{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,14]],"date-time":"2026-07-14T07:18:01Z","timestamp":1784013481063,"version":"3.55.0"},"reference-count":40,"publisher":"Wiley","issue":"2","license":[{"start":{"date-parts":[[2007,10,25]],"date-time":"2007-10-25T00:00:00Z","timestamp":1193270400000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/onlinelibrary.wiley.com\/termsAndConditions#vor"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Cardiovasc electrophysiol"],"published-print":{"date-parts":[[2008,2]]},"abstract":"<jats:p> <jats:italic>Background:<\/jats:italic> RV apical pacing (RVP) may be deleterious, possibly by simulating LBBB, i.e., prolonging QRS duration (QRSd) and LV activation (LVAT). However, determinants of electrical delays are unknown.<\/jats:p><jats:p> <jats:italic>Hypothesis:<\/jats:italic> LV dysfunction (LVEF \u2264 40%, HF) and pre\u2010existing conduction system abnormalities may modulate RVP's effects, compared to LBBB.<\/jats:p><jats:p> <jats:italic>Methods:<\/jats:italic> RVP\u2010induced QRSd and LVAT were compared in normal LV to HF, with normal QRS (&lt;120 ms), RBBB, or LBBB. LVAT was estimated by interval from QRS onset to basal inferolateral LV depolarization.<\/jats:p><jats:p> <jats:italic>Results:<\/jats:italic> During LBBB and RVP, LVAT\/QRSd was \u226585%, i.e., LVAT indicated terminal LV depolarization. In normal LV, LVAT during intrinsic conduction (55 \u00b1 18 ms) was delayed by RVP (129 \u00b1 20 ms, n = 58, P &lt; 0.001). RVP's effects were similar to LBBB (P = NS) and unaffected by baseline conduction disease. In HF overall, RVP\u2010induced delays (QRSd 209 \u00b1 27, LVAT 186 \u00b1 26 ms, n = 102) were greater than RVP in normal LV (P &lt; 0.001). When baseline conduction system disease was present, RVP's effects were exaggerated (RVP wide QRS [&gt;120 ms]: QRSd 216 \u00b1 27, LVAT 191 \u00b1 20 ms, [n = 72] vs RVP normal QRS: QRSd 193 \u00b1 24, LVAT 169 \u00b1 24 ms, n = 31, P &lt; 0.001). In patients with LBBB (n = 41), delays during intrinsic conduction (QRSd 163 \u00b1 29, LVAT 137 \u00b1 33 ms, n = 41) were enhanced by RVP (QRSd 218 \u00b1 28, LVAT 191 \u00b1 22 ms, P &lt; 0.001). RVP's effects were similar in patients with LBBB and RBBB (P = NS).<\/jats:p><jats:p> <jats:italic>Conclusion:<\/jats:italic> RVP simulated LBBB in normal LV. In HF, RVP induced greater conduction delays than LBBB, enhanced by accompanying conduction disease. These variations may contribute to RVP's mixed clinical effects.<\/jats:p>","DOI":"10.1111\/j.1540-8167.2007.00995.x","type":"journal-article","created":{"date-parts":[[2007,10,27]],"date-time":"2007-10-27T22:00:41Z","timestamp":1193522441000},"page":"114-122","source":"Crossref","is-referenced-by-count":69,"title":["Left Ventricular Conduction Delays Induced by Right Ventricular Apical Pacing: Effect of Left Ventricular Dysfunction and Bundle Branch Block"],"prefix":"10.1111","volume":"19","author":[{"given":"NIRAJ","family":"VARMA","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2007,10,25]]},"reference":[{"key":"e_1_2_6_2_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.hrthm.2005.06.004"},{"key":"e_1_2_6_3_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.hrthm.2006.08.006"},{"key":"e_1_2_6_4_2","doi-asserted-by":"publisher","DOI":"10.1001\/jama.288.24.3115"},{"key":"e_1_2_6_5_2","doi-asserted-by":"publisher","DOI":"10.1016\/S0002-9149(02)02396-2"},{"key":"e_1_2_6_6_2","doi-asserted-by":"publisher","DOI":"10.1046\/j.1540-8167.2005.50038.x"},{"key":"e_1_2_6_7_2","doi-asserted-by":"publisher","DOI":"10.1161\/01.CIR.0000072769.17295.B1"},{"key":"e_1_2_6_8_2","doi-asserted-by":"publisher","DOI":"10.1016\/0002-8703(52)90099-9"},{"key":"e_1_2_6_9_2","doi-asserted-by":"publisher","DOI":"10.1161\/01.CIR.61.4.696"},{"key":"e_1_2_6_10_2","first-page":"29","volume-title":"The conduction system of the heart","author":"Gelband H","year":"1976"},{"key":"e_1_2_6_11_2","first-page":"107","volume-title":"Braunwald's heart disease","author":"Mirvis D, Goldberger A","year":"2005"},{"key":"e_1_2_6_12_2","doi-asserted-by":"publisher","DOI":"10.1111\/j.1540-8159.2007.00719.x"},{"key":"e_1_2_6_13_2","doi-asserted-by":"publisher","DOI":"10.1046\/j.1540-8167.2003.02421.x"},{"key":"e_1_2_6_14_2","doi-asserted-by":"crossref","first-page":"194","DOI":"10.1016\/S0735-1097(01)01747-8","article-title":"Retiming the failing heart: Principles and current clinical status of cardiac resynchronization","volume":"39","author":"Leclerq C KD","year":"1999","journal-title":"J Am Coll Cardiol"},{"key":"e_1_2_6_15_2","doi-asserted-by":"publisher","DOI":"10.1067\/mhj.2002.121264"},{"key":"e_1_2_6_16_2","doi-asserted-by":"publisher","DOI":"10.1046\/j.1540-8167.2005.40568.x"},{"key":"e_1_2_6_17_2","doi-asserted-by":"publisher","DOI":"10.1056\/NEJMoa050496"},{"key":"e_1_2_6_18_2","doi-asserted-by":"publisher","DOI":"10.1161\/01.RES.0000144125.61927.1c"},{"key":"e_1_2_6_19_2","doi-asserted-by":"publisher","DOI":"10.1161\/hc0402.102975"},{"key":"e_1_2_6_20_2","doi-asserted-by":"publisher","DOI":"10.1161\/01.CIR.41.6.899"},{"key":"e_1_2_6_21_2","doi-asserted-by":"publisher","DOI":"10.1016\/S0735-1097(86)80140-1"},{"key":"e_1_2_6_22_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.hrthm.2005.11.025"},{"key":"e_1_2_6_23_2","first-page":"377","volume-title":"The conduction system of the heart","author":"Dam RV","year":"1976"},{"key":"e_1_2_6_24_2","doi-asserted-by":"crossref","unstructured":"PrinzenFW SpinelliJC AuricchioA:Basic physiology and hemodynamics of cardiac pacing clinical cardiac pacing defibrillation and resynchronization therapy. Philadelphia PA :Saunders Elsevier 2007 p.295.","DOI":"10.1016\/B978-1-4160-2536-8.50014-5"},{"key":"e_1_2_6_25_2","doi-asserted-by":"publisher","DOI":"10.1016\/S0002-9149(03)00886-5"},{"key":"e_1_2_6_26_2","doi-asserted-by":"publisher","DOI":"10.1016\/S0002-9149(01)01619-8"},{"key":"e_1_2_6_27_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.cardfail.2005.03.008"},{"key":"e_1_2_6_28_2","doi-asserted-by":"publisher","DOI":"10.1016\/S1053-2498(02)00431-X"},{"key":"e_1_2_6_29_2","doi-asserted-by":"publisher","DOI":"10.1161\/01.CIR.0000147187.78162.AC"},{"key":"e_1_2_6_30_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.jacc.2005.09.029"},{"key":"e_1_2_6_31_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.cardiores.2005.03.008"},{"key":"e_1_2_6_32_2","doi-asserted-by":"publisher","DOI":"10.1111\/j.1540-8167.2006.00741.x"},{"key":"e_1_2_6_33_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.hrthm.2004.12.012"},{"key":"e_1_2_6_34_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.jacc.2006.05.071"},{"key":"e_1_2_6_35_2","doi-asserted-by":"publisher","DOI":"10.1161\/01.CIR.0000070930.33499.9F"},{"key":"e_1_2_6_36_2","doi-asserted-by":"publisher","DOI":"10.1016\/S0735-1097(02)01779-5"},{"key":"e_1_2_6_37_2","doi-asserted-by":"publisher","DOI":"10.1111\/j.1540-8167.2005.50062.x"},{"key":"e_1_2_6_38_2","doi-asserted-by":"publisher","DOI":"10.1111\/j.1540-8167.2007.00788.x"},{"key":"e_1_2_6_39_2","first-page":"H428","article-title":"Influence of pacing site on canine left ventricular contraction","volume":"251","author":"Burkhoff D","year":"1986","journal-title":"Am J Physiol"},{"key":"e_1_2_6_40_2","doi-asserted-by":"publisher","DOI":"10.1016\/S0735-1097(98)00562-2"},{"key":"e_1_2_6_41_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.jacc.2006.05.072"}],"container-title":["Journal of Cardiovascular Electrophysiology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/api.wiley.com\/onlinelibrary\/tdm\/v1\/articles\/10.1111%2Fj.1540-8167.2007.00995.x","content-type":"unspecified","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1111\/j.1540-8167.2007.00995.x","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2023,10,11]],"date-time":"2023-10-11T04:59:41Z","timestamp":1697000381000},"score":1,"resource":{"primary":{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/10.1111\/j.1540-8167.2007.00995.x"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2007,10,25]]},"references-count":40,"journal-issue":{"issue":"2","published-print":{"date-parts":[[2008,2]]}},"alternative-id":["10.1111\/j.1540-8167.2007.00995.x"],"URL":"https:\/\/doi.org\/10.1111\/j.1540-8167.2007.00995.x","archive":["Portico"],"relation":{},"ISSN":["1045-3873","1540-8167"],"issn-type":[{"value":"1045-3873","type":"print"},{"value":"1540-8167","type":"electronic"}],"subject":[],"published":{"date-parts":[[2007,10,25]]}}}