Speckle tracking echocardiography in chronic obstructive pulmonary disease and overlapping obstructive sleep apnea.

BACKGROUND: COPD and congestive heart failure represent two disease entities of growing global burden that share common etiological features. Therefore, we aimed to identify the degree of left ventricular (LV) dysfunction in COPD as a function of COPD severity stages and concurrently placed particular emphasis on the presence of overlapping obstructive sleep apnea (OSA). METHODS: A total of 85 COPD outpatients (64.1±10.4 years, 54.1% males) and 20 controls, matched for age, sex, and smoking habits, underwent speckle tracking echocardiography for LV longitudinal strain imaging. Complementary 12-lead electrocardiography, laboratory testing, and overnight screening for sleep-disordered breathing using the SOMNOcheck micro(®) device were performed. RESULTS: Contrary to conventional echocardiographic parameters, speckle tracking echocardiography revealed significant impairment in global LV strain among COPD patients compared to control smokers (-13.3%±5.4% vs -17.1%±1.8%, P=0.04). On a regional level, the apical septal LV strain was reduced in COPD (P=0.003) and associated with the degree of COPD severity (P=0.02). With regard to electrocardiographic findings, COPD patients exhibited a significantly higher mean heart rate than controls (71.4±13.0 beats per minute vs 60.3±7.7 beats per minute, P=0.001) that additionally increased over Global Initiative for Chronic Obstructive Lung Disease stages (P=0.01). Albeit not statistically significant, COPD led to elevated N-terminal pro-brain natriuretic peptide levels (453.2±909.0 pg/mL vs 96.8±70.0 pg/mL, P=0.08). As to somnological testing, the portion of COPD patients exhibiting overlapping OSA accounted for 5.9% and did not significantly vary either in comparison to controls (P=0.07) or throughout the COPD Global Initiative for Chronic Obstructive Lung Disease stages (P=0.49). COPD-OSA overlap solely correlated with nocturnal hypoxemic events, whereas LV performance status was unrelated to coexisting OSA. CONCLUSION: To conclude, COPD itself seems to be accompanied with decreased LV deformation properties that worsen over COPD severity stages, but do not vary in case of overlapping OSA.

Lower extremity and carotid artery disease in COPD.

In view of their common chronic inflammatory process, we sought to determine the linkage between peripheral artery disease and chronic obstructive pulmonary disease (COPD). 107 COPD patients (mean±sd age 64.6±10.4 years, 52.2% male) and 22 control smokers without previously diagnosed peripheral artery disease underwent standardised angiological examination for lower extremity artery disease (LEAD) and carotid artery disease. LEAD was significantly more prevalent in COPD patients than in controls (80.4% versus 54.5%, p=0.002). Among COPD patients, 57.0%, 12.2%, 10.3% and 0.9% were found to be in Fontaine stages I, IIA, IIB and III, respectively. As with carotid artery disease, its frequency increased from 36.4% in controls to 58.9% in COPD patients (p=0.003). Carotid plaque burden, LEAD Fontaine degrees as well as pulse wave index and ankle-brachial index manifested significant impairment over percentage predicted forced expiratory volume in 1 s (FEV1 % pred) (p=0.02, p<0.001, p=0.01 and p<0.001, respectively). Multivariate analysis revealed that COPD Global Initiative for Chronic Obstructive Lung Disease status was the strongest independent predictor for the presence of plaque in lower extremity arteries (odds ratio 1.63, 95% CI 1.19-2.25, p=0.003) and carotids (odds ratio 1.66, 95% CI 1.14-2.44, p=0.009). As compared with control smokers, peripheral artery disease is diagnosed in a sizeable proportion of COPD patients and exhibits significant distributive differences over FEV1 % pred that exceed the susceptibility conferred by common cardiovascular stressors.