Optimization of Tl Dosage in a Simultaneous Acquisition Rest Tc/Stress Tl Dual-Isotope Myocardial Perfusion Single-Photon Emission Computed Tomography with Semiconductor Gamma Camera.

: The use of Tl in myocardial perfusion single-photon emission computed tomography (SPECT) is predominantly not recommended because of the higher radiation exposure of Tl compared to Tc agent. However, the advent of new gamma cameras with semiconductor detectors has made it possible to reduce the Tl dose and lower radiation exposure. In our hospital, the dose of Tl is adjusted according to the patient's body mass index (BMI), with 50 MBq for BMI<25 and 74 MBq for BMI≥25.

Hepatic steatosis evidenced by computed tomography in patients undergoing primary percutaneous coronary intervention for acute myocardial infarction.

Background: Non-alcoholic fatty liver disease (NAFLD) and acute myocardial infarction (AMI) have common pathological links. This study investigates the prognostic impact of NAFLD assessed as hepatic steatosis (HS) by computed tomography (CT) in AMI patients and explores the mechanistic role of NAFLD in cardiovascular (CV) events using coronary angioscopy (CAS).

Methods: We retrospectively examined 342 AMI patients who underwent CT followed by primary percutaneous coronary intervention (PCI) between January 2014 and December 2019.

Relationship Among Coronary Artery Calcium Score, Myocardial Perfusion SPECT and Risk Stratification of Coronary Artery Disease.

Since Agatston et al. first reported quantification of the coronary artery calcification score (CACS) in 1990, discussion of its clinical significance and use in diagnostic management has continued. Recent papers have reported the relationship between CACS and myocardial perfusion single photon emission computed tomography (SPECT: MPS) and its combined diagnostic value.

Optimal Protocol of Myocardial Perfusion Imaging for Reduction of Radiation Exposure.

The Japanese Circulation Society (JCS) 2021 guideline on radiation safety in cardiology was updated based on the eight best practices for myocardial perfusion single-photon emission computed tomography myocardial perfusion imaging (SPECT-MPI), which was determined by panels of international atomic energy agency (IAEA) nuclear cardiology protocols cross-sectional study (INCAPS). Although the guideline recommends to avoid too much Tl or Tl/Tc dual-isotope protocol, the utilization rate of Tl for SPECT-MPI in Japan is considerably high compared to other countries. In Japan, protocols using Tc should be appropriately promoted based on the guideline to reduce radiation exposure in SPECT-MPI.

Prognostic risk stratification based on left ventricular mechanical dyssynchrony in patients at low or intermediate risk of major cardiac events using the J-ACCESS risk model.

There have been no reports on prognostic prediction and risk stratification based on stress phase bandwidth (SPBW), or a left ventricular (LV) mechanical dyssynchrony index, in patients with known or suspected stable coronary artery disease (CAD) at low or intermediate risk of major cardiac events (MCEs) using the J-ACCESS risk model. We retrospectively investigated 4,996 consecutive patients with known or suspected CAD who underwent rest Tl and stress Tc-tetrofosmin electrocardiogram (ECG)-gated single-photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) and followed up for 3 years to confirm their prognosis. MCE risk over 3 years was estimated using an equation based on that used in the J-ACCESS study.

Clinical Utility of a Slow Tl Washout Rate in the Detection of Multi-Vessel Coronary Artery Disease Using a Simultaneous Acquisition Rest Tc/Stress Tl Protocol and a Semiconducting Gamma Camera.

Background: The diagnostic accuracy of stress myocardial perfusion single-photon emission computed tomography (SPECT) to detect coronary artery disease (CAD) is reduced by the balanced reduction of myocardial perfusion in patients with multi-vessel or left main trunk CAD (multi-vessel group). This study investigated the diagnostic performance of a simultaneous acquisition rest Tc/stress Tl dual-isotope protocol for myocardial perfusion SPECT (MPS) in a multi-vessel group by examining the assessment of a slow Tl washout rate (WR) finding in comparison to the accuracy of perfusion assessments.

Methods and results: This study enrolled 91 patients who had undergone angiography within 3 months after MPS.

Prognostic value of the normalization of left ventricular mechanical dyssynchrony after revascularization in patients with coronary artery disease.

There are no reports indicating a prognostic difference based on normalization of left ventricular (LV) mechanical dyssynchrony after revascularization in patients with coronary artery disease (CAD). We retrospectively investigated 596 patients who underwent rest Tl and stress Tc-tetrofosmin electrocardiogram-gated single-photon emission computed tomography (SPECT) myocardial perfusion imaging. All patients had significant stenosis with ≥ 75% narrowing of the coronary arterial diameter detected by coronary angiography performed after confirmation of ≥ 5% ischemia by the SPECT.

Coronary artery calcium score: Current status of clinical application and how to handle the results.

The clinical significance of the coronary artery calcium score (CACS) has been discussed since Agatston et al. first reported its utility in 1990. CACS is less invasive and less expensive than contrast-enhanced coronary computed tomography (CT) angiography.

Prognostic Significance of Left Ventricular Dyssynchrony Assessed with Nuclear Cardiology for the Prediction of Major Cardiac Events after Revascularization.

Objective This retrospective study was aimed at determining whether or not stress phase bandwidth (SPBW), a left ventricular (LV) mechanical dyssynchrony index, predicts major cardiac events (MCEs) and stratifies the risk of those in patients with coronary artery disease (CAD) who undergo revascularization. Methods Patients were followed up to confirm the prognosis for at least one year. The SPBW was calculated by a phase analysis using the Heart Risk View-F software program.

Comprehensive assessment of left atrial and ventricular remodeling in paroxysmal atrial fibrillation by the cardiovascular magnetic resonance myocardial extracellular volume fraction and feature tracking strain.

Atrial fibrillation (AF) is a progressive disease that starts with structural or functional changes in the left atrium and left ventricle, and evolves from paroxysmal toward sustained forms. Early detection of structural or functional changes in the left atrium and left ventricle in the paroxysmal stage could be useful for identifying a higher risk of progression to persistent AF and future cardio-cerebrovascular events. The aim of this study was to test the hypothesis that the feature tracking (FT) left atrial (LA) strain and left ventricular (LV) extracellular volume fraction (ECV) derived from cardiovascular magnetic resonance (CMR) could detect early changes in remodeling of the left atrium and ventricle in the paroxysmal AF (PAF) stage.

Effect of Coronary Computed Tomography Angiography-Derived Fractional Flow Reserve on Physicians' Clinical Behavior - Differences Between Sites With and Without Appropriate Use Criteria as Designated by the Japanese Reimbursement System.

Coronary computed tomography angiography (CCTA)-derived fractional flow reserve (FFR) is an established tool for identifying lesion-specific ischemia that is now approved for use by the Japanese insurance system. However, current clinical reimbursement is strictly limited to institutions with designated appropriate use criteria (AUC). This study assessed differences in physicians' behavior (e.

Incremental Predictive Value of Coronary Calcium Score in Risk Stratification of Coronary Revascularization in Patients With Normal or Mild Ischemia Using Nuclear Myocardial Perfusion Single Photon Emission Computed Tomography.

Background: The incremental predictive value of the coronary artery calcium score (CACS) for risk stratification of coronary revascularization in patients with normal or mildly abnormal nuclear myocardial perfusion single photon emission computed tomography (MPS) scores is unknown.

Methods and results: We analyzed 528 patients in whom CACS was calculated and who underwent stress MPS within 3 months. Patients with known coronary artery disease, prior coronary revascularization, and those undergoing hemodialysis were excluded.

High Wall Shear Stress Is Related to Atherosclerotic Plaque Rupture in the Aortic Arch of Patients with Cardiovascular Disease: A Study with Computational Fluid Dynamics Model and Non-Obstructive General Angioscopy.

Aims: Wall shear stress (WSS) has been considered a major determinant of aortic atherosclerosis. Recently, non-obstructive general angioscopy (NOGA) was developed to visualize various atherosclerotic pathologies, including in vivo ruptured plaque (RP) in the aorta. However, the relationship between aortic RP and WSS distribution within the aortic wall is unclear.

Hybrid Assessment of Myocardial Ischemia Using Stress-Only Nuclear Myocardial Perfusion Imaging and Rest Computed Tomography Perfusion Imaging.

Background: Sequential assessment using CT coronary angiography (coronary CT) and nuclear myocardial perfusion imaging (MPI) is considered an anatomical and functional evaluation of coronary artery disease (CAD). However, there can be unexpected radiation exposure. Hybrid MPI with stress-only nuclear MPI and rest CT-MPI using coronary CT may contribute to reducing the radiation dose in sequential assessment with nuclear MPI after coronary CT.

Prognostic Value of Left Ventricular Dyssynchrony Assessed with Nuclear Cardiology in Patients with Known or Suspected Stable Coronary Artery Disease with Preserved Left Ventricular Ejection Fraction.

Left ventricular (LV) mechanical dyssynchrony assessed with phase analysis of electrocardiogram (ECG) -gated single photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) is useful for predicting major cardiac events (MCEs) in patients with cardiac dysfunction. However, there is no report on its usefulness in Japanese patients with known or suspected stable coronary artery disease (CAD) with preserved LV ejection fraction (LVEF).We retrospectively investigated 3,374 consecutive patients with known or suspected CAD who underwent rest Tl and stress Tc-tetrofosmin ECG-gated SPECT MPI and had preserved LVEF (≥ 45%), and followed them up to confirm their prognosis for three years.

Prognostic Significance of the Residual SYNTAX Score and Ischemic Reduction Detected with Nuclear Cardiology for Prediction of Major Cardiac Events after Revascularization.

Objective There is no report on the risk stratification of major cardiac events (MCEs) with a combination of the Synergy between Percutaneous Coronary Intervention with Taxus and Cardiac Surgery (SYNTAX) score and ischemic reduction detected with rest Tl and stress Tc-tetrofosmin myocardial perfusion single-photon-emission computed tomography (SPECT) after revascularization in Japanese patients with coronary artery disease (CAD). Methods This was a retrospective study. The patients were followed up to confirm their prognosis for at least one year.

Risk Stratification of Cardiovascular Events in Very Elderly Patients with Known or Suspected Coronary Artery Disease Who Had Normal Single-photon Emission Computed Tomographic Myocardial Perfusion Imaging Findings.

Objective We aimed to stratify the risk of major cardiovascular (MCV) events in Japanese patients with known or suspected coronary artery disease (CAD) who had normal single-photon emission computed tomographic myocardial perfusion imaging (SPECT MPI) findings and to compare the risk by generation. Methods This was a retrospective study. The composite endpoint was the occurrence of cardiovascular death, non-fatal myocardial infarction, or non-fatal stroke.

Usefulness of Dual-Phase Snapshot 320-Detector Computed Tomography for the Detection of a Left Atrial Appendage Thrombus.

The diagnostic performance of 320-detector cardiac computed tomography (CCT) for the detection of thrombi in the left atrial appendage (LAA), relative to transesophageal echocardiography (TEE) as the gold standard, has not yet been evaluated. A total of 91 consecutive patients who were scheduled to undergo pulmonary vein isolation and underwent TEE and CCT were enrolled in this study. Delayed scanning on CCT was performed following early scanning, at 60 seconds after the start of the contrast injection.