ABSTRACT
Anti-arrhythmic effects of captopril (Cap) were studied in the anesthetized pigs using a reversible balloon catheter. Results showed that Cap did not exert any influence on the weight percentage of ischemic area to the whole left ventricle, on the levels of serum creatine kinase (CK) and creatine kinase isozyme (CK-MB), nor on the incidence and duration of transient and persistent tachycardia, but reduced the incidence of ventricular fibrillation (2/12, 1/12 in high-dose group pigs treated with Cap 6 mg.kg-1 in the first 10 min, 25 micrograms.kg-1.min-1 in the later 90 min and 12/21, 11/21 in control group treated with normal saline through the occlusion and reperfusion periods, respectively, P < 0.05). It was suggested that Cap did not exhibit direct (or non-specific, if any) effects on anti-arrhythmias.
Subject(s)
Anti-Arrhythmia Agents/therapeutic use , Captopril/therapeutic use , Myocardial Reperfusion Injury/complications , Ventricular Fibrillation/prevention & control , Animals , Anti-Arrhythmia Agents/pharmacology , Captopril/pharmacology , Creatine Kinase/blood , Isoenzymes , SwineABSTRACT
Acute myocardial ischemia and reperfusion in 49 young pigs were produced by balloon occlusion of the left anterior descending coronary artery. Alternations of ST segment and T wave (STTA) were detected in 33 pigs during ischemia. They started at 30 seconds to 14 minutes (mean 5.4 +/- 4.1 minutes) after occlusion and maintained for 4.0 +/- 3.4 minutes. The start and end of STTA might be gradual or abrupt. Abrupt STTA provoked by ventricular premature beat (VPB), and might be reset by VPB and short run of non-sustained repetitive ventricular firing. In leads V1 and V4 simultaneously recorded, STTA showed concordant in most cases and the discordant alternation was transient STTA was a significant discriminator in identifying cases in whom ventricular fibrillation or tachcardia was inducible in acute myocardial ischemia (P < 0.01). We conclude that STTA may provide a non-invasion measure of cardiac electrical stability during acute myocardial ischemia.
Subject(s)
Electrocardiography , Myocardial Ischemia/physiopathology , Animals , Myocardial Ischemia/complications , Myocardial Reperfusion Injury/physiopathology , Swine , Ventricular Fibrillation/etiology , Ventricular Fibrillation/physiopathologySubject(s)
Heart Block/physiopathology , Heart Conduction System/physiopathology , Adult , Aged , Electrocardiography , Electrophysiology , Female , Humans , Male , Middle Aged , Neural ConductionABSTRACT
W.P. occurring at sites other than A-V junctional area are reported. Some of the cases are rather rare. His bundle electrography may be the best method in discovering the site of block, but the using of conventional ECG is also able to detect a correct diagnosis. Clinical significance are discussed, some are innocent, some are related to serious heart disease. Thorough examination is necessary before arriving at any conclusion.
