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Updated: May 17, 2025
Intracoronary Acetylcholine Provocation Testing for Assessment of Coronary Vasomotor Disorders
Published on: August 18, 2016
Scoring System-Based Approach for Positive Intracoronary Acetylcholine Provocation Tests: The Original and Modified
Yoshiyuki Ohnaga1, Yuichi Saito1, Yuichiro Mori2
1Department of Cardiovascular Medicine, Chiba University Hospital, Chiba, Japan.
Insights
The ABCD score predicts vasospastic angina (VSA) positive acetylcholine (ACh) tests. A modified ABCD score demonstrated improved diagnostic accuracy for VSA compared to the original score in this study.
Area of Science:
- Cardiology
- Diagnostic Medicine
Background:
- Intracoronary acetylcholine (ACh) provocation testing is the standard for diagnosing vasospastic angina (VSA) but is underutilized.
- The ABCD score was developed to predict positive ACh test results, aiding VSA diagnosis.
Purpose of the Study:
- To externally validate the diagnostic ability of the original ABCD score.
- To develop a modified ABCD score for improved prediction of VSA.
Main Methods:
- 723 patients undergoing ACh provocation tests for VSA diagnosis were analyzed.
- The original ABCD score was calculated, and a modified score was developed.
- VSA was defined by significant angiographic vasospasm with chest pain or ischemic ECG changes.
Main Results:
- The original ABCD score showed significant predictive value for positive ACh tests.
- A modified ABCD score was developed with better diagnostic ability (AUC 0.65 vs 0.55).
- The modified score was simpler and outperformed the original score in predicting VSA.
Conclusions:
- The original ABCD score has predictive value for VSA but with modest accuracy.
- The modified ABCD score offers enhanced predictivity for identifying patients with VSA.
Background:
Although intracoronary acetylcholine (ACh) provocation testing is a guideline-recommended invasive standard for the diagnosis of vasospastic angina (VSA), ACh tests are largely underused in clinical practice globally. Recently, the ABCD score, consisting of clinical presentation, myocardial bridge, C-reactive protein, and dyslipidemia, was developed to predict positive ACh test results.
Objectives:
The authors aimed to externally validate the diagnostic ability of the score and attempted to improve the predictivity for identifying patients with VSA.
Methods:
From May 2012 to September 2023, a total of 723 patients undergoing ACh provocation tests for diagnosing VSA were included. The original ABCD score was calculated according to the predefined criteria, and the modified ABCD score was internally developed to improve the diagnostic accuracy. The positive ACh provocation test (ie, VSA) was defined as a significant angiographic vasospasm accompanied by chest pain and/or ischemic electrocardiographic changes.
Results:
Of the 723 patients, 383 (53.0%) had positive ACh provocation test results. The receiver-operating characteristics curve analysis indicated that the original ABCD score was significantly predictive of positive ACh tests. Using best cutoff values on receiver-operating characteristics curve analyses, we developed the modified ABCD score, which was simpler than the original score. The modified rather than original ABCD score had better diagnostic ability for positive ACh test results (area under the curve 0.65 vs 0.55; P < 0.001).
Conclusions:
The original ABCD score was predictive of VSA in this external validation study with modest diagnostic accuracy, while the modified ABCD score achieved better predictivity for identifying patients with VSA.
