Jess W. Oren

Intravascular Extraction of Problematic or Infected Permanent Pacemaker Leads: 1994–1996

Of the 400,000–500,000 permanent pacemaker leads implanted worldwide each year, around 10% may eventually fail or become infected, becoming potential candidates for removal. Intravascular techniques for removing problematic or infected leads evolved over a 5‐year period (1989–1993). This article analyzes results from January 1994 through April 1996, a period during which techniques were fairly stable. Extraction of 3,540 leads from 2,338 patients was attempted at 226 centers. Indications were: infection (27%), nonfunctional or incompatible leads (25%), Accufix® or Encor® leads (46%), or other causes (2%). Patients were 64 ± 17 years of age (range 5–96); 59% were men, 41% women. Leads were implanted 47 ± 41 months (maximum 26 years), in the atrium (53%), ventricle (46%), or SVC (1%). Extraction was attempted via the implant vein using locking stylets and dilator sheaths, and/or transfemorally using snares, retrieval baskets, and sheaths. Complete removal was achieved for 93% of leads, partial for 5%, and 2% were not removed. Risk of incomplete or failed extraction increased with implant duration (P < 0.0001), less experienced physicians (P < 0.0001), ventricular leads (P < 0.005), noninfected patients (P < 0.0005), and younger patients (P < 0.0001). Major complications were reported for 1.4% of patients (< 1% at centers with > 300 cases), minor for 1.7%. Risk of complications increased with number of leads removed (P < 0.005) and with less experienced physicians (P < 0.005); risk of major complications was higher for women (P < 0.01). Given physician experience, appropriate precautions, and appropriate patient selection, contemporary lead removal techniques allow success with low complication rates.

Permanent His-bundle pacing is feasible, safe, and superior to right ventricular pacing in routine clinical practice

BACKGROUND Right ventricular pacing (RVP) has been associated with heart failure and increased mortality. His-bundle pacing (HBP) is more physiological but requires a mapping catheter or a backup right ventricular lead and is technically challenging. OBJECTIVE We sought to assess the feasibility, safety, and clinical outcomes of permanent HBP in an unselected population as compared to RVP. METHODS All patients requiring pacemaker implantation routinely underwent attempt at permanent HBP using the Select Secure (model 3830) pacing lead in the year 2011 delivered through a fixed-shaped catheter (C315 HIS) at one hospital and RVP at the second hospital. Patients were followed from implantation, 2 weeks, 2 months, 1 year, and 2 years. Fluoroscopy time (FT), pacing threshold (PTh), complications, heart failure hospitalization, and mortality were compared. RESULTS HBP was attempted in 94 consecutive patients, while 98 patients underwent RVP. HBP was successful in 75 patients (80%). FT was similar (12.7 ± 8 minutes vs 10 ± 14 minutes; median 9.1 vs 6.4 minutes; P = .14) and PTh was higher in the HBP group than in the RVP group (1.35 ± 0.9 V vs 0.6 ± 0.5 V at 0.5 ms; P < .001) and remained stable over a 2-year follow-up period. In patients with >40% ventricular pacing (>60% of patients), heart failure hospitalization was significantly reduced in the HBP group than in the RVP group (2% vs 15%; P = .02). There was no difference in mortality between the 2 groups (13% in the HBP group vs 18% in the RVP group; P = .45). CONCLUSION Permanent HBP without a mapping catheter or a backup right ventricular lead was successfully achieved in 80% of patients. PTh was higher and FT was comparable to those of the RVP group. Clinical outcomes were better in the HBP group than in the RVP group.

PERMANENT HIS BUNDLE PACING IS FEASIBLE AND SUPERIOR TO RIGHT VENTRICULAR PACING IN ROUTINE CLINICAL PRACTICE

Right Ventricular pacing (RVP) has been associated with ventricular dyssynchrony, heart failure (HF) and increased mortality. His Bundle pacing (HBP) is a more physiological alternative but requires a mapping catheter, a back-up RV lead and can be technically challenging. We compared procedural and

A novel approach to differentiating orthodromic reciprocating tachycardia from atrioventricular nodal reentrant tachycardia

BACKGROUND Various diagnostic maneuvers have been proposed to help differentiate orthodromic reciprocating tachycardia (ORT) from atrioventricular nodal reentrant tachycardia (AVNRT) prior to ablation. However, not all criteria are applicable in every situation as each has limitations. OBJECTIVE The purpose of this study was to determine whether the behavior of tachycardia during onset of right ventricular (RV) pacing would help differentiate ORT from AVNRT. METHODS We retrospectively reviewed 72 cases (42 typical AVNRT, 7 atypical AVNRT, 15 left free-wall pathways, 6 septal pathways, 2 right free-wall pathways). We assessed the number of beats required to accelerate the tachycardia cycle length (TCL) to the paced cycle length (PCL) once a fully RV paced complex was achieved during supraventricular tachycardia. RESULTS In the AVNRT group, delta cycle length (DCL = PCL-TCL) was 29 +/- 16 ms compared to 29 +/- 10 ms in ORT group (P = NS). In the AVNRT group, the average number of fully RV paced beats required to reset the tachycardia was 3.7 +/- 1.1 compared to 1 +/- 0 in the ORT group (P <.0001). Using a cutoff >1 beat yielded both positive and negative predictive values of 100% for diagnosing AVNRT versus ORT. During entrainment attempts, AVNRT terminated 51% of the time and ORT terminated 65% of the time but still allowed application of the new criterion. CONCLUSION Assessing timing and type of response of supraventricular tachycardia to RV pacing can help differentiate ORT from AVNRT with high certainty and prevent the need for other pacing maneuvers and measurements.

Permanent His Bundle Pacing: Long-Term Lead Performance and Clinical Outcomes

BACKGROUND Right ventricular pacing (RVP) is associated with heart failure and increased mortality. His-bundle pacing (HBP) is a physiological alternative to RVP. OBJECTIVE The purpose of this study was to report long-term performance and compare the clinical outcomes of permanent HBP vs RVP. METHODS All patients requiring pacemaker implantation underwent an attempt at permanent HBP in 2011 at one hospital and RVP at the sister hospital. Patients were followed from implantation, 2 weeks, 2 months, and yearly for 5 years. Left ventricular ejection fraction (LVEF), pacing thresholds, lead revision, and generator change were tracked. Primary outcome was the combined endpoint of death or heart failure hospitalization (HFH) at 5 years. RESULTS HBP was attempted in 94 consecutive patients and was successful in 75 (80%); 98 patients underwent RVP. LVEF remained unchanged in the HBP group (55% ± 8% vs 57% ± 6%; P = .13), whereas significant decline was noted in the RVP group (57% ± 7% vs 52% ± 11%; P = .002). Incidence of pacing-induced cardiomyopathy was significantly lower in HBP compared to RVP patients (2% vs 22%; P = .04). At 5 years, death or HFH was significantly lower in HBP compared to RVP patients with >40% ventricular pacing (32% vs 53%; hazard ratio 1.9; P = .04). At 5 years, the need for lead revisions (6.7% vs 3%) and for generator change (9% vs 1%) were higher in the HBP group. CONCLUSION In patients undergoing pacemaker implantation, permanent HBP was associated with reduction in death or HFH during long-term follow-up compared to RVP. HBP was associated with higher rates of lead revisions and generator change.

Successful use of wearable cardioverter defibrillator in a patient with dextrocardia and persistent left superior vena cava.

Congenital disorders, such as dextrocardia and persistent left superior vena cava, are rare. However, their presence is often associated with other cardiac anomalies, and may lead to lethal ventricular tachyarrhythmias, which result in sudden cardiac death. Treating patients with these disorders can present a challenge to clinicians, as it may cause technical difficulties during interventional procedures, and more often, altered defibrillation techniques in a setting of prehospital sudden cardiac arrest. This report describes the first case of successful defibrillation therapy delivered by the wearable cardioverter defibrillator to a patient with dextrocardia and persistent left superior vena cava during a ventricular tachycardia arrest.

Reply: 50 Years From Bench to Bedside: His Bundle Pacing Versus Right Ventricular Apical Pacing

We thank Drs. Scherlag and Elkholey for their interest in our study [(1)][1]. Right ventricular endocardial pacing has been the standard ventricular pacing site for >5 decades. Even though Wiggers [(2)][2] reported on the physiological observations identifying the abnormal ventricular function