Aims: To describe the mitral blood flow velocity distribution, we applied a freehand dynamic three-dimensional (3D) colour flow method using a moving sample surface that followed the mitral apparatus during diastole.
Methods: Nineteen healthy volunteers were studied. The ultrasound data were captured from 10-20 heartbeats at high frame rate (mean 46 frames/s) while freely tilting the transducer in an apical position. A magnetic position sensor system recorded the spatial position and orientation of the probe. Blood flow velocities were integrated across a spherical surface. In volumetric blood flow measurements this would yield angle independence of the Doppler beam. Raw digital data were analysed off-line with no loss of temporal resolution.
Results: The ratio of the maximum velocity time integral (VTI) to the mean VTI was mean 1.3 (range 1.1-1.6). At the time of peak flow the ratio of the maximum to the mean velocity was mean 1.5 (range 1.2-2.6).
Conclusion: The blood flow velocity profile was non-uniform. By using a single sample volume in Doppler measurements of the maximum VTI errors ranging from 10 to 60% may be introduced in calculations of stroke volumes.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1053/euje.2000.0041 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Low-exhaustion peripheral circulating γδ T cells serve as a biomarker for predicting the clinical benefit rate of non-small cell lung cancer (NSCLC) patients to chemotherapy or targeted therapy: a single-center retrospective study.
BMC Cancer
January 2025
Guangdong Provincial Key Laboratory of Tumor Interventional Diagnosis and Treatment, Zhuhai Institute of Translational Medicine, Zhuhai People's Hospital Affiliated with Jinan University, Jinan University, Zhuhai, China.
Background: Multiple studies have demonstrated that the abundance and functionality of γδ T cells are favorable prognostic indicators for prolonged survival in cancer patients. However, the association between the immunophenotype of circulating γδ T cells and the therapeutic response in NSCLC patients undergoing chemotherapy or targeted therapy remains unclear.
Methods: Patients with EGFR wild-type (EGFR-WT) or mutant (EGFR-Mut) non-small cell lung cancer (NSCLC), diagnosed between January 2020 and January 2024, were included in this study.
Ursodeoxycholic acid protects against sepsis-induced acute kidney injury by activating Nrf2/HO-1 and inhibiting NF-κB pathway.
BMC Nephrol
January 2025
Department of Intensive Care Medicine, No. 971st Hospital of the People's Liberation Army Navy, Qingdao, Shandong Province, PR China.
Background: Ursodeoxycholic acid (UDCA), traditionally recognized for its hepatoprotective effects, has also shown potential in protecting kidney injury. This study aimed to evaluate the protective effects of UDCA against sepsis-induced acute kidney injury (AKI) and to elucidate the underlying mechanisms.
Methods: Sixty male C57BL/6 N mice were utilized to establish a sepsis-induced AKI model through intravenous injection of lipopolysaccharides (LPS, 10 mg/kg).
Comparison of global and regional myocardial blood flow quantification using dynamic solid-state detector SPECT and Tc-99 m-sestamibi or Tc-99 m-tetrofosmin in a routine clinical setting.
Int J Cardiovasc Imaging
January 2025
Department of Nuclear Medicine, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany.
Solid-state detector single photon emission computed tomography (SPECT) enables the acquisition of dynamic data for calculation of myocardial blood flow (MBF) and myocardial flow reserve (MFR). Here, we report about our experiences on routine clinical use and robustness using Tc-99 m-sestamibi and Tc-99 m-tetrofosmin. 307 patients underwent dynamic list-mode myocardial perfusion imaging (MPI) and standard static MPI for clinical workup of coronary artery disease on a dedicated cardiac SPECT camera.
View Article and Find Full Text PDFTissue oxygenation in response to low-load and high-load back squats with continuous blood flow restriction in athletes.
J Sports Sci
January 2025
Department of Tourism, Sport and Society, Lincoln University, Christchurch, New Zealand.
To determine muscle oxygenation with continuous blood flow restriction (BFR) training in high load (HL), 80% one-repetition maximum (1RM) and low load (LL), 30% 1RM squat exercises. In week-2 of a 4-week resistance training programme as part of their 3-set training routine, two groups of athletes ( = 4 each), one performing HL training with low cuff pressure (20% arterial occlusion pressure (AOP)), the other LL training with high cuff pressure (60% AOP) had muscle oxygenation assessed with near-infrared spectrophotometry (NIRS), arterial oxygen saturation (SPO), heart rate (HR), barbell velocity and ratings of perceived exertion (RPE) during barbell back squats (BBS). Changes in the vastus lateralis oximetry were compared to pre- and post-training squat (1RM).
View Article and Find Full Text PDFPhysiologically based pharmacokinetic modeling of small molecules: How much progress have we made?
Drug Metab Dispos
January 2025
Department of Pharmaceutics, School of Pharmacy, University of Washington, Seattle, Washington. Electronic address:
Physiologically based pharmacokinetic (PBPK) models of small molecules have become mainstream in drug development and in academic research. The use of PBPK models is continuously expanding, with the majority of work now focusing on predictions of drug-drug interactions, drug-disease interactions, and changes in drug disposition across lifespan. Recently, publications that use PBPK modeling to predict drug disposition during pregnancy and in organ impairment have increased reflecting the advances in incorporating diverse physiologic changes into the models.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!