coronary and Kv

Suxiao Jiuxin Pill (SJP) is a well-known traditional Chinese medicine drug used to manage heart diseases. This study aimed at determining the pharmacological effects of SJP in acute myocardial infarction (AMI), and the molecular pathways its active compounds target to induce coronary artery vasorelaxation. Using the AMI rat model, SJP improved cardiac function and elevated ST segment. LC-MS and GC-MS detected twenty-eight non-volatile compounds and eleven volatile compounds in sera from SJP-treated rats. Network pharmacology analysis revealed eNOS and PTGS2 as the key drug targets...

Hutchinson-Gilford progeria syndrome (HGPS) is an extremely rare genetic disease caused by expression of progerin, a lamin A variant that is also expressed at low levels in non-HGPS individuals. Although HGPS patients die predominantly from myocardial infarction and stroke, the mechanisms that provoke pathological alterations in the coronary and cerebral arteries in HGPS remain ill defined. Here, we assessed vascular function in the coronary arteries (CorAs) and carotid arteries (CarAs) of progerin-expressing LmnaG609G/G609G mice (G609G), both in resting conditions and after hypoxic stimulus...

PURPOSE: The aim of this study was to assess the effect of temporal resolution on subjective and objective image quality of coronary computed tomography angiography (CCTA) in the ultra-high-resolution (UHR) mode with dual-source photon-counting detector (PCD) CT. MATERIALS AND METHODS: This retrospective, institutional review board-approved study evaluated 30 patients (9 women; mean age, 80 ± 10 years) undergoing UHR CCTA with a clinical dual-source PCD-CT scanner...

OBJECTIVES: In cardiac transplant recipients, non-invasive allograft surveillance for identifying patients at risk for graft failure remains challenging. The fat attenuation index (FAI) of the perivascular adipose tissue in coronary computed tomography angiography (CCTA) predicts outcomes in coronary artery disease in non-transplanted hearts; however, it has not been evaluated in cardiac transplant patients. METHODS: We followed 39 cardiac transplant patients with two or more CCTAs obtained between 2010 and 2021...

BACKGROUND: Small coronary arteries containing stents pose a challenge in CT imaging due to metal-induced blooming artifact. High spatial resolution imaging capability is as the presence of highly attenuating materials limits noninvasive assessment of luminal patency. PURPOSE: The purpose of this study was to quantify the effective lumen diameter within coronary stents using a clinical photon-counting-detector (PCD) CT in concert with a convolutional neural network (CNN) denoising algorithm, compared to an energy-integrating-detector (EID) CT system...

BACKGROUND: Coronary computed tomography angiography (CCTA) is the preferred non-invasive examination method for coronary heart disease. However, the radiation from computed tomography has become a concern since public awareness of radiation hazards continue to increase. AIM: To explore the value of multiple dose reduction techniques for CCTA. METHODS: Consecutive normal and overweight patients were prospectively divided into two groups: Group A1 , patients who received multiple dose reduction scans ( n = 82); and group A2 , patients who received conventional scans ( n = 39)...

We previously reported that exercise training drives enhanced agonist-stimulated hydrogen peroxide (H2 O2 ) levels and restores endothelium-dependent dilation via an increased reliance on H2 O2 in arterioles isolated from ischemic porcine hearts. In this study, we tested the hypothesis that exercise training would correct impaired H2 O2 -mediated dilation in coronary arterioles isolated from ischemic myocardium through increases in protein kinase G (PKG) and protein kinase A (PKA) activation and subsequent colocalization with sarcolemmal K+ channels...

OBJECTIVES: The aim of this study was to evaluate the high-helical pitch, multienergy (ME) scanning mode of a clinical dual-source photon-counting detector (PCD) computed tomography (CT) and the benefit of virtual monoenergetic images (VMIs) for low-contrast-dose coronary CT angiography (CTA). MATERIALS AND METHODS: High-pitch (3.2) ME coronary CTA was performed in PCD-CT in 27 patients using low contrast dose (30 mL of iohexol 350 mg/mL) and in 26 patients at routine contrast dose (60 mL)...

BACKGROUND: The unique tissue selectivity of pulsed field ablation (PFA) allows for minimizing collateral damage to the nerves/esophagus. However, the safety profile of epicardial PFA on coronary arteries (CAs) has not been well defined. OBJECTIVES: This study sought to evaluate the effect of epicardial PFA directly on CAs in a swine model. METHODS: In 4 swine, an 8-F linear quadripolar PFA catheter (FARAPULSE Inc) was introduced into the pericardial space via a subxiphoid puncture...

PURPOSE: To systematically assess the radiation dose reduction potential of coronary artery calcium (CAC) assessments with photon-counting computed tomography (PCCT) by changing the tube potential for different patient sizes with a dynamic phantom. METHODS: A hollow artery, containing three calcifications of different densities, was translated at velocities corresponding to 0, < 60, 60-75, and > 75 beats per minute within an anthropomorphic phantom...

In 2011, the International Commission on Radiological Protection (ICRP) recommended a significant reduction in the lens-equivalent radiation dose limit, thus from an average of 150 to 20 mSv/year over 5 years. In recent years, the occupational dose has been rising with the increased sophistication of interventional radiology (IVR); management of IVR staff radiation doses has become more important, making real-time radiation monitoring of such staff desirable. Recently, the i3 real-time occupational exposure monitoring system (based on RaySafeTM ) has replaced the conventional i2 system...

Pericoronary adipose tissue(PCAT) is the fat deposit surrounding coronary arteries. Although PCATis part of the largerepicardial adipose tissue (EAT) depot, it has different pathophysiological features and roles in the atherosclerosis process.While EAT evaluation has been studied for years, PCAT evaluationis a relatively new concept. PCAT, especially the mean attenuationderived from CT imagesmay be used to evaluate the inflammatory status of coronary arteries non-invasively.The most commonly used measure, PCATMA , is the mean attenuation of adipose tissue of 3 mm thickness around the proximal RCA with a length of 40 mm...

BACKGROUND: Pulsed field ablation (PFA) has recently been shown to penetrate ischemic scar, but details on its efficacy, risk of arrhythmias, and imaging insights are lacking. In a porcine model of myocardial scar, we studied the ability of ventricular PFA to penetrate scarred tissue, induce ventricular arrhythmias, and assess the influence of QRS gating during pulse delivery. METHODS: Of a total of 6 swine, 5 underwent coronary occlusion and 1 underwent radiofrequency ablation to create infarct scar and iatrogenic scar models, respectively...

OBJECTIVE: The study investigated the accuracy of coronary artery calcium scores (CACS) and the potential for reducing radiation dose using non-gated low-dose non-contrast chest computed tomography (CT) scanning with tin filtration for one-stop screening of the lungs and heart. METHODS: A prospective study was conducted,193 Patients received two scans for determining CACS, including an ECG-gated CT at 120 kV (ECG-gated CT), followed by a non-gated low-dose chest CT using 100 kV with tin filtration (non-gated Sn100 kV-LDCT)...

BACKGROUND: Unoptimized coronary CT angiography (CTA) exams typically result in a highly variable arterial enhancement (HUa ) across patients. This study aimed at harmonizing arterial enhancement by implementing a patient-, contrast- and kV-tailored injection protocol. METHODS: First, the optimal body size metric to predict HUa was identified by retrospectively analysing images of 76 patients, acquired with 70 ml contrast media (G1). Second, using phantom experiments, correction factors for the effect of kV and contrast concentration on HUa were determined...

We investigated the effect of asenapine, a commonly used atypical antipsychotic, on voltage-dependent K+ (Kv) channels in rabbit coronary artery smooth muscle cells. Asenapine inhibited the Kv current in a concentration-dependent manner, with an half-inhibitory concentration (IC50 ) value of 8.59 ± 2.25 μM and Hill coefficient of 0.64 ± 0.06. Although asenapine did not affect the steady-state activation curve of Kv channels, it shifted the voltage dependence of the steady-state inactivation curve toward a more negative potential...

Objective: Imaged scan length (z-axis coverage) is a simple parameter that can reduce CT dose without compromising image quality. In CT coronary angiography (CTCA), z-axis coverage may be planned using non-contrast calcium score scan (CaCS) to identify the relevant coronary anatomy. However, standardised Agatston CaCS is acquired at 120 kV which adds a relatively high contribution to total study dose and CaCS is no longer routinely recommended in UK guidelines. We evaluate an ultra-low dose unenhanced planning scan on CTCA scan length and effective radiation dose...

Fesoterodine, an antimuscarinic drug, is widely used to treat overactive bladder syndrome. However, there is little information about its effects on vascular K+ channels. In this study, voltage-dependent K+ (Kv) channel inhibition by fesoterodine was investigated using the patch-clamp technique in rabbit coronary artery. In whole-cell patches, the addition of fesoterodine to the bath inhibited the Kv currents in a concentration-dependent manner, with an IC50 value of 3.19 ± 0.91 μM and a Hill coefficient of 0...

Background: Idiopathic ventricular fibrillation (VF) is a diagnosis of exclusion made in patients who experience VF without an attributable cause. Pathogenic variants of the ACTN2 gene encoding the sarcomeric protein alpha-actinin-2 are known to cause hypertrophic and dilated cardiomyopathy. We show that ACTN2 variants may also be associated with malignant arrhythmias in the absence of overt structural heart disease. Case summary: A 48-year-old female presented with cardiac arrest due to VF without any history of cardiovascular disease or family history of sudden cardiac death...

We investigated the effect of the acetylcholine muscarinic receptor inhibitor benztropine on voltage-dependent K+ (Kv) channels in rabbit coronary arterial smooth muscle cells. Benztropine inhibited Kv currents in a concentration-dependent manner, with an apparent IC50 value of 6.11 ± 0.80 μM and Hill coefficient of 0.62 ± 0.03. Benztropine shifted the steady-state activation curves toward a more positive potential, and the steady-state inactivation curves toward a more negative potential, suggesting that benztropine inhibited Kv channels by affecting the channel voltage sensor...