Related Experiment Video
Updated: Jul 7, 2026
Surgical Porcine Model of Chronic Myocardial Ischemia Treated by Exosome-laden Collagen Patch and Off-pump Coronary Artery Bypass Graft
Published on: September 15, 2023
Mechanisms involved in symptomatic myocardial bridging: Value of sequential testing for endothelial function, flow
A J C Hazenberg1, G A J Jessurun, R A Tio
1Department of Cardiology, Groningen University Medical Centre Groningen, University of Groningen, Groningen, the Netherlands.
Insights
Sequential invasive testing helps evaluate myocardial bridging, a challenge in patients with chest pain. Dobutamine stress revealed lumen reduction, offering insights into bridging significance.
Area of Science:
- Cardiology
- Cardiovascular Physiology
- Diagnostic Imaging
Background:
- Evaluating the clinical significance of extensive myocardial bridging is challenging.
- Myocardial bridging can cause angina, but its precise mechanism is not always clear.
Purpose of the Study:
- To assess the feasibility and diagnostic value of sequential invasive testing in patients with extensive myocardial bridging.
- To investigate the pathophysiological mechanisms underlying bridging-related angina.
Main Methods:
- Twelve patients with chest pain and proven myocardial bridging underwent sequential invasive testing.
- Assessments included evaluation at rest, intracoronary acetylcholine infusion, coronary flow velocity/reserve measurements, and dobutamine stress testing.
Main Results:
- Sequential testing was feasible in most patients; two experienced vasospasm with acetylcholine and testing was stopped.
- Coronary flow reserve was preserved in all patients (mean 3.3+/-0.6).
- Dobutamine stress demonstrated significant reduction in bridging segment diameter during systole, increasing lumen narrowing.
Conclusions:
- Sequential invasive testing is feasible and can identify endothelial dysfunction or vasospasm in some patients with myocardial bridging.
- Coronary flow reserve remains preserved, but dobutamine stress can reveal dynamic lumen reduction, aiding in understanding clinical significance.
Background:
In patients with extensive myocardial bridging, evaluation of its clinical significance remains a challenge.
Hypothesis:
Sequential invasive testing is feasible and gives more insight into the pathophysiological mechanism of bridging-related angina.
Methods:
Twelve patients with chest pain, proven ischaemia and extensive myocardial bridging were assessed. Myocardial bridging was evaluated at rest, during intracoronary acetylcholine infusion, through coronary flow velocity and flow reserve measurements, and during dobutamine stress.
Results:
The mean length of the bridging segment was 24.9 mm (QCA; range 8.4-48.0 mm). Acetylcholine infusion caused severe vasospasm in two patients. In these two patients anginal symptoms were related to vasospasm and sequential testing was discontinued. In the remaining ten patients sequential testing was continued. Coronary flow reserve was normal in all patients: 3.3+/-0.6. In six patients reliable quantitative measurements could be performed during dobutamine stress. The mean systolic diameter of the bridging segment was 1.6+/-0.4 at baseline and 1.3+/-0.3 during dobutamine stress (mean of differences 0.38 (95% CI 0.1-0.7)). The difference between the diastolic and systolic diameter in the bridging segment increased from 0.3+/-0.2 mm at baseline to 1.0+/-0.5 mm during dobutamine infusion (mean of differences 0.6 (95% CI 0.3 to 0.9)).
Conclusion:
Sequential testing for bridging is feasible and may disclose endothelial dysfunction or spasm as an underlying mechanism in a minority of patients. Coronary flow reserve was preserved. Dobutamine stress unmasked further lumen reduction and may give further insight into the clinical significance of myocardial bridging in individual patients. (Neth Heart J 2008;16:10-5.).
Related Concept Videos
01:30Acute Coronary Syndrome III: Diagnostic Studies
01:23Mitral Stenosis II: Clinical features and Diagnostic Tests
01:29Angina III: Clinical Manifestations and Assessment
01:30Dysrhythmias V: Evaluating Dysrhythmias
01:26Exercise Stress Test
Exercise stress testing, commonly known as a treadmill test, is a noninvasive procedure used to evaluate cardiovascular function and diagnose heart conditions.
Definition
An exercise stress test measures the heart's response to exertion using a treadmill or stationary bicycle. Chest electrodes record the heart's electrical activity through an ECG, and blood pressure is monitored regularly.
Purposes