The atrial arrhythmia profile during inferior wall acute myocardial infarction (AMI) has not been systematically examined with respect to right ventricular (RV) involvement. To this end, 62 consecutive patients with first inferior wall AMI and no other conditions known to increase susceptibility for rhythm disturbances were studied by 24-hour Holter monitoring during the first and tenth day of ...

A protected ectopic focus created in tissue excised from one heart was allowed to interact with the activity of the intact heart of another animal. The protected focus consisted of a Purkinje fiber in which a narrow central zone was rendered inexcitable. The model permitted us to study parasystole, modulated parasystole, reentry, and tachycardia in the same preparation. At moderate levels of el...

BACKGROUND Measuring postpacing intervals (PPIs) is the standard maneuver for localizing reentrant tachycardia circuits. However, changes or termination of the tachycardia during entrainment pacing, or difficulties in defining the correct local activity, limit the use of PPIs. METHODS AND RESULTS We hypothesized that the number of pacing stimuli needed to entrain (NNE) was useful for mapping ...

A 41-year-old man had chronic, recurrent, drug-resistant paroxysmal right atrial tachycardia. Electrophysiologic studies revealed features suggesting atrial reentrance, including induction and termination of tachycardia with rapid atrial pacing and atrial extrastimuli. Endocardial catheter mapping localized the origin of tachycardia to the right atrial appendage. Intraoperative epicardial mappi...

BACKGROUND The pulmonary veins (PVs) are important in the pathophysiology of atrial fibrillation (AF), as is atrial tachycardia (AT) remodeling. The relative importance of AT remodeling in PVs versus other atrial sites is unknown. The present study assessed AT-induced cellular changes in PVs versus left atrium (LA) and their relationship to arrhythmogenesis. METHODS AND RESULTS We studied ion...

Proc (Bayl Univ Med Cent) 2012;25(2):159–160 A n obese (height, 62 inches; weight, 252 lb; body mass index, 46.2 kg/m2) 54-year-old woman with longstanding asthma and chronic cigarette smoking came to the hospital with an acute asthma attack manifested by dyspnea, wheezing, and chest tightness. Her electrocardiogram showed an irregular atrial tachycardia (114 P waves/minute) with multiple P-wav...

Supraventricular arrhythmias are relatively common, often persistent, and rarely life-threatening cardiac rhythm disturbances that arise from the sinus node, atrial tissue, or junctional sites between the atria and ventricles. The term "supraventricular arrhythmia" most often is used to refer to supraventricular tachycardias and atrial flutter. The term "supraventricular tachycardia" commonly r...

Reciprocal beats between sinus node and atrium were studied in isolated rabbit heart tissue by microelectrode techniques. Early premature atrial responses which entered the sinus node frequently emerged to re-excite the atrium as "echoes." When the premature atrial beats discharged some but not all nodal areas, the atrial echoes, in turn, appeared to re-enter the sinus node. Repetitive reciproc...

BACKGROUND A comprehensive evaluation of postoperative arrhythmias following surgery for congenital heart disease by continuous Holter monitoring has not been carried out. We aimed, firstly, to establish the time course of pre- and early postoperative arrhythmias by beat-to-beat analysis following cardiopulmonary bypass and, secondly, to examine which surgical procedures present risk factors fo...

Twenty-one patients with atrioventricular (AV) bypass tracts underwent electrophysiologic studies. The bypass tract was left-sided in 15 patients, septal in five and right-sided in one patient. Orthodromic AV-reciprocating tachycardia was induced in all 21 patients, with a mean tachycardia cycle length of 342 59 msec. The introduction of single stimuli in the high right atrium during tachycardi...