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.

Myocardial Bridging: a bridge to spasm?

Abstract Introduction Myocardial bridges (MBs) represent a congenital anomaly where a segment of a coronary artery passes through the myocardium, resulting in systolic compression. The role of MBs in causing chest pain has been debated, as coronary blood flow occurs primarily in diastole. MBs are generally considered benign, there is growing evidence implicating them in the pathogenesis of coronary artery spasm (CAS). However, the prevalence of CAS in patients in Europe with MBs, particularly assessed through acetylcholine (ACh) testing, remains poorly defined. Methods We conducted a retrospective analysis of consecutive patients with angina with no obstructive CAD (ANOCA), ischemia with no obstructive CAD (INOCA), or myocardial infarction with no obstructive coronary arteries (MINOCA) undergoing ACh testing between 2021 and 2024 at our centre. Patients with documented MBs on coronary angiography were included. The presence of epicardial CAS, defined as >90% reduction in coronary diameter with symptoms and/or ischemic electrocardiographic changes, was assessed during ACh provocation testing. Clinical characteristics, Fractional flow reserve (FFR), resting full-cycle ratio (RFR), coronary flow reserve (CFR) and the index of microvascular resistance (IMR) were also analyzed. Results From a total of 299 patients who underwent ACh Testing, 21 patients were identified with MBs, (17 Male, 4 Female). The prevalence of focal CAS in the MB among these patients was 90%. None of these patients had abnormal hyperemic (FFR) or non-hyperemic (RFR) measurements. 9 of the 21 patients with MB had increased IMR, and only 1 had a CFR < 2. 1 Patient had both microvascular CAS in addition to focal epicardial CAS. Conclusion This analysis provides valuable insights into the prevalence of CAS in patients with MBs undergoing ACh testing. The findings underscore the importance of considering CAS in the evaluation and management of patients with MBs, particularly during provocative testing. Further prospective studies are warranted to validate these findings and elucidate the clinical implications for risk stratification and treatment strategies in this patient population.

The role of myocardial bridging in athletes with ST-segment depression or T-wave inversion on exercise testing

Abstract Background Myocardial bridging (MB) is a congenital anomaly in which a myocardial band partially or completely covers a coronary artery. It is a common finding in the general population, but it is more frequent in athletes. MB can cause ST-segment depression on exercise testing, which can be misinterpreted as coronary artery disease and generate the prohibition of sports. Aim To evaluate the presence of Myocardial Bridging (MB) through Multi-Slice Tomography Angiography in Moderate to High Intensity Athletes with Electrocardiographic changes and normal parietal motility in Stress Ultrasound with Exercise Methods This study included 159 athletes who had ST-segment depression or T-wave inversion on exercise testing. All participants underwent coronary angiography and/or multislice computed tomography coronary angiography. In addition, follow-up was 36 months (+/- 18 months) to assess the presence of major adverse cardiovascular events (MACE). Results A total of 3790 stress tests were requested from the Cardiology and Sports Clinic: 3631 (95.8%) were completely normal (no ST changes and normal parietal motility) and 159 (4.2%) showed ST segment depression. Of the 159 athletes, 42 (1.11%) had ST depression in the inferior and/or lateral segments and abnormal parietal motility at maximal exercise and were referred for invasive coronary angiography. The remaining 117 (3.09%) had the following ECG changes: 88 (72.21%) inferior and/or lateral ST segment depression and 29 (24.78%) T wave inversion without ST segment depression. Ninety-two (78.64%) of the above 117 athletes were diagnosed with 1 or more MBs in the coronary arteries. One hundred and forty-three MBs were found. The most common location was the anterior descending coronary artery (n=61; 42.6%) in its middle and distal third, followed by findings in the diagonal (n=30; 20.9%), circumflex (n=28; 19.5%) and marginal (n=24; 16.7%) branches. No MACE was recorded during the follow-up period and no further complex diagnostic studies were required. Conclusions Our study suggests that MB is a common cause of ST-segment depression and/or T-wave inversion on exercise testing in athletes. MB is usually benign and does not increase the risk of cardiovascular events. Therefore, athletes with MB should be allowed to continue participating in sports.ECG during maximal exercise stress echocTMSC of athlete

Association of vasospastic angina with myocardial bridging and pericoronary adipose tissue attenuation on computed tomography angiography

Abstract Background Recent studies have suggested that vasospastic angina (VSA) is associated with myocardial bridging (MB). The relationship between VSA and pericoronary adipose tissue (PCAT) inflammation has also been reported but still remains to be determined. Purpose We investigated clinical and coronary computed tomography angiographic (CCTA) features in patients with VSA diagnosed by spasm provocation test (SPT). Methods We retrospectively studied patients with clinically suspected VSA who underwent both SPT with intracoronary acetylcholine administration and CCTA within three months before SPT at Tsuchiura Kyodo General Hospital. PCAT inflammation was evaluated on CCTA images by fat attenuation index (FAI) which has been recently used as a novel biomarker of coronary inflammation. In FAI analysis, we measured FAI of the proximal segments not only for 4mm (FAI4mm) but also for the inner and thinner 2mm pericoronary adipose tissue layer from the vessel wall (FAI2mm), since FAI2mm has been reported to provide better discriminating efficacy for VSA diagnosis than FAI4mm. We also evaluated the presence or absence of MB and its features including length, depth and location on CCTA images. Results A total of 172 patients were studied and VSA was diagnosed in 39.0% (67/172) of patients by SPT according to the latest guideline. Male (74.6% vs 49.5%, P=0.001), smoking history (74.6% vs 48.6%, P=0.001) were more frequent, and prevalence of CCTA-defined MB (47.8% vs 34.3%, P=0.082) and RCA-FAI2mm (-68.73 HU vs -73.35 HU, P<0.001) were higher in patients with versus without VSA. In multivariable analysis, presence of CCTA-defined MB (odds ratio [OR] 2.56, 95% confidence interval [CI] 1.26-5.19, P=0.0095), RCA-FAI2mm (OR 1.05, 95% CI 1.01-1.09, P=0.025), and smoking (OR 3.40, 95% CI 1.57-7.36, P=0.0019) were independently associated with VSA. A combination of high RCA-FAI2mm (≥-68.93HU, the best cut-off obtained by ROC analysis with AUC of 0.64, 95% CI 0.551 - 0.728), smoking history and existence of MB could predict VSA with 73.7% of probability, while an absence of all 3 covariates could exclude VSA with 85.3% of probability. Conclusion CCTA-defined MB, high RCA-FAI2mm and smoking were independently predictive of VSA.

Comparison of adenosine, dobutamine and bicycle exercise on intracoronary physiological indices in patients with myocardial bridges

Abstract Background We have recently demonstrated that patients with angina and nonobstructive coronary arteries (ANOCA) with myocardial bridges (MBs) exhibit maladaptive exercise physiology, due to abnormal wave energies arising at the tunnelled segment (1). Intracoronary pressure-derived indices in response to dobutamine and adenosine are used to identify an ischaemic substrate in these patients in clinical practice (2). However, it remains unknown if the changes induced by dobutamine and adenosine are comparable with physical exercise. Methods Patients with ANOCA and a MB in the left anterior descending artery underwent simultaneous acquisition of intracoronary pressure and flow sequentially during rest, supine bicycle exercise and intravenous adenosine and dobutamine infusion. We compared coronary perfusion efficiency (accelerating energy/total energy flux) and changes in specific wave energies in response to these three stressors. Results Twenty-five patients were enrolled (36% females, 59±9 years old). Patients had a high symptom burden (88% CCS II-IV) and myocardial bridge muscle index (79±30). Fractional flow reserve and coronary flow reserve were 0.86±0.05 and 2.5±0.5. Microvascular resistances during adenosine, dobutamine and exercise were 2.0±0.7, 3.4±1.4 and 4.3±1.3 mmHg.cm-1.s-1 respectively (p<0.001). There was a reduction in coronary perfusion efficiency in response to adenosine (64±8% to 51±12%), dobutamine (65±9% to 53±13%) and exercise (66±10% to 56±9%) (all p<0.001), with no between stressor differences in delta perfusion efficiency (ANOVA p=0.641). However, the impact of each stressor on the wave energy arising from the tunnelled segment was different whereas no such difference (between stressors) was observed in the wave energies arising from the microcirculation. There was no difference in tunnelled-segment derived delta wave energies between dobutamine and exercise (Figure 1). Conclusions Adenosine, dobutamine and exercise have different effects on coronary microvascular resistance and cardiac coronary coupling in patients with myocardial bridges. Our findings provide novel mechanistic insights into the pathophysiology of ANOCA in combination with MB, and suggest that dobutamine (but not adenosine) could be used as a surrogate for physical exercise during intracoronary physiological assessment.Figure 1.

Coronary Computed Tomographic Angiography (CCTA) in non-ST elevation acute coronary syndromes

Abstract Background In patients presenting with an acute coronary syndrome (ACS), a diverse range of coronary artery disease is observed from structurally normal vessels to non-obstructive atherosclerosis and severe/obstructive coronary artery disease (CAD). In current clinical practice guidelines, the main diagnostic route for optimal management of patients with non-ST segment elevation acute coronary syndrome is invasive coronary angiography. However, in 30-40% of cases, no significant coronary lesions are evident. The purpose of this study is to describe the role of coronary computed tomographic angiography (CCTA) in non-ST elevation acute coronary syndromes in low and intermediate risk patients. Methods We describe the results of 504 patients evaluated with a protocol that includes the use of CCTA in patients with ACS. Patients over 18 years of age with a diagnosis of ACS without ST elevation who did not meet high-risk criteria (hemodynamic instability, dynamic changes in the ST segment or T wave, ventricular arrhythmia, GRACE score >140, refractory angina, heart failure or cardiorespiratory arrest) were included. They underwent CCTA as the initial coronary evaluation. Data collection was carried out between May 11, 2022 and February 20, 2024. Results 504 patients were included, with a mean age of 58 years, of which 44% were women and 56% men. Among the admission diagnoses, 26% were NSTEMI and 74% were unstable angina according to the 4th universal definition of acute myocardial infarction (AMI). The median high-sensitivity cardiac troponin T value was 7 nanograms per liter (interquartile range, 7 to 15) for the first troponin measurement. CCTA was performed in 93% of the patients. It was observed that 28% did not have any coronary lesions or plaques. 36% had non-obstructive coronary artery disease (plaques <50%). The rest had significant lesions in at least one vessel (27%), predominantly in the left anterior descending artery, or were nondiagnostic (9%). 31% had myocardial bridges, while in 13% of the patients a high-risk plaque was found. 38% of the patients included underwent invasive coronary angiography and 23% required revascularisation. Conclusion This study shows that the prevalence of ACS with coronary arteries without significant lesions by CCTA was 28%, which suggests CCTA could have a predominant role in the diagnostic algorithm of acute coronary syndromes without high-risk criteria, implying a decrease in the need of invasive studies in these patients. Only 38% required invasive coronary angiography, while revascularisation was performed in 23% of the patients. Furthermore, CCTA allowed a better detection of non-obstructive coronary artery disease (NOCAD) in 36% of the patients, and a more complete characterization of the atherosclerotic plaque, which could prompt to an initiation of preventive therapies or the optimization of medical treatment in these patients.Table 1CCTA findings

Symptom assessment and angina classification of patients with ischemia and nonobstructive coronary arteries undergoing invasive coronary function testing: from the DISCOVER INOCA multicenter registry

Abstract Background Patients with ischemia and nonobstructive coronary arteries (INOCA) suffer from a broad range of anginal symptoms that may differ depending on the biologic sex of the patient, the underlying coronary vasomotor disorder, or the type of presentation. Purpose We sought to characterize the symptom description and angina classification of patients referred for invasive coronary function testing (CFT) in the DISCOVER INOCA multicenter registry, stratified by type of presentation (stable vs unstable), biologic sex, and underlying diagnosis, including coronary microvascular dysfunction (CMD), vasospastic angina (VSA), or other disorders such as symptomatic myocardial bridging. Methods DISCOVER INOCA is a prospective, multicenter registry in the United States that includes patients who are referred for clinically indicated coronary angiography and found to have INOCA. All patients underwent protocol-guided angiography, acetylcholine provocation, coronary thermodilution, and intravascular imaging. Symptom characteristics were compared between groups. Results From September 2022 until February 2024, 104 patients were enrolled, 78% were female, and mean age was 57 ± 11 years. The post-procedure diagnosis was CMD in 19%, VSA in 41%, a mixed syndrome in 15%, or other diagnosis in 26%. The average coronary flow reserve (CFR) was 2.9 ± 1.1 in the CMD group and 5.3 ± 3.0 in the VSA group, (p < 0.001). 53% of patients presented with stable angina and 47% with unstable or progressive symptoms. Symptoms included chest pain (89%), chest tightness (42%), chest pressure (39%), shortness of breath (53%), and fatigue (16%), and no significant differences were reported when stratified by diagnostic phenotype. Female patients were more likely to report arm/neck/back/jaw pain (25% vs 5% in men, p = 0.038). Symptom triggers included exertion/activity in 73%, emotional stress in 12%, and resting symptoms in 58%. In female patients 4% reported catamenial symptoms. Of patients with stable angina, the Canadian Cardiovascular Society (CCS) Angina Classification was Grade I in 25%, Grade II in 52%, Grade III in 21%, and Grade IV in 2%. In patients with unstable angina, the Braunwald Angina Classification was Class I in 9%, Class II in 73%, and Class III in 18%. Conclusions Patients with INOCA referred for clinically indicated coronary angiography and CFT were predominantly female and most commonly reported chest pain as a presenting symptom. Female patients were more likely to report arm/neck/back/jaw pain than male patients. Over half of patients reported resting symptoms with no differences between the diagnostic phenotypes (CMD, VSA, or other). The CCS and Braunwald angina classification indicated that most patients had moderate intensity symptoms. Patient-reported outcome measures will be used to systematically categorize the symptom burden in these patients.

Bioresorbable stent unloading during percutaneous coronary intervention: Early detection and management

In this letter, we comment on a recent case report by Sun et al in the World Journal of Cardiology . The report describes the successful management of a rare complication: The unloading or detachment of a bioresorbable stent (BRS) during percutaneous coronary intervention (PCI) in a male patient. The unloading of BRS was detected via angiography and intravascular ultrasound (IVUS) imaging of the left coronary artery and left anterior descending artery. Although this case is interesting, the authors’ report lacked crucial details. Specifically, insufficient information about the type of BRS used, potential causes of BRS unloading, or whether optical coherence tomography (OCT) imaging for coronary arteries was performed before, during, or after PCI. The OCT imaging of coronary arteries before PCI can potentially prevent BRS unloading due to its higher resolution compared to IVUS. In addition, despite detecting myocardial bridging during the PCI, the authors did not provide any details regarding this variation. Here we discuss the various types of BRS, the importance of OCT in PCI, and the clinical relevance of myocardial bridging.

Utility of the AngelMed Guardian System in myocardial bridging: a case report

BackgroundMyocardial bridging (MB) is a known congenital anomaly in which a segment of the coronary artery transverses from the epicardium through the myocardium. MB may clinically manifest as recurrent angina, acute coronary syndrome, ventricular dysrhythmia, and even sudden cardiac death. On electrocardiogram (EKG), MB can present with findings consistent with significant ST-segment changes. The AngelMed Guardian System (the Guardian device) was developed in an effort to optimize the time from the onset of myocardial ischemia to intervention. The device analyzes myocardial electrical changes and alerts the patient to seek emergent medical evaluation if an acute ST-segment deviation is detected. We describe the first documented case of the Guardian device detecting acute ST-segment changes secondary to myocardial bridging.Case PresentationA 50-year-old male, with a history of percutaneous coronary intervention of the proximal left anterior descending (LAD) artery, presented to his cardiologist’s office with reports of recurrent, atypical chest pain. The Guardian device was implanted. One month after implantation, the patient experienced chest pain and was alerted by the Guardian device to seek emergent medical evaluation. Initial EKG and high-sensitivity troponins were negative for acute ischemia. Guardian device interrogation revealed significant ST depressions, encouraging further ischemic evaluation. The exercise myocardial perfusion imaging revealed an apical reversible defect. Left heart catheterization revealed a large segment of mid-LAD MB with the patient’s previous LAD stent noted to be widely patent along with no evidence of new obstructive coronary disease. Following the identification of the MB, medication regimen adjusted and the patient denied recurrence of chest pain or Guardian alerts.ConclusionsWe describe the first documented case of the Guardian device detecting acute ST-segment changes that were secondary to myocardial bridging. The Guardian device appropriately documented an ischemic event not appreciated with initial EKG or troponin testing. With the assistance of the Guardian device, we were able to rapidly identify MB as the cause for the ischemic EKG changes and subsequent abnormal stress test, optimize medical management, and prevent recurrent atypical chest pain along with office and hospital visits.

Clinical Outcomes of Concomitant Coronary Artery Bypass Grafting During Ventricular Septal Myectomy.

The clinical characteristics and survival outcomes of patients who underwent concomitant coronary artery bypass grafting during septal myectomy have not been well studied. We reviewed patients who underwent both septal myectomy and coronary artery bypass grafting from 2009 to 2020. Causes of concomitant grafting and their impact on survival were analyzed. The median follow-up period was 5.1 years. A total of 320 patients underwent both grafting and myectomy. Of these, 69.7% and 28.1% underwent grafting attributed to atherosclerotic coronary artery disease and myocardial bridging, respectively. Patients who underwent grafting for coronary artery disease tended to be older, had a longer bypass time, and required more grafts compared with patients undergoing procedures because of myocardial bridging (all P<0.05). Postoperatively, the left ventricular outflow gradient significantly decreased from 85.4 mm Hg to 12.8 mm Hg (P<0.001) without perioperative death. The cumulative survival rates were 96.2% and 97.6% at 5 years in the coronary artery disease and myocardial bridging groups, respectively, and they were comparable to that of general myectomy cohort (hazard ratio [HR], 1.06 [95% CI, 0.47-2.36], P=0.895 and HR 0.75 [95% CI, 0.23-2.46], P=0.636, respectively). Sudden death accounted for 45.5% (5 of 11) of postoperative mortality. Analysis of composite end point events showed decreased morbidity with at least one arterial graft in the overall cohort (HR, 0.47 [95% CI, 0.23-0.94], P=0.034). Concomitant grafting in septal myectomy was found to be a safe procedure. Patients who underwent such surgery experienced favorable postoperative outcomes comparable to those who underwent septal myectomy alone, with a 5-year survival rate of >95% and improved functional class of >90%.

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.

The effects of myocardial bridging on two-dimensional myocardial strain during dobutamine stress echocardiography.

Myocardial bridging (MB) is a common anatomic variant in coronary arteries with unclear functional significance. We evaluated regional myocardial strain by speckle tracking during dobutamine stress echocardiography (DSE) in patients with MB in the left anterior descending coronary artery (LAD). We studied 11 patients with MB in the LAD and no obstructive coronary artery disease (CAD), 7 patients without MB, but obstructive CAD in the LAD, and 12 controls without MB or obstructive CAD. MB was defined as either > 1mm (superficial) or > 2mm (deep) intramyocardial course of the LAD in coronary CT angiography. Regional longitudinal, radial and circumferential strains and strain rates as well as post-systolic strain index (PSI) were measured at rest, peak stress, and early recovery (1min after stress). Strain parameters during DSE were similar in the myocardium distal to MB and other myocardial regions of the same patients as well as the LAD territory in controls. However, patients with obstructive CAD showed impaired LS and strain rate as well as increased PSI at peak stress. None of the MB was associated with systolic compression in invasive coronary angiography and strain parameters were similar between superficial and deep MB. Stress myocardial blood flow by positron emission tomography correlated with LS and RS at peak stress in the myocardium distal to MB (r = -0.73, p = 0.03, and r = 0.64, p = 0.04, respectively). Myocardial strain is not reduced during DSE in patients with MB in the LAD and no significant systolic compression.

Robotic Totally Endoscopic Off-Pump Unroofing of Myocardial Bridge: Early Experience and Midterm Outcomes.

Myocardial bridging (MB) occurs when a coronary artery, commonly the left anterior descending (LAD), has an intramyocardial course. In symptomatic patients who fail medical therapy, surgical unroofing can provide symptomatic relief by improving coronary blood flow. We present a series of patients undergoing robotic totally endoscopic beating-heart MB unroofing. There were 34 patients with an LAD-MB who failed medical therapy and underwent robotic totally endoscopic, off-pump unroofing between January 2017 and October 2023. Patients were evaluated by a multidisciplinary team and underwent provocative coronary angiography to confirm hemodynamic significance. We reviewed perioperative outcomes and contacted patients for midterm follow-up, including completion of a modified Seattle Angina Questionnaire (SAQ). The mean age was 48 ± 8 years, and 56% were female patients. One patient had prior septal myectomy via sternotomy. All patients had significant dobutamine Pd/Pa reduction on preoperative coronary angiography. One patient had atrial fibrillation and underwent concomitant ablation with left atrial appendage ligation. The mean procedure time was 140 ± 69 min. All were completed totally endoscopically off-pump without intraoperative conversions. The mean MB length was 4.5 ± 1.4 cm, and the mean depth was 1.6 ± 0.9 cm. Of the patients, 76% were extubated in the operating room. The mean intensive care unit and hospital length of stay were 0.97 ± 0.58 and 1.73 ± 1.1 days, respectively. There were no mortalities or strokes. There was 1 postoperative take-back for bleeding. At midterm follow-up (19 ± 14 months), 28 patients completed the SAQ; 86% reported "much less angina" during activity compared with before surgery, and 93% reported taking no antianginal medication since surgery. In appropriate patients with hemodynamically significant LAD-MB who fail medical therapy, robotic beating-heart unroofing is possible with good outcomes. Further studies are warranted.

Myocardial infarction with non-obstructive coronary arteries in a young seropositive woman with human immunodeficiency virus: a case report and review of the literature

BackgroundElevated susceptibility to acute myocardial infarction and various cardiovascular diseases has been observed in individuals infected with the human immunodeficiency virus compared with the uninfected population, as demonstrated in numerous studies. The precise mechanism by which human immunodeficiency virus infection heightens the risk of acute myocardial infarction remains elusive. The manifestation of acute coronary syndrome in young patients with human immunodeficiency virus may deviate from the typical, displaying distinct pathophysiological and clinical characteristics. The occurrence of myocardial infarction with non-obstructive coronary arteries in young patients with human immunodeficiency virus poses diagnostic and treatment challenges.Case presentationWe present the case of a 46-year-old African woman with no traditional atherosclerotic risk factors. She was diagnosed with human immunodeficiency virus-1 infection 2 years prior to her current admission for chest pain. Her troponin levels were elevated, suggestive of acute coronary syndrome. Although coronary angiography ruled out coronary artery stenosis, it revealed mild myocardial bridging in the left anterior descending artery. Cardiac magnetic resonance imaging confirmed myocardial infarction, indicating a myocardial infarction with non-obstructive coronary arteries with an apical thrombus in the left ventricle. Following medical treatment, the patient experienced resolution of chest pain and improvement in ST-segment elevation.ConclusionsIn young female patients without traditional risk factors, human immunodeficiency virus infection is a possible etiological factor for myocardial infarction with non-obstructive coronary arteries. The likely pathophysiological pathway is superficial endothelial cell denudation as a result of chronic inflammation and immune activation.

Acute myocardial infarction or Takotsubo syndrome in a patient with stunned myocardium due to myocardial bridging? A case report of diagnostic dilemma clarified after serial workup

BackgroundMyocardial bridging is a cardiac anomaly where a segment of epicardial coronary arteries runs through the myocardium and can rarely cause MI. Takotsubo syndrome is a stress-induced cardiomyopathy that can mimic MI. Catecholamine surge during stress can contribute to Takotsubo syndrome, but whether this surge can trigger an inconspicuous myocardial bridging to manifest symptomatically remains unclear, and alternately, whether a myocardial bridge might cause worsening of Takotsubo syndrome is also a matter that needs further research.Case presentationWe report the case of a patient who initially presented with features of acute exacerbation of bronchiectasis and subsequently developed symptoms and ECG features suggestive of acute myocardial infarction. Echocardiography revealed features of takotsubo syndrome, and complete myocardial bridging was revealed via coronary angiography. The patient was managed conservatively with pharmacological treatment, and after a few days, echocardiographic features were reversed. As such, the diagnosis shifted toward Takotsubo syndrome with myocardial stunning due to co-existent myocardial bridging.ConclusionWe report a rare case of a patient with acute bronchiectasis exacerbation with features suggestive of acute myocardial infarction who had findings of Takotsubo syndrome and complete myocardial bridging. In the beginning, it was difficult to determine whether the symptoms arose due to acute MI resulting from myocardial bridging or were solely due to takotsubo syndrome because of stress from bronchiectasis. Although myocardial bridging is often overlooked as an etiology for acute MI, this case highlights the importance of expanding the differential diagnosis to myocardial bridging in the work-up for the cause of acute MI and how Takotsubo syndrome can mimic acute MI and pose a diagnostic challenge.

Two-dimensional speckle tracking echocardiography and stress computed tomography myocardial perfusion: potential for early imaging of asymptomatic patients with myocardial bridges

Aim. To evaluate the effectiveness of left ventricular (LV) peak global longitudinal strain and potential of computed tomography myocardial perfusion (CT perfusion) for the early diagnosis of asymptomatic patients with myocardial bridges (MBs).Material and methods. Forty patients were examined (20 with asymptomatic MBs in the area of the left anterior descending (LAD) artery and 20 without MBs) at the S. M. Kirov Military Medical Academy in the period from 2021 to 2023. The patients were divided into 2 equal groups consisting of 20 people (10 with MBs — the main group; 10 without MBs — the comparison group), one of which underwent speckle tracking echocardiography (STE), and the other — stress CT perfusion performed (adenosine triphosphate 160 mg/kg). The results were assessed in accordance with the 17-segment classification of LV proposed by the American Heart Association (2002).Results. When performing STE, 5 (50%) patients with MBs showed a decrease in LV local strain in the segments, the blood supply of which comes from the LAD artery and its branches, while in the comparison group — 1 (10%) (x2=5; p=0,025). When assessing the global longitudinal peak strain (GLPS), a significant difference was revealed among the study groups, amounting to -20,9±1,5% in patients with MBs and -22,1±0,9% in those without MBs (p=0,04). Using ROC analysis, the effectiveness of GLPS in prediction of asymptomatic MBs was calculated as follows: AUC=0,93 (95% confidence interval: 0,819-1,0; p=0,001), the cut-off point — -20,55% (sensitivity 80%, specificity 100%). According to CT perfusion data, impaired myocardial blood supply in the group of asymptomatic patients with MBs was noted in 6 (60%) cases, and in the comparison group — 2 (20%) (x2=9,8; p=0,002).Conclusion. Imaging of initial LV changes according to two-dimensional STE and detection of coronary circulatory disorders according to CT myocardial perfusion in asymptomatic patients with MBs makes it possible to timely suspect intramyocardial course of the coronary artery, as well as to consider further management tactics and carry out early prevention of possible cardiovascular events.

Coronary Events Following Dobutamine Stress Cardiac Magnetic Resonance Imaging in Pediatric Patients.

Dobutamine stress cardiac magnetic resonance (dsCMR) has demonstrated value in identifying patients at risk for adverse cardiovascular events in adults with coronary artery disease, but its prognostic value in younger patients is unknown. This study sought to evaluate the relationship between dsCMR results and the risk of subsequent cardiovascular events in children. Patients age < 23years who underwent dsCMR at Boston Children's Hospital were eligible for inclusion. Patients were excluded if no follow-up data were available after dsCMR or the dsCMR protocol was not completed. Data regarding the presence of inducible regional wall motion abnormalities and subsequent cardiovascular events during follow-up were analyzed. Cardiovascular events included myocardial infarction, surgical or catheter-based coronary artery intervention, and ischemic symptoms. Among 80 dsCMR studies in 64 patients with median age 5.3years (range 0.5-22.4years), 3 patients had a positive dsCMR with inducible regional wall motion abnormalities. Over a median follow-up of 7.4years (IQR 4.0-11.2), 2 of these patients underwent surgical intervention (coronary artery bypass grafting and unroofing of a myocardial bridge) and the third remained asymptomatic with no interventions. Among 61 patients with a negative dsCMR, none experienced myocardial infarction, death, or aborted sudden death. Four underwent cardiac interventions (cardiac transplantation, coronary artery bypass grafting, and unroofing) due to symptoms or catheterization findings. In pediatric patients undergoing dsCMR, wall motion abnormalities indicating inducible ischemia were uncommon. Those with a negative dsCMR were unlikely to experience an adverse cardiac event or undergo a cardiac intervention on medium-term follow-up.

Predictors of discordance between CT-derived fractional flow reserve (CT-FFR) and △CT-FFR in deep coronary myocardial bridging

ObjectiveTo compare the performance between CT-derived fractional flow reserve (CT-FFR) and ΔCT-FFR measurements in patients with deep myocardial bridging (MB) along the left anterior descending artery, and explore the potential predictors of discordance. Methods175 patients with deep MB who underwent coronary computed tomography angiography (CCTA) and CT-FFR assessment were included. Clinical, anatomical and atherosclerotic variables were compared between patients with concordant and discordant CT-FFR and ΔCT-FFR. Results30.9 % patients were discordantly classified, in which 94.4 % patients were classified as CT-FFR+/△CT-FFR-. The discordant group showed significantly higher upstream stenosis degree, distance from MB to the aorta, △CT-FFR (P 0.007, 0.009 and 0.002, respectively), and lower CT-FFR (P < 0.001). In multivariate analysis, upstream stenosis degree (P 0.023, OR 1.628, 95 % CI: 1.068–2.481) and distance from MB to the aorta (P 0.001, OR 1.04, 95 % CI: 1.016–1.064) were independent predictors for discordance between CT-FFR and ΔCT-FFR. ConclusionThe discordance between CT-FFR and ΔCT-FFR measurements underscores the challenges in clinical decision-making, necessitating tailored approaches for MB evaluation.

Prevalence of Coronary Microvascular Dysfunction and Epicardial Spasm in Patients With Angina and Myocardial Bridge

BackgroundMyocardial bridges (MB) are prevalent but not universally associated with angina. The mechanisms linking MB and angina are poorly defined. The objective of this study was to determine the prevalence of epicardial spasm, microvascular spasm, and/or endothelium-independent coronary microvascular dysfunction (CMD) in patients with MB which might explain symptoms. MethodsPatients with known MB and chest pain at the University of Chicago Medical Center between 2020-2023 were included. All patients underwent dobutamine testing with measurement of resting full-cycle ratio to determine hemodynamic significance (resting full-cycle ratio ≤0.76). Endothelium-independent CMD was defined as coronary flow reserve <2.0 or index of microvascular resistance ≥25 on adenosine testing. Microvascular spasm was defined as chest pain and electrocardiogram changes with nonischemic fractional flow reserve with acetylcholine. Epicardial spasm was defined as dynamic stenosis of >90% of the epicardial vessel or ischemic fractional flow reserve (≤0.8) with acetylcholine. ResultsA total of 30 patients (mean age, 47 ± 10 years; 60% female) with MB were studied. Endothelium-independent CMD, microvascular spasm, and epicardial spasm occurred commonly in 60%, 29%, and 37% of patients respectively, with 77% having at least one abnormality. The MB was hemodynamically significant in 47% of patients, and the prevalence of these coexisting conditions was not affected by hemodynamic significance. ConclusionsEpicardial spasm, microvascular spasm, and endothelium-independent CMD are prevalent in patients presenting with known MB and chest pain irrespective of the hemodynamic significance of the bridge. Invasive coronary function testing may play an important role in uncovering alternative explanations for angina in patients with known MB.

Myocardial ischemia caused by the synergistic effect of myocardial bridge and moderate stenosis: case report

BackgroundClinical events such as angina pectoris, acute coronary syndrome, and sudden death caused by myocardial bridge (MB) have attracted increasing attention. It is still a challenge to diagnose whether MB can cause the symptoms of patients with MB. For most MB patients, medication remains the primary treatment.Case presentationThis article reports a case of chest pain in a patient with MB in the middle segment of the left anterior descending artery (LADm) with moderate stenosis in the proximal segment (LADp). Through functional assessment, we found that neither MB nor fixed stenosis had sufficient effect on coronary blood flow to cause myocardial ischemia, but their synergistic effect resulted in myocardial ischemia. Finally, a stent was implanted in LADp and good clinical results were achieved.ConclusionsFor symptomatic patients with MB combined with fixed stenosis, functional evaluation may be necessary, which has significant guiding significance for treatment strategy selection. For asymptomatic patients, early detection of myocardial ischemia may also improve the prognosis of patients.