Biomedical subjects

F Solti

Publications and source records attributed to F Solti.

At least 19 recordsLinked to original sources

PubMed1992

[Regulation of blood circulation in the extremities in intermittent claudication].

UNLABELLED: The study was aimed to investigate the characteristics of the limb circulation in patients suffering from intermittent claudication. The study group consisted of 71 patients with intermittent claudication. As control served the data of 60 patients with intact peripheral circulation and 24 patients suffering from rest pain, too. The limb blood flow was measured by the venous isotope dye-dilution method. RESULTS: 1. The limb blood flow will be diminished in intermittent claudication already in resting state. The decrease of the limb blood flow is more expressed in severe claudication (with short claudication distance). 2. The pathological condition of the limb circulation in intermittent claudication can be characterized by the elevation of the limb vascular resistance. 3. The O2 consumption of the limb tissues will decrease in intermittent claudication. The data of the study are indicating that the regulation of the limb circulation will pathologically be changed in claudication. The reserves of the peripheral circulation are diminished and the insufficiency of the limb circulation will be manifested on walking.

Adult↗

PubMed1992

Congenital complete heart block associated with QT prolongation.

The coexistence of congenital complete heart block and QT prolongation represents a special type of arrhythmia. The electrophysiological and clinical characteristics of this syndrome were studied in eight patients suffering from congenital AV block and QT prolongation. Data from 22 patients suffering from congenital complete heart block only, served as a control. In the study group, the appearance of a torsade de pointes type of ventricular tachycardia could regularly be observed and the tachycardial attack could usually be provoked by ventricular extrastimuli. The corrected QT time was markedly prolonged; on ventricular stimulation, at higher pacing rates the QT interval shortened, but remained significantly higher than in the control group. Syncopal attacks--with the character of polymorphic tachycardia--appeared in each patient of the study group while occurring in only three patients from the control group. Patients were given pacemaker implants (using a higher pacing rate) and long-term administration of beta-receptor blockers. The outcome was favourable; no ventricular tachycardia or syncopal attack was observed in the follow-up period.

Adolescent↗

PubMed1991

Lymphatic arteriopathy: damage to the wall of the canine femoral artery after lymphatic blockade.

The effect of lymph stasis on the histological, biochemical, and elastic properties of the femoral artery were studied after regional lymphatic blockade in 36 dogs. Dogs were sacrificed 4-21 days after operation. Histologic changes of the femoral arterial wall (interstitial edema, degeneration in the muscle layer or media, thickened adventitia with dilated lymph vessels, and fibrosis) developed after regional lymphatic blockade. Characteristic metabolic alterations of the arterial wall (anaerobic catabolism of carbohydrate, increased lactate and glycosamine content) accompanied the morphological changes. Distensibility of the femoral artery decreased and greater elastic stiffness developed after regional lymphatic blockade. These results in conjunction with other experimental and clinical data support the concept that insufficient lymphatic transport within the blood vessel wall may contribute to the genesis and progression of arteriopathies.

Animals↗

PubMed1990

Atrial standstill: an indication for rate responsive pacing.

Atrial standstill (atrial paralysis) is a rare reason for permanent bradycardia. A case of atrial standstill is presented. A 35-year-old man had suffered from bradycardia since his childhood. For 2 years he had complaints (diminishment of his working capacity, and dyspnea occurred with effort) as well. On admission, a slow (38/min) junctional escape rhythm could be detected. There were no signs of atrial mechanical activity (atrial contraction) according to chest x ray, echocardiography, and the atrial pressure curve. The electrophysiological study revealed that the atria could not be electrically stimulated, and no P wave (A wave) could be recorded on right atrial electrograms. The patient received a rate responsive pacemaker. After pacemaker implantation, he became symptom-free; his working capacity improved markedly and his heart size decreased. Owing to the permanent bradycardia and the lack of atrial stimulation, the atrial standstill represents an indication for ventricular rate responsive pacing. Atrial standstill, permanent bradycardia, and the inability to stimulate the atrium are indications for ventricular rate responsive pacing.

Adult↗

PubMed1990

Characteristics of the limb circulation in hypertension.

The aim of this study was to investigate the effect of hypertension on the regulation of limb circulation. The study group consisted of 50 patients suffering from hypertension; in 21 cases the peripheral circulation was intact, while 29 patients had peripheral obliterative arterial disease (POAD) (clinical symptoms: intermittent claudication or rest pain). The control group consisted of 67 normotensive patients. In 33 subjects of the control group the peripheral circulation was intact, while 34 patients suffered from POAD (clinical symptoms: intermittent claudication or rest pain). The total limb blood flow (LBF) was measured by using venous isotope dilution technique. In hypertensive patients the limb vascular resistance (LVR) was markedly elevated, but the LBF remained in the normal range. In patients suffering from both hypertension and POAD the LVR was pathologically elevated and the LBF markedly diminished. After acute vasodilator therapy the LBF significantly increased, despite the drop in blood pressure owing to the extensive decrease of the LVR. It appears that in hypertension the elevation of the LVR is the most characteristic change of the limb circulation. The elevation of the arterial blood pressure has no favorable effect on the limb circulation, and the LBF compared with the blood pressure is relatively low.

Adolescent↗

PubMed1990

The effect of vasodilator therapy on the limb circulation in hypertension.

The effect of vasodilator drugs on limb circulation was investigated in 59 hypertensive patients. Forty-six of them suffered from obliterative arterial disease, too. The drugs administered were: hydralazine, nitroglycerine and sodium nitroprusside. Isotope dilution method was employed to assess limb blood flow before and after acute treatment. Limb vascular resistance was calculated from the limb blood flow and the mean blood pressure. A marked increase in limb blood flow and decrease in vascular resistance following vasodilator treatment were observed in hypertensive patients suffering from obliterative arterial disease. No difference was found between the various vasodilators investigated. Normotensive patients with arterial disease exhibited the same response to a lesser degree. In exceptional cases, where blood pressure dropped abruptly, limb blood flow decreased and limb vascular resistance increased. The data show that vasodilator therapy in hypertension results in diminished limb vascular resistance and improved limb circulation in patients with obliterative arterial disease.

Arterial Occlusive Diseases↗

PubMed1990

[Changes in the femoral vein in dogs as an effect of experimental lymphedema].

Authors studied changes of femoral vein developed by the effect of examinations experimental lymphoedema in dogs. Light and electronmicroscopic were performed from femoral vein of animals killed on 3rd and 14th postoperative day, and biomechanical examinations were done too from dogs killed on 14th postoperative day. In vessel wall edema, fibrosis, and in valves infiltration consisting of macrophages, neutrophilic granulocytes and of mesenchymal cells were observed. Biomechanical examinations did not show significant deviation. Their results suggest the possibility that extremital lymphoedema also in man may contribute to development of varicosity or to its aggravation. Experimental lymphoedema of lower limb of dog can be proposed as model experiment to the complex study of pathogenesis of development of varix.

Animals↗

PubMed1990

Regulation of circulation in congestive heart failure.

Regulation of extremity (limb) circulation was studied in 21 patients suffering from congestive heart failure. In 11 cases the peripheral circulation was intact, while 10 patients also suffered from peripheral obliterative arterial disease. Data of 75 patients with normal cardiac condition served as control: 35 subjects with intact peripheral circulation and 40 patients suffering from peripheral obliterative arterial disease. Limb blood flow was measured by using venous isotope dilution technique. Cardiac output was determined by the dye dilution method. In chronic heart failure the limb circulation characteristically deviated from the normal; the limb blood flow and the limb oxygen consumption slightly decreased, while the limb vascular resistance markedly increased. The diminution of the limb blood flow and the increase in the limb vascular resistance due to obliterative arterial disease were more pronounced in patients suffering from congestive heart failure. The pathological increase in the peripheral vascular resistance due to chronic heart failure proved mostly reversible; on the administration of vasodilator drugs the elevated limb vascular resistance markedly decreased and the limb blood flow significantly increased.

Adult↗

PubMed1989

[New aspects of the Kearns-Sayre syndrome].

The case report of the 23 years old female with Kearn-Sayre syndrome started about 15 years ago has some special cardiological aspects. By His band ECG the height of III. degree atrioventricular block was located in the atrioventricular node which is in sharp contrast with all former findings localizing the block into or distal to His band. In the pathogenesis of the unexpected block localisation--besides the muscular degeneration accepted generally in KSS--the recent myocardial infarction of the patient could have a causal role. Electronmicroscopical investigation carried out on the biopsy specimen from the right ventricle revealed both the characteristic hallmarks of "generalized mitochondriopathy" and the pathological glycogen accumulation having been published in skeletal muscles before. The mitral valve prolaps diagnosed in the patient has never been mentioned in KSS. Trauma suffered in early childhood might have a pathogenetic role. In discordance with literature steroid treatment of the diabetic patient with KSS didn't result in lactacidosis.

Adult↗

PubMed1989

[Malignant arrhythmia].

About 5 percent of the arrhythmias are serious, life threatening, malignant arrhythmias (MA). The MA is regularly associated with organic heart diseases (coronary heart disease, cardiomyopathy, valvular heart diseases), but a MA can develop without cardiac disorders e.g. in long QT syndrome or WPW syndrome. The most frequent type of the MA is the ventricular tachycardia (VT), mostly the sustained VT, not rarely degenerating to ventricular fibrillation (VF). The primary VF represents a rarer form of MA. The usual type of MA is the tachycardiac form, but there exists a MA with dominating bradycardia (bradycardia syncope, tachycardia associated with long lasting bradycardia). In the diagnosis of MA new investigatory methods (signal averaged electrography with high amplification, Holter monitoring, programmed electrical stimulation) play an important role. In the therapy of the MA the first step is the treatment of the cardiac disease involved in the pathogenesis of the MA. At present only about the 40% of the MA can be effectively treated with antiarrhythmic drugs. The pacemaker therapy is very efficacious in the bradycardiac type of MA. Cardiodefibrillator pacemaker can be used for the treatment of grave VT or VF. Electrical transvenous catheter ablation, heart surgical intervention can also be applied in the treatment of special MA. The prognosis of VA was very serious a decade ago, now with application of newer therapeutical procedure the prognosis of MA is permanently improving.

Arrhythmias, Cardiac↗

PubMed1989

Effect of two week lymphatic occlusion on the mechanical properties of dog femoral arteries.

In order to study the long-term effect of impaired lymphatic drainage on the mechanical properties of the arterial wall, cylindrical femoral artery segments from 10 mongrel dogs after 2 weeks of hindlimb lymphatic occlusion were subjected to in vitro mechanical test and compared with the contralateral, sham-operated segments. Smooth muscle contraction was induced by norepinephrine (7.4 X 10(-6) M) and smooth muscle relaxation by papaverine (1.6 X 10(-4) M). As a result of 2 weeks of lymphatic occlusion, wall thickness increased from 243 +/- 18 to 343 +/- 35 microns (P less than 0.02), inner radius decreased from 1.69 +/- 0.11 to 1.42 +/- 0.12 mm (P less than 0.01) and elastic modulus decreased from 1.23 X 10(6) to 0.55 X 10(6) N/m2 (P less than 0.01), when determined at 100 mm Hg (13.3 kPa) intraluminal pressure and with relaxed smooth muscle. The contractile apparatus was able to produce active strain in the vessels with lymphostasis and at physiological pressures not significantly different from the controls (0.89 +/- 0.02 vs. 0.91 +/- 0.02), but at significantly lower levels of tangential stress. Active stress decreased significantly. This study shows that a reorganization of the vessel wall mechanical force-bearing elements occurs in lymphostasis, which, in some respects, resembles the mechanical alterations found in different forms of atherosclerosis.

Animals↗

PubMed1989

The effect of atrial dilatation on the genesis of atrial arrhythmias.

The effect of atrial stretching on the genesis of atrial arrhythmias was studied in 26 dogs. Left atrial dilatation was produced by inflation of a balloon catheter. Electrophysiological studies were performed by programmed electrical stimulation of the atrium and ventricle. The irritability of the atrium markedly increased when it was distended and atrial arrhythmias (sustained or non-sustained atrial tachyarrhythmias) could regularly be induced by administration of an early extrastimulus or--more rarely--by atrial burst pacing. In 10 cases spontaneous atrial tachycardia appeared during atrial balloon dilatation. The atrial effective refractory period shortened and the atrial conduction time lengthened on atrial stretching, while other electrical variables (cycle length, sinus node recovery time, atrioventricular conduction time, intraventricular conduction, ventricular refractory period, QT interval) remained unchanged. Atrial balloon dilatation was not accompanied by marked haemodynamic changes, and the left ventricular pressure curve, the contractility of the left ventricle and the central venous pressure did not change significantly on atrial stretching. The experimental data suggest that the atrial dilatation plays an important part in the pathogenesis of atrial arrhythmias.

Animals↗

PubMed1989

Pacemaker twiddler's syndrome (rotation of the pacemaker around the electrode cable, a rare complication of pacemaker therapy).

Rotation of the pacemaker generator around the electrode cable (i.e. twiddler's syndrome) was observed by the authors in six cases during the implantation of 4250 pacemakers. Twiddler's syndrome developed in three cases following implantation and in three cases after the replacement of the pacemaker. As a result of the rotation of the device, displacement of the electrode occurred in all cases. The factors predisposing to rotation of the device were as follows: (i) a loose, dilated pocket in 5 cases; (ii) seroma formation around the device in 2 cases; (iii) manipulation with the pacemaker in one case. For treating twiddler's syndrome, reimplantation was performed, fashioning a small and tight pocket for the device and fixing it by transfixing sutures. After reimplantation, the patients became complaint free, no recurrences occurred.

Aged↗

PubMed1989

Effect of atrial dilatation on the tendency of atrial arrhythmias.

The arrhythmogenic effect of atrial dilatation was studied by electrophysiological investigations carried out on 24 dogs. Atrial distension was evoked by increasing the pressure in the right atrium (12 to 14 mm Hg) or by the balloon dilatation of the left atrium. Programmed electrical stimulation of the heart was used for the electrophysiological investigations. In addition to the superficial ECG leads also atrial and ventricular epicardial electrograms were obtained for the ECG recording. Acute atrial dilatation led to shortening of the atrial refractory period, whereas neither impulse conduction of the heart, nor pacemaker activity of the sinus node exhibited any alteration. Atrial dilatation resulted in pathological atrial irritability, and early or frequent atrial stimulation caused atrial tachycardia of shorter (non sustained) or longer (sustained) duration. Repetitive atrial extrasystoles in response to early stimuli could also frequently be observed during atrial dilatation. The obtained results indicate that atrial dilatation is arrhythmogenic and may lead to the development of atrial tachycardia.

Animals↗

PubMed1989

The effect of sympathetic and parasympathetic activity on QT duration. Clinical study in patients with normal and prolonged QT time.

The effect of parasympathetic and sympathetic pharmacologic blockade (atropine and propranolol) on QT duration was studied in 26 patients. Of this number 17 had a normal QT time, while in 9 patients the QT interval was prolonged (greater than 460 ms). QT time was determined before and after the pharmacologic blockade with sinus rhythm (under a non fixed cycle length) and with atrial pacing (with a fixed cycle length). Atropine administration did not change QT duration significantly. On the effect of beta receptor blockade in normal patients only the corrected QT time shortened, while in long QT syndrome a very pronounced shortening in QT time, independent of the changes in the cycle length, could be observed. In QT prolongation an overactivity in the sympathetic tone can be supposed.

Adult↗

PubMed1989

Intrinsic and extrinsic sinus node dysfunction: diagnostic problems.

Based on clinical and experimental experience, pacemaker dysfunction in sick sinus syndrome can be differentiated into intrinsic and extrinsic. Sinus node activity is characterized electrophysiologically by automaticity, recovery and sinoatrial conduction. The automaticity of the sinus pacemaker cell groups and sinus recovery can be differentiated properly under experimental conditions. Studies of the electrophysiological characteristics have shown the basic functional parameters to be normal in extrinsic-autonomic sinus dysfunction. Diagnosis is either based on clinical observation or on the data of Holter monitoring, the electrophysiological methods being inadequate for diagnosing this neurovegetative form of sick sinus syndrome. On the other hand, intrinsic sinus dysfunction can be diagnosed by electrophysiological tests. If completed by complex pharmacological studies, in this organic form of sick sinus syndrome, even the severity of the intrinsic injuries can be assessed quantitatively. The above division provides a basis for selection and evaluation of the differential diagnostic procedures, while information on the aetiopathology of sinus dysfunction and on the degree of the functional injuries of the electrophysiological structure of the heart provides an adequate basis for therapy.

Adult↗

PubMed1989

The characteristics of the peripheral-limb-circulation in congestive heart failure.

The regulation of the peripheral-limb circulation was investigated in 21 patients suffering from chronic cardiac failure (NYHA stage II and III). In 11 patients the extremital circulation was intact, while 10 patients suffered from peripheral obliterative arterial disease, too (intermittent claudication or rest pain). The control group consisted of 75 subjects with normal cardiac condition. In 35 of the control subjects the peripheral circulation was intact, the remaining 40 suffered from extremital venous isotope dilution technique. In congestive heart failure the limb blood flow and the limb oxygen consumption slightly diminished, but remained in the normal range. The limb vascular resistance significantly increased. In patients suffering from intermittent claudication or rest pain, the marked diminution of the limb blood flow and elevation of the vascular resistance was more pronounced in congestive heart failure than in healthy subjects. The pathologically elevated limb vascular resistance decreased and the limb blood flow significantly increased in congestive heart failure on administration of vasodilator drugs. A pathological and mostly reversible increase in extremital vascular resistance is the most characteristic sign of the peripheral circulation in congestive heart failure.

Adult↗

PubMed1988

Decreased vascular contraction and elastic stiffening after intramural lymphostasis.

Lymphatic obstruction leads to leakage of protein into the vessel wall that is coupled with edema formation and smooth muscle degeneration. To clarify the mechanical effect of these changes, lymphatic trunks, draining the femoral artery, were stained with Evans blue and then ligated in dogs anesthetized with pentobarbital sodium (n = 11). Sham ligation was performed on these lymphatic trunks in the opposite hindlimb (n = 11). Three days later, 7- to 30-mm segments of both femoral arteries were studied in vitro. Intraluminal pressure was cycled between 5 and 250 mmHg at 5 mmHg/s, and external diameter was recorded in both relaxed and activated (norepinephrine, 3 x 10(-5) mol/l) state of smooth muscle. Mechanical parameters were computed for 10-mmHg pressure increments. After lymphatic obstruction, strain energy density and distensibility of the passive wall components as well as isobaric active tangential strain were decreased by a maximum of 27, 59, and 54%, respectively; active tangential stress and elastic modulus, as a function of tangential stretch, was decreased by a maximum of 62%, and increased by 61%, respectively. These results indicate that short-term intramural lymphostasis reduces smooth muscle reactivity and induces vascular stiffening.

Animals↗