Low-Dose Contrast CT for TAVR Planning

(CT TAVR Trial)

Overseen By Rosy Njonkou, M.S.

Age: 18+

Sex: Any

Trial Phase: Phase 4

Sponsor: University of Maryland, Baltimore

Disqualifiers: Allergy to contrast, GFR<30, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Prior Safety Data This treatment has passed at least one previous human trial

Approved in 6 Jurisdictions This treatment is already approved in other countries

Compensation: Varies

Number of Visits: Unknown

Duration: 18-24 months

164 Participants Needed

Trial Summary

What is the purpose of this trial?

A standard polyenergetic CT (computed tomography) procedure utilizes 100 ml of iodinated contrast. A recent world-wide shortage of iodine based intravenous contrast has highlighted the need to search for alternative methods or doses. Reducing iodinated IV contrast dose can mitigate IV contrast supply shortages and enable significant cost savings for the radiology practice and hospital system. In addition, decreased IV contrast dose can potentially reduce the rate of acute kidney injury, specifically in patients with decreased renal function. The purpose of the study is to determine whether low IV contrast dose CT with monoenergetic reconstruction can be use for presurgical planning of transcatheter valve replacement (TAVR) procedure.

Will I have to stop taking my current medications?

The trial information does not specify whether you need to stop taking your current medications.

What data supports the effectiveness of the treatment Dual Energy CT, Dual Energy Computed Tomography, DECT, Omnipaque, Iohexol for TAVR Planning?

Dual Energy CT (DECT) has been shown to enhance image quality by improving contrast between different tissues, which can be beneficial in various medical imaging applications, including cardiac imaging. Additionally, DECT allows for reduced use of iodinated contrast agents, like Omnipaque (Iohexol), while maintaining image quality, which can be advantageous in reducing potential side effects from contrast use. ^{1 2 3 4 5}

Is low-dose dual-energy CT generally safe for humans?

Research on dual-energy CT (DECT) shows it can reduce radiation exposure compared to traditional CT methods, which suggests it is generally safe for humans. Studies have focused on reducing metal artifacts and radiation doses, indicating safety improvements in imaging techniques. ^{2 6 7 8 9}

How is the treatment Dual Energy CT (DECT) for TAVR planning different from other treatments?

Dual Energy CT (DECT) is unique because it uses two X-ray energy levels to enhance image contrast and reduce the amount of iodinated contrast needed, which can be beneficial for patients with kidney issues. This approach allows for clearer images with less radiation exposure compared to traditional single-energy CT scans. ^{1 4 6 10 11}

Eligibility Criteria

This trial is for patients scheduled to undergo a CT scan of the abdomen as part of planning for their transcatheter aortic valve replacement (TAVR) procedure. Participants must be able to have a CT scan and not have severely reduced kidney function (GFR<30) or an uncontrolled allergy to IV contrast, even with steroids or Benadryl.

Inclusion Criteria

I am scheduled for a CT scan before my heart valve replacement.

Exclusion Criteria

My kidney function is low.

Cannot undergo CT scan

Allergy to intravenous contrast not controlled by steroids or benadryl

Timeline

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants receive reduced doses of iodinated contrast for CT imaging to assess diagnostic quality

18-24 months

Follow-up

Participants are monitored for safety and effectiveness after treatment

4 weeks

Treatment Details

Interventions

• Dual Energy CT
• Omnipaque

Trial Overview The study is testing if using a lower dose of iodinated contrast agent (Omnipaque) during dual-energy CT scans can still provide clear images for TAVR surgery planning. This could help conserve contrast material, reduce costs, and potentially decrease the risk of kidney injury in vulnerable patients.

Participant Groups

Group I: Cohort 2 Experimental Treatment 2 Interventions

If imaging with 1/3 dose is satisfactory, a second cohort with 1/4th the standard dosage (25 ml) will be assessed. If images are not satisfactory, contrast dose will be increased to 50 ml.

Group II: Cohort 1 Experimental Treatment 2 Interventions

A cohort will be given a 1/3rd reduced dose of iodinated contrast agent (33 ml).

Dual Energy CT is already approved in European Union, United States, Canada, Japan, China, Switzerland for the following indications:

Approved in European Union as Dual Energy CT for:

• Cardiovascular imaging
• TAVR planning

Approved in United States as Dual Energy CT for:

• Cardiovascular imaging
• TAVR planning

Approved in Canada as Dual Energy CT for:

• Cardiovascular imaging
• TAVR planning

Approved in Japan as Dual Energy CT for:

• Cardiovascular imaging
• TAVR planning

Approved in China as Dual Energy CT for:

• Cardiovascular imaging
• TAVR planning

Approved in Switzerland as Dual Energy CT for:

• Cardiovascular imaging
• TAVR planning

Who Is Running the Clinical Trial?

University of Maryland, Baltimore

Lead Sponsor

Trials

729

Recruited

540,000+

Findings from Research

Dual energy CT (DECT) technology, which uses two X-ray sources of different energies, significantly improves the contrast between adjacent structures, making it particularly useful in cardiac imaging due to its higher temporal resolution.

DECT can also enhance imaging in other areas such as craniocervical and peripheral vasculature, allowing for better differentiation of vascular lumina from calcified plaques, and it shows promise in characterizing ureteric stones and evaluating hepatic lesions, potentially leading to dose savings in imaging procedures.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Dual Energy CT and its use in neuroangiography. Hegde, A., Chan, LL., Tan, L., et al.[2020]

Low-dose dual-energy computed tomography (DECT) significantly reduces metallic artifacts from orthopedic devices compared to both dose-neutral DECT and dose-reduced single-energy computed tomography (SECT), based on a study involving 30 implants in 20 cadavers.

The optimized monoenergetic DECT images (OPTkeV) provided superior image quality, especially at lower doses, demonstrating that low-dose DECT can achieve artifact reduction similar to neutral-dose DECT while outperforming reduced-dose SECT.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Performances of low-dose dual-energy CT in reducing artifacts from implanted metallic orthopedic devices. Filograna, L., Magarelli, N., Leone, A., et al.[2022]

Dual-energy CT (DECT) offers significant advantages in clinical imaging, such as material decomposition and the ability to eliminate misregistration artifacts, enhancing the accuracy of diagnoses across various applications including neurology, thorax, and abdominal imaging.

DECT can replace traditional unenhanced images by generating virtual non-contrast images, allowing for improved characterization of conditions like liver and pancreas masses, and even differentiating between types of urinary calculi, making it a versatile tool in medical imaging.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Dual-energy CT revisited with multidetector CT: review of principles and clinical applications. Karçaaltıncaba, M., Aktaş, A.[2022]

A dual energy CT (DECT) protocol using 50% less iodinated contrast provided adequate image quality for imaging the thoracic aorta, comparable to standard single energy CT (SECT) in 14 patients.

The best image quality was achieved with DECT using ASIR-V 80% reconstructions at 55 keV, although the increased radiation dose associated with DECT may limit its use in certain patients.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The potential of iodinated contrast reduction in dual-energy CT thoracic angiography; an evaluation of image quality. Johansen, CB., Martinsen, ACT., Enden, TR., et al.[2022]

Dual energy CT (DECT) enhances imaging by using two energy spectra to differentiate materials with similar CT attenuation, allowing for improved detection and quantification of substances like iodine and uric acid, which is particularly useful in emergency settings.

Recent advances in DECT technology have expanded its clinical applications, including differentiating types of intracranial hemorrhage, diagnosing pulmonary embolism, and identifying uric acid stones, making it a valuable tool for emergency radiologists.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Dual Energy CT Physics-A Primer for the Emergency Radiologist. Odedra, D., Narayanasamy, S., Sabongui, S., et al.[2023]

Dual-energy computed tomography (DECT) aortography using a 70% reduced iodine dose provides similar aortic attenuation and image quality compared to standard single-energy CT (SECT) aortography with a full iodine dose, based on a study of 21 patients.

Despite a significant reduction in iodine dose, DECT showed acceptable subjective image quality, although slightly lower than SECT, indicating that DECT could be a safer alternative with reduced iodine exposure while maintaining diagnostic efficacy.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Prospective comparison of dual-energy CT aortography using 70% reduced iodine dose versus single-energy CT aortography using standard iodine dose in the same patient. Shuman, WP., O'Malley, RB., Busey, JM., et al.[2018]

Dual-energy CT (DECT) significantly reduces metal-related artifacts in head CT angiography, particularly for patients with surgical clips, as shown in a study of 13 patients.

The study found that noise levels were lower at higher photon energy levels and that coils produced more artifacts than clips, indicating that DECT is more effective for clips than for coils.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The utility of dual-energy CT for metal artifact reduction from intracranial clipping and coiling. Mera Fernández, D., Santos Armentia, E., Bustos Fiore, A., et al.[2021]

In a study of 860 children undergoing abdominopelvic exams, dual-energy computed tomography (DECT) was found to deliver lower radiation doses compared to conventional single-energy CT (SECT), with significant reductions in both size-specific dose estimates (SSDE) and volume CT dose index (CTDIvol).

The image quality of DECT was comparable to that of SECT across different patient sizes, indicating that DECT can be a safer alternative without compromising diagnostic quality.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Comparison of radiation dose and image quality between contrast-enhanced single- and dual-energy abdominopelvic computed tomography in children as a function of patient size. Siegel, MJ., Mhlanga, JC., Salter, A., et al.[2021]

In a study involving 100 patients with primary hyperparathyroidism, virtual non-contrast (VNC) images from dual-energy computed tomography (DECT) showed good agreement with true non-contrast (TNC) images for most neck anatomical structures, potentially reducing radiation exposure.

However, significant differences in CT density were observed in the thyroid gland, indicating that VNC images cannot fully replace TNC images when specifically examining the thyroid and surrounding tissues.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Can virtual non-contrast imaging replace true non-contrast imaging in multiphase scanning of the neck region? Al-Difaie, Z., Scheepers, MH., Bouvy, ND., et al.[2023]

Diagnostic dual energy CT (DECT) of the chest can be safely performed at submillisievert (sub-mSv) doses, achieving a mean effective dose of 0.7 mSv while maintaining good image quality in all 20 patients studied.

This study is the first to demonstrate that DECT can be conducted at such low radiation doses without losing relevant diagnostic information, indicating a significant advancement in imaging safety.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Submillisievert chest dual energy computed tomography: a pilot study. Canellas, R., Ackman, JB., Digumarthy, SR., et al.[2019]

Dual-energy computed tomography (DECT) offers advanced imaging capabilities by using two X-ray energy levels, allowing for better analysis of cerebrovascular diseases through techniques like virtual noncontrast and iodine overlay images.

DECT enhances the identification and differentiation of various cerebrovascular conditions, such as detecting active bleeding in intracranial hemorrhages and improving the assessment of atheromatous plaques, which can lead to more accurate diagnoses and treatment planning.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Principles and Clinical Application of Dual-energy Computed Tomography in the Evaluation of Cerebrovascular Disease. Hsu, CC., Kwan, GN., Singh, D., et al.[2020]

References

1. Singapore pubmed.ncbi.nlm.nih.gov

Dual Energy CT and its use in neuroangiography. [2020]

2. Germany pubmed.ncbi.nlm.nih.gov

Performances of low-dose dual-energy CT in reducing artifacts from implanted metallic orthopedic devices. [2022]

3. Turkey pubmed.ncbi.nlm.nih.gov

Dual-energy CT revisited with multidetector CT: review of principles and clinical applications. [2022]

4. Netherlands pubmed.ncbi.nlm.nih.gov

The potential of iodinated contrast reduction in dual-energy CT thoracic angiography; an evaluation of image quality. [2022]

5. Switzerland pubmed.ncbi.nlm.nih.gov

Dual Energy CT Physics-A Primer for the Emergency Radiologist. [2023]

6. United States pubmed.ncbi.nlm.nih.gov

Prospective comparison of dual-energy CT aortography using 70% reduced iodine dose versus single-energy CT aortography using standard iodine dose in the same patient. [2018]

7. Spain pubmed.ncbi.nlm.nih.gov

The utility of dual-energy CT for metal artifact reduction from intracranial clipping and coiling. [2021]

8. Germany pubmed.ncbi.nlm.nih.gov

Comparison of radiation dose and image quality between contrast-enhanced single- and dual-energy abdominopelvic computed tomography in children as a function of patient size. [2021]

9. England pubmed.ncbi.nlm.nih.gov

Can virtual non-contrast imaging replace true non-contrast imaging in multiphase scanning of the neck region? [2023]

10. England pubmed.ncbi.nlm.nih.gov

Submillisievert chest dual energy computed tomography: a pilot study. [2019]

11. United States pubmed.ncbi.nlm.nih.gov

Principles and Clinical Application of Dual-energy Computed Tomography in the Evaluation of Cerebrovascular Disease. [2020]