NUMERICAL INVESTIGATION OF THERMAL TRANSPORT MECHANISMS DURING ULTRA-FAST LASER HEATING OF NANO-FILMS USING 3-D DUAL PHASE LAG (DPL) MODEL

Ultra-fast laser heating of nano-films is investigated using 3-D Dual Phase Lag heat transport equation with laser heating at different locations on the metal film. The energy absorption rate, which is used to model femtosecond laser heating, is modified to accommodate for three-dimensional laser heating. A numerical solution based on an explicit finite-difference method is employed to solve the DPL equation. The stability criterion for selecting a time step size is obtained using von Neumann eigenmode analysis, and grid function convergence tests are performed. DPL results are compared with classical diffusion and hyperbolic heat conduction models and significant differences among these three approaches are demonstrated. We also develop an implicit finite-difference scheme of Crank-Nicolson type for solving 1-D and 3-D DPL equations. The proposed numerical technique solves one equation unlike other techniques available in the literature, which split the DPL equation into a system of two equations and then apply discretization. Stability analysis is performed using a von Neumann stability analysis. In 3-D, the discretized equation is solved using delta-form Douglas and Gunn time splitting. The performance of the proposed numerical technique is compared with the numerical techniques available in the literature

Tailoring antiplatelet therapy in older patients with coronary artery disease

The older population represents a unique subset of patients due to a higher rate of comorbidities and risk factors, which can lead to a higher rate of ischemic and bleeding events. As a result, older adults are mainly underrepresented or excluded from randomized trials. Although the advancement in the percutaneous coronary intervention field with the development of new technologies, techniques, and potent antiplatelet therapy led to a reduction of ischemic risk, there is still a concern regarding bleeding hazards. Apart from the global utilization of less invasive trans-radial approach and proton pump inhibitors to reduce bleeding risk, proper tailoring of antiplatelet therapy in the older person is imperative. So far, several antiplatelet drugs have been introduced in different clinical scenarios, with dual antiplatelet therapy (combination of acetylsalicylic acid and P2Y12 inhibitor) recommended after percutaneous coronary intervention. The decision on the choice of antiplatelet drug and the DAPT duration is challenging and should be based on the relationship between ischemia and bleeding with the purpose of reducing ischemic events but not at the expense of increased bleeding complications. This is particularly important in the older population, where the evidence is obscure. The main objective of this review is to summarize the available evidence on contemporary antiplatelet therapy and different approaches of de-escalation strategies in older patients after percutaneous coronary intervention.What is the context?The older population represents a unique subset of patients due to a higher rate of comorbidities, risk factors, and unfavorable prognostic features, which can lead to a higher rate of ischemic and bleeding events. They are either excluded or underrepresented in most randomized clinical trials, which is why guidelines recommendation should be taken cautiously. Thus, the decision on the choice of antiplatelet therapy and its duration after percutaneous coronary intervention in older adults is challenging and should be tailored to a particular patient to avoid bleeding complications but not at the expense of increased ischemic events.What is new?In this review, we summarize all available evidence on contemporary antiplatelet therapy and different approaches of de-escalation strategies in older patients after percutaneous coronary intervention. In particular, several recommended approaches in patients with high bleeding risk, are thoroughly discussed in this review: De-escalation strategies with discontinuation of one antiplatelet drugDe-escalation strategy with switching between P2Y12 inhibitorsDe-escalation strategy based on dose reductionFinally, based on the current knowledge on factors contributing to high bleeding risk and the aforementioned antiplatelet modification approaches, in this review, we propose antiplatelet algorithm after percutaneous coronary intervention in older adults.What is the impact?The review provides comprehensive knowledge on antiplatelet therapy in older population and may help in tailoring antiplatelet therapy in this unique subset of patients

OCT for the Identification of Vulnerable Plaque in Acute Coronary Syndrome

AbstractAfter 2 decades of development and use in interventional cardiology research, optical coherence tomography (OCT) has now become a core intravascular imaging modality in clinical practice. Its unprecedented spatial resolution allows visualization of the key components of the atherosclerotic plaque that appear to confer “vulnerability” to rupture—namely the thickness of the fibrous cap, size of the necrotic core, and the presence of macrophages. The utility of OCT in the evaluation of plaque composition can provide insights into the pathophysiology of acute coronary syndrome and the healing that occurs thereafter. A brief summary of the principles of OCT technology and a comparison with other intravascular imaging modalities is presented. The review focuses on the current evidence for the use of OCT in identifying vulnerable plaques in acute coronary syndrome and its limitations

Pre-Eclampsia and Future Cardiovascular Risk Among Women A Review

Cardiovascular disease continues to be the leading cause of death in the western world. Due to advancements in diagnosis, prevention, and treatment, cardiovascular mortality has fallen in recent years. Previous studies have evaluated the impact of traditional risk factors such as hypercholesterolemia and smoking. However, limited studies have been conducted to evaluate sex discrepancies among patients with cardiovascular disease. Pre-eclampsia is a multisystem placentally mediated disease, which usually arises after 32 weeks of gestation and classically presents with hypertension and proteinuria. Pre-eclampsia affects 2% to 8% of all pregnancies worldwide and is often complicated by fetal growth restriction. Women with a history of pre-eclampsia are at increased risk of future cardiovascular complications. Therefore, this topic is of significance to the cardiovascular health of over 300 million women worldwide. The goal of this review is to determine the association of pre-eclampsia and future cardiovascular risk and to explore the potential management options for these high-risk women

The association between vitamin D status and clinical events in high-risk older patients with non-ST elevation acute coronary syndrome undergoing invasive management.

There is a higher incidence of vitamin D deficiency in older adults. This may play a plausible mechanistic role in the occurrence of increased adverse events after non-ST elevation acute coronary syndrome (NSTEACS). This study investigated whether total vitamin D levels at the time of presentation predicted adverse outcomes in older adults undergoing invasive management of NSTEACS. Of the 629 patients screened, 300 high-risk older adults with NSTEACS managed by an invasive strategy were recruited. Serum total 25-hydroxyvitamin D was measured at index presentation. The primary outcome was defined as 1-year composite of all-cause mortality, acute coronary syndrome (ACS), unplanned repeat revascularisation, significant bleeding or stroke. Mean age was 80.5±4.8 years (61.9% male). Median vitamin D level was 29.5nmol/L [interquartile range IQR 16.0-53.0 nmol/L] and was split equally by the median for analysis forming two groups: high (median vitamin D 53.0 nmol/L [IQR 40.0-75.0]) and low (16.0 nmol/L [11.0-23.0]). The primary outcome occurred in 76 patients (25.9%); 32 (21.9%) in the low group and 44 (29.9%) in the high group, p = 0.12. Multivariable analyses showed no significant difference in the primary composite outcome at 1 year between the low and high group of baseline serum vitamin D (Hazard Ratio 1.20 [95% Confidence Interval 0.72-2.0], p = 0.48). Serum total vitamin D, measured at the time of angiography, was not associated with adverse outcomes at one year in this high-risk older cohort of patients with NSTEACS undergoing invasive management

Vasospastic angina: a review on diagnostic approach and management

\ua9 The Author(s), 2024.Vasospastic angina (VSA) refers to chest pain experienced as a consequence of myocardial ischaemia caused by epicardial coronary spasm, a sudden narrowing of the vessels responsible for an inadequate supply of blood and oxygen. Coronary artery spasm is a heterogeneous phenomenon that can occur in patients with non-obstructive coronary arteries and obstructive coronary artery disease, with transient spasm causing chest pain and persistent spasm potentially leading to acute myocardial infarction (MI). VSA was originally described as Prinzmetal angina or variant angina, classically presenting at rest, unlike most cases of angina (though in some patients, vasospasm may be triggered by exertion, emotional, mental or physical stress), and associated with transient electrocardiographic changes (transient ST-segment elevation, depression and/or T-wave changes). Ischaemia with non-obstructive coronary arteries (INOCA) is not a benign condition, as patients are at elevated risk of cardiovascular events including acute coronary syndrome, hospitalization due to heart failure, stroke and repeat cardiovascular procedures. INOCA patients also experience impaired quality of life and associated increased healthcare costs. VSA, an endotype of INOCA, is associated with major adverse events, including sudden cardiac death, acute MI and syncope, necessitating the study of the most effective treatment options currently available. The present literature review aims to summarize current data relating to the diagnosis and management of VSA and provide details on the sequence that treatment should follow

Differences in treatment and clinical outcomes in patients aged ≥75 years compared with those aged ≤74 years following acute coronary syndromes: a prospective multicentre study

\ua9 Author(s) (or their employer(s)) 2023.Objective This study describes the differences in treatment and clinical outcomes in patients aged ≥75 years compared with those aged ≤74 years presenting with acute coronary syndrome (ACS) and undergoing invasive management. Methods A large-scale cohort study of patients with ST-elevation/non-ST-elevation myocardial infarction (MI)/unstable angina underwent coronary angiography (January 2015-December 2019). Patients were classified as older (≥75 years) and younger (≤74 years). Regression analysis was used to yield adjusted risks of mortality for older versus younger patients (adjusted for history of heart failure, hypercholesterolaemia, peripheral vascular disease, chronic obstructive pulmonary disease, ischaemic heart disease, presence of ST-elevation MI on presenting ECG, female sex and cardiogenic shock at presentation). Results In total, 11 763 patients were diagnosed with ACS, of which 39% were aged ≥75 years. Percutaneous coronary intervention was performed in fewer older patients than younger patients (81.2% vs 86.2%, p<0.001). At discharge, older patients were prescribed less secondary-prevention medications than younger patients. Median follow-up was 4.57 years. Older patients had a greater risk of in-hospital mortality than younger patients (adjusted OR (aOR) 2.12, 95% CI 1.62 to 2.78, p<0.001). Older patients diagnosed with ST-elevation MI had greater adjusted odds of dying in-hospital (aOR 2.47, 95% CI 1.79 to 3.41, p<0.001). Older age was not an independent prognostic factor of mortality at 1 year (adjusted HR (aHR) 0.95, 95% CI 0.82 to 1.09, p=0.460) and at longer term (aHR 0.98, 95% CI 0.87 to 1.10, p=0.684). Conclusions Older patients are discharged with less secondary prevention. Patients aged ≥75 years are more likely to die in-hospital than younger patients