Original Research ArticlePrevalence of myocardial bridging detected with 64-slice multidetector coronary computed tomography angiography in asymptomatic adults
Introduction
The coronary arteries are normally located on the epicardial surfaces of the heart, surrounded by epicardial fat. Myocardial bridging, first described by Reyman1 in 1737, is a congenital condition in which a segment of an epicardial artery has an intramural course within the myocardium. It is typically confined to a single vessel, usually the mid left anterior descending (LAD) artery. The reported frequency at autopsy ranges from 5% to 86%.2, 3, 4, 5, 6, 7, 8, 9, 10, 11 Myocardial bridging is usually asymptomatic and is traditionally considered to be a normal variant or benign coronary anomaly. However, clinical interest has been triggered by the observation that myocardial bridging may be a contributory factor in the development of myocardial ischemia, angina pectoris, myocardial infarction, arrhythmias, and even sudden death.12, 13, 14, 15, 16, 17, 18, 19, 20 Those studies suggest that coronary compression by the myocardial bridge at systole could lead to a reduction in blood flow and subsequent ischemia. Furthermore, myocardial bridging may pose a technical challenge during coronary bypass surgery, because intraoperative echocardiography may be necessary to expose the intramuscular coronary artery.5, 6, 7, 21, 22 Although conventional angiography is recognized as the reference standard examination for the diagnosis of myocardial bridging, its detection rate is <5%, which is significantly lower than that of autopsy studies.2, 3 Detection has improved with the application of newer, more sensitive imaging techniques, such has intravascular ultrasound (IVUS), intracoronary Doppler (ICD) ultrasound, and multidetector computed tomography (MDCT).2, 3, 8, 9
The aim of the present study was to evaluate the prevalence of myocardial bridging and the ability of 64-slice coronary computed tomography angiography (CCTA) to identify myocardial bridging in asymptomatic adults. To the best of our knowledge, this is the first report in the English literature for the prevalence of myocardial bridging in asymptomatic adults using 64-slice MDCT.
Section snippets
Patients and methods
It was a retrospective single-centered analysis that was performed from November 2006 to January 2007 at “Mor” Institute for Cardiovascular Imaging in Bnei Brak, Israel. The study group consisted of 169 consecutive subjects, 132 men and 37 women, who underwent CCTA, ages ranged from 38 to 75 years (mean ± SD, 53.8 ± 7.9 years). All patients were asymptomatic before the examination and were self-referred. Exclusion criteria were allergy to contrast medium, irregular heart rate, and impaired
Results
Images appropriate for evaluation were obtained for 165 subjects. The other 4 subjects were excluded because of motion artifacts of arrhythmia or breathing. The demographic characteristics and cardiovascular risk factors of the 165 participants are shown in Table 1.
Myocardial bridges were found in 28 subjects (17%), with a higher prevalence in men (n = 25; 89.2%). Twenty-one subjects (75%) had 1 bridge and 7 subjects (25%) had 2 bridges, for a total of 35 myocardial bridges. Twenty-one bridges
Discussion
The current imaging standard of reference for the diagnosis of myocardial bridging is conventional coronary angiography, which shows the milking effect and step-down/step-up phenomenon induced by systolic compression of the tunneled segment.
In the present study, we used 64-slice MDCT to evaluate the presence and anatomical characteristics of myocardial bridging in 165 consecutive asymptomatic adults with ≥1 clinical risk factors for atherosclerosis. The incidence of myocardial bridging in our
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Coronary plaque burden of the left anterior descending artery in patients with or without myocardial bridge: A case-control study based on coronary CT-angiography
2021, International Journal of CardiologyCitation Excerpt :On average, MBs can be detected in about one-fourth of the adult population [3], however the prevalence varies depending on the diagnostic modality applied [4]. Using coronary CTA, the prevalence rate of MB varies between 5% and 58% in different cohorts [2,5–7] while it was 17% among asymptomatic adults [8]. Both MB and coronary plaque burden can reliably be investigated by coronary CTA as this method provides accurate visualization of the course of coronary arteries in the epicardial fat and within the myocardial wall [9].
Myocardial bridging on coronary cta: An innocent bystander or a culprit in myocardial infarction?
2012, Journal of Cardiovascular Computed TomographyLeft anterior descending coronary artery myocardial bridging by multislice computed tomography: Correlation with clinical findings
2010, European Journal of RadiologyCitation Excerpt :The prevalence of LAD myocardial bridging by MSCT in our study was with 23% about 10–20 folds higher compared invasive angiography (0.5–2.5%) [1], and was similar to recently published data reporting 26% and 30.5% detection rates [15,16]. The highest prevalence of LAD myocardial bridges by MSCT with 44% (including patients with significant stenosis) was recently reported by Lubarsky et al. [17], but another study found only 17% LAD bridges in asymptomatic patients [24]. The lower prevalence of myocardial bridges identified on invasive angiography compared to MSCT may be related to the fact that the pathognomic “milking-phenomenon” is an indirect diagnostic criterion because invasive angiography does not allow direct visualization of the myocardium.
Myocardial Bridging, a Common Anatomical Variant Rather Than a Congenital Anomaly
2008, Seminars in Ultrasound, CT and MRICitation Excerpt :In addition, only few reports in the cardiac surgery literature have suggested the presence of an intracavitary subtype with an estimated prevalence of 0.2 to 0.3%.25 In the past 2 years, several studies have evaluated the prevalence of myocardial bridging using MDCT.11-15,23 In most series the prevalence is similar to autopsy studies ranging between 3.5 and 39% (Table 1).
Multidetector-row computed tomography is a powerful tool in detection of myocardial bridges but clinical significance remains uncertain
2007, Journal of Cardiovascular Computed Tomography
Conflict of interest: The authors report no conflicts of interest.