Alternative Techniques for Left Ventricular Pacing in Cardiac Resynchronization Therapy

A case report of left ventricular lead implantation via total three-dimensional transseptal puncture after tricuspid valve replacement

Background

Ventricular lead implantation is relatively difficult for patients with bradyarrhythmia after tricuspid valve replacement. Right atrial (RA) abnormalities often occurred in patients with tricuspid valve disease; conventional coronary sinus (CS) lead implantation is not easy to operate. Therefore, it is necessary to develop a safe method for implanting LV endocardial leads in patients after tricuspid valve replacement.

Case presentation

A 76-year-old Asian woman who had been implanted with a metal tricuspid valve replacement 4 years ago was admitted to the Department of Cardiology for pacemaker implantation due to transient blackout related to persistent atrial fibrillation with long pauses. The patient's family rejected the surgical placement of an epicardial LV lead. Therefore, we first intended to operate LV lead implantation through the CS; however, the orifice of the CS was virtually difficult to seek. Ultimately, we utilized total 3-dimensional (T3D) transseptal puncture (TSP) under the guidance of the CARTO 3 system; thus, we implanted the LV endocardial lead, which contributed to the accurate puncture of the central fossa ovalis and ensured the safety of TSP in the case of RA enlargement. Meanwhile, the CARTO 3 system contributed to the localization of the LV lead to the LV free wall during implantation. All the intraoperative and postoperative pacemaker parameters were favorable; no intraoperative or postoperative complications occurred.

Conclusions

This case report may provide a novel surgical approach for LV lead implantation in patients who underwent tricuspid valve replacement or patients who may benefit from cardiac resynchronization therapy but failed to implant CS lead.

Video-assisted thoracoscopic epicardial pacing: A contemporary overview

Video-assisted thoracoscopic surgery (VATS) has revolutionized the approach and management of pulmonary and cardiac diseases, and its applications have significantly expanded in the last two decades. Beyond its established role in thoracic procedures, VATS has also emerged as a valuable technique for various electrophysiological procedures, including pacemaker implantations, ablation procedures, and left atrial appendage exclusion. This paper presents a thorough review of the existing literature on pacing procedures performed using a VATS approach. By analyzing and synthesizing the available studies, we aim to provide an in-depth understanding of the current knowledge and advancements in VATS-based pacing procedures. A key focus of this review is the detailed description of implantation techniques via a VATS approach.

The impacts of preoperative frailty on readmission after cardiac implantable electrical device implantation

Cardiac implantable electrical devices (CIED) such as pacemakers, implantable cardioverter defibrillators, and cardiac resynchronization therapies are generally recommended for older patients and those with severe heart failure (HF). However, there is currently a lack of evidence on the relationship between frailty and readmission rates among patients with CIED. This study investigated whether preoperative frailty influenced readmission rates among patients with CIED over a one-year period following implantation. The study retrospectively analyzed 101 patients who underwent CIED implantations. To compare frailty-based differences in their characteristics and readmission rates, these participants were categorized into frailty and non-frailty groups via the modified frailty index (mFI). The frailty group had a significantly higher readmission rate than the non-frailty group (non-frailty group vs. frailty group = 1 vs. 8 patients: P < 0.05). Further, a multivariate analysis showed that frailty was a significant readmission factor. Based on individual analyses with/without histories of HF, the readmission rate also tended to be higher among individuals considered frail via the mFI (readmission rate in HF patients: non-frailty group vs. frailty group = 1 vs. 5 patients: P = 0.65; non-HF patients: non-frailty group vs. frailty group = 0 vs. 3 patients: P = 0.01). Participants with preoperative frailty showed higher readmission rates within a one-year period following implantation compared to those without preoperative frailty. This tendency was consistent regardless of HF history. The mFI may thus help predict readmission among patients with CIED.

A Novel Approach for Repetitive Dislocation of Transvenous Left Ventricular Leads During Cardiac Resynchronization Therapy Implantation by the Loop Technique

Cardiac resynchronization therapy (CRT) for heart failure requires transvenous insertion of a left ventricular pacing lead through the coronary sinus. However, repeated intraoperative dislocations often occur. Therefore, we describe a novel technique that uses the loop technique to treat patients with repeated intraoperative dislocations during transvenous left ventricular lead implantation to stabilize the lead in its final position. In five patients with repeated intraoperative dislocation during transvenous left ventricular lead implantation, the loop technique was successfully used to stabilize the lead in its final position. The pacing and sensing parameters were satisfactory in all patients at implantation and 12 months post-operatively. Compared with the pre-operative values, the 12-month post-operative values for the left ventricular ejection fraction were significantly increased and the left ventricular end systolic dimension and left ventricular end diastolic dimension were significantly decreased (P < 0.05). The left ventricular ejection fraction of these 5 patients increased by more than 15%. CRT significantly improved the left ventricular structure and function of these 5 patients. During the 1-, 3-, 6-, and 12-month follow-ups, no left ventricular lead dislocations were observed. This loop technique is safe and effective and can be considered for repeated intraoperative dislocation during transvenous left ventricular lead implantation through the coronary sinus of a CRT device.

Comparative efficacy of image-guided techniques in cardiac resynchronization therapy: a meta-analysis

Background

Several studies have illustrated the use of echocardiography, magnetic resonance imaging, and nuclear imaging to optimize left ventricular (LV) lead placement to enhance the response of cardiac resynchronization therapy (CRT) in heart failure patients. We aimed to conduct a meta-analysis to determine the incremental efficacy of image-guided CRT over standard CRT.

Methods

We searched PubMed, Cochrane library, and EMBASE to identify relevant studies. The outcome measures of cardiac function and clinical outcomes were CRT response, concordance of the LV lead to the latest sites of contraction (concordance of LV), heart failure (HF) hospitalization, mortality rates, changes of left ventricular ejection fraction (LVEF), and left ventricular end-systolic volume (LVESV).

Results

The study population comprised 1075 patients from eight studies. 544 patients underwent image-guided CRT implantation and 531 underwent routine implantation without imaging guidance. The image-guided group had a significantly higher CRT response and more on-target LV lead placement than the control group (RR, 1.33 [95% CI, 1.21 to 1.47]; p < 0.01 and RR, 1.39 [95% CI, 1.01 to 1.92]; p < 0.05, respectively). The reduction of LVESV in the image-guided group was significantly greater than that in the control group (weighted mean difference, − 12.46 [95% CI, − 18.89 to − 6.03]; p < 0.01). The improvement in LVEF was significantly higher in the image-guided group (weighted mean difference, 3.25 [95% CI, 1.80 to 4.70]; p < 0.01). Pooled data demonstrated no significant difference in HF hospitalization and mortality rates between two groups (RR, 0.89 [95% CI, 0.16 to 5.08]; p = 0.90, RR, 0.69 [95% CI, 0.37 to 1.29]; p = 0.24, respectively).

Conclusions

This meta-analysis indicates that image-guided CRT is correlated with improved CRT volumetric response and cardiac function in heart failure patients but not with lower hospitalization or mortality rate.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12872-021-02061-y.

Epicardial left ventricular lead implantation in cardiac resynchronization therapy patients via a video-assisted thoracoscopic technique: Long-term outcome

BACKGROUND

Epicardial placement of the left ventricular (LV) lead via a video-assisted thoracoscopic (VAT) approach is an alternative to the standard transvenous technique.

HYPOTHESIS

Long-term safety and efficacy of VAT and transvenous LV lead implantation are comparable. To test it, we reviewed our experience and we compared the outcomes of patients who underwent implantation with the two techniques.

METHODS

The VAT procedure is performed under general anesthesia, with oro-tracheal intubation and right-sided ventilation, and requires two 5 mm and one 15 mm thoracoscopic ports. After pericardiotomy at the spot of the epicardial target area, pacing measurements are taken and a spiral screw electrode is anchored at the final pacing site. The electrode is then tunneled to the pectoral pocket and connected to the device.

RESULTS

105 patients were referred to our center for epicardial LV lead implantation. After pre-operative assessment, 5 patients were excluded because of concomitant conditions precluding surgery. The remaining 100 underwent the procedure. LV lead implantation was successful in all patients (median pacing threshold 0.8 ± 0.5 V, no phrenic nerve stimulation) and cardiac resynchronization therapy was established in all but one patient. The median procedure time was 75 min. During a median follow-up of 24 months, there were no differences in terms of death, cardiovascular hospitalizations or device-related complications vs the group of 100 patients who had undergone transvenous implantation. Patients of both groups displayed similar improvements in terms of ventricular reverse remodeling and functional status.

CONCLUSIONS

Our VAT approach proved safe and effective, and is a viable alternative in the case of failed transvenous LV implantation.

Leadless pacing

Leadless self-contained intracardiac pacemakers were developed with the aim of abolishing the short- and long-term risk of lead- and pocket-related complications associated with transvenous devices. Leadless pacemakers promise minimally invasive procedures, long battery lives, and small amounts of foreign materials in the body. Experiences with the pioneering single-chamber devices have provided reasons for optimism about the future of the leadless concept. In the future, as more patients receive and live longer with implantable devices, the total risk of procedure- and lead-related complications is expected to increase, adding a sense of urgency to the need for leadless alternatives to transvenous pacemakers. This review surveys the performance of currently available leadless pacemakers as well as emerging new innovative adaptations and applications of the leadless concept.

Dual-site right ventricular pacing in patients undergoing cardiac resynchronization therapy: Results of a multicenter propensity-matched analysis

BACKGROUND

Dual-site right ventricular pacing (Dual RV) has been proposed as an alternative for patients with heart failure undergoing cardiac resynchronization therapy (CRT) with a failure to deliver a coronary sinus (CS) lead. Only short-term hemodynamic and echocardiographic results of Dual RV are available. We aimed to assess the long-term results of Dual RV and its impact on survival.

METHODS

Multicenter retrospective assessment of all CRT implants during a 12-year period. Patients with failed CS lead implantation, treated with Dual RV, were followed and assessed for the primary endpoint of all-cause mortality and/or heart transplant. A control group was obtained from contemporary patients using propensity matching for all available baseline variables.

RESULTS

Ninety-three patients were implanted with Dual RV devices and compared with 93 matched controls. During a median of 1,273 days (interquartile range 557-2,218), intention-to-treat analysis showed that all-cause mortality and/or heart transplant was higher in the Dual RV group (adjusted hazard ratio [HR] = 1.66, 95% confidence interval [CI] 1.12-2.47, P = 0.012). As-treated analysis yielded similar results (HR = 1.97, 95% CI 1.31-2.96, P = 0.001). Cardiac device-related infections occurred seven times more frequently in the Dual RV site group (HR = 7.60, 95% CI 1.51-38.33, P = 0.014). Among Dual RV nonresponders, four had their apical leads switched off, five required an epicardial LV lead insertion, a transseptal LV lead was implanted in two, and in nine patients, after reviewing the CS venogram, a new CS lead insertion was successfully attempted.

CONCLUSION

Dual RV pacing is associated with worse clinical outcomes and higher complication rates than conventional CRT.

Transvenous versus open chest lead placement for resynchronization therapy in patients with heart failure: comparison of ventricular electromechanical synchronicity

Background

Transvenous lead placement is the standard approach for left ventricular (LV) pacing in cardiac resynchronization therapy (CRT), while the open chest access epicardial lead placement is currently the most frequently used second choice. Our study aimed to compare the ventricular electromechanical synchronicity in patients with heart failure after CRT with these two different LV pacing techniques.

Methods

We enrolled 33 consecutive patients with refractory heart failure secondly to dilated cardiomyopathy who were eligible for CRT in this study. Nineteen patients received transvenous (TV group) while 14 received open chest (OP group) LV lead pacing. Intra- and inter-ventricular electromechanical synchronicity was assessed by tissue Doppler imaging (TDI) before and one year after CRT procedure.

Results

Before CRT procedure, the mean QRS-duration, maximum time difference to systolic peak velocity among 12 left ventricle segments (LV Ts-12), standard deviation of time difference to systolic peak velocity of 12 left ventricle segments (LV Ts-SD), and inter-ventricular mechanical delay (IVMD) in OP and TV group were 166 ± 17 ms and 170 ± 21 ms, 391 ± 42 ms and 397 ± 36 ms, 144 ± 30 ms and 148 ± 22 ms, 58 ± 25 ms and 60 ± 36 ms, respectively (all P > 0.05). At one year after the CRT, the mean QRS-duration, LV Ts-12, LV Ts-SD, and IVMD in TV and OP group were 128 ± 14 ms and 141 ± 22 ms (P = 0.031), 136 ± 37 ms and 294 ± 119 ms (P = 0.023), 50 ± 22 ms and 96 ± 34 ms (P = 0.015), 27 ± 11 ms and 27 ± 26 ms (P = 0.86), respectively. The LV lead implantation procedure time was 53.4 ± 16.3 min for OP group and 136 ± 35.1 min for TV group (P = 0.016). The mean LV pacing threshold increased significantly from 1.7 ± 0.6 V/0.5 ms to 2.3 ± 1.6 V/0.5 ms (P < 0.05) in TV group while it remained stable in the OP group.

Conclusions

Compared to conventional endovascular approach, open chest access of LV pacing for CRT leads to better improvement of the intraventricular synchronization.

Robotic-Assisted Left Ventricular Lead Placement

Robot-assisted left ventricular lead implantation for cardiac resynchronization therapy is a feasible and safe technique with superior visualization, dexterity, and precision to target the optimal pacing site. The technique has been associated with clinical response and beneficial reverse remodeling comparable with the conventional approach via the coronary sinus. The lack of clinical superiority and a residual high nonresponder rate suggest that the appropriate clinical role for the technique remains as rescue therapy.

Long-Term Follow-Up of Isolated Epicardial Left Ventricular Lead Implant Using a Minithoracotomy Approach for Cardiac Resynchronization Therapy

BACKGROUND

Transvenous left ventricular (LV) lead placement for cardiac resynchronization therapy is unsuccessful in 5-10% of reported cases. These patients may benefit from isolated surgical placement of an epicardial LV lead via minithoracotomy approach.

AIM

To evaluate the success of this approach at long-term follow-up.

METHODS

Retrospective evaluation of all consecutive patients undergoing isolated epicardial LV lead placement after failed transvenous attempt over a 6-year period. Data collected on baseline parameters, procedural details, and outcome at follow-up (hospital stay, complications, mortality, and clinical response).

RESULTS

Forty-two patients underwent epicardial lead implant. Five died within 1 year (11.9%): two (4.8%) died within 30-days post op (one from intraoperative hemorrhage, the other from multiple organ failure); 39 (95.1%) were admitted to the high dependency unit and transferred to the ward <24 hours. Median hospital stay was 3.4 ± 1.9 days. The overall complication rate was 17.5% (n = 7): 15.0% (n = 6) short term and 2.5% (n = 1) long term; these included three (7.5%) LV noncapture events all treated with reprogramming. There were two (5.0%) wound infections requiring oral antibiotics and two (5.0%) device infections requiring intravenous antibiotics (one had device resiting, the other developed septic shock requiring intensive care admission). Assessment of clinical response was possible in 34 (81.0%) at follow-up: 21 (61.8%) were responders and 13 (28.2%) nonresponders with no significant differences between these groups; no clinical predictors of response were identified.

CONCLUSION

Isolated epicardial LV lead implant using minithoracotomy is relatively safe and effective at successful LV pacing. Response rate and postoperative recovery at long-term follow-up are reasonable in these high-risk patients.

Robotic-Assisted Left Ventricular Lead Placement

Robot-assisted left ventricular lead implantation for cardiac resynchronization therapy is a feasible and safe technique with superior visualization, dexterity, and precision to target the optimal pacing site. The technique has been associated with clinical response and beneficial reverse remodeling comparable with the conventional approach via the coronary sinus. The lack of clinical superiority and a residual high nonresponder rate suggest that the appropriate clinical role for the technique remains as rescue therapy.