Use of temporary pacemakers during coronary angioplasty: an evolving experience with ventricular fibrillation in 400 cases

Mechanisms of ventricular fibrillation during coronary angioplasty: increased incidence for the small orifice caliber of the right coronary artery

BACKGROUND

Ventricular fibrillation (VF) is not an infrequent complication of percutaneous transluminal coronary angioplasty (PTCA). However, it is not clear why there is a marked discrepancy in the higher incidence of VF during right coronary artery (RCA) approach.

METHODS AND RESULTS

We analyzed in detail every case of VF occurring in 905 consecutive PTCA procedures to investigate possible mechanisms. Sixteen patients (M/F=15/1, mean age: 71 +/- 8 years) with VF during PTCA for the RCA as Group I. Those 51 patients (M/F=48/3, mean age: 70 +/- 9 years) without VF during PTCA for the RCA engagement were designated as Group II. Patients were equipped with cardiac event recorder (CardioCall, Reynolds Medical, UK) before the PTCA, and we set the time period 1 min before and after the event. The lead II was selected to check the QRS width, QTc interval, ST segment change and RR interval before and after event. A total of 905 PTCA procedures were included. There were 561 procedures for the left coronary artery and three events (0.5%) with spontaneous VF. However, there were 16 events (4.6%) of VF during 344 PTCA procedures for the right coronary artery. The incidence of VF for the right side PTCA was significantly higher than for the left side. The orifice of RCA in Group I was smaller than Group II (orifice of RCA in Group I vs. Group II - 2.7+/-0.8 vs. 4.1+/-1.2 mm, P<0.001). Most cases (68.7%) presented with ST segment depression before the onset of VF.

CONCLUSION

A small caliber of RCA and associated ST segment changes played important roles in the patients with VF during the PTCA.

Successful coronary pace-termination of ventricular tachycardia during coronary angioplasty

Coronary pacing has been performed to treat bradycardias occurring during percutaneous transluminal coronary angioplasty (PTCA) using an angioplasty guidewire. We describe a case of a 62-year-old man who developed ventricular tachycardia (VT) during PTCA. The tachycardia was successfully terminated by overdrive pacing via an angioplasty guidewire.

Coronary and left ventricular pacing as standby in invasive cardiology

Coronary pacing using as unipolar negative electrode a guidewire placed in a coronary branch was tested in 349 sites of 300 consecutive patients undergoing coronary angioplasty. It was possible for 339 sites (97%). The threshold currents ranged from 1 to 15 (mean +/- standard deviation 3.4 +/- 2.4) mA. Side effects were seen in 13 patients (4%): 6 (2%) had transient coronary spasm, 4 (1%) had diaphragmatic stimulation, and 3 (1%) had stinging pain at the skin electrode. Of the 10 cases with pacing failure, left ventricular pacing was successfully tested in 5 by introducing the coronary wire or another wire into the left ventricle. It yielded a threshold of 2-8 (3.2 +/- 2.7) mA. Therapeutic pacing for significant bradycardia was required in 7 patients (2%). It was successful in all. Coronary or left ventricular pacing appears to be a simple and reliable temporary measure. When there is no wire in the coronary artery or for diagnostic catheterization, left ventricular pacing can be done using the same setup and any type of guidewire.

Percutaneous transluminal coronary angioplasty: a review of current balloon dilatation systems

The interventional cardiologist is faced with an expanding armamentarium for performing percutaneous transluminal coronary angioplasty (PTCA). Because of rapid advances in technology, new devices are produced on a regular basis, making it difficult to maintain a working knowledge of what is available. Although several excellent textbooks about PTCA have been written, descriptions of available equipment are usually obsolete by the time publication occurs. In order to provide succinct specifications of equipment, we have documented data on balloon catheters, guiding catheters, and guidewires. This information may be useful in the selection of appropriate equipment for PTCA procedures. In addition, the publication of such data in a monthly periodical may provide a more current overview of equipment; information may be occasionally updated as new equipment is released.