Biventricular or Conduction System Pacing for Cardiac Resynchronization Therapy: A Strategy for Cardiac Resynchronization Based on a Hybrid Approach

Abstract

Background: Cardiac resynchronization therapy (CRT) is usually performed with biventricular pacing (BiVP), but recently, conduction system pacing (CSP) has been proposed as an alternative in case of BiVP failure. The aim of this study is to define an algorithm to choose between BiVP and CSP resynchronization using the interventricular conduction delays (IVCD) as a guide. Methods: Consecutive patients from January 2018 to December 2020 with an indication for CRT were prospectively enrolled in the study group (delays-guided resynchronization group, DRG). A treatment algorithm based on IVCD was used to decide whether to leave the left ventricular (LV) lead to perform BiVP or pull it out and perform CSP. Outcomes from the DRG group were compared to a historical cohort of CRT patients who underwent CRT procedures between January 2016 and December 2017 (resynchronization standard guide group, SRG). The primary endpoint was a composite of cardiovascular mortality, heart failure (HF) hospitalization, or HF event at 1 year after the date of intervention. Results: The study population consisted of 292 patients, of which 160 (54.8%) were in the DRG and 132 (45.2%) in the SRG. In the DRG, 41 of 160 patients underwent CSP based on the treatment algorithm (25.6%). The primary endpoint was significantly higher in the SRG (48/132, 36.4%) compared to the DRG (35/160, 21.8%) (hazard ratio (HR): 1.72; 95% confidence interval (CI): 1.12–2.65; p = 0.013). Conclusions: A treatment algorithm based on IVCD shifted one patient out of every four from BiVP to CSP, with consequent reduction in the primary endpoint after implantation. Therefore, its application could be useful to determine whether to perform BiVP or CSP.

The interventricular conduction delays guide best cardiac resynchronization therapy: A tailored-patient approach to perform a CRT through Conduction System Pacing

“…LBBP seems to have better electrical parameters compared to HBP and a wider target area for implantation. The use of intracardiac conduction intervals to predict CRT response has already been described [ 2 , 3 ]. The IVCD and the wide QRS obtained with BiVP exposed the high probability of being non-responder to CRT [ 6 ].…”

“…The IVCD is an interesting, feasible and effective measure to choose the best CRT approach. The use of the IVCD to determine when to perform CSP in patients indicated for standard CRT resulted in a significant increase in the number of responders as reported in a recent paper [ 3 ]. In case of a conduction delay <100 ms, the application of the CSP therapy led to improved cardiac resynchronization when compared to patients with a similar conduction delay but treated with standard BiVP [ 3 ].…”

“…Conduction system pacing (CSP) has been demonstrated to be feasible and effective for a more physiological pacing on the natural conduction system. BiVP remains the first-line therapy for CRT, but, as suggested by European Guidelines, CSP should be considered in case of failed LV lead positioning [ 1 ] or in case of low value of IVCD [ 3 ]. Despite its physiological pacing, the HBP approach presented some drawbacks.…”