Prospective Study
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World J Radiol. Jun 28, 2014; 6(6): 381-387
Published online Jun 28, 2014. doi: 10.4329/wjr.v6.i6.381
Coronary artery calcium score on low-dose computed tomography for lung cancer screening
Teresa Arcadi, Erica Maffei, Nicola Sverzellati, Cesare Mantini, Andrea I Guaricci, Carlo Tedeschi, Chiara Martini, Ludovico La Grutta, Filippo Cademartiri
Teresa Arcadi, Department of Radiology, SDN Foundation, IRCCS, 80131 Naples, Italy
Erica Maffei, Filippo Cademartiri, Cardio-Vascular Imaging Unit, Department of Radiology, Giovanni XXIII Clinic, Monastier di Treviso, 31050 Treviso, Italy
Erica Maffei, Filippo Cademartiri, Department of Radiology, Erasmus Medical Center University, Rotterdam, 3015 CE Rotterdam, The Netherlands
Nicola Sverzellati, Department of Radiology, Azienda Ospedaliero-Universitaria, 43100 Parma, Italy
Cesare Mantini, Department of Radiology, Università di Chieti, 66100 Chieti, Italy
Andrea I Guaricci, Department of Cardiology, Università di Foggia, 71121 Foggia, Italy
Carlo Tedeschi, Department of Cardiology, San Gennaro Hospital, Naples, 80136 Napoli, Italy
Ludovico La Grutta, Department of Radiology, University of Palermo, Italy
Author contributions: Maffei E, Sverzellati N and Cademartiri F conceived and designed the study; Arcadi T, Mantini C, Guaricci AI, Tedeschi C, Martini C and La Grutta L acquired and analysed data; Arcadi T and Maffei E drafted the manuscript; Sverzellati N, Mantini C, Guaricci AI, Tedeschi C, Martini C, La Grutta L and Cademartiri F revised the manuscript critically for important intellectual content; Arcadi T, Maffei E, Sverzellati N, Mantini C, Guaricci AI, Tedeschi C, Martini C, La Grutta L and Cademartiri F provided final approval for the version to be published.
Correspondence to: Dr. Filippo Cademartiri, MD, PhD, FESC, FSCCT, Professor, Cardio-Vascular Imaging Unit, Department of Radiology, Giovanni XXIII Clinic, Via Giovanni XXIII 7, Monastier di Treviso, 31050 Treviso, Italy.
Telephone: +39-422-896710 Fax: +39-422-896507
Received: December 10, 2013
Revised: February 9, 2014
Accepted: May 8, 2014
Published online: June 28, 2014

AIM: To evaluate the feasibility of coronary artery calcium score (CACS) on low-dose non-gated chest CT (ngCCT).

METHODS: Sixty consecutive individuals (30 males; 73 ± 7 years) scheduled for risk stratification by means of unenhanced ECG-triggered cardiac computed tomography (gCCT) underwent additional unenhanced ngCCT. All CT scans were performed on a 64-slice CT scanner (Somatom Sensation 64 Cardiac, Siemens, Germany). CACS was calculated using conventional methods/scores (Volume, Mass, Agatston) as previously described in literature. The CACS value obtained were compared. The Mayo Clinic classification was used to stratify cardiovascular risk based on Agatston CACS. Differences and correlations between the two methods were compared. A P-value < 0.05 was considered significant.

RESULTS: Mean CACS values were significantly higher for gCCT as compared to ngCCT (Volume: 418 ± 747 vs 332 ± 597; Mass: 89 ± 151 vs 78 ± 141; Agatston: 481 ± 854 vs 428 ± 776; P < 0.05). The correlation between the two values was always very high (Volume: r = 0.95; Mass: r = 0.97; Agatston: r = 0.98). Of the 6 patients with 0 Agatston score on gCCT, 2 (33%) showed an Agatston score > 0 in the ngCCT. Of the 3 patients with 1-10 Agatston score on gCCT, 1 (33%) showed an Agatston score of 0 in the ngCCT. Overall, 23 (38%) patients were reclassified in a different cardiovascular risk category, mostly (18/23; 78%) shifting to a lower risk in the ngCCT. The estimated radiation dose was significantly higher for gCCT (DLP 115.8 ± 50.7 vs 83.8 ± 16.3; Effective dose 1.6 ± 0.7 mSv vs 1.2 ± 0.2 mSv; P < 0.01).

CONCLUSION: CACS assessment is feasible on ngCCT; the variability of CACS values and the associated re-stratification of patients in cardiovascular risk groups should be taken into account.

Keywords: Coronary artery calcium score, Lung cancer screening, High-resolution computed tomography, Unenhanced chest computed tomography, Cardiovascular risk stratification

Core tip: Low dose chest computed tomography (CT)/high-resolution CT (HRCT) is entering the clinical practice for the screening of individuals at high risk of lung cancer. This study provides evidence that a surrogate stratification of cardiovascular risk can be performed on low-dose chest CT performed in the settings of lung cancer screening. This finding has some relevant consequences since lung cancer and atherosclerosis share some similarities concerning risk factors (smoking), patients’ population (age decade and gender prevalence).