How to Implant Left Bundle Branch Pacing Lead in Routine Clinical Practice

Authors, Journal, Affiliations, Type, DOI

• Authors: Keping Chen, MD, PhD, FHRS, FESC; Yuqiu Li, MD, PhD — who "contributed equally to this study" (ORCID for Keping Chen: 0000-0002-3848-179X)
• Journal: J Cardiovasc Electrophysiol 2019;30:2569–2577. © 2019 Wiley Periodicals, Inc. Published under the section heading INNOVATIVE TECHNIQUES. Received 20 June 2019; revised 24 August 2019; accepted 9 September 2019
• Affiliation: State Key Laboratory of Cardiovascular Disease, Arrhythmia Center, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, China
• Type: Procedural technique guide — a step-by-step "how to" description of LBBP implantation. The schema has no value for this format, so source_type: other is used. It presents no cohort of its own: the patients in Figures 1–8 are illustrative, and the only quantitative figures cited are from the group's previous studies (reference 11, Europace 2019, and reference 12, the N = 70 bradycardia series). Every recommendation is single-centre expert practice
• DOI: 10.1111/jce.14190
• Disclosures: None. Funded by the National Natural Science Foundation of China, Grant/Award Number 81870260
• Why it matters here: this is the primary procedural source for the technique the wiki's Implantation Technique section describes, from the group that developed the transventricular-septal approach. It is also the origin of a safety rule the wiki did not previously carry (backup pacing in LBBB — see below), and of two recommendations that conflict with guidance already recorded in this wiki

Overview

This is the canonical "how to implant an LBBP lead" reference, written by the Fuwai group that helped originate the transventricular-septal approach. It describes the whole manoeuvre in practical sequence: the tools (Medtronic SelectSecure 3830 with the C315 HIS sheath, an EP recorder, and a pacing system analyser); two strategies for finding the pacing site — a single-lead method (using either the His bundle region or the tricuspid valve annulus as the fluoroscopic marker) and a dual-lead method for difficult anatomies; the paced-QRS landmarks that signal an appropriate entry point (an LBBB pattern with a "W" notch at the nadir of V1, positive in lead II, biphasic in lead III); the four to five clockwise turns that secure the lead, confirmed by a myocardial injury current; and the stopping rule — cease advancement the moment right bundle branch delay appears in V1/V2. Depth is assessed chiefly by ring-electrode capture, which the paper makes quantitative by pairing the 3830's 9 mm helix-to-ring spacing with a normal septal thickness of 6–11 mm. Beyond the mechanics, its most consequential content is what it advises against: it warns against multiple implantation attempts, and against chasing the left bundle branch potential and selective capture too hard — both framed as ways to avoid perforating the left ventricle.

Keywords

lead implantation, left bundle branch pacing, physiological pacing

Key Takeaways

Abstract

• The clinical rationale: LBBP is characterised by a low and stable pacing capture threshold, a relatively narrow QRS duration due to fast left ventricular activation, and direct excitation of the diseased left bundle branch
• The aim: to describe the methods, procedural skills, and clinical implications of performing LBBP implantation
• The methods in one line: LBBP is achieved by a transventricular-septal approach, with two methods to identify the lead-placement location — the single-lead method and the dual-lead method. The unique transition of the paced QRS morphology and pacing parameter changes guide the lead's advancement to the left side of the interventricular septum
• The conclusion, stated cautiously: "Clinical development of LBBP is at an early but encouraging phase with increasing clinical use, and a standardized procedure with improved delivery tools and pacing leads is needed, as well as long-term efficacy and safety"

1 | Introduction

• The problem chain motivating LBBP: traditional RV pacing increases the risk of decreased quality of life, heart failure, and atrial fibrillation in patients needing frequent pacing; hence a decade of interest in physiological pacing
• HBP utilises the native conduction system and is physiological, with demonstrated benefit in bradycardia and heart failure — but has limitations: operational difficulty with relatively long fluoroscopic exposure times and sometimes high and unstable capture thresholds. Moreover HBP often fails in patients with infra-Hisian block or proximal LBBB
• LBBP therefore emerged as an alternative, carrying a low and stable threshold, relatively narrow QRSd, and direct excitation of the diseased LBB
• The paper's lineage, stated by the authors: their previous study demonstrated procedural and clinical feasibility of LBBP via a transventricular-septal approach (ref 11, Europace 2019); they then reported success rate, safety, and 3-month follow-up outcomes (ref 12, the N = 70 series)

1.1 | Definition of LBBP — the three capture categories as defined here

• LBBP requires all three of:
  1. A paced QRS on 12-lead ECG showing the pattern of right bundle branch conduction delay (RBBD), or improving LBB conduction in patients with LBBB
  2. A left bundle branch potential can be recorded
  3. A fast peak left ventricular activation time (LVAT) in V5/V6
  • The paced QRSd is usually <120 ms, "according to our study in patients with bradycardia (N = 70)"
• Selective LBBP (S-LBBP) — four criteria:
  1. Paced QRS shows RBBD, usually an rSR pattern in V1 due to delayed RBB activation
  2. An isoelectric interval between the pacing spike and ECG QRS onset
  3. The spike-to-QRS-onset interval is almost identical to the left bundle potential-to-QRS-onset interval
  4. A local ventricular electrogram is present as a discrete component
• Nonselective LBBP (NS-LBBP) — three criteria:
  1. Paced QRS shows RBBD, usually a QR pattern in V1 due to delayed RV activation
  2. No isoelectric interval between pacing spike and QRS onset
  3. The local ventricular EGM shows direct capture of local tissue by the pacing stimulus

1.2 | Implant tools and equipment requirements

1. SelectSecure pacing lead (Model 3830, 69 cm; Medtronic) with an exposed 1.8-mm active helix, and a Select Site fixed-curve sheath (Model C315 HIS; Medtronic)
2. Electrophysiological multichannel recorder to record intracardiac EGMs and the 12-lead ECG simultaneously
3. Pacing system analyser (PSA) to test pacing parameters and record the intracardiac EGM via the pacing lead; the test cable is connected to both the EP recorder and the PSA through a bridge cable

1.3 | Implant procedure and methods

• LBBP is achieved via the transventricular-septal approach
• ⚠ The safety rule the wiki did not previously carry: "For patients with LBBB, it is critical to place a temporary pacing lead for backup pacing BEFORE LBBP lead placement, to avoid inadvertent complete heart block caused by the RBB block due to temporary mechanical injury." In other words, the manoeuvre itself can transiently block the right bundle in a patient whose left bundle is already diseased — with no escape rhythm
• A unipolar configuration is used for pacing and recording during implantation
• Two methods to identify the lead-placement location: the single-lead method (SLM) and the dual-lead method (DLM)

1.3.1 | Single lead method (SLM) — two approaches

• Approach 1 — the His bundle region as an anatomical marker:
  • The sheath with the pacing lead is first placed in the His bundle region near the tricuspid valve annulus under a 30° right anterior oblique view, where the His bundle potential can be recorded and the fluoroscopic image of the His location saved as a marker
  • The sheath is then advanced toward the ventricular septum, inferior to the septal leaflet of the tricuspid valve, where LBBP is attempted on the right side of the interventricular septum — usually 10 to 20 mm away from the His bundle region
• Approach 2 — the tricuspid valve annulus as an anatomical marker: the sheath with the pacing lead directly crosses the tricuspid valve and identifies the pacing site on the right side of the interventricular septum. This is the fallback when the His bundle region cannot be localised
• Positioning and the first pacing check: the sheath is placed perpendicularly against the septum by minimal counter-clockwise rotation, the helix gently advanced out of the sheath tip, and pacing applied at 2.0 V/0.5 ms or 5 V/0.5 ms
• What an appropriate site looks like — the initial paced QRS shows LBBB morphology, usually with:
  • QRSd <150 ms
  • A notch (the "W" waveform) at the nadir of the QRS in lead V1
  • A positive QRS in lead II
  • A biphasic QRS in lead III
• Fixation and advancement: initial fixation is four to five clockwise turns of the pacing lead. A 30° LAO view then confirms the distal lead remains perpendicular to the septum. The lead is further rotated clockwise with a certain force so the tip penetrates the endocardium into the septum
• Monitoring during advancement: pacing is applied intermittently while paced QRS morphology and pacing electrical parameters are closely monitored
• 🔑 The stopping rule: "Once the paced QRS morphology shows RBBD in lead V1/2 on the surface ECG due to delayed activation of the RBB — for example, meeting the LBBP criteria as described before — the lead advancement should be ceased."

1.3.2 | Dual lead method (DLM) — two approaches

• Uses two sets of 3830 leads and C315 HIS sheaths
• Approach 1: the first lead is placed in the His bundle region as an anatomical marker, or to assess the block site if the patient has LBBB. The second sheath/lead is then advanced to the septum inferior to the septal leaflet of the tricuspid valve, usually 10–20 mm from the His bundle region, and the transseptal placement proceeds as for the SLM
• Approach 2: used when an initial LBBP attempt with one lead does not achieve satisfactory QRS morphology and pacing parameters. A second lead is advanced to find a more optimal pacing site while the first serves as an anatomic reference. Once optimal paced QRS and parameters are achieved, the first lead is moved and placed in the right atrium
• When to use DLM: "We usually use the DLM in patients with an enlarged right atria and/or RV, which is more difficult to identify the desired pacing site"

Two mechanistic observations that guide the manoeuvre

• The injury current is the contact signal: "From a technical perspective, a myocardial injury current signifies an excellent tissue contact, which is generally observed after the pacing lead is rotated four to five turns clockwise. No injury current or low amplitude of injury current indicates that either the lead helix is not screwed into the myocardium or the myocardial contact is inappropriate. If that happens, the lead should be screwed back and relocated"
• The LBB potential is dynamic, not static: because the LBB spreads widely beneath the left-sided septal endocardium, there is a dynamic change of the LBB potential during the transventricular-septal placement. As the tip advances, the LBB potential gradually appears and its amplitude gradually increases, as does the injury current of the LBB

1.4 | Measurement of parameters

• After implantation, the parameters to assess: capture threshold, lead impedance, R-wave amplitude, paced QRSd, peak LVAT, LBB potential amplitude, the stimulus-to-QRS-onset interval, and the LBB-potential-to-QRS-onset interval
• Peak LVAT is measured from the pacing stimulus to the QRS upstroke in V5/V6, at both the capture threshold and high output (5 V/0.5 ms)
• In some patients the ring electrode may itself enter the ventricular septum, so the ring electrode capture threshold should be measured
• Two practical cautions: the local ventricular EGM used to distinguish S-LBBP from NS-LBBP may not be clearly visualised with unipolar recording on the pacing lead; and bipolar pacing parameters should be tested once the ring electrode is out of the tip of the sheath

1.5 | Assessment of the depth of the pacing lead inside the ventricular septum

The numbers that make depth assessment quantitative, because they are absent from the other technique descriptions in this wiki:

• Normal ventricular septal thickness: 6 to 11 mm

• The 3830 helix electrode length: 1.8 mm

• The space between the lead helix and the ring electrode: 9 mm

• Method 1 — ring electrode capture (routinely used): once the ring electrode captures tissue at 5 V/0.5 ms, it signifies the helix electrode is already at or near the left side of the ventricular septum. An illustrative case showed the ring electrode pacing at 0.2 V/0.5 ms capturing local tissue while the LBB potential was recorded by the helix. Once the ring electrode captures, any further advancement of the pacing lead should be conducted carefully

• But ring electrode capture is NOT necessary — a point of departure from other guidance:

  • Septal thickness varies between individuals, and between locations in the same person
  • The lead is not completely advanced perpendicular to the ventricular septum
  • So ring capture "is helpful to confirm the depth of the lead, but not necessary, especially for patients whose thickness of the ventricular septum is thin"
  • The recommendation instead: assess septal thickness BEFORE implantation, so the operator knows how deep the tip can safely be advanced

• Method 2 — fluoroscopy with contrast injection: useful when the paced QRS morphology has not changed despite further screwing, or when the septum is thin

• Sheath removal: the C315 sheath is slit and removed while adequate lead slack is retained — and "the sheath for the LBBP lead placement should be slit AFTER the implantation of the other pacing leads to reduce the risk of LBBP lead dislodgement"

1.6 | Programming

• Because the lead sits in left-sided septal tissue, sensing amplitude is high and capture threshold is low — so ventricular undersensing and far-field atrial oversensing can be avoided
• Ventricular safety pacing and autocapture management can be turned on
• AV delay should be individualised, considering AV conduction and bundle branch block. Automatic AV search is routinely turned on in sinus node dysfunction and intermittent AVB
• In LBBB specifically: the ECG QRSd is assessed during an AV delay adjustment from 40 ms to the intrinsic PR interval, and the AV delay generating the narrowest QRSd is programmed

1.7 | Tips and advice (four)

1. Confirm perpendicularity on the right side under LAO 30°. In the majority of patients pacing here produces an LBBB pattern with the notch at the V1 nadir ("W"), positive in lead II, biphasic in lead III — "This phenomenon suggests an ideal site where the lead can be screwed toward the left side of the septum. However, this may not occur in every patient"
2. Watch the transition continuously. The transition of the paced QRS morphology and the notch shift in V1 are continuously monitored; the transition indicates the lead tip's location and is used to guide the stopping point of advancement. Conversely, if the paced QRS shows undesirable changes, or the lead unwound after several rotations, this may indicate insufficient advancement or an unsuitable position — consider repositioning
3. Monitor pacing parameters closely — and note the direction of the signs:
   • Low capture threshold and high pacing impedance suggest the lead is inside the septum
   • A sudden DECREASE of lead impedance, sensed R-wave amplitude, and/or loss of capture indicate the helix has entered the left ventricular chamber — i.e. LV perforation. The lead should be rotated back and relocated
4. Monitor PVC morphology during advancement — the morphologic characteristics of the premature ventricular contractions may represent the depth of the pacing lead in the ventricular septum

1.8 | Considerations

1.8.1 | Criteria for LBBP

• LBBP is characterised by RBBD, improved LBB conduction in patients with LBBB, and fast LVAT, and it matters to observe a relatively narrow QRSd
• A large-amplitude LBB potential is a good indicator for LBBP — "however, the left bundle branch potential is observed in approximately 70% of cases" (citing ref 12)
• In clinical practice it may be difficult to meet all criteria in every patient.
• ⚠ "We do not recommend multiple attempts for LBBP lead placement because repeated attempts of transventricular-septal lead position will increase potential risks of local myocardial injury and left ventricular perforation." — see the Contradictions section below; this is at odds with the repositioning practice recorded elsewhere in this wiki

1.8.2 | Selective LBBP and nonselective LBBP pacing

This subsection is the paper's most argumentative content, and it runs against the framing used by most of the capture-confirmation literature:

• Because the LBB spreads beneath the endocardium, and given the immediate proximity of the muscular septum and the non-penetrating portion of the LBB, nonselective capture is EXPECTED MORE FREQUENTLY than selective
• S-LBBP is usually observed when the pacing output is low — and may not be clearly observed at all, because unipolar pacing and recording during implantation make local EGMs difficult to record
• "While theoretically S-LBBP is preferred by an operator, it is not practical to achieve this in every patient in the clinical setting" — longer procedural time and more attempts may be needed, and routine pacing outputs after implantation will capture the local myocardial tissue in the majority of patients
• ⚠ The safety argument against chasing selective capture: "overemphasis of left bundle branch potential and S-LBBP can increase the risk of LV perforation due to overscrewing the lead too deeply into the LV septum"
• And the question is left open: "The potential difference between S-LBBP and NS-LBBP in clinical practice should be further investigated"

1.8.3 | Potential complications

• Transventricular-septal LBBP "may cause potential risks of septal hematoma, left ventricular perforation, and other complications"
• Long-term stability and integrity of the pacing lead need to be further evaluated
• Extraction is flagged as its own problem: "Lead extraction may be another complicating issue due to a significant distal part of the lead buried inside the septum."
• The forward look: "Specific delivery tools and pacing leads should be developed to make LBBP implantation safer and simpler"

2 | Conclusions

• LBBP is achieved by the transventricular-septal approach; "in our experience, LBBP can be safely performed in most patients requiring pacemaker therapy"
• The evolution of their own indications, stated plainly: "we initially performed LBBP mostly in patients with symptomatic bradycardia with normal QRS morphology, but have now expanded this therapy to some patients with heart failure and ventricular desynchrony caused by LBBB"
• The core teaching point: during implantation, the unique transition of the paced QRS morphology and pacing parameter changes are important for guiding lead advancement to the left side of the interventricular septum
• Restated limitation: clinical development is "at an early but encouraging phase", a standardised procedure, improved delivery tools and pacing leads are needed, as is long-term efficacy and safety data

Figures (illustrative cases)

Figures 1–8 span eight images, all of which are real figures (this file was converted by pymupdf4llm, which extracts selectively):

• Fig 1 — S-LBBP vs NS-LBBP in one patient with sinus node dysfunction: S-LBBP (0.5 V/0.5 ms) with an isoelectric window and rSR in V1; NS-LBBP (0.7 V/0.5 ms) with no isoelectric window and QR in V1
• Fig 2 — SLM using the His region as marker (panels A–H): His potential with HV 48 ms; pacing at 5.0, 2.0 and 0.2 V/0.5 ms at successive depths; LBB potential-to-QRS 28 ms
• Fig 3 — SLM using the tricuspid valve annulus as marker: the notch in V1 changing as the tip moves right→left; LBB potential-to-QRS 20 ms
• Fig 4 — DLM with a His lead plus an LBBP lead: HV 42 ms, LBB potential-to-QRS 24 ms
• Fig 5 — DLM finding a better site in a patient with RBBB after CABG: first lead gave QRSd 120 ms / peak LVAT 88 ms; the second lead gave QRSd 110 ms / peak LVAT 78 ms at 0.7 V/0.5 ms, with LBB potential-to-QRS 20 ms, and ring pacing at 0.2 V/0.5 ms
• Fig 6 — dynamic growth of the LBB potential amplitude during rotation (EGM gain ×64)
• Fig 7 — growth of the injury current of the LBB potential during rotation
• Fig 8 — dynamic PVC morphology changes during rotation toward the left side of the septum

Limitations of the document

Authors' own stated limitations

• "Clinical development of LBBP is at an early but encouraging phase" — a standardised procedure, improved delivery tools and pacing leads are needed, as are long-term efficacy and safety data
• Long-term stability and integrity of the pacing lead need further evaluation, and extraction is an unresolved problem given how much of the lead is buried in the septum
• The S-LBBP vs NS-LBBP difference in clinical practice "should be further investigated" — the authors explicitly decline to resolve the question they raise
• The technique cannot always be completed as described: it "may be difficult to meet all the criteria of LBBP at implantation in every patient", and the ideal entry-point ECG "may not occur in every patient"

Additional limitations evident in the study

• No cohort of its own, and therefore no outcomes. This is a technique description illustrated by individual cases; the Figures each show one patient. The only quantitative statements (N = 70, QRSd <120 ms, LBB potential in ~70%) are imported from the group's previous studies (refs 11–12), so they carry whatever limitations those studies had — neither of which is in this wiki, so the claims arrive here unverifiable
• Single-centre expert practice, presented as such. Nearly every recommendation is framed as "in our experience" or "we usually use", and none is compared against an alternative approach. The DLM trigger — "patients with enlarged right atria and/or RV" — is offered without a definition, incidence, or success rate
• The technique is bound to one lead and sheath combination (Medtronic 3830 + C315 HIS, both named in the tools list). Nothing indicates whether the same landmarks and stopping rules transfer to other leads — which matters, because the wiki's SDL sources use the Biotronik Solia S60 with a Selectra3D sheath and a different helix mechanism
• Several instruction-critical numbers have no stated derivation. The 10–20 mm distance from the His bundle region, the four to five clockwise turns, the 6–11 mm septal thickness, and the 9 mm helix-to-ring spacing are all given as facts. Only the helix length (1.8 mm) and septal thickness plausibly come from the manufacturer and anatomy; the rest appear to be the group's habits, and none is accompanied by a range across patients or an error rate
• The two most consequential recommendations are stated without supporting data. Both "we do not recommend multiple attempts" and "overemphasis of LBB potential and S-LBBP can increase the risk of LV perforation" are asserted on mechanistic reasoning alone — no perforation rates by attempt number, no comparison of outcomes. They are plausible and safety-conservative, but they are expert opinion, not measurement, and they sit in direct tension with registry data (see Contradictions)
• The LBB-potential figure compounds an existing inconsistency rather than resolving it. "Approximately 70%" here joins 14% (De Pooter, stylet leads), 40.6% (programmed septal stimulation) and 50–80% (the founding 2019 review) already recorded in this wiki. A range that wide across cohorts strongly suggests the rate is a function of lead type, recording configuration, gain and operator effort — not a stable property — and this paper, by noting that unipolar recording obscures local EGMs, offers part of the explanation without quantifying it
• No procedural time, fluoroscopy time, success rate, or learning-curve data. For a paper whose purpose is procedural guidance, the absence of any efficiency or success metric is notable — particularly the learning curve, since the same group's technique is being taught to operators who will pass through it
• Rating rationale: rated medium. In its favour: it is the canonical procedural reference from a group that originated the approach, published in a peer-reviewed technique section, illustrated with eight figures, and unusually specific about the manoeuvre (landmarks, turn counts, stopping rules, and the sign of the impedance change that indicates perforation). Its claims are descriptive and technical rather than statistical, so there is comparatively little for it to be wrong about. Against: no cohort, no outcomes, no comparator, single centre, and its two strongest recommendations are unquantified expert opinion. It is a better source than a single-case teaching piece, and a lesser one than any of the registry studies in this wiki — hence medium

Key Concepts Mentioned

• concepts/Left-Bundle-Branch-Area-Pacing — the technique this paper describes end to end
• concepts/Conduction-System-Pacing — the umbrella category
• concepts/His-Bundle-Pacing — the alternative the introduction frames itself against, and the marker used in two of the site-identification approaches
• Single lead method (SLM) / Dual lead method (DLM) — the two site-identification strategies, each with two approaches; DLM reserved for enlarged RA/RV or a failed first attempt
• His bundle region vs tricuspid valve annulus as fluoroscopic markers — the fallback relationship between them (TV annulus when the His cannot be localised)
• The "W" notch in V1 — the ideal entry-point signature: notch at the QRS nadir in V1, positive in II, biphasic in III, QRSd <150 ms
• Myocardial injury current — the marker of good tissue contact, expected after 4–5 clockwise turns; absent or low amplitude means the helix is not properly engaged
• Dynamic LBB potential — appears gradually and grows in amplitude as the tip advances, along with its injury current
• Ring electrode capture — the primary depth-assessment method, made quantitative by the 9 mm helix-to-ring spacing against 6–11 mm septal thickness; explicitly not necessary
• The stopping rule — cease advancement when RBBD appears in V1/V2, i.e. on meeting LBBP criteria
• LV perforation — signalled by a sudden decrease in lead impedance, sensed R-wave amplitude, or loss of capture
• S-LBBP vs NS-LBBP — with the paper's argument that NS-LBBP is expected more frequently and that chasing selective capture raises perforation risk
• Lead extraction — flagged as unresolved because a significant distal portion of the lead is buried in the septum

Key Entities Mentioned

• concepts/Left-Bundle-Branch-Area-Pacing — primary concept page
• Medtronic SelectSecure 3830 (69 cm, 1.8 mm exposed helix) and Medtronic Select Site C315 HIS sheath — the specific tools the technique is bound to; the same lead as in sources/lbbap-jacc-2019 and others, but a different sheath and lead than the Biotronik SDL sources
• Fuwai Hospital / Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing — the single investigating centre; the group that developed the transventricular-septal approach (refs 11–12 are their own)
• Keping Chen — corresponding author, ORCID 0000-0002-3848-179X
• National Natural Science Foundation of China (grant 81870260) — the disclosed funder; the paper reports no other disclosures
• Wiley Periodicals — publisher (J Cardiovasc Electrophysiol)

Wiki Pages Updated

• Created: wiki/sources/lbbap-implant-jce-2019.md
• Updated: wiki/concepts/Left-Bundle-Branch-Area-Pacing.md
• Updated: wiki/sourceindex.md
• Updated: wiki/wikiindex.md