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At least 289 records · Page 16Linked to original sources
PubMed1972

Retrograde conduction from artificial pacemaker to atria in sick sinus syndrome.

The influence of retrograde conduction of the artificial pacemaker impulse from the right ventricle to the atria exerted upon the occurrence of rapid supraventricular rythms was investigated in patients with sick sinus syndrome. The bouts of tachycardia occurred in cases with fixed V-A retrograde block or coincided with temporary V-A block. The usually operating retrograde conduction from the pacemaker to the atria protects the patients from paroxysms of supraventricular tachycardia by means of the coordinated depolarization of the atria and junctional tissue.

Arrhythmia, Sinus↗
PubMed1976

Prognosis of patients with complete heart block or arrhythmic syncope who were not treated with artificial pacemakers. A long-term follow-up study of 101 patients.

This paper reports the results of a retrospective study carried out with special reference to the survival rate in a series of 101 selected cases including patients with complete heart block (CHB) combined or not combined with Adams-Stokes attacks and patients with arrhythmic syncope without ECG evidence of CHB. All these patients were treated in our Department during 1958-68, none being artificially paced. Twenty-seven patients were alive at the end of the follow-up, i,e 6-15 years after admission to this Department on account of syncopal episodes or CHB. The survival rate--higher in females than males--was lower in the cases of CHB combined with Adams-Stokes attacks than in the cases of asymptomatic CHB. This applied also to the instances in which a complicating disease such as ischaemic heart disease (IHD), hypertension, diabetes, digitalis intoxication or cardiac enlargement coexisted. The survival rate in the 68 cases of CHB was higher at one year (68%) as well as at 5 years (37%) than that reported by other investigators. When assessing the survival rate in cases treated with artificial pacemakers, it is important to study the individual case histories with special reference to a previous or coexisting condition such as IHD, hypertension, diabetes or the presence of cardiac enlargement. The present results support the view that the indications for treatment with artificial pacing should be wide, albeit that the prognosis in this series was more favourable than might have been anticipated from observations by others.

Adams-Stokes Syndrome↗
PubMedDate not supplied

[The cardiohemodynamic characteristics of the action of obzidan in patients with an artificial pacemaker and ischemic heart disease with different types of blood circulation].

The effect of a single administration and a 2-week course of obsidan treatment on cardiohemodynamics was studied in patients with an artificial cardiac pacemaker and a fixed rate of electrocardiostimulation. Echocardiography showed that obsidan reduced heart contractility and pump function in patients with an artificial cardiac pacemaker and different types of blood circulation (hyper-, eu-, and hypokinetic). The cardiohemodynamic effects of obsidan were found to be dependent on the initial type of circulation and the features of intracardiac hemodynamics in different modes of cardiac pacing.

Adult↗
PubMed1984

Different response of left ventricular dimensions to nitroglycerin in patients with artificial pacemaker. A possible significance of reflex tachycardia for the reduction of LV cavity after nitroglycerin.

The effects of nitroglycerin (NTG) on cardiac function can be evaluated by echocardiography. In this paper, we discuss the effects of NTG on cardiac function in two groups of subjects, one with artificial pacemakers implanted with a fixed heart rate, and the other examined as the control group. Left ventricular dimension was obtained in the standard manner using the electronic sector scanning system of Toshiba SSH-11A. Left ventricular end-diastolic and end-systolic dimensions (Dd and Ds) were obtained in each case and the ejection fraction was calculated. After the sublingual administration of NTG (0.6 mg), the blood pressure decreased in both groups. The ventricular rate was fixed in the pacemaker group but increased significantly in the control group. Dd and Ds were found to decrease only in the control group. The ejection fraction showed an increase in the majority of the control group but remained unchanged in the pacemaker group. Heart rate change therefore may play a role in dimensional change and pumping function of heart after NTG.

Adolescent↗
PubMed1990

[Various diagnostic criteria for abnormal signs of the artificial pacemaker examined by transesophageal electric stimulation of the left atrium].

Forty eight patients with abnormal sinus node were subjected to transesophageal electric stimulation (TES) of the left atrium to assess the length of poststimulation pauses (PSP) and the first 5 spontaneous sinus cycles after TES cessation. Higher values of PSP were found in patients with the sick sinus syndrome than in healthy subjects. Transition of TES to sinus rhythm is of practical value. In patients with the sick sinus syndrome, the first sinus contraction was shorter by 4.6% than the last PSP after TES (the respective value being 16.6% in healthy subjects), whereas this parameter was 20.9% (p less than 0.01) in patients with autonomic dysfunction of the sinus node. Hence, the functional potentialities of sinus node activity recovery are inconclusive with its various abnormalities, which may serve as one of differential diagnostic criteria for organic or functional pathology of a cardiac pacemaker.

Adult↗
PubMed1977

[Artificial pacemakers].

The new generation of pacemakers satisfy three basic requirements; histocompatibility, small size, and long life. Resins have been abandoned in favour of titanium cases. These are completely sealed and there is no risk of infiltration or histotoxicity. In addition, the employment of low consumption circuits and new sources of energy, especially lithium, has enabled the working life of a pacemaker to be extended virtually to its useful limits. The application of electrical stimulation to the treatment of arrhythmia has led to the creation of automatic or magnetically controlled pacemakers that come into action with pulse volleys on the appearance of otherwise intractable rhythm disturbances.

Arrhythmias, Cardiac↗
PubMed1998

[The medical rehabilitation of patients with an artificial pacemaker].

AIM: To study prognostic significance of individual rehabilitation of patients with pace-maker with account for leading cardiac syndromes. MATERIALS AND METHODS: 375 patients with artificial pace-maker were treated in a cardiological hospital for cardiac failure, blood hypertension, angina pectoris, cardiac arrhythmias. RESULTS: Congestive heart failure, blood hypertension, secondary cardiac arrhythmia, angina of effort were diagnosed in 57.4, 44.4, 33.0. 30.6% of the studied patients with artificial pace-maker. The patients died primarily of cardiac diseases, cancer and complications of cardiac pacing (71.3, 14.9 and 6.7% of cases, respectively). CONCLUSION: Aftercare of patients with pace-maker should be performed in groups of follow-up (5 groups) according to specially designed programs of diagnostic, therapeutic and prophylactic measures.

Adolescent↗
PubMed1977

Exit block of artificial pacemaker induced by carotid sinus massage.

Failure of the pacemaker is a common complication of pacemaker therapy. Identification of the disorder responsible for the failure to pace is often difficult. An increase in myocardial threshold can result in nonconduction of the artificial impulse, particularly near the end of the life of the battery, when the output of current has started to decline. This report demonstrates such an increase in myocardial resistance which was apparent only upon massage of the carotid sinus.

Aged↗
PubMed2001

[Is brain blood supply affected by changes in cardiac volume? Measurements of brain blood supply in healthy subjects during volume overload and in patients with artificial pacemaker by changing the pacing rate].

A constant cerebral blood flow (CBF) in the presence of systemic blood pressure changes and cardiac output (CO) alterations during physiological conditions are postulated by the mechanism of cerebral autoregulation. The aim of the present study is the analysis of CBF in pacemaker (PM) patients with unspecific neurological symptoms. CBF was measured in 9 controls and 23 pacemaker patients with 133xenon, CO using Doppler echocardiography or impedance cardiography. Mean and individual CBF in controls remained unchanged when a CO increase of 28% induced by volume overload was observed. In PM patients a mean CO increase of 38% induced by an increase of basic pacing rate caused different effects of CBF. CBF increased or decreased by about 10% or remained constant. In summary, the data suggest an impairment of cerebrovascular function in those patients with concomittant CBF changes due to CO alterations (15/23 approximately equal to 65%). Thus, the analysis of brain perfusion in PM patients with unspecific neurological symptoms is possibly a new diagnostic feature in the future. It can be discussed whether or not indication and optimizing of pacemaker therapy has to be additionally analyzed by determination of endorgan perfusion.

Adult↗
PubMed1978

The influence of atrial systole on ventricular capture by failing artificial pacemakers. II. Experimental observations.

The mechanism by which atrial systeole influences the efficacy of ventricular capture by a failing pacemaker was investigated in 12 dogs with atrioventricular heart block. Atrial systole caused facilitation of ventricular capture in eight dogs, and inhibition of capture in 10 dogs. Interpolating atrial extrasystoles caused an enhancement or depression of the hemodynamic performance of the atrial systole that affected the efficacy of the pacemaker stimulus. These interpolation experiments showed that atrial systole influenced the efficacy of capture by a mechanical mechanism and not by an electrotonic mechanism. Atrial systole probably caused motion of the endocardial pacing catheter and/or ventricular myocardium. This motion increased or decreased the contact between the pacing electrode and the endocardium with subsequent changes in the efficacy of capture. In three dogs with pacing through epicardial electrodes, atrial systole had no effect on the efficacy of capture.

Animals↗
PubMed2001

[Indications and results of artificial pacemaker implantation in children].

Since 1989 till 1999 operations were performed on 74 children aged from 13 months to 15 years. There were 130 operations, 56 reoperations included. Iatrogenic atrioventricular blockades were diagnosed in 47 children (63.5%), congenital and postmyocarditic alterations in the rhythm and cardiac conductivity--in 27 children (36.5%). In 48 patients the primary implantation of electrocardiostimulators was fulfilled using myocardial electrodes, in 26 cases the endocardial method was used. Three children died at the postoperative period. The causes of death were the growing heart failure, hypoxic brain edema, ventricular fibrilation. ECG, Holter monitoring, echocardiography with dopplerography were made in the children in order to solve the question of the implantation of artificial pace-makers. At the postoperative period the electrocardiostimulators' parameters were selected individually under control of echocardiography.

Adolescent↗
PubMed1980

[The vectorcardiogram of patients with artificial pacemakers].

Frank's technique has been used to study the behaviour of the vectorial loop in 20 subjects wearing fixed frequency pacemakers. A broad study has been carried out non characteristics and modalities of transmission of the artificial stimulus. The morphological features of the vectorcardiogram differ in accordance with the location of the stimulated point. Special attention is paid to the possibility of the catheter-electrode penetrating the coronary sinus during right intracavitary pacing and the consequent vectorial and radiological characteristics such an eventuality involves. Some remarks are offered on the orientation of the extrastimulus, depending on its point of origin. It is concluded that knowledge of the course of the vectorial curve may be extremely useful for establishing the site of the extrastimulus in pacemaker wearers.

Bundle-Branch Block↗