Incidence Of Myocardial Bridging Research Articles

Combined Computed Tomography Angiography-Computed Tomography Perfusion in the Identification and Prognostic Assessment of Myocardial Bridging from the CORE320 Study: 5-Year Follow-Up

Our objective is to use computed tomography angiography (CTA) and computed tomography perfusion (CTP) to identify the ischemic significance of myocardial bridging (MB). We also seek to determine the long-term prognostication of MB in the presence or absence of obstructive coronary artery disease (CAD). The CORE320, a prospective, multicenter study including 381 patients with known or suspected CAD clinically referred for invasive coronary angiography who underwent combined (CTA-CTP) and single-photon emission computed tomography before conventional coronary angiography. The incidence of MB was identified in 135 patients (35.4%) with 93.9% identified in the left anterior descending artery. MB were divided as partially encased versus fully encased. There was no difference in ischemia identified between partially encased MB and fully encased MB (37 [40%] vs 25 [35%], p=0.54]. Ischemia was identified at similar rates in partially versus fully encased MB by single-photon emission computed tomography at (8 [9%] vs 8 [11%], p=0.57] and CTP (34 [37%] vs 21 [30%], p=0.33]. There was no difference in the primary outcome of 5-year outcome of combined incidence of myocardial infarction or death. The restricted mean survival time in patients with CTA with <50% stenosis with or without a MB was 4.906 years (95% confidence interval 4.759 to 5.000) and 4.891 years (95% confidence interval 4.718 to 5.000), respectively (p=0.824). Cardiac computed tomography perfusion imaging can assess both anatomic and functional significance of myocardial bridging with diagnostic accuracy similar to current standard imaging. Furthermore, 5-year cardiovascular events were not different with the presence of MB in both obstructive and non-obstructive CAD.

Plaque morphology and distribution in patients with and without myocardial bridge – an intravascular ultrasound study

Background Myocardial bridging (MB) is a common congenital cardiovascular anomaly. There are reported associations of MB with different clinical presentations like effort angina, acute coronary syndromes (ACS) and sudden cardiac death. Acceleration of atherosclerosis in proximal vessel is reported in patients with MB, while bridged segments are reported to be free of atherosclerosis Methods We assessed patients who underwent intravascular ultrasound (IVUS) guided percutaneous intervention (PCI) of left anterior descending (LAD) artery. Plaque characteristics derived from IVUS analysis were compared between those who displayed myocardial bridge versus those who did not harbour the anomaly. Results One hundred and forty-seven (147) patients underwent IVUS guided PCI. Incidence of MB was 44/147 (29.9%). Mean age of patients who had MB {+} was higher (62.1 ± 10.3 vs. 57.8 ± 11.2 (p = .03). 142/147 (96.6%) patients presented with ACS. ST elevation myocardial infarction (STEMI) was the most common presenting diagnosis (110/147 to 74.8%). There were no differences in qualitative plaque characteristics – attenuated plaque, calcification or calcium score between two groups. Plaque burden and length of the lesion in the proximal vessel were not different. Among patients with MB {+}, atheromatous extension to segments underlying the bridge was seen in 31/44 (70.5%) cases. Conclusions In a series of patients who presented with advanced clinical atherosclerosis, plaque characteristics were not different in patients who harboured myocardial bridge vs. those who did not have the anomaly. Atheromatous involvement was seen extending into bridged segment contrary to previous reports.

Analysis of clinical features and the outcome of in-hospital mortality of myocardial infarction with non-obstructive coronary arteries

Objective: To compare the clinical features and the outcome of in-hospital mortality between patients with myocardial infarction with non-obstructive coronary arteries(MINOCA)and myocardial infarction with obstructive coronary artery disease (MI-CAD). Methods: This is a retrospective study. The clinical data of acute myocardial infarction (AMI) patients admitted to Qilu Hospital of Shandong University from January 2017 to May 2021, who underwent coronary angiography, were collected. Patients were divided into MINOCA group and MI-CAD group according to the degree of coronary stenosis (<50% or ≥50%). Baseline clinical characteristics, electrocardiograph during hospitalization, myocardial bridge, length of stay in hospital, discharge medication and the outcome of in-hospital mortality were collected and compared between the two groups. Univariate and multivariate logistic regression analysis was used to screen the related factors of MINOCA and the factors predicting the nosocomial death outcome of patients with AMI. Results: A total of 3 048 AMI patients were enrolled, age was 62 (54, 69) years, 741 (24.3%) patients were women including 165 patients (5.4%) in the MINOCA group and 2 883 patients (94.6%) in the MI-CAD group. Compared with MI-CAD patients, MINOCA patients were younger, had a higher proportion of females and a higher incidence of NSTEMI, and had a lower history of smoking, diabetes, coronary heart disease and myocardial infarction. Baseline inflammatory markers such as neutrophil count, monocyte count, neutrophil count/lymphocyte count (NLR), and monocyte count/high-density lipoprotein count (MHR) were lower, creatinine, N-terminal pro-brain B-type Natriuretic peptides (NT-proBNP), creatine kinase-MB, hypersensitive troponin I, fibrinogen, baseline blood glucose levels were lower, high-density lipoprotein cholesterol was higher, and the incidence of myocardial bridge, arrhythmia, tachycardia and atrial fibrillation was higher (P<0.05). The application rates of calcium antagonists and non-vitamin K antagonists oral anticoagulants were higher in MINOCA group (P<0.05), and there was no statistical difference in hospitalization days and in-hospital death between the two groups (P>0.05). Multiple logistic regression analysis showed that young age, female, non-smoker, no history of coronary heart disease and low MHR were risk factors of MINOCA (P<0.05). MINCOA was not associated with higher in-hospital death (P>0.05). Patients with AMI and a history of coronary heart disease, chronic renal failure, higher baseline blood glucose, higher NLR, and higher D-dimer were risk factors of in-hospital death (P<0.05). Conclusions: Compared with MI-CAD patients, MINOCA patients are younger, more likely to be female and non-smokers and on history of coronary heart disease, and have lower baseline MHR. MINOCA is often associated with myocardial bridge and atrial fibrillation. The incidence of in-hospital death in MINCOA patients is similar as in MI-CAD patients.

Is myocardial bridge more frequently detected on radial access coronary angiography?

BackgroundAlthough the incidence of myocardial bridge (MB) has been defined in different femoral access conventional coronary angiography (FACCA) studies, the frequency of MB on radial access coronary angiography (RACA) is unknown. The aim of this study was to determine the difference in the incidence of MB between patients undergoing RACA and FACCA.MethodA total of 2500 consecutive patients who underwent RACA and a total of 1455 consecutive patients who underwent FACCA were retrospectively investigated to detect the presence of MB. The incidences of the groups were calculated separately and compared. The clinical and angiographic features of the patients with MB were analyzed.ResultsMB was detected at an incidence of 10.2%, in 255/2500 patients who underwent RACA, and 1.8% in 27/1455 patients who underwent FACCA (p < 0.001). In both RACA and FACCA patients, the most involved coronary artery was the left anterior descending artery (LAD) (86.9% and 93.1%) and the mid-segment (84.9% and 88.9%) was the most affected section. Co-involvement of multiple coronary arteries by MB was 7.8% in patients who underwent RACA and 7.4% in patients who underwent FACCA. Coronary artery disease (CAD) was determined in 111 (35.7%) of the coronary arteries with MB, of which 81.9% were proximal to the MB. No significant CAD was detected in any of the vessels of 69.8% (178/255) of the patients who underwent RACA for different clinical indications.ConclusionThese data demonstrated that the incidence of myocardial bridge able to be detected on RACA was much higher than FACCA.

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.

A study to find out the Incidence of Myocardial bridges in the human Cadaveric Hearts.

A study to find out the Incidence of Myocardial bridges in the human Cadaveric Hearts.

PERCENTAGE INCIDENCE, MORPHOLOGY AND MORPHOMETRY OF MYOCARDIAL BRIDGES: A CADAVERIC STUDY

Address for Correspondence: Ms. Sujatha Manupati, Ph.D. Scholar, Department of Anatomy, Sri Venkateswara Medical College, Tirupati, Andhra Pradesh. India. Mobile No.: +919246943011 E-Mail: manupatisujatha@gmail.com *1 Ph.D. Scholar, Department of Anatomy, S.V. Medical College, Tirupati, Andhra Pradesh, India. 2 Professor & Head, Department of Anatomy, S.V. Medical College,Tirupati, Andhra Pradesh, India. 3 Associate professor, Department of Forensic Medicine, RIMS Medical College, Kadapa, Andhra Pradesh, India. 4 Professor & Head, Dept of Anatomy, SVIMS, Sri Padmavathi Medical College for women, Tirupati, Andhra Pradesh India. Introduction: Myocardial bridging is the term used when a segment of major epicardial coronary artery runs intramuscularly under the tunnel formed by fibers of myocardium that bridges instead of it’s normal or routine epicardial path. In the literature there are varying reports on clinical implications of myocardial bridges from protection against atherosclerosis to myocardial ischemia, as well as leading to infarction and sudden cardiac death. Materials and Methods: 150 adult formalin fixed human hearts which were available in the department of Anatomy and Forensic Medicine, S.V.Medical College, Tirupati, Andhra Pradesh, India. These hearts were dissected and observed for the presence, location, type, number and direction of myocardial bridges and their association with coronary dominance. With the help of digital calipers morphometric parameters (length, width& thickness) of myocardial bridges and length of blood vessel underneath the myocardial bridge were measured, noted and photographs were taken. Results: The overall incidence of myocardial bridges was 20.6%( 31/150). Among these 18.6% (28/31) were on left anterior descending (LAD) artery and 2% (03/31) were on posterior interventricular (PIV) artery. The direction of muscle fibers in the bridges were oblique to the direction of the coronary vessels in majority of cases. Length, width and thickness of myocardial bridges were in the range of 12-69.7mm, 3.74-8.6mm and 1.3-3.87mm respectively. Conclusions: Myocardial bridges may be associated with wide range of clinical problems. Contraction of myocardial bridge may results in vascular compression and myocardial ischemia. Knowledge on morphology and morphometric details of myocardial bridges facilitates cardiologists in diagnosis, planning therapeutic strategies and prognostic predictions.

A study to find out the incidence of myocardial bridges in the formalin fixed hearts and its co relates

Background: Myocardial Bridges are structures consisting of cardiac muscle fibers which pass above the coronary arteries and their branches. It is regarded as a common anatomic variant rather than a congenital anomaly Objectives: 1. To find the incidence of myocardial bridges in the formalin fixed hearts. 2. To study its distribution and its correlates in the different coronary arteries. Material & Method: A total of 60 formalin fixed hearts were dissected. All the cadavers hearts were adults hearts. After cleaning hearts were numbered and dissected and Coronary Vessels were then traced from the aortic sinus to their termination by cleaning the epicardium and perivascular fat tissues. The origins and courses of two coronary arteries were thus cleared. Once a myocardial bridge had been identified, it was cleaned properly and numbered. The exact locations from the beginning till the end of myocardial bridges were defined. The length of each bridge as well as its distance from the sinus was measured directly by using thread and measuring scale. Result: Of the total 60 formalin fixed hearts dissected, myocardial bridges were present in 22 hearts(36.7%.). The incidence of myocardial bridges was statistically significantly higher in the left coronary artery (36. 7%) as compared to the right coronary artery. Its clearly shows that incidence of myocardial bridging is highest in anterior interventicular artery(AI) Conclusion: The present study hereby observed that incidence of myocardial bridges are quite common in the human being. They are most commonly observed in the left anterior descending artery and t their branches.

040: Myocardial bridging: comparative analysis of coronary angiography and autopsy results

Myocardial bridge (MB) is congenital myocardial band overriding a portion of a coronary artery, mainly LAD. Incidence on coronary angiography (CA) appears lesser than on autopsy, which can be ethnics-related, while clinically all forms of coronary artery disease (CAD) are reported: from benign arrhytmias up to sudden death. We sought to determine incidence of MBs in the Serbian population along with respective clinical features. Retrospective analysis was carried out in the same population, during the same 1-year time-frame and comprised consecutive: (A) 721 autopsies, with LM studies of the tunneled vessel (TV) wall together with the morphometric analysis of the ventricular myocardium supplied by TV (experimental group) and the ventricular myocardium of the same heart but with a different blood supply (control group); (B) 4510 CA of symptomatic patients were re-assessed for presence of MBs. (A) MBs were described in 6 cases (0.8%): 5 male, all over 70yrs. Only single MB over LAD were found, while all showed: a) TV’ intensive atherosclerotic changes proximal to MB, only focal in the tunneled part; b) intensive interstitial fibroses of the TV-supplied myocardium. (B) MBs were found in 42pts (0.93%): 33 male, aged of 55+11yrs, with single MB over the mid-LAD. 29% were CAD-free, 43% had 1-vessel CAD, 2-v-CAD (24%) and 3-v-CAD (4%). MBs were most frequent in hearts with right coronary dominance (69%). Hypertension and smoking were equally present (69%), dyslipidemia (59%), family history of CAD (48%) and diabetes (21%). Pts presented with stable angina (40%), nonspecific symptoms (14%), unstable angina (7%) and supraventricular arrhythmia (5%), with a history of an anterior wall STEMI vs . NSTEMI in 26% vs . 7%. This first overview of MBs-incidence in Serbia (0.8% on autopsy vs . 0.9% on CA) might underestimate its actual presence, which prompted us to continue prospectively.

Is coronary artery bypass grafting an acceptable alternative to myotomy for the treatment of myocardial bridging?

A best evidence topic in cardiothoracic surgery was written according to a structured protocol. The question addressed was 'Is CABG an effective alternative for the treatment of myocardial bridging?' Altogether, only six papers were identified using the reported search that represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes, and results of these papers are tabulated; these studies reported the outcome of myotomy and coronary artery bypass grafting (CABG) for myocardial bridging. All of these studies were retrospective reports of the results of surgical intervention in patients with myocardial bridging. They showed that the incidence of myocardial bridging was less than 1-1.5% in patients with angina requiring angiography, and 7-9% of these patients had refractory angina despite medical treatment and required surgery. The evidence on the treatment of this congenital condition that mainly affects the middle segment of left anterior descending artery is limited, and there are no treatment guidelines currently available. Stenting of the tunnelled segment has shown high failure rates in approximately half of the cases. Current evidence in the literature suggests that surgery is the mainstay treatment for myocardial bridging. Surgery is performed either as supra-arterial myotomy and de-roofing of the muscle bands on- or off-pump, or as coronary artery bypass grafting of the affected coronary artery beyond the tunnelled segment. Although no mortality was reported with either of these operations, surgical myotomy on deep and extensive myocardial bridges carries the risk of entering the right ventricle, bleeding and aneurysm formation. In addition, in a small percentage of the patients undergoing myotomy, angina recurred. Despite the possibility of competitive flow in the native coronary artery after CABG for myocardial bridging, we did not identify any evidence demonstrating graft occlusion after CABG for myocardial bridging. In conclusion, in extensive and deep myocardial bridgings, CABG may be the treatment of choice that carries low risk, limited complications and excellent symptomatic relief.

Abstract 19012: Impact of Beta-Blocker on Angiographic and Clinical Parameters During Intracoronary Acetylcholine Provocation Test

Background: Beta blockers (BB) are widely used to control hypertension. It is well known that BB may lead to significant vasospasm. However, the impact of chronic administration of BB on clinical and angiographic characteristics during acetylcholine (Ach) provocation test is not clarified yet. Methods: A total 3034 consecutive patients (pts) underwent coronary angiography with Ach provocation test from January 2004 to August 2010 were enrolled for this study. Ach was injected in incremental doses of 20, 50, 100μ g into the left coronary artery. Significant coronary artery spasm (CAS) was defined as focal or diffuse severe transient luminal narrowing (&gt;70%) with/without chest pain or ST-T change on ECG. A total 1394 pts (45.9%) showed positive provocation tests. Among the (+) provocation test pts, we compared the clinical and angiographic characteristics of patients with beta-blocker to those without beta-blocker in pts with myocardial infarction. Results: The baseline clinical and procedural characteristics are well balanced between the two groups. There was no difference in the incidence of myocardial bridges, chest pain, ischemic ECG changes and atrioventricular (AV) block on ECG, incidence of baseline spasm, severe vasospasm, multi-vessel involvements during the Ach provocation test were similar in both groups Conclusion: The use of beta blocker in pts with vasospastic angina was not associated with worse clinical and angiographic parameters during the Ach provocation test. BB may be safely used in pts with vasospastic angina.

Does isolated myocardial bridge really interfere with coronary blood flow?

Myocardial bridge (MB) is defined as a segment of a major epicardial coronary artery the “tunneled artery” that goes intramurally through the myocardium beneath the muscle bridge. Multiple methods have been proposed to assess coronary flow rate among which thrombolysis in acute myocardial infarction frame count was a relatively new semiquantitative method. Our goal was to determine incidence of MB in the patients undergoing coronary angiography in Mansoura Specialized Hospital, Cardiac Catheterization Laboratory, also to investigate the hypothesis that slow coronary flow rate may be linked to angina or angina like symptoms in patients with MB without stenotic lesions in epicardial coronary arteries using TFC. Fifteen patients with MB (group I) were retrospectively collected from Mansoura Specialized Hospital, Cardiac Catheterization Laboratory, we review 3000 cases referred to diagnostic coronary angiography to exclude significant coronary artery disease. Fifteen patients with normal coronary angiography served as control (group II). We review the clinical presentations, risk factors, echocardiographic data for both test and control groups. TFC was calculated using a simple continuous index. The incidence of MB in our study was 0.5%. CTFC in LAD was significantly higher in the patients with MB compared with control. No significant correlation between TFC and echocardiographic parameters. Myocardial bridging must be considered especially in patients at low risk for coronary atherosclerosis but with angina like chest pain or established myocardial ischemia. We suggest that coronary blood flow is decreased in the patients with MB compared with the patients having normal coronary.

Evaluation of Myocardial Bridge With Multidetector Computed Tomography

The myocardial bridge (MB) is an intramural segment of coronary artery that is covered with myocardial tissue. The current diagnostic methods are coronary angiography, intravascular ultrasound and intracoronary Doppler, which are all invasive modalities. In this study, multidetector computed tomography (MDCT) was used to detect and evaluate the anatomical properties of the MB. The 607 patients with suspected or known coronary artery disease underwent 64-slice MDCT. MB was diagnosed when an intramural segment of coronary artery was visualized on axial and multiplanar reconstruction images. The prevalence, length, myocardial thickness, and location were evaluated. Of the 607 patients, 39 (6.42%) had a MB. In 20 patients (52.6%), the MB was located in the mid left anterior descending artery. The length of tunneled artery was a mean 16.3 mm, from 6.9 mm to 30 mm, and the maximum thickness of the myocardial tissue was between 0.5 mm and 3.9 mm, with a mean of 1.8 mm. The length of the MB correlated significantly with thickness (P=0.049). The incidence of MB and its anatomical properties can be evaluated with MDCT, which might be a useful and noninvasive method of detecting this variant. (Circ J 2010; 74: 137 - 141).

Myocardial Bridging

According to postmortem studies, coronary atherosclerosis can be substantial and reach a high prevalence of advanced lesions, including atheroma and fibroatheroma in young adults.1,2 Risk factors associated with coronary atherosclerosis such as dyslipidemia, smoking, diabetes mellitus, and hypertension have been identified. The development of atherosclerosis seems to be related to the magnitude and duration of exposure.3 Although research concentrates on identifying genetic markers in genome-wide association studies, there is still a lack of knowledge about the individual risk of developing coronary atherosclerosis.4 When atherosclerosis presents as acute coronary syndromes, mortality may be high.5 Plaque rupture and erosion have been identified as major underlying pathological-anatomic characteristics,6 but some suspect other mechanisms.7 In this issue of Circulation , Ishikawa et al8 present evidence that myocardial bridging may play a role as a congenital anatomic risk factor for coronary atherosclerosis and myocardial infarction. Article see p 376 Myocardial bridging results when myocardial tissue covers part of the left anterior descending coronary artery, resulting in a tunneled arterial segment, which can be regarded as a congenital variant.9–11 The prevalence is reported to be >50% at autopsy.12 Clinically, the diagnosis of myocardial bridging is established by coronary angiography demonstrating a systolic compression, described as a “milking effect,”13 but it was present in only <5% of cases recently in a large number of Chinese patients.14 When nitroglycerin was used as …

Myocardial Bridging in Taiwan: Depiction by Multidetector Computed Tomography Coronary Angiography

Myocardial bridging (MB) is a condition in which a segment of the major epicardial coronary artery is tunneled within and surrounded by the myocardium. This condition has been linked to severe complications. The aim of this study was to evaluate the incidence of MB in Taiwanese subjects examined with electrocardiogram-gated, 16-slice, multidetector computed tomography (MDCT) coronary angiography, as well as to determine the location, depth, and length of the bridged segments and the concomitant atherosclerosis of MB. From August 2004 to May 2005, 276 consecutive subjects referred to our department for MDCT coronary angiography were enrolled in the study after written informed consent was obtained from each participant. Twenty-four subjects (8.7%) had at least one coronary segment that was completely surrounded by myocardium. Patients ranged in age from 27 to 76 years, with an average of 54 +/- 12 years. Thirty coronary segments were found to have MB. The most common location of MB was in segment 7, which accounted for 14 coronary segments (46.7%) of the total number of bridged segments; left anterior descending artery (LAD) segments accounted for 23 (76.7%); and right coronary artery and left circumflex artery segments accounted for three (10%) and two (6.7%), respectively. The length of bridged segments ranged from 5.2 to 50.6 mm, with an average length of 24.6 +/- 11.8 mm, and the depth of the bridged segments ranged from 0.5 to 9.1 mm, with an average depth of 3.65 +/- 1.89 mm. Two bridged segments (6.7%) had concomitant atherosclerosis; these were located in segment 7 (24.0 mm long and 6.10 mm deep) and segment 8 (27.1 mm long and 7.0 mm deep). Bridged segments with concomitant atherosclerosis were deeper, but not longer, compared with bridged segments without concomitant atherosclerosis (p < 0.05). Electrocardiogram-gated MDCT is an effective noninvasive tool for evaluating MB in a clinical setting. The most common location of MB was in the LAD, especially in segment 7. Bridged segments with concomitant atherosclerosis were deeper, but not longer, compared with bridged segments without concomitant atherosclerosis.

The Angiographic Aspects of Myocardial Bridges in Turkish Patients who have Undergone Coronary Angiography

Little is known of the clinical significance of myocardial bridges, which may be recognised as the narrowing of the systolic coronary artery as seen in an angiography. In this study, our goal was to review the literature information about the anatomic aspects, the clinical manifestations and implications, and the angiographic characteristics. The angiographic data of 7200 adult patients undergoing coronary angiography were retrospectively analysed for the diagnosis of myocardial bridge. The main angiographic evidence of a myocardial bridge that we required was the narrowing of a systolic coronary artery resulting in at least 50% reduction of lumen diameter in comparison with the diastolic phase. All coronary angiograms were reviewed independently by at least 2 of the authors and the case was included only if there was a consensus that the myocardial bridge resulted in 50% narrowing or more. Myocardial bridge was present in 29 (0.4%) of the 7200 coronary angiographies. The location of the myocardial bridge was in the left anterior descending coronary artery in 28 cases (96.5%), and the left circumflex coronary artery in 1 case (3.4%). Myocardial bridge was most common in the middle segment of the left anterior descending coronary artery (78.5 %). Each of these patients with myocardial bridge was referred for angiography because of symptom of chest pain alone or symptom of chest pain, palpitations and dyspnoea. Of the 29 patients with myocardial bridge, 2 patients without any symptom, demonstrated ischaemia as assessed by Tc- 99m MIBI myocardial perfusion scintigraphy. Chest pain was the common reason for angiography in patients with myocardial bridge. The incidence of myocardial bridge may vary according to population. Myocardial bridge is more frequently found in the middle segment of the left anterior descending coronary artery.

Incidence and clinical significance of myocardial bridging with ECG-gated 16-row MDCT coronary angiography

The aims of this study were to evaluate the incidence and the clinical significance of myocardial bridging in 401 patients with chest pain examined with 16-row Multidetector CT (MDCT) coronary angiography. Four hundred nine consecutive patients who had chest pain or symptoms suggestive of coronary artery disease were involved in this study. Patients with heart rates >or=65 beats/min received 25-50 mg of atenolol orally 1 h before the scan. CT coronary angiography was performed with a 16-row MDCT scanner. CT coronary angiographic images were evaluated by consensus of two radiologists, who were blinded to clinical information. Clinical correlation was made between the presence and type of myocardial bridging on MDCT and the clinical results based on history, examination, and any subsequent clinical workup at the 2-month follow-up by a consensus of two physicians. Among the 401 patients, 23 (5.7%) cases of myocardial bridging were detected. Twenty-one (5.2%) cases of myocardial bridging were located at the middle third of the left anterior descending coronary artery (LAD), one (0.25%) case was at the proximal third of the LAD, and one (0.25%) case was at the distal third of the LAD. Superficial bridging was identified in 15 patients and deep bridging in 8. The length of tunneled artery was between 5 and 27 mm, with a mean of 15.7 mm, and the depth of tunneled artery was between 1.0 and 7.0 mm, with a mean of 3.2 mm. Out of four patients whose chest pain was assumed to be associated with myocardial bridging, three patients had deep bridging. In the other 19 patients with bridging, alternative causes of chest pain were present. We found the incidence of myocardial bridging in this patient group to be 5.7%. Larger multicenter studies are required to evaluate the incidence of myocardial bridging and to determine a link between myocardial bridging and chest pain.

Prevalence of myocardial bridging detected with 64-slice multidetector coronary computed tomography angiography in asymptomatic adults

Myocardial bridging is a congenital condition in which a segment of an epicardial artery has an intramural course within the myocardium. The aim of the present study was to evaluate the prevalence of myocardial bridging and the ability of 64-slice coronary computed tomography angiography to identify myocardial bridging in asymptomatic adults. One hundred sixty-nine consecutive asymptomatic subjects underwent 64-row multidetector computed tomography (MDCT) of the coronary arteries. Two experienced CT radiologists identified myocardial bridging >1 mm in thickness, by consensus. We examined the frequency of myocardial bridging and evaluated the length, thickness, and coronary wall lesions. Myocardial bridges were found in 28 (17%) of 165 subjects. Twenty-one subjects (75%) had 1 bridge and 7 subjects (25%) had 2, for a total of 35 myocardial bridges. Twenty-one bridges (60%) were located in the left anterior descending, 8.5% in the diagonal branch, and 2.8% in the circumflex arteries. The segment beneath the myocardial bridge was always free of coronary wall plaques, but the arterial segment proximal to it had significant coronary wall plaques in 24 cases (68.6%). We found that the incidence of myocardial bridging in asymptomatic adults is 7%, which is in agreement with some pathologic studies in the literature. Our study shows that MDCT of the coronary arteries is a reliable and noninvasive technique, which can accurately locate the site of myocardial bridging, and measure its thickness, course, and length.

Pathomorphology and Pathogenic Role of Myocardial Bridges in Sudden Cardiac Death

Pathognomonic incidence of myocardial bridges during obstructive hypertrophic cardiomyopathy, hypertension, and ischemic heart disease was established. Myocardial bridges were predominantly found in the median segments of major coronary arteries with prevailence of bridge-like obstructions in the anterior interventricular branch of the left coronary artery. Typical changes in cardiac angioarchitectonics indicating pronounced inadequacy of coronary blood flow were determined depending on the segmentary directionality of bridge obstruction. The data attest to pronounced pathogenetic role of myocardial bridges in sudden cardiac death.

Absent left main coronary artery: Angiographic findings in 83 patients with separate ostia of the left anterior descending and circumflex arteries at the left aortic sinus

Among 20,332 adult patients who underwent consecutive cardiac catheterization and coronary arteriography, 83 (0.4%) were angiographically identified as having an absent left main coronary artery. The angiographic characteristics of this coronary anomaly include: (1) the presence of two well-separated coronary ostia at the left aortic sinus resulting in separate origin of the left anterior descending and circumflex arteries; (2) an increased incidence of left coronary dominance; (3) a higher (6%) than usual (0.5% to 1.5%) incidence of myocardial bridging; (4) lack of a high incidence of congenital heart anomalies; and (5) an incidence of atheroscierotic coronary artery disease simillar to that of patients whose left main artery is intact. In 39% of the patients difficulties in selectively cannulating the separate ostium of the circumflex artery and adequately opacifying this vessel resulted in a need to change the diagnostic catheter size. Recognition of this coronary anomaly is needed to ensure accurate angiographic interpretation and is important for patients undergoing cardiac surgery to selectively perfuse these separate vessels during cardiopulmonary bypass.