Rate-adaptive cardiac pacing: cost versus technology versus patient benefit

Pacemakers

Rapid advances in pacing technology will continue to affect the quality of life of many patients with cardiovascular disease. A truly "smart" device that seemed fanciful 30 years ago now seems to be a virtual certainty by early in the next century. The surgical contributions and expertise of individuals trained in cardiothoracic surgery in these bradypacing developments is highly desirable to minimize morbidity to the greatest possible degree, to optimize the outcome of the procedure for the individual patient, and to conserve health care costs as much as possible. To maintain this cardiothoracic presence in cardiac pacing, acquisition of knowledge and expertise in the basic electrophysiology and technology of cardiac pacing, to go along with surgical expertise, is necessary on the part of individuals with the interest and opportunity to do so.

Benefits and limitations of rate adaptive pacing under laboratory and daily life conditions in patients with minute ventilation single chamber pacemakers

Rate adaptive pacing has been shown to improve hemodynamic performance and exercise tolerance during acute testing. However, there remain concerns about its benefit in daily life and possible complications incurred by unnecessary pacing. This double-blind crossover study compared the benefit of rate adaptive (SSIR) versus fixed rate (SSI) pacing under laboratory and daily life conditions in 20 rate incompetent patients with minute ventilation single chamber pacemakers (META II). The heart rate (HR) response during three different exercise tests (treadmill, bicycle ergometry, walking test) was correlated with the Holter findings during daily life in either pacing mode. The maximal HR was significantly higher in the SSIR-mode compared to the SSI-mode, both during laboratory testing (treadmill: 123 +/- 15 vs 93 +/- 29 beats/min; ergometry: 118 +/- 15 vs 89 +/- 27 beats/min; walking test: 127 +/- 9 vs 95 +/- 26 beats/min, all P values < 0.01) as well as during daily life (Holter: 126 +/- 13 vs 103 +/- 24 beats/min, P < 0.01). On Holter, the average HR (71 +/- 14 vs 71 +/- 8 beats/min) and the percentage of paced rhythm (54% vs 62%, SSI- vs SSIR-mode, P = NS) were not different in either mode. However, despite a 30% rate gain in the SSIR-mode, the exercise capacity remained unchanged, and only 38% of patients preferred the SSIR-mode. Minute ventilation pacemakers provide a physiological rate response to exercise. Irrespective of the protocol used, the findings of laboratory testing are comparable to those during daily life. However, patient selection for rate adaptive single chamber pacing should be made with caution, since the objective benefit of restoring normal chronotropy may subjectively be negligible for most patients.

The additional hospital costs generated in the management of complications of pacemaker and defibrillator implantations

The rapid approach of capitated reimbursement mandates that providers examine their practice patterns associated with all surgical procedures. Documentation of (1) the complications associated with these procedures and (2) the additional hospital costs associated with the management of these complications is critical for comprehensive fiscal accountability. This study analyzed (1) the feasibility of obtaining accurate hospital cost data specific for complications and (2) the outcome in terms of fully loaded hospital costs generated in the management of the most common surgical complications associated with pacemaker and nonthoracotomy implantable defibrillator therapies. Between July 1989 and September 1994, a total of 1031 pacemaker and 105 implantable defibrillator procedures were performed by a cardiac surgeon in a tertiary-level teaching hospital setting. The additional fully loaded hospital costs were determined by (1) correlating clinical data from the complete medical record with complete hospital charge data for the admission(s) related to the complication, (2) carving out complication-related charges based on the clinical data, (3) converting complication-related charges to fully loaded costs based on conversion factors in effect at the time of service, and (4) correlating cost with hospital net reimbursement and payor source. The feasibility study determined that accurate and reliable cost data specific to complications can be obtained, although the process was cumbersome and difficult. The outcomes study determined that mean fully loaded complication costs were $4345 +/- $1540 for pacemaker lead revision and $4879 +/- $3167 for implantable defibrillator lead dislodgement, $24,459 +/- $14,585 for pacemaker infection, and $13,736 +/- $12,505 for defibrillator generator system malfunction. The one infected defibrillator cost $57,213 to treat. Costs exceeded reimbursement for almost all Medicare patients with complications in this study, suggesting that similar shortfalls would occur under a capitation scheme. This information is critical to a complete understanding of the financial impact of interventional procedures in a capitated reimbursement environment.

Safety of pacemaker implantation in patients with transvenous (nonthoracotomy) implantable cardioverter defibrillators

While several reports have documented the safety of implantation of transvenous pacemakers in patients with epicardial patch-based implantable cardioverter defibrillators (ICDs), the implantation of transvenous pacemakers in patients with transvenous (nonthoracotomy) ICDs has not been well-described. We present three patients with transvenous ICDs who subsequently underwent implantation of transvenous pacemakers without complication. Technical considerations and a testing, protocol for detection of pacemaker-ICD interactions are discussed.

Permanent cardiac pacemakers in the elderly

OBJECTIVE

To review (1) Changes in cardiac impulse generation, conduction, and ventricular filling in normal aging and disease; (2) Pacemaker technology and nomenclature; (3) Expert guidelines about pacemaker use; (4) Studies of pacemaker effectiveness and utilization.

DESIGN

Articles were identified through a Medline search, review of articles' bibliographies, and contact with pacemaker manufacturer representatives for information on device features and costs. These articles were reviewed, and the relevant data are presented.

RESULTS

Abnormalities in impulse generation and conduction are common in the elderly. Pacemaker use is higher in the elderly than in other population groups. Hemodynamic changes associated with aging include an increased contribution of atrial contraction to ventricular filling. Pacemakers, which maintain the synchrony between the atria and ventricles, may be particularly advantageous in the elderly for this reason. Rate-responsive ventricular pacemakers improve the quality of life compared with fixed rate devices in some patients over the age of 75. Dual-chamber, sequential pacemakers are more likely to reduce symptoms of pacemaker syndrome than ventricular pacemakers and probably also prolong survival and reduce risk of atrial fibrillation in certain groups of patients. However, dual chamber devices are more expensive and require more frequent follow-up. Pacemaker utilization can vary widely by region. Decisions about pacemakers require explicit tradeoffs between risk and quality of life on one hand and cost on the other. In many clinical situations, there is controversy as to whether pacemakers should be used.

CONCLUSIONS

Pacemakers provide definite benefits to some patients, whereas in others, the likelihood of benefit is uncertain. More sophisticated devices may provide some additional benefit, but they are more costly. Further data is still required to define precisely which groups of patients substantially benefit from complex and expensive pacing modalities compared with simpler ones.

Should surgeons still be implanting pacemakers?

Cardiac pacing has undergone major changes in the areas of manpower, technology, and cost over the past 10 years. Arguments have been made to eliminate cardiac surgical involvement in pacing on the basis of these three areas of change: implantations are increasingly performed by nonsurgeons, surgeons have not kept up with the technologic advances in pacing, and consolidation of bradypacing resources is necessary during a time when reimbursement has declined significantly. This study examined two eras of pacing therapy at an institution where pacemaker implantation has always been performed by cardiothoracic surgeons. The purpose of the study was to critically analyze (1) the current role (if any) of cardiothoracic surgeons in delivery of pacemaker therapy and (2) the current results of cardiothoracic surgical involvement in pacemaker implantation. In 1,562 procedures performed between 1986 and 1992, the infection rate was 0.51% and the overall complication rate (both short-term and long-term) was 5.2%. During era 1 (1/1/86 to 6/30/89), 80% of implants were single-chamber and follow-up was incomplete and dependent in many instances on the referring cardiologist/internist. For the implantations performed in the second era (7/1/89 to 12/31/92) as part of an established Pacemaker Service, complete clinical and transtelephonic follow-up services were provided by this coordinated medical-surgical approach. During era 2, 53.9% of implants were dual-chamber (79% during 1992). Total and infectious complication rates remained low in era 2 despite this change in technology.(ABSTRACT TRUNCATED AT 250 WORDS)