The Zwolle experience with left bundle branch area pacing using stylet-driven active fixation leads.

AIMS: Left bundle branch area pacing (LBBAP) is a novel physiological pacing modality and is regarded as a viable alternative to His bundle pacing. LBBAP has mostly been performed with the lumen-less permanent pacing lead (SelectSecure™ Model 3830, Medtronic, Inc.) with a fixed helix. The aim of this study was to compare the non-stylet driven lumen-less lead (LLL) (Medtronic 3830) with a standard stylet-driven active fixation lead (SDL) (Tendril™ STS Model 2088TC-38, Abbott Laboratories) in terms of lead parameters, procedural success and complication rates. METHODS: Patients receiving a LBBA pacemaker in the Isala Hospital, The Netherlands, were prospectively enrolled. The majority received a standard right ventricular (RV) lead as backup, the implanter chose between LLL and SDL for the LBBAP lead. RESULTS: The study included 94 patients with a mean follow-up of 30 weeks. 30/31 LLL procedures were successful, compared with 62/63 in the SDL group. Including the participants that lost LBBAP during follow-up resulted in success rates of 90.3% for LLL versus 96.8% for SDL, P = 0.199. Mean number of deployments was significantly lower in the SDL group compared with the LLL group (2 ± 2.3 versus 4 ± 3.4, P = 0.005), implantation and procedural times were comparable. Pacing thresholds were low and remained low in both groups (at last follow-up 0.8 ± 0.30 V for LLL versus 0.6 ± 0.20 V for SDL). Complication rates did not differ significantly between both groups, P = 0.805. CONCLUSION: LBBAP using SDL is feasible and has comparable success rates with lower number of deployments of the active fixation screw.

Catheter ablation in highly symptomatic Brugada patients: a Dutch case series.

AIMS: In the past few years, promising results were described in targeting the arrhythmogenic substrate of the epicardial right ventricular outflow tract (RVOT) region in patients with Brugada syndrome (BrS). In this report, we describe our experience with endo- and epicardial substrate mapping and ablation in a series of highly symptomatic BrS patients. METHODS: This case series consists of seven patients with clinical BrS diagnosis who underwent catheter ablation in two Dutch hospitals (Isala hospital Zwolle; and Amsterdam University Medical Centre, location AMC, Amsterdam) and Hamad Heart Hospital in Qatar between 2013 and 2017. All patients had an ICD and recurrent ventricular arrhythmia (VA) episodes. All patients underwent endo-and epicardial mapping of the RVOT region. Elimination of all abnormal potentials and disappearance of BrS ECG pattern during the ablation procedure was the aimed endpoint. RESULTS: The study group consisted of seven patients with mean age 45.6 ± 16.9 years. Five patients had SCN5A mutations. One patient was excluded from analysis, since ablation could not be performed due to a very large low-voltage area and was later diagnosed with arrhythmogenic right ventricular cardiomyopathy, associated with an SCN5A mutation. One patient underwent both endo- and epicardial ablation to eliminate VA. During a mean follow-up of 3.6 ± 1.5 years, 5/6 patients remained VA free with two patients continuing quinidine. CONCLUSION: In patients with BrS and drug-refractory VA, ablation of the arrhythmogenic substrate in the RVOT region was associated with excellent long-term VA-free survival. The majority of these highly symptomatic BrS patients had an SCN5A mutation and also low-voltage areas epicardially.

Effective contact and outcome after pulmonary vein isolation in novel circular multi-electrode atrial fibrillation ablation.

INTRODUCTION: Pulmonary vein (PV) reconnection is frequently the cause of recurrence of atrial fibrillation (AF) after ablation. The second-generation gold multi-electrode ablation (Gold-MEA) catheter has a new design possibly resulting in improved lesion formation compared with its predecessor. We aimed to determine the association between effective radiofrequency applications with the Gold-MEA catheter and outcome after AF ablation. METHODS: 50 consecutive patients with paroxysmal AF underwent Gold-MEA (PVAC GOLDTM, Medtronic Inc.) ablation. The Gold-MEA catheter was navigated to the PV ostium by fluoroscopy. Duty-cycled radiofrequency ablations were performed at all PV ostia. Lesions were considered transmural when electrode temperature was >50 °C and power >3 W for >30 seconds. After the ablation procedure, patients visited the outpatient clinic at 3­month intervals including 24-hour Holter ECGs. RESULTS: Mean age was 56 years. All PVs were acutely isolated with the Gold-MEA catheter. Procedure time was 111 ± 22 minutes, ablation time was 24 ± 6.7 minutes and fluoroscopy time was 20 ± 8.1 minutes. No procedure-related complications were observed. One year after ablation, 60 % of patients were still free of arrhythmia recurrences after a single PV isolation attempt. The number of transmural lesions was associated with arrhythmia-free survival: 25.0 % in <72 transmural lesions, 64.3 % in 72-108 transmural lesions and 71.4 % in >108 transmural lesions (p = 0.029). CONCLUSION: PV isolation can be performed successfully with the Gold-MEA catheter, with a favourable safety profile. Transmurality of lesions was associated with ablation success and may improve AF ablation success.

Safety and long-term effects of renal denervation: Rationale and design of the Dutch registry.

BACKGROUND: Percutaneous renal denervation (RDN) has recently been introduced as a treatment for therapy-resistant hypertension. Also, it has been suggested that RDN may be beneficial for other conditions characterised by increased sympathetic nerve activity. There are still many uncertainties with regard to efficacy, safety, predictors for success and long-term effects. To answer these important questions, we initiated a Dutch RDN registry aiming to collect data from all RDN procedures performed in the Netherlands. METHODS: The Dutch RDN registry is an ongoing investigator-initiated, prospective, multicentre cohort study. Twenty-six Dutch hospitals agreed to participate in this registry. All patients who undergo RDN, regardless of the clinical indication or device that is used, will be included. Data are currently being collected on eligibility and screening, treatment and follow-up. RESULTS: Procedures have been performed since August 2010. At present, data from 306 patients have been entered into the database. The main indication for RDN was hypertension (n = 302, 99%). Patients had a mean office blood pressure of 177/100 (±29/16) mmHg with a median use of three (range 0-8) blood pressure lowering drugs. Mean 24-hour blood pressure before RDN was 157/93 (±18/13) mmHg. RDN was performed with different devices, with the Simplicity™ catheter currently used most frequently. CONCLUSION: Here we report on the rationale and design of the Dutch RDN registry. Enrolment in this investigator-initiated study is ongoing. We present baseline characteristics of the first 306 participants.

Characteristics of cardiac device infections in the Isala Hospital; a large volume tertiary care cardiology centre.

AIMS: To determine the frequency, characteristics and risk factors of cardiac device infections in the Isala Hospital. METHODS: We retrospectively studied all patients who underwent cardiac device procedures performed in the cardiac catheterisation lab and the operating room from 2010 to 2012. All patients who developed a cardiac device infection were reviewed for its characteristics. RESULTS: 31/2026 patients developed a cardiac device infection (1.5 %). One (3.2 %) patient died within 30 days of hospitalisation. Device infection rates for procedures in the catheterisation lab and operating room were similar (p = 0.60). Positive cultures were present in 27/31 (87 %) cases. These consisted predominantly of micro-organisms that are part of the skin flora (84 %). The mean time between device procedure and infection was 14 ± 21 months (range 0-79). Cardiac device infection was significantly associated with device revision, (65 % were revisions in patients with device infection vs. 30 % revisions in patients without device infection, p = 0.011) and placement of a left ventricular lead in pacemaker implantations (59 % of patients with vs. 51 % of patients without device infection, p < 0.001). CONCLUSION: The frequency of cardiac device infection was 1.5 % with a mortality of 3.2 % within 30 days, which is lower compared with other registries. Cardiac device infections were associated with device revisions and placement of left ventricular leads in pacemaker implantations.

Association of apical rocking with super-response to cardiac resynchronisation therapy.

BACKGROUND: Super-responders to cardiac resynchronisation therapy (CRT) show an exceptional improvement in left ventricular ejection fraction (LVEF). Previous studies showed that apical rocking was independently associated with echocardiographic response to CRT. However, little is known about the association between apical rocking and super-response to CRT. OBJECTIVES: To determine the independent association of LV apical rocking with super-response to CRT in a large cohort. METHODS: A cohort of 297 consecutive heart failure patients treated with primary indication for CRT-D were included in an observational registry. Apical rocking was defined as motion of the left ventricular (LV) apical myocardium perpendicular to the LV long axis. 'Super-response' was defined by the top quartile of LVEF response based on change from baseline to follow-up echocardiogram. Best-subset regression analysis identified predictors of LVEF super-response to CRT. RESULTS: Apical rocking was present in 45 % of patients. Super-responders had an absolute mean LVEF increase of 27 % (LVEF 22.0 % ± 5.7 at baseline and 49.0 % ± 7.5 at follow-up). Apical rocking was significantly more common in super-responders compared with non-super-responders (76 and 34 %, P < 0.001). In univariate analysis, female gender (OR 2.39, 95 % CI 1.38-4.11), lower LVEF at baseline (OR 0.91 95 % CI 0.87-0.95), non-ischaemic aetiology (OR 4.15, 95 % CI 2.33-7.39) and apical rocking (OR 6.19, 95 % CI 3.40-11.25) were associated with super-response. In multivariate analysis, apical rocking was still strongly associated with super-response (OR 5.82, 95 % CI 2.68-12.61). Super-responders showed an excellent clinical prognosis with a very low incidence of heart failure admission, cardiac mortality and appropriate ICD therapy. CONCLUSION: Apical rocking is independently associated with super-response to CRT.

Endoscopically visible steam pop during high-energy laser pulmonary vein ablation.

A 58-year-old woman with atrial fibrillation underwent laser balloon ablation at our centre. During 12 W ablation in the left superior pulmonary vein, a sudden steam pop was witnessed with displacement of the balloon catheter. Visualisation of the pulmonary vein antrum showed a red discolouration at the last ablation site.

Blood pressure response to renal nerve stimulation in patients undergoing renal denervation: a feasibility study.

During renal sympathetic denervation (RDN), no mapping of renal nerves is performed and there is no clear end point of RDN. We hypothesized high-frequency renal nerve stimulation (RNS) may increase blood pressure (BP), and this increase is significantly blunted after RDN. The aim of this study was to determine the feasibility of RNS in patients undergoing RDN. Eight patients with resistant hypertension undergoing RDN were included. A quadripolar catheter was positioned at four different sites in either renal artery. RNS was performed during 1 min with a pacing frequency of 20 Hz. After all patients successfully underwent RDN, RNS was repeated at the site of maximum BP response before RDN in either renal artery. Mean age was 66 years. During RNS, BP increased significantly from 108/55 to 132/68 mm Hg (P < 0.001). After RDN, systolic BP response at the site of maximum response to RNS was significantly blunted (+43.1 vs +9.3 mm Hg, P = 0.002). In three patients, a systolic BP increase >10 mm Hg was observed after RDN. In conclusion, RNS resulted in an acute temporary BP increase. This response was significantly blunted after RDN. RNS may potentially serve as an end point for RDN.

First Dutch experience with the endoscopic laser balloon ablation system for the treatment of atrial fibrillation.

INTRODUCTION: The endoscopic laser balloon ablation system (EAS) is a relatively novel technique to perform pulmonary vein isolation (PVI) in the treatment of atrial fibrillation (AF). The present study aimed to report the results of the first 50 patients treated in the Netherlands with the EAS in terms of procedural characteristics and AF-free survival. METHODS: Fifty patients successfully underwent EAS PVI. Median follow-up was 17 months. Mean age was 56 years, 82 % had paroxysmal AF. RESULTS: 99 % of the pulmonary veins were successfully isolated with the EAS. Mean procedure time was 171 min and mean fluoroscopy time was 36 min. One procedure was complicated by a temporary phrenic nerve palsy (2 %). During follow-up, 58 % of patients remained free of AF without the use of antiarrhythmic drugs. CONCLUSION: PVI with EAS is associated with a low risk of complications and a medium-term AF-free survival comparable with other PVI techniques.

Incidence of lead dislodgement, malfunction and perforation during the first year following device implantation.

BACKGROUND: The number of cardiac rhythm device implantations has been growing fast due to expanding indications and ageing of the population. Complications of implantation were rare in the trials. However, these involved small numbers and selected patients. Prospective real-life data are necessary to assess cardiac device implantation procedure-related risks. OBJECTIVE: To determine the incidence and predictors of lead-related re-intervention in a Dutch high-volume teaching hospital. METHODS: Data from all patients who underwent cardiac rhythm device implantation between January 2010 and December 2011 were collected in a prospective registry. At least 1 year of follow-up regarding re-intervention was available for all patients. Lead-related reasons for re-intervention were categorised into lead dislodgement, malfunctioning or perforation. RESULTS: One thousand nine hundred twenty-nine devices including 3909 leads were implanted. In 595 patients (30.8 %) a CRT-D/P was implanted. Lead-related re-intervention was necessary in 86 (4.4 %) patients; it was more common in younger and male patients, and due to either lead dislodgement (66 %), malfunctioning (20 %) or perforation (18 %). Coronary sinus lead dislodgement or malfunctioning was 1.4 %. Right atrial dislodgement (1.9 %, p < 0.001) or ICD lead dislodgement (1.8 %, p = 0.002) was more common than right ventricular dislodgement (0.3 %). The incidence of lead malfunctioning was higher (0.8 %) in ICD leads. An apical position of the right ventricular lead and lateral wall position of the right atrial lead were related to cardiac perforation. CONCLUSIONS: The incidence of lead-related re-intervention was comparable with the literature. The majority of re-interventions were due to lead dislodgements, particularly with right atrial and ICD leads. Re-intervention due to coronary sinus lead dislodgement was rare.

Characteristics of Sprint Fidelis lead failure.

Background. The Medtronic Sprint Fidelis ICD lead is prone to failure and the rate of failure seems to be increasing. The aim of this study was to investigate the rate of Sprint Fidelis lead failure, the characteristics, the mode of presentation and possible predictors of lead failure.Methods and Results. The rate, characteristics and presentation of Sprint Fidelis lead failure was assessed in this single-centre survey. 619 Sprint Fidelis ICD leads were implanted at our centre between December 2004 and August 2007. The mean follow-up was 32+/-10 (range 22-60) months; 35 patients (5.7%) required a lead re-implantation because of failure of the pace-sense conductor. Mean duration of lead survival was 23+/-12 (2-46) months and the rate of failure did not stabilise during follow-up. The mode of presentation was inappropriate shocks in 16 patients (45.7%), alarm alert in 12 patients (34.3%), and detection at routine follow-up in seven patients (20%). In 31 patients (89%), interrogation data revealed a sudden rise in impedance and/or frequent short VV intervals prior to lead failure and in five patients an isolated decrease of R wave (<2.5 mV). The interrogation data were not different from patients with shocks compared with patients without shocks. The interrogation data at routine follow-up in the first three months after implant were normal and stable.Conclusion. The rate of Sprint Fidelis lead failure reaches 5.7% at a mean follow-up duration of 32 months. The rate of failure does not seem to stabilise. Routine follow-up can not predict lead failure or prevent inappropriate shocks. (Neth Heart J 2010;18:12-7.).

Iron-induced platelet aggregation measurement: a novel method to measure platelet function in stenting for ST segment elevation myocardial infarction.

BACKGROUND: Iron and (stainless) steel are potent platelet aggregation activators, and may be involved in stent thrombosis, a serious complication after intracoronary stenting. Current platelet function tests are suboptimal, because of inappropriate agonists and/or lack of reproducibility. We tested the feasibility and reproducibility of a novel platelet function test using stainless steel as an agonist and compared it with other platelet function tests. MATERIALS AND METHODS: In 111 patients with acute ST segment elevation myocardial infarction (STEMI), duplo measurements of iron (Fe)-induced platelet aggregation (FIPA) were performed after clopidogrel, acetylsalicylic acid and/or tirofiban treatment. Within 1 h, citrated blood samples drawn from the femoral sheath before primary percutaneous coronary intervention were added to 100 mg of low carbon steel and after 5 s mixing with vortex, the samples were incubated for 15 min. The ratio between the non-aggregated platelets in the agonist sample and platelets in a reference sample was calculated as the platelet aggregation inhibition. RESULTS: FIPA measurement was highly reproducible (correlation coefficient (R)=0.942, P<0.001 between duplo samples). FIPA correlated well with adenosine diphosphate-induced platelet aggregation (R=0.83, P<0.001) but weakly with platelet function analyser-100 bleeding time (R=0.56, P<0.001). FIPA could be measured in patients in which platelet aggregation could not be measured by platelet function analyser-100 or after adenosine diphosphate. CONCLUSION: This study showed good reproducibility of a novel platelet function test using stainless steel as an agonist and showed correlation with validated platelet function tests. We found that the novel platelet function test is a suitable test for measurement of platelet aggregation inhibition in patients undergoing stenting for STEMI, even when they are taking multiple antiplatelet regimens.

Impaired platelet inhibitory effect of a single dose of acetylsalicylic acid in patients with unstable coronary artery syndrome in comparison with healthy volunteers.

BACKGROUND AND AIM: Controversial reports have been published about the efficiency of potent platelet inhibitors in patients with coronary artery syndrome (CAS). We therefore questioned whether a functional change in platelets affects the patient's response to ASA. STUDY DESIGN AND METHODS: Nineteen consecutive patients presenting with unstable coronary syndrome and 15 healthy volunteers were included. No platelet inhibitory drugs or coumarin were used in either group before the study. Platelet aggregation tests were performed on baseline samples and after a single dose of ASA. Afterwards, all patients underwent coronary angiography to exclude non-CAS. RESULTS: In the patient group (n=15 after exclusion) no significant increase in bleeding constant was found after ASA, using a PFA analyser, in contrast to the control group. The maximal velocity and the maximal percentage optical platelet aggregation using ADP was significantly more reduced in the control group. ASA did not significantly reduce the thromboxane B2 production in the patient group. CONCLUSION: ASA has less platelet inhibitory effects in patients with unstable CAS in comparison with healthy volunteers. Platelets, in the hyperactive state of unstable CAS, prove to be less subject to inhibition. This might add to the explanation of the lack of efficiency of platelet inhibitory drugs to prevent thrombotic complications after PTCA and platelet aggregation onto stent surfaces in patients with acute CAS.