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: Cumulative effects of heart beat on ventricular premature contractions suggesting possible involvement of triggered activity. Author: Koumatsu K, Ito M, Fujino T, Saikawa T, Arita M. Journal: Jpn Circ J; 1993 Jun; 57(6):503-11. PubMed ID: 8340997. Abstract: We analyzed 24 h ECG recordings of 29 patients with frequent (> 2000/day) ventricular premature contractions (VPCs) to evaluate: 1) the relationship between VPC frequency and heart rate (HR); 2) the relationship between the coupling interval (CI) of VPCs and HR; 3) the time course of changes in VPC frequency following an abrupt and sustained increase in HR; and 4) the effect of oral diltiazem (90 or 180 mg/day for 4 weeks) on VPCs. Based on the patterns of relationship between VPC frequency and HR, patients were divided into 2 groups: 1) 17 patients with a positive correlation, the P group (a linear increase in VPCs with increasing HRs); and 2) 12 patients with a non-positive correlation, the NP group. The NP group showed either a linear decrease in VPCs with increased HRs (4 patients) or an increase in VPCs at low HRs and a decrease at high HRs (8 patients). In all cases, an increased HR was associated with a shortening of CI. In the P group, changes in VPCs after an abrupt increase in HR showed 2 types: 1) delayed-ascent type, in which VPCs increased as the duration of HR increase was prolonged (cumulative effects of heart beat) (7 patients); and non-delayed-ascent type (10 patients). Diltiazem reduced VPCs > or = 75% in all of the 7 delayed-ascent-type patients, compared with 3 of the 10 non-delayed-ascent-type patients (p < 0.05) and none of the 12 patients in the NP group (p < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)[Abstract] [Full Text] [Related] [New Search]