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Biomedical subjects

R G Hauser

Publications and source records attributed to R G Hauser.

46 records · Page 3Linked to original sources
PubMed1981

After-potential oversensing by a programmable pulse generator.

Oversensing and recycling due to a pacemaker stimulus after-potentials are recognized complications of non-competitive pacing. Often masquerading as T-wave sensing, after-potential oversensing may result in slowing or acceleration of pacing rate. We report two cases of after-potential oversensing in patients with R-wave inhibited (VVI) programmable pulse generators. In both cases, recycling of the pulse generators by the sensed after-potentials resulted in slowing of the pacing rates. This phenomenon was abolished non-invasively by decreasing the duration or width of the stimulus pulse which diminished the magnitude of the after-potential signal.

Adult↗
PubMed1981

Limitations of pacemaker system analyzers for the evaluation of implantable pulse generators.

A variety of commercial pacemaker system analyzers have been used to evaluate the electrical performance of pulse generators prior to implant or at the time of reoperation for pacemaker malfunction. We evaluated the ability of seven commercially available pacemaker system analyzers to provide the data required to determine if a given pulse generator was operating according to its manufacturer's specifications. While all pacemaker system analyzers provided accurate data for rate and pulse duration, values displayed for amplitude and sensitivity were inconsistent due to the methods each pacemaker system analyzer employed to measure these parameters. Overall, 22% of representative test sequences yielded data which would have resulted in the inappropriate rejection of the subject pulse generators for implantation. These observations suggest that pacemaker system analyzers are not suitable for evaluating all pulse generators. Moreover, physicians must be aware of these deficiencies in order to avoid the pitfalls of relying exclusively on pacemaker system analyzer data when troubleshooting pacemaker malfunction.

Cardiology↗
PubMed1979

Occlusive disease confined to the right coronary artery: clinical features, surgical treatment and long-term follow-up in 124 patients.

The clinical presentation and surgical results in 124 consecutive patients who underwent aorta to right coronary arterial bypass surgery from January 1970 through June 1977 were reviewed. Preoperatively, 75 percent of the patients were in New York Heart Association functional class III or IV, 9 percent presented with unstable angina and 5 percent had life-threatening ventricular arrhythmias. All patients had high grade occlusive disease confined to the right coronary artery; 34 percent of the patients had associated nonsignificant disease (less than 50 percent intraluminal narrowing) of the left anterior descending or circumflex artery. Left ventricular function was normal in 63 percent and minimally impaired in 37 percent. The operative mortality rate was 1.6 percent. The course of the 122 survivors was followed up for 3.7 years. There were four late deaths, and the 5 year mortality rate was 4.0 percent. Eight patients were reoperated on because of recurrence of symptoms and occlusion of the graft or progression of occlusive disease of the other major coronary arteries, or both. Of the remaining 110 patients, 98 are either in functional class I or II, 60 are taking no cardiovascular medications, 52 are working full time without angina nad 73 are asymptomatic. In summary, bypass surgery for isolated right coronary artery disease has a low mortality rate and results in excellent long-term symptomatic improvement.

Adult↗