Benefit of ultra-high-density mapping-guided radiofrequency reablation in pulmonary vein isolation non-responders after initial cryoballoon procedure.

Aims: Symptomatic atrial arrhythmias despite complete pulmonary vein isolation (PVI) are common. The purpose was to evaluate ultra-high-density multi-electrode electroanatomical mapping-guided radiofrequency ablation (RFA) in PVI non-responders.

Methods And Results: Ultra-high-density multi-electrode electroanatomical mapping-guided RFA in consecutive symptomatic atrial fibrillation (AF) patients after initial cryoballoon PVI was performed.

Radiation Dose Reduction Using a Novel Fluoroscopy System in Patients Undergoing Diagnostic Invasive Coronary Angiography.

Background: Invasive coronary angiography (ICA) still causes a significant amount of radiation exposure for patients and operators. In February 2017, the Azurion system was introduced, a new-generation fluoroscopy image acquisition and processing system. Radiation exposure in patients undergoing ICA was assessed comparing the novel Azurion 7 F12 angiography system to its predecessor Allura Xper in a randomized manner.

The Feasibility, Tolerability, Safety, and Accuracy of Low-radiation Dynamic Computed Tomography Myocardial Perfusion Imaging With Regadenoson Compared With Single-photon Emission Computed Tomography.

Objectives: Computed tomography (CT) myocardial perfusion imaging (CT-MPI) with hyperemia induced by regadenoson was evaluated for the detection of myocardial ischemia, safety, relative radiation exposure, and patient experience compared with single-photon emission computed tomography (SPECT) imaging.

Materials And Methods: Twenty-four patients (66.5 y, 29% male) who had undergone clinically indicated SPECT imaging and provided written informed consent were included in this phase II, IRB-approved, and FDA-approved clinical trial.

In-Hospital Cost Comparison of Triple-Rule-Out Computed Tomography Angiography Versus Standard of Care in Patients With Acute Chest Pain.

Purpose: The purpose of this study was to evaluate the utilization of invasive and noninvasive tests and compare cost in patients presenting with chest pain to the emergency department (ED) who underwent either triple-rule-out computed tomography angiography (TRO-CTA) or standard of care.

Materials And Methods: We performed a retrospective single-center analysis of 2156 ED patients who presented with acute chest pain with a negative initial troponin and electrocardiogram for myocardial injury. Patient cohorts matched by patient characteristics who had undergone TRO-CTA as a primary imaging test (n=1139) or standard of care without initial CTA imaging (n=1017) were included in the study.

The stressed vascular barrier and coagulation - The impact of key glycocalyx components on in vitro clot formation.

Introduction: A functional vascular barrier controlling leukocyte recruitment into the perivascular space relies on an intact endothelial glycocalyx (EGX). Critical disease states such as sepsis or trauma can induce massive shedding of EGX components into the blood stream. Previous studies have shown that high blood levels of EGX components are correlated with bleeding in patients.

Coronary CT angiography derived plaque markers correlated with invasive instantaneous flow reserve for detecting hemodynamically significant coronary stenoses.

Purpose: The study aimed to compare morphological and anatomic plaque markers derived from coronary computed tomography angiography (cCTA) for the detection of lesion specific ischemia with invasive instantaneous wave free ratio (iFR®) as the reference standard.

Methods: In our prospective study, we enrolled patients with suspected coronary artery disease (CAD), who had undergone cCTA, using a low-dose third-generation dual-source CT and invasive coronary angiography (ICA) with iFR® measurement. Various plaque markers were assessed on cCTA.

Symptomatic arrhythmias after catheter ablation of atrioventricular nodal reentrant tachycardia (AVNRT): results from the German Ablation Registry.

Background: In atrioventricular nodal reentrant tachycardia (AVNRT), catheter ablation is considered as first-line therapy. Despite high success rates, some patients present with arrhythmia recurrence or develop other types of arrhythmias over time.

Objective: To assess the incidence of symptomatic arrhythmias after initially successful AVNRT ablation and to analyze their clinical implications in a real-world cohort.

Gender differences in the diagnostic performance of machine learning coronary CT angiography-derived fractional flow reserve -results from the MACHINE registry.

Purpose: This study investigated the impact of gender differences on the diagnostic performance of machine-learning based coronary CT angiography (cCTA)-derived fractional flow reserve (CT-FFR) for the detection of lesion-specific ischemia.

Method: Five centers enrolled 351 patients (73.5% male) with 525 vessels in the MACHINE (Machine leArning Based CT angiograpHy derIved FFR: a Multi-ceNtEr) registry.

Review of Clinical Applications for Virtual Monoenergetic Dual-Energy CT.

In this article, the authors discuss the technical background and summarize the current body of literature regarding virtual monoenergetic (VM) images derived from dual-energy CT data, which can be reconstructed between 40 and 200 keV. Substantially improved iodine attenuation at lower kiloelectron volt levels and reduced beam-hardening artifacts at higher kiloelectron volt levels have been demonstrated from all major manufacturers of dual-energy CT units. Improved contrast attenuation with VM imaging at lower kiloelectron volt levels enables better delineation and diagnostic accuracy in the detection of various vascular or oncologic abnormalities.

Influence of Coronary Calcium on Diagnostic Performance of Machine Learning CT-FFR: Results From MACHINE Registry.

Objectives: This study was conducted to investigate the influence of coronary artery calcium (CAC) score on the diagnostic performance of machine-learning-based coronary computed tomography (CT) angiography (cCTA)-derived fractional flow reserve (CT-FFR).

Background: CT-FFR is used reliably to detect lesion-specific ischemia. Novel CT-FFR algorithms using machine-learning artificial intelligence techniques perform fast and require less complex computational fluid dynamics.

Significant Radiation Dose Reduction Using a Novel Angiography Platform in Patients Undergoing Cryoballoon Pulmonary Vein Isolation.

Objectives: Cryoballoon pulmonary vein isolation (cPVI) in patients with atrial fibrillation requires fluoroscopic guidance, causing a relevant amount of radiation exposure. Strategies to reduce radiation exposure in electrophysiologic procedures and specifically cPVI are of great importance. The aim of this study was to evaluate a possible reduction of radiation dose using the novel Azurion 7 F12 x-ray system compared with its predecessor Allura FD10.

Impact of severe left ventricular outflow tract calcification on device failure and short-term mortality in patients undergoing TAVI.

Background: To investigate the impact of left ventricular outflow tract (LVOT) calcification on the incidence of device failure and mortality in patients undergoing transcatheter aortic valve implantation (TAVI).

Methods: Of 690 consecutive patients undergoing transfemoral TAVI in our center from January 2013 to December 2015, 600 presented with non-severe (NSCA) and 90 (13.0%) with severe (SCA) LVOT calcification.

Cardiac Computed Tomography for Atrial Fibrillation Patients Undergoing Ablation: Implications for the Prediction of Early Recurrence.

Objective: The objective of this study was to correlate early recurrence of atrial fibrillation (AF) after ablation with noninvasive imaging using cardiac computed tomography (CT).

Methods: CT image data of 260 patients who had undergone wide area circumferential ablation (WACA) between October 2005 and August 2010 as well as from 30 subjects in sinus rhythm without a history of AF (control group) were retrospectively analyzed. To evaluate early outcome of AF ablation, all AF patients underwent follow-up with a 30-day event monitor 3 to 4 months after ablation.

The fourth cryoballoon generation with a shorter tip to facilitate real-time pulmonary vein potential recording: Feasibility and safety results.

Introduction: Time-to-isolation (TTI) guided ablation protocols have been developed to ensure durable pulmonary vein isolation (PVI) in cryoballoon ablation (CBA). The aim was to determine the feasibility and safety of the fourth generation cryoballoon (CBG4) with a shortened tip.

Methods And Results: Consecutive patients scheduled for initial atrial fibrillation (AF) ablation were prospectively included.

Renal Sympathetic Denervation: Does Reduction of Left Ventricular Mass Improve Functional Myocardial Parameters? A Cardiovascular Magnetic Resonance Imaging Pilot Study.

Objectives: Left ventricular (LV) hypertrophy in resistant hypertensive patients is associated with a reduced intramyocardial perfusion. Renal sympathetic denervation (RDN) has been shown to reduce blood pressure (BP) and sympathetic tone. We aimed to prospectively investigate the effect of RDN on functional myocardial parameters and myocardial perfusion reserve (MPR) using cardiac magnetic resonance imaging (cMRI) in patients with resistant hypertension.

Prognostic value of CT myocardial perfusion imaging and CT-derived fractional flow reserve for major adverse cardiac events in patients with coronary artery disease.

Objectives: The purpose of this study was to analyze the prognostic value of dynamic CT perfusion imaging (CTP) and CT derived fractional flow reserve (CT-FFR) for major adverse cardiac events (MACE).

Methods: 81 patients from 4 institutions underwent coronary computed tomography angiography (CCTA) with dynamic CTP imaging and CT-FFR analysis. Patients were followed-up at 6, 12, and 18 months after imaging.

Can we rely on Danish? Real-world data on patients with nonischemic cardiomyopathy from the German Device Registry.

According to current guidelines prophylactic implantable cardioverter-defibrillator (ICD) therapy is recommended in patients with significantly impaired left ventricular systolic function. However, the recently published DANISH trial did not find a significantly lower long-term rate of death from any cause compared with usual clinical care in patients with non-ischemic cardiomyopathy. We investigated whether registry data from a multi-center 'real-life' registry on patients with non-ischemic cardiomyopathy are similar to this trial.

Coronary CT angiography-derived plaque quantification with artificial intelligence CT fractional flow reserve for the identification of lesion-specific ischemia.

Objectives: We sought to investigate the diagnostic performance of coronary CT angiography (cCTA)-derived plaque markers combined with deep machine learning-based fractional flow reserve (CT-FFR) to identify lesion-specific ischemia using invasive FFR as the reference standard.

Methods: Eighty-four patients (61 ± 10 years, 65% male) who had undergone cCTA followed by invasive FFR were included in this single-center retrospective, IRB-approved, HIPAA-compliant study. Various plaque markers were derived from cCTA using a semi-automatic software prototype and deep machine learning-based CT-FFR.

Artificial intelligence machine learning-based coronary CT fractional flow reserve (CT-FFR): Impact of iterative and filtered back projection reconstruction techniques.

Background: The influence of computed tomography (CT) reconstruction algorithms on the performance of machine-learning-based CT-derived fractional flow reserve (CT-FFR) has not been investigated. CT-FFR values and processing time of two reconstruction algorithms were compared using an on-site workstation.

Methods: CT-FFR was computed on 40 coronary CT angiography (CCTA) datasets that were reconstructed with both iterative reconstruction in image space (IRIS) and filtered back-projection (FBP) algorithms.

Fractional flow reserve derived from CCTA may have a prognostic role in myocardial bridging.

Purpose: To evaluate the feasibility of fractional flow reserve (cFFR) derivation from coronary CT angiography (CCTA) in patients with myocardial bridging (MB), its relationship with MB anatomical features, and clinical relevance.

Methods: This retrospective study included 120 patients with MB of the left anterior descending artery (LAD) and 41 controls. MB location, length, depth, muscle index, instance, and stenosis rate were measured.

Long-term symptom improvement and patient satisfaction after AV-node ablation vs. pulmonary vein isolation for symptomatic atrial fibrillation: results from the German Ablation Registry.

Background: We aimed to compare patient characteristics and outcome of patients who had either undergone pulmonary vein isolation (PVI) or AV-node ablation (AVN) to control AF-related symptoms.

Methods: From the German Ablation Registry, we analyzed data of 4444 patients (95%) who had undergone PVI and 234 patients (5%) with AVN.

Results: AVN patients were on average 10 years older than PVI patients (71 ± 10 vs.