The Use of Quadripolar Left Ventricular Leads Improves the Hemodynamic Response to Cardiac Resynchronization Therapy

Long-Term Performance of Epicardial versus Transvenous Left Ventricular Leads for Cardiac Resynchronization Therapy

Aims: to study the technical performance of epicardial left ventricular (LV) leads placed via video assisted thoracic surgery (VATS), compared to transvenously placed leads for cardiac resynchronization therapy (CRT). Methods: From 2001 until 2013, a total of 644 lead placement procedures were performed for CRT. In the case of unsuccessful transvenous LV lead placement, the patient received an epicardial LV lead. Study groups consist of 578 patients with a transvenous LV lead and 66 with an epicardial LV lead. The primary endpoint was LV-lead failure necessitating a replacement or deactivation. The secondary endpoint was energy consumption. Results: The mean follow up was 5.9 years (epicardial: 5.5 ± 3.1, transvenous: 5.9 ± 3.5). Transvenous leads failed significantly more frequently than epicardial leads with a total of 66 (11%) in the transvenous leads group vs. 2 (3%) in the epicardial lead group (p = 0.037). Lead energy consumption was not significantly different between groups. Conclusions: Epicardial lead placement is feasible, safe and shows excellent long-term performance compared to transvenous leads. Epicardial lead placement should be considered when primary transvenous lead placement fails or as a primary lead placement strategy in challenging cases.

Cardiac resynchronization therapy setting personalization utilizing noninvasive hemodynamics

BACKGROUND

Cardiac resynchronization therapy (CRT) has been an important adjunct to goal directed medical therapy in heart failure patients who qualify for this device. Too often, when heart failure patients complain about severe fatigue, beta-blockers are immediately reduced. Personalization of settings, verified by noninvasive hemodynamics, can allow for maximizing medical therapy.

CASE

A newly diagnosed 40 year-old male presented to the heart failure clinic post hospital discharge with a severely dilated, non-ischemic cardiomyopathy. Even with an ejection fraction (EF) of 15-20%, he reports "feeling great". Increasing medications resulted in excessive fatigue. Non-invasive studies showed an average cardiac index (CI) of 1.5l/min/m². It was decided to personalize his settings. Changes made increased his CI to 3.9l/min/m².

CONCLUSION

Combining current available technology with noninvasive studies significantly improved his CI and no reduction in beta-blocker therapy was necessary. CRT personalization can be of significant value for the heart failure patient.

Clinical outcome of left ventricular multipoint pacing versus conventional biventricular pacing in cardiac resynchronization therapy: a systematic review and meta-analysis

Cardiac resynchronization therapy (CRT) is an effective treatment for selected patients with systolic heart failure. Unlike conventional biventricular pacing (BIP), the left ventricular multipoint pacing (MPP) can increase the number of left ventricular pacing sites via a quadripolar lead positioned in the coronary sinus. This synthetic study was conducted to integratively and quantitatively evaluate the clinical outcome of MPP in comparison with BIP. We systematically searched the databases of EMBASE, Ovid medline, and Cochrane Library through May 2018 for studies comparing the clinical outcome of MPP with BIP in the patients who accepted CRT. Hospitalization for reason of heart failure, left ventricular eject fraction (LVEF), CRT response, all-cause morbidity, and cardiovascular death rate was collected for meta-analysis. A total of 11 studies with 29,606 participants were included in this meta-analysis. Compared with BIP group, MPP decreased heart failure hospitalization (OR, 0.41; 95% CI, 0.33 to 0.50; P < 0.00001), improved LVEF (mean difference, 4.97; 95% CI, 3.11 to 6.83; P < 0.00001), increased CRT response (OR, 3.64; 95% CI, 1.68 to 7.87; P = 0.001), and decreased all-cause morbidity (OR, 0.41; 95% CI, 0.26-0.66; P = 0.0002) and cardiovascular death rate (OR, 0.21; 95% CI, 0.11-0.40; P < 0.00001). The published literature demonstrates that MPP was more effective than BIP in the heart failure patients who accepted cardiac resynchronization therapy.

Combination of the best pacing configuration and atrioventricular and interventricular delays optimization in cardiac resynchronization therapy

BACKGROUND

Cardiac resynchronization therapy optimization can be pursued by left ventricular pacing vector selection and atrioventricular (AV) and interventricular (VV) delays optimization. The combination of these methods and its comparison with multipoint pacing (MPP) is scarcely studied.

METHODS

Using noninvasive cardiac output (CO) measurement, the best of five left ventricular pacing vectors was determined, then AV and VV delays optimization was applied on top of the best vector. Response to the optimization protocol was defined as a >5% CO increase compared to the standard biventricular configuration.

RESULTS

Twenty-two patients (18 men, age 71 ± 9 years) were included. Standard biventricular configuration increased CO compared to baseline (4.65 ± 1.55 L/min vs 4.27 ± 1.53 L/min, respectively, P = 0.02). The best quadripolar configuration increased CO to 4.85 ± 1.67 L/min (P = 0.03 compared to the standard biventricular configuration). AV then VV delay optimization both provided additional benefit (final CO 5.56 ± 2.03 L/min, P = 0.001 compared to the best quadripolar configuration). Fifteen (68%) patients responded to the optimization protocol. Anatomical MPP (based on maximal anatomical separation between electrodes) and electrical MPP (based on maximal electrical activation difference between electrodes) were evaluated in 16 patients and yielded a CO similar to that of the optimization procedure.

CONCLUSIONS

The combination of choosing the best quadripolar pacing configuration and optimizing atrioventricular and interventricular delays resulted in an improvement of cardiac output compared to standard biventricular stimulation in 68% of patients. The final cardiac output was comparable to multipoint pacing.

Repetitive optimizing left ventricular pacing configurations with quadripolar leads improves response to cardiac resynchronization therapy: A single-center randomized clinical trial

BACKGROUND

This study aimed to investigate whether repetitive optimizing left ventricular pacing configurations (LVPCs) with quadripolar leads (QUAD) can improve response to cardiac resynchronization therapy (CRT).

METHODS

Fifty-two eligible patients were enrolled and 1:1 randomized to either the quadripolar LV leads (QUAD) group or the conventional bipolar leads (CONV) group. In the QUAD group, optimization of LVPC was performed for all patients before discharge and for nonresponders at 3 months follow-up. Clinical evaluations and transthoracic echocardiograms were performed before, 3, and 6 months after CRT implantation.

RESULTS

At 3 months follow-up, 16 of 25 (64%) patients in the CONV group (1 patient was lost to follow-up) and 18 of 26 (69%) patients in the QUAD group were classified as responders. After optimizing the LVPCs in 3-month nonresponders in the QUAD group, 21 of 26 (80.8%) patients in the QUAD group were classified as responders at 6 months as compared with 17 of 25 (68%) patients in the CONV group. Left ventricular end-systolic volume (LVESV) reduction, left ventricular ejection fraction (LVEF) increase, and New York Heart Association (NYHA) functional class reduction at 6 months were significantly greater in the QUAD group than in the CONV group (LVESV: -26.9 ± 13.8 vs -17.2 ± 13.3%; P = .013; LVEF: +12.7 ± 8.0 vs +7.8 ± 6.3 percentage points; P = .017; NYHA: -1.27 ± 0.67 vs -0.72 ± 0.54 functional classes; P = .002).

CONCLUSIONS

Compared with conventional bipolar leads, CRT using quadripolar leads with repetitive optimized LVPCs resulted in an additional increase in LVEF and reduction in LVESV and NYHA functional class at 6-month follow-up.

Short-Term Availability of Viable Left Ventricular Pacing Sites with Quartet™ Quadripolar Leads

BACKGROUND Whether quadripolar leads can provide sufficient viable left ventricular pacing sites (LVPSs) for device optimization and multipoint pacing remains unclear. This study aimed to evaluate the acute and 3-month availability of viable LVPSs provided by a quadripolar LV pacing lead. MATERIAL AND METHODS A single-center cohort study evaluated consecutive patients who underwent a CRT implant with the QuartetTM LV lead under local guidelines. The availability of viable LVPSs was assessed at the pre-discharge and 3-month follow-up visit. Bipolar lead configurations, which served as the control group, were modeled by eliminating the 2 proximal electrodes on the Quartet™ LV lead. RESULTS A total of 24 patients were enrolled and finished 3-month follow-up. The mean follow-up period was 93±3 days. At pre-discharge, the Quartet™ LV lead provided more viable LVPSs compared with the bipolar equivalents (median 3 [IQR 2-4] vs. median 2 [IQR 1-2], P<0.001). The percentage of patients with at least 1, 2, 3, and 4 viable LVPSs were 100% (24/24), 91.7% (22/24), 58.3% (14/24), and 33.3% (8/24) for Quartet™ leads and 91.7% (22/24), 70.8% (17/24), 0% (0/24), and 0% (0/24) for bipolar lead configurations, respectively. The median and IQR values of viable LVPSs provided by the Quartet™ LV lead remained the same (3 [IQR 2-4]) between pre-discharge and 3-month follow-up (P=0.45). CONCLUSIONS Compared with the bipolar equivalent, QuartetTM LV lead provides more viable LVPSs and opportunities for CRT optimization and multipoint LV pacing. The number of LVPSs provided by Quartet™ leads remained unchanged between pre-discharge and 3-month follow-up.

Haemodynamic Alterations Induced By Cardiac Pacing: Is Clinical Evaluation Sufficient Or Do We Need Long-Term Device Monitoring?

Cardiac pacing may induce haemodynamic alterations. RV pacing may have deleterious effects including a decrease of LV function as well as an increase of heart failure hospitalizations and mortality. Biventricular pacing is established in patients with heart failure and left bundle branch block or chronic AV block to improve haemodynamics. In the future, device optimization employing quadripolar leads or multisite pacing may further increase the rate of responders. However, cinical evaluation represents the most important tool to recognize the necessity for device optimization. Device algorithms are not yet successfully established to replace clinical and echocardiographic evaluation.

Safety, feasibility, and outcome results of cardiac resynchronization with triple-site ventricular stimulation compared to conventional cardiac resynchronization

BACKGROUND

The nonresponder rate to cardiac resynchronization therapy (CRT) may be due to incomplete resynchronization, with dyssynchrony persisting in approximately 30% of patients. We hypothesized that CRT with triple-site ventricular stimulation (TRIV) may improve resynchronization and its outcomes.

OBJECTIVE

The purpose of this study was to assess the feasibility and safety of TRIV and collected data on clinical outcomes to dimension future studies.

METHODS

Our pilot randomized trial was designed to assess the safety and feasibility of TRIV with 2 right ventricular leads and 1 left ventricular leads compared to conventional CRT. The primary end-point was the rate of severe adverse events at 6 months. Secondary end-points included functional improvement parameters, quality-of-life (QOL) score, and changes of echocardiographic indices at 6 and 12 months in a subset of patients.

RESULTS

Seventy-six patients were enrolled at 11 centers and randomized to control or TRIV arm. All implant procedures but one were successful. At 6 months, there was no statistical difference between proportions of patients with at least 1 severe adverse event in both groups (34.1% vs 25.7%, P = .425). There also was no difference between functional improvement parameters, 6-minute walking distances (P = .40), QOL scores (P = .27), and echographic indices. At 12 months, the proportions of patients with a left ventricular ejection fraction gain of more than 5%, 10%, or 15% were significantly superior with TRIV.

CONCLUSION

TRIV pacing is an effective and safe technique and may provide a greater benefit in ventricular remodeling than conventional CRT. Further studies are needed to assess its long-term benefit.