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Eric A. Rose - One of the best experts on this subject based on the ideXlab platform.
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Discriminating between preservation and reperfusion injury in human cardiac allografts using Heart Weight and left ventricular mass.
Circulation, 1995Co-Authors: James P. Slater, Mehrdad M.r. Amirhamzeh, Osvaldo J. Yano, Joanne P. Starr, Richard J. Kaplon, William Burfeind, Robert E. Michler, A S Shah, P Pepino, Eric A. RoseAbstract:Myocardial edema caused by injury during preservation or reperfusion can affect cardiac function after Heart transplantation. This study was designed to distinguish these forms of injury in human allografts. In 15 donor Hearts preserved in University of Wisconsin solution, Heart Weight (HW) was obtained immediately after explantation and after transport before implantation. Left ventricular mass (LVM) was calculated separately in 18 patients with the use of epicardial two-dimensional echocardiograms obtained both before explantation from the donor and after transplantation and weaning from cardiopulmonary bypass. While changes in LVM could be due to preservation or reperfusion injury, changes in HW can only be due to edema occurring during transport. HW averaged 339 +/- 24 g (mean +/- SE) before and 340 +/- 24 g after transport (P = NS); however, LVM increased 14 g, from 164 +/- 8 to 178 +/- 11 g (P < .05, paired t test). LVM increased in 10 of 18 patients (56%). No correlation was demonstrated between duration of ischemia (mean, 172 +/- 13 minutes) and changes in HW or LVM. Two patients died as a result of primary graft failure. In the first, HW increased 54 g, 2 SD above the mean. In the second, LVM increased 66 g, 2 SD above the mean, but HW changed minimally. While current preservation methods result in minimal change in HW during transport, reperfusion injury frequently increases LVM. LVM determination by two-dimensional echocardiography may prove valuable in detecting allograft injury.
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Discriminating Between Preservation and Reperfusion Injury in Human Cardiac Allografts Using Heart Weight and Left Ventricular Mass
Circulation, 1995Co-Authors: James P. Slater, Mehrdad M.r. Amirhamzeh, Osvaldo J. Yano, Aamir Shah, Joanne P. Starr, Richard J. Kaplon, William Burfeind, Pepino P, Robert E. Michler, Eric A. RoseAbstract:Background Myocardial edema caused by injury during preservation or reperfusion can affect cardiac function after Heart transplantation. This study was designed to distinguish these forms of injury in human allografts. Methods and Results In 15 donor Hearts preserved in University of Wisconsin solution, Heart Weight (HW) was obtained immediately after explantation and after transport before implantation. Left ventricular mass (LVM) was calculated separately in 18 patients with the use of epicardial two-dimensional echocardiograms obtained both before explantation from the donor and after transplantation and weaning from cardiopulmonary bypass. While changes in LVM could be due to preservation or reperfusion injury, changes in HW can only be due to edema occurring during transport. HW averaged 339±24 g (mean±SE) before and 340±24 g after transport ( P =NS); however, LVM increased 14 g, from 164±8 to 178±11 g ( P
James P. Slater - One of the best experts on this subject based on the ideXlab platform.
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Discriminating between preservation and reperfusion injury in human cardiac allografts using Heart Weight and left ventricular mass.
Circulation, 1995Co-Authors: James P. Slater, Mehrdad M.r. Amirhamzeh, Osvaldo J. Yano, Joanne P. Starr, Richard J. Kaplon, William Burfeind, Robert E. Michler, A S Shah, P Pepino, Eric A. RoseAbstract:Myocardial edema caused by injury during preservation or reperfusion can affect cardiac function after Heart transplantation. This study was designed to distinguish these forms of injury in human allografts. In 15 donor Hearts preserved in University of Wisconsin solution, Heart Weight (HW) was obtained immediately after explantation and after transport before implantation. Left ventricular mass (LVM) was calculated separately in 18 patients with the use of epicardial two-dimensional echocardiograms obtained both before explantation from the donor and after transplantation and weaning from cardiopulmonary bypass. While changes in LVM could be due to preservation or reperfusion injury, changes in HW can only be due to edema occurring during transport. HW averaged 339 +/- 24 g (mean +/- SE) before and 340 +/- 24 g after transport (P = NS); however, LVM increased 14 g, from 164 +/- 8 to 178 +/- 11 g (P < .05, paired t test). LVM increased in 10 of 18 patients (56%). No correlation was demonstrated between duration of ischemia (mean, 172 +/- 13 minutes) and changes in HW or LVM. Two patients died as a result of primary graft failure. In the first, HW increased 54 g, 2 SD above the mean. In the second, LVM increased 66 g, 2 SD above the mean, but HW changed minimally. While current preservation methods result in minimal change in HW during transport, reperfusion injury frequently increases LVM. LVM determination by two-dimensional echocardiography may prove valuable in detecting allograft injury.
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Discriminating Between Preservation and Reperfusion Injury in Human Cardiac Allografts Using Heart Weight and Left Ventricular Mass
Circulation, 1995Co-Authors: James P. Slater, Mehrdad M.r. Amirhamzeh, Osvaldo J. Yano, Aamir Shah, Joanne P. Starr, Richard J. Kaplon, William Burfeind, Pepino P, Robert E. Michler, Eric A. RoseAbstract:Background Myocardial edema caused by injury during preservation or reperfusion can affect cardiac function after Heart transplantation. This study was designed to distinguish these forms of injury in human allografts. Methods and Results In 15 donor Hearts preserved in University of Wisconsin solution, Heart Weight (HW) was obtained immediately after explantation and after transport before implantation. Left ventricular mass (LVM) was calculated separately in 18 patients with the use of epicardial two-dimensional echocardiograms obtained both before explantation from the donor and after transplantation and weaning from cardiopulmonary bypass. While changes in LVM could be due to preservation or reperfusion injury, changes in HW can only be due to edema occurring during transport. HW averaged 339±24 g (mean±SE) before and 340±24 g after transport ( P =NS); however, LVM increased 14 g, from 164±8 to 178±11 g ( P
Max E. Valentinuzzi - One of the best experts on this subject based on the ideXlab platform.
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Heart Weight affects spontaneous defibrillation but not ventricular fibrillation threshold.
Pacing and clinical electrophysiology : PACE, 1994Co-Authors: Estela Ruiz, Max E. ValentinuzziAbstract:Among the factors involved in the induction, generalization, and reversion of cardiac fibrillation, the amount of tissue is a determinant factor. One question is whether an increase in myocardial mass would or would not require the same electrical threshold. Accordingly, one objective was to determine if ventricular Weight (VW) has any effect on the fibrillation thresholds (FTs). A second objective was to find a possible relationship between spontaneous defibrillation (SPDE) and Heart Weight. Fifty mongrel dogs of both sexes were used, of which 26 were 2- to 10-week-old puppies. The rest were adult animals of undetermined age. Fibrillation was induced with two types of stimuli directly applied to the Heart. The stimuli were a train of rectangular pulses (TP) not synchronized with the ECG, and single pulses (SP) synchronized with and delayed from the R wave. TP type was used in one group with paddle electrodes; and the TP and SP types were used in a second group with hook electrodes. For both types, stimulation started at a low current and was increased until fibrillation was triggered. Once defibrillated, either spontaneously or by electrical shock, the procedure was repeated. Correlation coefficients between FT and VW were low (< 0.4), and scaling of the thresholds to VW resulted in hyperbolic relationship, for all cases, thus suggesting independence of the two parameters. SPDE fell sharply with Weight. For values higher than 12 grams it was essentially nonexistent. VW does not have any effect on the FT but it dramatically influences the capacity of the myocardium to revert the arrhythmia by itself.
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Cardiac fibrillation and Heart Weight
Proceedings of the Annual International Conference of the IEEE Engineering in Medicine and Biology Society, 1992Co-Authors: Estela Ruiz, Max E. ValentinuzziAbstract:The existence of a minimal mass of tissue is an essential condition to trigger fibrillation. We asked whether the current required to induce fibrillation of this Mass is the saae as that required for larger masses. Fibrillation thresholds were determined in canine and feline ventricles of a wide range of sizes (1.7–102g) by using combinations of electrode leads and stimili directly applied to the myocardium. No significant differences were found among values nor definite trends could be observed when plotting stimulus amplitude as a function of ventricular Weight. It was concluded that Heart Weight did not affect the fibrillation threshold.
Jeremy N Skepper - One of the best experts on this subject based on the ideXlab platform.
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capillary surface area is reduced and tissue thickness from capillaries to myocytes is increased in the left ventricle of streptozotocin diabetic rats
Diabetologia, 1995Co-Authors: Alice Warley, J M Powell, Jeremy N SkepperAbstract:The left ventricles of normal and diabetic rats, fixed by vascular perfusion were examined using modern stereological techniques to quantify changes in the morphology accompanying streptozotocin-induced diabetes. The Heart Weight to body Weight ratio increased in diabetic rats whilst left ventricular volume remained unchanged. Papillary muscles from the diabetic animals showed prolonged time to peak tension and relaxation, and altered sensitivity to adrenalin and calcium. The apparent cardiomyopathy observed when body Weight loss exceeds Heart Weight loss in experimental diabetes was accompanied by specific pathological changes in the composition of the left ventricle. In the diabetic animals the volume of extracellular components increased threefold and the volume of capillaries fell. The surface density and total surface area of capillaries was reduced, and oxygen diffusion distance to myocyte mitochondria increased. The volume fraction of myocyte mitochondria was reduced during streptozotocin-induced diabetes.
Richard J. Kaplon - One of the best experts on this subject based on the ideXlab platform.
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Discriminating between preservation and reperfusion injury in human cardiac allografts using Heart Weight and left ventricular mass.
Circulation, 1995Co-Authors: James P. Slater, Mehrdad M.r. Amirhamzeh, Osvaldo J. Yano, Joanne P. Starr, Richard J. Kaplon, William Burfeind, Robert E. Michler, A S Shah, P Pepino, Eric A. RoseAbstract:Myocardial edema caused by injury during preservation or reperfusion can affect cardiac function after Heart transplantation. This study was designed to distinguish these forms of injury in human allografts. In 15 donor Hearts preserved in University of Wisconsin solution, Heart Weight (HW) was obtained immediately after explantation and after transport before implantation. Left ventricular mass (LVM) was calculated separately in 18 patients with the use of epicardial two-dimensional echocardiograms obtained both before explantation from the donor and after transplantation and weaning from cardiopulmonary bypass. While changes in LVM could be due to preservation or reperfusion injury, changes in HW can only be due to edema occurring during transport. HW averaged 339 +/- 24 g (mean +/- SE) before and 340 +/- 24 g after transport (P = NS); however, LVM increased 14 g, from 164 +/- 8 to 178 +/- 11 g (P < .05, paired t test). LVM increased in 10 of 18 patients (56%). No correlation was demonstrated between duration of ischemia (mean, 172 +/- 13 minutes) and changes in HW or LVM. Two patients died as a result of primary graft failure. In the first, HW increased 54 g, 2 SD above the mean. In the second, LVM increased 66 g, 2 SD above the mean, but HW changed minimally. While current preservation methods result in minimal change in HW during transport, reperfusion injury frequently increases LVM. LVM determination by two-dimensional echocardiography may prove valuable in detecting allograft injury.
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Discriminating Between Preservation and Reperfusion Injury in Human Cardiac Allografts Using Heart Weight and Left Ventricular Mass
Circulation, 1995Co-Authors: James P. Slater, Mehrdad M.r. Amirhamzeh, Osvaldo J. Yano, Aamir Shah, Joanne P. Starr, Richard J. Kaplon, William Burfeind, Pepino P, Robert E. Michler, Eric A. RoseAbstract:Background Myocardial edema caused by injury during preservation or reperfusion can affect cardiac function after Heart transplantation. This study was designed to distinguish these forms of injury in human allografts. Methods and Results In 15 donor Hearts preserved in University of Wisconsin solution, Heart Weight (HW) was obtained immediately after explantation and after transport before implantation. Left ventricular mass (LVM) was calculated separately in 18 patients with the use of epicardial two-dimensional echocardiograms obtained both before explantation from the donor and after transplantation and weaning from cardiopulmonary bypass. While changes in LVM could be due to preservation or reperfusion injury, changes in HW can only be due to edema occurring during transport. HW averaged 339±24 g (mean±SE) before and 340±24 g after transport ( P =NS); however, LVM increased 14 g, from 164±8 to 178±11 g ( P
