Di Palma, Joseph R.
April 1960
Angiology;Apr1960, Vol. 11 Issue 2, p126
Academic Journal
In open chest anesthetized dogs the heart was driven at rates from 90 to 210 per minute with the sinuaurieular node intact or crushed. A second pulse produced a premature systole measuring the refractory period of the normal cyclic systole. A third pulse was applied producing a second premature systole so as to measure the refractory period of the first premature systole. Latency of response to the second and third pulses was also measured. It was found that in all heart rates studied, the refractory period and latency were much shorter for the premature systole as compared to the previous cyclic systole. In nodal rhythm the same results were obtained. Latency was progressively shorter for the premature systoles induced in successive cycles. The results substantiate the view that a single premature systole may make the heart muscle more susceptible to rapid ventricular rhythms.


Related Articles

  • Early afterdepolarisations and ventricular arrhythmias in cardiac tissue: a computational study. Scarle, Simon; Clayton, Richard H. // Medical & Biological Engineering & Computing;Mar2009, Vol. 47 Issue 3, p291 

    Afterdepolarisations are associated with arrhythmias in the heart, but are difficult to study experimentally. In this study we used a simplified computational model of 1D and 2D cardiac ventricular tissue, where we could control the size of the region generating afterdepolarisations, as well as...

  • An Unusual Cause Of Seizures In A 10 Year Old. Govindaraj, P.R.; Thomas, E.; Gnanapragasam, J.P. // Internet Journal of Pediatrics & Neonatology;2004, Vol. 4 Issue 1, p76 

    Seizures are a common problem in childhood. We report a 10 year old presenting with seizures caused by acute onset heart block. Although minor degrees of heart block can occur in acute myocarditis, presenting with Stokes Adams episodes because of complete heart block is extremely rare.

  • tachycardia.  // Royal Society of Medicine: Medicines;2002, p522 

    The article presents information on the heart disease tachycardia. It is an increase in the rate of heart beat above normal.

  • Concealed accessory pathways.  // Herzschrittmachertherapie und Elektrophysiologie;Mar2010, Vol. 21 Issue 1, p71 

    Concealment of an accessory pathway is caused by its ability to conduct retrogradely only. This variant of accessory pathway conduction could not be confirmed until invasive electrophysiology was introduced in the 1970s. As a rule, it is reported that concealed accessory pathways were predicted...

  • Differential role of PI3K/Akt pathway in the infarct size limitation and antiarrhythmic protection in the rat heart. Táňa Ravingerová; Jana Matejíková; Jan Neckář; Eva Andelová; FrantiÅ¡ek Kolář // Molecular & Cellular Biochemistry;Mar2007, Vol. 297 Issue 1/2, p111 

    Abstract??Endogenous cardiac protection against prolonged ischemic insult can be achieved by repeated brief episodes of ischemia (hypoxia) or by cardiac adaptation to various stresses such as chronic hypoxia. Activation of phosphatidylinositol 3-kinase (PI3K)/Akt is involved in antiapoptotic...

  • Ablation of ventricular tachycardia. Fermin Garcia; Ermengol Valles; Sandhya Dhruvakumar; Francis Marchlinski // Herzschrittmachertherapie und Elektrophysiologie;Dec2007, Vol. 18 Issue 4, p225 

    Zusammenfassung   Die Katheterablation stellt eine wichtige Therapieoption in der Behandlung ventrikulärer Arrhythmien dar. Sogar in Zentren mit spezieller Erfahrung birgt die Ablation ventrikulärer Tachykardien ein kleines, aber relevantes Komplikationsrisiko. Hierbei ist zu denken...

  • Radiofrequency Ablation for the Treatment of Atrial Fibrillation—Brief Report Update Sparks, Paul B. // Heart, Lung & Circulation;Jun2005 Supplement, Vol. 14 Issue 2, pS21 

    Considerable advances have been made in both the understanding of and the curative treatment for atrial arrhythmias over the last decade. Radiofrequency ablation of typical right atrial flutter and focal atrial tachycardia using standard catheters is commonplace and is associated with success...

  • Paroxysmal Supraventricular Tachycardia: A Century of Progress McGuire, Mark A. // Heart, Lung & Circulation;Jun2007, Vol. 16 Issue 3, p222 

    This article reviews progress in the understanding of AV junctional reentrant tachycardia and accessory pathway-mediated tachycardia in the twentieth century and in the early part of the twenty-first century. Emphasis is placed on the contributions of John Uther and the department he founded at...

  • Nonsustained Wide QRS Tachycardia During an Exercise ECG Stress Test. MacKenzie, Ross // Journal of Insurance Medicine;2007, Vol. 39 Issue 3, p205 

    The evaluation of a nonsustained wide QRS tachycardia in a life insurance applicant's exercise test presents a special challenge to the medical director because of the unpredicatable and potentially lethal nature of these arrhythmias. Ventricular tachycardia accounts for up to 80% of wide QRS...


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics