{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,26]],"date-time":"2026-09-26T10:42:53Z","timestamp":1790419373577,"version":"4.1.0"},"reference-count":17,"publisher":"Ovid Technologies (Wolters Kluwer Health)","issue":"17","content-domain":{"domain":["www.ahajournals.org"],"crossmark-restriction":true},"short-container-title":["Circulation"],"published-print":{"date-parts":[[2001,10,23]]},"abstract":"\n \n \n \n Background<\/jats:italic>\n <\/jats:bold>\n <\/jats:italic>\n <\/jats:bold>\n In patients with syncope and bundle branch block (BBB), syncope is suspected to be attributable to a paroxysmal atrioventricular (AV) block, but little is known of its mechanism when electrophysiological study is negative.\n <\/jats:p>\n \n \n \n \n Methods and Results<\/jats:italic>\n <\/jats:bold>\n <\/jats:italic>\n <\/jats:bold>\n We applied an implantable loop recorder in 52 patients with BBB and negative conventional workup. During a follow-up of 3 to 15 months, syncope recurred in 22 patients (42%), the event being documented in 19 patients after a median of 48 days. The most frequent finding, recorded in 17 patients, was one or more prolonged asystolic pause mainly attributable to AV block; the remaining 2 patients had normal sinus rhythm or sinus tachycardia. The onset of the bradycardic episodes was always sudden but was sometimes preceded by ventricular premature beats. The median duration of the arrhythmic event was 47 seconds. An additional 3 patients developed nonsyncopal persistent III-degree AV block, and 2 patients had presyncope attributable to AV block with asystole. No patients suffered injury attributable to syncopal relapse.\n <\/jats:p>\n \n \n \n \n Conclusions<\/jats:italic>\n <\/jats:bold>\n <\/jats:italic>\n <\/jats:bold>\n In patients with BBB and negative electrophysiological study, most syncopal recurrences have a homogeneous mechanism that is characterized by prolonged asystolic pauses, mainly attributable to sudden-onset paroxysmal AV block.\n <\/jats:p>","DOI":"10.1161\/hc4201.097837","type":"journal-article","created":{"date-parts":[[2007,9,28]],"date-time":"2007-09-28T14:31:09Z","timestamp":1190989869000},"page":"2045-2050","update-policy":"https:\/\/doi.org\/10.1161\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":268,"title":["Mechanism of Syncope in Patients With Bundle Branch Block and Negative Electrophysiological Test"],"prefix":"10.1161","volume":"104","author":[{"given":"Michele","family":"Brignole","sequence":"first","affiliation":[{"name":"From the Departments of Cardiology, Ospedali Riuniti (M.B., P.D.), Lavagna, Italy; Ospedale S. Maria Nuova (C.M., N.B.), Reggio Emilia, Italy; Hospital Vall d\u2019Hebron (A.M.), Barcelona, Spain; Hospital Clinico Universitario (R.G.-C.), Valencia, Spain; Hospital Clinico (L.M.), Barcelona, Spain; Hospital Virgen de las Nives (M.A.), Granada, Spain; Hospital Virgen del Rocio (F.E.), Sevilla, Spain; and Hospital Xeral de Vigo (J.B.), Vigo, Spain."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Carlo","family":"Menozzi","sequence":"additional","affiliation":[{"name":"From the Departments of Cardiology, Ospedali Riuniti (M.B., P.D.), Lavagna, Italy; Ospedale S. Maria Nuova (C.M., N.B.), Reggio Emilia, Italy; Hospital Vall d\u2019Hebron (A.M.), Barcelona, Spain; Hospital Clinico Universitario (R.G.-C.), Valencia, Spain; Hospital Clinico (L.M.), Barcelona, Spain; Hospital Virgen de las Nives (M.A.), Granada, Spain; Hospital Virgen del Rocio (F.E.), Sevilla, Spain; and Hospital Xeral de Vigo (J.B.), Vigo, Spain."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Angel","family":"Moya","sequence":"additional","affiliation":[{"name":"From the Departments of Cardiology, Ospedali Riuniti (M.B., P.D.), Lavagna, Italy; Ospedale S. Maria Nuova (C.M., N.B.), Reggio Emilia, Italy; Hospital Vall d\u2019Hebron (A.M.), Barcelona, Spain; Hospital Clinico Universitario (R.G.-C.), Valencia, Spain; Hospital Clinico (L.M.), Barcelona, Spain; Hospital Virgen de las Nives (M.A.), Granada, Spain; Hospital Virgen del Rocio (F.E.), Sevilla, Spain; and Hospital Xeral de Vigo (J.B.), Vigo, Spain."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Roberto","family":"Garcia-Civera","sequence":"additional","affiliation":[{"name":"From the Departments of Cardiology, Ospedali Riuniti (M.B., P.D.), Lavagna, Italy; Ospedale S. Maria Nuova (C.M., N.B.), Reggio Emilia, Italy; Hospital Vall d\u2019Hebron (A.M.), Barcelona, Spain; Hospital Clinico Universitario (R.G.-C.), Valencia, Spain; Hospital Clinico (L.M.), Barcelona, Spain; Hospital Virgen de las Nives (M.A.), Granada, Spain; Hospital Virgen del Rocio (F.E.), Sevilla, Spain; and Hospital Xeral de Vigo (J.B.), Vigo, Spain."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Luis","family":"Mont","sequence":"additional","affiliation":[{"name":"From the Departments of Cardiology, Ospedali Riuniti (M.B., P.D.), Lavagna, Italy; Ospedale S. Maria Nuova (C.M., N.B.), Reggio Emilia, Italy; Hospital Vall d\u2019Hebron (A.M.), Barcelona, Spain; Hospital Clinico Universitario (R.G.-C.), Valencia, Spain; Hospital Clinico (L.M.), Barcelona, Spain; Hospital Virgen de las Nives (M.A.), Granada, Spain; Hospital Virgen del Rocio (F.E.), Sevilla, Spain; and Hospital Xeral de Vigo (J.B.), Vigo, Spain."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Miguel","family":"Alvarez","sequence":"additional","affiliation":[{"name":"From the Departments of Cardiology, Ospedali Riuniti (M.B., P.D.), Lavagna, Italy; Ospedale S. Maria Nuova (C.M., N.B.), Reggio Emilia, Italy; Hospital Vall d\u2019Hebron (A.M.), Barcelona, Spain; Hospital Clinico Universitario (R.G.-C.), Valencia, Spain; Hospital Clinico (L.M.), Barcelona, Spain; Hospital Virgen de las Nives (M.A.), Granada, Spain; Hospital Virgen del Rocio (F.E.), Sevilla, Spain; and Hospital Xeral de Vigo (J.B.), Vigo, Spain."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Francisco","family":"Errazquin","sequence":"additional","affiliation":[{"name":"From the Departments of Cardiology, Ospedali Riuniti (M.B., P.D.), Lavagna, Italy; Ospedale S. Maria Nuova (C.M., N.B.), Reggio Emilia, Italy; Hospital Vall d\u2019Hebron (A.M.), Barcelona, Spain; Hospital Clinico Universitario (R.G.-C.), Valencia, Spain; Hospital Clinico (L.M.), Barcelona, Spain; Hospital Virgen de las Nives (M.A.), Granada, Spain; Hospital Virgen del Rocio (F.E.), Sevilla, Spain; and Hospital Xeral de Vigo (J.B.), Vigo, Spain."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Julio","family":"Beiras","sequence":"additional","affiliation":[{"name":"From the Departments of Cardiology, Ospedali Riuniti (M.B., P.D.), Lavagna, Italy; Ospedale S. Maria Nuova (C.M., N.B.), Reggio Emilia, Italy; Hospital Vall d\u2019Hebron (A.M.), Barcelona, Spain; Hospital Clinico Universitario (R.G.-C.), Valencia, Spain; Hospital Clinico (L.M.), Barcelona, Spain; Hospital Virgen de las Nives (M.A.), Granada, Spain; Hospital Virgen del Rocio (F.E.), Sevilla, Spain; and Hospital Xeral de Vigo (J.B.), Vigo, Spain."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nicola","family":"Bottoni","sequence":"additional","affiliation":[{"name":"From the Departments of Cardiology, Ospedali Riuniti (M.B., P.D.), Lavagna, Italy; Ospedale S. Maria Nuova (C.M., N.B.), Reggio Emilia, Italy; Hospital Vall d\u2019Hebron (A.M.), Barcelona, Spain; Hospital Clinico Universitario (R.G.-C.), Valencia, Spain; Hospital Clinico (L.M.), Barcelona, Spain; Hospital Virgen de las Nives (M.A.), Granada, Spain; Hospital Virgen del Rocio (F.E.), Sevilla, Spain; and Hospital Xeral de Vigo (J.B.), Vigo, Spain."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Paolo","family":"Donateo","sequence":"additional","affiliation":[{"name":"From the Departments of Cardiology, Ospedali Riuniti (M.B., P.D.), Lavagna, Italy; Ospedale S. Maria Nuova (C.M., N.B.), Reggio Emilia, Italy; Hospital Vall d\u2019Hebron (A.M.), Barcelona, Spain; Hospital Clinico Universitario (R.G.-C.), Valencia, Spain; Hospital Clinico (L.M.), Barcelona, Spain; Hospital Virgen de las Nives (M.A.), Granada, Spain; Hospital Virgen del Rocio (F.E.), Sevilla, Spain; and Hospital Xeral de Vigo (J.B.), Vigo, Spain."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"name":"on behalf of the International Study on Syncope of Uncertain Etiology (ISSUE) Investigators","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"276","reference":[{"key":"e_1_3_2_1_2","first-page":"768","volume":"14","year":"1984","unstructured":"Gronda M, Magnani A, Occhetta E, et al. Electrophysiologic study of atrio-ventricular block and ventricular conduction defects. G Ital Cardiol. 1984; 14: 768\u2013773.","journal-title":"G Ital Cardiol"},{"key":"e_1_3_2_2_2","doi-asserted-by":"publisher","DOI":"10.1016\/S0002-9149(99)00096-X"},{"key":"e_1_3_2_3_2","first-page":"409","volume":"24","year":"1994","unstructured":"Gaggioli G, Bottoni N, Brignole M, et al. Progression to second- or third-degree atrioventricular block in patients electrostimulated for bundle branch block: a long-term study. G Ital Cardiol. 1994; 24: 409\u2013416.","journal-title":"G Ital Cardiol"},{"key":"e_1_3_2_4_2","doi-asserted-by":"publisher","DOI":"10.1016\/0002-9149(87)91098-8"},{"key":"e_1_3_2_5_2","doi-asserted-by":"publisher","DOI":"10.1016\/0735-1097(95)00354-1"},{"key":"e_1_3_2_6_2","first-page":"406","volume":"26","year":"1999","unstructured":"Krahn AD, Klein GJ, Yee R, Takle-Newhouse T, Norris C. Use of an extended monitoring strategy in patients with problematic syncope: Reveal Investigators. Circulation. 1999; 26: 99: 406\u2013410.","journal-title":"Circulation"},{"key":"e_1_3_2_7_2","doi-asserted-by":"publisher","DOI":"10.1161\/circ.104.11.1261"},{"key":"e_1_3_2_8_2","doi-asserted-by":"publisher","DOI":"10.1161\/circ.95.4.951"},{"key":"e_1_3_2_9_2","doi-asserted-by":"publisher","DOI":"10.1053\/eupc.1998.0015"},{"key":"e_1_3_2_10_2","doi-asserted-by":"publisher","DOI":"10.1056\/NEJM198207153070301"},{"key":"e_1_3_2_11_2","doi-asserted-by":"publisher","DOI":"10.1016\/0002-9149(82)90469-6"},{"key":"e_1_3_2_12_2","doi-asserted-by":"publisher","DOI":"10.1161\/circ.60.7.498473"},{"key":"e_1_3_2_13_2","first-page":"679","volume":"19","year":"1996","unstructured":"Petrac D, Radic B, Birtic K, Gjurovic J. Prospective evaluation of infrahisal second-degree AV block induced by atrial pacing in the presence of chronic bundle branch block and syncope. PACE Pacing Clin Electrophysiol. 1996; 19; 679\u2013687.","journal-title":"PACE Pacing Clin Electrophysiol"},{"key":"e_1_3_2_14_2","doi-asserted-by":"publisher","DOI":"10.1016\/0002-9149(87)91098-8"},{"key":"e_1_3_2_15_2","unstructured":"Dini P Iaolongo D Adinolfi E et al. Prognostic value of His-ventricular conduction after ajmaline administration.In: Masoni A Alboni P eds. Cardiac Electrophysiology Today. London: Academic Press; 1982: 515\u2013522."},{"key":"e_1_3_2_16_2","doi-asserted-by":"crossref","unstructured":"Kaul U Dev V Narula J Malhotra A Talwar K Bhatia M. Evaluation of patients with bundle branch block and \u201cunexplained\u201d syncope: a study based on comprehensive electrophysiologic testing and ajmaline stress.PACE. 1988; 11: 289\u2013297.","DOI":"10.1111\/j.1540-8159.1988.tb05006.x"},{"key":"e_1_3_2_17_2","unstructured":"Rardon D Miles W Mitrani R et al. Atrioventricular block and dissociation.In: Zipes D Jalife J eds. Cardiac Electrophysiology: From Cell to Bedside. Philadelphia Pa: Saunders; 1995: 935\u2013954."}],"container-title":["Circulation"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.ahajournals.org\/doi\/full\/10.1161\/hc4201.097837","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2024,5,13]],"date-time":"2024-05-13T21:46:05Z","timestamp":1715636765000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.ahajournals.org\/doi\/10.1161\/hc4201.097837"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2001,10,23]]},"references-count":17,"journal-issue":{"issue":"17","published-print":{"date-parts":[[2001,10,23]]}},"alternative-id":["10.1161\/hc4201.097837"],"URL":"https:\/\/doi.org\/10.1161\/hc4201.097837","relation":{},"ISSN":["0009-7322","1524-4539"],"issn-type":[{"value":"0009-7322","type":"print"},{"value":"1524-4539","type":"electronic"}],"subject":[],"published":{"date-parts":[[2001,10,23]]},"assertion":[{"value":"2001-10-23","order":2,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}]}}