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Coronary artery disease (CAD) is a condition where the coronary arteries, which supply blood to the heart muscle, become narrowed or blocked. The most common cause of CAD is atherosclerosis, which is a condition in which plaque builds up inside the arteries, causing them to harden and narrow. These are critical conditions due to their high prevalence, adverse impact on health and quality of life, and potential for severe complications. Early detection, prevention, and effective management are essential to mitigate their effects, which delves critically on the understanding of blood flow dynamics (hemodynamics) in these arteries. While fluid dynamics simulations incorporating the deformability of blood vessels have proven to be immensely useful in this context, their outcomes remain far from being amenable for clinical decision making in real-life medical practice because of their limitations in capturing the implications of certain key physiological features such as the stiffnesses of the artery walls and the plaque deposits formed therein. In an effort to circumvent these deficits, here we report the development and deployment of a fluid–structure interaction model that unveils the sensitive dependence of the clinically relevant hemodynamic parameters on the arterial wall and plaque stiffness, bringing in explicit quantitative assessment of the pathophysiology of arterial disease progression. Our results enable direct quantification of the time-averaged wall shear stress, offering clinical insights into the biomechanical environment and the endothelial response that are critical in the initiation and progression of atherosclerotic plaques. In addition, our results pinpoint the alterations in the fractional flow reserve due to changes in the deformability of the arterial walls and plaques, providing a functional assessment of the impact of these plaques on coronary blood flow. Our simulation platform thus helps in a comprehensive assessment of cardiovascular risk, enabling better prediction, prevention, and treatment of atherosclerosis-related conditions—a paradigm that has remained to be elusive in clinical practices thus far. [ABSTRACT FROM AUTHOR]

Aims Women with angina and non-obstructive coronary artery disease (ANOCA) have a heightened risk for cardiovascular events, and the pathophysiology for ischaemic symptoms may be related to alterations in microvascular structure and function. We examined the use of breathing-enhanced oxygenation-sensitive cardiac magnetic resonance imaging (OS-CMR) using vasoactive breathing manoeuvres to assess myocardial oxygenation in women with ANOCA. Methods and results We recruited women (aged 40–65 years) from two sites in Canada who presented to healthcare with persistent retrosternal chest pain and found to have ANOCA, or without a history of cardiovascular disease. All participants were scanned using a clinical 3T MRI scanner, and OS-CMR images were acquired over a breath hold following paced hyperventilation to measure global and regional measurements of heterogeneity. Fifty-four women with ANOCA (age: 55 ± 6.2 years) and 48 healthy controls (age: 51.2 ± 4.8 years) were recruited. There was no significant difference in volume, function, mass, or global myocardial oxygenation between the two groups [mean %Δ in signal intensity (SI): 4.9 (±7.3) vs. 4.5 (±10.1), P = 0.82]. Women with ANOCA had higher regional variations in myocardial oxygenation in circumferential [median %Δ in SI: 5.1 (2.0–7.6) vs. 2.2 (1.4–3.5), P = 0.0004] and longitudinal directions [median %Δ in SI: 11.4 (5.4–16.7) vs. 6.0 (3.0–7.0), P = 0.001], which remained present in a multivariate model. Conclusion Heterogeneous myocardial oxygenation may explain ischaemic symptoms without any associated epicardial obstructive coronary artery disease. Regional variations in myocardial oxygenation on OS-CMR could serve as an important diagnostic marker for microvascular dysfunction in women with ANOCA. [ABSTRACT FROM AUTHOR]

Objective: Rare coexistence of disease or pathology. Background: A traumatic coronary artery dissection is a rare but severe complication of chest trauma that can result in blockage of the coronary artery. The clinical symptoms can vary considerably, from asymptomatic arrhythmia to acute myocardial infarction and sudden death. This report describes a young man with coronary artery dissection following blunt chest trauma from a motorcycle accident presenting with ventricular fibrillation due to acute myocardial infarction, which was treated with percutaneous transluminal coronary angioplasty and extracorporeal membrane oxygenation. Case Report: We present a 21-year-old man with chest contusion from a motorcycle accident who experienced sudden collapse due to ventricular fibrillation and acute myocardial infarction. The patient was resuscitated with extracorporeal membrane oxygenation, and 12-lead electrocardiogram showed sinus tachycardia with a hyperacute T-wave and ST elevation in leads V2-V6. Percutaneous coronary intervention revealed dissection from the ostial to proximal portion of the left anterior descending artery, and traumatic coronary artery dissection was confirmed. He was successfully treated with percutaneous transluminal coronary angioplasty, in which a drugeluting stent was inserted to enhance blood flow in the left anterior descending artery, resulting in TIMI 2 flow restoration. After 16 days of intensive care, he was discharged and was well at a 3-month follow-up. Conclusions: This report describes a case with the rare association between blunt chest trauma and coronary artery dissection and highlights that coronary artery dissection can result in ST-elevation myocardial infarction. Extracorporeal membrane oxygenation can protect the patient's circulation for coronary angioplasty. Therefore, early detection and intensive resuscitation can prevent disastrous outcomes. [ABSTRACT FROM AUTHOR]

This article explores the potential benefits of microaxial flow pumps in treating cardiogenic shock. It compares two clinical trials on temporary mechanical circulatory support and discusses their outcomes, including patient selection criteria and device-associated complications. The article emphasizes the importance of composite recovery endpoints and the intrinsic characteristics of the microaxial flow pump in determining patient outcomes. It also highlights the importance of combining mechanical circulatory support with ventricular unloading techniques for balanced hemodynamic support. Ongoing clinical trials and the need for careful patient selection and standardized management protocols are also mentioned. [Extracted from the article]

Background: The plasma uric acid to albumin ratio (UAR) is considered as a novel indicator for Inflammation. However, the association between UAR and coronary slow flow phenomenon (CSFP) remains unclear. Methods: A total of 1328 individuals with chronic coronary syndrome (CCS) receiving coronary angiography (CAG) and found no obvious obstructive stenosis (< 40%) were included in this study. 79 individuals developed CSFP and were divided into CSFP group. The 1:2 age-matched patients with normal coronary blood flow were allocated to the control group (n = 158). The clinical characteristics, laboratory parameters including uric acid, albumin ratio, UAR and the angiographic characteristics were compared between the two groups. Results: Patients with CSFP had a higher level of uric acid (392.3 ± 85.3 vs. 273.8 ± 71.5, P < 0.001), UAR (10.7 ± 2.2 vs. 7.2 ± 1.9, P < 0.001), but a lower level of plasma albumin (36.9 ± 4.2 vs. 38.5 ± 3.6, P = 0.003). Moreover, UAR increased as the numbers of vessels involved in CSFP increased. The logistic regression analysis demonstrated that UAR was independent predictors for CSFP. The Receiver operating characteristic (ROC) curve analysis showed that when UAR was more than 7.9, the AUC was 0.883 (95% CI: 0.840–0.927, p < 0.001), with the sensitivity and specificity were 78.2% and 88.2% respectively. Conclusion: Combined uric acid with plasma albumin, UAR could serve as an independent predictor for CSFP. [ABSTRACT FROM AUTHOR]

“Slow flow” is one very important concept in modern fundamental and clinical biomedicine. Slow coronary flow is indicative of delayed filling of the terminal coronary artery vessels, occurring in the absence of significant coronary stenosis. This group patient of patients exhibits a high incidence of disability and represents a significant financial and material burden for the state and the healthcare system in general.The primary objective of our study was to examine patients with slow coronary flow.We studied the standard parameters recommended by the international health care system (electrocardiography (by Medica QRS-12, Germany), through the electrical activity of a patient’s heart by the electrical impulses (beating) of the heart; HC1(Germany); coagulogramma by Coatron M1 (Germany), troponin by AQT 90 (Germany); general blood test we used automatic human counting device HC1(Germany). Also, we investigate the original parameters (non-standard parameters, which we use in this pilot study) that we were first studied for this diagnosis and non-standard parameters.A general blood test showed that patients with slow flow had a higher blood leukocyte count than the control group, but the amount of hemoglobin was normal, the hematocrit was much higher than in the control group, and the platelet count was close to the lower limit of clinical standards.We obtained details of blood flow by coagulation situation, such as prothrombin time, prothrombin index, international normalized ratio, activated partial thromboplastin time, thrombin time, fibrinogen, and rheological properties such as index of erythrocyte aggregability, index of erythrocyte deformability, plasma viscosity, in silico blood rheological index.Blood flow can be considered as a superposition of vortices with similar frequencies and wave vectors that change after bifurcations or other obstacles in the vascular network. These factors together determine the conditions for structuring the flow of moving blood. Disruption or alteration of these factors results in slow flow. It has been found that the speed of blood flow in the coronary arteries depends on changes in the number and function of red blood cells. Slow flow is directly influenced by the aggregation and deformation of red blood cells, their number, and plasma viscosity. Consequently, the rheological status plays a crucial role in determining blood flow and its velocity. [ABSTRACT FROM AUTHOR]

This article, published in the journal Circulation, discusses the past, present, and future of coronary computed tomography angiography (CCTA) as a diagnostic tool for cardiovascular disease. The essay traces the historical milestones and technological advancements that have shaped cardiac CT, highlighting its ability to provide noninvasive assessment of coronary artery disease and other cardiovascular conditions. The article also discusses the role of CCTA in the evaluation of acute and stable chest pain, as well as its potential for risk stratification and guiding preventive treatments. The authors conclude that ongoing advancements in technology and clinical research will continue to enhance the role of cardiac CT in modern cardiology. [Extracted from the article]

The article discusses a rare congenital heart anomaly known as anomalous left anterior descending artery from the pulmonary artery (ALADCAPA) with dual left anterior descending artery (LAD). The study presents two cases of young patients with this condition, highlighting the importance of early detection and potential diagnostic challenges. Surgical intervention options are discussed, emphasizing the need to consider individual patient presentations and the risk of ischemic myocardial disease. The article also touches on the controversy surrounding surgical treatment for asymptomatic patients with ALADCAPA, underscoring the importance of timely correction to prevent adverse cardiovascular events. [Extracted from the article]

Background: For ischemic patients, left ventricular function is essential to their quality of life, and the major goal of coronary interventions is to keep the myocardium's blood supply productive. Thus, the complete cessation of blood flow to the myocardium for a prolonged duration is the obstacle to chronic total occlusion (CTO). Effective CTO coronary interventions improve the quality of life for the patient by improving LV systolic function, reducing angina, and increasing exercise capacity. Aim: This study aimed to compare the immediate changes that occur in the left ventricular systolic function in patients with CTO after successful revascularization in presence or absence of collateral circulation. Subjects and methods: This was an analytical cross-sectional study that was conducted at the Military Hospitals (Air Force, Maadi and Kobri El Koba Hospitals). Patients were recruited from the Cardiology Department from January 2023 to December 2023. Two groups were included: Group 1 included forty patients with CTO in any coronary artery more than 2.5 mm in its diameter with presence of ipsilateral or contralateral collateral circulation based on coronary angiography. Group 2 included other forty patients with CTO in any coronary artery more than 2.5 mm in its diameter with no collateral circulation based on the coronary angiography. Trans- thoracic echocardiography was done for all patients including both conventional (M-mode and 2D) and tissue Doppler strain rate studies 24 hours before PCI and two weeks after successful CTO PCI with final TIMI III flow. Results: Strain rate statistically significantly improved in group 1 compared to group 2 in terms of the septal and inferior wall segments 2 weeks after CTO opening. Conclusion: In CTO interventions, the presence of collateral circulation predicts immediate improvement in left ventricular systolic function as assessed by tissue Doppler intervention (TDI) using strain rate technique despite the lack of significant effect on conventional left ventricular systolic parameters as wall motion score index measurements. [ABSTRACT FROM AUTHOR]

Background: The fundamental pathophysiological basis of acute coronary syndrome (ACS) is the creation of an intracoronary thrombosis as a result of atherosclerotic plaque rupture and disruption of coronary blood flow (CBF). The amount of intracoronary thrombus load is related to a poor outcome among individuals with ACS. Objective: To assess the ability of CHA2DS2-VASc score to predict high pre procedural intracoronary thrombus burden among individuals with non-ST segment elevation myocardial infarction (NSTEMI) who were undergoing revascularization therapy [Percutaneous Coronary Intervention (PCI)]. Patients and Methods: This prospective study enrolled 100 patients above 18 years and admitted/referred to our hospital with acute NSTEMI. The patients underwent PCI for the evaluation of cardiac risk assessment at Cardiology Department in Benha University and Materia Teaching Hospital during the period from January 2023 to January 2024. Results: No significant differences in ischemic changes, arrhythmia and RWMA were found among groups p>0.05. CHA2DS2-VASc and Killip class were independent predictors for high thrombus burden (HTB) with p values < 0.001. Cut-off value of CHA2DS2-VASc score was > 3.5 with sensitivity of 68 %, specificity of 74%, and AUC of 0.758. Conclusion: When the cutoff value is > 3.5, CHA2DS2-VASc score is a reliable indicator of the intracoronary thrombosis load in individuals with NSTEMI receiving initial PCI. [ABSTRACT FROM AUTHOR]

Cardiovascular disease (CVD), a global health concern, particularly coronary artery disease (CAD), poses a significant threat to well-being. Seeking safer and cost-effective diagnostic alternatives to invasive coronary angiography, noninvasive coronary computed tomography angiography (CCTA) gains prominence. This study employed OpenFOAM, an open-source Computational Fluid Dynamics (CFD) software, to analyze hemodynamic parameters in coronary arteries with serial stenoses. Patient-specific three-dimensional (3D) models from CCTA images offer insights into hemodynamic changes. OpenFOAM breaks away from traditional commercial software, validated against the FDA benchmark nozzle model for reliability. Applying this refined methodology to seventeen coronary arteries across nine patients, the study evaluates parameters like fractional flow reserve computed tomography simulation (FFRCTS), fluid velocity, and wall shear stress (WSS) over time. Findings include FFRCTS values exceeding 0.8 for grade 0 stenosis and falling below 0.5 for grade 5 stenosis. Central velocity remains nearly constant for grade 1 stenosis but increases 3.4-fold for grade 5 stenosis. This research innovates by utilizing OpenFOAM, departing from previous reliance on commercial software. Combining qualitative stenosis grading with quantitative FFRCTS and velocity measurements offers a more comprehensive assessment of coronary artery conditions. The study introduces 3D renderings of wall shear stress distribution across stenosis grades, providing an intuitive visualization of hemodynamic changes for valuable insights into coronary stenosis diagnosis. [ABSTRACT FROM AUTHOR]

Coronary microvascular disease (CMD) and impaired coronary blood flow control are defects that occur early in the pathogenesis of heart failure in cardiometabolic conditions, prior to the onset of atherosclerosis. In fact, recent studies have shown that CMD is an independent predictor of cardiac morbidity and mortality in patients with obesity and metabolic disease. CMD is comprised of functional, structural, and mechanical impairments that synergize and ultimately reduce coronary blood flow in metabolic disease and in other co-morbid conditions, including transplant, autoimmune disorders, chemotherapy-induced cardiotoxicity, and remote injury-induced CMD. This review summarizes the contemporary state-of-the-field related to CMD in metabolic and these other co-morbid conditions based on mechanistic data derived mostly from preclinical small- and large-animal models in light of available clinical evidence and given the limitations of studying these mechanisms in humans. In addition, we also discuss gaps in current understanding, emerging areas of interest, and opportunities for future investigations in this field. • We summarize the contemporary literature related to coronary microvascular disease in metabolic and co-morbid conditions. • This review includes clinical relevance and the mechanistic perturbations that occur in the coronary microcirculation. • The review identifies gaps in current understanding, emerging areas of interest, and opportunities for future investigations. [ABSTRACT FROM AUTHOR]

Borderline left ventricle cases present considerable difficulties in determining the most effective surgical approaches. The evolution of approaches in the field has shifted from classical systemic pulmonary shunts to orthodox univentricular palliation and has subsequently seen the emergence of biventricular repair concepts. The concept of biventricular repair for borderline left heart conditions has developed through studies that aim to establish predictive scoring systems for identifying appropriate candidates. Despite continuous efforts, a definitive scoring system for guiding this decision is still difficult to find. There is a growing trend to provide neonatal patients with borderline ventricles with options other than univentricular palliation. Several centres have developed personalized strategies, including hybrid and staged ventricular recruitment approaches. These strategies provide sufficient time for personalized decision-making, taking into account the individual circumstances of each patient. This article presents an overview of the changing approaches to borderline left ventricular cases. It discusses the use of predictive scoring systems and emphasizes the advancements in staged strategies that improve the likelihood of successful biventricular repairs. [ABSTRACT FROM AUTHOR]

Murray's law has been viewed as a fundamental law of physiology. Relating blood flow ( Q ˙ ) to vessel diameter (D) ( Q ˙ ·∝·D3), it dictates minimum lumen area (MLA) targets for coronary bifurcation percutaneous coronary intervention (PCI). The cubic exponent (3.0), however, has long been disputed, with alternative theoretical derivations, arguing this should be closer to 2.33 (7/3). The aim of this meta-analysis was to quantify the optimum flow-diameter exponent in human and mammalian coronary arteries. We conducted a systematic review and meta-analysis of all articles quantifying an optimum flow-diameter exponent for mammalian coronary arteries within the Cochrane library, PubMed Medline, Scopus, and Embase databases on 20 March 2023. A random-effects meta-analysis was used to determine a pooled flow-diameter exponent. Risk of bias was assessed with the National Institutes of Health (NIH) quality assessment tool, funnel plots, and Egger regression. From a total of 4,772 articles, 18 were suitable for meta-analysis. Studies included data from 1,070 unique coronary trees, taken from 372 humans and 112 animals. The pooled flow diameter exponent across both epicardial and transmural arteries was 2.39 (95% confidence interval: 2.24–2.54; I2 = 99%). The pooled exponent of 2.39 showed very close agreement with the theoretical exponent of 2.33 (7/3) reported by Kassab and colleagues. This exponent may provide a more accurate description of coronary morphometric scaling in human and mammalian coronary arteries, as compared with Murray's original law. This has important implications for the assessment, diagnosis, and interventional treatment of coronary artery disease. [ABSTRACT FROM AUTHOR]

Objective: To assess the association between coronary collateral circulation and ventricular contractile function in patients with non-reperfused acute myocardial infarction. Method: A retrospective and descriptive clinical study was conducted on patients with ST-elevation myocardial infarction (STEMI) at a reference cardiovascular center, from January 2006 to December 2022. Coronary angiographies and echocardiograms were reviewed to evaluate coronary collateral circulation and ventricular function, respectively. Patients were divided into groups based on the presence of collateral circulation. Both groups were compared and mortality during the index hospitalization was analyzed. Results: Out of a total of 14,985 patients with acute coronary syndrome, 8134 (54.3%) had the diagnosis of STEMI. We excluded 12,880, leaving a total of 2105 non-reperfused STEMI patients who underwent coronary angiography, revealing lesions. There were more patients without collateral circulation: 1547 (73.5%) vs. 558 (26.5%) (p = 0.025). Patients without collateral circulation had a higher left ventricular ejection fraction (median of 47% vs. 42%; p < 0.001). Mortality in patients with collateral circulation was higher compared to those without it (11.6% vs. 9.8%; p = 0.225), but statistical significance was not reached. Conclusions: Non-reperfused STEMI patients did not show protection from collateral circulation when assessing left ventricular systolic function. We did not find a difference in mortality compared to the population without development of collateral circulation. [ABSTRACT FROM AUTHOR]

The article discusses the history of cardiac computed tomography (CT) and outlines the effect of conventional invasive coronary physiology testing. Topics include design of heart's dynamic nature and early CT scanner, conventional coronary physiology testing, and clinical studies substantiating coronary physiology testing.

BACKGROUND: Quantitative myocardial blood flow (MBF) on positron-emission tomography myocardial perfusion imaging is a measure of the overall health of the coronary circulation. The ability to adequately augment blood flow, measured by myocardial blood flow reserve (MBFR), is associated with lower major adverse cardiovascular events and all-cause mortality. The age-specific ranges of MBFR in patients without demonstrable coronary artery disease have not been well established. We aimed to determine the effect of age and sex on MBF in a cohort of patients without demonstrable coronary artery disease. Patients who underwent positron-emission tomography myocardial perfusion imaging studies from 2012 to 2022 on positron-emission tomography/computed tomography cameras were included if the summed stress score was 0, the coronary calcium score was 0, and the left ventricular ejection fraction was =50%. Those with known coronary artery disease, prior history of coronary intervention, diabetes, heart/kidney/liver transplant, cirrhosis, or chronic kidney disease stage IV+ were excluded. MBF was calculated using a net retention model (ImagenQ, Cardiovascular Imaging Technologies, Kansas City), and quantile regression models were developed to predict MBF. RESULTS: Among 2789 patients (age 59.9±13.0 years, 76.4% females), median rest MBF was 0.73 (0.60-0.91) mL/min·g, stress MBF was 1.72 (1.41-2.10) mL/min·g, and MBFR was 2.31 (1.96-2.74). Across all ages, males augmented MBF in response to vasodilator stress to a greater degree than females but achieved lower absolute stress MBF. Younger males in particular achieved a higher MBFR than their female counterparts, and this gap narrowed with increasing age. Predicted MBFR for a 20-year-old male was 3.18 and female was 2.50, while predicted MBFR for an 80-year-old male was 2.17 and female was 2.02. CONCLUSIONS:' In patients without demonstrable coronary artery disease, MBFR is higher in younger males than younger females and decreases with age in both sexes. Age- and sex-specific MBFR may be important in risk prediction and guidance for revascularization and warrant further study. [ABSTRACT FROM AUTHOR]

BACKGROUND: Reliable assessment of coronary microvascular function is essential. Techniques to measure absolute coronary blood flow are promising but need validation. The objectives of this study were: first, to validate the potential of saline infusion to generate maximum hyperemia in vivo. Second, to validate absolute coronary blood flow measured with continuous coronary thermodilution at high (40-50 mL/min) infusion speeds and asses its safety. METHODS: Fourteen closed-chest sheep underwent absolute coronary blood flow measurements with increasing saline infusion speeds at different dosages under general anesthesia. An additional 7 open-chest sheep underwent these measurements with epicardial Doppler flow probes. Coronary flows were compared with reactive hyperemia after 45 s of coronary occlusion. RESULTS: Twenty milliliters per minute of saline infusion induced a significantly lower hyperemic coronary flow (140 versus 191 mL/min; P=0.0165), lower coronary flow reserve (1.82 versus 3.21; P≤0.0001), and higher coronary resistance (655 versus 422 woods units; P=0.0053) than coronary occlusion. On the other hand, 30 mL/min of saline infusion resulted in hyperemic coronary flow (196 versus 192 mL/min; P=0.8292), coronary flow reserve (2.77 versus 3.21; P=0.1107), and coronary resistance (415 versus 422 woods units; P=0.9181) that were not different from coronary occlusion. Hyperemic coronary flow was 40.7% with 5 mL/min, 40.8% with 10 mL/min, 73.1% with 20 mL/min, 102.3% with 30 mL/min, 99.0% with 40 mL/min, and 98.0% with 50 mL/min of saline infusion when compared with postocclusive hyperemic flow. There was a significant bias toward flow overestimation (Bland-Altman: bias±SD, -73.09±30.52; 95% limits of agreement, -132.9 to -13.27) with 40 to 50 mL/min of saline. Occasionally, ischemic changes resulted in ventricular fibrillation (9.5% with 50 mL/min) at higher infusion rates. CONCLUSIONS: Continuous saline infusion of 30 mL/min but not 20 mL/min induced maximal hyperemia. Absolute coronary blood flow measured with saline infusion speeds of 40 to 50 mL/min was not accurate and not safe. [ABSTRACT FROM AUTHOR]

This study introduces a novel approach using 3D Physics-Informed Neural Networks (PINNs) for simulating blood flow in coronary arteries, integrating deep learning with fundamental physics principles. By merging physics-driven models with clinical datasets, our methodology accurately predicts fractional flow reserve (FFR), addressing challenges in noninvasive measurements. Validation against CFD simulations and invasive FFR methods demonstrates the model's accuracy and efficiency. The mean value error compared to invasive FFR was approximately 1.2% for CT209, 2.3% for CHN13, and 2.8% for artery CHN03. Compared to traditional 3D methods that struggle with boundary conditions, our 3D PINN approach provides a flexible, efficient, and physiologically sound solution. These results suggest that the 3D PINN approach yields reasonably accurate outcomes, positioning it as a reliable tool for diagnosing coronary artery conditions and advancing cardiovascular simulations. [ABSTRACT FROM AUTHOR]

Introduction: Heart failure (HF) is still one of the important causes of both mortality and recurrent hospitalization. Levosimendan is an important agent that reduces these outcomes in decompensated HF. We aimed to share the effects of levosimendan on various echocardiographic parameters and systolic and diastolic functions of the left ventricle in the early period. Methods: Twenty patients with stage IV heart failure (ischemic or non-ischemic) according to NYHA, with resting blood pressure >100 mmHg, left ventricular ejection fraction <35%, and clinically unstable despite conventional therapy were included in the study. Before starting levosimendan, left and right ventricular systolic and diastolic functions and coronary flows were examined in echocardiography. The same echocardiographic parameters were re-examined in all patients 24 hours after levosimendan treatment. Results: When we made the evaluations, it was observed that systolic functions improved in the early period after levosimendan, but it was observed that the improvement in diastolic functions did not occur in the early period. Discussion and Conclusion: Since the echocardiographic evaluation was performed only 24 hours after levosimendan, it was considered necessary to re-examine the tests after 7 days, especially to evaluate the tests evaluating diastolic functions. [ABSTRACT FROM AUTHOR]

Aims Current assessment of myocardial ischaemia from stress perfusion cardiovascular magnetic resonance (SP-CMR) largely relies on visual interpretation. This study investigated the use of high-resolution free-breathing SP-CMR with automated quantitative mapping in the diagnosis of coronary artery disease (CAD). Diagnostic performance was evaluated against invasive coronary angiography (ICA) with fractional flow reserve (FFR) measurement. Methods and results Seven hundred and three patients were recruited for SP-CMR using the research sequence at 3 Tesla. Of those receiving ICA within 6 months, 80 patients had either FFR measurement or identification of a chronic total occlusion (CTO) with inducible perfusion defects seen on SP-CMR. Myocardial blood flow (MBF) maps were automatically generated in-line on the scanner following image acquisition at hyperaemic stress and rest, allowing myocardial perfusion reserve (MPR) calculation. Seventy-five coronary vessels assessed by FFR and 28 vessels with CTO were evaluated at both segmental and coronary territory level. Coronary territory stress MBF and MPR were reduced in FFR-positive (≤0.80) regions [median stress MBF: 1.74 (0.90–2.17) mL/min/g; MPR: 1.67 (1.10–1.89)] compared with FFR-negative regions [stress MBF: 2.50 (2.15–2.95) mL/min/g; MPR 2.35 (2.06–2.54) P < 0.001 for both]. Stress MBF ≤ 1.94 mL/min/g and MPR ≤ 1.97 accurately detected FFR-positive CAD on a per-vessel basis (area under the curve: 0.85 and 0.96, respectively; P < 0.001 for both). Conclusion A novel scanner-integrated high-resolution free-breathing SP-CMR sequence with automated in-line perfusion mapping is presented which accurately detects functionally significant CAD. [ABSTRACT FROM AUTHOR]

Aims Dynamic myocardial computed tomography (CT) perfusion (DM-CTP) can, in combination with coronary CT angiography (CCTA), provide anatomical and functional evaluation of coronary artery disease (CAD). However, normal values of myocardial blood flow (MBF) are needed to identify impaired myocardial blood supply in patients with suspected CAD. We aimed to establish normal values for MBF measured using DM-CTP, to assess the effects of age and sex, and to assess regional distribution of MBF. Methods and results A total of 82 healthy individuals (46 women) aged 45–78 years with normal coronary arteries by CCTA underwent either rest and adenosine stress DM-CTP (n = 30) or adenosine-induced stress DM-CTP only (n = 52). Global and segmental MBF were assessed. Global MBF at rest and during stress were 0.93 ± 0.42 and 3.58 ± 1.14 mL/min/g, respectively. MBF was not different between the sexes (P = 0.88 at rest and P = 0.61 during stress), and no correlation was observed between MBF and age (P = 0.08 at rest and P = 0.82 during stress). Among the 16 myocardial segments, significant intersegmental differences were found (P < 0.01), which was not related to age, sex, or coronary dominance. Conclusion MBF assessed by DM-CTP in healthy individuals with normal coronary arteries displays significant intersegmental heterogeneity which does not seem to be affected by age, sex, or coronary dominance. Normal values of MBF may be helpful in the clinical evaluation of suspected myocardial ischaemia using DM-CTP. [ABSTRACT FROM AUTHOR]

This article discusses a case of papillary muscle rupture (PMR) in a 61-year-old man who was admitted with acute inferior ST-segment elevation myocardial infarction. The patient underwent coronary angiography, which revealed occlusion of multiple coronary arteries. After a stent was deployed, the patient experienced acute shortness of breath, prompting further testing with transthoracic echocardiogram (TTE) and transesophageal echocardiogram (TEE). The TEE confirmed the diagnosis of PMR, and emergency surgical intervention was performed. Unfortunately, the patient died after surgery. The article emphasizes the importance of TEE in diagnosing PMR when TTE is inadequate. [Extracted from the article]

One of the reasons of the development of pathologies causing death is hypoxia. The purposes of this study were (1) to study some physiological and biochemical mechanisms of α2-adrenoblockers, which ensure the tissue resistance increase to hypoxia; (2) to offer new drugs contributing to the increase of tissues' stability towards the hypoxic affection; and (3) to submit new medications to surpass by their anti-hypoxic activity of those already used in modern medicine and have some advantages. The reactivity of postsynaptic vascular α2-adrenoceptors was determined on the damaged spinal cord expressed by the blood pressure increase in response to intravenous administration of azepexole that selectively binds to α2-adrenoceptors. Determination of the systemic hemodynamic values and the vascular resistance to the blood flow was performed by the method with plastic microspheres of marked isotopes. pO2 in the blood and the oxygen-transporting function were determined in a sample of 0.1 ml of blood in 30, 90, and 180 min after the α2-adrenoblockers' injections. It has been found that one of the major hemodynamic effects of mesedin and beditin was an improvement in cardiac output, as well as a prolonged increase in coronary blood flow and vasodilation of the heart vessels. Some anti-hypoxic mechanisms of the studied α2-adrenoblockers are an improvement of blood oxygen-transporting function followed by tissue oxygenation and the increased level of corticosterone and resistance to hypoxia. Revealing the mechanisms of action of the postsynaptic α2-adrenoceptors suggests that mesedin and beditin are potentially effective therapeutic means for many hypoxic conditions. [ABSTRACT FROM AUTHOR]

Background: The importance of a diagnostic strategy combining coronary computed tomography angiography (CCTA) with fractional flow reserve derived from CCTA (FFRCT) for detecting myocardial ischemia is increasing. However, sensitivity and specificity alone may be insufficient to understand the efficiency characteristics of a diagnostic strategy combining CCTA and FFRCT (DSCCF). Our study aimed to evaluate the overall efficiency of DSCCF in detecting myocardial ischemia and compare it with other diagnostic strategies to determine whether evaluation by DSCCF is currently appropriate. Results: This simulation study included 1000 patients with stable chest pain and suspected myocardial ischemia. Using a decision tree analysis, assuming a diagnostic strategy of adding FFRCT to CCTA-positive patients, we calculated the following efficiency parameters of DSCCF: (1) true positive (TP), false positive (FP), net false negative (FN), and net true negative (TN) test results; (2) net sensitivity; (3) net specificity; (4) positive predictive value; (5) negative predictive value; (6) post-test probability; (7) diagnostic accuracy; (8) diagnostic odds ratio; and (9) number needed to diagnose. We also calculated the efficiency parameters of other diagnostic strategies and compared them with those of DSCCF. In the basic setting, regarding efficiency parameters (1), the number of TPs, FPs, net FNs, and net TNs were 254, 69, 46, and 631, respectively. Efficiency parameters (2)–(9) were 0.85 (95% confidence interval [CI], 0.80–0.89), 0.90 (95% CI 0.88–0.92), 0.79 (95% CI 0.74–0.83), 0.93 (95% CI 0.91–0.95), 0.07 (95% CI 0.05–0.09), 0.89 (95% CI 0.86–0.90), 50.50 (95% CI 33.83–75.37), and 1.34 (95% CI 1.24–1.48), respectively. Compared with other diagnostic strategies, DSCCF had good efficiency parameters. Moreover, the sensitivity analysis did not reveal any evidence to contradict the findings in the basic setting. Conclusions: This study demonstrated the diagnostic ability characteristics of DSCCF by assessing various efficiency parameters. Compared with other diagnostic strategies, DSCCF had good efficiency. In terms of efficiency, evaluation using DSCCF for detecting myocardial ischemia appears to be appropriate. [ABSTRACT FROM AUTHOR]

Background: The association of obesity with right ventricular function and the interplay between right heart and pulmonary circulation is incompletely understood. We evaluate the role of obesity as a determinant of right ventricular-pulmonary artery coupling (RVAC). Methods: We retrospectively studied consecutive subjects without overt cardiovascular or pulmonary disease. Subjects were stratified according to body mass index (BMI) as normal weight, overweight, or obese. A transthoracic echocardiographic study was used to assess left and right heart functional and structural parameters. RVAC was assessed using the ratio of peak systolic velocity of the tricuspid annulus to pulmonary artery systolic pressure (PASP). Results: A total of 145 subjects were enrolled with diabetes mellitus incidence higher in obese. There was no difference in left ventricular global longitudinal strain and in PASP or markers of right ventricular systolic function based on BMI. RVAC was significantly lower in the presence of obesity (normal weight: 0.52 (0.19) cm·(sec·mmHg)−1 vs. overweight: 0.47 (0.16) cm·(sec·mmHg)−1 vs. obese: 0.43 (0.14) cm·(sec·mmHg)−1, p = 0.03), even after adjustment for confounders (β: −0.085, 95% confidence interval: −0.163, −0.009, p = 0.029). Conclusions: Our findings highlight the relationship between metabolic impairment and RVAC, suggesting additional mechanisms for heart failure development observed in obese subjects. [ABSTRACT FROM AUTHOR]

Myocardial fibrosis is characterized by pathological remodeling of extracellular matrix, which is a common pathological change during the development of various cardiovascular diseases. Qi transformation dysfunction in the zang-fu organs, subtle substance accumulation, and endogenous turbid evil production lead to the occurrence of diseases. The theory of turbid blood is widely used to elucidate the pathological changes of diseases and guide the prevention and treatment. Turbid blood, as a special pathogenic factor and pathological product, plays a crucial role in the oxidative stress process of myocardial fibrosis. Qi deficiency of the heart and spleen, stagnation of turbid blood, impaired blood circulation in the heart, and the inability to maintain the oxidative-reductive system balance of myocardial cells are the root causes of disease onset. Accumulation of turbid blood, intermingled phlegm and blood stasis, blockage of heart vessels, and accumulation of metabolic waste products contribute to disease progression. Prolonged turbidity accumulation leads to cardiac enlargement, scattered mental state, and pathological remodeling of the extracellular matrix, indicating a severe disease stage. Early treatment focuses on strengthening the vital qi and spleen, reducing turbidity and recovering clarity. In the middle stage, the key is to resolve phlegm, eliminate stasis, and promote clarity while removing turbidity. In the late stage, detoxification, turbidity elimination, and restoring clarity are emphasized. By adhering to the characteristics of the pathological mechanism and using traditional Chinese medicine intervention, it is possible to suppress oxidative stress, prevent pathological remodeling of the extracellular matrix, and improve myocardial fibrosis. [ABSTRACT FROM AUTHOR]

This systematic review investigates the diagnostic and prognostic utility of coronary flow reserve (CFR) assessment through echocardiography in patients with left bundle branch block (LBBB), a condition known to complicate the clinical evaluation of coronary artery disease (CAD). The literature search was performed on PubMed, EMBASE, Web of Science, Scopus, and Google Scholar, was guided by PRISMA standards up to March 2024, and yielded six observational studies that met inclusion criteria. These studies involved a diverse population of patients with LBBB, employing echocardiographic protocols to clarify the impact of LBBB on coronary flow dynamics. The findings emphasize the importance of CFR in stratifying cardiovascular risk and guiding clinical decision‐making in patients with LBBB. Pooled results reveal that patients with LBBB and significant left anterior descending (LAD) artery stenosis exhibited a marked decrease in stress‐peak diastolic velocity (MD = ‐19.03 [‐23.58; ‐14.48] cm/s; p <.0001) and CFR (MD = ‐.60 [‐.71; ‐.50]; p <.0001), compared to those without significant LAD lesions, suggesting the efficacy of stress echocardiography CFR assessment in the identification of clinically significant CAD among the LBBB population. This review highlights the clinical relevance of echocardiography CFR assessment as a noninvasive tool for evaluating CAD and stratifying risk in the presence of LBBB and underscores the need for standardized protocols in CFR measurement. [ABSTRACT FROM AUTHOR]

We examined the effect of minimal lumen segmentation uncertainty on Fractional Flow Reserve obtained from Coronary Computed Tomography Angiography FFRCT. A total of 14 patient‐specific coronary models with different stenosis locations and degrees of severity were enrolled in this study. The optimal segmented coronary lumens were disturbed using intra ±6% and inter‐operator ±15% variations on the segmentation threshold. FFRCT was evaluated in each case by 3D‐OD CFD simulations. The findings suggest that the sensitivity of FFRCT to this type of uncertainty increases distally and with the stenosis severity. Cases with moderate or severe distal coronary lesions should undergo either exact and thorough segmentation operations or invasive FFR measurements, particularly if the FFRCT is close to the cutoff (0.80). Therefore, we conclude that it is crucial to consider the lesion's location and degree of severity when evaluating FFRCT results. [ABSTRACT FROM AUTHOR]

Salmonid fish include some of the most valued cultured fish species worldwide. Unlike most other fish, the hearts of salmonids, including Atlantic salmon and rainbow trout, have a well-developed coronary circulation. Consequently, their hearts' reliance on oxygenation through coronary arteries leaves them prone to coronary lesions, believed to precipitate myocardial ischemia. Here, we mimicked such coronary lesions by subjecting groups of juvenile rainbow trout to coronary ligation, assessing histomorphological myocardial changes associated with ischemia and scarring in the context of cardiac arrhythmias using electrocardiography (ECG). Notable ECG changes resembling myocardial ischemia-like ECG in humans, such as atrioventricular blocks and abnormal ventricular depolarization (prolonged and fragmented QRS complex), as well as repolarization (long QT interval) patterns, were observed during the acute phase of myocardial ischemia. A remarkable 100% survival rate was observed among juvenile trout subjected to coronary ligation after 24 wk. Recovery from coronary ligation occurred through adaptive ventricular remodeling, coupled with a fast cardiac revascularization response. These findings carry significant implications for understanding the mechanisms governing cardiac health in salmonid fish, a family particularly susceptible to cardiac diseases. Furthermore, our results provide valuable insights into comparative studies on the evolution, pathophysiology, and ontogeny of vertebrate cardiac repair and restoration. NEW & NOTEWORTHY Juvenile rainbow trout exhibit a remarkable capacity to recover from cardiac injury caused by myocardial ischemia. Recovery from cardiac damage occurs through adaptive ventricular remodeling, coupled with a rapid cardiac revascularization response. These findings carry significant implications for understanding the mechanisms governing cardiac health within salmonid fishes, which are particularly susceptible to cardiac diseases. [ABSTRACT FROM AUTHOR]

The article thoroughly examines the dynamics of coronary circulation, shedding light on its functionality in healthy individuals and those with various health conditions. It delves into the effects of anaesthesia, the intricacies of cardiac surgical procedures, and the complexities surrounding coronary vessels, offering valuable insights into these critical aspects of cardiovascular health.

This article explores the phenomenon of spiral wave breakup in cardiac arrhythmias. The researchers conducted studies on human and rabbit hearts using optical mapping and fluorescent indicators to observe the changes in calcium concentration and action potential duration. The goal of the research is to better understand ventricular tachycardia and ventricular fibrillation in order to improve prediction and treatment methods. The findings provide valuable insights into the mechanisms underlying these conditions. [Extracted from the article]

Numerous studies have shown that oxidative stress plays an important role in peripheral artery disease (PAD). Prior reports suggested autonomic dysfunction in PAD. We hypothesized that responses of the autonomic nervous system and coronary tone would be impaired in patients with PAD during exposure to acute hyperoxia, an oxidative stressor. In 20 patients with PAD and 16 healthy, sex- and age-matched controls, beat-by-beat heart rate (HR, from ECG) and blood pressure (BP, with Finometer) were recorded for 10 min during room air breathing and 5 min of hyperoxia. Cardiovagal baroreflex sensitivity and HR variability (HRV) were evaluated as measures of autonomic function. Transthoracic coronary echocardiography was used to assess peak coronary blood flow velocity (CBV) in the left anterior descending coronary artery. Cardiovagal baroreflex sensitivity at rest was lower in PAD than in healthy controls. Hyperoxia raised BP solely in the patients with PAD, with no change observed in healthy controls. Hyperoxia induced an increase in cardiac parasympathetic activity assessed by the high-frequency component of HRV in healthy controls but not in PAD. Indices of parasympathetic activity were lower in PAD than in healthy controls throughout the trial as well as during hyperoxia. Hyperoxia induced coronary vasoconstriction in both groups, while the coronary perfusion time fraction was lower in PAD than in healthy controls. These results suggest that the response in parasympathetic activity to hyperoxia (i.e., oxidative stress) is blunted and the coronary perfusion time is shorter in patients with PAD. NEW & NOTEWORTHY: Patients with peripheral artery disease (PAD) showed consistently lower parasympathetic activity and blunted cardiovagal baroreflex sensitivity compared with healthy individuals. Notably, hyperoxia, which normally boosts parasympathetic activity in healthy individuals, failed to induce this response in patients with PAD. These data suggest altered autonomic responses during hyperoxia in PAD. [ABSTRACT FROM AUTHOR]

Myocardial infarction refers to the ischemic necrosis of myocardium, characterized by a sharp reduction or interruption of blood flow in the coronary arteries due to the coronary artery occlusion, resulting in severe and prolonged ischemia in the corresponding myocardium and ultimately leading to ischemic necrosis of the myocardium. Given its high risk, it is considered as one of the most serious health threats today. In current clinical practice, multiple approaches have been explored to diminish myocardial oxygen consumption and alleviate symptoms, but notable success remains elusive. Accumulated clinical evidence has showed that the implantation of mesenchymal stem cell for treating myocardial infarction is both effective and safe. Nevertheless, there persists controversy and variability regarding the standardizing MSC transplantation protocols, optimizing dosage, and determining the most effective routes of administration. Addressing these remaining issues will pave the way of integration of MSCs as a feasible mainstream cardiac treatment. [ABSTRACT FROM AUTHOR]

Positron emission tomography (PET) myocardial perfusion imaging in conjunction with tracer-kinetic modeling enables the concurrent assessment of myocardial perfusion and regional myocardial blood flow (MBF) of the left ventricle in absolute terms in milliliters per gram per minute (mL/g/min). The non-invasive quantification of MBF during pharmacologically induced hyperemia, at rest, and corresponding myocardial flow reserve (MFR) opens a new avenue for the identification and characterization of classical or endogen type of coronary microvascular dysfunction (CMD) as functional substrate for microvascular angina in patients with non-obstructive coronary artery disease (CAD) and/or no CAD at all. Further, PET-MBF quantification expands the scope of conventional myocardial perfusion imaging from the identification of advanced, and flow-limiting, epicardial CAD to early stages of atherosclerosis and/or CMD. Adding MBF assessment to myocardial perfusion may also reliably unravel diffuse ischemia owing to significant left main stenosis and/or multivessel CAD, commonly confirmed by peak stress transient ischemic cavity dilation of the left ventricle during maximal vasomotor stress compared to rest on gated PET images. Owing to high spatial and contrast resolution in conjunction with photon-attenuation free myocardial perfusion PET images, PET is preferentially used for CAD detection in advanced obesity and women with pronounced breast habitus. With increasing clinical use of cardiac PET perfusion and MBF assessment, individualized, and image-guided cardiovascular treatment decisions in CAD patients is likely to ensue, while its translation into improved cardiovascular outcome remains to be investigated. [ABSTRACT FROM AUTHOR]

BACKGROUND: Coronary slow flow (CSF) by invasive coronary angiography is frequently understood to be an indicator of coronary microvascular dysfunction (CMD) in patients with ischemia with nonobstructive coronary arteries. However, the relationship between visual estimates of CSF and quantitative wire-based invasive diagnosis of CMD is uncertain. METHODS: We prospectively enrolled adults aged ≥18 years with stable ischemic heart disease who were referred for invasive coronary angiography. Individuals with ≥50% epicardial coronary artery stenosis were excluded. Invasive coronary angiography was reviewed for CSF, defined as ≥3 cardiac cycles to opacify distal vessels with contrast. Coronary function testing was performed in the left anterior descending coronary artery using bolus coronary thermodilution techniques to measure coronary flow reserve (CFR) and the index of microcirculatory resistance (IMR). Invasively determined CMD was defined as abnormal CFR (<2.5), abnormal IMR (≥25), or both. RESULTS: Among 104 participants, the median age was 61.5 years and 79% were female. The median CFR was 3.6 (interquartile range, 2.5–4.7) and the median IMR was 21 (interquartile range, 13.3–28.0). Overall, 24.0% of participants had abnormal CFR, 34.6% had abnormal IMR, and 48.1% had a final diagnosis of invasively determined CMD. CSF was present in 23 participants (22.1%). The proportions of patients with CMD (56.5% versus 45.7%; P=0.36), abnormal CFR (17.4% versus 25.9%; P=0.40), and abnormal IMR (43.5% versus 32.1%; P=0.31) were not different in patients with versus without CSF. CONCLUSIONS: Among patients with ischemia with nonobstructive coronary artery, CSF was not associated with abnormal CFR, IMR, or either abnormal CFR or IMR. CSF is not a reliable angiographic surrogate of abnormal CFR or IMR as determined by invasive, wire-based physiology testing. [ABSTRACT FROM AUTHOR]

Background There is limited evidence for the use of an intra-aortic balloon pump (IABP) in adult patients with a total cavopulmonary, or Fontan circulation. Case summary A patient in his twenties with a Fontan circulation presented with sepsis, pneumonia, and pulmonary oedema. He was born with a hypoplastic left ventricle, atrioventricular septal defect, and hypoplastic aortic arch, and a total cavopulmonary circulation had been established within his first years of life. Standard of care treatment with antibiotics, non-invasive ventilatory support, loop diuretics, and vasopressors was initiated. Due to persistent pulmonary congestion and increasing general fatigue, an IABP was placed via a femoral artery to offload the failing systemic ventricle. Secondary to IABP treatment, mean arterial pressure rose, and vasodilatory nitroprusside could be introduced. Over 4 days of IABP treatment, the patient's general condition and ventricular systolic function improved significantly. Discussion This case suggests that IABP treatment was important in the recovery of our patient with a Fontan circulation, pneumonia, and heart failure. We propose that during IABP treatment, an increase in stroke volume and a reduction in ventricular filling pressure is achieved, thereby increasing the transpulmonary pressure gradient that is central to pulmonary blood flow in Fontan patients. More definitive evidence is necessary to confirm our hypotheses. [ABSTRACT FROM AUTHOR]

This study introduces and compares computational fluid dynamics of Newtonian and non‐Newtonian blood flows in coronary arteries, with and without considering stents. Three blood flow models, including Newtonian, Carreau, and non‐Newtonian power‐law models, were simulated to investigate their effect, and the solution algorithm includes drawing the geometry, creating the desired mesh, and then simulating Newtonian and non‐Newtonian blood flow different models and comparing them with each other, is presented in the article. A Newtonian fluid model has been commonly used in the simulation of blood flow, whereas blood has non‐Newtonian properties due to the nature of a solution containing suspended particles. The goal of this research is to investigate the differences between the models built with Newtonian and non‐Newtonian fluid assumptions. In addition, a stent was designed and the effect of the stent on blood flow parameters was investigated for all three flow models, including Newtonian, Carreau, and non‐Newtonian power‐law models. Stents are medical devices that can be placed in arteries to open up blood flow in a blocked vessel. Stents can affect the wall shear stress. Knowing the slight deformation of the shear stress makes the importance of stent implantation and also helps to optimize the design of the intravascular stent, which can affect the occlusion of the vessels. The distribution of the velocity, pressure, and wall shear stress in all blood flow models with and without considering the effect of stents have been investigated and finally compared. Therefore, in general, the innovation of this article is to find the effect of implanted stents on blood flow parameters with different blood flow models, both Newtonian and non‐Newtonian. A comparison of Newtonian and non‐Newtonian flows showed that in the case of the Carreau non‐Newtonian model, the wall shear stress was higher. In addition, in the results of the geometric model with a stent effect compared to the geometric model without a stent effect, it is evident that there was a higher velocity and wall shear stress. [ABSTRACT FROM AUTHOR]

We examined the effect of minimal lumen segmentation uncertainty on Fractional Flow Reserve obtained from Coronary Computed Tomography Angiography FFRCT. A total of 14 patient‐specific coronary models with different stenosis locations and degrees of severity were enrolled in this study. The optimal segmented coronary lumens were disturbed using intra ±6% and inter‐operator ±15% variations on the segmentation threshold. FFRCT was evaluated in each case by 3D‐OD CFD simulations. The findings suggest that the sensitivity of FFRCT to this type of uncertainty increases distally and with the stenosis severity. Cases with moderate or severe distal coronary lesions should undergo either exact and thorough segmentation operations or invasive FFR measurements, particularly if the FFRCT is close to the cutoff (0.80). Therefore, we conclude that it is crucial to consider the lesion's location and degree of severity when evaluating FFRCT results. [ABSTRACT FROM AUTHOR]

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Coronary artery disease (CAD) is one of the main causes of death in the world. Functional indices such as fractional flow reserve (FFR), coronary flow reserve (CFR) and instantaneous wave-free ratio (iFR) are used to estimate the severity of CAD. Approximately 30–50% of patients have residual myocardial ischaemia even after formally successful percutaneous coronary intervention (PCI). Myocardial perfusion impairment is one of the main factors responsible for recurrence. We propose a novel 1D model of coronary hemodynamics that takes into account myocardial contraction, stenoses and impaired microcirculation. It uses non-invasively acquired data. The model is able to simulate FFR and iFR with a mean relative error of 3% and a standard mean deviation of 0.04. We find that healthy FFR and iFR values in the short and long term do not always correspond to healthy CFR values and recovery of coronary blood flow. We also show that PCI of stenosis also improves hemodynamic indices in adjacent stenosed vessels, with a more pronounced effect in the long term. [ABSTRACT FROM AUTHOR]

The article focuses on the impact of heterogeneous plaque deposition on computed tomography-derived fractional flow reserve (FFRCT) in coronary artery disease. Topics include the analysis of plaque components and their relationship to lumen volume, the effect of low-attenuation plaque and calcified plaque on hemodynamics, and how computational fluid dynamics can be affected by artifacts from calcified plaque, leading to overestimation of FFRCT.

The article explores the sexual dimorphism in the susceptibility to ischemic heart disease induced by chronic psychological stress. The study conducted on male and female rats subjected to chronic restraint stress (CRS) reveals that sex-dependent mediators of chronic psychological stress response shape the myocardial microenvironment and cardiac cell tolerance to ischemia-reperfusion injury (IRI). The findings suggest that sex differences in cardiovascular reactivity to mental stress may be influenced by hormonal fluctuations and systemic inflammatory responses. The study highlights the need for targeted interventions to address the specific myocardial needs of stressed fertile women. [Extracted from the article]

Coronary microvascular disease (CMD) is a condition that affects the small blood vessels in the heart and can lead to reduced blood flow and regional ischemia. Unlike coronary artery disease (CAD), CMD does not involve the development of atheroma. While traditional risk factors for CAD, such as dyslipidemia and arterial hypertension, have been associated with obstructive CAD caused by atherosclerosis, a study found no association between CMD and these risk factors. However, diabetes mellitus is recognized as a risk factor for CMD. Microvascular changes in other organs, such as the retinal arteries and kidneys, have also been associated with traditional cardiovascular risk factors. Sex hormones may play a role in CMD, as well as microvascular disease in other organs, but more research is needed to understand the mechanisms involved. Overall, our understanding of CMD is still limited, and further studies are needed to determine the effects of traditional risk factors and the underlying pathophysiological mechanisms. [Extracted from the article]

Shone's syndrome (SS) is a rare congenital cardiac anomaly characterized by a spectrum of developmental abnormalities. It predominantly presents as consisting of a variety of left ventricular inflow and outflow tract lesions, with inflow tract lesions typically including parachute mitral valve and supravalvular mitral ring. However, reports of SS involving double‐orifice mitral valve are scarce. [ABSTRACT FROM AUTHOR]