How to Implant Cardiac Resynchronization Therapy in a Busy Clinical Practice

Effects of adaptive left bundle branch-optimized cardiac resynchronization therapy: a single centre experience

BACKGROUND

Adaptive cardiac resynchronization therapy (aCRT) is associated with improved clinical outcomes. Left bundle branch area pacing (LBBAP) has shown encouraging results as an alternative option for aCRT. A technique that can be accomplished effectively using LBBAP combined with coronary venous pacing (LOT-aCRT). We aimed to assess the feasibility and outcomes of LOT-aCRT.

METHODS

LOT-aCRT, capable of providing two pacing modes, LBBAP alone or LBBAP combined with LV pacing, was attempted in patients with CRT indications. Patients were divided into two groups: those with LBBAP and LV pacing (LOT-aCRT) and those with conventional biventricular pacing (BVP-aCRT).

RESULTS

A total of 21 patients were enrolled in the study (10 in the LOT-aCRT group, 11 in the BVP-aCRT group). In the LOT-aCRT group, the QRS duration (QRSd) via BVP was narrowed from 158.0 ± 13.0 ms at baseline to 132.0 ± 4.5 ms (P = 0.019) during the procedure, and further narrowed to 123.0 ± 5.7 ms (P < 0.01) via LBBAP. After the procedure, when LOT-aCRT implanted and worked, QRSd was further changed to 121.0 ± 3.8 ms, but the change was not significant (P > 0.05). In the BVP-aCRT group, BVP resulted in a significant reduction in the QRSd from 176.7 ± 19.7 ms at baseline to 133.3 ± 8.2 ms (P = 0.011). However, compared with LOT-aCRT, BVP has no advantage in reducing QRSd and the difference was statistically significant (P < 0.01). During 9 months of follow-up, patients in both groups showed improvements in the LVEF and NT-proBNP levels (all P < 0.01). However, compared with BVP-aCRT, LOT-aCRT showed more significant changes in these parameters (P < 0.01).

CONCLUSIONS

The study demonstrates that LOT-aCRT is clinically feasible in patients with systolic heart failure and LBBB. LOT-aCRT was associated with significant narrowing of the QRSd and improvement in LV function.

Left ventricular lead placement using inner guiding catheter alone in cardiac resynchronization therapy device implantation

BACKGROUND

Subselection inner catheters (Inner-Cath) are used adjunctively with outer guiding catheters (Outer-Cath) during cardiac resynchronization therapy (CRT) device implantation. This study aims to investigate the feasibility and efficacy of left ventricular lead placement (LV-LP) guided by Inner-Cath alone.

METHODS

A total of 74 patients undergoing de novo CRT implantation were investigated. LV-LP was initially guided by Inner-Cath in 42 patients (Inner-Cath group) and Outer-Cath in 32 patients (Outer-Cath group). In the Inner-Cath group, a 7Fr Inner-Cath was advanced to the coronary sinus through a 7 Fr sheath inserted in a subclavian vein. In the Outer-Cath group, 9Fr or 10Fr Outer-Caths were used. Success rate of LV-LP, additional use of inner or outer catheters and procedure-related complications were compared between groups.

RESULTS

LV-LP was successful in all patients in the Inner-Cath group, while LV-LP had to be abandoned in two patients (6.3%) of the Outer-Cath group due to CS perforation caused by Outer-Cath manipulation. Procedure time was significantly shorter in the Inner-Cath group (148 vs. 168 min; p = .024). Deployment of both an inner and outer cath became necessary less frequently for the Inner-Cath group (4.8% vs. 56.3%; p < .001). Mechanical CS injuries due to guiding catheter manipulation were only observed in the Outer-Cath group (0% vs. 15.6%, p = .013).

CONCLUSION

LV-LP guided by Inner-Cath alone was feasible in over 95% of the patients without severe complications. This methodology for LV-LP may be preferable in CRT candidates with severe LV dysfunction in terms of shorter procedure time, smaller guiding sheath, and less procedure-related complications.