Incidental coronary artery calcifications found in low-dose computed tomography screening for lung cancer are an independent predictor of long-term mortality

RESEARCH LETTER Coronary artery calcifications on LDCT as predictors of long -term mortality 1 was responsible for the design, organization, and co -ordination of the program.The program ran from February 2009 to April 2011 and included patients at a high risk for developing lung cancer.The inclusion criteria were age of 50-75 years, a history of smoking (at least 1 pack per day for 20 years), and no signs or symptoms of lung cancer.Other risk factors and comorbidities were not considered in the program. 2 LDCT was performed in 1 of the 19 CT laboratories participating in the program.It involved a multi -row CT scanner and the following exposure conditions: 120 kV, 50 mAs, 3 -second scan time, and a radiation dose of approximately 1-1.5 mSv.An ordinal scoring of calcification in the coronary arteries was applied.Four sections of the coronary arteries were identified on LDCT images: left main coronary artery, left anterior descending coronary artery, left circumflex artery, and right coronary artery.Each of the listed arteries was assigned a calcification severity category expressed as a number: 0 meant no calcification, 1 was slight calcification (less than one -third of the vessel length), 2 denoted moderate calcification (more than one -third but less than two -thirds of the vessel length), and 3 meant heavy calcification (more than two -thirds of the vessel length).Based on the ordinal analysis of the calcifications, the degree of CAC was expressed with the Coronary Artery Calcification score (CACs) ranging from 0 to 12 points.Four categories were defined after the initial analysis, encompassing 0, 1-3, 4-6, and 7-12 points, which were further investigated.