Achieving narrow QRS without LV lead in Heart Failure

jipmer.jpg

Raja Selvaraj, JIPMER

Introduction

Resynchronization without LV lead

  • Resynchronization therapy works in patients with LBBB and heart failure
  • Sometimes alternative needed
    • Inability to obtain good LV lead placement - anatomical / phrenic nerve pacing - 10%
    • Non response to BiV pacing - ? 30%
    • Other forms of dyssynchrony - RBBB
    • Superior alternative can become primary approach

LV lead alternatives for cardiac resynchronization

  • Septal pacing
  • Multisite RV pacing
  • His bundle pacing

Septal pacing

Septal pacing

  • Active fixation lead placed in septal RVOT / mid IVS
  • Technically not very difficult, no additional cost
  • Most studies compared with RVA pacing
  • Some data on CRT alternative

Septal pacing

rvot1.jpg

Septal pacing

rvot2.jpg

Septal pacing - QRS duration

septal1.png

Hafez A. Alhous et al. Right ventricular septal pacing as alternative for failed left ventricular lead implantation in cardiac resynchronization therapy candidates. EP Europace, Volume 17, Issue 1, 1 January 2015, Pages 94–100

Septal pacing - Acute hemodynamics

septal2.png

Hafez A. Alhous et al. Right ventricular septal pacing as alternative for failed left ventricular lead implantation in cardiac resynchronization therapy candidates. EP Europace, Volume 17, Issue 1, 1 January 2015, Pages 94–100

Bifocal pacing

RV bifocal pacing

  • Pacing in RV apex and RVOT
  • Better synchrony than RVA pacing
  • Alternative to CRT ?
  • Could be better in RBBB patients ?

Bifocal pacing

bifocal.jpg

José Carlos Pachón Mateos et al. Right Ventricular Bifocal Stimulation in the Treatment of Dilated Cardiomyopathy with Heart Failure. Arq. Bras. Cardiol. vol.73 n.6 São Paulo Dec. 1999

BRIGHT study

bright.png

Jan C.J. Res et al. The BRIGHT study: bifocal right ventricular resynchronization therapy: a randomized study. Europace (2007) 9, 857–861

HBP

Rationale

  • Recruitment of bundle branches in those with block
  • Longitudinal dissociation
  • Theoretically ideal form of resynchronization
  • Even better resynchronization in non LBBB forms of wide QRS

Rationale

hbp.png

Example

hbp_example.jpg

from Pugazhendi Vijayaraman

HBP for failed CRT

  • 16 patients with failed CRT (14% of all CRTs)
  • Temporary HB pacing corrected BBB in 13 (81%)
  • Successful permanent HBP in 9 (69%)
  • Improvement in NYHA class, LVEF and LV dimensions

Barba-Pichardo Rafael et al. Ventricular resynchronization therapy by direct His-bundle pacing using an internal cardioverter defibrillator. Europace. 2013 Jan;15 (1):83–8.

HBP in lieu of CRT

  • 21 patients with indication for CRT
  • HBP instead of LV lead
  • Successful lead placement in 16
  • QRS narrowing in 76%
  • CHF improvement, LV remodeling
  • Not compared to LV lead

Ajijola, Olujimi A… Kalyanam Shivkumar. Permanent His-bundle pacing for cardiac resynchronization therapy: Initial feasibility study in lieu of left ventricular lead. Heart Rhythm 2017; 14(9), 1353 - 1361

HBP after AVN ablation

  • 52 patients with AF and heart failure
  • AVN ablation
  • Permanent HBP in 42 patients (81%)
  • QRS width same as intrinsic
  • Significant clinical and echocardiographic improvement

Huang W et al. Benefits of Permanent His Bundle Pacing Combined With Atrioventricular Node Ablation in Atrial Fibrillation Patients With Heart Failure With Both Preserved and Reduced Left Ventricular Ejection Fraction. Journal of the American Heart Association. 2017;6:e005309

Summary

Summary - CRT

  • CRT is the gold standard for resynchronization
  • Technically gets easier by the day
  • Non responder rates not as high as suggested by literature

Summary - Septal / bifocal pacing

  • Septal pacing
    • Perhaps should replace apical pacing
    • But clearly inferior to CRT
  • Bifocal pacing
    • Could be considered in failed CRT if epicardial lead cannot be done
    • Less efficacy than CRT
    • Needs to be studied in RBBB / LV dysfunction

Summary - LVEP

  • LV endocardial pacing
  • Novel lead delivery systems (1)
  • Alternative method of pacing LV when CS lead placement fails

Morgan JM, Biffi M et al; ALSYNC Investigators. ALternate Site Cardiac ResYNChronization (ALSYNC): a prospective and multicentre study of left ventricular endocardial pacing for cardiac resynchronization therapy. Eur Heart J. 2016 Jul 14;37(27):2118-27

Summary - His bundle pacing

  • Theoretically HBP should be equivalent or better than BiV, but no RCT
  • Still evolving
  • Limitations
    • Achieving reliable permanent HBP
    • High thresholds
    • Sensing issues (small R wave, P wave)
    • Damage to His bundle ?