Effectiveness of Using Dual-source CT and the Upshot it creates on Both Heart Rate and Image Quality

Abstract

Background: Early detection of coronary artery disease (CAD) is important because of the high morbidity and mortality rates. As invasive coronary angiography (ICA) is an invasive procedure, an alternative diagnostic method; coronary computed tomography angiography (CTA), has become more widely used by the improvements in detector technology. Aims: In this study, we aimed to examine the accuracy and image quality of high-pitch 128-slice dual-source CTA taking the ICA as reference technique. We also aimed to compare the accuracy and image quality between different heart rate groups of >70 beates per minute (bpm) and ≤70 bpm. Study Design: Retrospective cross-sectional study. Methods: Among 450 patients who underwent coronary CTA with the FLASH spiral technique, performed with a second generation dual-source computed tomography device with a pitch value of 3.2, 102 patients without stent and/or bypass surgery history and clinically suspected coronary artery disease who underwent ICA within 15 days were enrolled. Image quality was assessed by two independent radiologists using a 4-point scale (1=absence of any artifacts-4=non-evaluable). A stenosis >50% was considered significant on a per-segment, per-vessel, and per-patient basis and ICA was considered the reference method. Radiation doses were determined using dose length product (DLP) values detected by the computed tomography (CT) device. In addition, patients were classified into two groups according to their heart rates as ≤70 bpm (73 patients) and >70 bpm (29 patients). The relation between the diagnostic accuracy and heart rate groups were evaluated. Results: Overall, 1495 (98%) coronary segments were diagnostic in 102 patients (32 male, 70 female, mean heart rate: 65 bpm). There was a significant correlation between image quality and mean heart rate in the right coronary artery (RCA) segments. The effective radiation dose was 0.98±0.09 mili Sievert (mSv). On a per-patient basis, sensitivity, specificity, and positive and negative predictive values were 93.8%, 88.8%, 93.8% and 88.8%, respectively. These values were also similar in per-vessel and per-segment basis. Two different groups categorized by mean heart rate had almost similar results in terms of the diagnostic power of dual-source CTA. Conclusion: CTA with a high pitch value is a reliable, non-invasive diagnostic method that can CAD with low radiation doses not only in patients with a heart rate below 70 bpm, but also in patients with higher heart rates. Keywords: Computed tomography angiography, coronary arteries, high-pitch, low radiation dose, heart rate Copyright 2016 © Trakya University Faculty of Medicine Balkan Med J 201633: 283-93 Effectiveness of Using Dual-source CT and the Upshot it creates on Both Heart Rate and Image Quality

Diagnostic performance of 256-row detector coronary CT angiography in patients with high heart rates within a single cardiac cycle: a preliminary study

“…In most cases of this study (80 of 84 patients, 95.2%), the entire heart could be scanned within a 140 mm. The mean ED of 1.9 mSv in this study is higher than that reported in some recent studies with mean ED less than 1.0mSv [28][29][30]. However, different modes of high-pitch with dual-source CT were used in those studies, also with inclusion of patients with different heart rates.…”

Diagnostic accuracy of prospectively gated, 128‐slice or greater CTCA at high heart rates: a systematic review and meta‐analysis

“…Insufficient data were provided by one study, and it was therefore excluded from the analysis. 19 Of the remaining studies, six contained patient‐level accuracy information and were included, as shown in Figure 3 .…”

“…4,[14][15][16] Four studies that reported patient-level diagnostic accuracy data were included in the review. [17][18][19][20] Whilst the primary aim of these studies was not to directly study high HRs, they provided subgroup data directly pertinent to the review question.…”

Recent advances in cardiac computed tomography dose reduction strategies: a review of scientific evidence and technical developments

“…63,70,83 Scanners with faster rotation times (better temporal resolution) or an increased number of x-ray sources permit higher heart rate cutoffs for prospectively ECG-triggered acquisition mode, which is associated with substantially lower radiation dose as compared with retrospectively ECG-gated acquisition mode. 63,70,83 Addition of "adaptive" or arrhythmia rejection feature in prospectively ECG-triggered acquisition mode enables the scanners to reject scanning in beats with irregular rhythm so that obtain diagnostic quality exams at reduced radiation dose even in patients with variable heart rates, such as atrial fibrillation. Without the arrhythmia rejection algorithms for prospectively ECG-triggered mode, patients with variable heart rates would require much higher radiation doses from retrospectively ECG-gated acquisition mode with conservative ECG-based tube current modulation.…”

“…66,67 High-pitch helical (HPH) acquisition mode with fast table speed and prospective ECG triggering enables coverage of the entire heart within one cardiac cycle. Several studies on HPH mode for CCTA in pediatric and adult populations 16,63,[68][69][70] have reported good diagnostic quality and consistently low mean radiation dose (0.8 to 1.3 mSv) ( Table 2). The HPH is particularly advantageous in children or young adults for assessment of coronary artery anomalies and anatomic assessment in patients with congenital heart disease (when information regarding cardiac function is not needed).…”