Mapping and Ablation of Retrograde Conduction During a Nearly Incessant Pacemaker-mediated Tachycardia in a Patient with Third-degree Atrioventricular Block (original) (raw)

Tachycardia after pacemaker implantation in a patient with complete atrioventricular block

Europace, 2007

The atrioventricular (AV) node allows ante-and retrograde conduction between atria and ventricles. It is commonly assumed that these AV nodal conduction properties go hand in hand. However, ante-and retrograde AV conduction can be completely independent from each other in individual patients. We report about a patient with permanent AV block III8 requiring implantation of a pacemaker. As soon as a dual-chamber device was connected to the implanted leads, a tachycardia started at the maximum tracking rate, which was subsequently reprogrammed from 120 to 170 bpm. Non-invasive electrophysiologic testing showed that this patient demonstrated 1:1 ventriculoatrial (VA) conduction up to 170 bpm leading to endless loop tachycardia (ELT) while the antegrade AV block III8 persisted. This case impressively illustrates that one has to take into account that patients with antegrade AV block III8 may still have a high VA conduction capacity leading to ELT. Dual-chamber devices therefore have to be programmed accordingly, activating dedicated reactions after ventricular premature beats and automatic ELT detection and termination algorithms.

Ventriculoatrial conduction and related pacemaker-mediated arrhythmias in patients implanted for atrioventricular block: An old problem revisited

International Journal of Cardiology, 2013

Introduction: Ventriculoatrial (VA) conduction and related pacemaker-mediated tachyarrhythmias (PMT) have not been systematically investigated in a large cohort of patients implanted for symptomatic atrioventricular (AV) block. Methods and results: Two hundred fifty consecutive patients (71 ± 14 years, 63% male) implanted for symptomatic second-or third-degree AV block were screened for retrograde VA conduction and related PMTs including endless loop tachycardia (ELT) and repetitive nonreentrant VA synchrony (RNRVAS). After a mean post-implantation period of 38 ± 12 months, AV block was persistent in 137 (55%) and variable in 113 (45%) patients. Retrograde 1:1 conduction was present in 76 patients (30%) with a mean VA conduction time of 258 ± 65 ms. The incidence of VA conduction varied considerably according to the presence and type of anterograde conduction block. Retrograde conduction was present in 24 of 137 patients (18%) with persistent AV block. Fifteen of the 76 patients (20%) with VA conduction had ≥1 documented PMT. The recorded arrhythmias were ELT in 11 and RNRVAS in 4 patients. VA conduction time was significantly longer in patients with than without PMT (297 ± 64 vs. 249 ± 62 ms, resp., P b 0.01). None of the patients without VA conduction had documented PMTs. Conclusions: Retrograde VA conduction and related PMTs are not uncommon in patients implanted for symptomatic AV block. Testing for retrograde conduction should therefore be performed in all patients with AV block in order to optimize device programming and prevent PMTs.

Induction of transient third degree atrioventricular block during radiofrequency catheter ablation in a patient with ventricular tachycardia and remote myocardial infarction

European Heart Journal, 1995

Patients with third-degree atrioventricular block implanted with a dual-chamber pacemaker in DDD mode can develop pacemaker-mediated tachycardias if retrograde ventriculoatrial (VA) conduction is present. Programming a long post-VA refractory period to avoid tachycardia initiation can be contraindicated if these patients have a good atrial response from exercise testing and require a high maximum tracking rate to allow for a proper response to sensed atrial rhythms. We report a case of a patient in whom mapping and ablation of retrograde conduction during the pacemaker-mediated rhythm was the only solution to allow both the programming of a high tracking rate and the elimination of tachycardia induction.

Pacemaker‐mediated tachycardia in the absence of retrograde ventriculoatrial conduction: What is the mechanism?

Journal of Cardiovascular Electrophysiology, 2018

A 49-year-old man with a complex congenital heart disease (comprising dextrocardia with situs solitus, atrial septal defect, ventricular septal defect, severe pulmonary stenosis and D-transposition of the great arteries surgically repaired by means of the Rastelli procedure at the age of 22 years) underwent single-chamber defibrillator (ICD) implantation for primary prevention of sudden cardiac death due to severe systolic dysfunction of the systemic ventricle. The right ventricular lead (RV; Durata 7120, St. Jude Medical TM, Sylmar, CA, US) was implanted using a conventional transvenous approach. Two years later the patient developed heart failure symptoms and the ECG showed sinus rhythm with first degree AV block and left bundle branch block QRS morphology. Therefore, upgrade to cardiac resynchronization therapy (Unify 3235-40Q CRT-D, St Jude Medical TM, Sylmar, CA, US) was performed in 2012. Two epicardial leads were surgically implanted in the left atrium (LA; Miopore 511212, Greatbatch medical TM) and left ventricle (LV; 6071, Medtronic TM, Minneapolis, US). The X-ray lead positioning is shown in Figures 1A and 1B. The patient was followed by remote monitoring. Pacing and sensing parameters were stable (R wave 5.5 mV, RV threshold 1.0V at 0.5 ms; P wave 3.1 mV, LA threshold 0.75V at 0.5 ms; LV threshold: 1.75V at 0.5 ms) and no arrhythmic episodes were documented during the follow-up. The real time EGM showed a significant far-field of the ventricular signal in the atrial channel, as consequence of proximity of epicardial lead. The ventricular far-field falls in the blanking period,

Pacemaker-mediated tachycardias: a new modality of treatment

Pacing and clinical electrophysiology : PACE, 1984

Three patients with pacemaker interactive drug resistant tachycardia underwent invasive electrophysiological studies. In the first patient, the retrograde conduction of the artificial reciprocating tachycardia was provided by two right-sided accessory pathways and the antegrade conduction by an atrial synchronous pulse generator. In addition, AV-nodal tachycardia occurred alternately. In the second patient with intermittent atrial flutter, the AV node and, coincidentally, an AV sequential pulse generator provided high-rate antegrade conduction to the ventricles. In the third patient with surgical complete heart block, intermittent AV-nodal tachycardia induced retrograde atrial activation while an atrial synchronous pacemaker provided the antegrade conduction. Electrode catheter exploration of the heart allowed localization and closed-chest ablation of the accessory pathways or AV node by delivering two to seven 200-joule direct-current shocks through the appropriate electrode of the...

Catheter Ablation of Accessory Pathway in the Treatment of Pacemaker-Mediated Tachycardia

Pacing and Clinical Electrophysiology, 2012

Pacemaker-mediated tachycardia (PMT) remains a clinical problem in patients with dual-chamber pacemaker despite technological advances. The onset mechanism of this tachycardia is sensing of retrograde atrial activation after ventricular stimulation. Repeated retrograde conduction perpetuates tachycardia. Postventricular atrial refractory period prolongation has been used for prevention of PMT, but this is not the solution in all cases. We present a case with PMT where the retrograde limb is a left accessory pathway, which is treated with radiofrequency ablation successfully. (PACE 2012; 35:e74-e76)

Retrograde ventriculoatrial conduction in complete heart block

The American Journal of Cardiology, 1972

Electrophysiologic Studies During the insertion of a temporary transvenous pacemaker, bundle of His electrograms were recorded by means of a modification of the method of Damato et a1.3 Under fluoroscopic control a no. 4F bipolar electrode catheter was passed up to the right atrium by way of the right femoral vein through a no. 14 Jelco sheath introduced percutaneously. The 2 poles of the catheter were positioned near the tri