Interventional device implantation, Part I: Basic techniques to avoid complications: A hands-on approach.

INTRODUCTION: The essence of cardiac resynchronization therapy (CRT) is biventricular (BiV) pacing, which involves implanting pacing leads in both the right ventricle (RV) and left ventricle (LV). Unlike traditional RV pacing, many hurdles lie ahead of successful LV lead implantation. METHODS AND RESULTS: In this review, we first highlight the importance of optimizing the patient and the tools. Next, we describe the CRT tools developed over several decades, to facilitate successful implantation. Thereafter, we provide a streamlined step-by-step summary of the basic BiV implantation procedure. Lastly, we discuss some commonly encountered challenges during implantation and the techniques to tackle them. CONCLUSION: A systematic approach to every step of the implantation process can reduce procedure time, decrease patient exposure to radiation and contrast, and minimize complications. The use of right tools and techniques can enable all implanters to become more successful with BiV implantation.

"Retained wire femoral lead removal and fibroplasty" for obtaining venous access in patients with refractory venous obstruction.

BACKGROUND: Patients with wire and catheter refractory venous occlusion are traditionally referred for pectoral transvenous lead extraction (TLE) to obtain venous access. TLE causes 1-2 mm circumferential mechanical or laser destruction of tissue surrounding the lead(s). This not only exposes the patient to the risk of major complications but also can damage nontargeted leads. We present a series of patients where retained wire femoral lead removal and fibroplasty was used to obtain venous access in patients with refractory obstruction. METHODS: Between 2008 and 2021, we identified 17 patients where retained wire lead removal followed by fibroplasty was used to retain venous access. Demographic and procedural data were obtained by retrospective review of patient charts. RESULTS: We were able to successfully obtain venous access in all 17 patients in whom this technique was attempted. In two patients the target lead was less than or equal to 1 year old. In the remaining 15 patients, the average dwell time of the target lead(s) was 6 years. There were no procedure-related complications, and no changes in the parameters of other leads were noted. CONCLUSION: Retained wire femoral lead removal and fibroplasty is safe and highly efficacious at obtaining venous access in patients with refractory venous occlusion. If the target lead(s) is less than or equal to 1 year old, this technique can help obtain venous access at the time of the initial surgery, hence avoiding the need for TLE. Furthermore, in patients referred for TLE to obtain venous access, this technique by avoiding the use of TLE tools spares the patient of the associated risks.

Rationale and design of a randomized trial to assess the safety and efficacy of MultiPoint Pacing (MPP) in cardiac resynchronization therapy: The MPP Trial.

BACKGROUND: Although the majority of Class III congestive heart failure (HF) patients treated with cardiac resynchronization therapy (CRT) show a clinical benefit, up to 40% of patients do not respond to CRT. This paper reports the design of the MultiPoint Pacing (MPP) trial, a prospective, randomized, double-blind, controlled study to evaluate the safety and efficacy of CRT using MPP compared to standard biventricular (Bi-V) pacing. METHODS: A maximum of 506 patients with a standard CRT-D indication will be enrolled at up to 50 US centers. All patients will be implanted with a CRT-D system (Quartet LV lead Model 1458Q with a Quadra CRT-D, Abbott) that can deliver both MPP and Bi-V pacing. Standard Bi-V pacing will be activated at implant. At 3 months postimplant, patients in whom the echocardiographic parameters during MPP are equal or better than during Bi-V pacing are randomized (1:1) to either an MPP or Bi-V arm. RESULTS: The primary safety endpoint is freedom from system-related complications at 9 months. Each patient's response to CRT will be evaluated using a heart-failure clinical composite score, consisting of a change in NYHA functional class, patient global assessment score, HF events, and cardiovascular death. The primary efficacy endpoint is the proportion of responders in the MPP arm compared with the Bi-V arm between 3 and 9 months. CONCLUSION: This trial seeks to evaluate whether MPP via a single quadripolar LV lead improves hemodynamic and clinical responses to CRT, both in clinical responders and nonresponders.

Biventricular pacing for atrioventricular block and systolic dysfunction.

BACKGROUND: Right ventricular pacing restores an adequate heart rate in patients with atrioventricular block, but high percentages of right ventricular apical pacing may promote left ventricular systolic dysfunction. We evaluated whether biventricular pacing might reduce mortality, morbidity, and adverse left ventricular remodeling in such patients. METHODS: We enrolled patients who had indications for pacing with atrioventricular block; New York Heart Association (NYHA) class I, II, or III heart failure; and a left ventricular ejection fraction of 50% or less. Patients received a cardiac-resynchronization pacemaker or implantable cardioverter-defibrillator (ICD) (the latter if the patient had an indication for defibrillation therapy) and were randomly assigned to standard right ventricular pacing or biventricular pacing. The primary outcome was the time to death from any cause, an urgent care visit for heart failure that required intravenous therapy, or a 15% or more increase in the left ventricular end-systolic volume index. RESULTS: Of 918 patients enrolled, 691 underwent randomization and were followed for an average of 37 months. The primary outcome occurred in 190 of 342 patients (55.6%) in the right-ventricular-pacing group, as compared with 160 of 349 (45.8%) in the biventricular-pacing group. Patients randomly assigned to biventricular pacing had a significantly lower incidence of the primary outcome over time than did those assigned to right ventricular pacing (hazard ratio, 0.74; 95% credible interval, 0.60 to 0.90); results were similar in the pacemaker and ICD groups. Left ventricular lead-related complications occurred in 6.4% of patients. CONCLUSIONS: Biventricular pacing was superior to conventional right ventricular pacing in patients with atrioventricular block and left ventricular systolic dysfunction with NYHA class I, II, or III heart failure. (Funded by Medtronic; BLOCK HF ClinicalTrials.gov number, NCT00267098.).

Impact of using a telescoping-support catheter system for left ventricular lead placement on implant success and procedure time of cardiac resynchronization therapy.

BACKGROUND: Proper positioning of the left ventricular (LV) lead improves clinical outcomes and survival in patients receiving cardiac resynchronization therapy (CRT). Techniques of LV lead insertion using contrast injection and a telescoping system of delivery catheters to support advancement of the lead into the target branch may allow more efficient, targeted lead placement. We sought to evaluate the impact of an LV lead implant approach using telescoping-support catheters (group TS) on success rate, lead location, and procedural time compared to standard over-the-wire implant techniques (group OTW). METHODS: Four hundred thirty-seven consecutive patients undergoing CRT implantation were divided into group TS (n = 105) or group OTW (n = 332) based upon a review of the operative technique used for LV lead implantation. The primary outcome was success of LV lead implantation at the index procedure. Secondary endpoints included optimal positioning of the LV lead and reduction in procedural fluoroscopy time. RESULTS: Failed LV lead placement was lower (1.9% vs 8.1%, P = 0.02) and optimal lead positioning was achieved more often for group TS than group OTW (87% vs 75%, P = 0.01). In addition, there were significantly shorter fluoroscopy times for group TS versus group OTW (29.6 minutes vs 41.9 minutes, P < 0.01). CONCLUSION: A CRT-implant approach using contrast injection and a telescoping-support catheter system results in fewer failed LV lead implants, improved LV lead location, and shorter procedure times.

Prolapsed double-canted bipolar left ventricular lead for pacing the left atrium via the coronary sinus: experience in 11 patients.

AIMS: High thresholds and frequent lead dislodgement limit pacing the left atrium (LA) from the mid to distal coronary sinus (CS). The aim of this report is to describe a method for and the results of prolapsing a double-canted bipolar lead into the mid-to-distal CS to eliminate lead dislodgement and improve pacing thresholds. METHODS AND RESULTS: After CS access the 9 Fr. anatomic sheath is withdrawn to the right atrium (RA) over an extra support wire. A double-canted bipolar lead is advanced into the RA until the proximal bend is outside the tip of the sheath. With the stylet withdrawn to the proximal bend, the sheath and lead are advanced over the wire back into the CS. The lead distal to the proximal bend is prolapsed beside the sheath as the tip of the sheath enters the CS. The lead was successfully prolapsed in 11 consecutive patients. In one patient, capture was >5 V in all locations. Of the 10 successful implants, the acute thresholds were: mean 1.53 V, median 1.35 V, range 0.4-4.0 V. Chronic thresholds were: mean 2 V, median 2 V range 0.4-4.0 V. There were no displaced leads or lead fractures through 6-10 months of follow-up. CONCLUSIONS: Prolapse of a commercially available double-canted bipolar passive fixation lead eliminates lead dislodgment and improves thresholds providing a means for permanent pacing of the LA from the mid to distal CS and provides the design principles for a dedicated lead.

Azygous Vein Coil Implantation in Left Ventricular Assist Device Patients: A Hands-on Approach.

Recently, there have been reports of left ventricular assist device (LVAD) patients presenting with multiple ineffective implantable cardioverter-defibrillator (ICD) shocks. In such patients, the placement of an azygous vein coil by providing an alternative anteroposterior trajectory of the electrical shock vector can enable successful defibrillation. This review discusses a hands-on approach to azygous vein coil implantation. Additionally, we compare our tools and technique to those that have been previously described by other operators. From 2018 to 2021, eight patients were identified who underwent azygous vein coil implantation at MedStar Washington Hospital Center using a specific technique and tools. Demographic and procedural data were obtained by a retrospective review of patient charts, procedure logs, fluoroscopy, and venography performed during coil implantation. The indication for azygous vein coil implantation was ineffective ICD shocks in seven patients. The presenting rhythm was ventricular fibrillation in six (75%) cases and sustained ventricular tachycardia in two (25%) cases. Using the approach described, we were able to successfully implant an azygous vein coil in all eight (100%) patients. There were no procedure-related complications. Postimplantation, defibrillation threshold (DFT) testing was successfully performed in six of eight (75%) patients. One patient failed DFT testing despite placement of an azygous vein coil. In another patient, DFT testing was not performed because the patient was in atrial fibrillation and was not systemically anticoagulated. In conclusion, the placement of an azygous vein coil in LVAD patients with failed ICD shocks using the tools and technique described in this report is safe and highly efficacious (successful in 100% of cases).

Successful implantation of a left ventricular lead in an anomalous coronary sinus.

We describe the case of a 56-year-old man who was referred for CRT implantation and found to have anomalous CS. Catheterization of the CS initially failed due to this anomaly. However, a single large posterior-lateral branch with diminutive CS in the atrioventricular groove allowed for successful implantation of the LV lead.

Ventricular Fibrillation Cardiopulmonary Arrest Following Micra™ Leadless Pacemaker Implantation.

Leadless cardiac pacemakers such as the Micra™ transcatheter leadless pacing system (Medtronic, Minneapolis, MN, USA) are an alternative to traditional transvenous pacemakers. Implantation of leadless pacemakers, albeit safe, may be associated with complications, including cardiac tamponade; high capture thresholds; and, rarely, ventricular arrhythmias. We report a case of ventricular fibrillation arrest following the implantation of a Micra™ leadless pacemaker.

Body Piercing with a Metallic Tongue Stud Resulting in Ineffective Implantable Cardioverter-defibrillator Shocks: "Heart to Mouth".

Left ventricular assist devices (LVADs) provide circulatory support to patients with severe left ventricular systolic dysfunction. Many such patients have a pre-existing implantable cardioverter-defibrillator (ICD) at the time of their LVAD surgery. LVAD implantation can alter the ICD lead parameters, including R-wave sensing, right ventricular capture threshold, and impedance. These changes can in turn affect the ability of the ICD to successfully treat malignant ventricular arrhythmias. In most patients who present with ineffective ICD shocks, the failed shock is assumed to be secondary to the patient's severe cardiomyopathy. Especially, the role of physical examination in such patients is often minimized. In our patient, a thorough history-taking and history-guided physical examination led us to the root cause of the failed ICD shocks. Our patient was noted to have a metal tongue piercing, which was the likely cause of his ineffective ICD shocks. Our case highlights the importance of a comprehensive history-taking and physical examination.

Cryoballoon Ablation for Persistent Atrial Fibrillation in a Patient with a Left Pneumonectomy.

Pulmonary vein (PV) isolation (PVI) is the most important component of catheter ablation of atrial fibrillation (AF) and can be achieved by radiofrequency or cryoballoon ablation (CBA). The CBA system has shown excellent efficacy and safety in a number of clinical trials and is independent of the PV anatomy. However, pneumonectomy can significantly alter the anatomy posing a challenge to CBA. Few cases of PVI accomplished by CBA have been described in patients with lobectomy, but none in the pneumonectomy population. We describe a case of successful CBA for paroxysmal AF in a patient with a left total pneumonectomy.

The combination of coronary sinus ostial atresia/abnormalities and a small persistent left superior vena cava-Opportunity for left ventricular lead implantation and unrecognized source of thromboembolic stroke.

BACKGROUND: Coronary sinus (CS) ostial atresia/abnormalities prevent access to the CS from the right atrium (RA) for left ventricular (LV) lead implantation. Some patients with CS ostial abnormalities also have a small persistent left superior vena cava (sPLSVC). OBJECTIVE: The purpose of this study was to describe CS ostial abnormalities and sPLSVC as an opportunity for LV lead implantation and unrecognized source of stroke. METHODS: Twenty patients with CS ostial abnormalities and sPLSVC were identified. Clinical information, imaging methods, LV lead implantation techniques, and complications were summarized. RESULTS: Forty percent had at least 1 previously unsuccessful LV lead placement. In 70%, sPLSVC was identified by catheter manipulation and contrast injection in the left brachiocephalic vein, and in 30% by levophase CS venography. In 30%, sPLSVC was associated with drainage from the CS into the left atrium (LA). When associated with CS ostial abnormalities, the sPLSVC diameter averaged 5.6 ± 3 mm. sPLSVC was used for successful LV lead implantation in 90% of cases. In 80%, the LV lead was implanted down sPLSVC, and in 20%, sPLSVC was used to access the CS from the RA. Presumably because of unrecognized drainage from the CS to the LA, 1 patient had a stroke during implantation via sPLSVC. CONCLUSION: When CS ostial abnormalities prevent access to the CS from the RA, sPLSVC can be used to successfully implant LV leads. In some, the CS partially drains into the LA and stroke can occur spontaneously or during lead intervention. It is important to distinguish sPLSVC associated with CS ostial abnormalities from isolated PLSVC.

Irrigated radiofrequency catheter ablation guided by electroanatomic mapping for recurrent ventricular tachycardia after myocardial infarction: the multicenter thermocool ventricular tachycardia ablation trial.

BACKGROUND: Recurrent ventricular tachycardia (VT) is an important cause of mortality and morbidity late after myocardial infarction. With frequent use of implantable cardioverter-defibrillators, these VTs are often poorly defined and not tolerated for mapping, factors previously viewed as relative contraindications to ablation. This observational multicenter study assessed the outcome of VT ablation with a saline-irrigated catheter combined with an electroanatomic mapping system. METHODS AND RESULTS: Two hundred thirty-one patients (median LV ejection fraction, 0.25; heart failure in 62%) with recurrent episodes of monomorphic VT (median, 11 in the preceding 6 months) caused by prior myocardial infarction were enrolled. All inducible monomorphic VTs with a rate approximating or slower than any spontaneous VTs were targeted for ablation guided by electroanatomic mapping during sinus rhythm and/or VT. Patients were not excluded for multiple VTs (median, 3 per patient) or unmappable VT (present in 69% of patients). Ablation abolished all inducible VTs in 49% of patients. The primary end point of freedom from recurrent incessant VT or intermittent VT after 6 months of follow-up was achieved for 123 patients (53%). In 142 patients with implantable cardioverter-defibrillators before and after ablation for intermittent VT who survived 6 months, VT episodes were reduced from a median of 11.5 to 0 (P<0.0001). The 1-year mortality rate was 18%, with 72.5% of deaths attributed to ventricular arrhythmias or heart failure. The procedure mortality rate was 3%, with no strokes. CONCLUSIONS: Catheter ablation is a reasonable option to reduce episodes of recurrent VT in patients with prior myocardial infarction, even when multiple and/or unmappable VTs are present. This population remains at high risk for death, warranting surveillance and further study.

Goose neck snare for LV lead placement in difficult venous anatomy.

Venous anatomy frequently impairs placement of the left ventricular (LV) lead. In some cases, the wire will not advance into the vein and in others wire position is lost as the lead is advanced. This article describes how a commonly available goose neck snare is used to gain access to the distal end of the wire as it re-enters the coronary sinus retrograde via collaterals through an adjacent vein. The snare is advanced into the coronary sinus through the same catheter as the wire. The snare opens perpendicular to the long axis of the coronary sinus due to which the wire must pass through the open loop, provided the diameter of the snare is approximately the same as the coronary sinus. Thus no time-consuming manipulation of the snare is required. With access to both ends of the wire the vein is approached either retrograde (over the distal end) or antegrade (over the proximal end) while the other end of the wire is secured by the operator. Gaining control of both ends of the wire with a snare is another example of adapting interventional techniques for the device implantation. Unlike venoplasty, the snare does not evoke credentialing concerns and can be easily implemented by most implanting physicians.

Challenging Implants Require Tools and Techniques Not Tips and Tricks.

The EP Clinics article "How to implant CRT devices in a busy clinical practice" describes the basics of the "interventional telescoping technique". This article focuses on specific circumstances where the tools and techniques are invaluable: (1) inability to locate the coronary sinus (CS), (2) inability to advance a catheter into the CS, (3) patients with CS atresia, (4) unstable CS access, (4) angulated target veins, (5) small and/or tortuous target veins, (6) target veins into which a wire cannot be advanced, (7) target veins with a drain pipe takeoff, (8) target veins close to the CS ostium.

Implant venoplasty: dilation of subclavian and coronary veins to facilitate device implantation: indications, frequency, methods, and complications.

Subclavian vein (SV) obstruction occurs in 13-35% of patients with prior leads, resulting in use of proximal venous access, the other vein, laser lead extraction, or surgery. Surgery is required for optimal left ventricle lead placement in 10-15% of cardiac resynchronization therapy candidates because of small or stenotic veins. Published data describe the safe and successful balloon dilation of both subclavian and coronary veins (CV); however, implant venoplasty is rarely performed because many implanting physicians are not familiar with the use of balloons. This article outlines how we use venoplasty to facilitate implantation in our laboratory. The indications, frequency, observed and potential complications that have evolved with our experience are also discussed.

Coronary vein rupture during venoplasty for LV lead placement.

Coronary vein rupture is a potential complication of venoplasty for LV lead placement. Vein rupture in a patient with a virgin pericardium would be anticipated to have a profound hemodynamic impact from bleeding into the pericardial space. This report describes an elderly woman with a virgin pericardial space who underwent cardiac resynchronization therapy (CRT). Venoplasty of a lead limiting venous stenosis was performed on the lateral coronary vein. The stenosis was unresponsive to a standard noncompliant balloon with side wire. When the inflation pressure was increased beyond the rated burst pressure the balloon ruptured, perforating the vein. We describe our experience in successfully placing the left ventricular lead safely despite the problems arising from these circumstances.

Focused force coronary venoplasty to eliminate a refractory stenosis preventing LV lead placement in two patients.

This report describes two patients who underwent a second attempt at cardiac resynchronization therapy (CRT) in the setting of a severe stenosis in the lateral coronary vein that prevented passage of a left ventricular lead. Both stenoses were unresponsive to standard noncompliant balloon dilatation but were successfully treated with the addition of a second stiff angioplasty wire beside the noncompliant balloon. Venoplasty with the addition of a side wire beside the balloon should be considered for resistant coronary vein stenosis encountered during CRT device implantation.

Over the wire lead extraction and focused force venoplasty to regain venous access in a totally occluded subclavian vein.

INTRODUCTION: Venoplasty allows the addition or replacement of leads despite subtotal or total subclavian occlusion. METHODS: The threshold of the LV pacing lead implanted for biventricular pacing over a period of 18 months increased to greater than 5 V. A pre implant venogram revealed total subclavian occlusion. Venous access was maintained by extraction of the 4 F LV lead over a wire. Subsequently the sheath would not advance despite 6mm balloon inflation to 30 atm with no residual waist. A wire was placed beside the balloon and the balloon was reinflated. RESULTS: The subclavian obstruction was eliminated without damage to the existing leads. CONCLUSION: The obstruction formed by the fibrous track around an extracted lead may persist despite what appears to be successful balloon dilation. Inflation with a wire beside the balloon increases the effect eliminating the resistant obstruction without damaging the leads.

Venous System Interventions for Device Implantation.

Subclavian obstruction is common after lead implantation and the need to add or replace a lead is increasing. Subclavian venoplasty (SV) is a safe and effective option for venous occlusion. Peripheral venography overestimates the severity of the obstruction. A wire can usually be advanced into the central circulation for SV. Compared with dilators, SV improves the quality of venous access, providing unrestricted catheter manipulation for His bundle pacing and left ventricular lead implantation. SV preserves venous access and reduces lead burden. SV can easily be added to the implanting physicians lead management options.