ON THE RELATIONSHIP OF CATECHOLAMINES AND THYROID ACTIVITY TO VENTRICULAR FIBRILLATION DURING HYPOTHERMIA IN DOGS

1963 ◽  
Vol 41 (2) ◽  
pp. 361-367 ◽  
Author(s):  
D. R. Varma ◽  
R. A. Gillis ◽  
K. I. Melville
Keyword(s):  
Ventricular Fibrillation ◽  
Coronary Occlusion ◽  
Protective Action ◽  
Protective Effects ◽  
Thyroid Activity ◽  
Endogenous Catecholamines ◽  
Combined Pretreatment ◽  
Antithyroid Treatment ◽  
Relationship Of ◽  
The Relationship

The possible significance of endogenous catecholamines in the production of hypothermic ventricular fibrillation has been investigated.It is shown that in dogs under pentobarbitone anesthesia, neither iproniazid nor phenoxybenzamine pretreatment reduces the incidence of ventricular fibrillation following coronary occlusion during hypothermia. Reserpine pretreatment markedly reduced both the catecholamines content of the left ventricle and the incidence of ventricular fibrillation. This protective action of reserpine can be counteracted by combined pretreatment with liothyronine sodium, although the catecholamines of the heart remained at a low level. Conversely, thyroidectomy and methimazole treatment also greatly reduced the incidence of ventricular fibrillation without significantly reducing cardiac catecholamines. These experiments reveal no correlation between the ventricular catecholamines content and the incidence of ventricular fibrillation. It is suggested that the protective effects of reserpine and thyroidectomy or antithyroid treatment might be due to depression of tissue metabolism.

ON THE RELATIONSHIP OF CATECHOLAMINES AND THYROID ACTIVITY TO VENTRICULAR FIBRILLATION DURING HYPOTHERMIA IN DOGS

1963 ◽  
Vol 41 (1) ◽  
pp. 361-367 ◽  
Author(s):  
D. R. Varma ◽  
R. A. Gillis ◽  
K. I. Melville
Keyword(s):  
Ventricular Fibrillation ◽  
Coronary Occlusion ◽  
Protective Action ◽  
Protective Effects ◽  
Thyroid Activity ◽  
Endogenous Catecholamines ◽  
Combined Pretreatment ◽  
Antithyroid Treatment ◽  
Relationship Of ◽  
The Relationship

The possible significance of endogenous catecholamines in the production of hypothermic ventricular fibrillation has been investigated.It is shown that in dogs under pentobarbitone anesthesia, neither iproniazid nor phenoxybenzamine pretreatment reduces the incidence of ventricular fibrillation following coronary occlusion during hypothermia. Reserpine pretreatment markedly reduced both the catecholamines content of the left ventricle and the incidence of ventricular fibrillation. This protective action of reserpine can be counteracted by combined pretreatment with liothyronine sodium, although the catecholamines of the heart remained at a low level. Conversely, thyroidectomy and methimazole treatment also greatly reduced the incidence of ventricular fibrillation without significantly reducing cardiac catecholamines. These experiments reveal no correlation between the ventricular catecholamines content and the incidence of ventricular fibrillation. It is suggested that the protective effects of reserpine and thyroidectomy or antithyroid treatment might be due to depression of tissue metabolism.

scholarly journals Presence of myocardial fibrotic or fat change on cardiac CT influences the width of distribution range of J waves in survivors of ventricular fibrillation

2021 ◽  
Vol 42 (Supplement_1) ◽  
Author(s):  
N Funabashi ◽  
K Nakamura ◽  
T Sasaki ◽  
S Naito ◽  
Y Kobayashi
Keyword(s):  
Ventricular Fibrillation ◽  
Cardiac Ct ◽  
Cardiac Computed Tomography ◽  
Myocardial Damage ◽  
Left Ventricular ◽  
Distribution Range ◽  
Inferior Wall ◽  
Funding Sources ◽  
Relationship Of ◽  
The Relationship

Abstract Background The distribution of J waves may correlate with left ventricular (LV) myocardial damage in survivors of ventricular fibrillation (VF). Purpose To determine the relationship of the distribution of J waves with presence of myocardial damage such as fibrotic or fat change on cardiac computed tomography (CT) in survivors of VF. Methods We conducted a retrospective analysis of 21 survivors of VF (17 males; mean age, 61±14 years) that were implanted with a cardioverter defibrillator and underwent cardiac CT. Results On ECG, 4 patients had atrial fibrillation and 15 had J waves. On CT, 13 patients had organized LV myocardial fibrotic and/or fat change in myocardium. The mean corrected QT interval was 453±30 and 429±48 msec in patients with and without myocardial fibrotic and/or fat change, respectively (P=0.182). The distribution of J waves was as follows: 5 had J waves in II, III and aVF leads (one had myocardial fibrotic and/or fat change) and 2 had J waves in III lead (one had myocardial fibrotic and/or fat change). One patient each had J waves in V1 lead; V1,2 leads; II, III, aVF and V1–3 leads; I, III, aVF and V1 leads; II, III, aVF, aVL and V1–6 leads; II, III, aVF and V4,5 leads; II, III, aVF and V2–5 leads; and III and aVF leads. The first one did not have myocardial fibrotic and/or fat change and the remaining 6 had myocardial fibrotic and/or fat change (Figure). If the J waves reached to ≥1 of 3 LV inferior wall leads (II, III, aVF leads) (N=13), 10 (77%) had LV myocardial fibrotic and/or fat change. If not (N=8), 3 (38%) had LV myocardial fibrotic and/or fat change (P=0.071). If the J waves reached ≥2 of 3 LV inferior wall leads (N=11), 9 (82%) had LV myocardial fibrotic and/or fat change. If not (N=10), 4 (40%) had LV myocardial fibrotic and/or fat change (P=0.049). If the J waves reached all three LV inferior wall leads (N=10), 8 (80%) had LV myocardial fibrotic and/or fat change. If not (N=11), 5 (46%) had LV myocardial fibrotic and/or fat change (P=0.104). Conclusions In survivors of VF, organized LV myocardial fibrotic and/or fat changes on cardiac CT correlate with a wider distribution range of J waves (reached to LV inferior wall leads). The distribution of J waves and the presence of myocardial fibrotic and/or fat change on CT may be useful to predict the occurrence of VF. FUNDunding Acknowledgement Type of funding sources: None. CT fibrosis in VF survivors J waves and fibrotic and/or fat change

The Relationship of Thyroid Activity to Lactation, Growth, and Sex in Sheep1

1956 ◽  
Vol 15 (3) ◽  
pp. 625-630 ◽  
Author(s):  
O. N. Singh ◽  
H. A. Henneman ◽  
E. P. Reineke
Keyword(s):  
Thyroid Activity ◽  
Relationship Of ◽  
The Relationship

THE RELATIONSHIP OF ALTERED THYROID ACTIVITY TO VARIOUS REPRODUCTIVE PHENOMENA IN GILTS

1958 ◽  
Vol 17 (1) ◽  
pp. 54-62 ◽  
Author(s):  
J. J. LUCAS ◽  
G. E. BRUNSTAD ◽  
S. H. FOWLER
Keyword(s):  
Fertilization Rate ◽  
Embryonic Mortality ◽  
Thyroid Activity ◽  
Fertilization Rates ◽  
The Third ◽  
Altered Thyroid ◽  
Relationship Of ◽  
The Relationship ◽  
Basal Ration ◽  
Duration Of Gestation

SUMMARY Three groups of fifteen Palouse gilts each were used to test the effects of altered thyroid activity on ovulation and fertilization rates and embryonic mortality in swine. Two groups received 0·15% thiouracil and 0·0123% thyroprotein, respectively, in a basal ration, and the third served as controls. All gilts were assigned to treatment sets at first oestrus and were bred to fertile boars at second oestrus. One-third of the gilts in each group were slaughtered 12–24 hr after the end of second oestrus, one-third slaughtered 25 days post coitum and the remainder allowed to farrow. An analysis of variance revealed no significant differences between groups for: ovulation rate, fertilization rate, embryonic mortality during the first 25 days of gestation, number of normal embryos at 25 days post coitum, or number of pigs born alive. A significant increase in the duration of gestation was found for thiouracil-treated females. Pigs born to thyroproteinsupplemented mothers were significantly heavier at birth than pigs born to thiouracil-treated mothers. Under the conditions of this experiment, X2 analysis indicated that thiouracil produced a highly significant embryonic mortality during gestation from the 25th day of pregnancy until farrowing. Thyroprotein treatment tended to lower embryonic mortality during the same period.

Regional expansion during myocardial ischemia predicts ventricular fibrillation and coronary reocclusion

1998 ◽  
Vol 274 (5) ◽  
pp. H1767-H1775 ◽  
Author(s):  
José A. Barrabés ◽  
David Garcia-Dorado ◽  
Miguel A. González ◽  
Marisol Ruiz-Meana ◽  
Julia Solares ◽  
...  
Keyword(s):  
Ventricular Fibrillation ◽  
Coronary Occlusion ◽  
Independent Predictor ◽  
Multiple Logistic Regression Analysis ◽  
Contractile Dysfunction ◽  
Reperfusion Arrhythmias ◽  
Ischemic Region ◽  
Coronary Ligation ◽  
Intimal Injury ◽  
The Relationship

Primary ventricular fibrillation (VF) complicating acute myocardial infarction is associated with occluded infarction-related arteries. The relationship between VF during ischemia and spontaneous coronary reocclusion was analyzed in 48 anesthetized pigs submitted to 48 min of coronary ligation and 6 h of reflow. Reocclusion was associated with ischemic VF (6 of 11 animals with VF but only 6 of 37 without it had reocclusion) but not with reperfusion arrhythmias, the size of the ischemic area, the magnitude of electrocardiogram changes or contractile dysfunction during ischemia, or the severity of intimal injury at the occlusion site. The increase in end-diastolic length in the ischemic region during coronary occlusion was associated with ischemic VF (15 min after occlusion, end-diastolic length was 116 ± 2 and 111 ± 1% of baseline in animals with or without presenting subsequent VF, respectively) and was retained by multiple logistic regression analysis as the only independent predictor of ischemic VF and reocclusion. Thus ischemic VF is strongly associated with an increased rate of spontaneous coronary reocclusion during subsequent reperfusion. Acute expansion of ischemic myocardium appears as a prominent determinant of both ischemic VF and reocclusion.

The relationship of the scleractinian corals to the rugose corals

Paleobiology ◽  
1980 ◽  
Vol 6 (02) ◽  
pp. 146-160 ◽  
Author(s):  
William A. Oliver
Keyword(s):  
Critical Points ◽  
Scleractinian Corals ◽  
Convincing Evidence ◽  
Early Triassic ◽  
Rugose Corals ◽  
History Of ◽  
The Subject ◽  
Relationship Of ◽  
The Relationship ◽  
Biologic Factors

The Mesozoic-Cenozoic coral Order Scleractinia has been suggested to have originated or evolved (1) by direct descent from the Paleozoic Order Rugosa or (2) by the development of a skeleton in members of one of the anemone groups that probably have existed throughout Phanerozoic time. In spite of much work on the subject, advocates of the direct descent hypothesis have failed to find convincing evidence of this relationship. Critical points are:(1) Rugosan septal insertion is serial; Scleractinian insertion is cyclic; no intermediate stages have been demonstrated. Apparent intermediates are Scleractinia having bilateral cyclic insertion or teratological Rugosa.(2) There is convincing evidence that the skeletons of many Rugosa were calcitic and none are known to be or to have been aragonitic. In contrast, the skeletons of all living Scleractinia are aragonitic and there is evidence that fossil Scleractinia were aragonitic also. The mineralogic difference is almost certainly due to intrinsic biologic factors.(3) No early Triassic corals of either group are known. This fact is not compelling (by itself) but is important in connection with points 1 and 2, because, given direct descent, both changes took place during this only stage in the history of the two groups in which there are no known corals.

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