Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0042510 (ventricular fibrillation)
 10,091 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Creatine kinase BB isoenzyme (CK-BB) was detected intraoperatively in 22 of 25 patients undergoing aortocoronary bypass surgery, both in the coronary sinus and in the mixed venous blood. In a group of 10 patients in whom selective intracavitary profound hypothermic arrest was used, CK-BB values were lower than in another group of 10 patients, in whom controlled ventricular fibrillation with moderate total body hypothermia was instituted. This latter group also had higher levels of CK-MB. Patients who developed acute myocardial infarction immediately prior to or during the surgical intervention had the highest CK-BB values. This enzyme appeared as early as 15 minutes after the institution of cardiopulmonary bypass and disappeared within 6 hours. It is considered that part of the BB isoenzyme in serum of patients undergoing heart surgery is of myocardial origin.
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PMID:Detection of creatine kinase BB isoenzyme in sera of patients undergoing aortocoronary bypass surgery. 30 Jun 59

In the isolated working rat heart model, we studied metabolic and hemodynamic effects of 5- and 30-min global ischemia followed by reperfusion and assessed the potentially beneficial effect of captopril 80 micrograms/ml added throughout the experiment. Creatine kinase (CK) and catecholamines were measured in coronary effluent. De novo eicosanoids (prostaglandin E2) synthesis was assessed in endocardial explants. Hemodynamic alterations occurred after 30-min ischemia and were reflected most dramatically by a reduction in cardiac output (CO 72 +/- 10% of baseline values in captopril vs. 68 +/- 16% in controls) without significant differences as a result of treatment. Captopril shortened reperfusion ventricular fibrillation (VF) duration (6.9 +/- 1.2 vs. 13.6 +/- 8.7 min, p less than 0.05) but had no effect on VF incidence. No differences occurred in norepinephrine (NE) outflow, whereas total CK release was greater in controls. Five controls versus none of the treated hearts (p less than 0.05) released trace amounts of epinephrine during reperfusion. Increased de novo PGE2 synthesis was demonstrated after 5-min I (465 +/- 168 vs. 238 +/- 75 pg/100 mg tissue per hour, p less than 0.01). Captopril stimulated production of PGE2 in normoxic hearts (p less than 0.02), but the difference was no more apparent in ischemic hearts. We conclude that captopril produces some biochemical and electrophysiologic evidence of myocardial salvage, but these effects are not sufficient to induce hemodynamic improvement after global ischemia and reperfusion.
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PMID:Effects of captopril on metabolic and hemodynamic alterations in global ischemia and reperfusion in the isolated working rat heart. 137 8

The effects of the converting enzyme inhibitor captopril on the susceptibility of the heart to ventricular arrhythmias following ischemia, both in vitro and in vivo, were studied. In isolated rat hearts, captopril, administered either before or at the end of ischemia, reduced ventricular fibrillation upon reperfusion after 15 minutes of local ischemia. Reduction of purine overflow, improvement in contractility, and increase in coronary blood flow occurred concomitantly. In vivo, a closed-chest pig model was used to determine the effects of captopril, administered at the end of ischemia and continued orally, on the susceptibility to ventricular arrhythmias during the chronic phase of myocardial infarction. Myocardial ischemia was induced by 60-minute inflation of a balloon catheter in the left anterior descending coronary artery. Upon reperfusion, an accelerated idioventricular rhythm occurred, both in 10 untreated and in 10 captopril-treated animals. Creatine kinase levels during the reperfusion period were significantly lower after captopril treatment. Two weeks after the short-term experiments, monomorphic ventricular tachycardia could be induced with programmed electrical stimulation in six of eight surviving untreated pigs. In contrast, in none of the six surviving captopril-treated animals was ventricular tachycardia inducible. Thus, early intervention with captopril during the development phase of myocardial infarction may have beneficial effects on the subsequent development of ventricular arrhythmias. Salvage of ischemic myocardium, improvement in ventricular function, beneficial effects on coronary flow, and decreased activity of the sympathetic nervous system may all contribute.
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PMID:Protective effects of captopril against ischemia/reperfusion-induced ventricular arrhythmias in vitro and in vivo. 306 1

The effect of oxygenation (100% oxygen) of the St. Thomas' Hospital cardioplegic solutions No. 1 (MacCarthy) and No.2 (Plegisol, Abbott Laboratories, North Chicago, Ill.) was examined in the isolated working rat heart subjected to long periods (3 hours for studies with solution No. 1 and 4 hours for studies with solution No. 2) of hypothermic (20 degrees C) ischemic arrest with multidose (every 30 minutes) cardioplegic infusion. At the aortic infusion point the oxygen tension of the oxygenated solutions (measured at 20 degrees C) was in the range of 320 to 560 mm Hg whereas that of the nonoxygenated solutions was less than 150 mm Hg. Twenty hearts (10 oxygenated and 10 nonoxygenated) were studied for each solution. The studies with solution No. 1 demonstrated that oxygenation led to a significant (p less than 0.05) reduction in the incidence of persistent ventricular fibrillation during postischemic reperfusion. Oxygenation of the cardioplegic solution also improved postischemic functional recovery so that the recovery of aortic flow was improved from 18.7% +/- 8.9% (of its preischemic control level) in the nonoxygenated group to 54.6% +/- 6.6% in the oxygenated group (p less than 0.025). Creatine kinase leakage was also significantly reduced from 27.5 +/- 4.8 to 9.9 +/- 0.6 IU/15 min/gm dry weight (p less than 0.005). Studies with solution No. 2 indicated that protection was better than with solution No. 1, even in the absence of oxygenation. A better degree of functional recovery was obtained after 4 hours of arrest with solution No. 2 than that obtained after only 3 hours of arrest with solution No. 1, and persistent ventricular ventricular fibrillation was never observed with solution No. 2. However, despite the superior performance with solution No. 2, further improvements could be obtained by oxygenation, with that time from the onset of reperfusion to the return of regular sinus rhythm being reduced from 55 +/- 8 to 35 +/- 2 seconds (p less than 0.01), postischemic recovery of aortic flow increasing from 59.8% +/- 7.4% to 85.7% +/- 2.5% (p less than 0.005), and creatine kinase leakage being reduced from 38.1 +/- 7.3 to 16.2 +/- 1.5 IU/15 min/gm dry weight (p less than 0.005). It is concluded that oxygenation of the St. Thomas' Hospital cardioplegic solutions improves their ability to protect the heart against long periods of ischemia and that this is manifested by improved postischemic electrical stability, functional recovery, and reduced creatine kinase leakage.
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PMID:Improved myocardial protection by oxygenation of St. Thomas' Hospital cardioplegic solutions. Studies in the rat. 333 23

Two commercially available formulations of St. Thomas' Hospital cardioplegic solutions, known as No. 1 (MacCarthy) and No. 2 (Plegisol, Abbott Laboratories, North Chicago, Ill.), were compared in the isolated working rat heart subjected to a long period (3 hours) of hypothermic ischemic arrest with multidose infusion. Solution No. 2 was found to be superior in nearly all respects. Of the 10 hearts infused with solution No. 1, persistent ventricular fibrillation during postischemic reperfusion occurred in six. Two of the six hearts, still in fibrillation after 15 minutes of reperfusion, were returned to regular rhythm by electrical defibrillation but failed to maintain an output. In contrast, in the 10 hearts infused with solution No. 2, ventricular fibrillation was short lasting (p less than 0.01). In comparing mechanical function in all hearts returning to regular rhythm (either spontaneously or after electrical defibrillation), the mean postischemic recoveries for aortic flow and rate of rise of left ventricular pressure (expressed as a percentage of its preischemic control) were significantly greater with solution No. 2 than with solution No. 1 (74.3% +/- 6.9% compared with 18.7% +/- 8.9%, p less than 0.01, and 98.0% +/- 6.0% compared with 63.0% +/- 9.0%, p less than 0.005, respectively). Creatine kinase leakage tended to be lower in hearts infused with solution No. 2 (19.7 +/- 4.7 IU/15 min/gm dry weight as opposed to 27.5 +/- 4.7 IU/15 min/gm dry weight), although this difference did not achieve a level of statistical significance. Consideration is given to the differences in formulation between solutions, which might account for the improved performance with solution No. 2, and it is concluded that the lower calcium content of solution No. 2 (1.2 as opposed to 2.4 mmol/L) is likely to be the most important factor.
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PMID:The St. Thomas' Hospital cardioplegic solution. A comparison of the efficacy of two formulations. 380 99

The effects of the calcium antagonist, diltiazem, on myocardial injury during ischemia and reperfusion were studied both in vitro, in the isolated rat heart, and in vivo, in a closed-chest pig model. In the isolated rat heart, administration of diltiazem before or at the onset of ischemia resulted in a dose-dependent reduction of the incidence and duration of ventricular fibrillation. This reduction was associated with a dose-dependent reduction in overflow of ATP catabolites (adenosine, inosine, hypoxanthine and xanthine). Both changes were significant at concentrations of 3 X 10(-7) M diltiazem and higher. When 3 X 10(-7) M diltiazem was administered upon reperfusion no effect on the incidence of ventricular fibrillation and on ischemia induced total purine overflow was observed. However, the duration of ventricular fibrillation and purine overflow at 5 min after reperfusion were significantly reduced. In the pig experiments all untreated animals (n = 8) showed accelerated idioventricular rhythm (AIVR) upon reperfusion which lasted for 22 +/- 5 min after which sinus rhythm returned. Only two out of five treated animals (450 micrograms/kg/2 h) had an AIVR. Upon reperfusion both groups showed a substantial rise in noradrenaline concentration in the coronary sinus blood, but after 5 min this was significantly less in the treated group. Creatine kinase-kinetics were not altered by diltiazem, but the maximum creatine kinase level was significantly reduced. Within 4 days after the acute experiment 50% of the untreated animals died suddenly, whereas no sudden deaths occurred in the diltiazem group (P less than 0.05). Seven days after the acute experiment, sustained ventricular tachycardia could be induced with programmed electrical stimulation in three out of four surviving untreated pigs. In none of the diltiazem treated pigs was ventricular tachycardia inducible. The results of this study show that the calcium antagonist diltiazem can beneficially influence the events during ischemia and during reperfusion, both in vitro and in vivo; this benefit is associated with a reduction of ATP catabolism, creatine kinase release and noradrenaline overflow. Furthermore, diltiazem reduces electrical instability in the chronic phase of myocardial infarction.
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PMID:Effects of diltiazem on reperfusion-induced arrhythmias in vitro and in vivo. 382 Mar 17

Creatine kinase (CK) and its brain-specific isoenzyme (CK-BB), neuron-specific enolase (NSE), neural cell adhesion molecule (NCAM) and the ions sodium, potassium, chloride and calcium were measured both in CSF and serum and inorganic phosphate in CSF in order to assess their prognostic value in total brain ischemia due to cardiac arrest. The samples were collected at 4, 28 and 76 h after resuscitation. Twenty consecutive patients resuscitated from ventricular fibrillation or asystole were included in the study. Nine of the patients recovered consciousness (recovered) but eleven remained comatose (disabled). The follow-up period was 2 years after which only one patient was still alive. The earliest statistically significant differences between neurologically recovered and disabled patient groups were seen in CSF inorganic phosphate (P = 0.030) already at 4 h and CK-BB (P = 0.046) and NSE (P = 0.020) activity at 28 h. Later, at 76 h after the resuscitation CSF NSE differentiated the groups most clearly (P = 0.014). The values were higher in the disabled patients. A negative correlation between CSF parameters and Glasgow Coma scores was also seen at these timepoints. Statistically significant differences between the groups were seen in both CSF and blood pCO2, pO2, base excess (BE) and actual bicarbonate (HCO3-). CSF or serum NCAM has no prognostic value in anoxic-ischemic coma. The results suggest that in CSF CK-BB and NSE are useful prognostic indicators of hypoxic brain injury when measured 28-76 h after cardiac arrest whereas blood samples have no prognostic value.
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PMID:CSF and serum brain-specific creatine kinase isoenzyme (CK-BB), neuron-specific enolase (NSE) and neural cell adhesion molecule (NCAM) as prognostic markers for hypoxic brain injury after cardiac arrest in man. 850 98

Coenzyme Q10 (CoQ10, ubiquinone) has been shown to be protective against myocardial ischemia/reperfusion induced injury. The purpose of this study was to investigate the effect of CoQ10 added to cold cristalloid cardioplegia on hypothermic ischemia and normothermic reperfusion using an isolated working rat heart. Hearts (n = 6-9/group) from male Wistar rats were aerobically (37 degrees C) perfused (20 min) with bicarbonate buffer. This was followed by a 3-min infusion of St. Thomas' Hospital cardioplegic solution containing various concentrations of CoQ10 (0, 1, 3, 6, 12, and 58 mumol/L). Hearts were then subjected to 180 min of hypothermic (20 degrees C) global ischemia and 35 min of normothermic (37 degrees C) reperfusion (15 min Langendorff, 20 min working). Ventricular fibrillation (Vf) upon reperfusion was irreversible in the 12 and 58 mumol/ L CoQ10 groups (4/6 and 3/6, respectively). In the hearts which Vf upon reperfusion was not irreversible, the percent recovery of aortic flow (%AF) was 43.3 +/- 5.4% (n = 9) in the control group versus 31.6 +/- 7.7% (n = 6), 38.0 +/- 12.0% (n = 6), 27.2 +/- 6.9% (n = 6), 31.3% (n = 2), and 30.4 +/- 14.2% (n = 3) in the 1, 3, 6, 12, and 58 mumol/L CoQ10 groups, respectively. Creatine kinase leakage during Langendorff reperfusion tended to be greater in the 12 and 58 mumol/L CoQ10 groups than in the control group. Thus, CoQ10 in the cold cristalloid cardioplegic solution induced irreversible Vf upon reperfusion and failed to improve functional recoveries following hypothermic global ischemia.
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PMID:[The effect of coenzyme Q10 and cold cristalloid cardioplegia on hypothermic global ischemia]. 896 87

Preconditioning is commonly induced by a brief ischemic insult; myocardial stretch can trigger this protection by an unknown mechanism. Myocardial stretch preconditions the in vivo canine heart; however, the existence of a stretch-induced protection in the rat heart remains unknown. The purpose of this study was to test this myocardial protection induced, in isolated working rat heart, by global ischemia and stretch initiated by a transient increase in the left ventricle (LV). Isolated rat hearts underwent 30 min of global ischemia followed by 30 min of reperfusion. Before this, hearts received a 15-min period of either no intervention (control; C), 5 min of global ischemia + 10 min of reperfusion (preconditioning; PC) or 5 min of stretch + 10 min with no intervention (stretch; S). Stretch was induced by a transient increase in LV preload from 5 to 20 cm H2O. LV work started under a afterload of 80 cm H2O. Control, PC, and S hearts received either no drug (untreated) or staurosporine (50 nM), a protein kinase C inhibitor, before the "preconditioning" period. Creatine kinase (CK) release, ventricular fibrillation during reperfusion, and postischemic recovery of contractile function (aortic flow) were the end points of the study. In the S group, the abrupt increase in preload resulted in a significant increase of aortic flow (42 +/- 2 to 47 +/- 2 ml/min; p < 0.05). During the 30-min reperfusion period, control hearts displayed a poor recovery of contractile functions (8 +/- 3 ml/min, 30 min after reflow, versus 40 +/- 2 ml/min at baseline; p < 0.05). Both untreated PC and S groups exhibited a significant reduction in CK release, incidence of ventricular fibrillation (55% of control hearts developed persistent VF vs. 6% in both the PC and S groups), and postischemic dysfunction during reperfusion (p < 0.05 vs. control). Staurosporine prevented these beneficial effects in PC and S groups. Our study suggests that myocardial protection can be induced by stretch in the isolated working rat heart, likely through activation of protein kinase C. In conclusion, our results show that ischemic preconditioning and stretch had comparable favorable effect on functional recovery after a sustained ischemic insult in the isolated rat heart.
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PMID:Beneficial actions of preconditioning and stretch on postischemic contractile function of isolated working rat heart: effects of staurosporine. 926 46

It has been suggested that QT dispersion (maximal minus minimal QT interval calculated on a standard 12-lead electrocardiogram) could reflect regional variations of ventricular repolarization and could provide a substrate for reentry ventricular arrhythmias. The present study evaluates QT dispersion in patients with acute myocardial infarction, assessing its relation with early severe ventricular arrhythmias and some clinical features. Three hundred three patients with acute myocardial infarction and a control group of 297 healthy subjects were studied. QT and QTc dispersion were determined on the electrocardiogram taken after 12 hours and on days 3 and 10 after symptoms onset and on the electrocardiogram taken in the control group. The average values of QT and QTc dispersions (ms) were as follows: 70.5 +/- 42.5-87 +/- 45.6 (12th hour), 66.7 +/- 37.6-76.8 +/- 43.6 (day 3), 68.8 +/- 42.7-76.8 +/- 42.8 (day 10), versus 43 +/- 13.2-53.9 +/- 16.2 (control group). There were statistically significant differences between QT and QTc dispersion recorded in normal subjects and in each of the three electrocardiograms taken in patients with infarction. A greater QT dispersion was recorded in patients with anterior infarction (78.9 +/- 38.5 vs 64.9 +/- 42.8 in inferior/lateral infarction). In the first 3 days QT dispersion was not different in patients treated and untreated with thrombolysis, whereas on day 10 it was greater in untreated patients (74.9 +/- 45.3 vs 60.5 +/- 37.2). Creatine kinase peak level did not influence QT dispersion. In the first 72 hours of infarction, 37 patients developed ventricular fibrillation or sustained ventricular tachycardia. Higher early values of QT and QTc dispersion were found in patients who developed severe ventricular arrhythmias (107.8 +/- 62 and 124.8 +/- 67.5 ms) than in patients without serious arrhythmias (62.9 +/- 32.2 and 80.1 +/- 37.9 ms). These data suggest that: (1) QT dispersion increased during acute myocardial infarction. (2) The values were higher in the early hours and fell late after infarction with thrombolysis. (3) Greater QT dispersion is associated with severe ventricular arrhythmias.
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PMID:QT dispersion and early arrhythmic risk during acute myocardial infarction. 1008


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