Home monitoring of implantable cardioverter-defibrillators: interpretation reliability of the second-generation "IEGM Online" system.

Aims: Intracardiac electrograms (IEGMs) are essential for the assessment of implantable cardioverter-defibrillator (ICD) function. The Biotronik Home Monitoring systems transmit an 'IEGM Online' that is shorter than the full-length programmer IEGM due to technical constrains. The aim of this study was to evaluate the accuracy of the physician's classification of the underlying rhythm based on the second-generation IEGM Online.

Clinical, anatomical, and technical risk factors for postoperative pacemaker or defibrillator lead perforation with particular focus on myocardial thickness.

Background: Postoperative lead perforation is a life-threatening complication of cardiac pacing. Identification of precipitating factors for this serious complication may help to anticipate a specific risk profile and to minimize the incidence.

Methods: We conducted a retrospective tertiary referral center analysis to clarify clinical, anatomical, and technical characteristics related to pacemaker (PM) and cardioverter/defibrillator lead perforation.

Not left ventricular lead position, but the extent of immediate asynchrony reduction predicts long-term response to cardiac resynchronization therapy.

Cardiac resynchronization therapy (CRT) is an effective treatment for a large subgroup of chronic heart failure patients. Various attempts to improve the high non-responder rate of 30 % by preoperative asynchrony assessment have failed. We hypothesized that superior response to CRT is correlated with greater acute reduction of asynchrony and that a concordant left ventricular (LV) lead is beneficial compared to a discordant lead.

Complete atrioventricular block after TAVI: when is pacemaker implantation safe?

Introduction: Atrioventricular (AV) block is a frequent complication of transcatheter aortic valve implantation (TAVI). TAVI is routinely performed under anticoagulation using heparin, which potentially may lead to an increased bleeding rate in patients who undergo permanent pacemaker (PPM) implantation immediately after TAVI. As the number of TAVI procedures continues to rise, data on the optimal management of TAVI-related AV block are needed.

Dyssynchrony parameter-guided interventricular delay programming.

Aims: Interventricular (VV) delay optimization for cardiac resynchronization therapy (CRT) is recommended by current guidelines and several algorithms have been proposed. So far, however, no gold standard has been established in the clinical routine. We hypothesized that dyssynchrony parameter assessment might guide VV delay optimization and investigated whether dyssynchrony parameter changes induced by sequential biventricular pacing follow a predictable pattern.

Pacing-induced cardiomyopathy in patients with right ventricular stimulation for >15 years.

Aims: The prevalence of pacing-induced cardiomyopathy (PiCMP) has been reported to be 9% 1 year after implantation. As long-term data are sparse, the aim of our study was to evaluate the prevalence of PiCMP in a cohort of patients with at least 15 years of right ventricular (RV) pacing.

Methods And Results: Inclusion criteria were RV stimulation for at least 15 years due to atrioventricular block III° and absence of structural heart disease at the time of initial implantation.

Remote monitoring of implantable-cardioverter defibrillators: results from the Reliability of IEGM Online Interpretation (RIONI) study.

Aims: Intracardiac electrograms (IEGMs) recorded by implantable cardioverter-defibrillators (ICDs) are essential for arrhythmia diagnosis and ICD therapy assessment. Short IEGM snapshots showing 3-10 s before arrhythmia detection were added to the Biotronik Home Monitoring system in 2005 as the first-generation IEGM Online. The RIONI study tested the primary hypothesis that experts' ratings regarding the appropriateness of ICD therapy based on IEGM Online and on standard 30 s IEGM differ in <10% of arrhythmia events.

Non-invasive assessment of myocardial contractility from force-frequency relationship in patients with implanted pacemakers: first results.

Aims: In the normal heart, myocardial contractility is augmented at elevated heart rates. This effect is known as force-frequency relationship (FFR). The FFR is altered in failing hearts and may be used to detect myocardial function impairment.

Is antiarrhythmia device implantation safe under dual antiplatelet therapy?

Background: Device implantations in patients on dual antiplatelet-therapy (DA-therapy) continue to rise. The aim of our study was to compile and analyze data on complications of antiarrhythmia device implantation under DA-therapy.

Methods: We prospectively collected data on all device implantations in our department from January 2008 until February 2009.

Implementation of seven echocardiographic parameters of myocardial asynchrony to improve the long-term response rate of cardiac resynchronization therapy (CRT).

Background: Cardiac resynchronization Therapy (CRT) is an effective therapy for chronic heart failure with beneficial hemodynamic effects leading to a reduction of morbidity and mortality. The responder rates, however, are low. There are various and contentious echocardiographic parameters of myocardial asynchrony.

Circumferential 2D-strain imaging for the prediction of long term response to cardiac resynchronization therapy.

Background: Cardiac Resynchronization Therapy (CRT) leads to hemodynamic and clinical improvement in heart failure patients. The established methods to evaluate myocardial asynchrony analyze longitudinal and radial myocardial function. This study evaluates the new method of circumferential 2D-strain imaging in the prediction of the long-term response to CRT.

Should we use the rate-adaptive AV delay in cardiac resynchronization therapy-pacing?

Aims: Recommendations for programming the rate-adaptive AV delay in CRT.

Methods And Results: In cases of continual biventricular pacing, the optimal AV delay in CRT (AVD(opt)) is the net effect of the pacemaker-related interatrial conduction time (IACT), duration of the left-atrial electromechanical action (LA-EAC(long)), and the duration of the left-ventricular latency period (S(V)-EAC(short)). It can be calculated by AVD(opt) = IACT+LA-EAC(long)-S(V)-EAC(short).

Evaluation of longitudinal and radial two-dimensional strain imaging versus Doppler tissue echocardiography in predicting long-term response to cardiac resynchronization therapy.

Introduction: Cardiac resynchronization therapy (CRT) leads to hemodynamic and clinical improvement in patients with heart failure. This study compares the new technique of 2-dimensional (2D) strain imaging with Doppler tissue imaging (DTI) in the prediction of the long-term response to CRT.

Methods: In all, 38 patients with heart failure (New York Heart Association II-III, QRS > 120 milliseconds, left ventricular ejection fraction < 0.

Predictors of chronotropic incompetence in the pacemaker patient population.

Aims: We prospectively evaluated results from cardiopulmonary exercise testing for chronotropic incompetence (CI) in a cohort of 292 pacemaker patients. In addition, we evaluated comorbidity and antiarrhythmic patient data as indicators of CI.

Methods And Results: On the basis of exercise stress testing and application of the definition of CI by Wilkoff, 51% of our cohort was categorized as having CI.

[Echocardiographic evaluation to select patients for cardiac resynchronization therapy].

Wide QRS complex and asynchronous myocardial contraction in heart failure are associated with poor prognosis. Resynchronization can be achieved by biventricular pacing (BVP), which leads to hemodynamic and clinical improvement and reverse remodeling, and may improve survival. However, there is a substantial subset of patients with wide QRS complexes in the electrocardiogram who does not improve despite BVP, and there are findings which suggest that resynchronization therapy may be also beneficial for heart failure patients with normal QRS duration.

Influence of the atrio-ventricular delay optimization on the intra left ventricular delay in Cardiac Resynchronization Therapy.

Background: Cardiac Resynchronization Therapy (CRT) leads to a reduction of left-ventricular dyssynchrony and an acute and sustained hemodynamic improvement in patients with chronic heart failure. Furthermore, an optimized AV-delay leads to an improved myocardial performance in pacemaker patients. The focus of this study is to investigate the acute effect of an optimized AV-delay on parameters of dyssynchrony in CRT patients.

Chronotropic incompetence in patients with an implantable cardioverter defibrillator: prevalence and predicting factors.

Chronotropic incompetence (CI), which has not been systematically examined in the ICD patient population, may have implications for device programming. A total of 123 ICD patients were classified into three groups: single-chamber ICD with sinus rhythm, dual-chamber ICD with sinus rhythm, and single-chamber ICD with permanent atrial fibrillation. Heart rate response, maximum oxygen uptake, and oxygen uptake at the anaerobic threshold were measured during treadmill exercise testing.

Reduction of right ventricular pacing in patients with sinus node dysfunction using an enhanced search AV algorithm.

Background: Dual chamber pacing typically results in a high percentage of ventricular pacing. A number of studies have been conducted suggesting detrimental effects of ventricular desynchronization produced by long-term RV pacing. Pacemaker algorithms that extend the AV interval to uncover intrinsic AV conduction have been utilized to reduce ventricular pacing.

Tissue Doppler echocardiography and biventricular pacing in heart failure: patient selection, procedural guidance, follow-up, quantification of success.

Asynchronous myocardial contraction in heart failure is associated with poor prognosis. Resynchronization can be achieved by biventricular pacing (BVP), which leads to clinical improvement and reverse remodeling. However, there is a substantial subset of patients with wide QRS complexes in the electrocardiogram that does not improve despite BVP.

Autocapture enhancements: unipolar and bipolar lead compatibility and bipolar pacing capability on bipolar leads.

Beat-by-beat Autocapture maximizes device longevity by minimizing stimulus amplitude while assuring patient safety. Currently, Autocapture permits use of only bipolar leads. The authors have devised a detection method that operates with unipolar and bipolar leads and covers all pacing and sensing combinations (but bipolar pace and sense simultaneously).

[Biatrial pacing as an effective therapy method of paroxysmal atrial fibrillation].

For effective management of drug-refractory atrial fibrillation as the most common arrhythmia new methods are needed. In case of existing interatrial conduction disturbance the use of biatrial pacemaker with standard right atrial lead and additive coronary sinus lead for left atrial pacing shows an antiarryhthmic effect due to atrial resynchronisation. In order to demonstrate the antiarrhythmic effect of biatrial pacing, 74 pts.

Electrogram signals recorded from acute and chronic pacemaker implantation sites in pacemaker patients.

Electrogram signals recorded from typical pacemaker implantation sites may be useful for a variety of pacemaker system functions including pacemaker follow-up, atrial and ventricular sensing (event detection), and triggered electrogram storage. We quantified the electrical characteristics of pacemaker pocket electrograms using a subcutaneous electrode array (SEA) in a population of 48 patients undergoing initial or replacement pacemaker implantation. SEA recorded intrinsic R wave amplitudes measured peak to peak averaged 118 microV and 65 microV for the two recorded SEA electrograms and were significantly different (P < 0.

[Non-medicinal therapy tachycardiac arrhythmias].

The conservative antiarrhythmic treatment was improved by the introduction of the Holter-ECG technique, of the serial electrophysiological testing and by new antiarrhythmic drugs. An essential enhancement of the therapeutic possibilities, particularly when ineffectiveness, proarrhythmic action or intolerance of the medicaments are existing, are increasingly the non-medicamentous techniques of the antiarrhythmic therapy. Thus the treatment of arrhythmia has become by far more effective, but at the same time also more complicated and more expensive.

Increased pacing threshold after an automatic defibrillator shock in dogs: effects of class I and class II antiarrhythmic drugs.

A high energy shock delivered by an automatic defibrillator may interfere with pacemaker function. To provide insight into the changes that occur in the threshold for ventricular pacing after the shock from an automatic defibrillator, we measured the time to capture during asynchronous ventricular pacing in dogs from endocardial or epicardial sites, after a 30 joule shock was delivered via conventional automatic defibrillator (AICD) patch electrodes. After a 30 joule shock, there was a transient loss of ventricular capture.