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Comprehensive functional and anatomic assessment of myocardial bridging: Unlocking the Gordian Knot.Frontiers in Cardiovascular Medicine 2022Myocardial bridging (MB) is the most frequent congenital coronary anomaly in which a segment of an epicardial coronary artery takes a tunneled course under a bridge of... (Review)
Review
Myocardial bridging (MB) is the most frequent congenital coronary anomaly in which a segment of an epicardial coronary artery takes a tunneled course under a bridge of the myocardium. This segment is compressed during systole, resulting in the so-called "milking effect" at coronary angiography. As coronary blood flow occurs primarily during diastole, the clinical relevance of MB is heterogeneous, being usually considered an asymptomatic bystander. However, many studies have suggested its association with myocardial ischemia, anginal symptoms, and adverse cardiac events. The advent of contemporary non-invasive and invasive imaging modalities and the standardization of intracoronary functional assessment tools have remarkably improved our understanding of MB-related ischemia, suggesting the role of atherosclerotic lesions proximal to MB, vasomotor disorders and microvascular dysfunction as possible pathophysiological substrates. The aim of this review is to provide a contemporary overview of the pathophysiology and of the non-invasive and invasive assessment of MB, in the attempt to implement a case-by-case therapeutic approach according to the specific endotype of MB-related ischemia.
PubMed: 36426224
DOI: 10.3389/fcvm.2022.970422 -
The Journal of Invasive Cardiology Nov 2015Myocardial bridging is a congenital anomaly in which a segment of a coronary artery takes a "tunneled" intramuscular course under a "bridge" of overlying myocardium.... (Review)
Review
Myocardial bridging is a congenital anomaly in which a segment of a coronary artery takes a "tunneled" intramuscular course under a "bridge" of overlying myocardium. This causes vessel compression in systole, resulting in hemodynamic changes that may be associated with angina, myocardial ischemia, acute coronary syndrome, left ventricular dysfunction, arrhythmias, and even sudden cardiac death. While described on autopsy for centuries, technological advances such as coronary computed tomography angiography and intravascular ultrasound have contributed greatly to our understanding of the anatomic, hemodynamic, and pathophysiological consequences of systolic compression. Atherosclerosis preferentially develops immediately proximal to the bridged segment, likely due to alterations in shear stress, while the compressed segment itself is often spared. First-line therapy of symptomatic bridging remains medical treatment with beta-blockers and non-dihydropyridine calcium-channel blockers, and nitrates are contraindicated. Surgical myotomy, intracoronary stenting, and coronary artery bypass graft surgery have been used for refractory symptoms, but long-term outcomes remain uncertain. Further research is required to better define the patient population that would derive the greatest benefit from surgical and percutaneous intervention.
Topics: Coronary Angiography; Coronary Vessels; Global Health; Humans; Myocardial Bridging; Percutaneous Coronary Intervention; Prevalence; Ultrasonography, Interventional
PubMed: 25999138
DOI: No ID Found -
Cureus Aug 2023Myocardial bridging (MB) is a congenital coronary artery anomaly involving an overlying myocardium's partial or complete encasement of a coronary artery segment. The... (Review)
Review
Myocardial bridging (MB) is a congenital coronary artery anomaly involving an overlying myocardium's partial or complete encasement of a coronary artery segment. The obstruction can lead to significant cardiac symptoms, resulting in myocardial ischemia, arrhythmia, and sudden cardiac death. Several approaches, including invasive and non-invasive methods, have been proposed to diagnose and manage MB. Invasive modalities, such as intravascular ultrasound (IVUS) and coronary angiography, offer high specificity and sensitivity. In contrast, non-invasive methods like Doppler ultrasound, multislice computed tomography (MSCT), and magnetic resonance imaging (MRI) are advantageous due to their non-invasive nature, high sensitivity and specificity, and cost-effectiveness. Treatment options for MB mainly focus on relieving symptoms and preventing adverse outcomes. The use of pharmacological agents and surgical and percutaneous interventions has been documented in numerous studies. Studies conclude that MB is a treatable cardiac anomaly, and a combined approach of diagnosis, treatment, and follow-up is necessary to reduce the morbidity and mortality associated with this condition.
PubMed: 37692750
DOI: 10.7759/cureus.43132 -
Journal of the American College of...
Topics: Humans; Myocardial Bridging
PubMed: 25457409
DOI: 10.1016/j.jacc.2014.09.009 -
European Cardiology Feb 2021Myocardial bridging occurs when coronary arteries run intramurally. Episodes of tachycardia can cause a dynamic obstruction that extends into diastole, compromising... (Review)
Review
Myocardial bridging occurs when coronary arteries run intramurally. Episodes of tachycardia can cause a dynamic obstruction that extends into diastole, compromising coronary filling time, and subsequently leading to ischaemia. Myocardial ischaemia, acute coronary syndrome, coronary spasm, myocardial stunning, arrhythmia, takotsubo cardiomyopathy, and sudden cardiac death have all been reported with bridging. Atherosclerotic plaques develop proximally in the bridge due to low shear stress and high oscillatory wall-flow. Factors affecting atherosclerotic build-up include disrupted flow patterns (particularly flow recirculation, which exacerbates LDL internalisation), cell adhesion and monocyte adhesion to the endothelium. Endothelial health depends on arterial flow patterns, given that the vessel reacts differently to various flow types, as confirmed in 3D simulations. Medication is the first-line therapy, while surgical de-roofing and coronary bypass are reserved for severe stenosis. Distinguishing physiological arterial compression from pathological stenosis is essential. Deeper bridges correlating with recurrent angina with an instantaneous wave-free ratio ≤0.89 or fractional flow reserve ≤0.80 are treated.
PubMed: 33737959
DOI: 10.15420/ecr.2020.33 -
Pediatrics and Neonatology Apr 2018Pediatric cardiomyopathies are a group of myocardial diseases with complex taxonomies. Cardiomyopathy can occur in children at any age, and it is a common cause of heart... (Review)
Review
Pediatric cardiomyopathies are a group of myocardial diseases with complex taxonomies. Cardiomyopathy can occur in children at any age, and it is a common cause of heart failure and heart transplantation in children. The incidence of pediatric cardiomyopathy is increasing with time. They may be associated with variable comorbidities, which are most often arrhythmia, heart failure, and sudden death. Medical imaging technologies, including echocardiography, cardiac magnetic resonance, and nuclear cardiology, are helpful in reaching a diagnosis of cardiomyopathy. Nevertheless, endomyocardial biopsy is the final diagnostic method of diagnosis. Patients warrant surgical operations, such as palliative operations, bridging operations, ventricular septal maneuvers, and heart transplantation, if pharmaceutical therapies are ineffective. Individual therapeutic regimens due to pediatric characteristics, genetic factors, and pathogenesis may improve the effects of treatment and patients' survival.
Topics: Biopsy; Cardiomyopathies; Child; Echocardiography; Humans; Palliative Care
PubMed: 29454680
DOI: 10.1016/j.pedneo.2017.05.003 -
Journal of Clinical Medicine May 2023Myocardial bridging (MB) is the most frequent congenital coronary anomaly characterized by a segment of an epicardial coronary artery that passes through the myocardium.... (Review)
Review
Myocardial bridging (MB) is the most frequent congenital coronary anomaly characterized by a segment of an epicardial coronary artery that passes through the myocardium. MB is an important cause of myocardial ischemia and is also emerging as a possible cause of myocardial infarction with non-obstructed coronary arteries (MINOCA). There are multiple mechanisms underlying MINOCA in patients with MB (i.e., MB-mediated increased risk of epicardial or microvascular coronary spasm, atherosclerotic plaque disruption and spontaneous coronary artery dissection). The identification of the exact pathogenetic mechanism is crucial in order to establish a patient-tailored therapy. This review provides the most up-to-date evidence regarding the pathophysiology of MINOCA in patients with MB. Moreover, it focuses on the available diagnostic tools that could be implemented at the time of coronary angiography to achieve a pathophysiologic diagnosis. Finally, it focuses on the therapeutic implications associated with the different pathogenetic mechanisms of MINOCA in patients with MB.
PubMed: 37297993
DOI: 10.3390/jcm12113799 -
Heart Views : the Official Journal of... 2023Myocardial bridging (MB) is the course of the epicardial segment of a coronary artery within the myocardium. The systolic compression of this segment called the tunneled...
BACKGROUND
Myocardial bridging (MB) is the course of the epicardial segment of a coronary artery within the myocardium. The systolic compression of this segment called the tunneled segment may lead to alterations in blood flow to the heart. We have studied the gross and microscopic features of MB in cases of sudden cardiac death and analyzed its characteristics and whether there is any association with other clinicopathological characteristics which may help us to understand the pathogenesis and risk stratification.
MATERIALS AND METHODS
This is a retrospective descriptive study of 132 postmortem heart specimens of sudden cardiac death. The coronary arteries were dissected, and MB and its characteristics were studied. Statistical analysis was performed using the Chi-square and Fisher's exact tests ( < 0.05 significant).
RESULTS
MB was present in 28 cases (21.2%), with a mean age of 49.5 years and male:female ratio of 27:1. MB was seen in the left anterior descending artery in 86.2% of cases, the right coronary artery in 10%, and left circumflex artery in 3.5% of cases. Atherosclerosis was seen in the segment proximal to the tunneling in 89.2% of cases leading to infarction in four cases. Left ventricular hypertrophy (LVH) was significantly associated with MB cases (19/68%) ( < 0.05).
CONCLUSION
MB causes turbulence of blood in the proximal segment leading to coronary atherosclerosis, thereby predisposing the heart to ischemic changes and LVH and may lead to infarction in a few cases.
PubMed: 37124430
DOI: 10.4103/heartviews.heartviews_79_22 -
Annals of Noninvasive Electrocardiology... Mar 2015Myocardial bridging (MB) occurs when a segment of an epicardial coronary artery takes an intra- myocardial course, thus leading to systolic compression. Most myocardial... (Review)
Review
BACKGROUND
Myocardial bridging (MB) occurs when a segment of an epicardial coronary artery takes an intra- myocardial course, thus leading to systolic compression. Most myocardial bridges involve the left anterior descending artery and are observed in 14-35% of patients. Different pathophysiological mechanisms can induce symptoms secondary to myocardial ischemia: systolic coronary compression, diastolic dysfunction associated with aging and coronary atherosclerosis, LV hypertrophy, vasospasm, microvascular and endothelial dysfunction, plaque development proximal to the bridge.
METHODS
We performed a literature review of MB, with a particular emphasis on electrocardiographic manifestations.
RESULTS
Stable angina-like chest pain is the usual presentation and MB should be suspected in patients at low risk for coronary atherosclerosis which refer this symptom or which present myocardial ischemia at instrumental examinations. ECG changes are not specific for MB and resting ECG is often normal or presents ST segment anomalies. Exercise stress test often shows non specific signs of ischemia, conduction disturbances or arrhythmias which do not allow the distinction between myocardial bridging and other causes of myocardial ischemia; angina often appears during exercise, even in the absence of ECG changes. Myocardial perfusion deficits at scintigraphy are neither obligatory nor specific. Although the clinical significance of MB is still debated, MB has been associated with acute coronary syndrome, coronary vasospasm, and even sudden cardiac death.
CONCLUSION
Although MB may lead to myocardial ischemia during stress, its clinical presentation and electrocardiographic findings are not specific.
Topics: Electrocardiography; Humans; Myocardial Bridging
PubMed: 25530097
DOI: 10.1111/anec.12242 -
Heart Rhythm Apr 2010The J wave, also referred to as an Osborn wave, is a deflection immediately following the QRS complex of the surface ECG. When partially buried in the R wave, the J wave... (Review)
Review
The J wave, also referred to as an Osborn wave, is a deflection immediately following the QRS complex of the surface ECG. When partially buried in the R wave, the J wave appears as J-point elevation or ST-segment elevation. Several lines of evidence have suggested that arrhythmias associated with an early repolarization pattern in the inferior or mid to lateral precordial leads, Brugada syndrome, or arrhythmias associated with hypothermia and the acute phase of ST-segment elevation myocardial infarction are mechanistically linked to abnormalities in the manifestation of the transient outward current (I(to))-mediated J wave. Although Brugada syndrome and early repolarization syndrome differ with respect to the magnitude and lead location of abnormal J-wave manifestation, they can be considered to represent a continuous spectrum of phenotypic expression that we propose be termed J-wave syndromes. This review summarizes our current state of knowledge concerning J-wave syndromes, bridging basic and clinical aspects. We propose to divide early repolarization syndrome into three subtypes: type 1, which displays an early repolarization pattern predominantly in the lateral precordial leads, is prevalent among healthy male athletes and is rarely seen in ventricular fibrillation survivors; type 2, which displays an early repolarization pattern predominantly in the inferior or inferolateral leads, is associated with a higher level of risk; and type 3, which displays an early repolarization pattern globally in the inferior, lateral, and right precordial leads, is associated with the highest level of risk for development of malignant arrhythmias and is often associated with ventricular fibrillation storms.
Topics: Arrhythmias, Cardiac; Electrocardiography; Humans
PubMed: 20153265
DOI: 10.1016/j.hrthm.2009.12.006