Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0018801 (heart failure)
 72,216 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In patients with sinus node disease (SND) the VVI pacing seems an inappropriate mode of cardiac stimulation because of its potential hemodynamic and arrhythmic adverse effects. The AAI-DDD pacing, preferred because of a lower morbidity, might also determine higher survival. We examined retrospectively 2 groups of patients with SND respectively stimulated with VVI pacing (Group I:57 patients) and AAI (Group II:53 patients). The mean follow-up was 43 months for Group I and 50 for Group II: 10 (17.5%) patients in VVI group and 5 (9.4%) in AAI group died. During the follow-up in the VVI group 3 patients developed congestive heart failure and 10 chronic atrial fibrillation whereas 1 case of heart failure and 2 of atrial fibrillation have been recorded in AAI group. Moreover, 4 patients had embolic complications in Group I; 5 (9.4%) patients with VVI pacing were converted into sequential pacing owing to occurrence of II degree heart block. The statistical analysis was performed by chi 2 test for the comparison among the proportions of events (atrial fibrillation, congestive heart failure, embolic accidents) in the 2 groups: a significative higher morbidity (p less than 0.01) was recorded in VVI group. Survival also is higher in AAI patients but the survival rate difference, calculated with Mantel-Cox method, is not statistically significant. The findings of this study show that in SND the superiority of AAI pacing over VVI is statistically significant as regards morbidity and we have also noticed an evident but not statistically significant superiority as regards mortality.
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PMID:[Comparative effects of atrial and ventricular stimulation on morbidity and mortality in patients with sinus node disease]. 207 40

In this work we intend to analyze the long term effects of the classic modes of definitive cardiac pacing (VVI and DDD) on the atrial natriuretic peptide levels. A priori hypothesis is: the AV asynchrony raises the hormonal level. The design is a cross-sectional study, and the setting is the pacemaker doctor's room of a tertiary hospital. In 24 patients (17 VVI and 7 DDD) the atrial natriuretic peptide was determined by RIA. A multiple regression model was fitted to analysis. The basic result is: when several factors were controlled (age, sex, hypertension, and cardiac failure story), the atrial natriuretic peptide levels are increased in the VVI group. In conclusion, the lack of AV synchrony induced the increase of atrial natriuretic levels. For an endocrine viewpoint the DDD is more physiological pacing as well.
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PMID:[Long-term effects of cardiac pacing on natriuretic atrial peptide levels in patients with AV block]. 214 21

The beneficial effects of physiologic dual-chamber (DDD) pacing in the treatment of end-stage idiopathic dilated cardiomyopathy were evaluated in 16 patients in whom conventional drug therapy had failed. Candidates for cardiac transplantation as well as patients not accepted for transplantation participated. During DDD pacing at an atrioventricular delay of 100 ms, left ventricular ejection fraction increased from 16.0 +/- 8.4 to 25.6 +/- 8.6% (p less than 0.001) accompanied by a striking improvement in clinical symptoms, such as severe dyspnea at rest and pulmonary edema. The New York Heart Association class decreased from 3.6 +/- 0.4 to 2.1 +/- 0.5 (p less than 0.001). The decrease in cardiothoracic ratio from 0.60 +/- 0.06 to 0.56 +/- 0.05 (p less than 0.001) coincided with a decrease in left atrial and right ventricular echocardiographic dimensions, indicating a decrease in preload. Systolic blood pressure increased from 108 +/- 29 to 126 +/- 21 mm Hg (p less than 0.01) and diastolic blood pressure from 67 +/- 15 to 80 +/- 11 mm Hg (p less than 0.01). Normalization of heart rate was achieved. No major complications developed as a consequence of DDD pacing. All patients could be discharged from the hospital within 3 weeks after pacemaker implantation and return to a relatively normal life. Within 1 year after onset of DDD pacing only 4 of the patients died (from either sudden death or stroke). DDD pacing could represent an alternative approach to the management of chronic heart failure due to dilated cardiomyopathy, especially for heart transplant candidates and patients who are not accepted for cardiac transplantation, but no longer respond to drug therapy.
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PMID:Usefulness of physiologic dual-chamber pacing in drug-resistant idiopathic dilated cardiomyopathy. 237 55

The aim of this prospective study is comparing long-term prognosis in patients implanted with a VVI pacemaker (group A) with those implanted with a sequential pacing device, AAI or DDD, (group B). Both groups of 45 patients each, were comparable as regards to age, sex, pacing indications, underlying heart disease, and technical conditions of implantation and were followed-up over 55 months. Atrial arrhythmias (A.A.) incidence was higher in group A: 24.4% than group B: 8.8% (P less than 0.05). Arterial embolisms (A.E.) occurred in group A patients only. Worsening or occurrence of exercise limitation was more frequent in group A: 35.6% as compared to group B: 13.3% (P less than 0.05) and deaths related to these complications, occurred in seven cases in group A versus four cases in group B. In group A, all patients who experienced a worsening or occurrence of an A.A. or an A.E., had a ventriculoatrial conduction (VAC). No statistical difference was observed in worsening or occurrence of exercise limitation between patients with VAC and those without VAC: nine (42.8%) and seven (29.2%) but they respectively experienced at least one complication in 16 cases (76.2%) and seven cases (29.2%) (P less than 0.01). In conclusion, long-term prognosis in patients implanted with VVI pacing as compared to patients implanted with sequential pacing is poorer. The presence of VAC in patients treated with permanent VVI pacing is a major factor for complications and deaths related to A.E. and cardiac failure. Thus VVI pacing should be avoided in patients with VAC.
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PMID:Long-term follow-up of patients treated with VVI pacing and sequential pacing with special reference to VA retrograde conduction. 246 68

This is a retrospective study of 16 children with congenital complete atrioventricular block (CAVB) who were fitted with a pacemaker in infancy. All were neonates admitted at the age of 1 to 9 days for bradycardia; 3 had a cardiopathy. In 8 children a permanent pacemaker was implanted in the first two days of life on account of a heart rate slower than 50 beats/min, accompanied with threatening symptoms (heart failure or syncopes) in 4 cases. In 6 children the pacemaker was implanted at the age of 2 to 3 months; in spite of reassuring electrocardiograms, 5 of them were readmitted in an emergency for heart failure or syncope with slow heart rate; the 6th patient had disorders of ventricular excitability. Finally, 2 asymptomatic infants underwent pacing: one at 20 days for bundle branch block, the other at 6 months for slow phase abnormalities. Pacing was epicardial in all patients, the chamber being positioned in the space that separates the kidney from the parietal peritoneum. Ventricular synchronous pacing (VVI) was applied in 14 cases and atrioventricular pacing (DDD) in the two most recent cases. Two children died post-operatively, due to inadequate attachment of the electrode resulting in loss of ventricular capture in one case, and to extensive left atrial thrombosis in the other case. Two children died at a later stage of severe respiratory pathology. The 12 survivors were followed up for a mean period of 3.7 +/- 3.1 years. Three pacemakers were replaced: one at 28 months for infection, the others at 3 and 6 years respectively for running down of the batteries.2 +
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PMID:[Artificial cardiac stimulation in the newborn infant with complete congenital atrioventricular block. Study of 16 cases]. 250 99

In this prospective study, we evaluated pacing therapy in 60 consecutive patients affected by syncopes or pre-syncopes and cardioinhibitory or mixed carotid sinus hypersensitivity. We preferred DDD/DVI pacing for the 26 patients who had: 1) the cardioinhibitory form and presence of symptomatic pacemaker effect, or 2) the mixed type I form and presence of symptomatic pacemaker effect, ventriculo-atrial conduction, or orthostatic hypotension, or 3) the mixed type II form, or 4) the presence of severe sinus bradycardia. We preferred VVI mode in the other 34 patients. Syncope or pre-syncope persisted in one patient of the VVI group after the pacemaker implant and in one patient of the DDD/DVI group. Therefore, we obtained the suppression of severe symptoms in 97% of cases (58/60 pts). Yet minor symptoms persisted in 35% and 38% of patients of the two groups, respectively. No patient developed clinical signs of cardiac insufficiency or intolerance to pacing therapy. Besides, in DDD/DVI patients, we performed a single-blind, randomized, cross-over study for a comparison between the DDD/DVI and VVI mode: each patient was paced for two months using each mode and for each period symptoms were analyzed. The VVI period, compared to the DDD/DVI, resulted in a significantly higher incidence of symptoms: syncope 8% vs. 0%; pre-syncope 31% vs 0%; minor symptoms 58% vs. 31%; cardiac failure 19% vs. 0%. So the DDD/DVI mode was preferred by 69% of the patients.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[The choice of stimulation mode in patients with cardioinhibitory or mixed carotid sinus hypersensitivity, with or without associated sinus dysfunction]. 274 11

The results of haemodynamic, echocardiographic and bicycle exercise investigations in a 72-year-old man with a permanent complete atrioventricular block and heart failure following infarction are presented. Comparative measurements were obtained under the conditions of a ventricular and an av-sequential pacemaker (PM). The ventricular demand pacemaker (VVI) was implanted three years ago and because of further impairment of cardiac performance an av-sequential pacemaker (DDD) was used to restore atrio-ventricular synchronisation. The treatment with bifocal PM improved dramatically cardiac output and exercise capacity. The echocardiographic findings demonstrate the significance of Frank-Starling mechanism in this case due to better filling of the ventricles. As noninvasive methods, echocardiography and bicycle-exercise test allow long-term analysis of cardiac function.
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PMID:[Hemodynamic and exercise capacity in a 72 years old patient under a ventricular and bifocal pacemaker (author's transl)]. 725 4

To verify that atrioventricular (AV) synchronous pacing (DDD) with short AV delay improves the condition of patients with severe congestive heart failure, we implanted DDD pacemakers in 10 patients with severe heart failure (New York Heart Association [NYHA] class III to IV). One day after pacemaker implantation, the AV delay was optimized by Doppler echocardiographic measurements over the aortic outflow tract. Patients were evaluated regarding NYHA class, stroke volume, cardiac output, ejection fraction, and quality of life at 1, 3, and 6 months after pacemaker implantation. Although the optimized AV delay was associated with short-term improvement in stroke volume and cardiac output (baseline stroke volume = 22 +/- 7 ml, day 1 = 28 +/- 12 ml; p = 0.03: baseline cardiac output = 1.9 +/- 0.6 L/min, day 1 = 2.2 +/- 1.1 L/min; p = 0.10), the mean stroke volume, cardiac output, NYHA class, and ejection fraction did not change significantly after 1, 3, and 6 months of pacing compared with baseline values. Three patients improved in NYHA class during the follow-up. A consistent improvement in stroke volume, cardiac output, NYHA class, and ejection fraction was observed in only 1 patient. In conclusion, we found no beneficial effects of AV-synchronous pacing with optimized AV delay in patients with severe heart failure.
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PMID:Results of atrioventricular synchronous pacing with optimized delay in patients with severe congestive heart failure. 773 1

Between 1986 and 1992, pacemakers were implanted in 307 patients with symptoms caused by the sick sinus syndrome (SSS). 301 patients were regularly followed up (161 men, 146 women, mean age 72.9 [27-91] years) of whom 180 had a VVI, 65 and AAI and 58 a DDD/DDI pacemaker. Mean follow-up period was 58.3 months for VVI-stimulated patients and 35.6 months for atrial paced patients. The data were analysed retrospectively to ascertain whether a change in pacemaker treatment to a more physiological system produced any lowering in the mortality rate, incidence of permanent atrial fibrillation (AF), and thromboembolic phenomena. The annual mortality rate of the VVI-stimulated patients was 6.9%, that of atrial paced patients 2.8%. Age, abnormal ventricular function, survived resuscitation and diabetes mellitus each correlated with a shortened life expectancy already at the time of implantation, regardless of the pacemaker mode. Permanent AF was more frequent during VVI stimulation (16% vs 7%), especially if it had been preceded by intermittent AF (26% vs 13%). But there was no significant difference with regard to transitory cerebral ischaemic episodes and peripheral arterial emboli (15% vs 10%). Fewer patients with atrial pacing went into heart failure (20% vs 30%). Four patients developed a high-grade atrioventricular (a-v) block on AAI stimulation (annual incidence 2.4%). - These observations suggest that patients with SSS should always have atrial paced pacemaker systems. If a-v conduction is disturbed, a bifocal pacemaker is the system of choice.
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PMID:[Pacemaker therapy for the sick sinus node syndrome. Does the atrially involved pacemaker system lower the frequency of atrial fibrillation and thromboembolic complications as well as mortality?]. 798 73

In 20 patients we measured the increase in stroke volume at rest with DDD compared with VVI pacing, using pulsed Doppler echocardiography at a pacing rate of 70 beats min. By using the apical two-chamber window, the stroke volume was assessed by measuring the integral wave of flow at the level of the aortic anulus, also the most favourable A-V delay was determined. The increase of stroke was comprised within 25.3% and 48.6%. The patients with increased heart size (atrial or ventricular chamber) or ventricular thickness and clinical or echocardiographic signs of heart failure were excluded to avoid variables too and to have an homogeneous group. This study confirms the hemodynamic effects of ventricular pacing, with and without atrio-ventricular synchrony in patients with normal left ventricular function. Doppler technique is useful in non invasive assessment of cardiac output in patients with or without physiologic pacemakers.
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PMID:[Bicameral (DDD) vs. monocameral (VVI) stimulation: echo Doppler study]. 812 54


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