Assessment of Left Ventricular Function in Symptomatic Patients with Myocardial Bridge using Two-Dimensional Strain.
10.4070/kcj.2006.36.9.617
- Author:
Kyoung Im CHO
1
;
Jeong Ho PARK
;
Jong Ryul PARK
;
San KIM
;
Jeong Myung AHN
;
Jin Ho LEE
;
Hye Jung JANG
;
Tae Ik KIM
Author Information
1. Division of Cardiology, Maryknoll General Hospital, Busan, Korea. Kyoungim74@dreamwiz.com
- Publication Type:Original Article
- Keywords:
Echocardiography;
Strains
- MeSH:
Coronary Vessels;
Echocardiography;
Electrocardiography;
Heart;
Humans;
Ischemia;
Myocardial Bridging;
Papillary Muscles;
Relaxation;
Systole;
Ventricular Function, Left*
- From:Korean Circulation Journal
2006;36(9):617-625
- CountryRepublic of Korea
- Language:English
-
Abstract:
BACKGROUND AND OBJECTIVES: We wanted to perform quantitative echocardiographic assessment of myocardial function in the patients with myocardial bridge by measuring 2-dimensional strain with using newly developed software. SUBJECTS AND METHODS: Novel computer software was used for tracking heart tissue on echocardiography, and we conducted an advanced wall-motion analysis for 18 symptomatic patients (mean age: 57.1+/-9.7 years, 10 female) with myocardial bridging of the left anterior descending coronary artery and also 20 age-matched healthy controls. The conventional wall-motion scoring was normal in all the patients, and the software was able to adequately track their heart tissue. RESULTS: The maximal angiographic systolic lumen diameter reduction within the myocardial bridges was 71+/-12.6% at rest, with a persistent diameter reduction of 31.2+/-11.3%. The radial strain and displacement of the anterior segments were more significantly reduced than that of the posterior segments at the level of the papillary muscle (30.9+/-13.8% vs. 51.8+/-17.3% and 4.8+/-0.9 vs. 5.9+/-1.5, respectively, all p<0.05), and this showed a plateau (39% and 33%, respectively) or biphasic (50% and 56%, respectively) pattern. The time from the R wave on electrocardiography to the transition from regional systole to early diastolic lengthening (Tr) was significantly delayed in the patients with myocardial bridge more than that for the controls (497+/-20.4 ms vs. 348+/-12.5 ms, respectively, p<0.05). CONCLUSION: Delayed systolic contraction and diastolic relaxation are important mechanisms that contribute to ischemia in the patients with myocardial bridge. 2-dimensional strain can be used to achieve real-time wall-motion analysis, and it has the potential to improve the identification and functional quantification of myocardial Bridge.
