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Diastolic Flow (diastolic + flow)

Distribution by Scientific Domains
Medical Sciences100%

Terms modified by Diastolic Flow

  • diastolic flow velocity
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    Selected Abstracts

    Transesophageal and Transpharyngeal Ultrasound Demonstration of Reversed Diastolic Flow in Aortic Arch Branches and Neck Vessels in Severe Aortic Regurgitation

    ECHOCARDIOGRAPHY, Issue 4 2004
    Deepak Khanna M.D.
    In the current study, we describe an adult patient with torrential aortic regurgitation due to an aortic dissection flap interfering with aortic cusp motion, in whom a transesophageal echocardiogram with the probe positioned in the upper esophagus and transpharyngeal ultrasound examination demonstrated prominent reversed flow throughout diastole in the left subclavian, left vertebral, left common carotid, and left internal carotid arteries. Another unique finding was the demonstration of aortic valve leaflets held in the fully opened position in diastole by the dissection flap as it prolapsed into the left ventricular outflow tract, dramatically documenting the mechanism of torrential aortic regurgitation in this patient. (ECHOCARDIOGRAPHY, Volume 21, May 2004) [source]

    Abnormal Diastolic Flow Demonstrated by Color M Mode Echocardiography in Hypertrophic Cardiomyopathy with Mid-Ventricular Cavity Obliteration

    ECHOCARDIOGRAPHY, Issue 1 2004
    Timothy A. Mixon M.D.
    We report a case of a 55-year-old woman who presented with ventricular tachycardia and myocardial infarction. Investigations revealed no disease of the epicardial coronary arteries, but a diagnosis of hypertrophic cardiomyopathy with mid-cavitary dynamic obstruction was made. Detailed echocardiographic examination, including pulse-wave Doppler and Color M Mode recordings revealed unusual components of diastolic dysfunction. (ECHOCARDIOGRAPHY, Volume 21, January 2004) [source]

    Patent ductus arteriosus and cystic periventricular leucomalacia in preterm infants

    ACTA PAEDIATRICA, Issue 3 2001
    P Pladys
    Aim: To test the association between early disturbances in hemodynamics induced by left-to-right shunting through the duct and cystic periventricular leucomalacia. Patients: Forty-six preterm infants (27,32 wk) admitted to the neonatal intensive care unit with risk criteria. Methods: Patent ductus arteriosus was evaluated on days 1 and 4, and was significant (sPDA) in cases of absent or reversed end diastolic flow in the subductal aorta. Resistance index was measured in the anterior cerebral artery and in the subductal aorta. Main outcome: Diagnosis of cystic periventricular leucomalacia between day 10 and day 50. Results: The 12 infants who developed cystic periventricular leucomalacia were compared with those who did not. On day 1, sPDA was more frequent (64% vs 26%; p= 0.03) in the cystic periventricular leucomalacia group, left ventricular output was higher (median = 341 vs 279mlkg -1.min -1; p= 0.005), and rescue surfactant was more frequently used (83% vs 47%; p= 0.03). This latter association was confirmed by multivariate analysis. Resistance index in the anterior cerebral artery was increased in cases of significant patent ductus arteriosus (p < 0.01) and was correlated with resistance index in the subductal aorta. Conclusion: On day 1 in this selected population, sPDA has an effect on blood flow velocity waveform in cerebral arteries and is associated with an increase in the emergence of cystic periventricular leucomalacia. This association could be casual rather than causal. [source]

    Prosthetic Valve Dysfunction Presenting as Intermittent Acute Aortic Regurgitation

    ECHOCARDIOGRAPHY, Issue 8 2008
    Dali Fan M.D., Ph.D.
    We describe the case of a 43 year old man with a history of aortic stenosis, for which he had undergone aortic valve replacement in 1991 with a 25-mm Medtronic Hall prosthesis. He presented with several acute episodes of dyspnea and flash pulmonary edema. Transthoracic and transesophageal echocardiography performed to evaluate prosthetic valve function revealed evidence of "intermittent" episodes of AI, documented on color M-mode flow mapping to have a variable duration of diastolic flow (early vs. pandiastolic) across the left ventricular outflow tract and the pulse wave Doppler in the descending thoracic aorta showed similar variability in the duration of diastolic flow reversal. [source]

    Predictors for Maintenance of Sinus Rhythm after Cardioversion in Patients with Nonvalvular Atrial Fibrillation

    ECHOCARDIOGRAPHY, Issue 5 2002
    Ökçün M.D.
    Recurrence of atrial fibrillation (AF) after cardioversion (CV) to sinus rhythm (SR) is determined by various clinical and echocardiographic parameters. Transesophageal echocardiographic (TEE) parameters have been the focus of clinicians' interests for restoring and maintaining SR. This study determined the clinical, transthoracic, and TEE parameters that predict maintenance of SR in patients with nonvalvular AF after CV. We enrolled 173 patients with nonvalvular AF in the study. TEE could not be performed in 26 patients prior to CV. Twenty-five patients had spontaneously CV prior to TEE. Six patients were excluded because of left atrial (LA) thrombus assessed by TEE. CV was unsuccessful in 6 patients. The remaining 110 consecutive patients (56 men, 54 women, mean age 69 ± 9 years), who had been successfully cardioverted to SR, were prospectively included in the study. Fifty-seven (52%) patients were still in SR 6 months after CV. Age, gender, the configuration of the fibrillation wave on the electrocardiogram, pulmonary venous diastolic flow, and the presence of diabetes, hypertension, coronary artery disease, mitral annulus calcification, and mitral valve prolapse (MVP) did not predict recurrence. Duration of AF, presence of chronic obstructive pulmonary disease (COPD), LA diameter, left ventricular ejection fraction (EF), left atrial appendage peak flow (LAAPF), LAA ejection fraction (LAAEF), pulmonary venous systolic flow (PVSF), and the presence of LA spontaneous echo contrast (LASEC) predicted recurrence of AF 6 months after CV. In multivariate analysis, LAAEF < 30% was found to be the only independent variable (P < 0.0012) predicting recurrence at 6 months after CV in patients with nonvalvular AF. LAAEF more than 30% had a sensitivity of 75% and a specificity of 88% in predicting maintenance of SR 6 months after CV in patients with nonvalvular AF. In conclusion, TEE variables often used to determine thromboembolic risk also might be used to predict the outcome of CV. [source]

    Color Doppler sonography of hepatic artery reconstruction in liver transplantation

    JOURNAL OF CLINICAL ULTRASOUND, Issue 1 2002
    Alessandro De Candia MD
    Abstract Purpose The purpose of this study was to evaluate the Doppler spectral waveforms in the hepatic artery after liver transplantation and hepatic artery reconstruction by end-to-end anastomosis or aortohepatic bypass. The peak systolic velocities (PSVs), end-diastolic velocities (EDVs), and resistance indices (RIs) between the 2 reconstruction groups were compared to establish normal post-transplantation values. Methods We retrospectively reviewed the Doppler sonograms and the sonographic reports from 48 patients who had undergone liver transplantation, 30 with end-to-end arterial anastomoses and 18 with aortohepatic bypasses. All aortohepatic bypasses had been performed using the infrarenal technique. All sonographic examinations had been performed 3,6 months after transplantation in patients with no clinical sign of transplant failure and whose liver function test results more normal. We compared the mean hepatic artery PSVs, EDVs, and RIs of the 2 groups. Results Doppler spectral analysis allowed the detection of 2 types of arterial flow, a low-resistance pattern in the end-to-end anastomosis group and a high-resistance pattern with low diastolic flow in the infrarenal bypass group. The mean PSV ± standard deviation (SD) was 57 ± 16 seconds in the end-to-end anastomosis group and 62 ± 16 cm/second in the infrarenal bypass group. The mean EDV ± SD was 25 ± 14 cm/second in the end-to-end anastomosis group and 12 ± 4 cm/second in the infrarenal bypass group. The RIs ranged from 0.33 to 0.71 (mean ± SD, 0.58 ± 0.13) in the patients with end-to-end anastomoses and from 0.70 to 0.87 (mean ± SD, 0.77 ± 0.06) in those with infrarenal bypasses. The difference in the mean RIs between the 2 groups was statistically significant (p < 0.05). Conclusions Spectral waveform and RI are associated with the length and caliber of the type of hepatic artery anastomosis used. End-to-end anastomoses are short and have a uniform small caliber; aortohepatic bypasses are longer and have a progressively by smaller caliber. We must be cognizant of the method of anastomosis used when examining patients for complications after liver transplantation because the method used affects the resulting spectral waveform and RI. © 2002 John Wiley & Sons, Inc. J Clin Ultrasound 30:12,17, 2002. [source]

    The Role of Diastolic Pump Flow in Centrifugal Blood Pump Hemodynamics

    ARTIFICIAL ORGANS, Issue 9 2001
    Takehide Akimoto
    Abstract: We tried to verify the hypothesis that increases in pump flow during diastole are matched by decreases in left ventricular (LV) output during systole. A calf (80 kg) was implanted with an implantable centrifugal blood pump (EVAHEART, SunMedical Technology Research Corp., Nagano, Japan) with left ventricle to aorta (LV-Ao) bypass, and parameters were recorded at different pump speeds under general anesthesia. Pump inflow and outflow pressure, arterial pressure, systemic and pulmonary blood flow, and electrocardiogram (ECG) were recorded on the computer every 5 ms. All parameters were separated into systolic and diastolic components and analyzed. The pulmonary flow was the same as the systemic flow during the study (p > 0.1). Systemic flow consisted of pump flow and LV output through the aortic valve. The ratio of systolic pump flow to pulmonary flow (51.3%) did not change significantly at variable pump speeds (p > 0.1). The other portions of the systemic flow were shared by the left ventricular output and the pump flow during diastole. When pump flow increased during diastole, there was a corresponding decrease in the LV output (Y = ,1.068X+ 51.462; R,2 = 0.9501). These show that pump diastolic flow may regulate expansion of the left ventricle in diastole. [source]