Effect of Pacing Mode and Cumulative Percent Time Ventricular Paced on Heart Failure and Atrial Fibr - PowerPoint PPT Presentation

1 / 16
About This Presentation
Title:

Effect of Pacing Mode and Cumulative Percent Time Ventricular Paced on Heart Failure and Atrial Fibr

Description:

... Atrial Fibrillation in Patients with Sinus Node Dysfunction and Baseline QRS Duration ... and may increase risk of heart failure and atrial fibrillation. ... – PowerPoint PPT presentation

Number of Views:166
Avg rating:3.0/5.0
Slides: 17
Provided by: michaelos
Category:

less

Transcript and Presenter's Notes

Title: Effect of Pacing Mode and Cumulative Percent Time Ventricular Paced on Heart Failure and Atrial Fibr


1
Effect of Pacing Mode and Cumulative Percent Time
Ventricular Paced on Heart Failure and Atrial
Fibrillation in Patients with Sinus Node
Dysfunction and Baseline QRS Duration lt120
Milliseconds in MOSTA MOST Sub-Study
  • Michael O. Sweeney, Anne S. Hellkamp, Arnold J.
    Greenspon, Robert Mittleman, John McAnulty,
    Kenneth Ellenbogen, Roger Freedman, Kerry L. Lee,
    Gervasio A. Lamas, for the MOST Investigators
  • Circulation 2003, in press

2
MOST Sub-Study
  • Background
  • DDDR pacing preserves AV synchrony and reduces
    CHF compared to VVIR pacing in SND.
  • DDDR pacing results in prolonged QRS durations
    (QRSd) due to ventricular desynchronization.
  • Hypothesis
  • DDDR pacing often results in prolonged QRS
    duration (QRSd) due to ventricular
    desynchronization in patients with normal
    baseline QRSd and may increase risk of heart
    failure and atrial fibrillation.

Sweeney MO, et al. Circulation 2003, in press
3
MOST Sub-Study
  • Methods
  • Baseline QRSd obtained from 12-lead EKG prior to
    IPG implant in MOST (a 2,010 patient, 6-year
    randomized trial of DDDR vs. VVIR pacing in SND).
  • Cumulative time ventricular paced was
    determined from stored pacemaker diagnostic data.
  • Baseline QRSd lt120 ms was observed in 1332
    patients 702 were randomized to DDDR 640 to
    VVIR.

Sweeney MO, et al. Circulation 2003, in press
4
MOST Sub-Study Results
  • CumVP was greater in DDDR (90) vs. VVIR (51).
  • The rates of CHF hospitalization increased with
    CumVP

Sweeney MO, et al. Circulation 2003, in press
5
MOST Sub-study Risk of HFH Relative to a DDDR
Patient with Cum VP 0
  • Risk of HFH increased between 0 and 40 Cum VP,
    but was level at CumVP above 40.
  • Risk can be reduced to about 2 if ventricular
    pacing is minimized.

Sweeney MO, et al. Circulation 2003, in press
6
MOST Sub-Study Risk of HFH Relative to a VVIR
Patient with Cum VP 0
  • Risk of CHF was constant between 0 and 80 Cum
    VP and increased by as much as 2.5-fold when
    CumVP exceeded 80.
  • Risk cannot be reduced regardless of minimization
    of ventricular pacing.

Sweeney MO, et al. Circulation 2003, in press
7
MOST Sub-Study CHF Risk
  • DDDR
  • CumVP gt40 was associated with 3 times increased
    risk of CHF hospitalization (p0.02).
  • The risk of CHF hospitalization increased by 54
    for each 10 increase in CumVP (Hazard ratio
    1.54 1.01, 2.36), p0.05) between 0 and 40.
  • VVIR
  • CumVP gt 80 was associated with 2.6 times
    increased risk of CHF hospitalization (p0.007).
  • The risk of CHF hospitalization increased by 96
    for each 10 increase in CumVP (Hazard ratio
    1.96 1.39, 2.77, p0.0001) above 80.

Sweeney MO, et al. Circulation 2003, in press
8
MOST Sub-Study
P0.047
Sweeney MO, et al. Circulation 2003, in press
9
MOST Sub-Study
P0.0046
Sweeney MO, et al. Circulation 2003, in press
10
MOST Sub-studyConclusions CHF
  • Higher rates of CHF hospitalization were
    associated with higher Cum VP
  • Cum VPlt10 was associated with the lowest rates
    of CHF hospitalization (DDDR 2, VVIR 7).
  • Cum VP gt90 was associated with the highest
    rates of CHF hospitalization (DDDR 12, VVIR
    16).
  • Ventricular pacing in the DDDR mode more than 40
    confers a 3-fold increased risk of heart failure
    hospitalization but can be reduced to about 2 if
    ventricular pacing is minimized.

Sweeney MO, et al. Circulation 2003, in press
11
MOST Sub-studyConclusions CHF
  • In the VVIR mode, the risk of CHF hospitalization
    was level below CumVP ?80 but cannot be
    reduced regardless of minimization of ventricular
    pacing. This risk is increased by as much as
    2.5-fold when CumVP exceeds 80.

12
MOST Sub-study AF Risk
Risk of AF increases linearly with CumVP up to
?80-85 in both DDDR and VVIR
Sweeney MO, et al. Circulation 2003, in press
13
MOST Sub-study AF Risk
Sweeney MO, et al. Circulation 2003, in press
14
MOST Sub-study AF Risk
Sweeney MO, et al. Circulation 2003, in press
15
MOST Sub-studyConclusions AF
  • Relationship between risk of AF and CumVP was
    similar between pacing modes
  • Risk of AF showed a linearly increasing
    relationship with increased CumVP from 0 pacing
    up to 80-85 pacing in both pacing modes.
  • Within this range, the risk of AF increased by 1
    for each 1 increase in CumVP (DDDR hazard ratio
    1.01 1.004, 1.022 p0.012 VVIR 1.01 1.001,
    1.01, p0.025).

Sweeney MO, et al. Circulation 2003, in press
16
MOST Sub-StudyOverall Conclusions
  • The adverse effects of forced ventricular
    desynchronization probably explain the difficulty
    in demonstrating a mortality and stroke benefit
    with physiologic (DDDR) compared to ventricular
    (VVIR) pacing in randomized trials.
  • Further research is necessary to clarify the role
    of electrical unloading of the left ventricle
    using minimal ventricular pacing strategies in
    SND and normal QRSd.

Sweeney MO, et al. Circulation 2003, in press
Write a Comment
User Comments (0)
About PowerShow.com