Pulmonary Artery Enlargement Is Associated With Cardiac Injury During Severe Exacerbations of COPD.
Relative pulmonary arterial enlargement, defined by a pulmonary artery to aorta (PA/A) ratio > 1 on CT scanning, predicts hospitalization for acute exacerbations of COPD (AECOPD). However, it is unclear how AECOPD affect the PA/A ratio. We hypothesized that the PA/A ratio would increase at the time of AECOPD and that a ratio > 1 would be associated with worse clinical outcomes.



Patients discharged with an International Classification of Diseases, Ninth Revision, diagnosis of AECOPD from a single center over a 5-year period were identified. Patients were included who had a CT scan performed during the stable period prior to the index AECOPD episode as well as a CT scan at the time of hospitalization. A subset of patients also underwent postexacerbation CT scans. The pulmonary arterial diameter, ascending aortic diameter, and the PA/A ratio were measured on CT scans. Demographic data, comorbidities, troponin level, and hospital outcome data were analyzed.



A total of 134 patients were included in the study. They had a mean age of 65 ± 10 years, 47% were male, and 69% were white; overall, patients had a mean FEV1 of 47% ± 19%. The PA/A ratio increased from baseline at the time of exacerbation (0.97 ± 0.15 from 0.91 ± 0.17; P < .001). Younger age and known pulmonary hypertension were independently associated with an exacerbation PA/A ratio > 1. Patients with PA/A ratio > 1 had higher troponin values. Those with a PA/A ratio > 1 and troponin levels > 0.01 ng/mL had increased acute respiratory failure, ICU admission, or inpatient mortality compared with those without both factors (P = .0028). The PA/A ratio returned to baseline values following AECOPD.



The PA/A ratio increased at the time of severe AECOPD and a ratio > 1 predicted cardiac injury and a more severe hospital course.
Division of Pulmonary, Allergy, and Critical Care, University of Alabama at Birmingham, Birmingham, AL; Department of Medicine, University of Alabama at Birmingham, Birmingham, AL; Lung Health Center, University of Alabama at Birmingham, Birmingham, AL; Birmingham VA Medical Center, Birmingham, AL. Electronic address: jmwells@uab.edu.
J Michael
JM
Wells
Division of Pulmonary, Allergy, and Critical Care, University of Alabama at Birmingham, Birmingham, AL; Department of Medicine, University of Alabama at Birmingham, Birmingham, AL.
Joshua B
JB
Morrison
Division of Pulmonary, Allergy, and Critical Care, University of Alabama at Birmingham, Birmingham, AL; Department of Medicine, University of Alabama at Birmingham, Birmingham, AL; Lung Health Center, University of Alabama at Birmingham, Birmingham, AL.
Surya P
SP
Bhatt
Division of Cardiothoracic Imaging, Department of Radiology, University of Alabama at Birmingham, Birmingham, AL.
Hrudaya
H
Nath
Division of Pulmonary, Allergy, and Critical Care, University of Alabama at Birmingham, Birmingham, AL; Department of Medicine, University of Alabama at Birmingham, Birmingham, AL; Lung Health Center, University of Alabama at Birmingham, Birmingham, AL; Birmingham VA Medical Center, Birmingham, AL.
Mark T
MT
Dransfield
D000367:Age Factors; D000368:Aged; D018450:Disease Progression; D005260:Female; D005541:Forced Expiratory Volume; D006331:Heart Diseases / Q000097:blood* / Q000453:epidemiology; D006801:Humans; D006976:Hypertension, Pulmonary / Q000000981:diagnostic imaging*; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009929:Organ Size; D010102:Oxygen Inhalation Therapy; D011651:Pulmonary Artery / Q000000981:diagnostic imaging* / Q000473:pathology; D029424:Pulmonary Disease, Chronic Obstructive / Q000000981:diagnostic imaging* / Q000453:epidemiology / Q000503:physiopathology / Q000628:therapy; D012189:Retrospective Studies; D012307:Risk Factors; D012720:Severity of Illness Index; D014057:Tomography, X-Ray Computed; D014336:Troponin / Q000097:blood*; D014797:Vital Capacity
D014336:Troponin
COPD; CT scan; acute exacerbation of COPD; enzymes (cardiology); pulmonary circulation