Augmentation Index in Patients with Thoracic Aortic Aneurysm: A Matched Case-Control Study

Thoracic aortic aneurysms (TAA) may be associated with complications such as rupture and dissection, which can lead to a fatal outcome. Increased central arterial stiffness has been proposed to be present in patients with TAA compared to unmatched controls. We aimed to assess whether wall properties in patients with TAA are also altered when compared to a matched control group. Applanation tonometry was performed in 74 adults with TAA and 74 sex, age, weight, height, and left ventricular ejection fraction matched controls. Subsequently analysis of the pulse wave was done using the SphygmoCor System. For comparing the two groups, AIx was adjusted to a heart rate of 75/min (AIx@75). 148 1-to-1 matched participants were included in the final model. There was no significant difference in the Alx@75 between the TAA group and the matched control group [mean (SD) of 24.7 (11.2) % and 22.8 (11.2) %, p = 0.240]. Adjusted for known cardiovascular risk factors, there was no association between TAA and AIx@75. Patients with TAA showed comparable arterial wall properties to cardiovascular risk factor matched controls. Since higher arterial stiffness is associated with TAA progression, it remains to be investigated if increased central arterial stiffness is a relevant factor of TAA emergence. Keywords: thoracic aortic aneurysm; augmentation index; arterial stiffnes

Dimensions of Consistency in GSD: Social Factors, Structures and Interactions

Peer reviewe

Effect of simulated obstructive hypopnea and apnea on thoracic aortic wall transmural pressures.

Preliminary evidence supports an association between obstructive sleep apnea (OSA) and thoracic aortic dilatation, although potential causative mechanisms are incompletely understood; these may include an increase in aortic wall transmural pressures, induced by obstructive apneas and hypopneas. In patients undergoing cardiac catheterization, mean blood pressure (MBP) in the thoracic aorta and esophageal pressure was simultaneously recorded by an indwelling aortic pigtail catheter and a balloon-tipped esophageal catheter in randomized order during: normal breathing, simulated obstructive hypopnea (inspiration through a threshold load), simulated obstructive apnea (Mueller maneuver), and end-expiratory central apnea. Aortic transmural pressure (aortic MBP minus esophageal pressure) was calculated. Ten patients with a median age (range) of 64 (46-75) yr were studied. Inspiration through a threshold load, Mueller maneuver, and end-expiratory central apnea was successfully performed and recorded in 10, 7, and 9 patients, respectively. The difference between aortic MBP and esophageal pressure (and thus the extra aortic dilatory force) was median (quartiles) +9.3 (5.4, 18.6) mmHg, P = 0.02 during inspiration through a threshold load, +16.3 (12.8, 19.4) mmHg, P = 0.02 during the Mueller maneuver, and +0.4 (-4.5, 4.8) mmHg, P = 0.80 during end-expiratory central apnea. Simulated obstructive apnea and hypopnea increase aortic wall dilatory transmural pressures because intra-aortic pressures fall less than esophageal pressures. Thus OSA may mechanically promote thoracic aortic dilatation and should be further investigated as a risk factor for the development or accelerated progression of thoracic aortic aneurysms

Effect of simulated obstructive hypopnea and apnea on thoracic aortic wall transmural pressures.

Preliminary evidence supports an association between obstructive sleep apnea (OSA) and thoracic aortic dilatation, although potential causative mechanisms are incompletely understood; these may include an increase in aortic wall transmural pressures, induced by obstructive apneas and hypopneas. In patients undergoing cardiac catheterization, mean blood pressure (MBP) in the thoracic aorta and esophageal pressure was simultaneously recorded by an indwelling aortic pigtail catheter and a balloon-tipped esophageal catheter in randomized order during: normal breathing, simulated obstructive hypopnea (inspiration through a threshold load), simulated obstructive apnea (Mueller maneuver), and end-expiratory central apnea. Aortic transmural pressure (aortic MBP minus esophageal pressure) was calculated. Ten patients with a median age (range) of 64 (46-75) yr were studied. Inspiration through a threshold load, Mueller maneuver, and end-expiratory central apnea was successfully performed and recorded in 10, 7, and 9 patients, respectively. The difference between aortic MBP and esophageal pressure (and thus the extra aortic dilatory force) was median (quartiles) +9.3 (5.4, 18.6) mmHg, P = 0.02 during inspiration through a threshold load, +16.3 (12.8, 19.4) mmHg, P = 0.02 during the Mueller maneuver, and +0.4 (-4.5, 4.8) mmHg, P = 0.80 during end-expiratory central apnea. Simulated obstructive apnea and hypopnea increase aortic wall dilatory transmural pressures because intra-aortic pressures fall less than esophageal pressures. Thus OSA may mechanically promote thoracic aortic dilatation and should be further investigated as a risk factor for the development or accelerated progression of thoracic aortic aneurysms

Periostin levels do not distinguish chronic obstructive pulmonary disease patients with frequent and infrequent exacerbations

Background: Periostin, an extracellular matrix protein, is involved in inflammatory processes of the lung. To date, most studies have focused on periostin in asthma patients, its role in chronic obstructive pulmonary disease (COPD) is less clear and no information has been reported on blood levels of periostin in COPD patients in the context of exacerbation rates. As such, this exploratory study aimed to investigate whether periostin is helpful to distinguish between COPD patients with frequent and infrequent exacerbations. Methods: We performed an examination of patients with COPD participating in a COPD cohort study in Switzerland. Periostin levels were determined in serum samples by using a commercially available enzyme-linked immunosorbent assay (ELISA) kit. Patients underwent evaluation of clinical symptoms including exacerbation rate (exacerbation defined by requiring oral corticosteroids and/or antibiotics) and lung function. In a subgroup of patients an annual follow-up was available that was considered in an additional analysis. Results: Twenty six patients (global initiative of obstructive lung disease (GOLD) stage 1 none, 31% stage 2, 38% stage 3, 31% stage 4) were included in the analysis. The mean±standard deviation (SD) age of the patients was 63±5.9 years, 16 were males, 24 were smokers or exsmokers. The median (quartiles) post-bronchodilator FEV1% predicted was 36(27/57). There was no significant difference in periostin levels between patients with frequent and infrequent exacerbations. The follow-up data revealed no evidence that periostin is helpful in distinguishing frequent from infrequent exacerbators. Conclusion: Our analysis performed in a small group of carefully matched COPD patients demonstrates that there is no significant relationship between exacerbation rate and periostin levels in blood

Physical activity and the frequency of acute exacerbations in patients with chronic obstructive pulmonary disease

PURPOSE: Acute exacerbations (AE) in patients with COPD are associated with a decline in lung function, increased risk of hospitalization, and mortality. In this cross-sectional study we tested whether the level of objectively measured daily physical activity and exercise capacity are associated with the number of COPD exacerbations. METHODS: In 210 patients with COPD (67 % men; mean (SD) age: 63 (8) years) enrolled in The Obstructive Pulmonary Disease Outcomes Cohort of Switzerland (TOPDOCS) physical activity (PA) (steps per day, physical activity level, (PAL)), exercise capacity (6-min walking distance, (6MWD)), comorbidities, lung function, and medication were assessed. Differences between COPD patients with frequent (≥2 year) and infrequent (0-1 year) exacerbations were assessed. Univariate and multivariate analyses were performed to investigate whether the level of objectively measured daily physical activity and exercise capacity are associated with the number of COPD exacerbations. RESULTS: Patients with frequent AE had a significantly lower FEV1 and 6MWD compared to patients with infrequent AE. In univariate analysis, the number of exacerbations was inversely associated with FEV1, 6MWD, BMI, and smoking status while there was a positive association with RV/TLC and combined inhaled medication. However, there was no significant association with PAL and steps per day. In multivariate analysis, FEV1 and the use of combined inhaled medication were independently associated with the number of AE, after correction for covariates. CONCLUSIONS: The findings of this study imply that FEV1, independent of inhaled medication, is significantly associated with COPD exacerbations. Neither physical activity nor exercise capacity was independently associated with COPD exacerbations

Physical Activity and the Frequency of Acute Exacerbations in Patients with Chronic Obstructive Pulmonary Disease

Purpose: Acute exacerbations (AE) in patients with COPD are associated with a decline in lung function, increased risk of hospitalization, and mortality. In this cross-sectional study we tested whether the level of objectively measured daily physical activity and exercise capacity are associated with the number of COPD exacerbations. Methods: In 210 patients with COPD (67% men; mean (SD) age: 63 (8)years) enrolled in The Obstructive Pulmonary Disease Outcomes Cohort of Switzerland (TOPDOCS) physical activity (PA) (steps per day, physical activity level, (PAL)), exercise capacity (6-min walking distance, (6MWD)), comorbidities, lung function, and medication were assessed. Differences between COPD patients with frequent (≥2year) and infrequent (0-1year) exacerbations were assessed. Univariate and multivariate analyses were performed to investigate whether the level of objectively measured daily physical activity and exercise capacity are associated with the number of COPD exacerbations. Results: Patients with frequent AE had a significantly lower FEV1 and 6MWD compared to patients with infrequent AE. In univariate analysis, the number of exacerbations was inversely associated with FEV1, 6MWD, BMI, and smoking status while there was a positive association with RV/TLC and combined inhaled medication. However, there was no significant association with PAL and steps per day. In multivariate analysis, FEV1 and the use of combined inhaled medication were independently associated with the number of AE, after correction for covariates. Conclusions: The findings of this study imply that FEV1, independent of inhaled medication, is significantly associated with COPD exacerbations. Neither physical activity nor exercise capacity was independently associated with COPD exacerbations