Relationship of NT-ProBNP and pacemaker parameters in patients with sick sinus syndrome?

Objectives: NT-ProBNP could influence the pacemaker parameters in patients with sick sisnus syndrome? Methods and Results: 93 patients with sick sinus syndrome were implanted 2 chambers pacemaker with mean aged 61,19±14,95 years old and 37,6% of male. The pacemaker parameters of ventricular lead include: Pacing thresholds were measured 0.75 ± 0.17 V, sensing amplitudes were measured 9,93 ± 4.01 mV, and lead impedances were measured 710,06 ± 130,86 ᾨ. The pacemaker parameters of atrial lead include: Pacing thresholds were measured 1,06 ± 0,29 V, sensing amplitudes were measured 2,58 ± 1,23 mV, and lead impedances were measured 509,13 ± 69,22 ᾨ. There is not significantly relationships of NT-ProBNP and pacemaker parameters of ventricular lead, atrial lead impedance, atrial lead sensing amplitudes (p>0,05). However, there is significantly relationship of NT-ProBNP and atrial lead pacing threshold (r=0,34; p=0,003). Conclusion: There is significantly relationship of NT proBNP and atrial lead pacing threshold in patients with sick sinus syndrome who were implanted the pacemaker.

Left Ventricular Lead Placement Guided by Reduction in QRS Area

Background: Reduction in QRS area after cardiac resynchronization therapy (CRT) is associated with improved long-term clinical outcome. The aim of this study was to investigate whether the reduction in QRS area is associated with hemodynamic improvement by pacing different LV sites and can be used to guide LV lead placement. Methods: Patients with a class Ia/IIa CRT indication were prospectively included from three hospitals. Acute hemodynamic response was assessed as the relative change in maximum rate of rise of left ventricular (LV) pressure (%∆LVdP/dtmax). Change in QRS area (∆QRS area), in QRS duration (∆QRS duration), and %∆LVdP/dtmax were studied in relation to different LV pacing locations within a patient. Results: Data from 52 patients paced at 188 different LV pacing sites were investigated. Lateral LV pacing resulted in a larger %∆LVdP/dtmax than anterior or posterior pacing (p = 0.0007). A similar trend was found for ∆QRS area (p = 0.001) but not for ∆QRS duration (p = 0.23). Pacing from the proximal electrode pair resulted in a larger %∆LVdP/dtmax (p = 0.004), and ∆QRS area (p = 0.003) but not ∆QRS duration (p = 0.77). Within patients, correlation between ∆QRS area and %∆LVdP/dtmax was 0.76 (median, IQR 0.35; 0,89). Conclusion: Within patients, ∆QRS area is associated with %∆LVdP/dtmax at different LV pacing locations. Therefore, QRS area, which is an easily, noninvasively obtainable and objective parameter, may be useful to guide LV lead placement in CRT.

Anodal Capture for Multisite Pacing with a Quadripolar Left Ventricular Lead: A Feasibility Study

Background: Up to 40% of patients are CRT non-responders. Multisite pacing, using a unique quadripolar lead, also called multipoint/multipole pacing (MPP), is a potential alternative. We sought to determine the feasibility of intentional anodal capture using a single LV quadripolar lead, to reproduce MPP without the need of a specific algorithm (so-called “pseudo MPP”). Methods: Consecutive patients implanted with a commercially available CRT device and a quadripolar LV lead in our department were prospectively included. The electric charge (Q, in Coulomb) of RV and LV pacing spikes were calculated for all available LV pacing configurations at the threshold. The best MPP was defined as the configuration with the lowest consumption (QRV + Qbest LV1 + Qbest LV2). The best “pseudo MPP” (QRV + QLV1–LV2 with anodal capture) and best BVp (QRV + Qbest LV) were also calculated. A theoretical longevity was estimated for each configuration at the threshold without a safety margin. Results: A total of 235 configurations were tested in 15 consecutive patients. “Pseudo-MPP” was feasible in 80% of patients with 3.1 ± 2.6 vectors available per-patient and LVproximal-LVdistal (most distant electrodes) vectors were available in 47% of patients. Each MPP pacing spike electrical charge was comparable to “pseudo-MPP” (18,428 ± 6863 µC and 20,528 ± 5509 µC, respectively, p = 0.15). Theoretical longevity was 6.2 years for MPP, 5.6 years for “pseudo-MPP” and 13.7 years for BVp. Conclusions: “Pseudo MPP” using intentional anodal capture with a quadripolar left ventricular lead, mimicking conventional multisite pacing, is feasible in most of CRT patients, with comparable energy consumption. Further studies on their potential clinical impact are needed.

Perioperative Sensor and Algorithm Programming in Patients with Implanted ICDs and Pacemakers for Cardiac Resynchronization Therapy

Background: ICDs and pacemakers for cardiac resynchronization therapy (CRT) are complex devices with different sensors and automatic algorithms implanted in patients with advanced cardiac diseases. Data on the perioperative management and outcome of CRT carriers undergoing surgery unrelated to the device are scarce. Methods: Data from 198 CRT device carriers (100 with active rate responsive sensor) were evaluated regarding perioperative adverse (device-related) events (A(D)E) and lead parameter changes. Results: Thirty-nine adverse observations were documented in 180 patients during preoperative interrogation, which were most often related to the left-ventricular lead and requiring intervention/reprogramming in 22 cases (12%). Anesthesia-related events occurred in 69 patients. There was no ADE for non-cardiac surgery and in pacemaker-dependent patients not programmed to an asynchronous pacing mode. Post-operative device interrogation showed significant lead parameter changes in 64/179 patients (36%) requiring reprogramming in 29 cases (16%). Conclusion: The left-ventricular pacing lead represents the most vulnerable system component. Comprehensive pre and post-interventional device interrogation is mandatory to ensure proper system function. The type of ICD function suspension has no impact on each patient’s outcome. Precautionary activity sensor deactivation is not required for non-cardiac interventions. Routine prophylactic device reprogramming to asynchronous pacing appears inessential. Most of the CRT pacemakers do not require surgery-related reprogramming.

616 Endocardial lead placement guided by high resolution voltage mapping in a patient with recurrent failure of transvenous pacing system

Methods and results A 58 years-old man was admitted to our intensive care unit for syncope due to inconstant capture of epicardial ventricular lead. His cardiovascular history began 20 years before when he underwent single chamber pacemaker implantation with insertion of a passive fixation ventricular lead for symptomatic complete atrio ventricular block (AVB). Electrical parameters were good at implantation. However, during follow-up a gradual and progressive increase of pacing threshold occurred, with no changes in impedance values, finally leading to complete loss of ventricular capture. Hence, 2 years later, the lead was extracted and a new transvenous ventricular lead was placed in septal position. All electrical parameters were optimal at the end of the procedure. However, in the following months threshold values gradually increased as previously observed. The referring clinicians decided to surgically extract both the device and transvenous lead and to implant an epicardial ventricular lead connected to an abdominal generator. The pacemaker worked properly for about 17 years until he was transferred to our institution with evidence of inconstant lead capture at maximum pacing outputs. A temporary transvenous pacemaker was immediately inserted. Clinical examination, laboratory exams, and echocardiography were normal. Cardiac magnetic resonance (MRI) was not feasible due to the epicardial lead. Thus, in order to obtain cardiac substrate characterization, we decided to perform high density multielectrode voltage mapping of the right ventricular endocardium with HD Grid multielectrode mapping catheter (HD Grid mapping catheter sensor enabled, Abbott Technologies, Minneapolis, MN). Electroanatomic voltage map allows distinction of areas of healthy myocardium (>1.5 mV) from scar tissue (<0.5 mV). Unexpectedly, voltage mapping highlighted no scar zones, showing a globally normal endomyocardial surface. Therefore, a new endocavitary pacemaker was inserted in right prepectoral region and an active fixation right ventricular lead was placed on mid-ventricular septum. A backup pacing lead was placed in a more apical position in an area of endocardial healthy myocardium. Post-procedural sensing, impedance and capture threshold were optimal (0.3 V × 0.4 ms for mid-septal lead and 0.3 × 0.4 ms for the other one). At 1 month follow-up mid-septal lead’s threshold was slightly increased (1.0 V × 0.4 ms) and further increase was observed at 3-month outpatient visit (1.75 V × 0.4 ms). Capture threshold of the other lead and other parameters were stable. The patient received remote monitoring for home surveillance of the implanted system. Home monitoring shows a trend toward a progressive increase of pacing threshold of the mid-septal lead and stable value of the other electrode. Conclusions The present report suggests an innovative use of high-density mapping with HD Grid catheter to characterize endocardial right ventricular myocardium in a patient with contraindication to cardiac MRI and recurrent failure of previous implanted pacing systems for unknown reason and to guide effective lead placement in areas of normal endocardial voltage. Combined use of telemedicine and high-resolution mapping technique allowed us to avoid unnecessary high risk reintervention for novel epicardial lead placement.

656 Cough, a rare and not well recognized symptom of lead perforation

Aims Along with relevant progress in technology, pacemaker implantation is continuously improving its safety and efficacy in treating patients with bradyarrhythmias. Despite this, this procedure has several complications, including haematoma, pneumothorax, lead dislodgement, infection, lead perforation, and tamponade. Methods and results A 64-year-old woman underwent loop recorder implantation, after recurrent loss of consciousness, in order to assess arrhythmic causes of syncope. Two weeks later, an episode of paroxysmal complete AV block, conditioning a pause of 3 s, was recorded. Thus, the patient was scheduled for urgent dual-chamber pacemaker implantation. No complication apparently occurred during the procedure. An active fixation ventricular lead was positioned in right ventricular septal apex while passive fixation atrium lead in the right appendage. Soon after implantation the patient started to suffer by non-productive cough, clearly related to ventricular stimulation, either in DDD or in VVI pacing modality. During spontaneous ventricular activation (RBBB) no symptoms occurred. Transthoracic echocardiography, performed the day after implantation, revealed a small pericardial effusion (diastolic diameter < 10 mm) along the apical segments, near the tip of the right ventricular lead. Suspicion of right ventricular lead perforation arised. The patient underwent urgent contrast chest CT confirming pericardial effusion, and showing an intramyocardium placement of the right ventricular apical lead. No active bleeding in pericardium was observed. Due to persistence of symptoms, we decided to perform right ventricular lead repositioning in right middle septum, with pericardiocentesis back-up promptly available. Post-procedure, palpitation, and cough abruptly disappeared. After 3 months follow-up, no significant symptoms were reported and pericardial effusion gradually disappeared. Conclusions We describe a singular case of cough, as atypical symptom immediately after pacemaker implantation. Pericardial effusion and contrast-CT showing intra-myocardial position of the tip guided our suspicion to a possible right ventricular lead microperforation. Although right ventricular lead parameters were completely normal this findings didn’t exclude RV perforation. The lead perforation is known as a rare complication of device implantation. Typical symptoms of RV lead perforation are chest pain and hypotension. The patient described in our case showed a haemodynamically stable pericardial effusion accompanied by non-productive cough, clearly time-related to RV stimulation. In literature, there is only another similar case report. The cough is a rare and not well recognized symptom of lead perforation. Early diagnosis of RV perforation allows to perform urgently and safely (pericardiocentesis back-up) lead replacement/repositioning. Echocardiography and contrast-CT could be useful in order to assess a possible pericardial effusion or intramyocardial/pericardial position of RV lead tip.

Predictors of worsening TR severity after right ventricular lead placement: any added value by post-procedural fluoroscopy versus three –dimensional echocardiography?

Background The effect of right ventricular (RV) leads on tricuspid valve has been already raised concerns, especially in terms of prognostic implication. For such assessment, three-dimensional transthoracic echocardiography (3D-TTE) has been used previously but there was no data on the use of post-procedural fluoroscopy in the literature. Methods We prospectively enrolled 59 patients who underwent clinically indicated placement of pacemaker or implantable cardioverter defibrillator (ICD). Vena contracta (VC) and tricuspid regurgitation (TR) severity were measured using two-dimensional transthoracic echocardiography (2D-TTE) at baseline. Follow up 3D-TTE was performed 6 months after device implantation to assess TR severity and RV lead location. Results Lead placement position in TV was defined in 51 cases.TR VC was increased after the lead placement, compared to the baseline study (VC: 3.86 ± 2.32 vs 3.18 ± 2.39; p = 0.005), with one grade worsening in TR in 25.4% of cases. The mean changes in VC levels were 1.14 ± 0.67 mm. Among all investigated parameters, VC changes were predicted based on lead placement position only in 3D-TTE (p < 0.001) while the other variables including fluoroscopy parameters were not informative. Conclusion The RV Lead location examined by 3D-TTE seems to be a valuable parameter to predict the changes in the severity of the tricuspid regurgitation. Fluoroscopy findings did not improve the predictive performance, at least in short term follow up.

Surgical epicardial left ventricular lead implantation as a troubleshooting step for a left ventricular lead fracture following difficult transvenous implants in cardiac resynchronisation therapy patients: a case report

Troubleshooting of left ventricular (LV) lead fractures in cardiac resynchronisation therapy patients is important, especially for those with limited and problematic transvenous LV lead placement. In this case, surgical epicardial LV lead implantation was employed.