Atrial Systole and Ineffective Pacemaker Stimuli (original) (raw)
Pacing and Clinical Electrophysiology, 1985
A cause of atrial malpacing in AV universal pacemakers. A report of two cases. Hetrognid)! atrial activation during venlricuiur pocing has ojlen been a caust' of inlermiflont or persislenl arrhylhmios (pacemaker-mediated tochycardia) in AV universaJ pacemakers. We recen(/y encountered (wo cases in which VA conduction was responsibie for atrial mciJpncing in jKid'enfs with an implantf.d AV universal pncnmaker. oiw programmed in DDD and one in DVl mode. Atrial nialpacing was induced by the alrial refvactoriness due to retrograde actjvotjon. In the first patient, it was observed when the pacemaker was programmed to a rale of 110 ppm {lower rate] and an AV interval of 200 ms in order to cbeck crosstalk. In the second patient, it was observed after ventricular premature contractions.
Pacing and Clinical Electrophysiology, 1982
Pacer-induced tachycardia associated with an atriaJ synchronous ventricuiar inhibited (ASVIP) pulse generator. A 68-year-old white maJe underwent permanent pacemaker impiantation with an atrial synchronous ventricular inhibited pulse generator fMedtronic modei 2409} because of syncope and abnormal H-V interval of 70 ms. Paroxysmal bouts of pacemaker associated tachycardia were subsequently recorded on several occasions, initiated and terminated by spontaneous ventricular premature beats. The mechanism for the occurrence of the tachyarrhythmia is discussed in detail and the functional characteristics of the pulse generator are described. Replacement of the unit with a different pacer device prevented further occurrence of the arrhythmia. (PACE, Vol. 5, March-Aprii, 1982] pacer tachycardia, atriaJ synchronous pacer, pacemaker arrhythmia, programmable pacemaker, retrograde conduction The development of more stable transvenous atrial electrodes and improved surgical implantation techniques'"^ has rekindled interest in the use of dual chamber pulse generators, both for hemodynamic benefit""'" as well as antiarrhythmic effect.""'* As a result, more complex pacemaker electrocardiograms have emerged and more often than not, have posed a problem in their correct interpretation. Recently, we treated a patient who presented with an interesting pacemaker associated arrhythmia.
Atypical pacemaker-mediated tachycardia from the atrial channel: What is the mechanism?
Heart Rhythm, 2011
A 79-year-old woman with history of hypertension, dyslipidemia, obesity, bulbar stroke , and paroxysmal atrial fibrillation was evaluated for an abrupt syncope. Echocardiogram showed no abnormalities, and Holter monitoring showed sinus arrhythmia with right bundle branch block (RBBB) and signs of sick sinus syndrome due to significant pauses. A dual-chamber pacemaker was implanted without complications (ventricular electrode in the right ventricular apex and atrial electrode at the high right atrial appendage). Pacemaker settings were DDDR mode, basic rate 65 bpm, maximum sensor rate 110 bpm, maximum tracking rate 150 bpm, and dynamic AV interval of maximum 280/minimum KEYWORDS Pacemaker-mediated tachycardia; electrodes dislodgement ABBREVIATIONS ECG ϭ electrocardiogram; PMT ϭ pacemaker-mediated tachycardia; RBBB ϭ right bundle branch block (Heart Rhythm 2011;8:636 -638)
Ventricular Output Failure in a DDD Permanent Pacemaker Associated with Increased Atrial Output
Pacing and Clinical Electrophysiology, 1997
Previous reports have described the occurrence of ventricular autput failure in a permanent DDD pacemaker system related to an increase in the atrial output in the presence of low atrial lead impedance (Medtronic Synergyst®/Synergyst II®). This phenomenon is seen exclusively following atrial paced events and may potentially lead to significant bradyarrhythmia or ventricular asystole in a pacemaker dependent patient. We describe the occurrence of analogous behavior in a Medtronic Symbios® 7006 generator.
Pacemaker Stimulation Criticism at ECG
New Concepts in ECG Interpretation, 2018
Cardiac implantable electronic devices' (CIEDs) numbers have grown up worldwide over the last years [1]. At the same time, functions and algorithms' complexity implementation also expanded. It will be therefore more and more frequent for the clinician to deal with pacemaker (PM) ECGs and unusual device behaviors, particularly when they mimic pseudo-malfunctions. In this chapter, we present some examples of challenging electrocardiograms, aiming to show how the clinician, just by analyzing the ECG, could reach or at least suspect the correct diagnosis. 16.1 Case 1 An 82-year-old man with a history of systemic hypertension and previous dual-chamber PM implantation for second-degree atrioventricular (AV) block was referred to our clinic with a suspected PM malfunction. The patient was asymptomatic. ECG is shown in Fig. 16.1a, b.
An acute experimental model demonstrating 2 different forms of sustained atrial tachyarrhythmias
Circulation. Arrhythmia and electrophysiology, 2009
The objective of this study was to develop an acute experimental model showing both focal and macroreentrant sustained atrial fibrillation (AF). In 31 anesthetized dogs, bilateral thoracotomies allowed the attachment of electrode catheters at the right and left superior pulmonary veins, atrial free walls, and atrial appendages. Acetylcholine, 100 mmol/L, was applied topically to either appendage. Sequential radiofrequency ablation was achieved for the ganglionated plexi (GP), found adjacent to the 4 pulmonary veins. In 12 separate studies, a propafenone bolus, 2 mg/kg, was given before and after GP ablations at the start of acetylcholine-induced AF. Acetylcholine caused abrupt onset of AF (n=22) or induced AF by burst pacing (n=9) that lasted > or = 10 minutes. Rapid, regular, or fractionated atrial electrograms were consistently seen (average cycle length, 37+/-7 ms) at the appendages versus cycle lengths of 114+/-23 ms at other atrial sites. After ablations of GP, AF abruptly t...
Inadvertent suppression of a fixed rate ventricular pacemaker using a peripheral nerve stimulator
Anaesthesia, 1993
Electromagnetic interference usually produces only minor effects in patients with pacemakers. Nevertheless, the possibilities of serious and even fatal consequences of this complication must be recognised. This case reports an unusual anaesthetic source of interference, caused by activation of a popular nerve stimulator, resulting in cardiac arrest in a patient with a fixed-rate ventricular pacemaker.
Journal of the American College of Cardiology, 1983
A case of recurrent ventricular tachycardia produced by an asynchronous ventricular stimulus of a normally functioning "committed" atrioventricular (AV) sequential demand (DVI) pacemaker is described. The characteristics of these units are compared with those of the A variety of pacemaker-induced arrhythmias has been observed with the introduction of new cardiac pacing modes (1). With the advent of atrioventricular (AV) sequential demand (DVI) pacemakers, the electrocardiographic features associated with their normal operation have been studied and reported (2). In this report, we describe an abnormal event: the induction of ventricular tachycardia by a normally functioning DVI pacemaker.
Course of Symptoms and Spontaneous ECG in Pacemaker Patients: A 5-Year Follow-up Study
Pacing and Clinical Electrophysiology, 1988
LANGENFELD, H,, ET AL.: Course of symptoms and spontaneous ECG in pacemaker patients: A 5-year follow-up study. We investigated the course of symptoms and the spontaneous ECG retrospectiveiy in 308 patients who had received a pacemaker because of a trio ventricuJar (AV) block fn = 115), sick sinus syndrome fSSS, n = 107), bradyarrhythmic atriai jibriJiation fbradyarrhythmia, n = 51). carotid sinus syndrome (CSS, n = 16), complete bi/ascicuiar block associated with 1st degree AV block (n = 13) and with other indications fn = 6). The mean impiantation time was 63 months. The c\ir\ica\ state of 93% of all patients improved after pacemaker implantation; their symptoms decreased markedly. Persisting syncopy in some patients with SSS, however, supports a restricted implantation policy. We rarely saw improved AV conduction in patients with AV block fn%). Furthermore, in patients with SSS, afriaJ /ibriliotion occmed significantly more often (35 %) than in those with AV block (17 %; P < 0.01). Only 3% of patients with SSS developed 2nd and 3rd degree AV block within the observation period. In all patients with Initial bi/ascicular block and additional 1st degree AV block, pacing prevented further syncopaJ attacks; four of them showed 3rd degree AV block at control, indicating that pacemaker impiantation is mandatory in symptomatic patients with bifascicular disease and 1st degree AV block. (PACE, Vol. 11, December 1988) folow-up, pacemaker patients, symptoms, spontaneous ECC Address for reprints: Heiner Langenfeld. MD