SESSION TYPE: COPD: Severity and Risk Predictors
PRESENTED ON: Monday, October 22, 2012 at 11:15 AM - 12:30 PM
PURPOSE: To assess the relationship between the total cross-sectional area (CSA) of small pulmonary vessels on computed tomography (CT) images and both coronary arterial calcification index and extent of significant stenotic coronary segments in COPD patients
METHODS: Study group consisted of 46 COPD patients and 25 emphysema patients without airflow limitation who underwent both coronary CT angiography (CTA) and low-dose chest CT by 320-row scanner. On segment-basis, presence of significant coronary stenosis with greater than 75% was determined by curved planner reformatted images of CTA. Coronary calcification quantified by Agatston score was measured in dedicated workstation. In addition to FEV1/FVC% as an index of airflow limitation measured by pulmonary functional test, the percentage of total CSA of less than 5 mm2 for the total lung area (%CSA<5) in the three selected slices in the upper, middle and lower lung field as an index of pulmonary vascular alteration and ratio of low attenuation area in the same slices defined as ratio of pixel under -950 HU as index of emphysema (LAAR) were calculated by using Image J. Coefficients of correlation between %CSA<5 and COPD index (FEV1/FVC% or LAAR) were obtained. Both %CSA<5 and COPD indices were correlated with the Agatston scores and extent of stenotic coronary segments.
RESULTS: %CSA<5 had moderate positive correlation with FEV1/FVC% (r=0.351, p=0.003), and negative correlation with LAAR (r=-0.421, p<0.001). Although Agatston score correlated with extent of stenotic coronary segments (r=0.579, p<0.001), any of 3 indices did not have meaningful correlation with extent of stenotic coronary segments. %CSA<5 had moderate negative correlation with Agatston score (r=-0.490, p<0.001) while neither FEV1/FVC% nor LAAR correlated with Agatston score (r=-0.139, p=0.248 and r= -0.074, p=0.537, respectively).
CONCLUSIONS: %CSA<5 decreased in accordance with increased coronary calcification index despite no association with extent of segment-based coronary stenosis, implying that pulmonary vascular alteration is related to coronary atherosclerotic burden.
CLINICAL IMPLICATIONS: Pulmonary vascular alteration can be important index of COPD with association with prognosis of ischemic heart disease.
DISCLOSURE: The following authors have nothing to disclose: Yukihiro Nagatani, Masashi Takahashi, Hiroshi Sakai, Norihisa Nitta, Hiromitsu Noda, Yasutaka Nakano, Hideji Otani, Akinaga Sonoda, Kiyoshi Murata
No Product/Research Disclosure InformationShiga University of Medical Science, Otsu, Japan