Ventricular Arrhythmias and K+ Transfer during Myocardial Ischemia and Intervention with Procaine Amide, Insulin, or Glucose Solution*

Regan, Timothy J.; Harman, Maureen A.; Lehan, Patrick H.; Burke, William M.; Oldewurtel, Henry A.

doi:10.1172/jci105657

Cited by 118 publications

(17 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The relevance of the potassium ion to the occurrence of lethal ventricular arhythmias soon after the production of acute myocardial ischaemia has been the subject of a number of experimental studies. Some authors have deduced a causal relationship between cumulative potassium loss and the incidence of ventricular arrhythmias in the early stages of experimental myocardial infarction (Harris, Bisteni, Russell, Brigham & Firestone, 1954;Regan, Harman, Lehan, Burke & Oldewurtel, 1967) while others have failed to show any relationship (Wexler & Patt, 1960;Thomas et al, 1970).…”

Section: Discussionmentioning

confidence: 99%

ANTIARRHYTHMIC, HAEMODYNAMIC AND METABOLIC EFFECTS OF 3α‐AMINO‐5α‐ANDROSTAN‐2β‐OL‐17‐ONE HYDROCHLORIDE IN GREYHOUNDS FOLLOWING ACUTE CORONARY ARTERY LIGATION

Marshall

Parratt

1975

British J Pharmacology

View full text Add to dashboard Cite

1The antiarrhythmic, haemodynamic and metabolic effects of a new amino steroid, ORG6001, have been investigated in experimental acute myocardial infarction in anaesthetized greyhounds. 2 ORG6001 administered either intravenously (1-10 mg/kg) or orally (50 mg/kg) significantly reduced the incidence of ventricular ectopic beats in the first 30 min after ligation of the left anterior descending coronary artery. 3 In dogs pretreated with ORG600 1, metabolic changes indicative of myocardial ischaemia (lactate production and potassium efflux) were less marked than those occurring in control animals. 4 Antiarrhythmic doses of ORG6001 caused only minimal transient haemodynamic effects. 5 These results suggest that ORG6001 may possess distinct advantages over presently-used antiarrhythmic drugs in the prevention and treatment of the early arrhythmias which occur after myocardial infarction.

show abstract

Section: Discussionmentioning

confidence: 99%

ANTIARRHYTHMIC, HAEMODYNAMIC AND METABOLIC EFFECTS OF 3α‐AMINO‐5α‐ANDROSTAN‐2β‐OL‐17‐ONE HYDROCHLORIDE IN GREYHOUNDS FOLLOWING ACUTE CORONARY ARTERY LIGATION

Marshall

Parratt

1975

British J Pharmacology

View full text Add to dashboard Cite

show abstract

“…The rationale suggested for using glucose or combinations of glucose, K, and insulin in treating myocardial infarction has been to supply adequate glucose to the heart, thereby obtaining energy from anaerobic breakdown of glucose (37,38,40), reverse potassium loss from the heart, and maintain membrane stability (41,42). It is known that glucose/insulin accelerates triglyceride formation (19) and decreases release of FFA from adipose tissue (43).…”

Section: Discussionmentioning

confidence: 99%

Effect of free fatty acids on myocardial function and metabolism in the ischemic dog heart

Kjekshus¹,

Mjøs²

1972

J. Clin. Invest.

160

View full text Add to dashboard Cite

A B S T R A C T Since elevation of plasma concentrations of free fatty acids (FFA) increases myocardial oxygen consumption without influencing mechanical performance in normal hearts, it was the purpose of this study to determine whether FFA would modify mechanical performance at limited oxygen supply. Left coronary blood flow was reduced by gradual clamping of a shunt from the left carotid artery until moderate ventricular dilatation supervened. Left ventricular systolic pressure (LVSP), its maximal rate of rise (dP/dt) and stroke volume (SV) were unchanged or slightly reduced. The ischelmia resulted in a decrease in myocardial oxygen consumption (MV02) from 9.7±+1.1 ml/min to 7.9±0.8 ml/min, and myocardial lactate uptake was reduced or reversed to excretion. Increasing the plasma concentrations of FFA from 359±47 iAEq/l to 3688±520 /Eq/l by intravenous infusion of a triglyceride emulsion and heparin resulted in further ventricular dilatation, accompanied by increased excretion of lactate. The ventricular decompensation and enhancement of anaerobic myocardial metabolism associated with increased uptake of FFA was not related to changes in coronary flow, MV02, or LVSP. dP/dt and SV were virtually unchanged. Intravenous infusion of glucose/insulin, which lowered plasma concentrations of FFA, reversed ventricular dilatation and lactate excretion.The data support the hypothesis that high concentrations of FFA play a significant role in increasing myocardial oxygen requirement and thereby promote depression of contractility of the hypoxic heart in experimental animals.

show abstract

“…The evidence which implicates potassium as the agent most likely responsible for the biphasic alterations in CT observed during the course of ischemia is as follows: (a) Potassium is known to be released from ischemic myocardial cells after coronary artery occlusion (24)(25)(26). (b) The changes seen here in activation time in the ischemic porcine heart are identical to the changes in conduction time observed in the nonischemic but progressively hyperkalemic canine heart.…”

Section: Discussionmentioning

confidence: 55%

The QRS complex during myocardial ischemia. An experimental analysis in the porcine heart.

Holland¹,

Brooks²

1976

J. Clin. Invest.

169

View full text Add to dashboard Cite

A B S T R A C T Although ST segment deflections have been widely utilized as a means of assessing the degree of underlying ischemic injury, the relationship of QRS complex alterations to the ischemic process is poorly understood. In this study we made a beat-to-beat analysis of the QRS complex in terms of ventricular activation time (CT) and R wave voltage (V) in the acutely ischemic porcine myocardium and analyzed the relationship of these responses to changes in the area of ischemic involvement, altered myocardial energy demands, and plasma [K+]o levels.With the onset of ischemia the QRS complex underwent a specific and reproducible biphasic sequence with an initial decrease in CT and V indicating a transient increase in the conduction velocity of the ischemic tissue. Subsequently both CT and V returned briefly to control and then increased dramatically, now indicating a marked decrease in conduction velocity. The time when CT first began to increase (Tc) was shortened by enlarging the area of ischemia or after an inotropic intervention and was lengthened by decreasing the area of ischemia or with administration of propranolol. Moreover Tc was found to be inversely proportional to plasma [K+]o in the range 3.4-8.8 mM, above which the initial decrease in CT and V was no longer present.We conclude that this biphasic sequence of QRS alterations in early myocardial ischemia is attributable to a progressive leakage of potassium out of the ischemic cells which in turn alters both the time-course and transmural pathway of the activation process through the ischemic tissue. These changes are related to both inotropic state and the area of ischemic involvement. INTRODUCTIONAlthough ST segment deflections have been widely utilized as a means of assessing the degree of underlying ischemic injury (1, 2) the relationship of QRS complex alterations to the ischemic process is poorly understood. The casual observations of changes in R wave amplitude noticed by some ST segment investigators after coronary artery occlusion in the dog (3-5) as well as the more specific studies of , Scher (9), and Durrer and van der Tweel (10) in the dog and goat suggest that ischemic QRS complex alterations may bear characteristic temporal and/or spatial relationships to the underlying ischemic process.In the present study we have characterized the temporal sequence of QRS complex alterations during early myocardial ischemia in the intact porcine heart, their modification by changes in the area of ischemic involvement, and altered myocardial energy demands, as well as the important role of potassium in their genesis.

show abstract

Ventricular Arrhythmias and K+ Transfer during Myocardial Ischemia and Intervention with Procaine Amide, Insulin, or Glucose Solution*

Cited by 118 publications

References 22 publications

ANTIARRHYTHMIC, HAEMODYNAMIC AND METABOLIC EFFECTS OF 3α‐AMINO‐5α‐ANDROSTAN‐2β‐OL‐17‐ONE HYDROCHLORIDE IN GREYHOUNDS FOLLOWING ACUTE CORONARY ARTERY LIGATION

ANTIARRHYTHMIC, HAEMODYNAMIC AND METABOLIC EFFECTS OF 3α‐AMINO‐5α‐ANDROSTAN‐2β‐OL‐17‐ONE HYDROCHLORIDE IN GREYHOUNDS FOLLOWING ACUTE CORONARY ARTERY LIGATION

Effect of free fatty acids on myocardial function and metabolism in the ischemic dog heart

The QRS complex during myocardial ischemia. An experimental analysis in the porcine heart.

Contact Info

Product

Resources

About