Implantable cardioverter defibrillator lead implantation in patients with a persistent left superior vena cava--feasibility, chances, and limitations: representative cases in adults.

AIMS: Device implantation may be challenging in patients with venous abnormalities. The most common congenital variation--frequently associated with other congenital abnormalities--is described as persistent left superior vena cava (PLSVC). METHODS AND RESULTS: The present case series demonstrates successful implantable cardioverter defibrillator (ICD) lead implantation in the most common anatomic variations of PLSVC. All types of current ICD models (single and dual chamber, VDD, and cardiac resynchronization therapy devices) were used. Angiographic findings and implantation techniques (e.g. guiding and diagnostic catheters, wires, occlusion balloons, and rotation sequences) are presented in images and movie sequences. CONCLUSION: Device implantation in patients with PLSVC may be complex but a successful transvenous approach is possible in most of the cases. Careful imaging prior to implantation procedure is essential for understanding the individual anatomy and in order to choose adequate material and implantation strategy.

Pre-hospital discharge testing after implantable cardioverter defibrillator implantation: a measure of safety or out of date? A retrospective analysis of 975 patients.

AIMS: The present study evaluates the relevance and additional safety value of pre-hospital discharge (PHD) testing in patients with implantable cardioverter defibrillator (ICD) therapy. METHODS: From June 1998 to May 2009, 975 patients (830 male, 145 female) with ICD were screened retrospectively for failed PHD and analysed for its consequences, risk factors, and patient characteristics after successful intra-operative testing in the implantation procedure. RESULTS: Pre-hospital discharge testing procedure was performed in 809 cases. No serious adverse events (e.g. death, persistant ventricular fibrillation or ventricular tachycardia, stroke) occurred. The overall incidence of failed PHD was 1.4% (n = 11). The underlying mechanisms were defibrillation threshold failure in 9/11 cases and sensing failure in 2/11 cases. CONCLUSIONS: In this study predictors for PHD-failure are: (i) cardiomyopathy other than ischaemic or dilative, (ii) young age, and (iii) small or very large left ventricular end-diastolic diameter ( < 40 or > 65 mm). Particularly, (i) manufacture of device or leads, (ii) lead design, (iii) medical treatment, or (iv) gender have no significant influence on PHD failure.

Ventricular oversensing in 518 patients with implanted cardiac defibrillators: incidence, complications, and solutions.

The present study evaluates the incidence of various complications in implanted cardiac defibrillators (ICD) therapy due to ventricular oversensing (VO) and its complications. From June 1998 to May 2005, we retrospectively screened 518 patients (1085.6 patient years) for the occurrence of VO episodes (441 male, 77 female). The overall incidence was 7.3% (n = 38) with inappropriate shock deliveries accounting for 2.3% (n = 12). All VO episodes were caused by either T-wave oversensing (n = 10), myopotentials (n = 8), electrode failure (n = 5), interference with electromagnetic fields (n = 3), double-counting (n = 4), pacemaker interactions (n = 2), or others (n = 2). There were five life-threatening events due to inappropriate ICD reaction. In eight (22%) cases, ICD reprogramming was able to avoid further oversensing episodes (e.g. adaptation of sensitivity, T-wave suppression feature), 13 (35%) patients had to undergo invasive procedures (e.g. electrode replacing) to suppress VO, 16 (43%) were told to avoid the trigger situation, and one demanded to deactivate all ICD therapies because of inappropriate shock delivery. Our data demonstrate that VO is a rare complication, but might lead to life-threatening events. In most cases, VO episodes could be prevented by appropriate ICD reprogramming or avoidance of the initiating trigger.

Microwave ablation of an ischemic sustained ventricular tachycardia during aortocoronary bypass, mitral valve and tricuspid valve surgery guided by a three-dimensional non-fluoroscopic mapping system (CARTO).

Postinfarct patients with malignant ventricular tachyarrhythmias (VTs) are prone to an increased risk for sudden cardiac death and implantation of an internal cardioverter-defibrillator (ICD) often is recommended. In cases where the VTs are incessant or refractory to medical treatment, disruption of the macro-reentry circuit, which represents the arrhythmogenic substrate for postinfarct VTs, is a major therapeutical goal for electro-physiologists. The precise identification of this underlying macro-reentrant circuit depends on conventional mapping techniques (i.e. diastolic potentials, entrainment) and more recently by a three-dimensional non-fluoroscopic electro-anatomical mapping system (CARTO), which integrates anatomical and electrophysiological information to reconstruct a three-dimensional activation and propagation map of the relevant VT. This reports describes on a patient with recurrent, drug-refractory, hemodynamically stable monomorphic VTs on the basis of a 2-vessel coronary artery disease, reduced left ventricular ejection fraction, who was scheduled for coronary artery bypass graft operation combined with mitral valve replacement and reconstruction of the tricuspid valve. Preoperatively, the underlying mechanism of the VT was identified by CARTO mapping with a slow conduction zone and a wide exit site at the inferoapico-basal portion of the left ventricle. In close cooperation between the cardiologists and the surgeons the decision for a simultaneous ablation approach during the subsequent operation was made. Successful ablation of the VT using microwave energy was confirmed by non-inducibility of the VT in the perioperative electrophysiologic study. This case report highlights the use of CARTO mapping to identify postinfarct VTs as well as the application of microwave energy as a useful tool to cure postinfarct ventricular arrhythmias.

Long term biventricular resynchronisation therapy in advanced heart failure: effect on neurohormones.

OBJECTIVE: To assess prospectively the effect of cardiac resynchronisation therapy (CRT) on New York Heart Association (NYHA) functional class, cardiac function, cardiopulmonary exercise performance, and neurohormonal activation during 24 months' follow up. DESIGN: Controlled study. PATIENTS AND RESULTS: 124 patients with severe congestive heart failure (ejection fraction < 35%, NYHA III-IV) and left bundle branch block (QRS duration > 150 ms) were enrolled (control group, n = 59; CRT group, n = 65) and followed up at 1, 3, 12, and 24 months. Compared with the control group, CRT led to significant short and long term improvements in functional NYHA functional class (mean (SEM) 2.1 (0.4) v 2.8 (0.4) at 24 months, p < 0.05), mean ejection fraction (25.7 (4)% v 21.1 (5)% at 24 months, p < 0.05), peak Vo(2) (16.8 (3.9) v 12.6 (3.5) ml/kg x min at 24 months, p < 0.01), and Vo(2) at anaerobic threshold (14.4 (3.7) v 10.8 (3.2) ml/kg x min at 24 months, p < 0.05). In addition, CRT for one and 12 months significantly decreased the plasma concentrations of noradrenaline (norepinephrine) and N-terminal fragment of pro-brain natriuretic peptide, whereas no changes were observed for other neurohormones such as antidiuretic hormone, aldosterone, and endothelin. CONCLUSION: Long term CRT (

[Pacemaker therapy of hypertrophic obstructive cardiomyopathy. PIC (Pacing in Cardiomyopathy) Study Group]. / Schrittmacher-Therapie der hypertroph-obstruktiven Kardiomyopathie. PIC-Studiengruppe.

Clinical management of patients with symptoms caused by pharmacological refractory hypertrophic obstructive cardiomyopathy must consider surgical myectomy, percutaneous transluminal septal myocardial ablation and implantation of a DDD pacemaker. Until now, no prospective, double blind, randomized studies have yet been carried out to determine the merits of each of these treatment alternatives. However, uncontrolled studies have shown that short atrioventricular delay dual-chamber pacing reduces outflow tract obstruction. Aim of the study was to investigate the results of the pacemaker therapy in a prospective, double blind randomized crossover procedure. All patients with hypertrophic obstructive cardiomyopathy included in this multicenter study were either refractory or intolerant to drugs and typically had pressure gradients higher than 30 mm Hg. In 83 patients, mean age 53 (18 to 82) years who responded favorably to a temporary pacing test, a DDD pacemaker was implanted. After echo- and echo-Doppler-based measurements of hemodynamic parameters the patients were randomized into 2 groups, those with an implanted pacemaker in the inactivated mode (AAI) and those with a pacemaker in the activated mode (DDD with optimized short AV delay). A crossover of these groups was performed after 12 and 24 weeks, respectively. Both objective parameters of echo including Doppler, and spiroergometry, and subjective parameters of angina, dyspnea, and quality of life were recorded. Additionally, subgroups based on age decades were analyzed. After 12 weeks in the DDD mode, regardless of the randomization sequence, a decrease of the pressure gradient from 59 +/- 36 mm Hg (median) to 30 +/- 25 mm Hg was proven significant (p < 0.001). The endurance of the patients who, during screening, achieved less than 10 minutes of exercise by the Bruce protocol improved by 21% under DDD mode. The main symptoms, as measured by the NYHA classification, improved statistically significant from a mean of 2.4 to 1.7 for functional class, from a mean of 2.4 to 1.4 for dyspnea and from a mean of 1.0 to 0.4 for angina. Subgroup analysis showed improvements depended significantly upon age, with a marked improvement between the ages of 60 and 70, which was statistically significant as compared to other decades. Subjective improvements in the quality-of-life of patients was measured using a specially developed questionnaire. These findings justify, by all means, the intention to implant a DDD pacemaker in older patients. In younger and/or such patients with elevated pressure gradients, the results of ongoing randomized studies comparing myectomy, PTSMA and pacing have to be considered.