Volume : 5
Issue : 4
Electrophysiological effects of diltiazem in chronic bifascicular block
Ajaz A Lone, Khalid Mohiud Din, Syed Manzoor Ali
Pdf Page Numbers :- 121-127
Ajaz A Lone1, Khalid Mohiud Din2 and Syed Manzoor Ali2,*
1Department of Cardiology, Sher-I-Kashmir Institute of Medical Sciences (SKIMS), Soura, Bemina, Srinagar, Jammu and Kashmir 190011, India
2Department of Cardiology, Govt Medical College Srinagar (GMC), Karan Nagar, Srinagar, Jammu and Kashmir 190010, India
*Corresping author: Dr. Syed Manzoor Ali, Assistant professor Department of Cardiology, Govt Medical College Srinagar (GMC), Karan Nagar, Srinagar, Jammu and Kashmir 190010, India. Mobile:+91 9419006441; Email: email@example.com
Received 07 July 2017; Revised 04 September 2017; Accepted 14 September 2017; Published 22 September 2017
Citation: Lone AA, Din KM, Ali SM. Electrophysiological effects of diltiazem in chronic bifascicular block. J Med Sci Res. 2017; 5(4):121-127. DOI: http://dx.doi.org/10.17727/JMSR.2017/5-23
Copyright: © 2017 Lone AA, et al. Published by KIMS Foundation and Research Center. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
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Background: Literature on diltiazem in intraventricular conduction defects is meagre. We studied effects and safety of diltiazem in chronic bifascicular block using His-bundle electrocardiography and pacing.
Methods: 23 patients with chronic bifascicular block were enrolled, all were in normal sinus rhythm. A baseline EP study,including, sinus cycle length (SCL), intra-atrial conduction time (PA), AV nodal conduction time (AH), intraventricular conduction time (HV), corrected sinus node recovery time (cSNRT), sinoatrial conduction time (SACT) and AV node wenchebach time, were assessed at baseline and repeated after diltiazem 0.25mg/kg followed by 0.0012mg/kg/min for 20 minutes.
Results: Patients with normal sinus node function (N=21), showed significant prolongation of SCL (+18%, P=.001), cSNRT (+63% P=.002), SACT (+18%, P=.001), AH (sinus), AH (paced), and wenchebach point. Patient with sinus node disease (N=2) had greater prolongation of SCL (+52%), cSNRT (695 to 4260msec) and SACT (+140%). Both patients developed left atrial rhythm. HV interval, spontaneous (59 + 11msec to 60 + 12msec P=NS) and paced (59msec + 12 to 60 +12msec P=NS), QRS and QTc intervals did not change significantly.
Conclusion: Diltiazem causes greater depression of SA and AV node in patients with sinus node dysfunction. Diltiazem did not affect the intraventricular conduction even in patients with prolonged baseline HV interval.
Keywords: diltiazem; chronic bifascicular block; sinusnode; Hispurkinje function