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

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

Journal of Innovations in Cardiac Rhythm Management, 2019

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.

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.

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

Overdrive suppression of implanted pacemakers in patients with AV block

Heart, 1978

Patients being permanently paced for symptomatic AV block were studied by overdrive suppression of the QRS-inhibited pacemaker, in order to observe the underlying heart rhythm. The chest wall stimulation method was used. In complete AV block the escape rhythm recovery time proved highly reproducible on repeated testing on the same day, and in many patients remained so over months or years. Occasionally, a doubling of the escape rhythm recovery time was seen, suggesting initial exit block of the escape focus. Resetting of the escape rhythm usually followed an exponential curve until stabilisation after about 3 minutes. An early escape rhythm with a recovery time of less than 4 seconds was found on every occasion in 21 of 58 patients with complete AV block, and inconstantly in 23 more; in 14 it was never observed. Accidental pacing failure was seen in 15 patients. The overdrive suppression test was helpful in selecting pacemaker dependent patients.

Atrio-Ventricular and Ventriculo-Atrial Conduction Times in Patients Undergoing Pacemaker Implant

Pacing and Clinical Electrophysiology, 1983

Hy\VES, D.L. AND FURMAN, S.: Atrio-ventricular and ventriculo-atrial conduction times in patients undergoing pacemaker implant. Pacemaker mediated reentrant tachycardias have been seen frequently during use 0/ dual chamber sensing pacemakers and are dependent on the presence of intact retrograde (ventriculo-atrial] conduction. The status of a patient's retrograde (VA) conduction cannot be deferminedfrom fhe surface electrocardiogram. At the time of pacemaker implant the state of antegrade conduction should be determined at incremental atrial pacing rates, the exact timing measured from the intracardiac electrograms, i.e., from the intrinsic deflection of the atrium to the intrinsic deflection of the ventricle. With this information obtained in 53 patients, it was possible to determine which patients could safely receive dual chamber sensing pacemaker devices, the appropriate pacemaker atriai refractory period setting to avoid pacemaker mediated tachycardias in those patients with intuct retrograde conduction, and the optimal timing for programming the pacemaker's AV delay. Patients who have been studied in this manner and who were felt to be suitable for a dual chamber sensing device have not displayed pacemaker mediated reentrant tachycardias. Forty-seven percent of all patients who require pacemaker impiant have VA 1:1 conduction: 67% of those with sinus node dysfunction and lVA. of those with complete antegrade bJock have VA conduction at a mean interval of 235 ± 5d ms (range 110-380

Diagnostic Approach to Narrow Complex Tachycardia with VA Block

Pacing and Clinical Electrophysiology, 1997

HAMDAN, M.H., ET AL.: Diagnostic Approach to Narrow Complex Tachycardia with VA Block. Narrow complex tachycardia with VA block is rare. The differential diagnosis usually con. 'iists of (1) junctional tachycardia (JT) with retrograde block: (2) A V nodal reentrant tachycardia (A VNRT) with proximal common pathway block; and finally (3) nodofascicular tachycardia using the His-Purkinje system for antegrade conduction and a nodofascicular pathway for retrograde conduction. Analysis of tachycardia onset and termination, the effect of bundle branch block on tachycardia cycle length, and the response to atrial and ventricular premature depolarization must be carefully done. Making the correct diagnosis is crucial as the success rate in eliminating the tachycardia will depend on tachycardia mechanism. (PACE 1997: 20[Pt. I]:2984~2988)

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,