Deactivation of a demand pacemaker by transurethral electrocautery. Wajszczuk WJ,
Mowry FM, Dugan NL. The New England journal of medicine. 1969 Jan; 280(1):34-5.
Journal code: 0255562. ISSN: 0028-4793. L-ISSN: 0028-4793. http://chemport.cas.org/cgi-bin/sdcgi?APP=ftslink&action=reflink&origin=springer&version=1.0&coi=
1%3ASTN%3A280%3ADyaF1M%252FktVGjsw%253D%253D&md5=c8ba02e6b084a27f393aa7788cf3ae7c

Electromechanical suppression of a demand pacemaker associated with electrode perforation. Rubenfire M, Timmis H, Freed P, Evangelista JL, Ginsberg H, Wajszczuk WJ.Journal of electrocardiology. 1973; 6(4):367-71. http://www.labmeeting.com/paper/14345524/rubenfire-1973-electromechanical-suppression-of-a-demand-pacemaker-associated-with-electrode-perforation

Implication of a persistent left superior vena cava in transvenous pacemaker therapy and cardiac hemodynamic monitoring. Rubenfire M, Evangelista J, Wajszczuk WJ, Kantrowitz A. Chest. 1974 Feb; 65(2):145-7.

http://chestjournal.chestpubs.org/content/65/2/145.long
An anomalous persistent left superior vena cava may complicate the insertion of transvenous pacemaker electrode catheters as well as the catheterization of the pulmonary artery. It is important to recognize the anomaly because of the ease of confusing the position of the catheters passing through the coronary sinus into a distal coronary vein rather than the right ventricular apex. If the condition is known and is associated with a patent right superior vena cava, a catheter or electrode should probably be passed from the right side. If this is not possible, our experience indicates that the flow-directed balloon-tipped catheter (Swan-Ganz) can be passed easily without fluoroscopic control through an anomalous left superior vena cava to the pulmonary artery. Using a similar balloon-tipped flow-directed pacemaker electrode may be helpful in its positioning in the apex of the right ventricle.

While short-term temporary pacing via the coronary sinus is probably acceptable, placement of a permanent electrode in the coronary sinus is dangerous. If there is congenital absence of the right superior vena cava, an epicardial electrode is likely preferred.

Analysis of pacemaker pulse-wave shape. Basic principles and simulated study of  malfunction. Waldemar J. Wajszczuk and Joseph K. Cywinski. Bulletin, Sinai Hospital of  Detroit. Vol. 23, No 1, January 1975.  

Summary and Conclusion

Recent rapid growth of a network of the Pacemaker Follow-up Clinics created a demand for development of the diagnostic criteria to improve the differentiation between their continuing normal function and their potential malfunctions, either related to age (battery depletion) and to other early malfunction. This experimental study was designed to evaluate the importance of oscilloscopic analysis of the pacemaker pulse-wave shape in follow-up of performance of the im­planted pacemaker and in evaluation of the causes of its malfunction or failure. Spe­cially constructed artificial test loads pro­vided the possibility of reproducing a vari­ety of abnormal clinical conditions which included changes in resistance and capaci­tance of the pacemaker-electrode-myocardium circuit. Differentiation was made between clinical conditions as­sociated with penetration of the interstitial fluid and situations with damage of the elec­trodes but without penetration of the fluid.

The examples of pacemaker pulse-wave shapes presented in this paper were obtained using a Medtronic pacemaker, Type 5870. Elements of evaluation included mea­surements of pulse duration, pulse period (pacemaker repetition rate), and amplitudes of the leading edge (LE) and trailing edge (TE) of the pacemaker pulse-wave shape. Calculations of the LE/TE and TE/LE ratio proved extremely important and valuable. This ratio allowed differentiation between:

A. Malfunction of the pacemaker system due to increased resistance (broken elec­trode, "exit block," etc.) and the depletion of the batteries;

B. Increased resistance without and with penetration of the intersti­tial fluid (damage of the insulation causing changes in the capacitance).

1. Gradual increases of resistance caused disproportionate decrease of the amplitudes of LE and TE and produced marked gradual decrease of the LE/TE ratio.
2. Increased capacitance affected primarily the ampli­tude of the TE out of proportion to that of the LE and resulted in a sudden and marked change in the LE/TE ratio.
3. De­crease of the battery voltage did not affect the LE/TE ratio to a significant degree. These findings proved to be helpful in dif­ferentiating between premature failure or malfunction of the pacemaker system due to battery depletion and that due to other causes such as breakage of the electrode or "exit block."

The importance of the pacemaker pulse-wave shape evaluation in differentia­tion of the causes of its malfunction or fail­ure was well documented. The provided series of pacemaker pulse-wave shapes can be used as guidelines in evaluating the performance of the pacemaker.

Abstracts and Presentations:

1. Simulated diagnostic patterns of artificial cardiac pacemaker failure; experimental study. Presented at the Fifth Annual Meeting of the Association for the Advancement of Medical Instrumentation, Boston, Massachusetts, March 23-25, 1970

2. Importance of oscilloscopic analysis of pacemaker pulse waveshape in pacemaker follow-up. (Abstract). Wajszczuk, Waldemar J. and Joseph K. Cywinski, Medical Instrumentation 7: 83, 1973