Prevalence Of Myocardial Bridging Research Articles

Concurrent Myocardial Bridging and Coronary Artery Disease: A Study of an Iranian Population

Background: Myocardial bridging (MB) has been associated with acute coronary syndrome, ischemia, arrhythmia, and even sudden death. This study investigated the prevalence of MB and its complications and manifestations. Methods: This cross-sectional study was conducted on symptomatic coronary patients who underwent angiography between March 2022 and March 2023 at Afshar or Shahid Sadoughi hospitals in Yazd, Iran. The angiographic reports of all patients were evaluated. Cases with MB were selected, and their angiographic films were assessed by an interventional cardiologist for diagnostic accuracy. Baseline, radiological, and clinical characteristics were also evaluated. Data were collected and analyzed using SPSS, version 20.0. The dependent variable was stratified based on independent variables using the χ2 test. Results: Out of 3750 symptomatic patients, 165 (4.4%) were diagnosed with MB. Among these, 111 (67.3%) were male, and the mean age was 56.87±10.06 years. A total of 152 patients had MB in the left anterior descending artery, representing the highest occurrence proportion at 92.1%. The most common types of coronary artery disease (CAD) diagnosed included mono-vessel disease and slow flow, accounting for 35.1% and 25.8%, respectively. There was no significant frequency distribution of CAD co-occurrence based on baseline and radiological features (P>0.050). Conclusion: This study provides valuable insights into the prevalence of MB in Iran and its co-occurrence with CAD. While some findings align with previous research, certain discrepancies warrant further investigation.

Intramyocardial and intra-atrial courses in the right coronary artery: prevalence and characteristics.

We aimed to determine the prevalence and radiological characteristics of myocardial bridging (MB) and intra-atrial course anomaly (IARCA), which are rare course variations of the right coronary artery (RCA), in the adult patient population. Radiological images of cases over the age of 18 who underwent coronary CT angiography (CTA) examination in our clinic were scanned from the archives retrospectively, and cases with MB of the RCA and IARCA detection were included in the study. The number, age and gender distribution of the cases, whether there were any other accompanying vascular anomalies, whether there was atherosclerosis in the coronary arteries (calculation of Agatston total calcium score, calculation of atherosclerotic stenosis as a percentage, if any) were evaluated. The prevalence of MB in the RCA was 2.06%, and the prevalence of IARCA was 0.44%. In one case, both anomalies were detected together. The average MB segment length in RCA was 21.9mm, and the average IARCA segment length was 37.9mm. There was no atherosclerotic disease in the RCA segment where anomaly was detected. Recognition of rare course anomalies of RCA before treatment procedures such as ablation and surgery is important to prevent complications that may have potentially fatal consequences.

A 20-Year Autopsy Study of Myocardial Bridging Among Sudden Deaths

Myocardial bridging (MB) is a condition, where the cardiac muscle overlies the intramyocardial segment of the major epicardial coronary artery. This study aims to analyse the demographics and anatomical characteristics of MB within a pool of 2093 sudden cardiac-related death cases examined at the Forensic Unit of Universiti Kebangsaan Malaysia Medical Centre between 2000 and 2019. In this cross-sectional study, postmortem data collected were gender, racial affiliations, MB anatomical properties, and association with cardiac pathologies entered into the statistical software SPSS version 25 for analysis. The prevalence of MB was 12.9%. It was commoner in males (91.5%). MB was predominant between age 21-40 years old (50.2%). Chinese race showed the highest number of recorded MB cases (24.3%) among local races. MB was mostly found in left anterior descending (LAD) artery (98.2%), with the commonest length of 11-20mm (44.6%), depth of 1-5mm (49.8%), and distance from the ostium of 21-40mm (54.0%). The prevalence of isolated MB (43.2%) was nearly comparable to that of MB with cardiac pathologies (56.8%). MB was mostly associated with atherosclerosis (50.1%) and atheroma formation was mostly proximal to MB (78.3%). MB is a common occurrence and commonly found in the LAD as a single entity. It has a higher preponderance in the male gender among the adult population. In conclusion, the findings not only contribute to a deeper understanding of MB but also hold potential implications for identifying and managing risks related to sudden cardiac-related deaths. It is a pathological condition at a certain length and depth whether it exists as an isolated entity or associated with cardiac pathologies. Atherosclerosis tends to form proximal to MB and might pose a risk for myocardial infarction.

Myocardial Bridging in Patients Undergoing Coronary Angiography for Coronary Artery Disease.

Introduction Myocardial bridge is a rare, benign, normal anatomical variant of the coronary artery that puts the patient at risk for significant cardiac symptoms, resulting in myocardial ischemia, arrhythmia, and sudden cardiac death. The aim of the study was to assess the prevalence and characteristics of myocardial bridging (MB) in patients with chest pain undergoing coronary angiography. Methodology A total of 1301 patients presenting with chest pain suggestive of acute coronary syndrome with associated non-invasive supportive cardiac evaluation were subjected to coronary angiography by Philips Allura Xper FD10 Cath Lab (Philips Healthcare, Andover, MA)and evaluated. Results Out of 1301 patients, the mean age was 54.70 ± 11.41 years with a male-to-female ratio of 1.9:1. Tobacco use and diabetes mellitus were the most common associated risk factors (49% and 44%, respectively). MBwas seen in 51 patients, making the prevalence 3.9%, with male predominance over females in the ratio of 3.9:1. The most common clinical presentation was unstable angina (UA) (n = 22, 43.1%), followed by stable angina (SA) (n = 11, 21.6%), non-ST-elevation myocardial infarction (NSTEMI) (n = 10, 19.6%), and ST-elevation myocardial infarction (STEMI) (n = 8, 15.7%). Myocardial bridgeswere more common among patients with stable coronary artery disease. The left anterior descending artery (n = 51, 3.9%) was involved in all the cases and the middle segment was affected in all patients with MB.Among patients with myocardial bridge, 26 patients (51%) had atherosclerosis and 25 patients had a normal artery. Among patients with myocardial bridge with atherosclerosis, 17 patients (65%) had atherosclerosis in the same artery in which the myocardial bridge was present. Among patients with myocardial bridge with atherosclerosis, nine patients (52%) had atherosclerosis proximal to the bridge, three patients (17%) had atherosclerosis distal to the bridge, and five patients (31%) had atherosclerosis both proximal and distal to the bridge. Conclusion The prevalence of MB in the Indian population is significantly lower than in the Western populations, and it is significantly higher in the male population with patients diagnosed as normal coronaries on coronary angiography.

High Prevalence of Myocardial Bridging Detected in an Indonesian Population Using Multi-Detector Computed Tomography.

Background and Objectives: Myocardial bridging (MB) is still not yet considered a significant finding in Indonesia both radiographically and clinically. Hence, this article aims to assess the prevalence of MB using multi-detector computed tomography (MDCT) and look at factors contributing to stenosis amongst patients with MB. Materials and Methods: This study is cross-sectional in a single centre, with consecutive sampling, looking at all patients who underwent a multi-detector computed tomography (MDCT) scan from February 2021 until February 2023. GraphPad Prism version 9.0.0 for Windows (GraphPad Software, Boston, MA, USA) was used to analyse the results. Results: There are 1029 patients with an MB, yielding a prevalence of 44.3% (95%CI 42.3-46.4). The left anterior descending vessel is the most commonly implicated, with 99.6%. Among those with stenosis, the middle portion of the bridging vessel is the most common site of stenosis (n = 269), followed by the proximal portion (n = 237). The severity of stenosis is more often moderate, with 30-50% (n = 238). Females (odds ratio [OR] of 1.8, 95%CI 1.4-2.3; p-value < 0.0001), older age (t-value 5.6, p-value < 0.0001), symptomatic patients (OR 1.4, 95% CI 1.1-1.9; p-value = 0.013), and higher mean coronary artery calcium score (t-value 11.3, p-value < 0.0001) are more likely to have stenosis. The degree of stenosis is significantly higher in the proximal stenosis group than in the middle stenosis group (t-value 27, p-value < 0.0001). Conclusions: Our research demonstrates that MB may prevent atheromatosis of the coronary segment distal to the MB and predispose the development of atherosclerosis in the section proximal to the bridge.

Prevalence of myocardial bridges in the Mexican population: A morphometric and histological analysis

Myocardial bridge (MB) is described as an abnormal band of myocardium covering a variable portion of any coronary artery. The current study explores the presence of MB throughout the coronary arterial system and provides a morphometric description through instrumented dissection of a sample of 100 human hearts. The study shows a higher prevalence of MB in the Mexican population than in previous reports. In the total sample (n=100), MB was identified in 96% of it. A total of 421 MBs were observed, with a mean of 4.38mm (±0.28) per dissected heart. The most frequently affected vessel is the anterior interventricular artery where a total of 52 MBs were found, of the total sample studied. The high prevalence of MB among Mexican patients could be the result of a genetic association for this population or the neoformation of MB after birth due to lifestyle-associated factors. Further studies are required to better understand the high prevalence of MB among Mexican subjects.

Use of Intravascular Ultrasound and Coronary Angiography to Measure the Prevalence of Myocardial Bridge in Heart Transplant Patients

Myocardial bridge (MB) detection rates vary across methods and most studies that have assessed MB include symptomatic patients. Intravascular ultrasound (IVUS) is a sensitive tool for MB detection and donor hearts may serve as a surrogate measure of asymptomatic patients. We used IVUS and coronary angiography to measure MB prevalence in heart transplant patients during routine follow-up invasive coronary assessments. This was a retrospective, single-center study of heart transplant patients who received follow-up coronary assessments at the University of Chicago Heart and Vascular Center between December 2014 and December 2021. A single experienced interventional cardiologist assessed incidental findings of MB in IVUS and coronary angiography. Detection rates were compared with meta-analysis-reported prevalence. Of 129 patients, IVUS-detected MB in 87 patients (67.4%), whereas coronary angiography detected 41 (31.8%). All MB found by coronary angiography were detected by IVUS. Some level of cardiac allograft vasculopathy was found in 92 patients (71.3%). Our IVUS-detected MB prevalence was greater than meta-analysis-reported pooled prevalence across all methods: autopsy, computed tomography angiography, and coronary angiography (67.4% [95% confidence interval [CI] 59.4 to 75.5] vs 42% [95% CI 30 to 55]; 22% [95% CI 18 to 25]; 6% [95% CI 5 to 8], p≤0.005). The difference between our observed IVUS-detected MB prevalence and meta-analysis autopsy reported MB prevalence was 1.25 (95% CI 1.11 to 1.40). In conclusion, the high prevalence of MB recorded in donor hearts emphasizes the need to further investigate the causes of chest pain in patients who are found to have MB.

Incidence and Morphological Study of Myocardial Bridge in the State of Ceará: A Cadaveric Study.

Myocardial bridges (MB) are anatomical anomalies with possible clinical repercussions; hence, their understanding deserves attention. To determinate the prevalence and characterize MB in human hearts from the state of Ceará. Methods: Fifty hearts of adult human cadavers from the Medicine School of Federal University of Ceará, Brazil. The hearts were dissected to identify MBs that pass over part of the coronary artery. The segment of the artery (proximal, middle, and distal) with a bridge was identified. The external diameter of the artery at the proximal and distal points of the MB was measured. The length and thickness of the MB were also measured with an electronic caliper. The muscle index (MMI) of the MB was calculated as the product of length and thickness expressed in millimeters. The significance level adopted in the statistical analysis was 5%. MB was confirmed in 40% of sample. Approximately one third of the sample had only 1 MB. MB was most frequently found over the anterior interventricular branch of the left coronary artery (59.25%, p=0.02), and its prevalence in other branches was much lower (22.23%). The most affected segments of arteries were the superior (44.44%) and medium (40.74%). The mean diameter of arteries proximal to the MB was 2.38±0.97mm (range=0.78-5.15mm), and the diameter distal to the MB was 1.71±0.75mm (range=0.42-3.58mm). The length was measured as mean=8.55±5.27mm, while the mean thickness was 0.89±0.33mm. A high prevalence of MB is more likely to affect the left coronary artery system with larger MMI than other affected branches.

Clinical profile of patients having myocardial bridge on coronary angiography at tertiary care hospital in Rajasthan

ABSTRACT Introduction: Myocardial bridge (MB) is usually defined as the segment of the coronary artery (epicardial) which passes intramurally. In the early days, it was not having any clinical importance, but later studies showed the presence of it in the left anterior descending (LAD) artery can be associated with myocardial infarction and cardiac death suddenly. Material and Methods: The aim of this study was mostly to assess the profile of patients with the MB on coronary angiography and to evaluate its association with atherosclerotic disease in the coronary artery at a tertiary care hospital in Rajasthan. In this study, evaluation was done (retrospectively) of the angiographic reports of the patients, and the prevalence of MB was seen totally, individually, or in combination with LAD, left circumflex, and right coronary artery. Results: Out of all 140 patients, 125 (89%) were males, and 15 (11%) were females. Among 140, the mean age of the patients having MB was 55.51 years. Out of 140 patients, 46% (65 patients) had diabetes, 41% (58 patients) had hypertension, and 42% (59 patients) were found to be smoker. Conclusion: The prevalence of MB in our study is similar to what is reported in the literature. The most common location of the MB was the mid-LAD segment.

Prevalence of Myocardial Bridging in Angiography Study.

Myocardial bridging is a congenital anomaly in which a segment of epicardial coronary artery takes an intramyocardial course, the systolic compression of which could be asymptomatic or may lead to major hemodynamic changes such as myocardial ischemia, arrhythmias or sudden cardiac death. The prevalence is highly variable depending upon different investigational modalities to diagnose it. Here we have aimed to study the prevalence through invasive coronary angiography. This retrospective study was carried out at Manmohan Cardiothoracic Vascular and Transplant center, Kathmandu, Nepal. The invasive coronary angiography of 5096 patients were studied from March 2018 to April 2021 done for various indications. Among all the patients, the myocardial bridging was identified in 257 (5.04%) patients. About 177 (68.9%) were males and 80 (31.1%) were females. The mean age of the patients having myocardial bridging was 54.52 ± 10.31years. Diabetes mellitus was found in 33(12.8%) and hypertension was found in 77(29.9%) patients with myocardial bridging. Stable angina (29.2%) was the most common clinical presentation. Treadmill test was positive in about 70 (27.2%) patients. Majority of patients had myocardial bridge in left anterior descending artery alone (89.9%) and located mostly in mid-part (74.9%). The myocardial bridging is not an uncommon finding on invasive coronary angiography in middle aged people who present with typical angina.

Myocardial bridge over coronary arteries and myocardial coat lining coronary sinus: clinical implications

Myocardial Bridge (MB) on the coronary artery and myocardial coat (MC) on the cardiac veins are usually detected in angiography and cadaveric dissection. Left anterior descending branch (LAD) of the left coronary artery is the most frequent site of MB. Rarely MB is also seen over the right coronary arterial branches. MB has proven association with ischemic heart disease and other critical cardiac consequences like myocardial infarction (MI) (Alegria et al., 2000; Soran et al., 2000). MC, on the other hand has not gained enough attention in previous studies. Large MB can be readily identified in angiograms, but minutes MB can be picked up by newer imaging studies like multidetector computed tomography (MDCT) and optical coherence tomography (OCT) scan (Tiryakioglu and Aliyu, 2020). Cadaveric dissection, however, holds its unique place in direct visualization and studying the macro and micro-anatomical characteristics. To study the prevalence and anatomical attributes of MB and MC in Indian population, ten adult cadaveric hearts (6 male and 4 female) were dissected as part of a routine undergraduate teaching at the Anatomy Department, All India Institute of Medical Sciences, New Delhi, India. MB over the coronary artery and MC over the cardiac vein were identified. Data pertaining to the MB and MC dimensions were measured with a digital vernier calliper. Histology of the MC was carried out to confirm its presence and observe the cytoarchitecture pattern. Relevant gross macroscopic and microscopic images were photographed and photomicrographed. 20% of the dissected cadavers revealed MB involving LAD in first heart while LAD and RCA both in second heart with lengths 5 mm, 18 mm and 2 mm respectively. MC was noted over coronary sinus and proximal few millimeters of great and middle cardiac veins. Histological examination revealed cardiac striated muscle in MC with typical cyto- architecture. The mean myocardial muscle index (MMI) of MBs ranged from 1.6 to 21.6. The present study highlights 20% prevalence of MBs in Indian population involving both right and left coronary artery. 10% of the subjects had histologically confirmed MC over cardiac veins. MC over the coronary sinus and other cardiac veins need more elaborate explorative studies to quantify the anatomic properties and to examine the possible association with cardiovascular disease. Nevertheless, anatomic attributes should be kept in mind to better appreciate MI in evolution and MI at evaluation in a case with MB.

Myocardial Bridging is Significantly Related to Myocardial Infarction with Non-Obstructive Coronary Artery Disease

Myocardial infarction with non obstructive coronary arteries (MINOCA) is a complex working diagnosis including coronary and non-coronary causes, like spontaneous coronary dissection, coronary thrombosis or embolism, myocarditis and cardiomyopathy. The prevalence of MINOCA is increasing, but the underlying etiology remains undetermined in more than 10% of cases. Hypotheses on the potential contributing role of myocardial bridge (MB) in takotsubo cardiomyopathy and coronary artery spasm (CAS) have been raised. We aim to investigate the relationship between MB and MINOCA. An observational retrospective study was conducted on 15,036 patients who had been referred for coronary angiography and who fulfilled the Definition of Myocardial Infarction. The study population was divided into STEMI and Non-STEMI patients, from which we defined two main groups: the MINOCA group and the coronary artery disease (CAD) group. The prevalence of MB was calculated in each group ( Fig. 1 ). The distribution of angiographic MB among the groups was significantly greater in the MINOCA group (2.9% vs. 0.8%, P < 0.001). MINOCA accounted for 14.5% of spontaneous myocardial infarctions, and the clinical presentation was frequently NSTEMI rather than STEMI (84.3% vs. 15.7%, P < 0.001). Adjusted multivariate analyses showed a positive association between MB and MINOCA [OR = 3.28, 95% CI (2.34; 4.61) P < 0.001]. Cardiovascular risk factors were less common in the MINOCA population, which was younger and more often female. The main finding of the present study was that MB is an independent predictor for MINOCA, increasing the corresponding risk by threefold. Because MB prevalence differed significantly between the controls (CAD group) and in the MINOCA group, which was positively correlated to MB, it seems likely that MB would be a potential cause of MINOCA. Future prospective studies are necessary to highlight the physiologic significance of MB in some MINOCA patients.

Myocardial bridging in the course of coronary arteries and its clinical significance

Background: Sudden death in young adults in absence of any risk factor related to coronary arterial disease has been reported. It could be because of some unrecognized congenital coronary artery anomalies like myocardial bridging. The clinician should keep myocardial bridging as a differential diagnosis in cases of sudden death in young individuals having no risk factors of coronary artery diseases.&#x0D; Aims and Objective: The present study was conducted to know the prevalence of myocardial bridge and percentage of distribution of myocardial bridges in the course of different coronary arteries of cadaveric hearts.&#x0D; Material and Methods: The study was conducted in the department of Anatomy, IMS, BHU Varanasi. Total numbers of 49 formalin preserved hearts were taken for the study. The hearts were meticulously dissected to see the distribution and location of myocardial bridge. Coronary arteries with myocardial bridge were photographed and data was statistically analyzed.Out of 49 hearts, 26(53.06%) showed myocardial bridging. Total numbers of bridges were found to be 34 in number. Among the 26 myocardial bridged hearts 8 hearts (30.76%) showed double myocardial bridges and 18 hearts (69.23%) showed single myocardial bridges. In hearts with double myocardial bridging, 5 of them showed myocardial bridging in the territory of both anterior interventricular artery (AIVA) and posterior interventricular artery (PIVA) and 3 showed bridging in the territory of anterior interventricular artery and its diagonal branch. Among the18 single myocardial bridging 16 were in the course of anterior interventricular artery and two showed myocardial bridging in one of the diagonal branch of AIVA. There were 24 myocardial bridges in the course of AIVA, 16 as a part of single myocardial bridged hearts and 8 as a part of double myocardial bridged heart with the percentage of distribution were 2 (8.33%)in the proximal 1/3rd,18(75%)were in middle 1/3rd and 4(16.66%) were in distal 1/3rd.&#x0D; Conclusion: Due to the presence of high percentage of reported myocardial bridges in cadaveric hearts, the clinicians should always screen the young individuals and athletes having myocardial ischemia for the myocardial bridges along with other etiological factors.

Myocardial bridges (tunnel coronary arteries) – from understanding of the pathophysiology to the treatment strategy

Myocardial bridges (MB) are the most common congenital coronary anomaly which are characterized by the passage of a segment of the coronary artery in the thickness, but not on the surface of the myocardium as usually. The proximal segment of the left anterior descending artery (LAD) is the most commonly involved vessel in MB. The prevalence of MB is less than 5% when assessed by coronary angiography, but this finding is much more common at autopsy and can occur in almost 30% - 80% of adults. MB is usually a benign condition and often accidental detection in coronary angiography, but under certain conditions can also lead to arrhythmia, acute coronary syndromes, ischemia or myocardial infarction, and even to sudden cardiac death. The article presents brief data on the prevalence, clinic, pathophysiology, diagnosis, treatment of patients with myocardial bridges.

ISOLATED MYOCARDIAL BRIDGING: A POTENTIAL CAUSE OF SUDDEN CARDIAC DEATH IN THAILAND

Introduction. The clinical significance of myocardial bridging (MB) as a potential cause of death has been debated. There is inconsistency in prevalence reports of MB as a cause of death in sudden cardiac death (SCD). We aimed to identify the prevalence of MB as a potential cause of SCD in non-ischemic heart disease (non-IHD) in Asian population. Methods. The SCD autopsy reports from Bangkok, Thailand between January 2012 and June 2014 were included. External causes, drug toxicity, and inconclusive autopsies were excluded. Conventional risk factors were recorded and compared between MB and non-MB. Results. Among 1,152 autopsy reports, 138 cases (85.5% male) were considered as SCD. 111 cases (80.4%) were caused by ischemic heart disease (IHD) whereas 27 cases (19.6%) were not (non-IHD). In IHD, the causes of death were coronary atherosclerosis, acute myocardial infarction, and old myocardial infarction (41.4, 34.2, and 24.3%). In non-IHD, MB was the most common pathological finding of SCD, followed by isolated left ventricular hypertrophy, hypertrophic cardiomyopathy, and myocarditis (29.6%, 25.9%, 22.2% and 14.8%). There were more males in both groups (MB [87.5%], non-MB [85.4%]). Mean (SD) heart weight of MB was lower than non-MB, [345.0(49.6) vs. 444.0(108.6) g, p=0.012]. There was no difference in mean age and body mass index. Conclusions. Our study suggested that MB might be a potential cause of SCD in non-IHD Asian population and highlights the mortality in asymptomatic MB patients.

Study of Prevalence, Risk Factors and Angiographic Profile of Patients with Myocardial Bridges in a Tertiary Care Hospital, Dhaka, Bangladesh

Background: Band of Myocardial tissue overlying a segment of an epicardial coronary artery is termed myocardial bridge (MB). The aim of this study was to identify the prevalence, risk factors and angiographic profile of patients with myocardial bridge in a tertiary care hospital, Dhaka, Bangladesh. Materials and Methods: This retrospective observational study included a total of 1480 patients with suspected coronary artery disease admitted to Enam Medical College and Hospital, Savar, Dhaka, Bangladesh for coronary angiography between April 2016 to June 20019 of them 43 cases were found to have myocardial bridge. Coronary compression was defined as a maximum systolic luminal compression ≥50%. In this population, 43 patients had systolic luminal compression ≥50%, and all 43 patients were selected for the study to determine the prevalence and risk factors of MB and recorded coronary angiogram was reviewed to see the angiographic location of MB, length of MB and number of vessels involved. Results: In this study incidence of MB was 2.9%. The risk factors associated with MB hypertension were 33 (76.74%), diabetes mellitus 28 (65.11%), hyperlipidaemia 18 (41.86%), family history of CAD 15 (34.88%), smoking history 22 (51.16%). Located of MB in LAD were 34 (79.06%), LCX 07 (16.27%) and RCA 02 (4.65%). The MB were in single vessel 38 (88.37%) and double vessels 05 (11.62%). MBs with atherosclerotic stenosis in LAD were 18 (41.86%), LCX 02 (4.65%), RCA 01 (2.32%) and severity of MB stenosis were in LAD 50 -70% were 27 (62.79%), >70% were 07 (16.27%), LCX 50-70% were 06 (13.95%) and >70% was 01 (2.32%) and RCA 50-70% was 02 (4.65%). The length of MBs segment <10 mm were 06 (13.95%), 10-20 mm were 25 (58.19%) and >20 mm were 12 (27.90%). Conclusion: In this study the prevalence of MB was 2.91%, commonly presented with chronic stable angina. The most risk factors of myocardial bridges were hypertension, diabetes mellitus, hyperlipidaemia, family history and smoking history. In coronary angiography most of the patient of MB was present in association of acute coronary syndrome with documented coronary artery disease and was mainly located in LAD mid segment and the length of MB was mostly 10-20 mm. Further large numbers of case are needed to validate the result of the study.

Prevalence of myocardial bridge in angiographic population-A study from rural part of western India.

Introduction:Intramural course of coronary artery is known as myocardial bridge (MB). Its prevalence is highly variable. Very few studies have been conducted in India, mostly from southern state and that too covering urban population. There are no studies from western India. In this study we aimed to estimate the prevalence of MB in coronary angiogram from rural part of western India.Methods and Results:A total of 4,438 patients underwent coronary angiography for various indications during the study period of 69 months. Mean age of the study population was 53.6 ± 11.2 years. MB was found in 212 (4.77%) of patients, predominantly in males. Unstable angina was the most common presentation among males (28.7%), whereas chronic stable angina was being the most common presentation among females (22.6%). Majority of MBs were seen in left anterior descending artery in its mid part (61%). Mean diameter compression of the affected segment was 32.6% ± 11.8%, with no significant difference seen among males and females or between mid and distal left anterior descending artery.Conclusion:Our study showed the prevalence of MB similar to other Indian studies. Left anterior descending artery was most common artery involved. Mean compression was not statistically significant among either sex.

P1825 Myocardial bridging and coronary artery disease in hypertrophic cardiomyopathy: a matched case control study

Abstract Funding Acknowledgements None. Introduction The etiology of chest pain in hypertrophic cardiomyopathy (HCM) is diverse and includes coronary artery disease (CAD) as well as HCM-specific causes. Myocardial bridging (MB) has been associated with HCM, chest pain, and accelerated atherosclerosis. To investigate differences in the presence of MB and CAD, we compared HCM patients with age-, gender- and CAD pre-test probability (PTP)-matched outpatients presenting with chest pain. Methods We studied 84 HCM patients who underwent cardiac computed tomography and compared these with 168 matched controls (age 54 ± 11 years, 70% men, PTP 12% [5%–32%]). MB, calcium score, plaque morphology and presence and extent of CAD were assessed for each patient. Linear mixed models were used to assess differences between cases and controls. Results Differences between HCM patients and controls are described in the table. In summary, MB was more often seen in HCM patients (50% vs. 25%, p &amp;lt; 0.001), who were also more likely to have &amp;gt;1 segment affected (14% vs. 2%, p &amp;lt; 0.05). In the HCM group, MB was associated with pathogenic mutation status. Calcium score and the presence of obstructive CAD were similar in both groups (9 [0-225] vs. 4 [0-82] and 18% vs. 19%; p &amp;gt; 0.05 for both). Conclusion MB was twice as prevalent in the HCM group. However, in a matched analysis, the prevalence and extent of CAD was equal among patients with and without HCM. These finding illustrate that despite a higher prevalence of MB, the prevalence of CAD is similar between groups, also demonstrating satisfactory performance of pre-test risk prediction in HCM patients. Assessment of CAD by CT HCM group(n = 84) Control group (n = 168) p-value Agatston score 9 [0-225] 4 [0-82] 0.22 No. of pts with score* 0.07 0-399 31 (89%) 149 (91%) &amp;gt;400 8 (11%) 15 (9%) Obstructive CAD 15 (18%) 32 (19%) 0.82 No. of pts with MB 42 (50%) 42 (25%) &amp;lt;0.001 No. of vessels with MB &amp;lt;0.001 1 34 (40%) 39 (23%) 2 8 (10%) 3 (2%) No. of pts with &amp;gt;1 segment with MB 12 (14%) 4 (2%) &amp;lt;0.001 Abbreviations CAD = Coronary artery disease, MB = Myocardial bridging, pts = patients *Only measured in 73/84 HCM patients and in 164/168 control patients

Anatomic variations of coronary arteries: origins, branching patterns, and abnormalities

Abstract Background Anatomic variations in orifices, courses, branching patterns, and abnormalities of coronary arteries could affect blood supply, hemodynamic characteristics, and clinical symptoms, and could be a risk of atherosclerosis. Objectives To investigate the location and number of both coronary orifices in the aortic cusps, branching patterns of left main trunk, dominant pattern of posterior interventricular artery (PIA), prevalence of right posterior diagonal artery (RPDA), myocardial bridge, and other abnormalities. Methods We dissected 95 heart specimens from cadavers of Thai donors without the history of surgery, and the dominant patterns, location and number of orifices in the aortic cusps, branching patterns, origin and number of conal arteries, and occurrence of RPDA were determined. Results Dual aortic origin of the coronary orifice was the most common condition. Anomalous 2 orifices in the left aortic cusp were found in one specimen in which the right coronary artery (RCA) arose from aortic cusp and had an interarterial course. Right dominance and trifurcated form of left main trunk were found more frequently. Most frequently 2 conal arteries were found. RPDA was found in 45% and mostly originated from RCA. The prevalence of myocardial bridge was 62% and located mostly on the anterior interventricular artery (AIA). Conclusions The prevalence of right dominance, RPDA, the atypical origin of RCA from the left sinus, and the prevalence of myocardial bridges was more frequent than reported by others, whereas the dual aortic origin from both cusps and the prevalence of bifurcated left main trunk was less frequent.

Prevalence and clinical presentation of myocardial bridge on the basis of the National Polish Percutaneous Interventions Registry and the Classification of Rare Cardiovascular Diseases.

BACKGROUND A myocardial bridge (MB) is defined as a congenital anomaly, in which a segment of an epicardial coronary artery takes an intramuscular course. AIMS The aim of the study was to evaluate the prevalence of MB in coronary arteries among patients who were diagnosed using coronary angiography. METHODS Data were obtained from the National Polish Percutaneous Interventions Registry for patients hospitalized between January 1, 2014, and December 31, 2016, in invasive cardiology departments in Poland and divided into groups with and without MB. RESULTS The study included 298 558 patients. The non‑MB group comprised 296 133 patients (99.19%; women, 38.01%), while the MB group included 2425 patients (0.81%; women, 39.98%). The most frequent location of MB was the left anterior descending artery (n = 2355; 97.11% of patients). The MB group less often had diabetes (14.68% vs 21.63%), previous stroke (1.61% vs 2.96%), previous myocardial infarction (10.97% vs 21.97%), kidney disease (2.8% vs 5.04%), previous coronary artery bypass graft (1.03% vs 5.64%), previous percutaneous coronary intervention (13.20% vs 25.86%) than the non‑MB group (P <0.0001). The incidence of acute coronary syndromes was lower in the MB group (P <0.0001), while smoking was more common (18.76% vs 16.87%, P <0.01). CONCLUSIONS Patients with MB were younger and had fewer comorbidities and risk factors for atherosclerosis than patients without MB. The condition was more common among patients with stable coronary artery disease. Smoking and female sex appeared to be associated with a more clinically symptomatic presentation of MB.