Title

Xenetix® 350: Comparative Assessment of Image Quality for Coronary CT Angiography
Xenetix® 350: Comparative Assessment of Image Quality for Coronary CT Angiography (X-ACT Study)
  • Phase

    Phase 4
  • Study Type

    Interventional
  • Study Participants

    468
The purpose of this study is to demonstrate the (statistical) non-inferiority of iobitridol (Xenetix® 350) when compared to contrast agents with higher iodine concentrations, iopromide (Ultravist® 370) and iomeprol (Iomeron® 400) in terms of coronary CT scan evaluability (quality and interpretability of images).
Patients suspected of coronary artery disease were submitted to coronary CT angiography using either iobitridol or contrast agents with higher iodine concentrations (iopromide or iomeprol). Independent off-site readers evaluated image quality regarding the ability to identify coronary artery stenosis (score 0- non evaluable to 4- excellent quality). The study was aimed at showing the non-inferiority of iobitridol in its ability to provide evaluable CT scans for the identification of coronary stenosis.
Study Started
Nov 30
2010
Primary Completion
Sep 30
2012
Study Completion
Sep 30
2012
Results Posted
Dec 16
2015
Estimate
Last Update
Dec 16
2015
Estimate

Drug iobitridol

single IV injection

  • Other names: Xenetix®

Drug iopromide

Single IV injection

  • Other names: Ultravist®

Drug iomeprol

Single IV injection

  • Other names: Iomeron®

Iobitridol Experimental

Patients were IV injected with a single dose of iobitridol before a coronary CT angiography

Iopromide Active Comparator

Patients were IV injected with a single dose of iopromide before a coronary CT angiography

Iomeprol Active Comparator

Patients were IV injected with a single dose of iomeprol before a coronary CT angiography

Criteria

Inclusion Criteria:

Male or female adult patient (having reached legal majority age)
Symptomatic patient suspected for coronary artery disease scheduled for a coronary CT angiography

Exclusion Criteria:

Patient with a heart rate > 65 beats per minute (bpm) and contraindication or intolerance to b-blocker administration
Patient with arrhythmia or non-sinus rhythm
Patient with decompensated heart failure
Patient with evidence of ongoing or active clinical instability (suspected or known acute myocardial infarction, cardiac shock, acute pulmonary oedema)
Patient who has previously undergone coronary artery bypass graft
Patient who has previously undergone percutaneous transluminal coronary stent placement
Patient with artificial heart valve
Patient with known moderate to severe aortic stenosis

Summary

Iobitridol

Iopromide

Iomeprol

All Events

Event Type Organ System Event Term Iobitridol Iopromide Iomeprol

Rate of Patients With Evaluable CT Scans i.e. Allowing Identification of Coronary Artery Stenosis According to Off-site Reading Assessment

Evaluability was based upon the off-site assessment of 18-coronary segments graded for image quality with a 5-point scale.4= Excellent quality, fully confidence without any doubts concerning the presence/absence of luminal stenosis; 3= Good quality, confidence concerning the presence/absence of luminal stenosis; 2= Moderate quality, relative confidence, with minor doubts concerning the presence/absence of luminal stenosis; 1= Poor quality, some doubts concerning the presence/absence of stenosis; 0= Non diagnostic. A patient's CT scan was considered as evaluable for identification of coronary artery stenosis if none of the 18 coronary segments had a score of 0.

Iobitridol

92.1
Percentage of patients (Geometric Mean)
Standard Error: 2.2

Iopromide

95.4
Percentage of patients (Geometric Mean)
Standard Error: 1.7

Iomeprol

94.6
Percentage of patients (Geometric Mean)
Standard Error: 1.8

Average Image Quality According to Off-site Reading

For each patient, all 18 coronary segments were graded for image quality using a 5-point evaluation scale (from 0=non-diagnostic to 4=excellent). The average image quality was evaluated using the off-site readings, by averaging the scores obtained for the 18 segments used to determine the CT evaluability (primary criteria).

Iobitridol

3.5
Image quality Score on a scale (Mean)
Standard Deviation: 0.9

Iopromide

3.5
Image quality Score on a scale (Mean)
Standard Deviation: 0.8

Iomeprol

3.4
Image quality Score on a scale (Mean)
Standard Deviation: 0.9

Coronary Track Rate

A post processing software automatically tracked the number of distal segments of the left anterior descending coronary artery, the left circumflex coronary artery and the right coronary artery . The number of segments tracked per patient were assessed by an independent off-site radiologist.

Iopromide

10.8
Number of tracked segments per patient (Mean)
Standard Deviation: 2.4

Iomeprol

11.1
Number of tracked segments per patient (Mean)
Standard Deviation: 2.3

Iobitridol

10.9
Number of tracked segments per patient (Mean)
Standard Deviation: 2.2

Average Signal Attenuation After IV Injection of Contrast

Attenuation of signal was measured off-site on post-injection images of four coronary segments, in the ascending aorta and in the left ventricle, then it was averaged at the patient level.

Iobitridol

426.3
Hounsfield Units (Geometric Mean)
Standard Deviation: 92.9

Iopromide

449.8
Hounsfield Units (Geometric Mean)
Standard Deviation: 88.1

Iomeprol

466.4
Hounsfield Units (Geometric Mean)
Standard Deviation: 104.6

Average Signal-to-Noise Ratio (Average SNR)

Signal attenuation was measured by off-site radiologists in the lumen of 4 coronary segments, in the ascending aorta and in the left ventricle and was expressed in Hounsfield Unit (HU). Measurements were set in post-injection images for the 6 territories. A measure of noise in CT scans was collected at least in the aorta and if possible in the muscle and/or air. Signal-to-Noise Ratios (SNR) of post-injection images were derived in all territories from attenuation measurements according to the following formula: SNR Territory = Post Attenuation / Image Noise

Iobitridol

16.2
Hounsfield Units:Hounsfield Units (Mean)
Standard Deviation: 5.6

Iopromide

17.1
Hounsfield Units:Hounsfield Units (Mean)
Standard Deviation: 5.0

Iomeprol

17.6
Hounsfield Units:Hounsfield Units (Mean)
Standard Deviation: 6.6

Average Contrast-to-noise Ratio (Average CNR)

Signal attenuation was measured by off-site radiologists in the lumen of 4 coronary segments in the ascending aorta and the in left ventricle and expressed in Hounsfield Unit (HU). A measure of noise in CT scans was collected at least in the aorta and if possible in the muscle and/or air. In territories where pre and post signal attenuation measures were both available, the contrast-to-noise ratio was computed according to the following formula: CNR = (Post Att - Baseline Att) / Image Noise

Iobitridol

14.4
Hounsfield Units:Hounsfield Units (Mean)
Standard Deviation: 5.4

Iopromide

15.3
Hounsfield Units:Hounsfield Units (Mean)
Standard Deviation: 4.8

Iomeprol

15.8
Hounsfield Units:Hounsfield Units (Mean)
Standard Deviation: 6.5

Total

468
Participants

Age, Continuous

57.8
years (Mean)
Standard Deviation: 12.4

Age, Categorical

Region of Enrollment

Sex: Female, Male

Overall Study

Iobitridol

Iopromide

Iomeprol

Drop/Withdrawal Reasons

Iobitridol

Iopromide

Iomeprol