Dispersion of monophasic action potential duration: demonstrable in humans after premature ventricular extrastimulation but not in steady state.

Abnormal dispersion of repolarization may contribute to the arrhythmogenic physiologic substrate of ventricular arrhythmia. Geographic dispersion of monophasic action potential duration was determined in steady state (drive cycle lengths 600 and 430 ms) between widely spaced right ventricular endocardial sites (geographic dispersion) in 10 control patients with right ventricular disease and complicating ventricular tachycardia (n = 9), 6 patients with right and left ventricular disease and complicating ventricular tachycardia and 7 patients with ischemic heart disease and complicating ventricular tachycardia. No significant difference in geographic dispersion could be demonstrated among the groups. Difference of monophasic action potential duration at adjacent right ventricular endocardial sites (adjacent dispersion) was determined after ventricular extrastimulation during construction of simultaneous electrical restitution curves in the same patient groups. Maximal adjacent dispersion over the electrical restitution curve was compared between disease and control groups. There was a significant difference in observations of maximal adjacent dispersion in patients with right ventricular disease and complicating ventricular tachycardia (range 5 to 85 ms, median 22.5; 14 pairs of sites; p less than 0.05) and patients with right and left ventricular disease and complicating ventricular tachycardia (range 5 to 50 ms, median 17.5; 14 pairs of sites; p less than 0.05) compared with control patients (range 5 to 20 ms, median 10; 15 pairs of sites). This difference was not evident when patients with ischemic heart disease and complicating ventricular tachycardia (range 5 to 25 ms, median 12.5; 12 pairs of sites) were compared with control patients. Maximal percent monophasic action potential shortening from steady state was significantly greater (p less than 0.001) in both groups with greater adjacent dispersions, and prolongation of activation time at monophasic action potential recording sites after premature extrastimulation tended to be greater in patients with right or right and left ventricular disease and complicating ventricular tachycardia. It is concluded that in disease, exaggeration of monophasic action potential shortening after premature ventricular extrastimulation may contribute to the electrophysiologic arrhythmogenic substrate.

[1]  G. Moe,et al.  Nonuniform Recovery of Excitability in Ventricular Muscle , 1964, Circulation research.

[2]  M. Antz,et al.  Slow and long-lasting modulation of myocardial repolarization produced by ectopic activation in isolated rabbit hearts. Evidence for cardiac "memory". , 1989, Circulation.

[3]  B. Surawicz,et al.  Sequence of repolarization on the ventricular surface in the dog. , 1975, American heart journal.

[4]  D Durrer,et al.  Mechanism and Time Course of S‐T and T‐Q Segment Changes during Acute Regional Myocardial Ischemia in the Pig Heart Determined by Extracellular and Intracellular Recordings , 1978, Circulation research.

[5]  B. Surawicz,et al.  Effect of Premature Depolarization on the Duration of Action Potentials in Purkinje and Ventricular Fibers of the Moderator Band of the Pig Heart: ROLE OF PROXIMITY AND THE DURATION OF THE PRECEDING ACTION POTENTIAL , 1972, Circulation research.

[6]  H. Reuter,et al.  Slow recovery from inactivation of inward currents in mammalian myocardial fibres , 1974, The Journal of physiology.

[7]  D. Mirvis,et al.  Spatial variation of QT intervals in normal persons and patients with acute myocardial infarction. , 1985, Journal of the American College of Cardiology.

[8]  M R Franz,et al.  Long-term recording of monophasic action potentials from human endocardium. , 1983, The American journal of cardiology.

[9]  D. Durrer,et al.  The Effect of Acute Coronary Artery Occlusion on Subepicardial Transmembrane Potentials in the Intact Porcine Heart , 1977, Circulation.

[10]  J A Vassallo,et al.  Nonuniform recovery of excitability in the left ventricle. , 1988, Circulation.

[11]  E. Varnauskas,et al.  Further improved method for measuring monophasic action potentials of the intact human heart. , 1971, Journal of electrocardiology.

[12]  K Millar,et al.  The sequence of normal ventricular recovery. , 1972, American heart journal.

[13]  G. Moe,et al.  On the multiple wavelet hypothesis o f atrial fibrillation. , 1962 .

[14]  R. D. Steed,et al.  Evaluation of balloon aortic valvuloplasty with transesophageal echocardiography. , 1988, American heart journal.

[15]  M. Laurent,et al.  Critical analysis of cineangiographic criteria for diagnosis of arrhythmogenic right ventricular dysplasia. , 1988, American heart journal.

[16]  B. Horáček,et al.  QT interval variability on the body surface. , 1984, Journal of electrocardiology.

[17]  B. R. Jewell,et al.  A study of the factors responsible for rate‐dependent shortening of the action potential in mammalian ventricular muscle. , 1978, The Journal of physiology.

[18]  M R Franz,et al.  A new single catheter technique for simultaneous measurement of action potential duration and refractory period in vivo. , 1990, Journal of the American College of Cardiology.

[19]  W. Mckenna,et al.  Right ventricular abnormalities in ventricular tachycardia of right ventricular origin: relation to electrophysiological abnormalities. , 1986, British heart journal.

[20]  S. Olsson,et al.  Right Ventricular Monophasic Action Potentials in Healthy Young Men , 1984, Pacing and clinical electrophysiology : PACE.

[21]  F. Morady,et al.  Identification and catheter ablation of a zone of slow conduction in the reentrant circuit of ventricular tachycardia in humans. , 1988, Journal of the American College of Cardiology.

[22]  S. Olsson,et al.  Clinical electrophysiologic study of antiarrhythmic properties of flecainide: acute intraventricular delayed conduction and prolonged repolarization in regular paced and premature beats using intracardiac monophasic action potentials with programmed stimulation. , 1981, American heart journal.

[23]  M. Boyett,et al.  Changes in the electrical activity of dog cardiac Purkinje fibres at high heart rates. , 1984, The Journal of physiology.

[24]  D. Wyse,et al.  Programmed electrical stimulation studies for ventricular tachycardia induction in humans. I. The role of ventricular functional refractoriness in tachycardia induction. , 1986, Journal of the American College of Cardiology.

[25]  M. Franz,et al.  Monophasic action potential mapping in human subjects with normal electrocardiograms: direct evidence for the genesis of the T wave. , 1987, Circulation.

[26]  B. Surawicz,et al.  Dispersion of ventricular repolarization and arrhythmia: study of two consecutive ventricular premature complexes. , 1985, Circulation.

[27]  Olsson Sb Right ventricular monophasic action potentials during regular rhythm. A heart catheterization study in man. , 1972 .

[28]  B. Singh,et al.  Ionic mechanisms in heart muscle in relation to the genesis and the pharmacological control of cardiac arrhythmias. , 1978, Pharmacological reviews.

[29]  B. G. Bass Restitution of the action potential in cat papillary muscle. , 1975, The American journal of physiology.

[30]  V. Bonatti,et al.  Recording of monophasic action potentials of the right ventricle in long QT syndromes complicated by severe ventricular arrhythmias. , 1983, European heart journal.

[31]  C J Griffiths,et al.  Sequence of epicardial repolarisation and configuration of the T wave. , 1988, British heart journal.

[32]  H. Wellens,et al.  Observations on Mechanisms of Ventricular Tachycardia in Man , 1976, Circulation.

[33]  P M Rautaharju,et al.  Ventricular action potentials, ventricular extracellular potentials, and the ECG of guinea pig. , 1985, Circulation research.

[34]  B. Surawicz,et al.  Characteristics and Possible Mechanism of Ventricular Arrhythmia Dependent on the Dispersion of Action Potential Durations , 1983, Circulation.