Visual Ordinal Scoring of Coronary Artery Calcium on Contrast-Enhanced and Noncontrast Chest CT: A Retrospective Study of Diagnostic Performance and Prognostic Utility.

BACKGROUND. Current guidelines recommend visual evaluation of coronary artery calcium (CAC) on all nongated noncontrast chest CT examinations. However, chest CT examinations are often performed with contrast material administration. OBJECTIVE. The purpose of our study was to evaluate diagnostic performance, prognostic utility, and interobserver agreement of visual CAC assessment on chest CT performed for other indications. METHODS. This retrospective study included 260 patients (158 men, 102 women; mean age, 60 ± 11 [SD] years) who underwent both nongated chest CT (contrast-enhanced in 116 patients; noncontrast in 144 patients) and cardiac calcium score CT within a 12-month interval. A cardiothoracic radiologist visually assessed CAC on chest CT using an ordinal scale (absent, mild, moderate, or severe). Cardiac CT Agatston calcium scores were quantified according to established guidelines and were categorized as CAC absent (0), mild CAC (1-99), moderate CAC (100-299), or severe CAC (≥ 300). The diagnostic performance of chest CT for the presence of CAC was assessed using cardiac CT as the reference standard. Major adverse cardiac events (MACE) were assessed as a composite of cardiovascular death and myocardial infarction and were evaluated using Cox proportional hazards models. A second cardiothoracic radiologist performed visual CAC assessments in a random subset of 50 chest CT examinations to assess interob-server agreement. RESULTS. For the presence of any CAC on cardiac CT, contrast-enhanced and non-contrast chest CT had sensitivity of 83% (62/75) and 89% (85/95) (p = .20) and specificity of 100% (41/41) and 100% (49/49) (p = .99). CAC present on cardiac CT was misclassified as absent on 13 contrast-enhanced and 10 noncontrast chest CT examinations; Agatston score was less than 30 in all such patients, and none experienced any MACE. The visual ordinal CAC score was associated with MACE for contrast-enhanced chest CT (hazard ratio [HR] = 4.5 [95% CI, 1.2-16.4], p = .02) and noncontrast chest CT (HR = 3.4 [95% CI, 1.5-7.8], p = .003). Interobserver agreement was excellent for contrast-enhanced (κ = 0.89) and noncontrast (κ = 0.95) chest CT. CONCLUSION. Visual ordinal CAC assessment on both contrast-enhanced and non-contrast chest CT has high diagnostic performance, prognostic utility, and interobserver agreement. CLINICAL IMPACT. Routine reporting of CAC on all chest CT examinations regardless of clinical indication and contrast material administration could identify a large number of patients with previously unknown CAC who might benefit from preventive treatment.

Variability in echocardiography and MRI for detection of cancer therapy cardiotoxicity.

OBJECTIVES: To compare variability of echocardiographic and cardiovascular magnetic resonance (CMR) measured left ventricular (LV) function parameters and their relationship to cancer therapeutics-related cardiac dysfunction (CTRCD). METHODS: We prospectively recruited 60 participants (age: 49.8±11.6 years), 30 women with human epidermal growth factor receptor 2-positive breast cancer (15 with CTRCD and 15 without CTRCD) and 30 healthy volunteers. Patients were treated with anthracyclines and trastuzumab. Participants underwent three serial CMR (1.5T) and echocardiography studies at ~3-month intervals. Cine-CMR for LV ejection fraction (LVEF), myocardial tagging for global longitudinal strain (GLS) and global circumferential strain (GCS), two-dimensional (2D) echocardiography for strain and LVEF and three-dimensional (3D) echocardiography for LVEF measurements were obtained. Temporal, interobserver and intraobserver variability were calculated as the coefficient of variation and as the SE of the measurement (SEM). Minimal detected difference (MDD) was defined as 2xSEM. RESULTS: Patients with CTRCD demonstrated larger mean temporal changes in all parameters compared with those without: 2D-LVEF: 4.6% versus 2.8%; 3D-LVEF: 5.2% vs 2.3%; CMR-LVEF: 6.6% versus 2.7%; 2D-GLS: 1.9% versus 0.7%, 2D-GCS: 2.5% versus 2.2%; CMR-GCS: 2.7% versus 1.6%; and CMR-GLS: 2.1% versus 1.4%, with overlap in 95% CI for 2D-LVEF, 2D-GCS, CMR-GLS and CMR-GCS. The respective mean temporal variability/MDD in healthy volunteers were 3.3%/6.5%, 1.8%/3.7%, 2.2%/4.4%, 0.8%/1.5%, 1.9%/3.7%, 1.8%/3.6% and 1.4%/2.8%. Although the mean temporal variability in healthy volunteers was lower than the mean temporal changes in CTRCD, at the individual level, 2D-GLS, 3D-LVEF and CMR-LVEF had the least overlap. 2D-GLS and CMR-LVEF had the lowest interobserver/intraobserver variabilities. CONCLUSION: Temporal changes in 3D-LVEF, 2D-GLS and CMR LVEF in patients with CTRCD had the least overlap with the variability in healthy volunteers; however, 2D-GLS appears to be the most suitable for clinical application in individual patients.