Performance of a novel active fixation quadripolar left ventricular lead for cardiac resynchronization therapy: Attain Stability Quad Clinical Study results

Rationale and Design of the Personalized Therapy Study: Evaluating Real-World Performance of Two Automated Defibrillation Therapy Algorithms

BACKGROUND

Barriers to maximizing patient benefit with implantable defibrillation devices include limited ability to tailor antitachycardia pacing (ATP) therapy in real time and identify patients at risk of heart failure (HF) events early on. The Personalized Therapy study aims to evaluate the performance of 2 algorithms, intrinsic ATP (iATP) and TriageHF, to address these barriers in routine clinical practice.

METHODS AND RESULTS

The Personalized Therapy Study was designed as a prospective, multicenter, post-market registry study expected to enroll approximately 2200 patients meeting the following criteria: (1) implanted with a study-eligible device regardless of procedure type, (2) Medtronic CareLink Network enrolled, (3) TriageHF enabled within CareLink and High-Risk Alert notifications turned ON, and (4) iATP enabled. The primary study objectives are to demonstrate iATP effectiveness in the fast ventricular tachycardia zone and estimate the positive predictive value of TriageHF high-risk status for worsening HF. Additionally, objectives include characterizing iATP effectiveness in all ventricular detection zones and characterizing TriageHF-based clinical actions and related HF hospitalizations.

CONCLUSION

This study is expected to generate real-world evidence on the performance of the iATP and TriageHF algorithms, which aim to improve clinical practice by tailoring arrhythmia and HF therapies to individual patient disease states.

Clinical Usefulness of the Active Fixation Quadripolar Left Ventricular Lead Compared With the Passive Fixation Quadripolar Lead in Cardiac Resynchronization Therapy

BACKGROUND

This study compared the stability of the Medtronic Attain Stability Quad (ASQ), a novel quadripolar active fixation left ventricular (LV) lead with a side helix, to that of conventional quadripolar leads with passive fixation (non-ASQ) and evaluated their LV lead performance.

METHODS AND RESULTS

In all, 183 consecutive patients (69 ASQ, 114 non-ASQ) who underwent cardiac resynchronization therapy (CRT) between January 2018 and June 2021 were enrolled. Complications, including elevated pacing capture threshold (PCT) levels, phrenic nerve stimulation (PNS), and LV lead dislodgement, were analyzed during the postimplantation period until the first outpatient visit after discharge. The frequency of LV lead-related complications was significantly lower in the ASQ than non-ASQ group (14% vs. 30%, respectively; P=0.019). Specifically, LV lead dislodgement occurred only in the non-ASQ group, and elevated PCT levels were significantly lower in the ASQ group (7% vs. 23%; P=0.007). Kaplan-Meier analysis confirmed a significantly lower incidence of LV lead-related complications in the ASQ group (log-rank P=0.005). Cox multivariable regression analysis showed a significant reduction in lead-related complications associated with ASQ (hazard ratio 0.44; 95% confidence interval 0.23-0.83; P=0.011).

CONCLUSIONS

The ASQ group exhibited fewer LV lead-related complications requiring reintervention and setting changes than the non-ASQ group. Thus, the ASQ may be a favorable choice for CRT device implantation.

Efficacy and safety of novel left ventricular pacing leads: 1-year analysis of the NAVIGATOR trial

OBJECTIVES

Assess safety and performance of novel quadripolar preshaped left ventricular (LV) leads: NAVIGO 4LV 2D ('S shaped') and NAVIGO 4LV ARC ('U shaped').

METHODS

Patients indicated for cardiac resynchronisation therapy were enrolled in a multicentre, prospective, controlled study (NAVIGATOR, NCT03279484). Patients were implanted with either a NAVIGO 4LV 2D or ARC lead, and assessed at 10 weeks, 6, 12 and 24 months post-implant. Co-primary safety and performance endpoints were assessed at 10 weeks. Safety endpoint was the patients' rate free from lead-related complications. Performance endpoint was the rate of patients with successful lead performance, defined as LV pacing threshold ≤2.5 V at 0.5 ms on at least one pacing vector, and the absence of phrenic nerve stimulation at the final programmed configuration. Lead-related complications and electrical parameters were monitored throughout study.

RESULTS

A NAVIGO 4LV lead was successfully implanted in 211 out of 217 patients (97.2%). The safety endpoint was met, with 100% and 96.1% of patients free from complications for NAVIGO 4LV 2D and ARC, respectively. The performance endpoint was met with 98.1% and 98.9% of patients with a successful lead performance for NAVIGO 4LV 2D and ARC, respectively. Over 12 months, the global complication-free rate for both leads was 97.1% (95% CI: 93.71% to 98.70%), with a mean pacing capture threshold of 1.23 V±0.73 V and a mean impedance of 951 Ω±300.1 Ω.

CONCLUSION

A high implantation success rate and low complication rate was reported for the novel NAVIGO 4LV 2D and ARC leads, along with successful performance up to 12 months.

Left ventricular lead implantation failure in an unselected nationwide cohort

BACKGROUND

Left ventricular (LV) lead implantation is often the most challenging aspect of cardiac resynchronization therapy (CRT) procedures; early studies reported implant failure rates in ∼10% of cases.

OBJECTIVE

The purpose of this study was to define rates, reasons for, and factors independently associated with LV lead implant failure.

METHODS

We studied patients with left bundle branch block and ejection fraction ≤ 35% who underwent planned de novo transvenous CRT implantation (2010-2016) and were reported to the National Cardiovascular Data Registry ICD Registry. Independent predictors of LV lead implant failure were determined using logistic regression; age, sex, and variables with a univariable P value of <.15 were considered for inclusion in the model.

RESULTS

Of the 111,802 patients who underwent a planned CRT procedure, 3.6% of patients (n = 3979) had LV lead implant failure. Reasons for implant failure included venous access (7.5%), coronary sinus access (64.3%), tributary vein access (13.5%), coronary sinus dissection (7.6%), unacceptable threshold (4.4%), and diaphragmatic stimulation (1.7%). Significant independent predictors of LV lead implant failure included younger age (odds ratio [OR] 1.01; 95% confidence interval [CI] 0.1.01-1.02), female sex (OR 1.38; 95% CI 1.29-1.47), black race (vs white, OR 1.44; 95% CI 1.32-1.57), Hispanic ethnicity (OR 1.23; 95% CI 1.08-1.40), QRS duration (OR 1.055 per 10 ms; 95% CI 1.038-1.072 per 10 ms), obstructive sleep apnea (OR 1.14; 95% CI 1.04-1.24), and implantation by a physician without specialized training (vs electrophysiology trained, OR 1.53; 95% CI 1.34-1.76).

CONCLUSION

LV lead implant failure is uncommon in the current era and is most commonly due to coronary sinus access failure. Predictors of LV lead implant failure included younger age, female sex, black race, Hispanic ethnicity, increased QRS duration, sleep apnea, and absence of electrophysiology training.

Short- and Long-Term Risk of Lead Dislodgement Events: Real-World Experience From Product Surveillance Registry

BACKGROUND

Lead dislodgement (LD) has been one of the most common early complications after cardiovascular implantable electronic device implant. However, limited data are available on the clinical characteristics and long-term outcomes of LD events. The aim of this study was to examine the risk factors, clinical significance, and management strategies of LD events after cardiovascular implantable electronic device implant.

METHODS

This study was a retrospective cohort analysis of 20 683 patients who underwent cardiovascular implantable electronic device implant between January 1, 2010 and January 31, 2020 in Medtronic's Product Surveillance Registry, with a mean follow-up time of 3.3±2.5 SD years. The study population was divided into 2 groups: group A with LD events (N=350) and group B without LD events (N=20 333).

RESULTS

During this period, 350 patients (1.69%) had LD events involving 371 leads (0.95%), among a total of 39 060 leads implanted. Passive fixation type (right atrium pacing lead, P=0.041), lower sensing amplitude (right ventricle defibrillating lead, P=0.020), and lower lead impedance at implant (right atrium pacing lead, P=0.009) were associated with increased LD risk. Multivariate analysis showed female sex (hazard ratio, 1.520, P=0.008) and higher body mass index (hazard ratio, 1.012, P=0.001) were independently associated with increased risk of LD events. LD events were not associated with significant changes in the long-term risks of cardiac and overall mortality. In group A, repositioning the dislodged leads increased the risk of a second LD event compared with implanting new leads (P=0.012).

CONCLUSIONS

Female sex and higher body mass index were associated with higher risk of LD events in the Product Surveillance Registry. Among patients with dislodged leads, implanting new leads was associated with lower risk of future LD events. Further studies on how to reduce LD risk and to improve management of these events are needed.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT01524276.

The usefulness of balloon occlusive left ventricular lead delivery in combination with the quadripolar active fixation lead for a patient with complex coronary venous morphology

Complex coronary vein morphology impedes the insertion of the left ventricular (LV) lead and reduces the effectiveness of cardiac resynchronization therapy (CRT). A 77-year-old woman underwent dual-chamber pacemaker implantation via the left subclavian approach for a complete atrioventricular block 17 years previously. She was hospitalized due to decompensated heart failure, and her cardiac rhythm completely depended on ventricular pacing at that time. Transthoracic echocardiography showed thinning of the ventricular septum in the basal region and pacing-induced dyssynchrony. She was clinically diagnosed with cardiac sarcoidosis with severe LV systolic dysfunction. She was referred for an upgrade to CRT. Given that prior contrast venography showed occlusion of the left subclavian vein, an additional LV lead was inserted through the right subclavian vein. Coronary venography showed a lateral vein that branched from the great cardiac vein with an acute angle and had multiple tortuosities in the peripheral branches. Since the LV lead placement was unsuccessful with the conventional method, we attempted the lead placement using the balloon occlusion technique (BOT). Lead delivery into the anatomical optimal lateral vein was successful by using BOT, and LV pacing from the most delayed basal region was achieved in combination with the active fixation LV lead.

<Learning objective: The balloon occlusion technique in cardiac resynchronization therapy implantation has been introduced to achieve left ventricular (LV) lead insertion into the coronary vein with a complex morphology. A quadripolar active fixation LV lead, which has been recently developed, has a low dislodgement rate and enables lead placement to the desired location. Application of conventional techniques in combination with the active fixation LV lead is expected to improve the success rate of optimal LV pacing in patients with complex coronary vein morphology.>

An active fixation quadripolar left ventricular lead for cardiac resynchronization therapy with reduced postoperative complication rates

BACKGROUND

The rate of left ventricular (LV) lead displacement after cardiac resynchronization therapy (CRT) remains high despite improvements in lead technology. In 2017, a novel quadripolar lead with active fixation technology became available in the UK.

METHODS

This was a retrospective, observational study analyzing device complications in 476 consecutive patients undergoing successful first-time implantation of a CRT device at a tertiary center from 2017 to 2020.

RESULTS

Both active (n = 135) and passive fixation (n = 341) quadripolar leads had similar success rates for implantation (99.3% vs. 98.8%, p = 1.00), although the pacing threshold (0.89 [0.60-1.25] vs. 1.00 [0.70-1.60] V, p = .01) and lead impedance (632 [552-794] vs. 730 [636-862] Ohms, p < .0001) were significantly lower for the active fixation lead. Patients receiving an active fixation lead had a reduced incidence of lead displacement at 6 months (0.74% vs. 4.69%, p = .036). There was no significant difference in the rate of right atrial (RA) and right ventricular (RV) lead displacement between the two groups (RA: 1.48% vs. 1.17%, p = .68; RV: 2.22% vs. 1.76%, p = .72). Reprogramming the LV lead after displacement was unsuccessful in most cases (successful reprogramming: Active fix = 0/1, Passive fix = 1/16) therefore nearly all patients required a repeat procedure. As a result, the rate of intervention within 6 months for lead displacement was significantly lower when patients were implanted with the active fixation lead (0.74% vs. 4.40%, p = .049).

CONCLUSION

The novel active fixation lead in our study has a lower incidence of lead displacement and re-intervention compared to conventional quadripolar leads for CRT.

Novel lead anchor technique using an active fixation quadripolar left ventricular lead in cardiac resynchronization therapy

In this report, we present a case of successful advancement of a LV lead into tortuous vessels. This was achieved by deep engagement of the coronary sinus with a cannulation catheter by applying the anchor technique using the Medtronic Attain Stability Quad lead.

Novel active fixation lead guided by electrical delay can improve response to cardiac resynchronization therapy in heart failure

AIMS

Cardiac resynchronization therapy (CRT) for heart failure (HF) recently has shown optimal results by targeting electrically delayed sites in coronary sinus (CS) branches. However this purpose often cannot be reached because of unstable left ventricular (LV) lead position. In current study were assessed the long-term effects of the novel active fixation LV lead in CS, guided by electrical delay (QLV), in patients with HF due to coronary artery disease.

METHODS

One hundred eighty-five consecutive patients underwent CRT with intraoperative evaluation of QLV in the target position of the LV lead. When the novel active fixation LV lead was available, 98 consecutive patients received it, composing the Fix group. They were compared with 87 patients with a conventional passive fixation lead (No Fix group). The final LV lead position was assessed by fluoroscopy. Clinical response to CRT was assessed within a period of about 3 years: patients experiencing HF rehospitalization and death due to HF were defined as non-responders.

RESULTS

There were no significant differences between groups in the final position of LV lead in left anterior oblique view (Pearson χ2  = 0.12; P = 0.73). In right anterior oblique view, a basal position was reached more in the Fix group (38%) than in the No Fix group (6.5%) (Pearson χ2  = 23.095; P < 0.001). QLV was significantly greater in the Fix group (122.6 ± 33.2 ms; SE = 3.6) than in the No Fix group (97.5 ± 37.8 ms; SE = 4.9) (t = 4.17; P < 0.001). Rehospitalizations for HF were 37 in the No Fix group and 14 in the Fix group. Deaths due to HF were 49 in the No Fix group and 18 in the Fix group. Survival analysis, assessed by Cox regression, showed that the Fix group had a better outcome both for HF rehospitalizations [hazard ratio (HR) = 0.48; 95% confidence interval (CI) = 0.25-0.9; P = 0.023] and death due to HF (HR = 0.55; 95% CI = 0.31-0.97; P = 0.04) in comparison with the No Fix group. Adjustment for baseline characteristics by multivariate analysis showed that an active fixation lead in CS, as a covariate, was still significant both for HF rehospitalizations (HR 0.46; 95% CI = 0.24-0.88; P = 0.019) and for death due to HF (HR 0.5; 95% CI = 0.28-0.9; P = 0.021).

CONCLUSIONS

The novel active fixation LV lead allowed to target sites with greater QLV. Often maximum QLV was documented in basal segments, were stability of conventional passive fixation leads is not enough. Patients receiving it experienced less HF rehospitalizations and less death due to HF. Active fixation lead in CS guided by QLV can improve long-term prognosis in patients with HF due to coronary artery disease undergoing to CRT.

Performance of an active fixation bipolar left ventricular lead vs passive fixation quadripolar leads in cardiac resynchronization therapy, a randomized trial

BACKGROUND

Usage of active fixation bipolar left ventricular (LV) leads represents an alternative approach to the more commonly used passive fixation quadripolar leads in cardiac resynchronization therapy (CRT). We compared a bipolar LV lead with a side screw for active fixation and passive fixation quadripolar LV leads.

METHODS

Sixty-two patients were before CRT implantations randomly allocated to receive a bipolar (n = 31) or quadripolar (n = 31) LV leads. Speckle-tracking radial strain echocardiography was used to define the LV segment with latest mechanical activation as the target LV segment. The electrophysiological measurements and the capability to obtain a proximal position in a coronary vein placed over the target segment were assessed.

RESULTS

Upon implantation, the quadripolar lead demonstrated a lower pacing capture threshold than the bipolar lead, but at follow-up, there was no difference. There were no differences in the LV lead implant times or radiation doses. The success rate in reaching the target location was not significantly different between the two LV leads.

CONCLUSIONS

The pacing capture thresholds were low, with no significant difference between active fixation bipolar leads and quadripolar leads. Active fixation leads did not promote a more proximal location of the stimulating electrode or a higher grade of concordance to the target segment than passive fixation leads.

Clinical outcome of cardiac resynchronization therapy in patients randomized to an active fixation bipolar left ventricular lead versus a passive quadripolar lead

Objectives: To compare the clinical outcome of cardiac resynchronization therapy (CRT) in patients receiving a bipolar left ventricular (LV) lead with a side helix for active fixation to the outcome in patients receiving a quadripolar passive fixation LV lead.Design: Sixty-two patients (mean age 72 ± 11 years) were blindly and randomly assigned to the active fixation bipolar lead group (n = 31) or to the quadripolar lead group (n= 31). The LV leads were targeted to the basal LV segment in a vein concordant to the LV segment with the latest mechanical contraction chosen on the basis of preoperative radial strain (RS) echocardiography.Results: At the 6-month follow-up (FU), the reduction in LV end-systolic volume and LV reverse remodelling responder rate, defined as LV end-systolic volume reduction >15%, was 77% in the active fixation group and 83% in the quadripolar group, which was not significantly different. At the 12-month FU, the LV ejection fraction (LVEF) did not differ between the groups. There were no significant differences between the two groups in changes in New York Heart Association (NYHA) functional class or Minnesota Living with Heart Failure Questionnaire score. The occurrence of phrenic nerve stimulation (PNS) was 19% in the active fixation group versus 10% in the quadripolar group (p=.30), and all cases were resolved by reprogramming the device. All patients were alive at the 12-month FU. There was no device infection.Conclusions: There were no significant differences between the active fixation group of patients and the quadripolar group of patients concerning improvement in echocardiographic parameters or clinical symptoms.ClinicalTrials.gov number, NCT04632472.

Caudocranial transseptal approach for placement of endocardial left ventricular leads

Cardiac resynchronization therapy (CRT) is associated with improvement in the quality of life, hospitalization rates, and mortality in patients with left ventricular dysfunction and evidence of the right ventricle-left ventricle (RV-LV) desynchrony. Implant failure rates and patient outcomes have improved with the advent of quadripolar leads, yet alternatives to traditional coronary sinus (CS) LV lead placement is sought for in a subset of advanced heart failure patients with difficult CS anatomy, phrenic nerve stimulation or in nonresponders. Endocardial left ventricular pacing (EnLVP) in chronically anticoagulated patients has been reported as an alternative using different approaches, techniques, and tools with acceptable short and long term adverse events. We present a case of successful EnLVP achieved for CRT using standard techniques and commonly available tools in a patient on chronic direct oral anticoagulation with recurrent heart failure admissions who failed traditional epicardial LV pacing.