32
Implant Procedure
Table 4. Criteria for Left Bundle Branch Area Pacing
a
Pacing type Criteria
Le
ventricular
septal pacing
1. Deep septal placement of the pacing lead (confirmed by the
fulcrum sign, contrast, echocardiogram, or CT)
and
2. Right bundle branch conduction delay pattern in lead V
1
(rare exceptions)
Le bundle
branch area
pacing
1. Evidence for LV septal pacing in addition to any one of the
following LBB capture criteria:
LBB capture criteria
• Nonselective to selective LBBP or nonselective to septal capture
transition during threshold testing
• Abrupt shortening of RWPT
b
or left ventricular activation time
(LVAT) in V
6
≥10 ms at high output during deep septal position
with subsequent short and constant LVAT at low output with
further advancement of the lead
• V
6
RWPT <74 ms in non-LBBB and <80 ms in LBBB
• V
6
–V
1
interpeak interval >44 ms
• Physiolog y-based criteria
a. QRS onset to RWPT ≤ native RWPT (+10 ms)
b. Stimulus to RWPT ≤ LBB potential to V
6
RWPT (+10 ms)
c. Stimulus to V
6
RWPT + 10 ms < (intrinsicoid deflection time-
transseptal conduction time) in LBBB
• Programmed deep septal stimulation demonstrating differential
capture
• Change in V
6
RWPT between (corrective) HBP and LBBP
>8 ms in LBBB
• Demonstration of LBB potential with injury current
• Demonstration of stimulus to retrograde His <35 ms or anterograde
left conduction system potential preceding ventricular electrogram
during LBBP
a
Le bundle branch area pacing includes both LV septal pacing and le bundle branch
pacing.
b
RWPT and LVAT here should be assessed starting from the stimulation artifact rather
than from inferred QRS onset.