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Query: UMLS:C0018801 (heart failure)
 72,216 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Because dual-chamber (DDD) pacing has been shown to be of benefit regarding symptoms, rest and pacing hemodynamics, and exercise duration in patients with obstructive hypertrophic cardiomyopathy (HC), the effect of DDD pacing was assessed in patients with nonobstructive HC who were significantly symptomatic despite medical management. Echocardiography, treadmill exercise testing, thallium-201 scintigraphy, radionuclide angiography, and invasive measurement of rest and semi-erect bicycle exercise hemodynamics were performed in 12 patients before and approximately 4 months after permanent DDD pacing. One patient died 3 months after pacemaker implantation, because of worsening diastolic heart failure. Of the remaining 11 patients, 10 improved regarding symptoms, and treadmill exercise duration was longer during DDD pacing than during the baseline study in sinus rhythm (6.8 +/- 2.8 to 8.5 +/- 2.8 minutes; p < 0.01), with a significant increase in the peak double product achieved (28.9 +/- 6.1 to 31.0 +/- 6.8 x 10(3); p < 0.05). However, there were significant reductions in cardiac (3.7 +/- 0.9 to 3.1 +/- 0.5 ml/min/m2; p < 0.01) and stroke volume (47.4 +/- 11.4 to 38.7 +/- 6.5 ml/beat/m2; p < 0.01) indexes, and a trend toward reduction in submaximal stroke volume index during DDD pacing as compared with the baseline study in sinus rhythm (44.7 +/- 13.5 to 40.9 +/- 10.9 ml/beat/m2; p = 0.097). No change in peak heart rate, cardiac or stroke volume index, mean blood pressure, or pulmonary artery or pulmonary capillary wedge pressure occurred with peak exercise during DDD pacing as compared with the initial exercise study in sinus rhythm.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Results of permanent dual-chamber pacing in symptomatic nonobstructive hypertrophic cardiomyopathy. 814 3

A 27-year-old woman with systemic lupus erythematosus and Wolff-Parkinson-White syndrome complicated with refractory tachycardia and class III heart failure treated with pacemaker implantation was described. She had cardiomyopathy that could be due to lupus erythematosus or tachycardia-induced. Nonpharmacologic therapeutic alternative was used and a universal DDD pulse generator with selected programming was chosen. Twenty-four months follow-up showed tachycardia control and regression of symptoms of heart failure to class I as well as improvement of left ventricular function evaluated by echocardiographic method. Thus, pacemaker implant may be an useful alternative approach in patients with tachycardiomyopathy in whose other nonpharmacologic therapeutic options could not be performed.
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PMID:[Regression of tachycardiomyopathy after implant of pacemaker with antitachycardial function]. 824 39

The benefits of dual (DDD) over single chamber pacing (VVI) have been demonstrated in haemodynamics, exercise capacity, quality of life and reduced complications in atrioventricular block and sick sinus syndrome. The literature was reviewed to provide complication rates for dual and VVI pacing. Cost calculations were based on United Kingdom 1991 prices. Over a 10-year period, a computer model calculated the incidence and prevalence of atrial fibrillation, stroke, permanent disability, heart failure and mortality in six patient categories: sick sinus syndrome paced VVI, sick sinus syndrome upgraded to DDD, sick sinus syndrome paced DDD from outset, atrioventricular block paced VVI and those upgraded to DDD and atrioventricular block paced initially DDD. Calculations were based on intention to treat. The 10 year survival with DDD vs VVI pacing was 71% vs 57% in sick sinus syndrome and 61% vs 51%, respectively, in atrioventricular block. In both indications the prevalence of heart failure in the 10 year survivors was 60% lower with DDD pacing. In sick sinus syndrome patients paced VVI, 36% had severe disability while only 8% experienced this with DDD pacing. For atrioventricular block the figures were, respectively, 22% vs 3%. The difference in 10 year cumulative cost between VVI and DDD is 13 times the purchase price of a VVI pulse generator for sick sinus syndrome and 7 times for atrioventricular block. In the third year after implantation the cumulative costs of DDD were lower than for VVI for both indications. Dual chamber pacing for both indications, sick sinus syndrome and atrioventricular block, is both clinically and cost effective.
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PMID:Cost benefit analysis of single and dual chamber pacing for sick sinus syndrome and atrioventricular block. An economic sensitivity analysis of the literature. 1054 18

There has recently been an increasing interest in beneficial effects of cardiac pacing in patients with myocardial diseases, especially in Obstructive Hypertrophic and Dilated Cardiomyopathy. The experience with dual-chamber pacing for obstructive hypertrophic cardiomyopathy is now important. DDD pacing for sinus rhythm patients and VVI pacing in patients with atrial fibrillation have shown considerable symptomatic improvement, with a significant decrease of angina, dyspnea, presyncope and frank syncope. It has been suggested that DDD pacing may prevent sudden death and improve survival rates in these patients, but this has not yet been established. The experience with DDD pacing in dilated cardiomyopathy is more limited, but in specially chosen patients, DDD pacing with short AV delay has shown symptomatic improvement and a decrease in the need for further hospitalization due to worsening of heart failure. There is no current evidence of higher survival rates with this treatment, but DDD pacing may be used in patients with end-stage dilated and isquemic cardiomyopathy who are waiting for a heart transplantation.
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PMID:[Impact of electric cardiac stimulation on ventricular function and the natural history of patients with myocardiopathy]. 875 4

Drug therapy is the standard therapy for heart failure. The current state of the art does not permit pacemaker therapy as a general recommendation for left ventricular failure. Numerous controversial reports have been published on the success of pacemaker therapies for congestive heart failure. Iskandrian reported on tachycardiac atrial stimulation in 1986. Since 1990 several papers have been published on DDD-pacemakers with short AV-time. From the data available to us, congestive heart failure is generally not considered a new pacemaker indication. In carefully selected patients, however, an improvement in hemodynamics as well as in NYHA-classification can be expected, both in acute cases and on a long-term basis. In 16 patients Hochleitner demonstrated a significant increase in left ventricular ejection fraction, a significant drop in NYHA-classification, heart size and an increase in systolic and diastolic blood pressure. Using echocardiography Brecker showed a decrease in mitral regurgitation, an increase in ventricular filling time and, by means of ergometry, a major increase in cardiac output. The hypothesis for the working mechanism is that a shorter AV-time optimizes the time needed for AV-contraction, thereby reducing mitral regurgitation, lengthening ventricular filling time and thus increasing ejection fraction. Identification of the patients to whom this hypothesis can be applied is difficult but imperative. The optimal AV-time for each patient must be established on an individual basis using echocardiography, Doppler sonography and ergometry and must be finetuned in follow-up controls. Optimization of AV-time in patients with the classic indications for a pacemaker as well as a combination of cardioverters and DDD-pacemakers should be aimed for in patients with congestive heart failure and high NYHA-classification.
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PMID:[Pacemaker therapy in heart failure]. 965

In view of the large number of inappropriate shocks observed in patients with implanted defibrillators, improved detection of ventricular arrhythmias has become a major objective. The addition of an atrial catheter has been proposed to improve discrimination between ventricular and non-ventricular arrhythmias. Besides this function, the additional catheter could be used for DDD pacing without risk of interaction between the pacemaker and defibrillator. The authors report their initial experience in 16 patients implanted with a DDD pacemaker. The indication was resuscitated sudden death (N = 5) or ventricular tachycardia (N = 11). The choice of a DDD defibrillator was justified by a bradycardia (N = 9), haemodynamic factors (N = 4) or supraventricular tachycardia (N = 3). The devices used were the Defender 9001 (ELA Medical SA, France, N = 3), the Ventak AV 1810 and the Ventak AV II DR 1821 (Guidant/CPI, Inc. USA, N = 11 and N = 2 respectively). There were three immediate complications. After 2 to 29 months' follow-up, 5 patients had received appropriate treatment by their devices. Five patients had inappropriate shocks : one patient received a shock triggered by electrical interference, two others had no active sensing algorithme when the shocks were delivered, and the other two had an activated algorithme with 1/1 conduction of a supraventricular arrhythmia. No recurrences were recorded after reprogramming the device. DDD or VDD pacing was permanent in 9 patients and intermittent in 3 others. Seven patients had dilated cardiomyopathy and severe cardiac failure and were clinically improved by dual chamber pacing. In many patients, candidates for a defibrillator, this new generation of devices has improved specificity of arrhythmia detection and cardiac pacing without risk of interaction. The authors propose a classification of the indications for a DDD defibrillator.
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PMID:[Dual-chamber implantable automatic defibrillators. Experiences apropos of 16 cases]. 974 90

Dual-chamber pacing may improve short-term hemodynamics and functional class in some patients with congestive heart failure, even in the absence of conventional indications for pacemaker implantation. However, the impact of different pacing modes on survival of patients with congestive heart failure is controversial. In this retrospective study we analyzed survival data from 546 elderly patients, aged 70 years and older, who underwent implantation of a permanent dual-chamber (DDD, n = 62, DVI, n = 102) or single-chamber (VVI) pacemaker (n = 382) between 1980 and 1985. Survival was further analyzed according to the presence of absence of congestive heart failure, and pacemaker mode (DDD vs. DVI vs. VVI). Overall, dual-chamber pacing (DDD and DVI) was associated with a more favorable long-term outcome when compared with single-chamber ventricular pacing, although differences were only significant for DDD pacing (P = 0.002). When patients with and without preexisting congestive heart failure were analyzed separately, survival following dual-chamber pacing (DDD and DVI) was significantly better than survival following single-chamber pacing in patients without congestive heart failure (P = 0.03), but not in patients with preexisting heart failure (P = 0.139). When patients were analyzed according to the electrophysiological indication for pacemaker implantation, overall survival of patients with AV block (P = 0.0025) but not sinus node dysfunction (P = 0.346) was improved with dual-chamber pacing. This survival advantage in patients with AV block following dual-chamber pacing was lost in the presence of heart failure (P = 0.11). These findings suggest that dual-chamber pacing, in particular DDD pacing, improves the survival in elderly patients without preexisting congestive heart failure. In contrast to the short-term hemodynamic improvement observed in selected patients with congestive heart failure, dual-chamber pacing in elderly patients with congestive heart failure, paced for conventional indications, is not associated with improved survival when compared with single-chamber ventricular pacing.
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PMID:Pacing mode and long-term survival in elderly patients with congestive heart failure: 1980-1985. 986 71

Effectiveness of dual-chamber pacing in patients with dilated cardiomyopathy is still controversial. Our study was performed: to select the most favorable individual atrioventricular (AV) delay; to compare hemodynamic short-term effects in each patient after 2 periods of DDD pacing and sinus rhythm (AV spontaneous); to assess hemodynamic long-term (1 year) effects after DDD pacing at optimum AV delay. In 1996, 9 patients (7 men, 2 women; mean age 69 +/- 5 years) with dilated cardiomyopathy (5 idiopathic, 4 ischemic), NYHA functional class III-IV, ejection fraction < 30%, end-diastolic volume > 60 ml/m2, mitral regurgitation +2/+3, PR interval > or = 200 ms, were enrolled. All patients were implanted with DDD pacemakers and monitored for: ejection fraction and end-diastolic volume (measured by echocardiography and radionuclide angiography); clinical conditions; exercise tolerance and maximum oxygen consumption (by Weber exercise protocol); neurohormonal activity (plasma renin, aldosterone, atrial natriuretic factor). Data were recorded: before DDD implantation; after 2 randomized, single-blind periods of 3 months in VVI mode (at ventricular "sentinel" rate of 50 b/min) and in DDD mode with the optimum AV delay, corresponding for each patient to the minimum end-diastolic volume measured by radionuclide angiography and to the highest cardiac output recorded by echocardiography; after 6 months of DDD pacing with most favorable AV delay. Three more patients died 6 months after (between sixth and twelfth month of follow-up), due to refractory heart failure; 1 patient dropped out because his pacemaker was programmed in VVI mode at low rate, due to intolerance of DDD pacing. Among the other 4 patients no clinical and laboratory parameters were significantly different after 1 year of follow-up. In conclusion, DDD pacing in selected patients with dilated cardiomyopathy showed disappointing results, despite a strict and laboratory monitoring; DDD pacing could be of major benefit in larger populations, according to Doppler mitral flow pattern: those patients with a larger A-wave amplitude could be more sensitive to DDD pacing than those with evidence of poor atrial systole. Moreover, biatral and/or biventricular pacing could also play a significant role.
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PMID:[Dual-chamber DDD pacing in NYHA III-IV functional class dilated cardiomyopathy: short and middle-term evaluation]. 998 41

Dual chamber pacing has been proposed as an alternative treatment to patients with cardiac failure refractory to optimal medical therapy. The influence of the site of ventricular pacing was studied in 15 patients with an average age of 68.7 +/- 8.7 years with dilated cardiomyopathies and an average left ventricular ejection fraction of 22.3 +/- 6.8%. Three temporary USCI electrodes were positioned in the right atrium, the right ventricular outflow tract (RVOT) and the right ventricular apex. The average duration of the QRS complexes and the haemodynamic parameters (PAP, PCP and cardiac index) were measured in sinus rhythm and during DDD apical, RVOT and simultaneous apical and RVOT pacing. The RVOT and simultaneous pacing significantly reduced the QRS duration (135 +/- 14 ms and 137 +/- 17 ms, p < 0.0001 respectively) compared with apical pacing (150 +/- 19 ms). The mean PAP and mean PCP remained unchanged in the different modes of pacing but the cardiac index increased significantly during RVOT pacing (2.99 +/- 0.67 l/min/m2) and simultaneous pacing (3 +/- 0.77 l/min/m2) compared with apical pacing (2.66 +/- 0.62 l/min/m2) (p < 0.001 and p < 0.01 respectively) and compared with sinus rhythm (2.62 +/- 0.7 l/min/m2) (p < 0.001 and p < 0.005 respectively). This study suggests that better results may be obtained with RVOT screw in lead than with the traditional right ventricular apical electrode.
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PMID:[Comparison of apical and infundabular pacing in patients with primary dilated or ischemic cardiomyopathy]. 1006 78

Since the early nineties, the employment of DDD pacing from a right ventricular site with a short AV delay in patients with severe heart failure has led to considerable conflicting results, so that the real benefit of this method remains to be defined even in selected patients, such as those with first-degree AV block, QRS duration > 140 ms due to left bundle branch block (LBBB), mitral regurgitation time > or = 450 ms and diastolic filling time < or = 200 ms. Indeed, the asynchronous activation induced by pacing the right apex is the most important limitation to the technique, particularly in patients without an LBBB pattern or in those with an incomplete LBBB pattern. Recent studies have also shown that pacing of the right interventricular septum provides no better results than pacing of the right apex, at least in selected patients with no LBBB pattern and no significant mitral regurgitation. Today, it has been suggested that permanent biventricular pacing could be proposed as a feasible and reliable approach to improving ventricular function through the synchronization of the septum and the apex of the left ventricle, particularly in patients with a marked delay in ventricular activation sequence. This technique may be performed by means of transvenous leads inserted through the coronary sinus into the cardiac veins to stimulate both ventricles simultaneously, starting from the right apex and left lateral wall. Consequently, this approach supplies a strong basis for initiating further studies to examine the chronic effects of left ventricular pacing in patients with severe heart failure. We also suggest that the new tissue Doppler imaging techniques could usefully be applied to accurately select candidates to biventricular pacing.
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PMID:Multisite stimulation in refractory heart failure. 1032 26


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