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T Fazekas

Publications and source records attributed to T Fazekas.

At least 55 records · Page 3Linked to original sources
PubMed1994

Facilitation of reentry by lidocaine in canine myocardial infarction.

The authors studied the effects of lidocaine in 18 consecutive dogs with myocardial infarction 1 to 4 days after two-stage left anterior descending coronary artery ligation. Electrophysiologic testing was performed in anesthetized dogs after infarction with single-, double-, or triple-programmed extrastimuli or rapid bursts (3 beats at 240 to 420 beats/min) delivered to the right ventricular outflow tract. Inducibility of sustained monomorphic ventricular tachycardia after an intravenous bolus of lidocaine (3 to 6 mg/kg) was compared in the same animal to the premedicated state. In the control state, sustained monomorphic ventricular tachycardia was inducible in 6 of 18 dogs. After administration of lidocaine, electrically induced sustained monomorphic ventricular tachycardia was initiated in an additional nine dogs (which were previously noninducible; after lidocaine administration vs control p < 0.02). The antiarrhythmic agent induced further rate-dependent slowing of conduction in the periinfarction subepicardium, which at a critical value of rate and amount of conduction delay resulted in sustained reentrant monomorphic tachycardia. These results show that lidocaine has marked proarrhythmic action in this canine model of myocardial infarction, probably because of its depressant effect on injured cardiac tissue.

Animals↗
PubMed1994

Action of MgSO4 differs from moricizine and verapamil on ouabain-induced ventricular tachycardia in normomagnesemic conscious dogs.

We performed a comparative study to determine whether acute administration of MgSO4, moricizine, and verapamil to conscious dogs with normal plasma magnesium levels (0.75 +/- 0.06 mM) terminates ouabain-induced ventricular tachycardia (VT). This arrhythmia is dependent on triggered activity (TA) resulting from delayed afterdepolarizations (DADs). In animals with surgically induced complete atrioventricular (AV) block, monomorphic VT was induced by programmed ventricular stimulation during continuous intravenous (i.v.) infusion of ouabain. At the moment of drug administration, VT persisted for at least 20 min, while the rate was stable for at least 5 min. A single dose of MgSO4 (100 mg/kg i.v.) abolished only VTs with cycle lengths > or = 320 ms (335 +/- 10 ms); VTs with faster cycle lengths (300 +/- 20 ms) were merely slowed, although the increase in plasma magnesium levels was considerable and comparable in both groups (3.9 +/- 1.6 and 4.8 +/- 1.9 mM). In contrast, moricizine (2 mg/kg i.v.) and verapamil (0.5-1.0 mg/kg i.v.) terminated both fast and slow VTs. The cycle length of VT ranged from 280 to 320 ms (mean 300 +/- 15 ms) for moricizine and 260-330 ms (mean 300 +/- 25 ms) for verapamil.(ABSTRACT TRUNCATED AT 250 WORDS)

Action Potentials↗
PubMed1994

Facilitation of reentry by lidocaine in canine myocardial infarction.

Despite continuing controversies regarding its antiarrhythmic and antifibrillatory efficacy lidocaine is frequently used for the treatment of ventricular arrhythmias occurring in the early phase of acute myocardial infarction (MI). The authors studied the effects of lidocaine in 18 consecutive MI dogs 1-4 days (2.8 +/- 0.3 day) after the two-stage left anterior descending coronary artery (LAD) ligation and in 11 dogs, in which the LAD and the distal branches of the left circumflex artery was ligated 12-75 (mean 35) days prior to study. Electrophysiologic testing was performed in anesthetized post-infarction dogs using single, double or triple programmed extrastimuli or rapid bursts (3 beats at 240-420/min) delivered to the right ventricular outflow tract. Inducibility of SMVT (uniform QRS morphology lasting > 30 sec at a rate of > 250 beat/min) after an i.v. bolus of lidocaine (3-6 mg/kg) was compared in the same animal to the pre-drug state. During the control state, SMVT was inducible in 6/18 dogs. After the administration of lidocaine, electrically induced SMVT was initiated in additionally 9 dogs (which were previously non-inducible; post-lidocaine vs control p < 0.02). Sustained reentry was induced by 3 mg/kg lidocaine in 5 dogs (310 +/- 62 beat/min) and by 6 mg/kg in 4 (261 +/- 52 beat/min). In the 8 survivors of the chronic MI group, SMVT was inducible before lidocaine administration in one, but in 7 after lidocaine. The antiarrhythmic agent induced further rate-dependent slowing of conduction in the peri-infarction subepicardium, which at a critical value of rate and amount of conduction delay resulted in sustained reentrant monomorphic tachycardia. These results show that lidocaine has arrhythmogenic/proarrhythmic actions in these canine models of MI probably due to its depressant effect on moderately sick cardiac tissue. The 'modification' of the functional properties of the arrhythmia substrate by lidocaine can promote the formation of new reentrant pathways leading to manifest sustained ventricular reentry under electrophysiologic study.

Acute Disease↗
PubMed1993

[Laparoscopic cholecystectomy].

Traditional cholecystectomy has been the standard surgical treatment of the gallstone disease for more than 100 years. The technical development led to a new surgical procedure and its rapid acceptance. This is laparoscopic cholecystectomy. Its application is becoming widespread in therapy too. But most of the surgeons are lack of technical experiences in this field. Currently it restricts the indications those are anyway the same of standard cholecystectomy. Besides its many advantages, laparoscopic cholecystectomy has its own disadvantages and being an invasive procedure, there are possibilities of complications. The latest can be reduced by the adequate choice of patients, the careful learning of the operative technic and by turning to open surgery (conversion) when it is necessary. Its morbidity is nearly equal to complications of standard cholecystectomy, but mortality rate is lower (0.05-0.2%). Our morbidity of performed 300 laparoscopic cholecystectomies was 6.4%. We had no death. The hospitalization became as short as 4 days. Our early clinical results (90%) are the same of traditional cholecystectomy. Laparoscopic cholecystectomy as a new surgical procedure involves the efficiency of the standard cholecystectomy and the noninvasive endoscopic technic. Laparoscopic cholecystectomy performed by well trained surgeons is a safe surgical procedure, its early results are excellent and makes the choice of surgical treatment, used in bile surgery richer.

Acute Disease↗
PubMed1993

Magnesium and the heart: antiarrhythmic therapy with magnesium.

Magnesium is an essential transmembrane and intracellular modulator of the electrical activity of cardiac cells. This review provides an up-to-date consideration of the cellular and clinical electrophysiological role of magnesium. This ubiquitous element seems to be important from both the theoretical and clinical point of view, because magnesium salts (MgSO4, MgCl2) administered intravenously are particularly effective in those arrhythmias in which the mechanism involves early or delayed after depolarization-induced triggered activity. The authors share the view that I.V. magnesium is the drug of choice in "torsade de pointes" ventricular tachycardia accompanying acquired long QT/QTU syndrome. It is complementary therapeutic agent in digitalis-induced tachycardias. Further studies are needed to elucidate magnesium's mode of action and efficacy in other types of clinical tachyarrhythmias.

Animals↗
PubMed1993

Effects of magnesium and ethmozin on ventricular tachycardia induced by ouabain and ventricular pacing in conscious dogs with complete atrioventricular block.

A study was made of whether the administration of magnesium or ethmozin to conscious dogs with normal plasma Mg levels (0.75 +/- 0.06 mmol/l) terminates ouabain-induced ventricular tachycardia, an arrhythmia which is dependent on triggered activity resulting from delayed afterdepolarizations. Sustained monomorphic ventricular tachycardia was induced by programmed ventricular pacing during the continuous iv. infusion of ouabain to animals with a formaldehyde-induced permanent complete AV block. A single dose of MgSO4 (100 mg/kg b.w. iv.) abolished only those ventricular tachycardias with cycle lengths > 325 ms (inverse use-dependency); ventricular tachycardias with cycle lengths < 320 ms were merely slowed, despite the fact that the increase in plasma Mg levels was considerable and comparable in both groups (3.9 +/- 1.6 and 4.8 +/- 1.9 mmol/l). In contrast, ethmozin (2 mg/kg b.w. iv.) terminated both fast and slow ventricular tachycardias. It is concluded that ethmozin (moricizine) is more effective than the traditionally used MgSO4 in terminating ventricular tachycardia resulting from cardiac glycoside toxicity.

Animals↗
PubMed1993

The comparative antiarrhythmic and proarrhythmic activity of a 3,7-diheterobicyclo[3.3.1]nonane, BRB-I-28, and lidocaine in the 1-4-day-old infarcted dog heart.

We compared the electrophysiological effects and quantified the antiarrhythmic/proarrhythmic potential of the 3,7-diheterobicyclo[3.3.1]nonane-derivative, BRB-I-28 and lidocaine in 15 consecutive postinfarction dogs. Electrophysiologic studies were performed in anesthetized animals, 1-4 days (mean +/- SE = 2.47 +/- 0.36) after the two-stage ligation of the left anterior descending coronary artery. Inducibility of sustained monomorphic ventricular tachycardia (SMVT) was compared in the pre-drug state, and after i.v. lidocaine (3 and 6 mg/kg) and BRB-I-28 (3 and 6 mg/kg) administration. During the control state, SMVT was inducible in 6/15 dogs (40%). After the administration of lidocaine, the rate of the inducible SMVT slowed (353 +/- 91 to 272 +/- 96 beat/min; p < 0.01), but due to the proarrhythmic action of the drug, SMVT became inducible in 13/15 dogs (87%). Sustained reentry was induced after 3 mg/kg lidocaine in 3 dogs and after 6 mg/kg in 4. The mean aortic blood pressure in these SMVTs was 36 +/- 8 mm Hg. After administration of BRB-I-28 (6 mg/kg) SMVT was not inducible in 2/6 and in 4 the SMVT rate was slowed (380 +/- 104 to 208 +/- 105 beat/min; p < 0.005) before termination in 3. In 2 dogs SMVT was induced after BRB-I-28 was given whereas they were non-inducible in the control state (proarrhythmic effect: 13%). Furthermore the hemodynamic state during the SMVTs was more stable after BRB-I-28 (mean aortic blood pressure = 65 +/- 7 mm Hg; post-BRB-I-28 vs post-lidocaine, p < 0.001). During sinus rhythm, lidocaine caused a transient lowering of the MBP (105 +/- 17 to 84 +/- 18 mm Hg; p < 0.001), whereas, BRB-I-28, induced a consistent but short-lasting pressor response (98 +/- 18 to 120 +/- 29 mm Hg; p < 0.001) after its bolus injection. The low proarrhythmic activity and the lack of a cardiodepressant action makes this new chemical class of antiarrhythmics worthy of further development.

Animals↗
PubMed1992

Electrophysiological changes induced by lysophosphatidylcholine, an ischaemic phospholipid catabolite, in rabbit atrial and ventricular cardiac cells.

The effects of palmitoyl-lysophosphatidylcholine (LPC) were studied on the cellular electrical activity of rabbit heart preparations. LPC (100 mumol/l) caused a considerable enhancement of the automaticity of the SA nodal and Purkinje fibers and frequently induced irregular firing in both supraventricular (SA node, atrium, AV junction) and ventricular (Purkinje fibers, papillary muscle) myocardial regions. The 'automatotropic' and arrhythmogenic effects of LPC were accompanied by a lengthening of the atrioventricular conduction time. In ventricular muscle fibers LPC (100 mumol/l) decreased the resting potential (RP), the maximum rate of depolarization (Vmax) and the amplitude (APA) and duration (APD) of the action potential, and often evoked action potentials of 'slow response' type. In atrial muscle cells, 100 mumol/l LPC was capable of inducing hyperpolarization, with concomitant increases in RP, Vmax, APA and APD; higher concentrations (300 and 600 mumol/l) of LPC resulted in decreases in RP, Vmax, APA and APD, i.e. phenomena similar to those observed with 100 mumol/l LPC in the ventricular myocardium. The results seem to support the assumption that lysolipids accumulating in the ischaemic myocardium may play a pathogenetic role in the development of both supraventricular and ventricular dysrhythmias accompanying coronary artery occlusion.

Animals↗
PubMed1991

[Experience with the management of pyogenic liver abscesses by percutaneous transhepatic puncture and drainage].

The authors treated forty-two patients with liver abscesses guided by computer tomography or ultrasound percutaneous transhepatic puncture or drainage from January 1 1983, to 1989 December 31. Closed aspiration or drainage was done in 42 patients altogether 56 times. Three patients died (3/42 = 7.2%), postdrainage complications happened in 9 cases (9/42 = 21.4). Operative intervention was necessary in 11 patient after the percutaneous procedure (11/42 = 26.2%). The authors wrote about the technics particularly of the percutaneous puncture or drainage. The authors are considering the method as an effective treatment for pyogenic liver abscesses if the personal and technical circumstances are given.

Drainage↗
PubMed1991

[Primary malignant pericardial mesothelioma].

The case-history of a 41-year-old man is reported. He was admitted because of the sudden development of left hemiparesis, loss of consciousness and increasingly deeper coma. The ECG demonstrated second-degree AV block with Wenkebach conduction or episodes with complete AV block. The colour Doppler ultrasound and cranial CT examination revealed occlusion of the right internal carotid artery and a cerebral infarct of the right hemisphere. Within 24 hours patient died from herniation of the brainstem. Postmortem examination revealed a pericardial neoplasm infiltrating both left and right atrium, AV junctional area, interventricular septum and right ventricle. The tumor tissue grew transmurally and protruded into the cavities of the heart. The right internal carotid artery was occluded by a tumor embolism. The histochemical and immunohistochemical results proved that the tumor was a primary malignant pericardial mesothelioma. This kind of cardiac tumor involving the AV node and mimicking stroke is very rare.

Adult↗
PubMed1991

[Arrhythmogenic action of anti-arrhythmia agents. Current clinical view of pro-arrhythmias].

Recent knowledge relating to the proarrhythmic actions of antiarrhythmics is reviewed. After establishing the diagnostic criteria the authors discuss the incidence of proarrhythmias illustrating the wide spectrum of "drug-induced arrhythmogenesis" with clinical examples. The possibilities of recognition, prediction and prevention of proarrhythmic events and sudden death are outlined.

Anti-Arrhythmia Agents↗
PubMed1991

[Amidaron-induced dermatopathy resulting from unnecessary Cordarone therapy of ventricular parasystole].

The case history of a patient is reported who was treated with a variety of antiarrhythmics over a period of years because of refractory ventricular "bigeminy". As the arrhythmia did not respond to any kind of therapy, amiodarone treatment was started, which the patient received in a maintenance dose of 600-400 mg/day for 4 years. More recently, a bluish-grey hyperpigmentation of the face and other areas of the skin exposed to sunlight developed. A cutaneous biopsy of the hand revealed pigment deposits and lamellated lysosomal inclusions characteristic for amiodarone dermatopathy. The interactive, computer-assisted analysis of the ventricular ectopic activity has clearly demonstrated its innocent, parasystolic nature. The differentiation between ventricular extrasystolic and parasystolic activity is essential, because the latter arrhythmia does not require specific antiarrhythmic pharmacotherapy.

Amiodarone↗
PubMed1991

Hyperlipemia and hyperlipoproteinemia [HLP] screening among the children from premature myocardial infarction risk families.

Serum lipids and lipoproteins were investigated in the premature myocardial infarction (PMI) risk families before 45 years of age with the aid of screening for hyperlipemia and hyperlipoproteinemia (HLP): in the case of 174 persons from Csongrád County from the Departments of Internal Medicine I and II and of 42 patients (fathers) suffering from PMI and their 79 "high risk" children from Heves County. In the investigated three groups of "high risk" children the genetically determined antiatherogenic HDL-Ch level diminished in 34.8, 52.3, 40.5 per cent. Significant negative correlation was detected between the serum HDL-Ch and beta-lipoprotein; significant positive correlations were found between the HDL-Ch and the serum lipase activity; between the beta-lipoprotein and the phospholipid level; significant negative correlation was proved between the HDL-Ch and the phospholipid level in the group of PMI patients and their offsprings. The Ch/Tg, and the HDL-Ch ratios were significantly diminished in the PMI patients' group against the risk children' group, while the Ch/HDL-Ch rate was significantly elevated.

Adolescent↗
PubMed1991

A case of multiple cholangiogenic liver abscess due to residual biliary stone cured by percutaneous drainage controlled by CT and endoscopic papillotomy.

The case of a patient treated for multiple cholangiogenic liver abscess due to residual biliary stone after acute cholecystitis is reported. The multiple liver cyst was cured by percutaneous transhepatic double drainage controlled by CT as well as puncture and aimed local systemic antibiotic treatment. The residual gallbladder stone was removed by endoscopic papillotomy. A similar case has not been reported so far.

Ampulla of Vater↗
PubMed1991

Technique of extensive proximal selective vagotomy.

Based on the experience of 727 operations, the technique of proximal selective vagotomy used by the authors is reviewed in stages. They consider pyloroplasty justified to perform only in complicated cases (bleeding, perforation, stenosis) for preventing complications. Based on their results (mortality rate: 0.68%, recurrences: 6.3%, excellent or good results: 90%), they argue for the operation.

Chronic Disease↗
PubMed1991

Our experiences with the management of pyogenic liver abscesses by percutaneous transhepatic puncture and permanent drainage guided by computed tomography.

Thirty-three patients with pyogenic liver abscess were treated by percutaneous transhepatic puncture or permanent drainage between the period of 1, January 1985 and 31, December 1990. The closed puncture or drainage resulted in the complete recovery of 26 patients (26/33 = 78.8%). Surgical intervention was made 6 +/- 5 days following closed drainage in 7 cases (7/33 = 21.2%). After percutaneous intervention complications ensued in four patients (4/33 = 12.1%). One patient died (1/33 = 3%). Solitary abscess occurred in 24, while multiple in 9 patients. Based on the authors' experiences, they consider the closed percutaneous puncture, or drainage guided by computed tomography--provided that proper shills and facilities are available--them does not enable in all cases the precise preoperative diagnosis even despite its richness of detail. In order to reduce uncertainties and to establish an accurate diagnosis, Herbert et al., McCorrcel et al. and Perera et al. proposed three criteria to be met before establishing the diagnosis of pyogenic liver abscess. According to the authors the conditions for accepting these criteria can be summarized as follows: 1. On the US examination of the liver, echo-free or echo-poor regions can be seen with increased background echoes. CT verifies an inhomogeneous, circumscribed or irregular-shaped, blurred focus of finely deformed contours being hypodense in contrast with the environment. On administration of contrast medium, the change is surrounded by a hyperdense border, and other causes for the above change can be excluded. 2. Verification of the presence of pus (by percutaneous puncture or surgery) from the liver biopsy. 3. The negative result of serological tests characteristic of amoebic infection. CT and US examinations have opened up new vistas not only in establishing diagnosis but also in the management of the disease. The closed percutaneous and effective method in the management of liver abscesses.

Adolescent↗