title: Beat-to-beat variability in stroke volume during VVI pacing as predictor of hemodynamic benefit from DDD pacing.
abstract: To determine whether the magnitude of Beat-to-Beat variability in stroke volume (SV) during VVI pacing can predict hemodynamic benefit from DDD pacing, we undertook Doppler recordings of systolic and diastolic LV flow during VVI and DDD pacing in 20 patients (age 54 +/- 9 years) with DDD pacemakers implanted due to AV block. SV increased by 19% +/- 10% from VVI to DDD (P < 0.01). This increase was greater (29% +/- 9%) in patients with a ratio of early (E)/late (A) filling < 1 compared to those with E/A > 1 (10% +/- 9%) (P < 0.001). Beat-to-Beat variability in SV was greater in VVI (13% +/- 8%) compared to DDD (4% +/- 1%) (P < 0.001). Patients with E/A < 1 showed greater Beat-to-Beat variability in SV during VVI pacing (19 +/- 6%) compared to those with E/A > 1 (8% +/- 4%) (P < 0.001). Beat-to-Beat variability in SV during VVI pacing correlated with both percent change in SV from VVI to DDD (r = 0.89, P < 0.001) and E/A (r = -0.71, P < 0.001). In conclusion, patients with E/A < 1 derive greater hemodynamic benefit at rest from DDD pacing compared with E/A > 1. In addition, patients with complete AV block who show large variations in SV during VVI pacing may obtain greater hemodynamic benefit at rest from DDD pacing than patients with small variations.
authors.affiliation: Department of Medicine Clinical Cardiology, Hammersmith Hospital, Royal Postgraduate School, London, United Kingdom.
authors.forename: A
authors.initials: A
authors.lastname: Dritsas
authors.forename: J
authors.initials: J
authors.lastname: Joshi
authors.forename: S C
authors.initials: SC
authors.lastname: Webb
authors.forename: G
authors.initials: G
authors.lastname: Athanassopoulos
authors.forename: C M
authors.initials: CM
authors.lastname: Oakley
authors.forename: P
authors.initials: P
authors.lastname: Nihoyannopoulos
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001783:Blood Flow Velocity / Q000502:physiology; D002302:Cardiac Output / Q000502:physiology; D002304:Cardiac Pacing, Artificial / Q000379:methods*; D004452:Echocardiography; D015150:Echocardiography, Doppler; D005260:Female; D005544:Forecasting; D006327:Heart Block / Q000503:physiopathology / Q000628:therapy; D006339:Heart Rate / Q000502:physiology*; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D008944:Mitral Valve Insufficiency / Q000000981:diagnostic imaging / Q000503:physiopathology; D013318:Stroke Volume / Q000502:physiology*; D014262:Tricuspid Valve Insufficiency / Q000000981:diagnostic imaging / Q000503:physiopathology; D016277:Ventricular Function, Left / Q000502:physiology*