Early and late cardiac ventricular reverse remodeling after catheter ablation for lone paroxysmal atrial fibrillation.

AIM: We sought to explore ventricular function in patients with lone paroxysmal atrial fibrillation (AF) and determine the mid- and long-term impact of pulmonary vein isolation on cardiac remodeling. BACKGROUND: The relationship between tachyarrhythmia and ventricular dysfunction is still a matter of debate. Tachycardia-induced cardiomyopathy is defined as reversible myocardial dysfunction following treatment for tachyarrhythmia. METHOD: We prospectively studied 31 patients (56.4 ± 10 years) presenting with paroxysmal-AF who were treated successfully by catheter ablation and 15 age-matched controls. Left and right ventricular functions were assessed by echocardiography at baseline and at 3-month and 1-year follow-up. RESULTS: In AF-patients, LV-function was slightly lower at baseline than controls (LV-ejection fraction was 60% versus 64%; P = 0.06). More impressive, systolic peak velocity on Doppler tissue imaging was 9 cm/s in AF patients (versus 12 cm/s; P = 0.0004). LV global longitudinal strain was also significantly different between the two groups (patients: -16% versus controls: -19%; P = 0.005). At 1-year follow-up, most functional parameters significantly improved in the AF-patients and no longer differed from the controls. Right ventricular (RV) function was also depressed in AF patients at baseline. At 1-year follow-up, tissue Doppler showed improvement in RV-S' (+27%, P = 0.007) and RV peak systolic strain (+36%, P<0.0001) and became comparable to controls. CONCLUSION: We demonstrate that some degree of arrhythmic cardiomyopathy exists in patients presenting with lone paroxysmal-AF. Catheter ablation improved RV and LV functions. Longitudinal function is the most sensitive component of ventricular systole to monitor when looking for this cardiac reverse remodeling.

[Rate control or rhythm control]. / Contrôle du rythme sinusal ou contrôle de la fréquence ventriculaire?

Rhythm control or rate control are the 2 therapeutic strategies for atrial fibrillation (AF) management. Despite strong physiological and epidemiological data to support a rhythm control strategy, the results of the prospective studies, especially AFFIRM and RACE trials, did not demonstrate any superiority of a rhythm control versus a rate control strategy. The AF-CHF trial conducted in heart failure patients led to the same conclusions. In clinical practice, the therapeutic management is only driven by the patient symptoms. For rhythm control, antiarrhythmic drugs are still the first step before considering, in selected patients, ablative techniques. Treatment algorithms proposed in 2006 by the European society of cardiology are the references for patient management, treatment being individually optimized.

[Cardiac arrest outside hospital: initial and subsequent cardiological management]. / Arrêt cardiaque extrahospitalier: prise en charge initiale puis en milieu cardiologique.

UNLABELLED: The prognosis of cardiac arrest outside hospital is directly related to the initial management. The aim of this work was to evaluate the characteristics of the initial and subsequent cardiological management of victims of cardiac arrest outside hospital with a retrospective analysis of data from the SAMU 35 (Emergency Medical Service, IIIe et Vilaine region) in the period April 1998 - April 2002. RESULTS: 533 non-traumatic cardiac arrests outside hospital were reported in 532 patients (average age 63 +/- 17, 73% male). The cardiac arrest occurred at home in 77% of cases. The initial cardiac rhythm documented was asystole in 63% of cases, ventricular fibrillation (VF) in 30% ventricular tachycardia (VT) in 1% and electromechanical dissociation in 6%. A cardiac aetiology was presumed in 294 (69%) of the 424 resuscitated patients. Among these, 22% (66/294) were admitted to coronary care units, 11% (31) left hospital alive, 8% (24) with no neurological sequelae. The survival rate for patients with cardiac arrest outside hospital in the presence of a witness and for whom the initial rhythm was VF or VT was 21%. The patient's age (<60 years)[OR: 1.05; CI 95%: 1.02-1.07; p < 0.001], rapid arrival of the SAMU (<10 min) [OR: 5.68; CI 95%: 1.42-22.7; p = 0.01] and resuscitation by the witness (OR: 8.26; CI 95%: 3.28-20.83; p < 0.001) were factors predictive of survival in a multivariate analysis. Coronary heart disease remains the principal cause of cardiac arrest in patients admitted to cardiology units (68%), with a recent coronary thrombosis shown in 40% of patients undergoing angiography (16/40). CONCLUSION: the prognosis of cardiac arrest outside hospital remains bleak, with a mortality of 90%. The survival rate is higher if the initial management is optimal, associated with bystander resuscitation and an immediate emergency service response allowing rapid defibrillation. Diagnosis and management of acute coronary syndrome in a cardiological setting must be integrated into the strategy.

[Factor VIII hyperactivity: an arterio-venous thrombogenic factor. Case report]. / Hyperactivité du facteur VIII: un facteur thrombogène artério-veineux. A propos d'un cas.

Thrombosis is the principal mechanism in vascular pathology, whether cerebral, coronary or peripheral. During the initial stages of infarction, coagulation contributes to vascular occlusion, the haemostatic factors playing a determining role in the development of atherothrombotic lesions. An increase in a coagulation protein, besides any lowering of anticoagulation protein levels, is a risk factor for thrombosis. Among these pro-coagulant factors, the pro-thrombogenic action of factor VIII has without doubt been studied the least. We report the case of a 62 year old patient with a personal and family history of many previous thrombotic episodes, both arterial and venous, in whom factor VIII hyperactivity was discovered after a myocardial infarction. This case underlines the association of the factor VIII complex with thrombosis, and its clinical repercussions, especially the incidence of coronary pathology.

[The role of cardiac pacing in the treatment of atrial arrhythmias]. / Place de la stimulation cardiaque dans la prévention et le traitement des arythmies atriales.

The role of cardiac pacing in the treatment of atrial arrhythmias can be analysed from the angle of prevention or treatment in a strategy of rhythm control or heart rate control. From the heart rate control viewpoint, "ablate and place" is a validated method, especially in terms of mortality based on the results of large registers, in cases of uncontrolled ventricular rhythms causing symptoms or left ventricular dysfunction. In a strategy of rhythm control, the theoretical bases of prevention of atrial fibrillation (AF) by atrial pacing are convincing but the clinical results of different prospective clinical trials, though encouraging, do not provide formal proof of the efficacy of preventive pacing. Permanent 100% atrial pacing remains the objective which has led to the development of many algorithms evaluated in the ADOPT, AF Therapy, PIPAF, ATTEST...trials, with contradictory results. The choice of atrial pacing site seems to be a determining factor for the success of the method with better results seemingly with the high or low septal positions. The results of the OASES trial support this hypothesis but they were not confirmed by the ASPECT trial. An interesting observation was made in the PIPAF and a new Danish trial on the deleterious effects of ventricular capture when not required which is the rule in patients paced for brady-tachycardia syndromes. As for the role of anti-tachycardia pacing, the technique remains to be validated. Perhaps, the association of different techniques evaluated--the site of pacing, the prevention algorithms, respect of the ventricular rhythms, reduction by anti-tachycardia stimulation--will provide multifunction devices capable of best managing atrial arrhythmias which do not require "curative" therapy, and in particular, endocavitary ablation. In practice, it is generally when faced with brady-tachycardia syndromes that the question of the preventive role of pacing is raised. The problem is to choose the site of stimulation and the most appropriate pacing device in the light of current knowledge.

[Medium-term results of multisite biventricular stimulation in severe cardiac failure]. / Effets à moyen terme de la stimulation multisite biventriculaire dans l'insuffisance cardiaque sévère.

Since its introduction in cardiac failure in 1994, biventricular cardiac stimulation has been widely applied with many clinical trials and the development of new specific technology. The authors present the results observed in the first 125 consecutively implanted patients at the Rennes University Hospital. After a mean follow-up of 22 months, the mortality rate was 40%. The causes of death were sudden death in 42% of patients, progression of cardiac failure in 34% and non-cardiac in 24%. The functional benefits of biventricular cardiac stimulation were seen through significant improvement in HYHA Class, 3.3 +/- 0.5 before implantation to 2.3 +/- 0.8 at the end of follow-up, and by a significant increase of 40% of peak VO2 and of maximal duration of exercise. With the learning curve and development of new technology, the left ventricular catheterisation via a coronary sinus vein, increased from 56% to over 95% during the last two years with an acceptable rate of complications. These results, with the reserve of not being a controlled trial, show the feasibility, safety and efficacy of biventricular cardiac stimulation in terms of functional benefit. Clinical trials are currently underway to assess the impact of this method on morbi-mortality and to assess the concept in association with ventricular defibrillation.

Six year experience of transvenous left ventricular lead implantation for permanent biventricular pacing in patients with advanced heart failure: technical aspects.

BACKGROUND: Biventricular pacing has been proposed as an adjuvant to optimal medical treatment in patients with drug refractory heart failure caused by chronic left ventricular systolic dysfunction and intraventricular conduction delay. OBJECTIVE: To assess the technical feasibility and long term results (over six years) of transverse left ventricular pacing with the lead inserted into a tributary vein of the coronary sinus. SUBJECTS: From August 1994 to February 2000, left ventricular lead implantation was attempted in 116 patients who were eligible for biventricular pacing (mean (SD) age 67 (9) years, New York Heart Association (NYHA) functional class III/IV, left ventricular ejection fraction 22 (6)%, QRS duration 185 (26) ms). RESULTS: The overall implantation success rate was 88% (n = 102). A learning curve was indicated by a progressive increase in success from 61% early on to 98% in the last year. The mean pacing threshold was 1.1 (0.7) V/0.5 ms at the time of implantation and increased slightly up to 1.9 (0.9) V/0.5 ms at the end of the follow up period (15 (13) months). The rate of acute and delayed left ventricular lead dislodgement decreased from 30% in the early years to 11% after 1999. During follow up, 19 patients required reoperation for delayed lead dislodgement or increase in left ventricular pacing threshold (n = 15), phrenic nerve stimulation (n = 3), or infection (n = 3). CONCLUSIONS: Transverse left ventricular pacing through the coronary sinus is feasible and safe. The rate of implantation failure and of lead related problems has decreased greatly with increasing experience and with improvements in the equipment.

Long-term effects of biatrial synchronous pacing to prevent drug-refractory atrial tachyarrhythmia: a nine-year experience.

INTRODUCTION: Results of previous studies suggest that atrial resynchronization by multisite atrial pacing may contribute to prevention of recurrences in patients with drug-refractory atrial tachyarrhythmias and significant intra-atrial conduction delay. METHODS AND RESULTS: To verify this hypothesis, a prospective noncontrolled study of 86 patients (mean age 66 +/- 10 years) was conducted in a single center between January 1989 and February 1998. Inclusion criteria were P wave duration > or = 120 msec with interatrial conduction time > or = 100 msec, and history of multiple recurrences of atrial tachyarrhythmias (mean 7 +/- 4.8 episodes) evolving in a persistent mode for at least 6 months despite optimized drug treatment (mean 2.7 +/- 1.8 drugs/patient). Patients were chronically implanted with a pacing system that ensured permanent biatrial pacing using two atrial leads, one placed in the high right atrium and the other one into the mid or the distal part of the coronary sinus. P wave duration decreased from a mean value of 187 +/- 29 msec before implant to 106 +/- 14 msec (P < 0.0001) under biatrial pacing. After a 33-month mean follow-up (range 6 to 109), 55 patients (64%) remained in sinus rhythm, including 28 patients (32.6%) without any documented recurrence and 27 patients with one or more recurrences in a paroxysmal or in a persistent form. In these 55 patients, drug treatment was significantly reduced in relation to the preimplantation period (1.4 +/- 0.6 vs 1.7 +/- 0.5 drugs/patient; P = 0.011). The other 31 patients went into chronic atrial arrhythmia after a mean period of 26 months. The only predictive factor of positive response was a spontaneous P wave duration < 160 msec at baseline. CONCLUSION: The results are consistent with a preventive effect of permanent biatrial pacing on recurrent and drug-refractory atrial arrhythmias associated with intra-atrial conduction delay.

[Cardiac insufficiency: prevention of ventricular arrhythmias]. / Insuffisance cardiaque: prévention des arythmies ventriculaires.

Ventricular arrhythmias are particularly common in cardiac failure and their mechanisms are very complex. The prevention of these ventricular arrhythmias is only worthwhile if it results in benefits in terms of reduction of the risk of sudden death and in improvement in life expectancy. However, the relationship between complex ventricular arrhythmias and sudden death is far from established. The first problem is, therefore, to select the patients at high risk of sudden death. Unfortunately, there are no reliable markers of arrhythmic risk; only patients at low risk can be reasonably well identified on clinical and haemodynamic assessment and the results of ambulatory and signal averaged ECG. When an antiarrhythmic treatment seems to be required, the choice is very limited in practice. There is no role for Class I antiarrhythmics to play in this indication. Amiodarone, with its complex electrophysiological profile enabling an interaction with all potential mechanisms of ventricular arrhythmias, is a first-line drug in cardiac failure because of its efficacy and good myocardial tolerance. However, the benefits of amiodarone therapy in terms of reduction of global mortality have not been demonstrated, especially in view of the discordance between the results of the GESICA and CHF STAT trials. On the other hand, the value of betablockers, whether conventional molecules like bisoprolol (CIBIS II study) or metoprolol (MERIT-HF study), or molecules with a special profile such as carvedilol, has been clearly established. In association with conventional diuretics and angiotensin converting enzyme inhibitors, they reduce global mortality by about 35% and sudden death by 40%. However, the future possibly lies with non-pharmacological approaches such as the implantable defibrillator, at least in patients clearly identified as being at high risk of arrhythmic death, resuscitated from cardiorespiratory arrest due to documented ventricular fibrillation or presenting with haemodynamically poorly tolerated ventricular tachycardia. The automatic defibrillator could improve the prognosis of these patients, irrespective of their functional status (NYHA, Classes I, II or III). In practice, "rhythmological" management of cardiac failure cannot be dissociated from the haemodynamic and neuro-hormonal aspects of the affection, and only a multi-factorial approach is being realistic.

Comparative effects of permanent biventricular pacing for refractory heart failure in patients with stable sinus rhythm or chronic atrial fibrillation.

This study aimed to compare the long-term benefit of biventricular pacing in drug-refractory heart failure in patients with dilated cardiomyopathy who were in stable sinus rhythm or had persistent atrial fibrillation. The results showed that permanent biventricular pacing in such patients significantly improves exercise tolerance in both groups of patients; however, the benefit tended to be greater in patients with atrial fibrillation.

Electrocardiographic predictive factors of long-term clinical improvement with multisite biventricular pacing in advanced heart failure.

Biventricular pacing has recently been proposed for treating patients with drug refractory heart failure and intraventricular conduction delay. The purpose is to restore ventricular relaxation and contraction sequences as homogeneously as possible. The aim of this study was to determine if some factors could predict the long-term clinical effectiveness of that new treatment. This study included 26 patients, aged 66 +/- 7 years, with drug refractory heart failure and wide QRS. Patients were implanted with a biventricular pacemaker. The left ventricle was paced through a coronary sinus tributary. New York Heart Association functional class, exercise tolerance, and left ventricular (LV) ejection fraction were collected at baseline and after pacemaker implantation. Patients were divided into 2 groups: group I = responders; group II = nonresponders. QRS duration and axis at baseline and during biventricular pacing, interventricular conduction time, and LV and right ventricular lead positions were compared between the 2 groups. Group I patients (n = 19) had a mean reduction of 1.3 in functional class and an increase in peak oxygen consumption rate by a mean of 50%. The only parameter that differed between the 2 groups was the QRS duration during biventricular pacing, with a significantly shorter value in group I than in group II (154 +/- 17 vs 177 +/- 26 ms; p = 0.016). Thus, a positive response to biventricular pacing is correlated with the quality of electrical resynchronization. The optimal positions of the right and LV leads would be those that could induce the greatest shortening of QRS duration.

Pacemaker lead infection: echocardiographic features, management, and outcome.

OBJECTIVE: To compare transthoracic and transoesophageal echocardiography (TTE, TOE) in patients with permanent pacemaker lead infection and to evaluate the safety of medical extraction in cases of large vegetations. METHODS: TTE and TOE were performed in 23 patients with definite pacemaker lead infection. Seventeen patients without previous infection served as a TOE reference for non-infected leads. RESULTS: TTE was positive in seven cases (30%) whereas with TOE three different types of vegetations attached to the leads were visualised in 21 of the 23 cases (91%). Of the 20 patients with vegetations and lead culture, 17 (85%) had bacteriologically active infection. Left sided valvar endocarditis was diagnosed in two patients. In the control group, strands were visualised by TOE in five patients, and vegetations in none. Medical extraction of vegetations >/= 10 mm was performed in 12 patients and was successful in nine (75%) without clinical pulmonary embolism. After 31.2 (19.1) months of follow up (mean (SD)), all patients except one were cured of infection; three died from other causes. CONCLUSIONS: Combined with bacteriological data, vegetations seen on TOE strongly suggest pacemaker lead infection. Normal TTE examinations do not exclude this diagnosis because of its poor sensitivity. Medical extraction of even large vegetations appeared to be safe.

Effects of permanent dual-chamber pacing on mitral regurgitation in hypertrophic obstructive cardiomyopathy.

AIMS: To assess the effects of chronic dual-chamber pacing on mitral regurgitation in hypertrophic obstructive cardiomyopathy. METHODS AND RESULTS: Twenty-three patients with hypertrophic obstructive cardiomyopathy and mitral regurgitation. treated with DDD pacing for 16 +/- 14 months, were included in the study. Mitral regurgitation was assessed by Doppler-echocardiography using semi-quantitative analysis (grades I-IV) and by measuring the maximum regurgitant jet area/left atrial area ratio. At the end of follow-up, DDD pacing reduced the outflow gradient from 93 +/- 37 mmHg to 31 +/- 30 mmHg (P<0.0001). Nine of the 14 patients who initially had > or =grade II mitral regurgitation improved by at least one grade, two of them exhibiting dramatic improvement (from grade IV and III to grade I). The regurgitant jet area/left atrial area ratio was reduced with DDD pacing from 20 +/- 13% to 11 +/- 6% (P<0.0001). Patients who had significant mitral regurgitation despite pacing were those whose outflow gradient remained high or those with mitral valve organic abnormalities (mitral annulus calcification or mitral valve prolapse). In the absence of organic abnormalities other than leaflet elongation, there was a significant correlation between the gradient value achieved with DDD pacing and the extent of mitral regurgitation (P<0.05). CONCLUSION: In the absence of organic mitral valve abnormalities, DDD pacing reduces in parallel mitral regurgitation and left ventricular outflow gradient. In such patients therefore, significant mitral regurgitation is not a contraindication to pacing.

Optimal right ventricular pacing site in chronically implanted patients: a prospective randomized crossover comparison of apical and outflow tract pacing.

OBJECTIVES: To evaluate the long-term functional and hemodynamic effects of right ventricular outflow tract (RVOT) pacing by comparison with right ventricular apical (RVA) pacing. BACKGROUND: Acute studies have suggested that RVOT pacing could significantly improve cardiac performance in comparison with RVA pacing but no data are available in chronically implanted patients. METHODS: Sixteen patients with chronic atrial tachyarrhythmia and complete AV block were included. Left ventricular ejection fraction (LVEF) was > or =40% in ten and <40% in six. Patients were implanted with a standard DDDR pacemaker connected to two ventricular leads. A screw-in lead was placed at the RVOT and connected to the atrial port. A second lead was positioned at the RVA and connected to the ventricular port. Right ventricular outflow tract and RVA pacing was achieved by programming either the AAIR or the VVIR mode respectively. Four months later patients were randomized so as to undergo either RVOT or RVA pacing for three months according to a blind crossover protocol. Apart from the pacing mode, programming remained unchanged throughout the study. At the end of each period, NYHA class, LVEF, exercise time and maximal oxygen uptake were assessed. RESULTS: No significant difference was observed between the two modes for all the parameters analyzed. These identical results were observed in all patients globally, in patients with LVEF > or =40% as in those with LVEF <40%. CONCLUSIONS: Within the limits of this study, no symptomatic improvement or hemodynamic benefit was noted after three months of RVOT pacing, by comparison with RVA pacing.

Acute hemodynamic effects of biventricular DDD pacing in patients with end-stage heart failure.

OBJECTIVES: The aim of this study was to assess the potential acute benefit of multisite cardiac pacing with optimized atrioventricular synchrony and simultaneous biventricular pacing in patients with drug-refractory congestive heart failure (CHF). BACKGROUND: Prognosis and quality of life in severe CHF are poor. Various nonpharmacological therapies have been evaluated but are restricted in their effectiveness and applications. In the early 1990s, dual chamber pacing (DDD) pacing was proposed as primary treatment of refractory CHF but results were controversial. Recently, tests to evaluate the effect of simultaneous pacing of both ventricles have elicited a significant improvement of cardiac performance. METHODS: Acute hemodynamic study was conducted in 18 patients with severe CHF (New York Heart Association class III and IV) and major intraventricular conduction block (IVCB) (QRS duration = 170+/-37 ms). Using a Swan-Ganz catheter, pulmonary artery pressure, pulmonary capillary wedge pressure (PCWP) and cardiac index (CI) were measured in different pacing configurations: atrial pacing (AAI) mode, used as reference, single-site right ventricular DDD pacing and biventricular pacing with the right ventricular lead placed either at the apex or at the outflow tract. RESULTS: The CI was significantly increased by biventricular pacing in comparison with AAI or right ventricular (RV). DDD pacing (2.7+/-0.7 vs. 2+/-0.5 and 2.4+/-0.6 l/min/m2, p < 0.001). The PCWP also decreased significantly during biventricular pacing, compared with AAI (22+/-8 vs. 27+/-9 mm Hg; p < 0.001). CONCLUSIONS: This acute hemodynamic study demonstrated that biventricular DDD pacing may significantly improve cardiac performance in patients with IVCB and with severe heart failure, in comparison with intrinsic conduction and single-site RV DDD pacing.

Aneurysms and pseudoaneurysms of saphenous vein coronary artery bypass grafts.

Aneurysms of saphenous vein grafts to coronary arteries are unusual complications of coronary artery bypass graft (CABG) surgery. Three patients (men aged 47, 62, and 68 years) are presented with spontaneous chest pains 10, 21, and 17 years after CABG surgery. In one case, the saphenous vein graft had eroded into the right atrium and had established a fistula between the graft and the right atrium. Diagnosis of saphenous vein graft aneurysms was confirmed by echocardiography, computed tomography or magnetic resonance imaging, and by arteriography. Two patients were treated surgically, the third by percutaneous coil embolisation followed by balloon angioplasty of the right coronary artery.