Objectives: The purpose of this study is to validate the accuracy of multidetector computed tomography (MDCT) to measure differences in regional myocardial perfusion during adenosine stress in a canine model of left anterior descending (LAD) artery stenosis, during first-pass, contrast-enhanced helical MDCT.
Background: Myocardial perfusion imaging by MDCT may have significant implications in the diagnosis and treatment of coronary artery disease.
Methods: Eight dogs were prepared with a LAD stenosis, and contrast-enhanced MDCT imaging was performed 5 min into adenosine infusion (0.14 to 0.21 mg/kg/min). Images were analyzed using a semiautomated approach to define the regional signal density (SD) ratio (myocardial SD/left ventricular blood pool SD) in stenosed and remote territories, and then compared with microsphere myocardial blood flow (MBF) measurements.
Results: Mean MBF in stenosed versus remote territories was 1.37 +/- 0.46 ml/g/min and 1.29 +/- 0.48 ml/g/min at baseline (p = NS) and 2.54 +/- 0.93 ml/g/min and 8.94 +/- 5.74 ml/g/min during adenosine infusion, respectively (p < 0.05). Myocardial SD was 92.3 +/- 39.5 HU in stenosed versus 180.4 +/- 41.9 HU in remote territories (p < 0.001). There was a significant linear association of the SD ratio with MBF in the stenosed territory (R = 0.98, p = 0.001) and between regional myocardial SD ratio and MBF <8 ml/g/min, slope = 0.035, SE = 0.007, p < 0.0001. Overall, there was a significant non-linear relationship over the range of flows studied (LR chi-square [2 degrees of freedom] = 31.8, p < 0.0001).
Conclusions: Adenosine-augmented MDCT myocardial perfusion imaging provides semiquantitative measurements of myocardial perfusion during first-pass MDCT imaging in a canine model of LAD stenosis.
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http://dx.doi.org/10.1016/j.jacc.2006.04.014 | DOI Listing |
PLoS One
January 2025
Electrical, Mechanical & Computer Engineering School, Federal University of Goias, Goiania, Brazil.
This paper proposes the use of artificial intelligence techniques, specifically the nnU-Net convolutional neural network, to improve the identification of left ventricular walls in images of myocardial perfusion scintigraphy, with the objective of improving the diagnosis and treatment of coronary artery disease. The methodology included data collection in a clinical environment, followed by data preparation and analysis using the 3D Slicer Platform for manual segmentation, and subsequently, the application of artificial intelligence models for automated segmentation, focusing on the efficiency of identifying the walls of the left ventricular. A total of 83 clinical routine exams were collected, each exam containing 50 slices, which is 4,150 images.
View Article and Find Full Text PDFCurr Cardiol Rep
January 2025
Department of Cardiovascular Disease, Mayo Clinic, Rochester, MN, USA.
Purpose Of Review: Critical Care Echocardiography (CCE) is now established as an important tool in the intensive care unit (ICU). This paper aims to examine the expanding role of cardiovascular ultrasound in the ICU, focusing on its applications, benefits, and challenges, while highlighting recent advancements shaping the future of critical care echocardiography.
Recent Findings: Non-invasive echocardiographic measurement of hemodynamic parameters including stroke volume, cardiac output, left ventricular filling pressures, and pulmonary pressures have been well-validated against invasive measurements.
J Nucl Med
January 2025
Milstein Division of Cardiology, Department of Medicine, Columbia University Irving Medical Center, NewYork-Presbyterian Hospital, New York, New York;
Cardiac allograft vasculopathy (CAV) causes impaired blood flow in both epicardial vessels and microvasculature and remains a leading cause of posttransplant morbidity and mortality. This study examined the prognostic value and outcomes of CAV, assessed by N-ammonia PET/CT myocardial perfusion imaging in heart transplant recipients. PET/CT and invasive coronary angiography (ICA) were graded using validated scales.
View Article and Find Full Text PDFHeart
January 2025
Cardiology, University Hospital of Copenhagen, Copenhagen, Denmark.
Acute myocardial infarction-related cardiogenic shock (AMI-CS) is a severe, life-threatening condition characterised by inadequate tissue perfusion due to the heart's inability to pump blood effectively. The pathophysiology of AMI-CS usually arises from the sudden loss of myocardial contractility, leading to a decrease in cardiac output and systemic hypoperfusion. In approximately 90% of AMI-CS cases, the left ventricle is the primary site of dysfunction.
View Article and Find Full Text PDFCurr Pediatr Rep
May 2024
Coronary Artery Anomalies Program, Division of Cardiology, Texas Children's Hospital, 6651 Main Street MC-E1920, Houston, TX 77030 USA.
Purpose Of Review: We present a contemporary approach to risk assessment and management of patients with anomalous aortic origin of a coronary artery (AAOCA).
Recent Findings: Anomalous left coronary artery from the right aortic sinus (L-AAOCA) with interarterial course carries a high risk of sudden cardiac death (SCD); therefore, current guidelines recommend exercise restriction and surgical intervention. Recent data in intraseptal and juxtacommissural L-AAOCA showed inducible perfusion abnormalities, leading to consideration of surgical intervention.
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