Biomedical subjects

Kenneth Ellenbogen

Publications and source records attributed to Kenneth Ellenbogen.

4 recordsLinked to original sources

PubMed2005

Time to resumption of driving after implantation of an automatic defibrillator (from the Dual chamber and VVI Implantable Defibrillator [DAVID] trial).

The time to resumption of driving after insertion of an implantable cardioverter-defibrillator (ICD) was evaluated in the Dual Chamber And VVI Implantable Defibrillator trial. Most patients were advised not to drive for 3 to 6 months after the ICD was implanted. Patients were surveyed at 3-, 6-, or 9-month intervals to characterize their driving habits, with 101 of 137 (73.7%), 98 of 146 (67.1%), and 79 of 135 (58.5%) responding. Of respondents, 82% recalled being told not to drive for a specified time after ICD implantation. These patients generally obeyed recommendations (association between recommended time and time of resumption, p <0.001) from medical personnel.

Arrhythmias, Cardiac↗

PubMed2003

Termination of paroxysmal supraventricular tachycardia by tecadenoson (CVT-510), a novel A1-adenosine receptor agonist.

OBJECTIVES: The aim of this study was to evaluate tecadenoson safety and efficacy during conversion of paroxysmal supraventricular tachycardia (PSVT) to sinus rhythm. BACKGROUND: Tecadenoson (CVT-510), a novel adenosine receptor (Ado R) agonist, selectively activates the A1 Ado R and prolongs atrioventricular (AV) nodal conduction at doses lower than those required to cause A2 Ado R-mediated coronary and peripheral vasodilation. Unlike adenosine, which non-selectively activates all four Ado R subtypes and produces unwanted effects, tecadenoson appears to terminate AV node-dependent supraventricular tachycardias without hypotension and bronchoconstriction. METHODS: In this open-label, multicenter, dose escalation study, tecadenoson was administered to 37 patients (AV node re-entrant tachycardia, n = 29; AV re-entrant tachycardia, n = 8) with inducible PSVT sustained for > or =1 min during an electrophysiology study. Seven regimens (0.3 to 15 microg/kg) of up to two identical tecadenoson intravenous bolus doses were administered. RESULTS: After the first or second bolus, PSVT converted to sustained sinus rhythm for > or =5 min in 86.5% (32/37) of the patients, with 91% (29/32) of the conversions occurring after the first bolus (most within 30 s), coincident with anterograde conduction block in the AV node. No effects on sinus cycle length (SCL) or systolic blood pressure were observed. The atrial-His (AH), but not the His-ventricular (HV) interval was prolonged up to 5 min after the final tecadenoson bolus, returning to baseline by 10 min. Tecadenoson was generally well tolerated. CONCLUSIONS: In this study, tecadenoson rapidly terminated sustained PSVT by depressing AV nodal conduction without causing hypotension. After sinus rhythm restoration, there was minimal AH interval prolongation without HV interval or SCL prolongation.

Adenosine↗

PubMed2002

Ventricular pacing or dual-chamber pacing for sinus-node dysfunction.

BACKGROUND: Dual-chamber (atrioventricular) and single-chamber (ventricular) pacing are alternative treatment approaches for sinus-node dysfunction that causes clinically significant bradycardia. However, it is unknown which type of pacing results in the better outcome. METHODS: We randomly assigned a total of 2010 patients with sinus-node dysfunction to dual-chamber pacing (1014 patients) or ventricular pacing (996 patients) and followed them for a median of 33.1 months. The primary end point was death from any cause or nonfatal stroke. Secondary end points included the composite of death, stroke, or hospitalization for heart failure; atrial fibrillation; heart-failure score; the pacemaker syndrome; and the quality of life. RESULTS: The incidence of the primary end point did not differ significantly between the dual-chamber group (21.5 percent) and the ventricular-paced group (23.0 percent, P=0.48). In patients assigned to dual-chamber pacing, the risk of atrial fibrillation was lower (hazard ratio, 0.79; 95 percent confidence interval, 0.66 to 0.94; P=0.008), and heart-failure scores were better (P<0.001). The differences in the rates of hospitalization for heart failure and of death, stroke, or hospitalization for heart failure were not significant in unadjusted analyses but became marginally significant in adjusted analyses. Dual-chamber pacing resulted in a small but measurable increase in the quality of life, as compared with ventricular pacing. CONCLUSIONS: In sinus-node dysfunction, dual-chamber pacing does not improve stroke-free survival, as compared with ventricular pacing. However, dual-chamber pacing reduces the risk of atrial fibrillation, reduces signs and symptoms of heart failure, and slightly improves the quality of life. Overall, dual-chamber pacing offers significant improvement as compared with ventricular pacing.

Aged↗

PubMed2002

Health values before and after pacemaker implantation.

BACKGROUND: Health value or utility is the abstracted magnitude of a person's preference for quality and quantity of life. It reflects how much lifetime with the patient's current health condition a patient is willing to exchange for a life in excellent health. Health values are used in cost-effectiveness analysis as a means of calculating quality-adjusted years of life. OBJECTIVE: This study assessed the health values of elderly patients before and after pacemaker implantation. METHODS: We prospectively examined 398 patients from the Pacemaker Selection in the Elderly study, in which patients were randomized to either VVIR or DDDR mode. Health values were estimated with the time tradeoff method before implantation and at 3, 9, and 18 months after implantation. RESULTS: The mean age of patients was 76 +/- 6 years; 234 patients (59%) were male. At baseline, patients were, on average, willing to exchange 5 years of current health for approximately 4 years in perfect health (value 0.76 +/- 0.06). There was no difference in baseline health values with implant diagnosis (sinus node dysfunction n = 172, 0.72, atrioventricular block n = 227, 0.75, other diagnoses n = 39, 0.78, P = not significant). The overall improvement in health values at 3 months after pacemaker implantation was 0.165 +/- 0.4 (P =.0001). The improvement in health values was independent of pacing mode (P =.6). The time tradeoff score was modestly correlated with other measurements of health-related quality of life. The change in time tradeoff score with time was not influenced by demographic characteristics such as age and sex, diagnoses, pacing mode, employment status, or history of angina. Patients with a lower functional class at enrollment (III or IV on the Specific Activity Scale) demonstrated an absolute improvement of 23% in their health values, whereas patients in class I or II improved only by 12%, (P =.03). CONCLUSIONS: Permanent pacemaker implantation for standard indications improves health values and descriptive health status measures. The values reported here may be used as a means of calculating the cost-effectiveness of different pacing modalities.

Aged↗