"Floating" catheter for temporary transvenous ventricular pacing

Pacemaker therapy

This article reviews the indications for pacemaker implantation and the techniques and devices currently in use. The management of patients who require permanent pacemakers and the potential complications involved are discussed. The article concludes with a brief synopsis of temporary pacing.

The use of the balloon-tipped floating catheter in temporary transvenous cardiac pacing

The effectiveness and safety of balloon-tipped, flow guided, electrodes for ventricular pacing as opposed to the fluoroscopy-guided semi-rigid bipolar electrodes have never been compared in a controlled study. A prospective study was therefore undertaken to compare both techniques in semi-elective and emergency procedures. Flow guided electrodes were inserted in 67 patients (group A) and semi-rigid electrodes in 44 patients (group B). The results of group A were judged to be superior to those of group B in four aspects: a) shorter time (6'45" vs. 13'30", p less than 0.0005); b) lower incidence of catheter displacement (13.4 vs. 32.0 percent, p less than 0.05); c) longer interval of time between implantation and catheter displacement (4.4 vs. 1.9 days, p less than 0.0005); d) lower incidence of serious ventricular arrhythmias during insertion (1.5 vs. 20.4 percent, p less than 0.005). Threshold at insertion was not significantly different (0.6 +/- 0.3 vs 0.7 +/- 0.2 milliampere). The superiority of flow-guided electrodes over fluoroscopy-guided electrodes persisted in the comparison of semielective insertions in groups A and B. We conclude that the flow-guided insertion technique is safer, more expeditious and more stable than the fluoroscopy-guided technique in semi-elective as well as in emergency insertions.

Unipolar ventricular electrogram in the diagnosis of right ventricular ischemic injury

Unipolar ventricular electrograms were recorded in the right ventricular apical area in five patients with clinical, hemodynamic features of the right ventricular infarction. The intracavitary potential exhibited a downward displacement of the ST segment (1.5 mV). This significant negative current of injury in the ventricular electrogram is consistent with ischemic injury of the free right ventricular wall in the area subtended by the intracavitary exploring electrode. We suggest that ventricular electrographic recordings be performed in patients who present with acute inferior wall infarction requiring temporary electrode catheter pacing for serious AV conduction disturbances. The presence of a significant downward ST segment displacement (1.5 mV) provides further support and an electrical criterion for right ventricular ischemic injury.

Bedside emergency transvenous cardiac pacing: experience in two community hospitals

Emergency bedside transvenous subclavian cardiac pacing in 51 patients over a three-year period in two community hospitals is described. Fifty-three procedures were performed at the bedside with semifloating bipolar pacemaker catheters under continuous electrocardiographic monitoring to assist in the placement of the catheter tip. Of the 53 procedures, initial success in pacing was observed in 41 patients (77%). The largest number of failures to either initiate or maintain pacing was observed in the group with cardiac arrest associated with extensive myocardial infarction and complete heart block. Complications of this procedure were minimal. Only one 10% pneumothorax was noted. This modified technique is easily mastered and may prove lifesaving in an emergency.

A balloon tipped catheter for obtaining his bundle electrograms without fluoroscopy

A technique for recording His bundle activity in man without fluoroscopic guidance is described. Balloon tipped tri- or tetrapolar catheters were designed with pacing electrodes located at the catheter tip, and two fine sensing electrodes 4 and 5 cm behind it. The catheter tip was preformed into a "J" curve. Following percutaneous transfemoral insertion, the catheter is floated to the right ventricle under electrocardiographic control. This tip configuration and the transfemoral route of insertion typically directs the catheter into an inverted "J" position with its tip in or near the right ventricular apex. Subsequent catheter withdrawal carries the sensing electrodes through the superior portion of the tricuspid valve and permits recording from the His bundle. With this technique His bundle recordings were possible in 23 of 24 patients. Re-advancement into the right ventricular apex permits stable temporary pacing.