Coronary spiral CT

This dissertation describes the use and clinical potential of ECG gated multislice spiral computed tomography in patients with coronary artery disease. First the use of other non invasive cardiac imaging, i.e. the previously mentioned electron beam CT and magnetic resonance imaging is reviewed (chapter 2.1). Part 3 contains studies related to the characteristics of multislice spiral CT for the imaging of the heart and coronary arteries, and the diagnostic potential of ECG gated spiral CT coronary angiography to detect and visualize obstructive coronary artery disease in symptomatic patients, using conventional coronary angiography as the standard of reference. Part 4 is focussed on the feasibility and characteristics of coronary wall imaging by CT, including the assessment of non calcified atherosclerotic plaque material. The usefulness of contrast enhanced multislice spiral CT in symptomatic patients who previously underwent coronary artery bypass grafting and percutaneous coronary intervention with stent implantation is discussed in part 5. Finally, the first results with the latest generation 16 slice computed tomography scanners and patient preparation with ~ receptor blockers are described in part 6, including a review and future outlook on the continuing development and clinical use of non invasive coronary angiography with spiral computed tomography

Low-dose coronary calcium scoring CT using a dedicated reconstruction filter for kV-independent calcium measurements

In this prospective, pilot study, we tested a kV-independent coronary artery calcium scoring CT protocol, using a novel reconstruction kernel (Sa36f). From December 2018 to November 2019, we performed an additional research scan in 61 patients undergoing clinical calcium scanning. For the standard protocol (120 kVp), images were reconstructed with a standard, medium-sharp kernel (Qr36d). For the research protocol (automated kVp selection), images were reconstructed with a novel kernel (Sa36f). Research scans were sequentially performed using a higher (cohort A, n = 31) and a lower (cohort B, n = 30) dose optimizer setting within the automatic system with customizable kV selection. Agatston scores, coronary calcium volumes, and radiation exposure of the standard and research protocol were compared. A phantom study was conducted to determine inter-scan variability. There was excellent correlation for the Agatston score between the two protocols (r = 0.99); however, the standard protocol resulted in slightly higher Agatston scores (29.4 [0-139.0] vs 17.4 [0-158.2], p = 0.028). The median calcium volumes were similar (11.5 [0-109.2] vs 11.2 [0-118.0] mm(3); p = 0.176), and the number of calcified lesions was not significantly different (p = 0.092). One patient was reclassified to another risk category. The research protocol could be performed at a lower kV and resulted in a substantially lower radiation exposure, with a median volumetric CT dose index of 4.1 vs 5.2 mGy, respectively (p < 0.001). Our results showed that a consistent coronary calcium scoring can be achieved using a kV-independent protocol that lowers radiation doses compared to the standard protocol

Functional evaluation of coronary disease by CT angiography

Publisher Copyright: © 2015 American College of Cardiology Foundation.In recent years, several technical developments in the field of cardiac computed tomography (CT) have made possible the extraction of functional information from an anatomy-based examination. Several different lines have been explored and will be reviewed in the present paper, namely: 1) myocardial perfusion imaging; 2) transluminal attenuation gradients and corrected coronary opacification indexes; 3) fractional flow reserve computed from CT; and 4) extrapolation from atherosclerotic plaque characteristics. In view of these developments, cardiac CT has the potential to become in the near future a truly 2-in-1 noninvasive evaluation for coronary artery disease.publishersversionpublishe

Prognostic Value of Subclinical Coronary Artery Disease in Atrial Fibrillation Patients Identified by Coronary Computed Tomography Angiography

Identifying coronary artery disease (CAD) in atrial fibrillation (AF) patients improves risk stratification and defines clinical management. However, the value of screening for subclinical CAD with cardiac CT in AF patients is unknown. Between 2011 and 2015, 94 consecutive patients without known or suspected CAD (66 (57–73) years, 68% male), who were referred for AF evaluation, under

Undetectable High-Sensitivity Troponin T as a Gatekeeper for Coronary Computed Tomography Angiography in Patients Suspected of Acute Coronary Syndrome

OBJECTIVES: The aim of this study was to characterize the safety and efficiency of a strategy employing the limit of detection (LoD) of high-sensitivity troponin T (hs-TnT) as a gatekeeper for coronary computed tomography angiography (CCTA) in suspected acute coronary syndrome (ACS) patients in the emergency department (ED). METHODS: We included suspected ACS patients who underwent CCTA and were evaluated with hs-TnT. Patients were categorized as below the LoD and at or above the LoD. The primary outcome was 30-day major adverse cardiac events (MACEs), defined as all-cause mortality, ACS, or coronary revascularization. RESULTS: The study population consisted of 177 patients (mean age 55 ± 10 years, 50.3% women), and 16 (9.0%) patients reached the primary outcome. None of the patients died, while 13 had an adjudicated diagnosis of ACS, and 3 underwent elective coronary revascularization. There were 77 patients (44%) with an hs-TnT value below the LoD (MACEs; n = 1 [1.3%]) and 100 (56%) with at or above the LoD levels (MACEs; n = 15 [15%]). None of 67 patients with an hs-TnT value below the LoD and <50% stenosis on CCTA experienced MACEs. Out of the 10 patients with an hs-TnT value below the LoD and ≥50% stenosis on CCTA, 1 patient underwent elective percutaneous coronary revascularization. In patients with an hs-TnT value at or above the LoD, 74 patients had <50% stenosis on CCTA, and 2 patients (3%) were diagnosed with myocardial infarction without obstructive coronary artery disease confirmed on invasive angiography. Thirteen (50%) patients with an hs-TnT value at or above the LoD and ≥50% stenosis on CCTA experienced MACEs (11 ACS and 2 elective percutaneous coronary revascularizations). CONCLUSION: Our findings support that implementing the LoD of hs-TnT as a gatekeeper may reduce the need for CCTA in suspected ACS patients in the ED