Effect of propranolol and isoprenaline on regional left ventricular blood flow in experimental myocardial ischaemia

1975 ◽  
Vol 9 (2) ◽  
pp. 178-186 ◽  
Author(s):  
L. C. BECKER ◽  
R. FERREIRA ◽  
M. THOMAS
2003 ◽  
Vol 13 (5) ◽  
pp. 469-471 ◽  
Author(s):  
Przemysław Palka ◽  
Aleksandra Lange ◽  
Cameron Ward

We describe the clinical features of idiopathic restrictive cardiomyopathy in a female infant. A marked elevation of left ventricular end-diastolic pressure, and profoundly abnormal myocardial relaxation, were detected with the use of Doppler blood flow echocardiography, coupled with the relatively new technique of Doppler tissue echocardiography. There was no clinical evidence of ongoing heart failure, but she had signs of myocardial ischaemia, and unfortunately died suddenly at the age of 13 months.


2001 ◽  
Vol 40 (05) ◽  
pp. 164-171 ◽  
Author(s):  
B. Nowak ◽  
H.-J. Kaiser ◽  
S. Block ◽  
K.-C. Koch ◽  
J. vom Dahl ◽  
...  

Summary Aim: In the present study a new approach has been developed for comparative quantification of absolute myocardial blood flow (MBF), myocardial perfusion, and myocardial metabolism in short-axis slices. Methods: 42 patients with severe CAD, referred for myocardial viability diagnostics, were studied consecutively with 0-15-H2O PET (H2O-PET) (twice), Tc-99m-Tetrofosmin 5PECT (TT-SPECT) and F-18-FDG PET (FDG-PET). All dato sets were reconstructed using attenuation correction and reoriented into short axis slices. Each heart was divided into three representative slices (base, rnidventricular, apex) and 18 ROIs were defined on the FDG PET images and transferred to the corresponding H2O-PET and TT-SPECT slices. TT-SPECT and FDG-PET data were normalized to the ROI showing maximum perfusion. MBF was calculated for all left-ventricular ROIs using a single-compartment-model fitting the dynamic H2O-PET studies. Microsphere equivalent MBF (MBF_micr) was calculated by multiplying MBF and tissue-fraction, a parameter which was obtained by fitting the dynamic H2O-PET studies. To reduce influence of viability only well perfused areas (>70% TT-SPECT) were used for comparative quantification. Results: First and second mean global MBF values were 0.85 ml × min-1 × g-1 and 0.84 ml × min-1 × g1, respectively, with a repeatability coefficient of 0.30 ml ÷ min-1 × gl. After sectorization mean MBF_micr was between 0.58 ml × min1 ÷ ml"1 and 0.68 ml × min-1 × ml"1 in well perfused areas. Corresponding TT-SPECT values ranged from 83 % to 91 %, and FDG-PET values from 91 % to 103%. All procedures yielded higher values for the lateral than the septal regions. Conclusion: Comparative quantification of MBF, MBF_micr, TT-SPECT perfusion and FDG-PET metabolism can be done with the introduced method in short axis slices. The obtained values agree well with experimentally validated values of MBF and MBF_micr.


2014 ◽  
Vol 17 (5) ◽  
pp. 269
Author(s):  
Shinya Takahashi ◽  
Taiichi Takasaki ◽  
Futoshi Tadehara ◽  
Takahiro Taguchi ◽  
Keijiro Katayama ◽  
...  

An 86-year-old woman presented with chest pain and discomfort. Echocardiography revealed severe aortic valve stenosis and asymmetric septal hypertrophy. Aortic valve replacement and myectomy were performed using a curved knife. The blade was U-shaped in cross-section, and was curved upward along the long axis. Hypertrophic septal myocardium was removed along the long axis of the left ventricle (LV), and a groove for blood flow was constructed. The patient was discharged uneventfully without recurrence of her chest discomfort. Our result suggested that a curved knife is a reasonable option for transaortic septal myectomy in patients with obstructive LV hypertrophy.


Circulation ◽  
1995 ◽  
Vol 92 (9) ◽  
pp. 298-303 ◽  
Author(s):  
Takuya Miura ◽  
Takeshi Hiramatsu ◽  
Joseph M. Forbess ◽  
John E. Mayer

1992 ◽  
Vol 262 (1) ◽  
pp. H68-H77
Author(s):  
F. L. Abel ◽  
R. R. Zhao ◽  
R. F. Bond

Effects of ventricular compression on maximally dilated left circumflex coronary blood flow were investigated in seven mongrel dogs under pentobarbital anesthesia. The left circumflex artery was perfused with the animals' own blood at a constant pressure (63 mmHg) while left ventricular pressure was experimentally altered. Adenosine was infused to produce maximal vasodilation, verified by the hyperemic response to coronary occlusion. Alterations of peak left ventricular pressure from 50 to 250 mmHg resulted in a linear decrease in total circumflex flow of 1.10 ml.min-1 x 100 g heart wt-1 for each 10 mmHg of peak ventricular to coronary perfusion pressure gradient; a 2.6% decrease from control levels. Similar slopes were obtained for systolic and diastolic flows as for total mean flow, implying equal compressive forces in systole as in diastole. Increases in left ventricular end-diastolic pressure accounted for 29% of the flow changes associated with an increase in peak ventricular pressure. Doubling circumferential wall tension had a minimal effect on total circumflex flow. When the slopes were extrapolated to zero, assuming linearity, a peak left ventricular pressure of 385 mmHg greater than coronary perfusion pressure would be required to reduce coronary flow to zero. The experiments were repeated in five additional animals but at different perfusion pressures from 40 to 160 mmHg. Higher perfusion pressures gave similar results but with even less effect of ventricular pressure on coronary flow or coronary conductance. These results argue for an active storage site for systolic arterial flow in the dilated coronary system.


1981 ◽  
Vol 240 (5) ◽  
pp. H804-H810 ◽  
Author(s):  
H. D. Kleinert ◽  
H. R. Weiss

Blood flow and high-energy phosphate (HEP) content were determined simultaneously in multiple microregions of left ventricular subendocardium in 29 normal anesthetized open-chest rabbits by use of a new micromethod to determine whether a direct linear relationship existed between these parameters. Tissue samples weighed 1-2 mg. ATP and creatine phosphate (CP) content were quantitated in quick-frozen hearts by fluorometry at sites where tissue perfusion was measured by H2 clearance by use of bare-tipped platinum electrodes. A series of validation studies were conducted to ensure that 1) no significant damage to the tissue surrounding the electrode occurred during the period of experimentation and 2) no significant loss of biochemical constituents had occurred due to labile processes during freezing or storage of the tissue. Blood flow, ATP, and CP values averaged 79.1 +/- 24.1 (SD) ml.min-1.100 g-1, 4.9 +/- 1.3 mumol/g tissue, and 8.0 +/- 3.0 mumol/g tissue, respectively, and are similar to those reported in studies using larger tissue samples. Correlation between the heterogeneous distribution of tissue perfusion and HEP revealed no direct linear relationship between these parameters in the normal unstressed rabbit subendocardium.


2013 ◽  
Vol 118 (4) ◽  
pp. 796-808 ◽  
Author(s):  
Pornswan Ngamprasertwong ◽  
Erik C. Michelfelder ◽  
Shahriar Arbabi ◽  
Yun Suk Choi ◽  
Christopher Statile ◽  
...  

Abstract Background: Use of high-dose inhalational anesthesia during open fetal surgery may induce maternal–fetal hemodynamic instability and fetal myocardial depression. The authors’ preliminary human retrospective study demonstrated less fetal bradycardia and left ventricular systolic dysfunction with lower dose desflurane supplemented with propofol and remifentanil IV anesthesia (SIVA). In this animal study, the authors compare maternal–fetal effects of high-dose desflurane anesthesia (HD-DES) and SIVA. Methods: Of 26 instrumented midgestational ewes, data from 11 animals exposed to both SIVA and HD-DES in random sequences and six animals exposed to HD-DES while maternal normotension was maintained were analyzed. Maternal electroencephalography was used to guide comparable depths of anesthesia in both techniques. Hemodynamic parameters, blood gas, and fetal cardiac function from echocardiography were recorded. Results: Compared with SIVA, HD-DES resulted in significant maternal hypotension (mean arterial pressure difference, 19.53 mmHg; 95% CI, 17.6–21.4; P < 0.0001), fetal acidosis (pH 7.11 vs. 7.24 at 150 min, P < 0.001), and decreased uterine blood flow. In the HD-DES group with maternal normotension, uterine blood flow still declined and fetal acidosis persisted, with no statistically significant difference from the group exposed to HD-DES that had maternal hypotension. There was no statistically significant difference in fetal cardiac function. Conclusion: In sheep, SIVA affects maternal hemodynamics less and provides better fetal acid/base status than high-dose desflurane. Fetal echocardiography did not reflect myocardial dysfunction in this model.


1962 ◽  
Vol 203 (1) ◽  
pp. 122-124 ◽  
Author(s):  
J. A. Herd ◽  
M. Hollenberg ◽  
G. D. Thorburn ◽  
H. H. Kopald ◽  
A. C. Barger

Serial, rapid measurements of left ventricular myocardial blood flow in trained, unanesthetized dogs have been made by injecting krypton 85 through chronically implanted coronary artery catheters and counting with an external scintillation detector. Precordial radioactivity declined as a single exponential function during the first 2 min after injection, suggesting a single rate of myocardial blood flow. Simultaneous estimations with Kr85 and blood flowmeters in acute experiments established the accuracy and reproducibility of the technique. Myocardial blood flows between 40 and 55 ml/100 g/min were observed repeatedly in three well-trained, unanesthetized dogs in the basal state.


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