Autopsy Analysis of the Implantation Site of a Permanent Selective Direct His Bundle Pacing Lead

Abstract

T o date, there has not been direct visualization of the anatomic location of direct His bundle pacing (DHBP) leads in the human heart. The absence of such data has contributed to disagreement about the location of DHBP leads with respect to the plane of the tricuspid valve. 1,2 We present an autopsy study of a patient who had previously had a DHBP lead implanted, showing unequivocally that the lead is implanted on the atrial side of the tricuspid annulus.An 81-year-old man with diabetes died of sepsis secondary to a lower-extremity infection. Two years prior, the patient presented with symptoms of congestive heart failure and presyncope. He had a history of coronary artery bypass graft and myocardial infarction with mild to moderate left ventricular dysfunction (ejection fraction, 40%-45%). ␤-blockade therapy was limited by sinus bradycardia and frequent Wenckebach block. The patient was noninducible for ventricular arrhythmias, and a pacemaker was recommended for chronotropic incompetence and AV block. To prevent pacemaker-induced electric dyssynchrony, we implanted a DHBP lead.DHBP lead implantation was performed as previously described. 3 Briefly, an octapolar mapping catheter was Figure 1. Electrograms obtained at the time of lead implant. Shown from top to bottom are the surface ECG leads, the DHBP pacing lead bipolar electrogram, and the octapolar mapping catheter (HBD-distal electrode bipole to HB4 -proximal electrode bipole), respectively. Left panel: Sinus rhythm. A distinct His deflection is evident on the DHBP lead and distal octapolar bipolar electrograms (HV interval, 55 ms; QRS duration, 95 ms). The low-amplitude, but discrete His potential, on the DHBP lead is indicated by the arrow. This was the fifth site tested. It is not unusual to see the bipolar His potential diminish in stature on the DHBP lead, presumably because of tissue edema following multiple serial lead fixations. Right panel: Selective direct His bundle pacing. The stimulus-to-QRS interval is isoelectric in all surface leads and equals the HV interval (55 ms). The QRS duration is identical to the conducted QRS. The arrow indicates late septal activation following His Purkinje spread.

Feasibility and effect of para-right bundle branch pacing in patients with atrial fibrillation and complete atrioventricular block

“…First, the actual operation is relatively complex and the implantation technique is challenging. Second, autopsy analysis of the implantation site of direct His-bundle pacing has shown unequivocally that the pacing lead is implanted on the atrial side of the tricuspid annulus [14]. In fact, the implantation lead on this site had a poor sensed ventricle signal.…”

“…In fact, the implantation lead on this site had a poor sensed ventricle signal. Therefore, a backup lead should be inserted into RV to ensure an adequate ventricular sensing [14]. Third, for patients of AVB with the blocking site at the distal His-bundle, direct His-bundle pacing is not a proper choice.…”

Step-wise Approach to Permanent His Bundle Pacing

“…In most cases, the pacing site is supravalvular where higher outputs might generate non-selective capture of the His bundle, with lower outputs generating selective capture (Video 1 and Figure 3). 10,11 The QRS with selective capture will be essentially identical to native conduction, whereas nonselective QRS morphology will have a characteristic pseudo-delta wave akin to pre-excitation associated with an anteroseptal pathway. If the His pacing site is subvalvular, His capture is more likely to be encountered at higher outputs (resulting in non-selective His bundle capture, described elsewhere 4,9,12 and below), with lower output resulting in ventricular capture only prior to loss of capture (Video 2 and Figure 4).…”

Fundamental Concepts in Electrophysiology in Cases and Reviews

“…Although rare, dronedarone can cause severe liver toxicity, and monitoring is warranted. 30 Arrhythmia management devices have not only improved outcomes for patients with arrhythmias, but also provided substantial insights into pathophysiology. Correa de Sa et al describe an anatomic study of a patient who had effective, chronic His bundle pacing for 2 years and at autopsy the lead position could be directly examined and related to the anatomy of the conduction system.…”

“…Correa de Sa et al describe an anatomic study of a patient who had effective, chronic His bundle pacing for 2 years and at autopsy the lead position could be directly examined and related to the anatomy of the conduction system. 30 …”