Modified Pull-Through Technique for Cardiac Resynchronization Therapy Upgrades in Patients with Occluded Access Veins.

The number of procedures for upgrading implantable devices for cardiac resynchronization therapy has increased considerably during the last decade. A major challenge that operators face in these circumstances is occlusion of the access vein. We have modified a pull-through method to overcome this obstacle. Six consecutive patients with occluded access veins and well-developed collateral networks underwent a procedure in which the occluded vein was recanalized by snaring the existing atrial lead via transfemoral access. Upgrading the device was successful in all patients; none had intraprocedural complications. Our experience shows that our modified pull-through technique may be a feasible alternative for upgrading cardiac resynchronization therapy in patients with venous occlusion.

Epileptic seizure in a patient with an implantable cardioverter-defibrillator: Quo vadis right ventricular lead?

The case of a 77-year-old man admitted for suspected epileptic seizure is reported. Patient history showed implantation of a single-chamber implantable cardioverter-defibrillator (ICD) after cardiac arrest in 2007 with replacement in 2012 due to battery depletion; the patient reported no previous syncope, unconsciousness or seizures. Interrogation records of the ICD showed five ventricular tachyarrhythmia episodes that corresponded to the "seizure". Further examination revealed incorrect position of the RV-lead. Diagnosis was a provoked epileptic seizure due to undersensing of ventricular tachycardia because of improper ICD lead implantation in the coronary sinus. Treatment consisted of implantation of a new device with an additional ICD lead into the right ventricle.

A Novel Method of Axillary Venipuncture Using the Cephalic Vein as a Sole Anatomic Landmark.

The use of axillary venipuncture for pacemaker lead implantation has become a common technique. However, because of its relatively high complexity, it is still not the method of choice in most hospitals. As such, we propose an effective, simple, and safe technique for axillary venipuncture using only the cephalic vein as an anatomic landmark, with the possibility of selective cephalic contrast venography as a backup. A total of 108 patients were examined. After preparation of the cephalic vein, the puncture needle was inserted into the superficial pectoral muscle 1.5-2 cm medial to the cephalic vein and advanced in the direction parallel to the course of the cephalic vein. The needle was advanced up to 3-4 cm at an angle of 30° relative to the body surface, applying gentle suction during advancement. If after 3 attempts the axillary vein was not accessed, the same process was repeated 3-4 cm medial to the cephalic vein. If this was not effective, contrast venography of the axillary vein through the cephalic vein was performed. In 92.6% of all cases, the axillary vein was cannulated without fluoroscopic control, and in 7.4% of cases, fluoroscopic control and selective contrast venography were needed. A novel technique for axillary venipuncture using the cephalic vein as a single landmark is a simple, effective, and safe tool for pacemaker lead implantation. In some cases, selective cephalic contrast venography is an elegant and effective addition.

Improvement in acute contractility and hemodynamics with multipoint pacing via a left ventricular quadripolar pacing lead.

INTRODUCTION: A quadripolar left ventricular (LV) pacing can deliver multipoint pacing (MPP). It is unknown if this confers improved cardiac function compared to conventional cardiac resynchronization therapy (CRT). METHODS AND RESULTS: We aimed to characterize changes in acute cardiac contractility and hemodynamics with multisite left ventricular "multipoint" pacing (MPP) in a prospective multicenter study in patients implanted with a CRT-defibrillator incorporating a quadripolar LV lead. The device was programmed to deliver MPP acutely pacing with eight configurations of varying timing delays. Global peak LV radial strain and LV outflow velocity time integral (LVOT VTI) were measured for conventional CRT and each MPP configuration. Out of the eight tested MPP configurations, the one that yielded the best echocardiographic measurement for each patient was defined as "optimal MPP". Forty CRT recipients had complete radial strain datasets suitable for analysis. Compared to conventional CRT, the mean peak radial strain was significantly higher for the optimal MPP configuration (18.3 ± 7.4 vs. 9.3 ± 5.3%, p < 0.001), and at least one MPP configuration was significantly superior (>20%) in 63% of patients. LVOT VTI data were collected in a subset of 13 patients. In these patients, mean VTI was significantly higher for optimal MPP compared to conventional CRT (13.5 ± 2.7 vs. 10.9 ± 3.3 cm, p < 0.01). CONCLUSION: MPP delivered via a quadripolar LV lead resulted in a significant improvement in acute cardiac contractility and hemodynamics compared to conventional CRT in the majority of patients studied. CLINICAL TRIAL REGISTRATION: Clinicaltrials.gov identifier NCT01044784.

The ABC of a Simple Method for Pulmonary Vein Angiography.

Catheter-directed intervention to treat atrial fibrillation (AF) is becoming widely accepted procedure in current clinical practice. For assessment of pulmonary vein (PV) anatomy, angiography of left atrium (LA) and/or PV is often performed. We present a new, simple angiographic method for PVs and LA opacification using SL1 sheath. Total of 100 patients in our clinic underwent this procedure. In all of the cases good angiographic results were achieved. No immediate or late complications related to this procedure were observed.

Acute effects of multisite left ventricular pacing on mechanical dyssynchrony in patients receiving cardiac resynchronization therapy.

BACKGROUND: A novel quadripolar left ventricular (LV) pacing lead has the ability to deliver multisite LV pacing (MSLV). We set out to characterize the safety and changes in acute mechanical dyssynchrony with MSLV in cardiac resynchronization therapy (CRT) patients. METHODS AND RESULTS: Prospective multicenter study in 52 patients receiving CRT. An acute pacing protocol comprising 8 MSLV configurations covering a range of delays was compared with conventional CRT (baseline). Transthoracic tissue Doppler imaging (TDI) was used to measure the standard deviation of time to peak contraction of 12 LV segments (Ts-SD) and delayed longitudinal contraction. No ventricular arrhythmia occurred in any of the 52 patients. Complete TDI datasets were collected in 41 patients. Compared with baseline: 1) The mean Ts-SD was significantly lower for the optimal MSLV configuration (35.3 ± 36.4 vs 50.2 ± 29.1 ms; P < .001); 2) at least 1 MSLV configuration exhibited a significant dyssynchrony improvement in 63% of patients; and 3) the mean number of LV segments with delayed longitudinal contractions was significantly reduced with the optimal MSLV configuration (0.37 ± 7.99 vs 2.20 ± 0.19; P < .001). CONCLUSIONS: Acute MSLV was acutely safe, and a proportion of MSLV vectors resulted in a significant reduction in echocardiographic dyssynchrony compared with conventional CRT.

Occurrence of phrenic nerve stimulation in cardiac resynchronization therapy patients: the role of left ventricular lead type and placement site.

AIMS: Unwanted phrenic nerve stimulation (PNS) has been reported in ∼1 in 4 patients undergoing left ventricular (LV) pacing. The occurrence of PNS over mid-term follow-up and the significance of PNS are less certain. METHODS AND RESULTS: Data from 1307 patients enrolled in pre-market studies of LV leads manufactured by Medtronic (models 4193 and 4195 unipolar, 4194, 4196, 4296, and 4396 bipolar) were pooled. Left ventricular lead location was recorded at implant using a common classification scheme. Phrenic nerve stimulation symptoms were either spontaneously reported or identified at scheduled follow-up visits. A PNS-related complication was defined as PNS resulting in invasive intervention or the termination of LV pacing. Average follow-up was 14.9 months (range 0.0-46.6). Phrenic nerve stimulation symptoms occurred in 169 patients (12.9%). Phrenic nerve stimulation-related complications occurred in 21 of 1307 patients (1.6%); 16 of 738 (2.2%) in the unipolar lead studies, and 5 of 569 (0.9%) in the bipolar lead studies (P = 0.08). Phrenic nerve stimulation was more frequent at middle-lateral/posterior, and apical LV sites (139/1010) vs. basal-posterior/lateral/anterior, and middle-anterior sites (20/297; P= 0.01). As compared with an anterior LV lead position, a lateral LV pacing site was associated with over a four-fold higher risk of PNS (P= 0.005) and an apical LV pacing site was associated with over six-fold higher risk of PNS (P= 0.001). CONCLUSION: Phrenic nerve stimulation occurred in 13% of patients undergoing LV lead placement and was more common at mid-lateral/posterior, and LV apical sites. Most cases (123/139; 88%) of PNS were mitigated via electrical reprogramming, without the need for invasive intervention.

First prospective, multi-centre clinical experience with a novel left ventricular quadripolar lead.

AIMS: Cardiac resynchronization therapy (CRT) is sometimes complicated by elevated pacing thresholds and phrenic nerve stimulation (PNS), both of which may require that the coronary sinus lead be repositioned. The purpose of this study was to evaluate the performance of a novel quadripolar electrode lead and cardiac resynchronization therapy-defibrillator (CRT-D) device that enables electrical repositioning, potentially obviating a lead reposition procedure. METHODS AND RESULTS: Patients indicated for CRT were enrolled and received a quadripolar electrode lead and CRT-D device (Quartetmodel 1458Q and Promote Q; St Jude Medical, Sylmar, CA, USA). Electrical data, and the presence of PNS during pacing from each left ventricular (LV) configuration, were documented at pre-hospital discharge and at 1 month. Seventy-five patients were enrolled and 71 were successfully implanted with a Quartetlead. Electrical measurements were stable over the follow-up period. Ninety-seven per cent (64 of 66) of patients had one or more programmable configurations with a threshold < 2.5 V and no PNS vs. 86% (57 of 66) if only conventional bipolar configurations were considered. Physicians were able to use the increased programming options to manage threshold changes and PNS. CONCLUSION: The new quadripolar electrode LV lead provides more programming options to address common problems faced when managing CRT patients. Electrical measurements from new vectors are comparable with conventional configurations. Furthermore, 11% of patients in the study suffered PNS on all conventional bipolar vectors.

A randomized double-blind comparison of biventricular versus left ventricular stimulation for cardiac resynchronization therapy: the Biventricular versus Left Univentricular Pacing with ICD Back-up in Heart Failure Patients (B-LEFT HF) trial.

BACKGROUND: Biventricular (BiV) stimulation is the preferred means of delivering cardiac resynchronization therapy (CRT), although left ventricular (LV)-only stimulation might be as safe and effective. B-LEFT HF is a prospective, multicenter, randomized, double-blind study aimed to examine whether LV-only is noninferior to BiV pacing regarding clinical and echocardiographic responses. METHODS: B-LEFT HF randomly assigned 176 CRT-D recipients, in New York Heart Association class III or IV, with an LV ejection fraction < or =35% and QRS > or =130 milliseconds, to a BiV (n = 90) versus LV (n = 86) stimulation group. Clinical status and echocardiograms were analyzed at baseline and 6 months after CRT-D implant to test the noninferiority of LV-only compared with BiV stimulation. RESULTS: The proportion of responders was in line with current literature on CRT, with improvement in heart failure composite score in 76.2% and 74.7% of patients in BiV and LV groups, respectively. Comparing LV versus BiV pacing, the small differences in response rates and corresponding 95% CI indicated that LV pacing was noninferior to BiV pacing for a series of response criteria (combination of improvement in New York Heart Association and reverse remodeling, improvement in heart failure composite score, reduction in LV end-systolic volume of at least 10%), both at intention-to-treat and at per-protocol analysis. CONCLUSIONS: Left ventricular-only pacing is noninferior to BiV pacing in a 6-month follow-up with regard to clinical and echocardiographic responses. Left ventricular pacing may be considered as a clinical alternative option to BiV pacing.

Improved success rate of cardiac resynchronization therapy implant by employing an active fixation coronary sinus lead.

AIMS: Cardiac resynchronization therapy (CRT) is the standard treatment for heart failure with severe reduced left ventricular (LV) function and wide QRS complex. Coronary sinus (CS) lead implantation is challenging and accompanied by substantial dislocation rates. We evaluated the usage of an active fixation LV lead (Attain Starfix, Medtronic, MN, USA) with deployable lobes in challenging lead positions. METHODS AND RESULTS: Between September 2006 and August 2009, 678 CRT devices were implanted. In 82 patients (12%) (59 male, 70 +/- 10 years, 39 ICM, 41 DCM, 2 valvular CM, LVEF 28 +/- 9%, NYHA 3.0 +/- 0.4, QRS 169 +/- 29 ms), the Attain Starfix active fixation lead was used. The main reason was intra-operative dislodgement of one (n = 47) or two (n = 5) passive fixation leads during implantation or revision procedure (n = 30). Active fixation lead implantation was overall successful with 90% (n = 74). Anatomical peculiarity was mostly an optimal lead position in otherwise unstable proximal parts of the target vein or a circumscripted areal of optimal threshold without phrenic nerve stimulation. At median follow-up of 99 days the threshold remained stable (1.2 +/- 0.8 vs. 1.0 +/- 0.5 V at 0.5 ms). Revisions due to instability in ectatic vein (n = 1) after 12 months and extractions (n = 2) because of device perforation/infection after 6/15 months were performed without complication. CONCLUSION: The Attain Starfix active fixation lead proved to be an important option in anatomically challenging, otherwise unstable positions often located in the proximal part of the target vein. Lead revisions or extractions as late as 15 months after implantation were feasible.

Atrioventricular node ablation is not a prerequisite for cardiac resynchronization therapy in patients with chronic atrial fibrillation.

BACKGROUND: In drug-refractory heart failure, cardiac resynchronization therapy (CRT) is an established method in patients with sinus rhythm, severe reduced ejection fraction and broad QRS. Heart failure is known as a predisposition for atrial fibrillation (AF). However, the putative impact of atrioventricular node (AVN) ablation in chronic AF and CRT remains unclear. The aim of this study was to elucidate the effects of CRT in patients with chronic AF and the requirement for AVN ablation. METHODS: A total of 100 patients were included in the retrospective study, 64 with sinus rhythm (SR) and 36 with chronic AF with a mean duration of 2.8 +/- 0.5 years. Clinical parameters, QRS duration and echocardiographic parameters were compared at baseline and after a follow-up of 11 +/- 0.34 months in patients with SR and in 27 patients with chronic AF who received optimized medication to control ventricular rate and nine patients who underwent an AVN ablation. RESULTS: Baseline characteristics between patients with SR or AF in the presence or absence of AVN ablation were comparable. In each group, a significant improvement of NYHA class, ejection fraction could be observed, with an analogous reduction of QRS duration and a diminished left ventricular end-diastolic dimension after 11 +/- 0.34 months of CRT. CONCLUSIONS: The present results demonstrate a comparable improvement in left ventricular function and functional capacity in all treated groups. In conclusion, AVN ablation is not a prerequisite for CRT in patients with severe heart failure and chronic AF.

Different venous angioplasty manoeuvres for successful implantation of CRT devices.

AIMS: Cardiac resynchronization therapy (CRT) has growing impact in the treatment of severe heart failure Stenosis of coronary veins, complex structure of coronary sinus and occlusions of subclavian veins can limit lead passage in the target vein. METHODS AND RESULTS: Retrospective analysis of 705 implantation procedures of CRT devices from 1999 to July 2007 in a single centre to show the impact of venous angioplasty manoeuvres for successful placement of left ventricular lead. In 31 patients (3.5%) venous angioplasty was performed for LV-lead placement: 24 coronary veins (balloons 2.5-4.0 mm), 4 subclavian veins, 3 valves in the coronary sinus and one Marshall vein were dilated. Ring like strictures of coronary veins made high inflation pressures (16 +/- 4 atm) necessary. Success rate of LV lead placement were 99%. Complications were rare. CONCLUSIONS: Angioplasty of coronary or subclavian veins and valve structures of coronary sinus are a useful and safe tool for successful lead placement. The use of balloons of 3.0mm in size usually allows implantation of at least a unipolar lead.

A randomized comparison of triple-site versus dual-site ventricular stimulation in patients with congestive heart failure.

OBJECTIVES: We compared the effects of triple-site versus dual-site biventricular stimulation in candidates for cardiac resynchronization therapy. BACKGROUND: Conventional biventricular stimulation with a single right ventricular (RV) and a single left ventricular (LV) lead is associated with persistence of cardiac dyssynchrony in up to 30% of patients. METHODS: This multicenter, single-blind, crossover study enrolled 40 patients (mean age 70 +/- 9 years) with moderate-to-severe heart failure despite optimal drug treatment, a mean LV ejection fraction of 26 +/- 11%, and permanent atrial fibrillation requiring cardiac pacing for slow ventricular rate. A cardiac resynchronization therapy device connected to 1 RV and 2 LV leads, inserted in 2 separate coronary sinus tributaries, was successfully implanted in 34 patients. After 3 months of biventricular stimulation, the patients were randomly assigned to stimulation for 3 months with either 1 RV and 2 LV leads (3-V) or to conventional stimulation with 1 RV and 1 LV lead (2-V), then crossed over for 3 months to the alternate configuration. The primary study end point was quality of ventricular resynchronization (Z ratio). Secondary end points included reverse LV remodeling, quality of life, distance covered during 6-min hall walk, and procedure-related morbidity and mortality. Data from the 6- and 9-month visits were combined to compare end points associated with 2-V versus 3-V. RESULTS: Data eligible for protocol-defined analyses were available in 26 patients. No significant difference in Z ratio, quality of life, and 6-min hall walk was observed between 2-V and 3-V. However, a significantly higher LV ejection fraction (27 +/- 11% vs. 35 +/- 11%; p = 0.001) and smaller LV end-systolic volume (157 +/- 69 cm(3) vs. 134 +/- 75 cm(3); p = 0.02) and diameter (57 +/- 12 mm vs. 54 +/- 10 mm; p = 0.02) were observed with 3-V than with 2-V. There was a single minor procedure-related complication. CONCLUSIONS: Cardiac resynchronization therapy with 1 RV and 2 LV leads was safe and associated with significantly more LV reverse remodeling than conventional biventricular stimulation.

Mortality, morbidity, and complications in 3344 patients with implantable cardioverter defibrillators: results fron the German ICD Registry EURID.

ICDs are the therapy of choice in patients with life-threatening ventricular arrhythmias. Mortality, morbidity, and complication rates including appropriate and inappropriate therapies are unknown when ICDs are used in routine medical care and not in well-defined patients included in multicenter trials. Therefore, the data of 3,344 patients (61.1 +/- 12.1 years; 80.2% men; CAD 64.6%, dilated cardiomyopathy 18.9%; NYHA Class I-III: 19.1%, 54.3%, 20.1%, respectively; LVEF > 0.50: 0.234, LVEF 0.30-0.50: 0.472, LVEF < 0.30: 0.293, respectively) implanted in 62 German hospitals between January 1998 and October 2000 were prospectively collected and analyzed as a part of the European Registry of Implantable Defibrillators (EURID Germany). The 1-year survival rate was 93.5%. Patients in NYHA Class III and aLVEF < 0.30 had a lower survival rate than patients in NYHA Class I and a preserved LVEF (0.852 vs 0.975,P = 0.0001). Including the 1-year follow-up, 49.5% of patients had an intervention by the ICD, 39.8% had appropriate ICD therapies, 16.2% had inappropriate therapies. Overall, 1,691 hospital readmissions were recorded. The main causes for hospital readmissions were ventricular arrhythmias (61.3%) and congestive heart failure symptoms (12.9%). Thus, demographic data and mortality of patients treated with an ICD in conditions of standard medical care seems to be comparable and based on, or congruent with, the large secondary preventions trials. When ICDs are used in standard medical care, the 1-year survival rate is high, especially in patients with NYHA Class I and preserved LVEF. However, nearly half of all patients suffer from ICD intervention.