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07:21
Magnetic Resonance Derived Myocardial Strain Assessment Using Feature Tracking
Published on: February 12, 2011
Differential local spasticity in myocardial bridges
Paolo Angelini1, Carlo Uribe, Pablo Lozano
1Division of Cardiology, Texas Heart Institute at St. Luke's Episcopal Hospital, Houston, Texas 77030, USA. PAngelini@leachmancardiology.com
Texas Heart Institute Journal
|June 22, 2012
Summary
Myocardial bridges can cause coronary artery spasticity, leading to conditions like takotsubo cardiomyopathy and Prinzmetal angina. Acetylcholine challenges help identify and assess this spastic tendency in patients with myocardial bridges.
Area of Science:
- Cardiology
- Vascular Physiology
Background:
- Myocardial bridges are congenital anomalies where a segment of a coronary artery travels through the heart muscle.
- The effect of myocardial bridges on coronary vascular tone and potential for spasticity remains incompletely understood.
Observation:
- Two patients with myocardial bridges presented with distinct clinical scenarios: takotsubo cardiomyopathy and Prinzmetal angina.
- Both patients exhibited reproducible increased spasticity at the myocardial bridge site.
- Acetylcholine challenge testing effectively demonstrated the presence and severity of myocardial bridging and associated spasticity.
Findings:
- Myocardial bridging is associated with abnormal coronary artery spastic tendency.
- The degree of spasticity correlates with baseline functional states and responses to various medications.
- Acetylcholine challenge is a valuable tool for characterizing myocardial bridging-related spasticity.
Implications:
- Understanding the spectrum of spastic conditions related to myocardial bridges can clarify atypical ischemic events.
- This knowledge may guide therapeutic strategies for patients experiencing symptoms attributed to myocardial bridging.
- Further research into coronary vascular tone modulation in myocardial bridging is warranted.
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