Asystole episodes and bradycardia in patients with end-stage renal disease.

BACKGROUND: Knowledge of arrhythmias in patients with end-stage renal disease (ESRD) is mainly based on ambulatory electrocardiography (ECG) studies and observations during haemodialysis (HD). We used insertable cardiac monitors (ICMs) to define the prevalence of arrhythmias, focusing on bradyarrhythmias, in ESRD patients treated with several dialysis modes including home therapies. Moreover, we assessed whether these arrhythmias were detected in baseline or ambulatory ECG recordings. METHODS: Seventy-one patients with a subcutaneous ICM were followed for up to 3 years. Asystole (≥4.0 s) and bradycardia (heart rate <30 bpm for ≥4 beats) episodes, ventricular tachyarrhythmias and atrial fibrillation (AF) were collected and verified visually. A baseline ECG and a 24- to 48-h ambulatory ECG were recorded at recruitment and once a year thereafter. RESULTS: At recruitment, 44 patients were treated in in-centre HD, 12 in home HD and 15 in peritoneal dialysis. During a median follow-up of 34.4 months, 18 (25.4%) patients had either an asystolic or a bradycardic episode. The median length of each patient's longest asystole was 6.6 s and that of a bradycardia 13.5 s. Ventricular tachyarrhythmias were detected in 16 (23%) patients, and AF in 34 (51%) patients. In-centre HD and Type II diabetes were significantly more frequent among those with bradyarrhythmias, whereas no bradyarrhythmias were found in home HD. No bradyarrhythmias were evident in baseline or ambulatory ECG recordings. CONCLUSIONS: Remarkably many patients with ESRD had bradycardia or asystolic episodes, but these arrhythmias were not detected by baseline or ambulatory ECG.

Fluid overload is an independent predictor of atrial fibrillation in end-stage renal disease: A prospective study using insertable cardiac and body composition monitors
.

BACKGROUND: Fluid overload and atrial fibrillation (AF) are frequently encountered in patients with end-stage renal disease (ESRD). We used subcutaneously insertable cardiac monitors (ICM) to detect AF and associated it with the hydration status, determined with a body composition monitor (BCM) in dialysis patients. MATERIALS AND METHODS: 69 patients were recruited. Fluid overload was defined based on BCM measurements as a ratio of overhydration (OH) and extracellular water (OH/ECW) of > 15% at baseline. AF episodes lasting ≥ 2 minutes were collected. RESULTS: 45 in-center hemodialysis patients, 11 on peritoneal dialysis, 12 on home hemodialysis, and 1 predialysis-stage patient were followed up for a median of 2.9 years (25th - 75th percentile 1.9 - 3.1). 29% were overhydrated at baseline, and the percentage remained similar throughout the study. Overhydrated patients had a lower body mass index, a higher prevalence of type 1 diabetes mellitus (DM) and diabetic nephropathy, higher systolic blood pressure, greater ultrafiltration (UF) during dialysis, and a smaller lean tissue index than normohydrated patients. Chronic or paroxysmal AF was known to occur in 20.3% at entry, and a further 33.3% developed AF during the study, with an overall prevalence 53.6%. In univariable logistic regression, OH/ECW > 15% was strongly associated with AF prevalence (OR 6.8, 95% CI 1.7 - 26.5, p = 0.006), as were UF, age, coronary heart disease (CHD), DM, and the echocardiogram-derived ejection fraction and left atrial diameter. In multivariable analyses, OH/ECW > 15% remained an independent predictor of AF alongside age and CHD. CONCLUSION: The occurrence of AF is independently associated with BCM-measured fluid overload, which is common among ESRD patients.

Renal sympathetic denervation for treatment of patients with heart failure: summary of the available evidence.

Heart failure syndrome results from compensatory mechanisms that operate to restore - back to normal - the systemic perfusion pressure. Sympathetic overactivity plays a pivotal role in heart failure; norepinephrine contributes to maintenance of the systemic blood pressure and increasing preload. Cardiac norepinephrine spillover increases in patients with heart failure; norepinephrine exerts direct toxicity on cardiac myocytes resulting in a decrease of synthetic activity and/or viability. Importantly, cardiac norepinephrine spillover is a powerful predictor of mortality in patients with moderate to severe HF. This provided the rationale for trials that demonstrated survival benefit associated with the use of beta adrenergic blockers in heart failure with reduced ejection fraction. Nevertheless, the MOXCON trial demonstrated that rapid uptitration of moxonidine (inhibitor of central sympathetic outflow) in patients with heart failure was associated with excess mortality and morbidity, despite reduction of plasma norepinephrine. Interestingly, renal norepinephrine spillover was the only independent predictor of adverse outcome in patients with heart failure, in multivariable analysis. Recently, renal sympathetic denervation has emerged as a novel approach for control of blood pressure in patients with treatment-resistant hypertension. This article summarizes the available evidence for the effect of renal sympathetic denervation in the setting of heart failure. Key messages Experimental studies supported a beneficial effect of renal sympathetic denervation in heart failure with reduced ejection fraction. Clinical studies demonstrated improvement of symptoms, and left ventricular function. In heart failure and preserved ejection fraction, renal sympathetic denervation is associated with improvement of surrogate endpoints.

[Update on current care guideline: atrial fibrillation]. / Eteisvärinä.

The prevalence and incidence of atrial fibrillation (AF) are increasing rapidly. Key recommendations in management of AF include prompt administration of oral anticoagulation to all patients with elevated risk of thromboembolic complications, proper use of antiarrhythmic drugs and invasive therapies in highly symptomatic patients and adequate rate control in patients with permanent AF. The selection between warfarin and the novel oral anticoagulants (apixaban, dabigatran, rivaroxaban) is based on careful evaluation of the benefits and disadvantages of the drugs in a given patient.

Predictors of pocket hematoma in patients on antithrombotic therapy undergoing cardiac rhythm device implantation: insights from the FinPAC trial.

BACKGROUND: The FinPAC trial showed that the strategy of uninterrupted oral anticoagulation (OAC) was non-inferior to interrupted OAC for the primary outcome of bleeding and thromboembolic complications in patients undergoing cardiac rhythm management device (CRMD) implantation. METHODS: We conducted a post hoc analysis of the FinPAC data to explore the incidence and predictors of significant (> 100 cm(2)) pocket hematoma after CRMD implantation among the study population (n = 447). A total of 213 patients were on OAC, 128 were on aspirin, and 106 on no antithrombotic therapy. RESULTS: The incidence of significant pocket hematoma during hospital stay was significantly higher among patients using OAC (5.6%) and aspirin (5.5%) than in those with no antithrombotic medications (0.9%), but only one patient (0.8%) in the aspirin group needed revision of hematoma. Two patients (0.9%) in the OAC group and one (0.8%) in the aspirin group needed blood products. In multivariable regression analysis, no pre- procedural features predicted the significant hematoma in any of the groups. CONCLUSIONS: Clinically significant pocket hematoma is a rare complication after CRMD implantation in patients with ongoing therapeutic OAC. The incidence of significant pocket hematoma formation is similar in patients using OAC and those using aspirin.

Safety of pacemaker and implantable cardioverter-defibrillator implantation during uninterrupted warfarin treatment--the FinPAC study.

BACKGROUND: Periprocedural management of oral anticoagulation (OAC) in patients undergoing cardiac rhythm management (CRM) device implantation is controversial. Prior studies demonstrate that uninterrupted OAC may be safe, but limited data from randomized trials exist. METHODS: We conducted a multicenter, randomized trial to evaluate the safety of uninterrupted OAC during CRM device implantation. Patients on long-term warfarin (N=213) treatment with contemporary indication for CRM device implantation were randomized to uninterrupted versus interrupted (2 days) OAC therapy. The primary outcome included major bleeding events necessitating additional intervention and thromboembolic events during 4 weeks follow-up. RESULTS: The randomized groups were well matched in terms of bleeding and thromboembolic risk. Only one (1%) patient in the uninterrupted OAC group (N=106) needed blood transfusion due to rupture of proximal cephalic vein. Large hematomas were detected in 6% of patients in both groups, but there was no need for pocket revision in either group. Any pocket hematoma was observed in 35 patients (33%) in the uninterrupted OAC group and in 43 patients (40%) with interrupted OAC and uninterrupted OAC strategy was non-inferior to interrupted OAC (HR 0.86, 95%, p=0.001 for non-inferiority). One patient with interrupted OAC had stroke 3 days after the procedure. Hospital stay was comparable in all patient groups. CONCLUSION: Our randomized study demonstrates that CRM devices can be safely implanted without discontinuation of warfarin treatment.

[Thoracoscopic ablation of atrial fibrillation]. / Eteisvärinän torakoskooppinen ablaatiohoito.

Atrial fibrillation is often a disabling arrhythmia which can be alleviated by ablation procedures. The cornerstone procedure pulmonary vein isolation is generally performed using a transvenous approach transseptally. Endocardial technique can cause as complications arterial embolisation, pulmonary vein stenosis and oesophageal damage. Endocardial isolation has to be repeated often without predictable outcome. Pulmonary vein isolation can be performed with beating heart also mini-invasively in a thoracoscopic way. The procedure is suggested to be combined with ganglionated plexus ablation and resection of left atrial appendage. The results of both endocardial and epicardial isolation of pulmonary veins (hybrid therapy) have been promising. These two techniques are not competing with each other but are complementary. The epicardial procedure has more complications and the choice of therapy line should be considered carefully.

Microwave Ablation in Mitral Valve Surgery for Atrial Fibrillation (MAMA).

Objective: Microwave ablation in conjunction with open heart surgery is effective in restoring sinus rhythm (SR) in patients with atrial fibrillation (AF). In patients assigned for isolated mitral valve surgery no prospective randomized trial has reported its efficacy. Methods: 70 patients with longlasting AF where included from 5 different centres. They were randomly assigned to mitral valve surgery and atrial microwave ablation or mitral valve surgery alone. Results: Out of 70 randomized, 66 and 64 patients were available for evaluation at 6 and 12 months. At 12 months SR was restored and preserved in 71.0 % in the ablation group vs 36.4 % in the control group (P=0.006), corresponding figures at 6 months was 62.5 % vs 26.5 % (P=0.003). The 30-day mortality rate was 1.4 %, with one death in the ablation group vs zero deaths in the control group. At 12 months the mortality rate was 7,1 % (Ablation n=3 vs Control n=2). No significant differences existed between the groups with regard to the overall rate of serious adverse events (SAE) during the perioperative period or at the end of the study. 16 % of patients randomized to ablation were on antiarrhytmic drugs compared to 6 % in the control group after 1 year (p=0.22). Conclusion: Microwave ablation of left and right atrium in conjunction with mitral valve surgery is safe and effectively restores sinus rhythm in patients with longlasting AF as compared to mitral valve surgery alone.

Increased B-type natriuretic Peptide concentration is associated with reduced coronary vasoreactivity in patients with dilated cardiomyopathy but not in healthy young subjects.

Background/Aims. Natriuretic peptides are associated with the cardiovascular disease risk under a range of different circumstances. However, less is known about whether this association is found also in young healthy subjects. Methods. 9 patients with dilated cardiomyopathy and 26 healthy young subjects were studied. The myocardial blood flow measurements were performed basally and during adenosine infusion using PET. Results. S-proBNP concentrations were significantly higher (2153 ± 1964 versus 28 ± 17 ng/L, P = .000002) and adenosine-stimulated flow lower (1.6 ± 0.8 versus 3.6 ± 1.1 mL·g(-1)·min(-1), P = .00001) in patients with dilated cardiomyopathy when compared to healthy subjects. S-proBNP concentration was inversely associated with adenosine stimulated flow in patients with dilated cardiomyopathy (r = -0.75, P = .019) but not in healthy subjects (r = -0.06, P = .84). Conclusions. Natriuretic peptides are inversely associated with coronary vasoreactivity in patients with dilated cardiomyopathy but not in healthy young subjects. Since reduced coronary vasoreactivity seems to be one of the earliest abnormalities in the development of coronary artery disease, this might indicate that natriuretic peptides are not predictor of cardiovascular disease risk in healthy young subjects.

Clinical and laboratory risk factors of thrombotic complications after pacemaker implantation: a prospective study.

AIMS: Venous lesions, including obstruction and thromboembolism (VTE), are not uncommon after pacemaker implantation. The purpose of this prospective study was to assess the role of various patient and procedure-related risk factors in the development of these complications. METHODS AND RESULTS: A prospective venography-based study of 150 consecutive pacemaker implantations with a 6-month follow-up was conducted. Current case-control study included all cases (n = 47) with a new venous lesion, and their matched controls. Several surgical and technical factors, i.e. lead burden, choice of venous access, operator experience and procedure duration, as well as patient-related classic risk factors of VTE were assessed. Plasma markers of coagulation and endothelial activation [prothrombin fragment 1 + 2 (F1 + 2), D-dimer (DD), von Willebrand factor (vWF), thrombomodulin (Tm)] were used to evaluate the extent of acute surgical trauma. All cases with venous lesions were also screened for thrombophilia. None of the procedure-related variables were predictive of VTE. Mean levels of vWF, F1 + 2 and DD increased significantly (P < 0.001) and equally in both cases and controls. No single clinical factor predicted venous lesions, but significant (P < 0.05) clustering of classic clinical VTE risk factors was seen among the cases. Thrombophilia was overrepresented in patients with symptomatic pulmonary embolism (2/5, 40%). CONCLUSION: Pacemaker implantation induces a transient hypercoagulable state, but its degree does not predict subsequent venous thromboembolism, and neither did the grade of endothelial damage as reflected by plasma markers. The aetiology of these lesions seems to be multifactorial, and clustering of classic thrombotic risk factors plays a role in the pathogenesis.

The effect of right ventricular pacing on myocardial oxidative metabolism and efficiency: relation with left ventricular dyssynchrony.

PURPOSE: Right ventricular (RV) apical pacing induces dyssynchrony by a left bundle branch block type electrical activation sequence in the heart and may impair left ventricular (LV) function. Whether these functional changes are accompanied by changes in myocardial perfusion, oxidative metabolism and efficiency, and the relation with the induction of LV dyssynchrony are unknown. Our study was designed to investigate the acute effects of RV pacing on these parameters. METHODS: Ten patients with normal LV ejection fraction and VVI/DDD pacemaker were studied during AAI pacing/sinus rhythm without RV pacing (pacing-OFF) and with RV pacing (pacing-ON) at the same heart rate. Dynamic [15O]water and [11C]acetate positron emission tomography was used to measure perfusion and oxidative metabolism (kmono) of the LV. An echocardiographic examination was used to assess LV stroke volume (SV) and LV dyssynchrony. Myocardial efficiency of forward work was calculated as systolic blood pressure × cardiac output/LV mass/kmono. RESULTS: RV pacing decreased SV in all subjects (mean decrease 13%, from 76 ± 7 to 66 ± 7 ml, p = 0.004), but global perfusion and kmono were unchanged. The efficiency tended to be lower with pacing-ON (70 ± 20 vs 81 ± 21 mmHg l/g, p = 0.066). In patients with dyssynchrony during pacing (n = 6) efficiency decreased by 23% (from 78 ± 25 to 60 ± 14 mmHg l/g, p = 0.02), but in patients without dyssynchrony no change in efficiency was detected. Accordingly, heterogeneity in myocardial perfusion and oxidative metabolism was detected during pacing in patients with dyssynchrony but not in those without dyssynchrony. CONCLUSION: RV pacing resulted in a significant decrease in SV. However, deleterious effects on LV oxidative metabolism and efficiency were observed only in patients with dyssynchrony during RV pacing.

Progression of venous pathology after pacemaker and cardioverter-defibrillator implantation: A prospective serial venographic study.

BACKGROUND AND AIMS: Prospective data on development of venous obstruction after electrode implantation are limited. We performed a prospective study on 150 patients undergoing first pacemaker implantation. METHODS: Venographies at base-line and 6 months postimplantation in all patients, 50 patients included into a long-term follow-up of a mean of 2.4 years after implantation. RESULTS: At 6 months 14% had obstructions, but only 1 patient (0.7%) developed acute symptomatic upper extremity venous thrombosis. Pulmonary embolism (PE) was encountered in 5 (3.3%). After 6 months only 2 patients experienced pain in ipsilateral arm, but none had edema of arm, neck or head, or clinical PE. The 5 patients with total venous occlusion (TVO) at 6 months had no localized symptoms. Late venographic abnormalities developed in 5 (10%) patients: 4 TVOs and 1 stenosis. Two of the new lesions developed among 25 patients with normal 6-month venograms. Overall, TVO was detected in 9 of 150 patients. No factors emerged as independent predictors of total occlusion in multiple regression analysis. CONCLUSIONS: TVO is not uncommon after pacemaker implantation, and mostly occurs without any localizing symptoms. Most venous lesions seem to develop during the first months postimplantation, but late and unpredictable TVO may also occur.

No evidence of automatic atrial overdrive pacing efficacy on reduction of paroxysmal atrial fibrillation.

AIMS: Paroxysmal atrial fibrillation (PAF) is frequently encountered in pacemaker patients, most commonly in sick sinus syndrome. The combination of site-specific pacing in conjunction with an overdrive algorithm combined with antiarrhythmic drugs on the incidence of PAF in patients with a conventional indication for pacing is unknown. METHODS AND RESULTS: Patients with pacemaker indication and PAF received a DDDR-pacemaker, which included an automatic atrial overdrive (AO) algorithm. The atrial lead was implanted in either the right atrial appendage (RAA) (n = 83) or the right low-atrial septum (LAS) (n = 94). The algorithm was switched on or off in a 3 month, single blind crossover design and antiarrhythmic drugs were kept stable. A control group of 96 patients (LAS, n = 14; RAA, n = 84) without PAF served as controls to assess any proarrhythmic effect of overdrive pacing. Atrial fibrillation (AF) burden defined as cumulative time in mode switch was not reduced during automatic AO from either the RAA or from the LAS. The reduction was not effective both for AF of short (<24 h) and long (> or =24 h) duration. There was no atrial proarrhythmia induced by the overdrive algorithm in the control group. CONCLUSIONS: We could not demonstrate a reduction of AF burden defined as cumulative time in AF by the AO algorithm, in patients who are paced for standard indications and PAF, neither from the RAA nor from the LAS.

Thoracoscopic microwave ablation of atrial fibrillation.

The aim of the study was to assess the safety and efficacy of thoracoscopic microwave ablation in treating atrial fibrillation (AF). AF predisposes to embolic complications and may cause heart failure. The treatment of AF is still challenging in spite of the promising results of endocardial radiofrequency approach. The present study is a follow-up study of 22 patients (mean age 45 years, range 21-59) with disabling paroxysmal (n=10) or persistent (n=12) AF who underwent a thoracoscopic microwave isolation of pulmonary veins. The patients had a lone AF. All the patients had suffered from severely disabling AF for >1 year (range 1-16 years) without any response to antiarrhythmic medication. The patients have been followed-up on an average of 11 months (range 3-22 months). During the follow-up, 13 (60%) patients have become asymptomatic without any documentation of AF since at least two months, six (27%) patients with anti-arrhythmic medication have clinically improved. Because of major intrathoracic bleeding and because of liver damage the thoracoscopy wound had to be expanded to open thoracotomy in two patients. Thoracoscopic AF microwave ablation seems to be a promising alternative to endocardial ablation in the treatment of highly symptomatic paroxysmal and persistent AF.

Venous obstruction after pacemaker implantation.

BACKGROUND: Central vein leads are known to predispose to venous obstruction. Although usually asymptomatic, obstruction may render electrode removal difficult. This study aimed at quantifying changes in venous calibers in a prospective fashion by intravenous contrast venography (ICV) before and after pacemaker (PM) or cardioverter-defibrillator implantation. METHODS: One hundred and fifty (mean age 67; 61% male) consecutive patients were enrolled, and followed for 6 months. A successful ICV was done at baseline prior to implantation and at 6-month follow-up in 136 (91%) patients. Minimum (D(min)) and maximum (D(max)) vessel diameters were obtained from both ICVs. A new stenosis was defined as a 50% diameter reduction in a venous segment when compared to baseline. We implanted a total of 230 electrodes: 47 (34.6%) single lead, 84 (61.8%) 2-lead, and 5 (3.7%) 3-lead systems. RESULTS: At baseline ICV, 10 patients (7%) were found to have venous anomalies, including 8 patients with obstructive lesions, 1 patient with a persistent left superior vena cava, and 1 patient with double axillary vein. At 6 months, a new obstructive venous lesion had developed in a total of 19 (14%) patients, none of whom exhibited any local symptoms. Of these patients 14 (10%) had a stenosis (mean D(min) 4.6 mm and diameter 38% of baseline), and 5 (3.6%) had a complete venous occlusion. In most cases the new stenosis developed in a location where the vessel was narrowest at baseline. Clinical predictors for the development of stenosis were atrial fibrillation at baseline and biventricular PM implantation. CONCLUSIONS: This is the first systematic study to quantify venous changes after PM or ICD implantation. Our study shows that venous anomalies rendering PM implantation difficult are not infrequent. The incidence of new venous obstruction was 14%. Atrial fibrillation and biventricular PM implantation were independent predictors of venous obstruction.

Transesophageal echocardiography in the diagnosis of thrombosis associated with permanent transvenous pacemaker electrodes.

OBJECTIVES: We sought to assess the value of transesophageal echocardiography (TEE) in the diagnosis of PM-lead-associated central venous thrombi. BACKGROUND: Venous thrombosis is not infrequent after pacemaker (PM) or implantable cardioverter-defibrillator (ICD) implantation. Previous incidence studies of thrombosis have been based on venography or Doppler ultrasound, but the role of TEE has not been systematically evaluated in this setting. METHODS: Study group comprised 66 consecutive patients (mean age 64 years, 67 % male) referred for implantation of their first PM or ICD and with a successful TEE, transthoracic echocardiography (TTE) and venography at 6 months after implantation. The total number of implanted leads was 110. During the 6 months of clinical follow-up, nuclear ventilation-perfusion scan or spiral computed tomography was performed when symptoms aroused a clinical suspicion of PE. RESULTS: TEE revealed a right atrium (RA) or lower superior vena cava (SVC) thrombus in 6 (9%) patients. These thrombi were not visualized by TTE or venography. Additionally, 12 (20%) patients were found to have venographic subclavian or innominate vein thrombi, but none of those could be diagnosed with TEE. Symptomatic pulmonary embolism (PE) was diagnosed in two and an asymptomatic PE in one individual and two of these occurred among the six patients with a thrombus in TEE. No clinical predictors for thrombosis were found. CONCLUSIONS: TEE is an excellent method to visualize electrodes within the RA and proximal SVC. Electrode-associated RA thrombi appear to be relatively common after PM implantation, and they may remain undetectable by venography or TTE. Although these thrombi are mostly asymptomatic, they can give rise to pulmonary embolism and should also be kept in mind in the differential diagnosis of endocarditis. TEE is the method of choice for the diagnosis of these lesions.

Verification of pacemaker automatic mode switching for the detection of atrial fibrillation and atrial tachycardia with Holter recording.

AIMS: Verification of the accuracy of onset, offset, and duration of automatic mode switching (AMS) of pacemakers compared with onset and end of atrial fibrillation (AF) or atrial tachycardia (AT). Correct pacemaker diagnosis of atrial tachyarrhythmias (AA) is indispensable for reliable automatic prevention and intervention algorithms of AA. METHODS AND RESULTS: Comparison was made of the AMS registration of the pacemaker-stored electrograms (EGMs) and the number and cumulative duration of these episodes with continuous 7-day Holter monitoring. Atrial sensitivity was kept at 0.5 mV and far field R-wave recognition in the atrial channel was excluded by blanking of this signal. Lead types were confined to leads with short-ring tip spacing (10-13.8 mm). During Holter monitoring, 18 of 57 included patients with standard reason for pacemaker implantation showed episodes of AF or AT. Cumulative duration of AF and AT from Holter was correctly interpreted by the pacemaker in 99.9% of the patients. All episodes of AF, as seen on the Holter recording, were recognized by the pacemaker (correlation 99.9%). During AF, multiple episodes of undersensing were detected. The number of AMS episodes was influenced by undersensing during AF. The influence of these short episodes of undersensing on the total duration of AF was trivial (cumulative duration of AF was 99.9% correct). In patients with AT without AF on Holter (n=7) and in contrast to the AF episodes, the cumulative AT duration did not correlate well (63%) with the Holter recordings. The number of AMS episodes in the setting of AT was influenced by the atrial tachycardia detection rate setting and the duration of the post-ventricular atrial blanking interval. CONCLUSION: The total duration of AF is correctly represented by the total duration of AMS and can be considered a reliable measure of total AF duration. AT duration was poorly correlated with AMS duration. The number of mode switches does not reflect the number of episodes of AF/AT. Increased memory capacity allowing the storing of all EGMs triggered by the initiation of AF/AT would be the ideal setting with which to optimize the diagnostic performance of pacemakers.

A technique of lead insertion for low atrial septal pacing.

BACKGROUND: Pacing in the low right atrial septum (LAS) appears superior to right atrial appendage or free wall stimulation for the prevention of paroxysmal atrial fibrillation. However, insertion of active fixation lead in the low right atrial septal position is difficult and time consuming, inhibiting application of this pacing method in daily practice. METHODS: The technique of handling and positioning of a new "over the wire" lead system is presented with emphasis on electrocardiographic P wave pattern and fluoroscopic landmarks. RESULTS: The initial results demonstrate an acute implantation and short-term success of LAS pacing of >90% in the first 100 patients without major complications. Pacing thresholds at 3 and 6 months were fully comparable with that of the conventional atrial pacing, whereas impedance and atrial sensing signals were significantly higher at 3 and 6 months follow-up. CONCLUSION: These favorable initial results justify recommanding chronic LAS pacing with the active fixation atrial lead and providinge guidelines and fluoroscopic landmarks for the implantation. Insertion of the atrial active fixation lead positioned with the Locatortrade mark tool strongly supports the implantation procedure.