Myocardial bridge and beta blockers: effect on left ventricular strain parameters.

OBJECTIVES: To assess the effect of beta-blocker treatment on left ventricular global longitudinal strain (LV Gls) as measured by echocardiography in patients with MB (Myocardial Bridge). PATIENTS AND METHODS: Between January 2019 and February 2022, a prospective, single-center study was undertaken in which myocardial bridging was identified in individuals who had coronary angiography. One hundred patients with myocardial bridging were systematically recruited and strain echocardiography was performed. Patient data were analysed in two groups - those who weren't using beta-blockers in the last six months (Group I: n = 50) vs. those who were (Group II: n = 50). RESULTS: One hundred patients participated in the study (38 females, 62 males; average age: 57.4 years). There was a statistically significant difference in the mean heart rate between groups I and II (p < 0.001). LV Gls was found to be statistically significantly improved in favour of group II when compared to group I [Group I: (-12.57)±3 vs. Group II: (-15.92)±2.9, p < 0.001]. CONCLUSION: The negative chronotropic effect of beta-blocker medication in individuals with MB identified by coronary angiography has a beneficial effect on LV Gls as measured by echocardiography.

Myocardial bridge: bridging the differential diagnosis.

A 50-year-old man with a history of vasospastic angina diagnosed 3 months prior presented with recurrent episodes of substernal chest pain. His chest pain was characterised as 'squeezing', lasting 10 min and typically occurred on awakening. Medications included isosorbide, nitroglycerin and ranolazine; however, due to lack of insurance he was unable to obtain these medications. On admission, patient was given a full-dose aspirin and nitroglycerin, which acutely worsened his chest pain. ECG did not reveal ischaemic changes and initial troponin was negative. A left heart catheterisation was conducted, revealing a myocardial bridge of the mid-left anterior descending artery. Myocardial bridge, due to its rarity, is often overlooked as an aetiology for angina, myocardial ischaemia, acute coronary syndrome, syncope and cardiac death. This case highlights the importance of broadening the differential to include myocardial bridge in the work-up for chest pain, especially if nitrates worsen symptoms.

Noninvasive assessment of myocardial bridging by coronary flow velocity reserve with transthoracic Doppler echocardiography: vasodilator vs. inotropic stimulation.

BACKGROUND: To consider hemodynamic assessment of myocardial bridging (MB) adequate, it is believed that inotropic stimulation with dobutamine should be estimated because its dynamic nature depends on the degree of extravascular coronary compression. This study evaluated comparative assessment of hemodynamic relevance of MB using coronary flow velocity reserve (CFVR) measurements by transthoracic Doppler echocardiography (TTDE) with vasodilatative and inotropic challenges. METHODS: This prospective study included forty-four patients with angiographic evidence of isolated MB of the left anterior descending coronary artery (LAD) and systolic compression of ≥50% diameter stenosis. All patients were evaluated by exercise stress-echocardiography (ExSE) test for signs of myocardial ischemia, and CFVR of the distal segment of LAD during iv.infusion of adenosine (ADO:140µg/kg/min) and iv.infusion of dobutamine (DOB:10-40µg/kg/min), separately. RESULTS: Exercise-SE was positive for myocardial ischemia in 8/44 (18%) of patients. CFVR during ADO was significantly higher than CFVR during peak DOB (2.85±0.68 vs. 2.44±0.48, p=0.002). CFVR during peak DOB was significantly lower in SE-positive group in comparison to SE-negative group (2.01±0.16 vs. 2.54±0.47, p<0.001), but not for ADO (2.47±0.51 vs. 2.89±0.70, p=0.168), respectively. Multivariable logistic analysis showed that CFVR peak DOB was the most significant predictor of functional significant MB (OR 0.011, 95%CI: 0.001-0.507, p=0.021). Receiver-operating characteristic curves have shown that TTDE-CFVR obtained by high-dose of dobutamine infusion is better than those by adenosine regarding to functional status of MB (AUC 0.861, p=0.004; AUC 0.674, p=0.179, respectively). CONCLUSIONS: Non-invasive CFVR measurement by TTDE during inotropic stimulation, in comparison to vasodilation, provides more reliable functional evaluation of MB.

Myocardial Bridging.

Myocardial bridging is rare. Myocardial bridges are most commonly localized in the middle segment of the left anterior descending coronary artery. The anatomic features of the bridges vary significantly. Alterations of the endothelial morphology and the vasoactive agents impact on the progression of atherosclerosis of myocardial bridging. Patients may present with chest pain, myocardial infarction, arrhythmia and even sudden death. Patients who respond poorly to the medical treatment with ß-blockers warrant a surgical intervention. Myotomy is a preferred surgical procedure for the symptomatic patients. Coronary stent deployment has been in limited use due to the unsatisfactory long-term results.

Myocardial bridging

Abstract Myocardial bridging is rare. Myocardial bridges are most commonly localized in the middle segment of the left anterior descending coronary artery. The anatomic features of the bridges vary significantly. Alterations of the endothelial morphology and the vasoactive agents impact on the progression of atherosclerosis of myocardial bridging. Patients may present with chest pain, myocardial infarction, arrhythmia and even sudden death. Patients who respond poorly to the medical treatment with β-blockers warrant a surgical intervention. Myotomy is a preferred surgical procedure for the symptomatic patients. Coronary stent deployment has been in limited use due to the unsatisfactory long-term results.

Isolated myocardial bridging and exercise-related cardiac events.

Myocardial bridging, which is defined as cardiac muscle overlying a part of a coronary artery, is the most common congenital coronary artery anomaly. Myocardial bridging is usually benign, but has been associated with exercise-related cardiac events. Guidelines for athletic participation in these patients are primarily based on reports from the general population with myocardial bridging. We performed a systematic literature search of PubMed, Ovid and Google Scholar for articles addressing exercise-related cardiac events associated with myocardial bridging. We identified 69 cases of which only 35 were well defined. We conclude that there are insufficient data to form definitive guidelines as to how physically active individuals with myocardial bridging should be managed. Prudence suggests that management should be individualized for those with possible symptoms. Beta adrenergic blockade is recommended as initial medical therapy. Surgery should be restricted to those with continued symptoms despite beta blocker therapy. There is no evidence that asymptomatic individuals without clinical evidence of ischemia should be restricted from vigorous activity.

[Diagnosis, prognosis and treatment of "myocardial bridging": state of the art and unresolved issues]. / Diagnosi, prognosi e terapia del "ponte intramiocardico": stato dell'arte e questioni irrisolte.

The current gold standard for the diagnosis of myocardial bridging is conventional coronary angiography; however, it shows only indirect signs of the disease, due to the systolic compression of the artery caused by the myocardial bridge with narrowing of the lumen and diastolic relaxation. On the other hand, computed tomography coronary angiography, even though exposing to radiation, clearly demonstrates the intramural course, the overlying muscular bands and the surrounding tissues also in asymptomatic patients and in absence of systolic compression. The prognosis of patients with myocardial bridge is usually good, but further studies are needed to evaluate the long-term prognosis of these patients, the adequate diagnostic and preventive approach and to better discern which patients should be candidate to medical, percutaneous or surgical treatment.

Relationship between myocardial bridging and coronary arteriosclerosis.

The objective of the study was to explore the prevalence and characteristics of myocardial bridging in patients who underwent coronary angiography and to also evaluate the correlation between bridged coronary segments and atherosclerosis. For this purpose, clinical materials of 1,500 patients who had received coronary angiography were retrospectively analyzed. The location and length of the myocardial bridge were recorded as well as the extent and location of coronary artery stenosis was described. Segments proximal and distal to the bridging were evaluated for coronary arteriosclerosis as were the remaining coronary segments. We found that myocardial bridging was present in 179 (11.9 %) patients. Bridges were frequently (84.9 %) localized in the mid-distal segment of the left anterior descending (LAD) artery. Myocardial bridging was not considered a significant risk factor for coronary atherosclerosis (odds ratio 0.58) compared with traditional cardiovascular risk factors. The incidence of coronary arteriosclerosis in the distal segments was significantly less affected than the proximal segments (P < 0.01). It was, therefore, concluded that myocardial bridging frequently localized in the mid-distal segment of the LAD artery. The presence of myocardial bridging promotes proximal atherosclerosis but it is not an additional risk factor for coronary atherosclerosis.

Efficacy of calcium channel blockers in the treatment of the myocardial bridging: a pilot study.

BACKGROUND: Myocardial Bridging (MB) is defined as a segment of a major epicardial coronary artery, the "tunnelled artery", that goes intramurally through the myocardium beneath the muscle bridge. MATERIALS AND METHODS: A 69-year-old male patient with a story of arterial hypertension and dyslipidemia in treatment with converting enzyme inhibitors (ACE-I), antiplatelet therapy and HMG-CoA reductase inhibitors and calcium channel blockers, presented with anginal-like chest pain and dyspnea. The coronary angiography showed a myocardial bridging and no hemodynamically significant coronary artery disease. RESULTS: On admission in our Department, the exercise cyclo ergometer test was significant for > 3 mm ST segment depression in the anterior and lateral leads (V3, V4, V5, V6) associated with chest pain. The coronary angiography revealed a 40% stenosis of the distal tract of the right coronary artery (RCA), a 30% stenosis of the proximal tract of the left anterior descending artery (LAD) and 40% of the proximal tract of the first diagonal branch. A 30% stenosis in the middle tract of the left circumflex coronary artery (LCX) was then detected. A marked systolic localized narrowing (90%) on the middle tract of the LAD, after the second diagonal branch (a myocardial bridge) was also detected. After eight months, the exercise cyclo ergometer test using a standard Bruce protocol was normal and, after sixteen months, no significant coronary artery disease (< 50%) and no myocardial bridging were detected by the coronary 64-multislice spiral computed tomography. Two years later, the patient was readmitted to our Department because of angina-like chest pain during light exertion in the last two months. The coronary angiography of the right system revealed a 30% stenosis of the proximal tract and a 50% stenosis of the distal tract of the RCA. The coronary angiography of the left system showed a 30% stenosis of the proximal tract of the LAD and 85% of the middle tract of the first diagonal branch. A 40% stenosis in the middle tract of the left circumflex coronary artery (LCX) was then detected. No MB of the middle tract of the LAD was detected, and a bare metal stent (Presillion 2.5 x 12 mm) was deployed in the middle tract of the first diagonal branch. CONCLUSIONS: After 2 years, the administration of the calcium channel blockers has been effective in the treatment of the MB but no effect on the atherosclerotic plaque growth has been demonstrated.

Myocardial bridging in an adult patient with d-transposition of the great arteries.

Myocardial bridging is characterized by intra-myocardial course of a segment of an epicardial coronary artery, leading to systolic compression. In most cases, it is considered a benign condition but rarely has been associated with serious cardiac events like myocardial infarction and sudden death. We describe a 25-year-old man with known d-transposition of the great arteries (d-TGA) status post-Mustard procedure who presented with palpitations and chest pain. Cardiac catheterization revealed complete systolic compression of a myocardial bridging segment of the left anterior descending artery and also complete compression of the first septal perforator during episodes of ectopic atrial tachycardia. No percutaneous or surgical interventions were performed. Symptoms improved after cautious use of beta-blockers. This appears to be the first report of symptomatic myocardial bridging in an adult patient with d-TGA.

[Myocardial bridging: therapeutic and clinical development].

BACKGROUND: The myocardial bridge constitutes one of the main differential diagnoses of coronary artery disease. However, it remains an underdiagnosed condition and its physiopathological mechanisms and therapeutics are yet to be elucidated. OBJECTIVE: To analyze and describe the clinical and therapeutic evolution of patients with an angiographic diagnosis of myocardial bridge, comparing the data with that in the current literature, in order to clarify the patients' clinical profile and prognosis. METHODS: The results of coronary angiographies carried out from 2003 to 2007 in a Laboratory of Hemodynamics were reviewed; the analysis of patients' files was carried out and selected patients were interviewed. RESULTS: The frequency of myocardial bridge diagnosis was 3.6%. The mean age of patients was 56.8 years (SD = 11.83; CI = 0.73). The anterior descending artery was affected in isolation in 100% of the cases. After the selection, the analysis and interview of 31 patients were carried out. There was no correlation between symptoms and degree of angiographic narrowing observed in the studied patients. The drug treatment included the use of beta-blockers, calcium-channel antagonists, platelet antiaggregants and/or nitrates and resulted in clinical improvement in 30%, absence of alterations in the clinical picture in 60% and symptom worsening in 10% of the patients. One patient presented sudden death; two patients underwent angioplasty followed by significant clinical improvement and none of the patients underwent surgical procedures. CONCLUSION: Most of the patients with myocardial bridge have a good prognosis, but in the long term, there are not enough data, obtained from a large sample of symptomatic patients, to draw definitive conclusions.

Ponte miocárdica: evolução clínica e terapêutica / Puente miocárdico: evolución clínica y terapéutica / Myocardial bridging: therapeutic and clinical development

FUNDAMENTO: A ponte miocárdica constitui um dos principais diagnósticos diferenciais de doença arterial coronariana. Entretanto, ainda é subdiagnosticada e tem seus mecanismos fisiopatológicos e sua terapêutica não completamente elucidados. OBJETIVO: Analisar e descrever a evolução clínica e terapêutica de pacientes com diagnóstico angiográfico de ponte miocárdica, comparando os dados com a literatura atual, a fim de elucidar o perfil clínico e o prognóstico destes pacientes. MÉTODOS: Foram revisados os resultados de cineangiocoronariografias realizadas no período de 2003 a 2007, em um laboratório de hemodinâmica, efetuando-se análise de prontuários e entrevista de um grupo de pacientes selecionados. RESULTADOS: A frequência de diagnósticos de pontes miocárdicas foi de 3,6 por cento. A idade média dos pacientes foi de 56,8 anos (DP = 11,83; IC = 0,73). A artéria descendente anterior foi acometida isoladamente em 100 por cento dos casos. Após a seleção, realizou-se análise e entrevista de 31 pacientes. Não houve correlação entre os sintomas e o grau de estreitamento angiográfico obtido nos pacientes estudados. O tratamento medicamentoso incluiu o uso de agentes? bloqueadores, antagonistas do canal de cálcio, antiagregantes plaquetários e/ou nitratos, tendo, como resultado, melhora clínica em 30 por cento, ausência de alterações no quadro clínico em 60 por cento e piora dos sintomas em 10 por cento dos pacientes. Um paciente apresentou morte súbita, dois pacientes realizaram angioplastia com melhora clínica significativa e nenhum paciente realizou procedimento cirúrgico. CONCLUSÃO: A maioria dos pacientes com ponte miocárdica tem um bom prognóstico, mas em longo prazo não há dados suficientes, realizados em um grande grupo de pacientes sintomáticos, para conclusões definitivas.

BACKGROUND: The myocardial bridge constitutes one of the main differential diagnoses of coronary artery disease. However, it remains an underdiagnosed condition and its physiopathological mechanisms and therapeutics are yet to be elucidated. OBJECTIVE: To analyze and describe the clinical and therapeutic evolution of patients with an angiographic diagnosis of myocardial bridge, comparing the data with that in the current literature, in order to clarify the patients' clinical profile and prognosis. METHODS: The results of coronary angiographies carried out from 2003 to 2007 in a Laboratory of Hemodynamics were reviewed; the analysis of patients' files was carried out and selected patients were interviewed. RESULTS: The frequency of myocardial bridge diagnosis was 3.6 percent. The mean age of patients was 56.8 years (SD = 11.83; CI = 0.73). The anterior descending artery was affected in isolation in 100 percent of the cases. After the selection, the analysis and interview of 31 patients were carried out. There was no correlation between symptoms and degree of angiographic narrowing observed in the studied patients. The drug treatment included the use of beta-blockers, calcium-channel antagonists, platelet antiaggregants and/or nitrates and resulted in clinical improvement in 30 percent, absence of alterations in the clinical picture in 60 percent and symptom worsening in 10 percent of the patients. One patient presented sudden death; two patients underwent angioplasty followed by significant clinical improvement and none of the patients underwent surgical procedures. CONCLUSION: Most of the patients with myocardial bridge have a good prognosis, but in the long term, there are not enough data, obtained from a large sample of symptomatic patients, to draw definitive conclusions.

FUNDAMENTO: El puente miocárdico constituye uno de los principales diagnósticos diferenciales de la enfermedad arterial coronaria. No obstante, aún está subdiagnosticado y sus mecanismos fisiopatológicos y su tratamiento no están completamente esclarecidos. OBJETIVO: Analizar y describir la evolución clínica y terapéutica de pacientes con diagnóstico angiográfico de puente miocárdico, comparando los datos con la literatura actual, a fin de clarificar el perfil clínico y el pronóstico de estos pacientes. MÉTODOS: Se revisaron los resultados de cinecoronariografias realizadas entre los años 2003 y 2007, en un laboratorio de hemodinamia, conjuntamente con el análisis de historias clínicas y la realización de entrevistas a un grupo de pacientes seleccionados. RESULTADOS: La frecuencia del diagnóstico de puente miocárdico fue del 3,6 por ciento. La edad promedio de los pacientes fue de 56,8 años (DE = 11,83; IC = 0,73). La arteria descendente anterior fue afectada aisladamente en el 100 por ciento de los casos. Tras la selección, se realizaron análisis y entrevistas a 31 pacientes. No existió correlación entre los síntomas y el grado de estrechamiento angiográfico obtenido en los pacientes estudiados. El tratamiento medicamentoso incluyó el uso de betabloqueantes, antagonistas de los canales de calcio, antiagregantes plaquetarios y/o nitratos, obteniendo, como resultado, mejoría clínica en el 30 por ciento, ausencia de alteraciones en el cuadro clínico en el 60 por ciento y empeoramiento de los síntomas en el 10 por ciento de los pacientes. Un paciente presentó muerte súbita; en dos pacientes se practicó una angioplastia con mejoría clínica significativa y ningún paciente fue sometido a un procedimiento quirúrgico. CONCLUSIÓN: La mayoría de los pacientes con puente miocárdico tiene un buen pronóstico, pero no hay datos suficientes a largo plazo, que permitan sacar conclusiones definitivas, mediante el seguimiento de un grupo numeroso de pacientes ...

Long-term clinical course of patients with isolated myocardial bridge.

BACKGROUND: Myocardial bridge (MB) is regarded as a common benign lesion on coronary angiography (CAG). It is known to be harmless but may cause several cardiac events and recurrent hospitalization, so in the present study the long-term clinical course of patients with isolated MB and predictors of readmission were investigated. METHODS AND RESULTS: Total 684 patients (343 males, 60.5+/-11.2 years) with persistent chest pain without critical stenosis on CAG were enrolled. The patients were divided into 2 groups according to the presence of MB. Clinical follow-up was performed with respect to readmission after baseline CAG. At a mean follow-up of 37 months, 92 patients (13.3%) were re-admitted because of 79 recurrent chest pain refractory to medication (11.5%), 8 myocardial infarctions (1.2%), 1 life-threatening arrhythmia (0.1%) and 4 deaths (0.6%). There was a significant higher incidence of readmission in the MB group (P=0.038). In multivariate analysis, long MB (hazard ratio (HR) 2.780; 95% confidence interval (CI) 1.070-7.218, P=0.036) and spontaneous vasospasm in CAG (HR 2.335; 95%CI 1.055-5.171, P=0.037) were the predictors of readmission. Moreover, additional use of aspirin or statin decreased the readmission rate. CONCLUSIONS: This study suggests that MB on non-occlusive CAG is not benign and may cause recurrent chest pain, myocardial infarction or life-threatening arrhythmia. Especially, patients with a long MB and vasospasm on CAG need intensive medical therapy, including antiplatelet treatment.

Coronary myocardial bridge constitutes a risk: But how to manage it?

Myocardial bridges may cause angina pectoris, myocardial infarction, life threatening arrhythmias and even sudden cardiac death but most of them are harmless. Although the exact management is not well known, beta blockers seem to be the first choice. Stenting is controversial and one must think "twice" before stenting the bridged coronary artery.