{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,9,4]],"date-time":"2025-09-04T14:20:49Z","timestamp":1756995649734},"reference-count":27,"publisher":"Wiley","issue":"9","license":[{"start":{"date-parts":[[2009,2,4]],"date-time":"2009-02-04T00:00:00Z","timestamp":1233705600000},"content-version":"vor","delay-in-days":8922,"URL":"http:\/\/onlinelibrary.wiley.com\/termsAndConditions#vor"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Clinical Cardiology"],"published-print":{"date-parts":[[1984,9]]},"abstract":"<jats:title>Abstract<\/jats:title><jats:p>We determined the effects of single intravenous (10 mg) and oral (80, 160 mg) doses of verapamil in 8 digitalized patients with chronic atrial fibrillation. The time course of drug effect was analyzed with computer assistance by considering several measures in atrial fibrillation, including average R\u2010R interval (ARR), shortest R\u2010R interval (SRR), longest R\u2010R interval (LRR), and variability of R\u2010R intervals. Peak plasma concentrations of verapamil were observed immediately after intravenous verapamil (mean elimination half\u2010life of 3.3 h) and 1 hour after oral verapamil (mean elimination half\u2010life 3.4 h, 80 mg; 3.1 h, 160 mg). In contrast to previous studies, we observed the maximum bradycardie effect of intravenous verapamil to occur at one\u2010half to 1 h, and this effect lasted for 2\u20134 h. Following oral verapamil the peak effect occurred at 3\u20134 h and lasted for 5\u20138 h. Analysise time course of changes in ARR, SRR, LRR, and variability of R\u2010R revealed two distinct \u201cpatterns\u201d of ventricular response. In one group (4 of 8 patients), verapamil caused an increase in SRR but a decrease in LRR. R\u2010R intervals \u201cregularized\u201d in this group. In the remaining patients, verapamil increased the SRR but did not change or increase the LRR. This enhanced the observed increase in ARR intervals. We postulate that the decrease in LRR intervals after verapamil is due to reflex adrenergic discharge as a result of the vasodilator effect of the drug while the increase in SRR is a direct effect. These two opposing effects result in regularization of R\u2010R intervals in many patients. Patients demonstrating an increase in LRR intervals after verapamil may not get reflex adrenergic discharge or may be incapable of responding to the latter due to conduction disease; these patients may experience brady cardie complications after verapamil.<\/jats:p>","DOI":"10.1002\/clc.4960070903","type":"journal-article","created":{"date-parts":[[2009,2,5]],"date-time":"2009-02-05T01:53:42Z","timestamp":1233798822000},"page":"474-483","source":"Crossref","is-referenced-by-count":6,"title":["Verapamil in chronic atrial fibrillation: Variable patterns of response in ventricular rate"],"prefix":"10.1002","volume":"7","author":[{"given":"G. J.","family":"Klein","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Y.","family":"Twum\u2010Barima","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"S.","family":"Gulamhusein","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"S. G.","family":"Carruthers","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"A. P.","family":"Donner","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"311","published-online":{"date-parts":[[2009,2,4]]},"reference":[{"key":"e_1_2_1_2_1","first-page":"cl","article-title":"Ca and Na selectivity of the active membrane of rabbit AV nodal cells","volume":"36","author":"Akiyama T","year":"1979","journal-title":"Am J Physiol"},{"key":"e_1_2_1_3_1","doi-asserted-by":"publisher","DOI":"10.1002\/cpt1979265578"},{"key":"e_1_2_1_4_1","doi-asserted-by":"publisher","DOI":"10.1136\/bmj.2.5806.169-b"},{"key":"e_1_2_1_5_1","doi-asserted-by":"publisher","DOI":"10.1016\/0002-8703(78)90009-1"},{"key":"e_1_2_1_6_1","doi-asserted-by":"publisher","DOI":"10.1002\/cpt1979266710"},{"key":"e_1_2_1_7_1","doi-asserted-by":"publisher","DOI":"10.1097\/00005344-198101000-00003"},{"key":"e_1_2_1_8_1","doi-asserted-by":"publisher","DOI":"10.1161\/01.CIR.59.2.313"},{"key":"e_1_2_1_9_1","first-page":"49","article-title":"Pharmacodynamic comparison of oral and intravenous verapamil in atrial fibrillation","volume":"3","author":"Follath F","year":"1980","journal-title":"Clin Invest Med"},{"key":"e_1_2_1_10_1","first-page":"1681","article-title":"Gas chromatographic determination of verapamil in plasma and urine","volume":"29","author":"Hege HG","year":"1979","journal-title":"Arzneim Forsch"},{"key":"e_1_2_1_11_1","doi-asserted-by":"publisher","DOI":"10.1016\/0002-8703(75)90431-7"},{"key":"e_1_2_1_12_1","doi-asserted-by":"publisher","DOI":"10.1136\/hrt.35.7.734"},{"key":"e_1_2_1_13_1","doi-asserted-by":"publisher","DOI":"10.1111\/j.1365-2125.1981.tb01233.x"},{"key":"e_1_2_1_14_1","doi-asserted-by":"publisher","DOI":"10.1111\/j.0954-6820.1979.tb06093.x"},{"key":"e_1_2_1_15_1","doi-asserted-by":"publisher","DOI":"10.1016\/0002-9149(82)90285-5"},{"key":"e_1_2_1_16_1","doi-asserted-by":"crossref","first-page":"747","DOI":"10.1001\/archinte.1979.03630440017009","article-title":"Beneficial effects of verapamil in chronic atrial fibrillation","volume":"139","author":"Klein HO","year":"1979","journal-title":"Arch Intern Med"},{"key":"e_1_2_1_17_1","first-page":"37","article-title":"Pharmcokinetics of verapamil in man","volume":"24","author":"Koike Y","year":"1979","journal-title":"Res Commun Chem Pathol Pharmacol"},{"key":"e_1_2_1_18_1","doi-asserted-by":"publisher","DOI":"10.1136\/pgmj.50.583.270"},{"key":"e_1_2_1_19_1","doi-asserted-by":"publisher","DOI":"10.1016\/0002-8703(80)90215-X"},{"key":"e_1_2_1_20_1","doi-asserted-by":"publisher","DOI":"10.1093\/cvr\/5.4.419"},{"key":"e_1_2_1_21_1","doi-asserted-by":"publisher","DOI":"10.1136\/bmj.1.5801.660"},{"key":"e_1_2_1_22_1","first-page":"1452","article-title":"The phar\u2010macodynamics of orally taken verapamil and verapamil retard as judged by their negative dromotropic effects","volume":"25","author":"Schlepper M","year":"1975","journal-title":"Arzneim Forsch"},{"key":"e_1_2_1_23_1","doi-asserted-by":"publisher","DOI":"10.1016\/S0002-8703(77)80128-2"},{"key":"e_1_2_1_24_1","doi-asserted-by":"publisher","DOI":"10.1016\/0010-4809(77)90015-5"},{"key":"e_1_2_1_25_1","doi-asserted-by":"publisher","DOI":"10.1016\/0002-9149(79)90283-2"},{"key":"e_1_2_1_26_1","first-page":"H308","article-title":"Autonomic control of pacemaker activity in the atrioventricular junction of the dog","volume":"4","author":"Wallick DW","year":"1978","journal-title":"Am J Physiol"},{"key":"e_1_2_1_27_1","doi-asserted-by":"publisher","DOI":"10.7326\/0003-4819-94-1-1"},{"key":"e_1_2_1_28_1","doi-asserted-by":"publisher","DOI":"10.1161\/01.RES.35.3.413"}],"container-title":["Clinical Cardiology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/api.wiley.com\/onlinelibrary\/tdm\/v1\/articles\/10.1002%2Fclc.4960070903","content-type":"unspecified","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/clc.4960070903","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2023,10,19]],"date-time":"2023-10-19T20:07:54Z","timestamp":1697746074000},"score":1,"resource":{"primary":{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/10.1002\/clc.4960070903"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1984,9]]},"references-count":27,"journal-issue":{"issue":"9","published-print":{"date-parts":[[1984,9]]}},"alternative-id":["10.1002\/clc.4960070903"],"URL":"https:\/\/doi.org\/10.1002\/clc.4960070903","archive":["Portico"],"relation":{},"ISSN":["0160-9289","1932-8737"],"issn-type":[{"value":"0160-9289","type":"print"},{"value":"1932-8737","type":"electronic"}],"subject":[],"published":{"date-parts":[[1984,9]]}}}