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.

Ventricular fibrillation during acute coronary occlusion is related to the dilation of the ischemic region

2002 ◽  
Vol 97 (6) ◽  
pp. 445-451 ◽  
Author(s):  
José A. Barrabés ◽  
David Garcia-Dorado ◽  
Ferran Padilla ◽  
Luis Agulló ◽  
Lourdes Trobo ◽  
...  
Keyword(s):  
Ventricular Fibrillation ◽  
Coronary Occlusion ◽  
Ischemic Region ◽  
Acute Coronary Occlusion

Distension of the Ischemic Region Predicts Increased Ventricular Fibrillation Inducibility Following Coronary Occlusion in Swine

2013 ◽  
Vol 66 (3) ◽  
pp. 171-176 ◽  
Author(s):  
José A. Barrabés ◽  
Jaume Figueras ◽  
Jaume Candell-Riera ◽  
Luis Agulló ◽  
Javier Inserte ◽  
...  
Keyword(s):  
Ventricular Fibrillation ◽  
Coronary Occlusion ◽  
Ischemic Region

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.

Glycogen depletion contributes to ischemic preconditioning in the rat heart in vivo

1996 ◽  
Vol 271 (6) ◽  
pp. H2283-H2289 ◽  
Author(s):  
P. H. McNulty ◽  
A. Darling ◽  
J. M. Whiting
Keyword(s):  
Infarct Size ◽  
Ischemic Preconditioning ◽  
Coronary Occlusion ◽  
Glycogen Depletion ◽  
Risk Area ◽  
Reperfusion Arrhythmias ◽  
Glycogen Concentration ◽  
Ischemic Region ◽  
Lactate Formation

Ischemic preconditioning depletes the myocardium of glycogen, thus blunting lactic acidosis during subsequent episodes of ischemia. Preconditioning also protects against reperfusion arrhythmias and infarction. To test whether glycogen depletion is necessary for this ischemic tolerance, we preconditioned two groups of intact rats with a series of 3-min coronary artery occlusions. In one group, preconditioning lowered the glycogen concentration of the ischemic region by approximately 50% (24.9 +/- 2.5 to 12.5 +/- 1.8 mumol/g; P < 0.01). In the other, the heart was first loaded with glycogen via glucose-insulin infusion so that preconditioning merely reduced its glycogen concentration back to normal physiological levels. Compared with nonpreconditioned control rats, preconditioned rats with both normal and subnormal glycogen concentrations were protected from reperfusion arrhythmias after a 6-min coronary occlusion (incidence: control rats, 100%; normal glycogen rats, 11%; reduced glycogen rats, 11%). In contrast, only rats with subnormal glycogen concentration after preconditioning exhibited reduced lactate formation and infarct size after a 45-min coronary occlusion [infarct size (percentage of risk area): control rats, 53 +/- 10%; normal glycogen rats, 50 +/- 16%, P = not significant; subnormal glycogen rats, 18 +/- 10%, P < 0.01]. Thus, in the intact rat, myocardial glycogen depletion appears to be necessary for the infarct-limiting, but not for the antiarrhythmic, effects of ischemic preconditioning.

Exploring the Potential Impact of Sentence-Level Comprehension and Sentence-Level Fluency on Deaf Students' Passage Comprehension

2020 ◽  
Vol 63 (7) ◽  
pp. 2281-2292
Author(s):  
Ying Zhao ◽  
Xinchun Wu ◽  
Hongjun Chen ◽  
Peng Sun ◽  
Ruibo Xie ◽  
...  
Keyword(s):  
Independent Predictor ◽  
Vocabulary Knowledge ◽  
Group Differences ◽  
Regression Analyses ◽  
Deaf Students ◽  
Mediating Role ◽  
Sentence Level ◽  
Mediating Mechanisms ◽  
Potential Impact ◽  
The Relationship

Purpose This exploratory study aimed to investigate the potential impact of sentence-level comprehension and sentence-level fluency on passage comprehension of deaf students in elementary school. Method A total of 159 deaf students, 65 students ( M age = 13.46 years) in Grades 3 and 4 and 94 students ( M age = 14.95 years) in Grades 5 and 6, were assessed for nonverbal intelligence, vocabulary knowledge, sentence-level comprehension, sentence-level fluency, and passage comprehension. Group differences were examined using t tests, whereas the predictive and mediating mechanisms were examined using regression modeling. Results The regression analyses showed that the effect of sentence-level comprehension on passage comprehension was not significant, whereas sentence-level fluency was an independent predictor in Grades 3–4. Sentence-level comprehension and fluency contributed significant variance to passage comprehension in Grades 5–6. Sentence-level fluency fully mediated the influence of sentence-level comprehension on passage comprehension in Grades 3–4, playing a partial mediating role in Grades 5–6. Conclusions The relative contributions of sentence-level comprehension and fluency to deaf students' passage comprehension varied, and sentence-level fluency mediated the relationship between sentence-level comprehension and passage comprehension.

President Obama and the Emergence of Islamophobia in Mass Partisan Preferences

2021 ◽  
pp. 106591292110072
Author(s):  
Michael Tesler
Keyword(s):  
Theoretical Basis ◽  
Independent Predictor ◽  
Survey Experiment ◽  
President Obama ◽  
Significant Independent Predictor ◽  
Cross Sectional ◽  
Panel Surveys ◽  
Voter Preferences ◽  
Nationally Representative ◽  
The Relationship

This article argues that the unusually large and persistent association between Islamophobia and opposition to President Obama helped make attitudes about Muslims a significant, independent predictor of Americans’ broader partisan preferences. After detailing the theoretical basis for this argument, the article marshals repeated cross-sectional data, two panel surveys, and a nationally representative survey experiment, to test its hypotheses. The results from those analyses show the following: (1) attitudes about Muslims were a significantly stronger independent predictor of voter preferences for congress in 2010–2014 elections than they were in 2004–2008; (2) attitudes about Muslims were a significantly stronger independent predictor of mass partisanship during Obama’s presidency than they were beforehand; and (3) experimentally connecting Obama to Democratic congressional candidates significantly increased the relationship between anti-Muslim sentiments and Americans’ preferences for Republican congressional candidates. The article concludes with a discussion of the implications of these results for American politics in the Trump era.

Blood pressure, heart rate, and adrenal catecholamines prior to ventricular fibrillation

1961 ◽  
Vol 201 (1) ◽  
pp. 109-111 ◽  
Author(s):  
Noel M. Bass ◽  
Vincent V. Glaviano
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Blood Flow ◽  
Ventricular Fibrillation ◽  
Coronary Occlusion ◽  
Marked Decrease ◽  
Mean Blood Pressure ◽  
Plasma Adrenaline ◽  
Acute Coronary Occlusion ◽  
Before And After

Heart rate, mean blood pressure, adrenal blood flow, and adrenal plasma adrenaline and noradrenaline were compared before and after ligation of the anterior descending coronary artery in dogs anesthetized with chloralose. One group of 12 dogs responded to acute coronary occlusion with a sudden and marked decrease in mean blood pressure (mean, 31%) and heart rate (mean, 18%) followed by an early onset (mean, 227 sec) of ventricular fibrillation. Another group of nine dogs responded with slight decreases in mean blood pressure (mean, 13%) and heart rate (mean, 5%), during which time ventricular fibrillation occurred late (mean, 30 min) or not at all. While the two groups were statistically different in mean blood pressure and heart rate, the minute output of adrenal catecholamines in either group was not found to be related to the early or late occurrence of ventricular fibrillation.

External Ventricular Drain Infection

2007 ◽  
Vol 107 (1) ◽  
pp. 248 ◽  
Author(s):  
George K. C. Wong ◽  
Wayne W. S. Poon
Keyword(s):  
Major Trauma ◽  
Independent Predictor ◽  
External Ventricular Drain ◽  
Significant Risk ◽  
Significant Risk Factor ◽  
External Ventricular Drainage ◽  
Infection Rates ◽  
The Mean ◽  
The Relationship ◽  
Shed Light

Object The authors explored the relationship among the duration of external ventricular drainage, revision of external ventricular drains (EVDs), and cerebrospinal fluid (CSF) infection to shed light on the practice of electively revising these drains. Methods In a retrospective study of 199 patients with 269 EVDs in the intensive care unit at a major trauma center in Australasia, the authors found 21 CSF infections. Acinetobacter accounted for 10 (48%) of these infections. Whereas the duration of drainage was not an independent predictor of infection, multiple insertions of EVDs was a significant risk factor. Second and third EVDs in previously uninfected patients were more likely to become infected than first EVDs. An EVD infection was initially identified a mean of 5.5 ±0.7 days postinsertion (standard error of the mean); these data—that is, the number of days—were normally distributed. Conclusions This pattern of infection is best explained by EVD-associated CSF infections being acquired by the introduction of bacteria on insertion of the drain rather than by subsequent retrograde colonization. Elective EVD revision would be expected to increase infection rates in light of these results, and thus the practice has been abandoned by the authors' institution.

Sign in / Sign up

Export Citation Format

Share Document