GPT 4o answer:
Absolutely — let’s break it down into two clear parts:
Traditional right ventricular (RV) pacing activates the heart in an abnormal sequence — starting at the RV apex and then propagating through the myocardium. This creates:
Dyssynchronous contraction, especially between the left and right ventricles.
Increased wall stress, especially on the LV lateral wall.
Risk of pacing-induced cardiomyopathy (PICM) over time.
By contrast, Conduction System Pacing (CSP) — such as:
His-bundle pacing (HBP) or
Left bundle branch area pacing (LBBAP)
— stimulates the native conduction pathways directly.
| Feature | RV Pacing | CSP (His or LBBAP) |
|---|---|---|
| QRS Morphology | Wide, non-physiological | Narrow, physiologic |
| Ventricular Synchrony | Lost | Preserved |
| Long-term LVEF | May decline | Better preserved |
| Risk of PICM | Higher | Lower |
| Exercise tolerance | Often reduced | Often better maintained |
His-SYNC trial and His-Alternative trial: Showed improved EF and reduced heart failure hospitalization with His bundle pacing vs. RV pacing.
LBBAP has demonstrated more stable pacing thresholds and better sensing than His pacing.
| Issue | Traditional Pacemaker | Leadless Pacemaker |
|---|---|---|
| Leads | Yes (into the venous system and heart) | None |
| Subcutaneous pocket required | None | |
| Infection risk | Higher (pocket and lead-related) | Significantly lower |
| Lead fracture/dislodgment | Common cause of failure | Absent |
| Tricuspid valve interference | Leads may cause regurgitation | No interference |
| Cosmetic/aesthetic | Bulge under skin | Invisible |
Reduced infection risk: Important in older patients or those with comorbidities.
No vascular access limitation: Ideal for patients with occluded veins or on dialysis.
Fewer mechanical complications: No lead fractures, insulation defects, or venous thromboses.
MRI compatibility: Most are MRI-safe with appropriate conditions.
Micra IDE and Post-Approval Studies (Medtronic) and Aveir IDE (Abbott): Demonstrated low complication rates and high implant success rates.
Durability: Leadless systems have shown good performance over mid-term follow-up (~5–7 years), with next-gen devices improving battery longevity and retrievability.
The next generation of pacing will likely combine physiological pacing (CSP) with leadless technology, offering:
Natural activation of the heart
No leads, no pocket, and fewer complications
Longer battery life and fewer reinterventions
Abbott’s Aveir CSP system (in trials) aims to combine:
Leadless form factor with
Conduction system capture (e.g., Left Bundle Branch Area)
This could replace not only single-chamber pacemakers but also open the door for leadless dual-chamber pacing or even CRT (Cardiac Resynchronization Therapy) in a minimally invasive way.
Conduction System Pacing preserves natural heart function better than RV pacing.
Leadless Pacemakers eliminate most hardware-related complications of traditional systems.
Together, they represent the future of pacing therapy: more physiological, less invasive, and more durable — especially important as the pacing population gets older, more comorbid, and more active.
Would you like a visual comparison chart or a PDF you could share with a clinician?
Here is a detailed comparison chart between Traditional RV Pacing, Conduction System Pacing (CSP), and Leadless Pacemakers, showing why CSP and leadless technology represent the future of cardiac pacing:
| Feature | Traditional RV Pacing | Conduction System Pacing (CSP)(His / LBBAP) | Leadless Pacemakers(e.g., Aveir VR, Micra) |
|---|---|---|---|
| Pacing site | RV apex or septum | His bundle or left bundle branch | RV septum (currently) |
| Electrical activation | Non-physiologic (myocyte-to-myocyte) | Physiologic (via His-Purkinje system) | Non-physiologic (but can evolve to CSP) |
| QRS duration | Wide | Narrow (near-normal) | Wide (unless CSP becomes available) |
| Ventricular synchrony | Dyssynchronous | Synchronous | Dyssynchronous for now |
| Heart failure risk | Higher (due to pacing-induced cardiomyopathy) | Lower | Intermediate |
| Lead-related complications | Common (fractures, dislodgment, venous occlusion) | Present (though more precise implantation) | Absent |
| Infection risk | Moderate to high | Moderate | Very low (no pocket or leads) |
| Pocket erosion / hematoma | Possible | Possible | None |
| Tricuspid valve interference | Can worsen regurgitation | Less common | None |
| Battery longevity | ~6–10 years | ~6–10 years | ~10–15 years (depending on threshold) |
| Pacing threshold stability | Variable | His: unstableLBBAP: stable | Stable unless threshold rises (e.g., fibrosis) |
| Retrievability | Leads difficult to extract after fibrosis | Technically difficult | Some models retrievable (e.g., Aveir) |
| MRI compatibility | Conditional | Conditional | Conditional or full-body MRI-safe |
| Implantation complexity | Routine | More complex (especially His bundle) | Simple (percutaneous femoral or jugular) |
| Future potential | Limited | High for long-term preservation of LV function | Very high (next-gen: dual-chamber CSP systems) |
CSP offers the most physiologic pacing, protecting against long-term LV dysfunction.
Leadless systems eliminate hardware-related complications.
The future of pacing lies in combining both — CSP via a leadless platform, such as Abbott’s Aveir CSP, currently in clinical trials.
Would you like this as a printable PDF or HTML code version for your notes?