention study in preschool children are described in this manuscript. In the Prevention through Activity in Kindergarten Trial (PAKT), 41 of 131 kindergartens of Wuerzburg and Kitzingen, Germany, were randomised into an intervention and a control group by a random number table stratified for the location of the kindergarten in an urban (more than 20,000 inhabitants) or rural area. The aims of the intervention were to increase physical activity and motor skills in the participating children, and to reduce health risk factors as well as media use. The intervention was designed to involve children, parents and teachers, and lasted one academic year. It contained daily 30-min sessions of physical education in kindergarten based on a holistic pedagogic approach termed the "early psychomotor education". The sessions were instructed by kindergarten teachers under regular supervision by the research team. Parents were actively involved by physical activity homework cards. The kindergarten teachers were trained in workshops and during the supervision. Assessments were performed at baseline, 3-5 months into the intervention, at the end of the intervention and 2-4 months after the intervention. The primary outcomes of the study are increases in physical activity (accelerometry) and in motor skills performance (composite score of obstacle course, standing long jump, balancing on one foot, jumping sidewise to and fro) between baseline and the two assessments during the intervention. Secondary outcomes include decreases in body adiposity (BMI, skin folds), media use (questionnaire), blood pressure, number of accidents and infections (questionnaire), increases in specific motor skills (throwing, balancing, complex motor performance, jumping) and in flexibility. DISCUSSION: If this trial proofs the effectiveness of the multilevel kindergarten based physical activity intervention on preschooler's activity levels and motor skills, the programme will be distributed nationwide in Germany. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT00623844.

Correction to: Physical activity and health-related quality of life in chronic non-bacterial osteomyelitis.

Following publication of the original article [1], we have been notified that the authors' first names and last names are presented in wrong order. The presentation of names, thus, should be as follows.

Differential modulation of pulmonary caspases: Is this the key to Ureaplasma-driven chronic inflammation?

Although accepted agents in chorioamnionitis and preterm birth, the role of Ureaplasma species (spp.) in inflammation-driven morbidities of prematurity, including the development of bronchopulmonary dysplasia, remains controversial. To add to scarce in vitro data addressing the pro-inflammatory capacity of Ureaplasma spp., pulmonary epithelial-like A549 cells and human pulmonary microvascular endothelial cells (HPMEC) were incubated with Ureaplasma (U.) urealyticum, U. parvum, and Escherichia coli lipopolysaccharide (LPS). Ureaplasma isolates down-regulated caspase mRNA levels in A549 cells (caspase 8: p<0.001, 9: p<0.001, vs. broth), while increasing caspase protein expression, enzyme activity, and cell death in HPMEC (active caspase 3: p<0.05, caspase 8: p<0.05, active caspase 9: p<0.05, viability: p<0.05). LPS, contrarily, induced caspase mRNA expression in HPMEC (caspase 3: p<0.01, 4: p<0.001, 5: p<0.001, 8: p<0.001, vs. control), but not in A549 cells, and did not affect enzyme activity or protein levels in either cell line. LPS, but neither Ureaplasma isolate, enhanced mRNA expression of pro-inflammatory interleukin (IL)-6 in both A549 (p<0.05, vs. control) and HPMEC (p<0.001) as well as tumor necrosis factor-α (p<0.01), IL-1ß (p<0.001), and IL-8 (p<0.05) in HPMEC. We are therefore the first to demonstrate a differential modulation of pulmonary caspases by Ureaplasma spp. in vitro. Ureaplasma-driven enhanced protein expression and activity of caspases in pulmonary endothelial cells result in cell death and may cause structural damage. Down-regulated caspase mRNA in pulmonary epithelial cells, contrarily, may indicate Ureaplasma-induced inhibition of apoptosis and prevent effective immune responses. Both may ultimately contribute to chronic Ureaplasma colonization and long-term pulmonary inflammation.

Successful treatment of severe arterial hypotension and anuria in a preterm infant with renal tubular dysgenesis- a case report.

BACKGROUND: Oligohydramnios sequence can be caused by renal tubular dysgenesis (RTD), a rare condition resulting in pulmonary and renal morbidity. Besides typical features of Potter-sequence, the infants present with severe arterial hypotension and anuria as main symptoms. Establishing an adequate arterial blood pressure and sufficient renal perfusion is crucial for the survival of these infants. CASE PRESENTATION: We describe a male preterm infant of 34 + 0 weeks of gestation. Prenatally oligohydramnios of unknown cause was detected. After uneventful delivery and good adaptation the infant developed respiratory distress due to a spontaneous right-sided pneumothorax and required thoracocentesis and placement of a chest tube; he showed no major respiratory concerns thereafter and needed only minimal ventilatory support. Echocardiography revealed no abnormalities, especially no pulmonary hypertension. However, he suffered from severe arterial hypotension and anuria refractory to catecholamine therapy (dobutamine, epinephrine and noradrenaline). After 36 h of life, vasopressin therapy was initiated resulting in an almost immediate stabilization of arterial blood pressure and subsequent onset of diuresis. Therapy with vasopressin was necessary for three weeks to maintain adequate arterial blood pressure levels and diuresis. Sepsis and adrenal insufficiency were ruled out as inflammation markers, microbiological tests and cortisol level were normal. At two weeks of age, our patient developed electrolyte disturbances which were successfully treated with fludrocortisone. He did not need renal replacement therapy. Genetic analyses revealed a novel compound hyterozygous mutation of RTD. Now 17 months of age, the patient is in clinically stable condition with treatment of fludrocortisone and sodium bicarbonate. He suffers from stage 2 chronic kidney disease; blood pressure, motor and cognitive development are normal. CONCLUSIONS: RTD is a rare cause of oligohydramnios sequence. Next to pulmonary hypoplasia, severe arterial hypotension is responsible for poor survival. We present the only second surviving infant with RTD, who did not require renal replacement therapy during the neonatal period. It can be speculated whether the use of vasopressin prevents renal replacement therapy as vasopressin increases urinary output by improving renal blood flow.

Representation of cerebral bridging veins in infants by postmortem computed tomography.

The postmortem diagnosis of shaken baby syndrome, a severe form of child abuse, may be difficult, especially when no other visible signs of significant trauma are obvious. An important finding in shaken baby syndrome is subdural haemorrhage, typically originating from ruptured cerebral bridging veins. Since these are difficult to detect at autopsy, we have developed a special postmortem computed tomographic (PMCT) method to demonstrate the intracranial vein system in infants. This method is minimally invasive and can be carried out conveniently and quickly on clinical computed tomography (CT) systems. Firstly, a precontrast CT is made of the infant's head, to document the original state. Secondly, contrast fluid is injected manually via fontanel puncture into the superior sagittal sinus, followed by a repeat CT scan. This allows the depiction of even very small vessels of the deep and superficial cerebral veins, especially the bridging veins, without damaging them. Ruptures appear as extravasation of contrast medium, which helps to locate them at autopsy and examine them histologically, whenever necessary.

Sera of patients with recurrent miscarriages containing anti-trophoblast antibodies (ATAB) reduce hCG and progesterone production in trophoblast cells in vitro.

PROBLEM: Reproductive failure including RM has been suggested to correlate with antibodies that cross react with HLA-negative syncytiotrophoblasts and we have reported that 17% of women with 2 or more miscarriages and 34% of women with 3 or more miscarriages express anti-trophoblast antibodies (ATAB). Until now, the mechanism, how ATAB interfere with pregnancy success is not known. HCG and progesterone both play fundamental roles in supporting human pregnancy. Therefore we investigated the effects of sera of RM patients containing ATAB on the hCG and progesterone production of cells of the choriocarcinoma cell line JEG-3. METHOD OF STUDY: In vitro study to investigate effects of patient sera with and without ATAB on hCG and progesterone secretion of JEG-3 cells. The presence of ATAB was detected as described earlier. Effects of sera from ATAB positive and ATAB negative RM patients on hCG and progesterone secretion by JEG-3 cells were analysed 12 and 24h after plating. Sera of women without pregnancy pathologies served as controls. RESULTS: Sera of ATAB-positive RM patients significantly inhibit hCG secretion of JEG-3 cells for 12h after plating compared to sera of healthy controls (p=0.019) and significantly reduce progesterone production for 12h (p=0.046) and 24h (p=0.027) of co-culture. Sera of ATAB-negative RM patient show no significant effect on progesterone secretion. CONCLUSIONS: Inhibition of hCG and progesterone production might point to a mechanism, how ATAB interfere with early pregnancies.

Perspective on cystic fibrosis and physical activity: Is there a difference compared to healthy individuals?

OBJECTIVES: The aim of this study was to compare habitual physical activity between cystic fibrosis (CF) patients and healthy controls and to investigate possible predictors for reduced physical activity in CF patients. METHODS: Sixty-six patients with CF (3-44 years) and 65 healthy controls (3-55 years) were asked to wear an accelerometer (Actigraph GT1M) for 9 days (at least 10 hr/day). Physical activity was classified in five categories from very low to very strenuous. RESULTS: In general, there was no difference in physical activity between CF patients and healthy controls. However, young school-aged 6-13 years old children with CF spent less time with strenuous and very strenuous activity than healthy controls (adjusted difference in activity -0.43 (-0.69, -0.17)). Patients with very low lung function were significantly less active, but other CF-associated conditions did not affect physical activity. CONCLUSIONS: While we found similar levels of physical activity measured by accelerometry in patients with CF compared to healthy controls in general, young school-aged children showed less engagement in strenuous activities than their healthy counterparts. As the reduced physical activity in young school children was not likely to be explained by the disease state, strenuous physical activity may be enhanced by advocating exercise and sport. Pediatr Pulmonol. 2016;51:1020-1030. © 2016 Wiley Periodicals, Inc.

[Visualization of bridging veins by means of postmortem computed tomography]. / Darstellung der Brückenvenen mit der postmortalen Computertomographie.

At autopsy, visualization of lesions of the bridging veins, a frequent source of subdural bleeding, is difficult due to their anatomical localization. On the other hand their demonstration is of great importance for the assignment to a chronologically defined trauma. For this reason a postmortem method using computed tomography was developed to visualize the intracranial venous system by means of X-ray contrast media. In subdural bleedings, in which the skull had not been opened up, ruptured vessels could be accurately localized with this method, so that targeted dissection was possible during the subsequent autopsy.

Effects of a Physical Activity Intervention in Preschool Children.

PURPOSE: This study aimed to evaluate a multicomponent, child-appropriate preschool intervention program led by preschool teachers to enhance physical activity (PA) and motor skill performance (MS) in 4- and 5-yr-old children. METHODS: Evaluation involved 709 children (mean age, 4.7 ± 0.6 yr; 49.5% girls) from 41 preschools (intervention group, n = 21; control group, n = 20) in the rural and urban surroundings of two German cities. Children in the intervention group received a daily PA intervention lasting 30 min and PA homework over one academic year, which was designed by professionals but led by preschool teachers. The intervention included educational components for parents and teachers. Primary outcomes were MS (composite MS score) and objectively measured moderate-to-vigorous PA (MVPA) by accelerometry. Measurements were performed at baseline, midintervention, and postintervention as well as 2-4 months after the end of intervention. Intervention effects were analyzed by repeated measurement analysis adjusted for group, sex, age, baseline outcomes, urban/rural location of the preschool, and cluster (preschool). RESULTS: Compared with controls, children in the intervention group showed positive effects in MS at postintervention (estimate effect, 0.625 z-score points; 95% confidence interval (CI), 0.276-0.975; P = 0.001) and at follow-up (estimate effect, 0.590 z-score points; 95% CI, 0.109-1.011; P = 0.007) and an increase in MVPA from baseline to postintervention by 0.5% of total wearing time (95% CI, 0.002%-1.01%; P = 0.049) at borderline significance. There was no benefit on MVPA for the intervention group between baseline and follow-up. CONCLUSIONS: A child-appropriate, multidimensional PA intervention could sustainably improve MS but not PA. Findings suggest that a change in health-related behaviors is difficult. Future research should implement participatory intervention components in preschool setting and better integrate the families of the children.

Acute Muscle Trauma due to Overexercise in an Otherwise Healthy Patient with Cystic Fibrosis.

Cystic fibrosis (CF) is one of the most common inherited diseases and is caused by mutations in the CFTR gene. Although the pulmonary and gastrointestinal manifestations of the disease remain in the focus of treatment, recent studies have shown expression of the CFTR gene product in skeletal muscle cells and observed altered intramuscular Ca(2+) release dynamics in CFTR-deficient animal models. Physical exercise is beneficial for maintaining fitness and well-being in CF patients and constitutes one aspect of modern multimodal treatment, which has considerably increased life span and reduced morbidity. We report on a case of acute muscle trauma resulting from excessive dumbbell exercise in a young adult with cystic fibrosis and describe clinical, laboratory and imaging characteristics of acute exercise-induced muscle injury.

Risks associated with exercise testing and sports participation in cystic fibrosis.

BACKGROUND: Severe adverse reactions (SARs) associated with physical exercise have not been systematically studied in cystic fibrosis (CF). METHODS: Two surveys were conducted to assess the incidence of exercise-related SARs: a caregiver survey asking for complications associated with exercise testing and in-hospital training therapy and a web-based patient survey asking for problems with exercise. RESULTS: 78 of 107 CF facilities caring for 4208 patients responded to the caregiver survey, 256 patients answered the web-based survey. No SARs were reported for 713 exercise tests. With in-hospital training, the yearly incidence of exercise-related SARs such as pneumothorax, cardiac arrhythmia, injury or hypoglycaemia was <1% each, the respective lifetime incidences reported by the patients were 0.8-6.3%. 67% of the patients reported no SARs with exercise. CONCLUSIONS: Exercise testing is safe in patients with CF. Despite the limitations in quality of data, the incidence of exercise-related SARs appears low in this population.

Exercise-induced hypoxemia and cardiac arrhythmia in cystic fibrosis.

BACKGROUND: Physical activity has become part of the therapy of patients with cystic fibrosis (CF) despite possible risks. The objectives of this study were to identify predictors of hypoxemia and to search for cardiac arrhythmia during exercise. METHODS: The data of 75 patients (12 to 41 years old) with CF who underwent a standardized incremental exercise test on a cycle ergometer was analyzed. Oxygen saturation (SpO(2)) and ECG were monitored. The results were related to spirometric and SpO(2) measurements at rest. RESULTS: During exercise, 17 patients suffered from significant desaturations (SpO(2)<90%). SpO(2) at peak exercise was independently related to SpO(2) at rest and 1/FEV1 (multiple regression R(2)=0.63). Five patients demonstrated ventricular arrhythmias during exercise. No unambiguous prediction of exercise-induced hypoxemia or cardiac arrhythmia was possible. CONCLUSION: In order to detect all patients with exercise-induced hypoxemia and cardiac arrhythmia, an incremental exercise test to volitional fatigue must be performed.