Incremental prognostic value of coronary computed tomographic angiography high-risk plaque characteristics in newly symptomatic patients.

Background: The incremental prognostic value of the plaque features in coronary computed tomographic angiography (CTA) has not been well assessed. This study was designed to determine whether CTA high-risk plaques have prognostic value incremental to the Framingham risk score (FRS) and the severity of luminal obstruction.

Methods: A total of 628 newly symptomatic patients without known coronary artery disease underwent CTA.

Prognostic Value of Coronary Computed Tomography (CT) Angiography and Coronary Artery Calcium Score Performed Before Revascularization.

Background: Cardiac events after revascularization are equally attributable to recurrence at site of culprit lesions and development of nonculprit lesions. We evaluated the hypothesis that coronary computed tomography (CT) angiography and coronary artery calcium score (CACS) performed before revascularization predicts cardiac events after treatment.

Methods And Results: Among 2238 consecutive patients without known coronary artery disease who underwent coronary CT angiography and CACS, 359 patients underwent revascularization within 30 days after CT; in 337 of 359 (93.

Subtraction coronary computed tomography in patients with severe calcification.

To investigate the clinical usefulness of subtraction coronary computed tomographic angiography (CCTA) in patients with severe calcification. A 320-row area detector CT system was used in this study. The subjects were 78 patients (47 men and 31 women, 739 years of age) with an Agatston score of >300 who were able to undergo prospective one-beat scanning during a single breath-hold.

[Clinical usefulness of low tube current scanning with full reconstruction and automatic patient motion correction (APMC) reconstruction in a prospective ECG-gated coronary CT angiography using 320-row area detector CT].

Purpose: The purpose of this study is to validate the clinical usefulness of Advanced Patient Motion Correction (APMC) reconstruction when motion artifacts were observed in a prospective ECG-gated coronary CT angiography (CCTA), which was acquired by low tube current scanning with full reconstruction using 320-row area detector CT (0.275 s/rot.).

Segmental distributions of calcifications and non-assessable lesions on coronary computed tomographic angiography: evaluation in symptomatic patients.

Purpose: To clarify the frequency and distribution pattern of calcifications in all and in only non-assessable coronary arterial segments in symptomatic patients with coronary heart disease.

Materials And Methods: Among 2355 consecutive coronary CT angiographies performed using a 320-row ADCT, 1129 studies performed by prospective one-beat scanning without metallic and motion artifacts were evaluated. Frequency and degree of calcification were assessed for each coronary segment.

Repeat coronary computed tomographic angiography in patients with a prior scan excluding significant stenosis.

Background: ACCF/SCCT/ACR/AHA/ASE/ASNC/NASCI/SCAI/SCMR 2010 Appropriate Use Criteria for Cardiac Computed Tomography (AUC2010) does not incorporate prior coronary computed tomographic angiography (CCTA) results in the appropriateness of a CCTA examination. The purpose of this study was to explore the criteria for forgoing repeat CCTA among patients with clinical scenarios suggesting CCTA as appropriate after prior CCTA excluding coronary artery disease.

Methods And Results: Among patients from a single center (February 2006 to April 2013) who underwent appropriate CCTA based on AUC2010, consecutive 555 CCTAs, which had a prior CCTA excluding significant stenosis (>50% stenosis in diameter), were selected.

Overestimation of pretest probability of coronary artery disease by Duke clinical score in patients undergoing coronary CT angiography in a Japanese population.

Background: The Duke clinical score (DCS) is commonly used to estimate the pretest probability of coronary artery disease (CAD). However, the criterion was developed in a population undergoing catheter angiography.

Objective: To test the hypothesis that DCS overestimates the CAD probability when applied to patients evaluated with coronary CT angiography (CCTA).

Development of new risk score for pre-test probability of obstructive coronary artery disease based on coronary CT angiography.

Existing methods to calculate pre-test probability of obstructive coronary artery disease (CAD) have been established using selected high-risk patients who were referred to conventional coronary angiography. The purpose of this study is to develop and validate our new method for pre-test probability of obstructive CAD using patients who underwent coronary CT angiography (CTA), which could be applicable to a wider range of patient population. Using consecutive 4137 patients with suspected CAD who underwent coronary CTA at our institution, a multivariate logistic regression model including clinical factors as covariates calculated the pre-test probability (K-score) of obstructive CAD determined by coronary CTA.

Technical note: Electrocardiogram electrode repositioning for 320-row coronary CT angiography in patients with regular and recurrent premature ventricular contractions.

Arrhythmias can compromise image quality and increase radiation exposure during coronary CT angiography (CTA). However, premature ventricular contractions (PVCs) can occur in a predictable recurrent and regular pattern (ie, bigeminy, trigeminy, quadrigeminy) with post-PVC compensatory pauses. Electrocardiographic (ECG) electrode repositioning can achieve relative amplification of the R waves of PVCs compared with R waves of sinus beats.

Prospective ECG-gated coronary 320-MDCT angiography with absolute acquisition delay strategy for patients with persistent atrial fibrillation.

Objective: The purpose of this study was to evaluate image quality and radiation dose when patients with atrial fibrillation undergo coronary CT angiography (CTA) using prospectively ECG-gated 320-MDCT technology with an absolute-delay strategy.

Materials And Methods: A cohort of 75 consecutive patients (60 men and 15 women; age (± SD), 71 ± 10 years) who underwent prospectively ECG-gated coronary CTA using a 320-MDCT scanner during atrial fibrillation was matched with 75 control patients imaged in sinus rhythm. All coronary CTA for the atrial fibrillation cohort used absolute-delay strategy.

Motion artifacts on coronary CT angiography images in patients with a pericardial effusion.

Background: Patients with a pericardial effusion can have a pendulum-like movement of the heart. No reports associate the presence of pericardial fluid with coronary CT angiography (CTA) images that are degraded by motion artifact.

Objective: We tested the hypothesis that patients with pericardial effusion have coronary CTA images compromised by motion artifacts, even when other known causes of motion artifact in coronary imaging are minimized.

Image quality and radiation dose stratified by patient heart rate for coronary 64- and 320-MDCT angiography.

OBJECTIVE. The purpose of this study is to retrospectively measure and compare estimated radiation doses between consecutive patient cohorts who underwent coronary imaging CT with 64- and 320-MDCT scanners. MATERIALS AND METHODS.

[Prospective electrocardiogram gated coronary 320-row area detector computed tomography angiography using low tube current scanning with full reconstruction].

Background: It is possible to obtain equivalent image quality and a lower radiation dose using low tube current scanning with full reconstruction as compared to usual tube current scanning with half reconstruction in a 320-row area detector computed tomography (ADCT) angiography.

Method: Of 589 patient underwent coronary CT angiography (CCTA), 11 patients with (RR-PQ) ≥1069 ms were enrolled. In those patients, low tube current (50% mA) scanning with full or half reconstruction were performed.

[Comparison of the probability of meeting up with premature contraction during scanning in 320-area detector computed tomography with that in 64-multidetector CT coronary angiography].

Background: Because coronary computed tomography angiography (CCTA) by 320-area detector CT (320-ADCT) can be obtained in a short time, the probability of meeting up with premature contraction (PC) during scanning may be lower in 320-ADCT compared to 64-MDCT. The purpose is to compare the probability of meeting up with PC, scanning time, and image quality in patients with PC between the 2 groups (320-ADCT vs 64-MDCT).

Methods: We have never rejected any CCTA examination due to arrhythmias.

Coronary computed tomography angiography-based coronary risk stratification in subjects presenting with no or atypical symptoms.

Background:  Coronary computed tomography angiography (CTA) findings of positive vessel remodeling and low-attenuation plaque, referred to as computed tomography-verified high-risk plaque (CT-HRP), have been reported to be associated with the development of subsequent acute coronary syndromes. The aim of this study was to examine the usefulness of coronary CTA for coronary risk re-stratification of patients with asymptomatic and atypical chest symptoms.

Methods And Results:  A total of 1,139 subjects (M/F 602/537; mean age, 61.

Computed tomographic angiography-verified plaque characteristics and slow-flow phenomenon during percutaneous coronary intervention.

Objectives: This study sought to identify whether computed tomographic angiographic (CTA) plaque characteristics are associated with slow-flow phenomenon (SF) during percutaneous coronary intervention (PCI).

Background: SF during PCI is associated with myocardial damage and prolonged hospitalization. Intracoronary ultrasound-verified large echolucent lesions have been reported to predict SF.

Evaluation of plaque morphology by coronary CT angiography.

Coronary computed tomographic angiography (CTA) is a promising noninvasive tool that allows the visualization of plaque morphology. Plaques characterized by positive remodeling, low attenuation, and napkin ring circular enhancement on contrast-enhanced coronary CTA have been regarded as rupture-prone vulnerable plaques, which account for about 60% of all vulnerable lesions and may be precursors of plaque rupture. In this article, the authors discuss the various features related to plaque morphology that are essential to detect vulnerable plaques while performing coronary CTA.

[Reconstruction of coronary 64-multidetector-row computed tomography angiography in patients with atrial fibrillation: delete short RR intervals using electorocardiogram].

Background: The image qualities of coronary 64-multidetector-row computed tomography angiography (CCTA) in patients with atrial fibrillation (Afib) are often not enough. This study clarifies how to use electrocardiogram (ECG) -editing in Afib.

Methods: We performed CCTA (Aquilion 64 with beam pitch: 0.

[Estimation of radiation dose and image quality of coronary 320-row area detector CT angiography by optimal prospective ECG-gated protocols for different heart rate].

The purpose of this study is to estimate radiation dose and image quality of ECG-gated coronary 320-area detector CT (ADCT) angiography which was acquired using the protocols that were considered as optimal methods for different heart rates (HR) in 1031 consecutive patients (M/F=580/451, 65 ± 12 yr) without arrhythmias. We set up 5 protocols for 320-ADCT based on the relationship among heart rates, temporal resolution, gantry rotation speed, optimal reconstruction phase and slow filling phase on 64-multidetector-row computed tomography (MDCT), ie, 1) mid-diastolic (75% of RR) 1 beat scan (MD 1 beat, N=761(73.8%)) for HR ≤ 60, 2) mid-diastolic (75% of RR) 2 beat scan (MD 2 beat, N=135) for 61 ≤ HR ≤ 65, 3) end-systolic and mid-diastolic (37-80% of RR) 2 beat scan (ES-MD 2 beat, N=92) for 66 ≤ HR ≤ 75, 4) end-systolic (R+280-430 ms) 2 beat scan (ES 2 beat, N=21) for 76 ≤ HR ≤ 80, and 5) end-systolic (R+250-400 ms) 3 beat scan (ES 3 beat, N=22) for 81 ≤ HR ≤ 105.

[Relationship among RR interval, optimal reconstruction phase, temporal resolution, and image quality of end-systolic reconstruction of coronary CT angiography in patients with high heart rates: in search of the optimal acquisition protocol].

The purpose of this study is to elucidate the relationship among RR interval (RR), the optimal reconstruction phase, and adequate temporal resolution (TR) to obtain coronary CT angiography images of acceptable quality using 64-MDCT (Aquilion 64) of end-systolic reconstruction in 407 patients with high heart rates. Image quality was classified into 3 groups [rank A (excellent): 161, rank B (acceptable): 207, and rank C (unacceptable): 39 patients]. The optimal absolute phase (OAP) significantly correlated with RR [OAP (ms)=119-0.

Prevalence of computed tomographic angiography-verified high-risk plaques and significant luminal stenosis in patients with zero coronary calcium score.

Background: Some patients were detected with coronary artery disease even if the coronary artery calcium score was (CACS)=0. We evaluated the prevalence and predictor of significant stenosis and computed tomography (CT) based vulnerable plaque (CTVP) for patients with CACS=0.

Methods: Subjects were 2160 patients (M/F=1110/1050, 64.

[Comparison of radiation dose reduction of prospective ECG-gated one beat scan using 320 area detector CT coronary angiography and prospective ECG-gated helical scan with high helical pitch (FlashScan) using 64 multidetector-row CT coronary angiography].

Background: A high radiation dose associated with 64 multidetector-row computed tomography (64-MDCT) is a major concern for physicians and patients alike. A new 320 row area detector computed tomography (ADCT) can obtain a view of the entire heart with one rotation (0.35 s) without requiring the helical method.

[Usefulness and safety of propranolol injection into vein for acquisition of coronary multidetector-row computed tomography].

Background: A low heart rate (HR), associated with a prolonged slow filling phase (SF), is necessary to obtain a high quality coronary CT at a low radiation dose with conventional 64 multidetector-row computed tomography (MDCT). The purpose of our study was to confirm the safety of injecting propranolol (2-10 mg) into the vein for lowering heart rate in patients requiring MDCT and to document the effect of the drug on HR, PQ and SF.

Method: Of 1290 consecutive patients who were initially considered for enrollment in the coronary MDCT study, 40 patients with atrial fibrillations, 3 with atrial flutters, and 13 with artificial pacemakers were excluded.

Prevalence of anomalous origin of coronary artery detected by multi-detector computed tomography at one center.

Background: Anomalous origin of coronary artery (AOCA) has been described by coronary angiography or autopsy. However the actual prevalence of such abnormalities is unknown. Multi-detector computed tomography (MDCT) offers the possibility to visualize AOCA non-invasively.

[What factors affected image quality in coronary multidetector-row computed tomography?].

Background: Although it is well known that we usually cannot acquire a high quality coronary MDCT in patients with arrhythmia or incomplete breath-hold, we sometimes also cannot obtain a high quality coronary MDCT in patients without arrhythmia or incomplete breath-hold.

Purpose: We studied what factors other than arrhythmia or incomplete breath-hold affected image quality.

Methods: Coronary MDCT and echocardiography were performed within one month in 2145 patients, and 452 cases of arrhythmia or 102 cases of incomplete breath-hold during scanning were eliminated.