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Non-invasive estimation of coronary resistance and compliance: Prospective diagnostic study vs. angiography
Byoung-Kwon Lee1, Seog-San Hyeon2, YouSik Hong3
1Cardiovascular Center, Department of Internal Medicine, Gangnam Severance Hospital, College of Medicine, Yonsei University, Seoul, 06273, Republic of Korea.
Insights
A new non-invasive device, Coronyzer, shows promise for early coronary artery disease (CAD) screening. It offers a radiation-free alternative for patients unable to undergo traditional diagnostic tests.
Area of Science:
- Cardiology
- Medical Devices
- Diagnostic Imaging
Background:
- Early identification of coronary artery disease (CAD) is crucial but challenging, especially for patients unsuitable for exercise or contrast-based tests.
- Conventional diagnostic methods may pose risks or be inaccessible to certain patient groups.
Purpose of the Study:
- To evaluate the diagnostic accuracy of the non-invasive Coronyzer (KH-3000) pulse wave-based device for early CAD screening.
- To assess the device's ability to derive resistance and compliance indices for CAD detection.
Main Methods:
- A prospective diagnostic accuracy study involved 94 patients with suspected angina undergoing coronary angiography (CAG).
- A retrospective validation study included 136 patients who underwent CAG and CTCA.
- Diagnostic performance was assessed using predefined thresholds and decision rules (OR/AND) for resistance (R) and compliance (C) indices.
Main Results:
- In the prospective cohort, Coronyzer achieved 81% sensitivity and 89% specificity for CAD detection.
- The validation cohort showed varied performance based on decision rules: OR rule (0.77 sensitivity, 0.41 specificity) and AND rule (0.53 sensitivity, 0.78 specificity).
- Receiver operating characteristic (ROC) analysis indicated moderate overall diagnostic accuracy (AUC = 0.67).
Conclusions:
- Coronyzer demonstrated clinically meaningful performance as a non-invasive tool for CAD screening and risk stratification.
- The device avoids radiation, contrast agents, and exercise, aiding early clinical triage.
- It is particularly beneficial for patients with limitations for conventional diagnostic testing.
Background:
Early identification of coronary artery disease (CAD) remains challenging, particularly in patients who cannot undergo exercise-based or contrast-dependent diagnostic testing. We evaluated a non-invasive pulse wave-based device, Coronyzer (KH-3000), designed to derive resistance and compliance indices for early screening of CAD.
Methods:
A prospective diagnostic accuracy study was conducted in 94 patients with suspected angina who underwent coronary angiography (CAG). Significant CAD was defined as ≥50% diameter stenosis. Diagnostic performance was assessed using pre-specified thresholds for resistance (R) and compliance (C). An independent retrospective validation study was performed in 136 patients who underwent CAG and computed tomography coronary angiography (CTCA). Diagnostic performance was evaluated using predefined OR and AND decision rules (R > 1.24 and/or C < 0.8).
Results:
In the prospective cohort, sensitivity and specificity were 81% and 89%, respectively. In the validation cohort, the OR rule demonstrated high sensitivity (0.77) with lower specificity (0.41), whereas the AND rule showed lower sensitivity (0.53) but high specificity (0.78). Receiver operating characteristic (ROC) analysis demonstrated moderate overall diagnostic accuracy (area under the curve (AUC) = 0.67).
Conclusions:
Coronyzer demonstrated clinically meaningful diagnostic performance as a non-invasive screening and risk stratification tool for coronary artery disease. By avoiding radiation exposure, contrast agents, and exercise requirements, the device may support early clinical triage and referral for further diagnostic evaluation, particularly in patient populations for whom conventional testing is limited.
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