Ventricular Tachycardia/Ventricular Fibrillation Ablation in the Setting of Ischemic Heart Disease

Recurrent ventricular tachycardia (VT) in the setting of coronary artery disease is frequently a life-threatening electrophysiologic emergency. Even in patients with an implantable defibrillator, recurrent VT is frequently accompanied by repeated and disabling shock therapy. Catheter ablative therapy offers the ability to provide immediate control of recurrent VT. Long-term elimination of VT should be anticipated in most patients. This article reviews the strategies, tools, techniques, and expected outcome for catheter ablation of stable and unstable ventricular arrhythmias in the setting ischemic heart disease.     

Zinc and Vitamin A in Liver of Foetuses and Infants

ABSTRACT. The association of zinc and vitamin A levels was studied in liver of foetuses and infants which were stillborn or died of various causes between the age of 26 weeks of gestation up to 16 weeks post-partum. No correlation between zinc and vitamin A was observed ( r =0.07). Although smaller infants had more hepatic vitamin A than larger infants no significant difference was observed between these groups for liver zinc values.     

Cardioverter Discharges Following Sensing of Electrical Artifact Due to Fluid Penetration in the Connector Port

We report a unique case of fluid penetration, 3 months after implantation, in the connector port of an automatic implantable Cardioverter defibrillator (ICD) with transvenous subcutaneous lead system. The patient had coronary artery disease and recurrent episodes of ventricular fibrillation, the fluid caused electrical signals interpreted as ventricular fibrillation by the device, which triggered shock delivery .     

Influence of Age, Lead Axis, Frequency of Arrhythmic Episodes, and Atrial Dimensions on P Wave Triggered SAECG in Patients with Lone Paroxysmal Atrial Fibrillation

Signal-averaged P wave of 42 patients with lone paroxysmal atrial fibrillation (PAF) and 29 normal subjects (N) were recorded, using three orthogonal leads and analyzed in the time and frequency (entire P wave or a 100-ms segment ranging from 75 ms before to 25 ms after the end of P wave) domains. PAFs were divided into a group of 12 having ≥ 2 attacks a month (HF) and a group of 30 having ≤ 2 attacks a year (LF). Statistically significant differences were absent with regard to ages of PAF and N; ages of HF, LF, and N at the time of signal-averaged ECG; ages of HF and LF at the time of the first arrhythmic episode; and elapsed times from the first episode. Length of P wave and some frequency-domain parameters were found to be significantly correlated with age. PAF showed a significantly longer duration of P wave in the frontal plane using the time-domain analysis. Frequency analysis was found to be useful in evaluating the influence of attack frequency. HF showed significantly higher values of some frequency-domain parameters than LF and N, while the three groups did not differ for time-domain analysis. P wave duration and frequency content of the three orthogonal leads proved to be significantly different in PAF and N. Right and left atrial echocardiographic dimensions proved to be higher (even if within normal limits) in HF than in LF and N. Results suggest that frequency analysis should be performed on the entire P wave.     

Breast-milk Jaundice

The syndrome of breast-milk jaundice, which often results in cessation of breastfeeding, maternal anxiety, and guilt, may be increasing. Research to date on pregnanediol, increased lipase, and free fatty acids as the causes of breast milk jaundice is reviewed. Variations in current treatment are presented and nursing measures supportive of parents and continued breastfeeding are provided.     

Do European GSM Mobile Cellular Phones Pose a Potential Risk to Pacemaker Patients?

BARBARO, V., et al .: Do European GSM Mobile Cellular Phones Pose a Potential Risk to Pacemaker Patients? A series of in vivo trials were carried out in order to verify whether the electromagnetic field radiated by GSM (Groupe Systemes Mobiles) mobile cellular phones might affect implanted pacemakers. Two European GSM phones of 2-watt power were tested and trials conducted on 101 pacemaker implanted outpatients attending day hospital for routine check-up, who volunteered for trials. Forty-three pacemaker models from 11 manufacturers were tested in all. When the sensing threshold of the pacemakers was set at a minimum and the antenna of the phone was in direct contact with the patient's chest, interference was detected for 26 implanted pacemakers. Specifically, pulse inhibition in 10 of 101 cases, ventricular triggering in 9 of 46 DDD-VDD pacemakers, and asynchronous pacing in 4 of 52 devices. Pulse inhibition was also observed combined with asynchronous pacing in 1 of 52 cases and with ventricular triggering in 2 of 46 cases. Minimum effect duration was ca. 3 seconds but in 6 cases effects continued as long as the interfering GSM signal was on. No permanent malfunctioning or changes in the programmed parameters were detected. Whenever interference was detected, trials were repeated to determine the maximum sensing threshold at which interference persisted (with the antenna in contact with the skin over the pacemaker). Then maximum distance between antenna and pacemaker at which interference occurred was determined at pacemaker maximum and minimum sensing threshold. Under our experimental conditions electromagnetic interference effects were detected at a maximum distance of 10 cm with the pacemaker programmed at its minimum sensing threshold. When the phone antenna was in direct contact with patient's skin over the implant, electromagnetic interference effects occurred at maximum ventricular and atrial sensing thresholds of 4 mV and 2.5 mV, respectively.     

Impact of Systematic Isolation of Superior Vena Cava in Addition to Pulmonary Vein Antrum Isolation on the Outcome of Paroxysmal, Persistent, and Permanent Atrial Fibrillation Ablation: Results from a Randomized Study

Impact of the Systematic Isolation of the Superior Vena Cava.   Background: Pulmonary veins (PVs) have been shown to represent the most frequent sites of ectopic beats initiating paroxysmal atrial fibrillation (AF). However, additional non-PV triggers, arising from different areas, have been reported as well. One of the most common non-PV sites described is the superior vena cava.
Aims: The purpose of the study was to investigate the impact resulting from the systematic isolation of the superior vena cava (SVCI) in addition to pulmonary vein antrum isolation (PVAI) on the outcome of paroxysmal, persistent, and permanent AF ablation.
Methods: A total of 320 consecutive patients who had been referred to our center in order to undergo a first attempt of AF ablation were randomized into 2 groups. Group I (160 patients) underwent PVAI only; Group II (160 patients) underwent PVAI and SVCI.
Results: AF was paroxysmal in 134 (46%), persistent in 75 (23%), and permanent in 111 (31%) of said patients. SVCI was performed on 134 of the 160 patients (84%) in Group II. SVC isolation was not performed on the remaining 26 patients either because of phrenic nerve capture or the lack of SVC potentials. Comparison of the outcome data between the 2 groups, after a follow-up of 12 months, revealed a significant difference in total procedural success solely with patients manifesting paroxysmal atrial fibrillation (56/73 [77%] Group I vs. 55/61 [90%] Group II; P = 0.04; OR 2.78).
Conclusions: In our study, the strategy of the empiric SVCI in addition to PVAI has improved the outcome of AF ablation solely in patients manifesting paroxysmal AF. (J Cardiovasc Electrophysiol, Vol. 21, pp. 1–5, January 2010)