Coronary Artery Anomaly in Takotsubo Cardiomyopathy: Cause or Innocent Bystander?

Case Report and Literature Review of an Anomalous Course of the Left Main Coronary Artery (LMCA) Arising From the Right Sinus of Valsalva (RSV) Presenting as Takotsubo Cardiomyopathy

Takotsubo cardiomyopathy (TC) mimics myocardial infarction with symptoms like chest pain, electrocardiogram (EKG) changes, and elevated troponin levels, although it typically features normal coronary arteries upon angiography. While often asymptomatic, coronary artery anomalies (CAAs) can cause intermittent vasospasm and endothelial dysfunction, potentially inducing TC. We report the case of a 74-year-old female with a history of hypertension, hyperlipidemia, and peripheral artery disease, who presented with sudden onset chest pain. Initial EKG and elevated troponin suggested myocardial infarction. However, coronary angiography revealed an anomalous left main coronary artery (LMCA) originating from the right coronary artery (RCA), with no significant stenosis. Subsequent transthoracic echocardiography indicated TC, with the left ventricular ejection fraction improving from 35-40% to 60-65% within days. Cardiac computed tomography angiography (CCTA) revealed that the anomalous LMCA originated from the common trunk at the right sinus of Valsalva (RSV), which further continued as a large, dominant RCA. The LMCA branched into a small to moderate left anterior descending artery (LAD) and a non-dominant left circumflex artery (LCx). The LMCA followed a prepulmonic/anterior course, while the LCx took an interarterial course between the aorta and pulmonary artery. The patient was referred for further surgical evaluation. We conclude that the CAA was an incidental finding and was not related to underlying TC. Although rare, this case suggests a possible correlation between CAAs and a predisposition to stress-induced cardiomyopathy, warranting further investigation.

Application of Patient-Specific Computational Fluid Dynamics in Anomalous Aortic Origin of Coronary Artery: A Systematic Review

Anomalous aortic origin of a coronary artery (AAOCA) is a rare congenital heart condition with fixed and dynamic stenotic elements, potentially causing ischemia. Invasive coronary angiography under stress is the established method for assessing hemodynamics in AAOCA, yet it is costly, technically intricate, and uncomfortable. Computational fluid dynamics (CFD) simulations offer a noninvasive alternative for patient-specific hemodynamic analysis in AAOCA. This systematic review examines the role of CFD simulations in AAOCA, encompassing patient-specific modeling, noninvasive imaging-based boundary conditions, and flow characteristics. Screening articles using AAOCA and CFD-related terms prior to February 2023 yielded 19 publications, covering 370 patients. Over the past four years, 12 (63%) publications (259 patients) employed dedicated CFD models, whereas 7 (37%) publications (111 patients) used general-purpose CFD models. Dedicated CFD models were validated for fixed stenosis but lacked dynamic component representation. General-purpose CFD models exhibited variability and limitations, with fluid-solid interaction models showing promise. Interest in CFD modeling of AAOCA has surged recently, mainly utilizing dedicated models. However, these models inadequately replicate hemodynamics, necessitating novel CFD approaches to accurately simulate pathophysiological changes in AAOCA under stress conditions.

Anomalous left anterior descending coronary artery arising from the right coronary artery: a case report

Congenital anomalous coronary artery origins are rare, with a prevalence of 0.24-1.6%. Common configurations include left circumflex arising from the right coronary (RCA), left main coronary arising from the right coronary sinus and independent ostia for the left anterior descending (LAD) and left circumflex. One rare configuration that is not well described is the LAD arising from the RCA. A 68-year-old patient presented with non-ST elevation myocardial infarction, underwent coronary artery bypass grafting and was found to have a patent LAD arising from the RCA. In patients presenting with coronary artery disease and anomalous coronary anatomy, careful preoperative planning and intraoperative attention to patient anatomy is essential in identifying high-risk coronary anomalies and providing the correct and optimal treatments for these patients.

Takotsubo Syndrome: Translational Implications and Pathomechanisms

Takotsubo syndrome (TTS) is identified as an acute severe ventricular systolic dysfunction, which is usually characterized by reversible and transient akinesia of walls of the ventricle in the absence of a significant obstructive coronary artery disease (CAD). Patients present with chest pain, ST-segment elevation or ischemia signs on ECG and increased troponin, similar to myocardial infarction. Currently, the known mechanisms associated with the development of TTS include elevated levels of circulating plasma catecholamines and their metabolites, coronary microvascular dysfunction, sympathetic hyperexcitability, inflammation, estrogen deficiency, spasm of the epicardial coronary vessels, genetic predisposition and thyroidal dysfunction. However, the real etiologic link remains unclear and seems to be multifactorial. Currently, the elusive pathogenesis of TTS and the lack of optimal treatment leads to the necessity of the application of experimental models or platforms for studying TTS. Excessive catecholamines can cause weakened ventricular wall motion at the apex and increased basal motion due to the apicobasal adrenoceptor gradient. The use of beta-blockers does not seem to impact the outcome of TTS patients, suggesting that signaling other than the beta-adrenoceptor-associated pathway is also involved and that the pathogenesis may be more complex than it was expected. Herein, we review the pathophysiological mechanisms related to TTS; preclinical TTS models and platforms such as animal models, human-induced pluripotent stem cell-derived cardiomyocyte (hiPSC-CM) models and their usefulness for TTS studies, including exploring and improving the understanding of the pathomechanism of the disease. This might be helpful to provide novel insights on the exact pathophysiological mechanisms and may offer more information for experimental and clinical research on TTS.

[Takotsubo syndrome (stress-induced cardiomyopathy)]

The article presents published and own data about Takotsubo syndrome, a relatively rare heart disease that is similar to acute coronary syndrome, but without significant damage of coronary arteries. The leading pathogenetic factor is the catecholamine-induced stress damage of myocardium with involvement of microvessels. There is a certain underestimation of Takotsubo syndrome by both clinicians and pathologists, so some cases of Takotsubo syndrome are misdiagnosed as acute coronary syndrome. Morphological manifestations of Takotsubo syndrome are characterized by mucoid edema of interstitial myocardial tissue, round-cell infiltration of stroma and focal damage of cardiomyocytes.

Hemodynamic Relevance of Anomalous Coronary Arteries Originating From the Opposite Sinus of Valsalva-In Search of the Evidence

Coronary artery anomalies (CAA) represent a heterogeneous group of congenital disorders of the arterial coronary circulation, defined by an anomalous origin of the coronary ostium and/or vessel course. Of particular interest are anomalous coronary arteries originating from the opposite sinus of Valsalva (ACAOS). The interarterial variants (with the anomalous vessel situated between the great arteries) are historically called "malignant," based on an anticipated higher risk for myocardial ischemia and sudden cardiac death (SCD), especially affecting young patients during strenuous physical activity. However, the interarterial course itself may not be the predominant cause of ischemia, but rather represents a surrogate for other ischemia-associated anatomical high-risk features. As the exact pathophysiology of ACAOS is not well-understood, there is a lack of evidence-based guidelines addressing optimal diagnostic work-up, downstream testing, sports counseling, and therapeutic options in patients with ACAOS. Therefore, treating physicians are often left with uncertainty regarding the clinical management of affected patients. This review focuses on the pathophysiologic consequences of ACAOS on myocardial ischemia and discusses the concept of the interplay between fixed and dynamic coronary stenosis. Further, we discuss the advantages and limitations of the different diagnostic modalities and give an outlook by highlighting the gaps of knowledge in the assessment of such anomalies.