CCTA to Optimize the Diagnostic Yield of Invasive Angiography (CarDIA)

Coronary Computed Tomographic Angiography to Optimize the Diagnostic Yield of Invasive Angiography in Lower Risk Patients

This study aims to reduce patient risk and costs to the healthcare system by improving the diagnostic yield of invasive coronary angiography through existing triage processes to improve risk stratification using Coronary Computed Tomographic Angiography (CCTA) as a first step in low risk patients. All low-risk patients referred for invasive coronary angiography will be potentially eligible for CCTA instead of invasive angiography as a first-line diagnostic test. All CCTAs will be read by both a level 3-trained cardiologist and a radiologist. The results of the CCTA, coupled with evidence-based management recommendations will be sent to the referring physician and an invasive angiogram will be arranged by the HIU triage, only when clearly indicated

Study Overview

• Status: Completed
• Conditions: Coronary Artery Disease
• Intervention / Treatment: Diagnostic test: Coronary Computed Tomographic Angiography

• Study Type: Observational
• Enrollment (Actual): 186

Contacts and Locations

Study Locations

• Canada
  • Ontario
    • Hamilton, Ontario, Canada, L8L 2X2
      • Hamilton General Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 75 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Non-Probability Sample

Study Population

All eligible low-risk patients referred for invasive angiography will be recruited from the two interventional sites (approximately 240) via centralized triage process. Patients treated before the intervention implementation will be the control group (approximately 480).

Description

Inclusion Criteria:

1. Non urgent outpatient referral
2. Canadian Cardiovascular Society class I or II
3. Indication for invasive angiogram includes: Rule out Coronary Artery Disease (CAD) and Cardiomyopathy

Exclusion Criteria:

1. Age <18 years old, Men >65 years old or women >75 years old
2. Patient refusal to provide verbal consent for CCTA at time of triage contact or unable to provide informed consent
3. Referring physician refusal for their eligible patients to be approached for the CarDIA study
4. Any prior CCTA
5. Atrial Fibrillation
6. Creatinine > 150 mmol/L
7. Diabetes mellitus
8. High risk Exercise Stress Test or Functional Imaging
9. Known severe valvular disease being considered for valve surgery

10. Any known CAD

    • Prior Acute Coronary Syndrome (ACS)
    • Prior Percutaneous Coronary Intervention (PCI) or Coronary Artery Bypass Graft (CABG)

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Intervention Group; All low-risk patients referred for invasive coronary angiography through the Hamilton General Hospital's Heart Investigation Unit Triage will be potentially eligible to receive the intervention over a 12-month period. The intervention will include risk stratification with CCTA at HHS and NHS as an alternative to upfront invasive angiography.	Diagnostic test: Coronary Computed Tomographic Angiography; All low-risk patients referred for invasive coronary angiography will be potentially eligible to receive the intervention over a 12-month period. The intervention will include risk stratification using Coronary Computed Tomographic Angiography (CCTA) at HHS and NHS as an alternative to upfront invasive angiography. All CCTAs will be read by both a level 3-trained cardiologist and a radiologist. The results of the CCTA, coupled with evidence-based management recommendations will be sent to the referring physician and an invasive angiogram will be arranged only when indicated as per these management recommendations
Control Group; Intervention sites will act as their own controls: outcomes of all eligible patients in the 24-months prior to the implementation of the intervention will be assessed from a routinely collected health administrative database. Eligible patients not undergoing CCTA (patient or physician refusal, or CCTA not available) will be captured and included in the control group as part of a sensitivity analysis during the intervention period

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Diagnostic yield of invasive angiography	Diagnostic yield is defined as the proportion of invasive angiograms that identify significant disease (≥70% stenosis) on a major coronary vessel (>2 mm) or > 50% stenosis in the left main)	Three years

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Quantitative assessment of angiograms avoided	Number of angiograms avoided due to CCTA bookings	Three years
Deviation from management recommendations following CCTA	Number of angiograms performed when not recommended	Three years
Protocol deviation as a surrogate for acceptability of the novel triage program	Percentage of patients and physicians refusing to undergo CCTA as a first step	Three years
Costing of new strategy	Cost of risk stratification of Coronary Artery Disease in low risk patients	Three years

Collaborators and Investigators

• Sponsor: Hamilton Health Sciences Corporation
• Collaborators: Hamilton Academic Health Sciences Organization
• Investigators: Principal Investigator: Jon-David Schwalm, MD,FRCPC,Msc, Hamilton Health Sciences Corporation; Principal Investigator: Tej Sheth, Bsc,FRCPC,MD, Hamilton Health Sciences Corporation

Publications and helpful links

General Publications

• Patel MR, Peterson ED, Dai D, Brennan JM, Redberg RF, Anderson HV, Brindis RG, Douglas PS. Low diagnostic yield of elective coronary angiography. N Engl J Med. 2010 Mar 11;362(10):886-95. doi: 10.1056/NEJMoa0907272. Erratum In: N Engl J Med. 2010 Jul 29;363(5):498.
• Dewey M, Rief M, Martus P, Kendziora B, Feger S, Dreger H, Priem S, Knebel F, Bohm M, Schlattmann P, Hamm B, Schonenberger E, Laule M, Zimmermann E. Evaluation of computed tomography in patients with atypical angina or chest pain clinically referred for invasive coronary angiography: randomised controlled trial. BMJ. 2016 Oct 24;355:i5441. doi: 10.1136/bmj.i5441. Erratum In: BMJ. 2016 Nov 29;355:i6420.
• Roth GA, Forouzanfar MH, Moran AE, Barber R, Nguyen G, Feigin VL, Naghavi M, Mensah GA, Murray CJ. Demographic and epidemiologic drivers of global cardiovascular mortality. N Engl J Med. 2015 Apr 2;372(14):1333-41. doi: 10.1056/NEJMoa1406656.
• Sheth T, Amlani S, Ellins ML, Mehta S, Velianou J, Cappelli G, Yang S, Natarajan M. Computed tomographic coronary angiographic assessment of high-risk coronary anatomy in patients with suspected coronary artery disease and intermediate pretest probability. Am Heart J. 2008 May;155(5):918-23. doi: 10.1016/j.ahj.2007.11.035. Epub 2008 Feb 19.
• Ouellette ML, Beller GA, Loffler AI, Workman VK, Bourque JM. Appropriate Referrals of Angiography Despite High Prevalence of Normal Coronary Arteries or Nonobstructive CAD. J Am Coll Cardiol. 2017 May 30;69(21):2673-2675. doi: 10.1016/j.jacc.2017.03.565. No abstract available.
• Zhang F, Wagner AK, Ross-Degnan D. Simulation-based power calculation for designing interrupted time series analyses of health policy interventions. J Clin Epidemiol. 2011 Nov;64(11):1252-61. doi: 10.1016/j.jclinepi.2011.02.007.

Study record dates

Study Major Dates

• Study Start (Actual): July 9, 2018
• Primary Completion (Actual): February 28, 2020
• Study Completion (Actual): March 1, 2022

Study Registration Dates

• First Submitted: May 30, 2018
• First Submitted That Met QC Criteria: May 30, 2018
• First Posted (Actual): June 12, 2018

Study Record Updates

• Last Update Posted (Actual): March 16, 2022
• Last Update Submitted That Met QC Criteria: March 14, 2022
• Last Verified: March 1, 2022

More Information

Terms related to this study

• Keywords: Angiogram, Coronary Computed Tomographic Angiography
• Additional Relevant MeSH Terms: Myocardial Ischemia; Heart Diseases; Cardiovascular Diseases; Vascular Diseases; Arteriosclerosis; Arterial Occlusive Diseases; Coronary Disease; Coronary Artery Disease
• Other Study ID Numbers: 4697

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No