Background: Cardiac memory (CM) refers to persistent T-wave changes that appear after cessation of a period of abnormal ventricular activation, such as ventricular pacing. Prior animal studies using tagged magnetic resonance imaging have suggested that CM is associated with prolonged action potential duration and increased strain of late-activated myocardial segments.
Objective: The aim of the present study is to determine whether CM induced by ventricular pacing in human subjects is accompanied by regional mechanical changes in late-activated myocardial segments, assessed by left ventricular (LV) longitudinal strain (peak LS) and time-to-peak longitudinal strain (TTP-LS), using 2D-speckle tracking echocardiography (2DSE).
Material And Methods: We included 20 patients (16 women, age 71±11 years), with DDD pacemakers and with normal AV conduction and QRS/T morphology at baseline. CM was induced by DDD pacing with a short AV delay. ECGs and 2DSE were performed before pacing (baseline), at peak CM (immediately after two weeks of pacing), and at CM washout (4 weeks after cessation of pacing). We measured by echocardiography: left ventricular (LV) ejection fraction, LV diastolic function (E, A, E/E'), peak LS and TTP-LS for the earliest (i.e. adjacent to the pacing site) and latest (i.e. latest-activated during ventricular pacing) segments, using an 18-segment LV model.
Results: All patients had electrical (ECG) CM changes, which disappeared by CM washout. LV global systolic and diastolic functions, as well as regional LS (peak LS for both the latest and earliest activated segments) were similar between evaluations. TTP for the latest and earliest activated segments, as well as mean TTP-LS, increased from baseline to peak CM, but did not decrease at CM washout. The dispersion of TTP-LS was not changed.
Conclusion: These results suggest that regional mechanical changes, as can be assessed by 2DSE longitudinal strain, do not overlap electrical CM.
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http://dx.doi.org/10.26574/maedica.2018.13.3.189 | DOI Listing |
Echocardiography
March 2025
Department of Physical Therapy, Faculty of Health Science, Kyorin University, Mitaka City, Tokyo, Japan.
Purpose: Central hypovolemia is considered to lead to a compensatory increase in cardiac contractility. From a physiological perspective, left ventricular (LV) twisting motion, which plays an important role in maintaining cardiac output, should be enhanced during central hypovolemia, but previous studies have shown inconsistent findings. Using 3D echocardiography, we tested the hypothesis that the LV twisting and untwisting motion would be enhanced during severe central hypovolemia.
View Article and Find Full Text PDFJpn J Radiol
March 2025
Department of Mechanical Engineering, Koc University, Istanbul, Turkey.
Purpose: In patients with repaired tetralogy of Fallot, transcatheter or surgical pulmonary valve replacement is recommended. However, it is not clear whether pulmonary valve replacement preserves systolic and diastolic functions of both ventricles. The aim of the study is to investigate the impact of transcatheter pulmonary valve replacement on atrial and ventricular myocardial strain changes by feature-tracking cardiac magnetic resonance imaging.
View Article and Find Full Text PDFSci Rep
March 2025
Department of Cardiovascular Ultrasound, The First Affiliated Hospital of China Medical University, 155 North Nanjing Street, Heping District, Shenyang, 110001, China.
Contemporary classification of hypertrophic cardiomyopathy (HCM) was mainly based on the site of myocardial hypertrophy and left ventricular outflow tract obstruction. A complementary classification based on left ventricular function could provide a powerful tool to identify individuals with high risk of adverse cardiovascular outcomes and guide individualized managements. Multi-dimensional echocardiographic parameters of left ventricular function derived from conventional echocardiography, tissue Doppler imaging, and speckle tracking echocardiography were obtained in 266 HCM patients and 169 healthy controls (HCs).
View Article and Find Full Text PDFSci Rep
March 2025
Department of Diagnostic and Interventional Radiology, Faculty of Medicine, Mansoura University, 12 El-Gomhoreya street, 35112, Mansoura, Egypt.
Girls and women with Turner syndrome (TS) suffer from increased risk of cardiovascular diseases. We hypothesized that left ventricular (LV) myocardial strain and aortic elasticity will be impaired in girls with TS. Cardiac MRI of 45 girls with TS and 14 healthy control girls was performed.
View Article and Find Full Text PDFArch Cardiovasc Dis
February 2025
Bordeaux University Hospital, 33000 Bordeaux, France; University of Bordeaux, 33000 Bordeaux, France; CIC-P 1401, 33600 Bordeaux-Pessac, France; Inserm 1045, 33600 Pessac, France.
Background: Patients with left ventricular hypertrophy (LVH) often maintain preserved left ventricular ejection fraction in the early stages of the disease. There is a need to identify simple and reliable variables beyond left ventricular ejection fraction to recognize those at risk of developing adverse clinical outcomes.
Aims: To examine left atrial (LA) strain in patients with hypertrophic cardiomyopathy (HCM), cardiac amyloidosis (CA) and Fabry disease (FD), pathologies known to cause LVH, and the relationship between LA strain and adverse clinical outcomes.
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