136-62: Clinical relevance with the Quartet® Left Ventricular quadripolar lead: QUARTO II Study

Abstract

Purpose: The QUARTO II study was an observational study that investigated the response to Cardiac Resynchronization Therapy (CRT) with the Quartetw Left Ventricular (LV) quadripolar lead. This sub-analysis evaluated the mortality and all-cause hospitalization (hosp) rate in patients programmed using the proximal pair of electrodes of this quadripolar lead (non-conventional vectors) versus the conventional bipolar vectors in real clinical practice. Methods: Patients !18 years underwent CRT Defibrillator device implantation with a Quartetw lead (St Jude Medical) and were programmed as per the investigators' criteria. Study data were collected at baseline and 6 months post-implant. CRT response was defined a priori as a reduction in Left Ventricular End Systolic Volume (LVESV) of .15% at 6 months post-implant. Summary of results: A total of 198 patients were enrolled in the study across 26 sites in Spain and Portugal. There were 5 (4.2%) deaths, 38 (31.7%) all-cause hosp and 41 (34.2%) patients with the combined endpoint (death and all-cause hosp) in patients with conventional programming; and 1 (1.3%), 8 (10.4%) and 9 (11.7%), respectively, in the non-conv group. Echocardiographic data at 6 months was collected in 87 (72.5%) patients with conv pacing vector and 59 (76.6 %) with non-conventional. Purpose: Recently, novel quadripolar coronary sinus leads (Acuity X4 family) have been introduced for cardiac resynchronization therapy (CRT). These leads potentially allow to overcome issues related to high thresholds and phrenic nerve stimulation. Three models (with different shapes and inter-electrode spacing) are currently available: the spiral long (Spiral L), spiral short (Spiral S) and Straight. The performance of these leads after implantation has not yet been reported. Our aim was to evaluate the electrical parameters and requirements for repositioning at 3 months follow-up. Methods: First consecutive 201 patients with a standard indication for CRT enrolled in the RALLY-X4 study following successful implantation of an Acuity X4 lead for standard CRT indications were followed-up prospectively. The protocol of this post-market follow up registry with . 800 enrolments specified an initial mandated analysis of a 200 patient dataset collected after at least 3 months post implant.Results: A total of 201 patients (169 males, mean age 67.1 + 9.6 years) were followed-up for a mean of 6.9+ 4.5months. No dislodgements were observed which required repositioning. Only 1/201 (0.5%) patient required reintervention due to phrenic nerve stimulation which could not be resolved by reprogramming. The electrical parameters (at the programmed configuration) are shown in the table below. Values are shown as mean + SD apart from the capture thresholds which are expressed as median (interquartile range):Threshold (V; n 5 198) 1.0 (0.7-1.5) 0.9 (0.7-1.2) 1.1 (0.7-1.5) Sensing (mV; n 5 186)17. Purpose of the study: Cardiac resynchronization therapy (CRT) is an established therapy to reduce morbidity and mortality in heart failure patients. ...

Response rate in cardiac resynchronization therapy patients implanted with a left ventricular quadripolar lead and the MultiPoint™ pacing feature early activated. QUARTO III

“…The observed percentage of super responders in this group is strikingly high in comparison to previous published data with conventional biventricular pacing. Interestingly, the QUARTO II study conducted by the same group using conventional biventricular pacing with quadripolar leads reported a super‐responder rate of 38% 12 …”

“…The Quarto II study was a prospectively study that evaluated the usefulness of the quadripolar lead Quartet, the patterns of programming and the response to CRT in 198 patients implanted with a CRT‐D device programmed into conventional single‐site biventricular pacing. The Quarto II showed a percentage of responders of 62% (reduction ≥15% in LVEV) at 6 months of follow‐up 12 …”

“…Main secondary endpoints were reverse LV remodelling measured by changes in LV end diastolic volume and diameter (LVEDV and LVEDD) and by changes in LVESV and left ventricle end systolic diameter (LVESD); changes in NYHA class and in clinical composite score at 6 months; clinical outcomes at 6 months (mortality and all‐cause hospitalization). Finally, a comparison with an historical control cohort corresponding to the patients involved in the previously conducted QUARTO II study 12 was prespecified. The Quarto II study was a prospectively study that evaluated the usefulness of the quadripolar lead Quartet, the patterns of programming and the response to CRT in 198 patients implanted with a CRT‐D device programmed into conventional single‐site biventricular pacing.…”

“…The primary endpoint of the study was to prospectively measure the CRT response rate at Finally, a comparison with an historical control cohort corresponding to the patients involved in the previously conducted QUARTO II study 12 was prespecified. The Quarto II study was a prospectively study that evaluated the usefulness of the quadripolar lead Quartet, the patterns of programming and the response to CRT in 198 patients implanted with a CRT-D device programmed into conventional single-site biventricular pacing.…”

“…The Quarto II showed a percentage of responders of 62% (reduction ≥15% in LVEV) at 6 months of follow-up. 12 All the echocardiography images were obtained by sites according to the study echo protocol at baseline and 6-month visit. They were submitted to the echo core lab for central evaluation and assessment.…”