Iatrogenic ventricular dyssynchrony: a preventable cause of heart failure with right ventricular pacing?

Pacemaker-based analysis of atrioventricular conduction and atrial tachyarrhythmias in patients with primary sinus node dysfunction

BACKGROUND

Most patients with symptomatic sinus node disease (SND) receive DDDR pacemakers (PM) in order to cover SND and atrioventricular (AV) block from the outset. But the concern about adverse effects of right ventricular pacing (RVP) is increasing. So far, data on the incidence of AV block in SND are based on clinical events. The study undertakes to assess and appraise AV block and atrial tachyarrhythmias (AT) from memory and electrograms of a dual-chamber PM set to an AAIR-DDDR switch mode (AAISafeR).

METHODS

A dual-chamber PM incorporating the AAISafeR mode was implanted in 58 patients (70 +/- 10 years, 28 males) with SND, but without AV block >I. AV block and AT episodes were retrieved from the PM memory and validated from electrograms. AV block episodes were classified potentially relevant while comprising AV block III or AV block I/II during exercise.

RESULTS

The patients experienced a median of 90 (interquartile range 7-1,084) commutations. Possibly relevant AV block occurred in 32 patients (55%). Validation revealed high-quality PM-based categorization. The RVP prevalence was 0% (0-16%). The median AT prevalence was 0.03 (0-26) min/day. RVP was the only multivariate predictor of AT (P = 0.001).

CONCLUSIONS

Potentially relevant AV block occurs frequently in patients with SND. Nonetheless, the RVP prevalence is kept low through the AAISafeR mode. The protection of SND patients with demand-actuated ventricular pacing appears reasonable. The AT prevalence is low in SND patients treated by the AAISafeR mode. Even low RVP proportions appear to favor AT. Prospective evaluation is needed.

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. The guideline will only be effective when the physicians or cardiac device caregivers have the knowledge and skills to optimally program and match device therapies and algorithms to individual patient needs.