Group purchasing organizations: optimizing cardiac device selection, therapy delivery, and fiscal responsibility.

Group purchasing organizations (GPOs) have played a major role in supporting health care delivery in recent years as the healthcare industry has faced stronger economic pressures. Consequently, a position statement was drafted to act as a guideline for a GPO in creating a fiscally responsible, yet unrestricted environment for physicians to select the most appropriate cardiac device for their patients. This cardiac device selection guideline is to be implemented in hundreds of member hospitals but may be of use in non-member hospitals as well.

Electromagnetic interference in cardiac rhythm management devices.

Clinicians caring for cardiac device patients with implanted pacemakers or cardioverter defibrillators (ICDs) are frequently asked questions by their patients concerning electromagnetic interference (EMI) sources and the devices. EMI may be radiated or conducted and may be present in many different forms including (but not limited to) radiofrequency waves, microwaves, ionizing radiation, acoustic radiation, static and pulsed magnetic fields, and electric currents. Manufacturers have done an exemplary job of interference protection with device features such as titanium casing, signal filtering, interference rejection circuits, feedthrough capacitors, noise reversion function, and programmable parameters.

No output or runaway?

A 75-year-old male was implanted with a Telectronics Meta DDDR model 1250 pacemaker 47 months ago. The patient was evaluated in-office for symptomatic complaints of dizziness, palpitations, and "too slow or too fast" pulse rates. Upon examination, the device displayed sudden no output manifestations for which the device had been recalled.

Activation times for "emergency backup" programs.

A bench study was performed on 42 different pulse generators (PGs) to evaluate the time required to actuate and "emergency backup" (EBU) program. PGs were programmed to loss of capture before the EBU programming key was activated. Activation times for the EBU pause were measured on an ECG strip from the first noncaptured beat to the first recaptured beat while the total pause was measured between the two captured beats.

Multicenter experience with a bipolar tined polyurethane ventricular lead.

A multicenter study was undertaken to determine the failure rate of a specific bipolar tined polyurethane ventricular pacing lead, the Medtronic 4004/4004M pacing lead. Seven centers in the United States and Canada implanted 586 Medtronic 4004/4004M pacing leads. The study was designed to determine the probability and clinical manifestations of lead failure.

A verified report of spurious programming: a case study.

A case of unintentional misprogramming is described in which a DDDR pacemaker, programmed to the VVIR mode, reverted to the originally programmed parameters and mode. The misprogramming requires that a particular sequence of steps be followed and has been verified by the manufacturer. This misprogramming may be clinically significant and can be reproduced in an entire family of current pacemakers based on the same software platform.

Analysis of the effectiveness of in-office and transtelephonic follow-up in terms of pacemaker system complications.

A study was undertaken to determine the most effective method of pacemaker follow-up in terms of the total number of complications detected and yield per follow-up in single and dual chamber pacing systems. The analysis involved 9,786 patient records from 635 patients. The records were reviewed with respect to method of follow-up, number of chambers paced, and complications detected.

Performance of a 3.2-mm to 6-mm adaptor.

A study was undertaken to evaluate the performance of a 366-08 adaptor that adapts an in-line bipolar 3.2-mm connector to a 6-mm pulse generator connector. A total of 14 adaptors were implanted in individual patients.

Evaluation of an in-line bipolar polyurethane ventricular pacing lead.

A study was undertaken to evaluate the performance of the Medtronic 4012 polyurethane in-line bipolar pacing electrode. One hundred twenty six patients implanted with the 4012 lead were followed by our clinic with 116 of these leads implanted at our institution. Patients were followed a minimum of every 4 months.

A multicenter experience with a bipolar tined polyurethane ventricular lead.

A multicenter study was undertaken to determine the failure rate of a specific polyurethane bipolar tined pacing lead, the Medtronic 4012 pacing lead. Six centers in the United States and Canada implanted 1,190 Medtronic 4012 pacing leads. The study was designed to determine the probability and clinical manifestations of lead failure.

Activation times for "emergency back-up" programs.

A bench study was performed on 34 different pulse generators to evaluate the time necessary to actuate an "emergency back-up" (EBU) program. Pacemakers were programmed to loss of capture before the EBU was activated. Two pauses were measured that included the total pause from captured beat to captured beat and the time from the first pacing artifact showing loss of capture to the first captured beat resulting from EBU activation.

Comparison of low rate dual chamber pacing to activity responsive rate variable ventricular pacing.

A study was undertaken to evaluate exercise performance in 18 dual chamber pacemaker patients believed to be chronotropically incompetent. All patients were paced in a DDD AV synchronous mode at 80 beats per minute (beats/min) as well as an externally triggered, activity responsive VVIR mode. Patients underwent two single blind, randomized symptom-limited treadmill tests (Sheffield protocol).

An advanced data base pacemaker follow-up system that's customizable.

In an effort to deal with the volumes of information gathered from pacemaker follow-up, the obvious need for a computerized data base was realized. In order to meet specific goals and needs, an advanced relational data base program was custom designed for pacemaker follow-up. The program has the ability to store and report all follow-up data throughout the life of each patient on a relatively few page report.

Crosstalk during bipolar pacing.

Bipolar sensing pulse generators were thought to have eliminated crosstalk problems evident in unipolar systems. Crosstalk has been observed in the Model 284-02 bipolar sensing pacemakers. These intermittent problems were resolved by decreasing atrial output, decreasing ventricular sensitivity or increasing the ventricular blanking period.