These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Electrophysiologic variables characterizing the induction of ventricular tachycardia versus ventricular fibrillation after myocardial infarction: relation between ventricular late potentials and coupling intervals for the induction of sustained ventricular tachyarrhythmias.
    Author: Martinez-Rubio A, Shenasa M, Borggrefe M, Chen X, Benning F, Breithardt G.
    Journal: J Am Coll Cardiol; 1993 Jun; 21(7):1624-31. PubMed ID: 8496529.
    Abstract:
    OBJECTIVES: The aim of this study was to analyze the relations between the presence of ventricular conduction delay and the necessary coupling intervals for the induction of sustained ventricular tachyarrhythmias. METHODS: The electrophysiologic and signal-averaged electrocardiographic (ECG) data from 83 patients with previous myocardial infarction and inducible sustained monomorphic ventricular tachycardia (n = 71) and ventricular fibrillation (n = 12) were analyzed. RESULTS: The sum of the coupling intervals needed for inducing ventricular tachycardia and ventricular fibrillation was 485 +/- 59 ms and 387 +/- 36 ms, respectively (p < 0.001). The mean difference between the effective refractory period and the second coupling interval for the induction of ventricular tachycardia and ventricular fibrillation was -3 +/- 40 ms and 24 +/- 29 ms, respectively (p < 0.02). QRS duration and duration of terminal low amplitude signals of the QRS complex (p < 0.004) were longer in patients with inducible ventricular tachycardia than in patients with inducible ventricular fibrillation. The root mean square of the voltage during the last 40 ms of QRS complex was lower in patients with inducible ventricular tachycardia than in patients with inducible ventricular fibrillation (p < 0.007). Patients with inducible ventricular tachycardia presented with a greater prevalence of ventricular late potentials than that of patients with inducible ventricular fibrillation (p < 0.007). For arrhythmia induction, significantly shorter coupling intervals were necessary in patients without than in patients with ventricular late potentials. A positive correlation was found between the cycle length of the induced ventricular tachycardia and the filtered QRS duration as well as with the sum of the coupling intervals. CONCLUSIONS: Induction of ventricular fibrillation requires shorter coupling intervals than does induction of ventricular tachycardia. The presence of ventricular conduction delay seems to be a marker of facilitated induction of sustained monomorphic ventricular tachycardia rather than of ventricular fibrillation. The coupling intervals required to induce ventricular tachycardia or fibrillation are longer in patients with than in those without an abnormal signal-averaged ECG.
    [Abstract] [Full Text] [Related] [New Search]