{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,13]],"date-time":"2026-01-13T04:10:15Z","timestamp":1768277415728,"version":"3.49.0"},"reference-count":24,"publisher":"Oxford University Press (OUP)","issue":"4","license":[{"start":{"date-parts":[[2022,1,6]],"date-time":"2022-01-06T00:00:00Z","timestamp":1641427200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/academic.oup.com\/journals\/pages\/open_access\/funder_policies\/chorus\/standard_publication_model"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2022,4,5]]},"abstract":"<jats:title>Abstract<\/jats:title>\n               <jats:p>The mid-paraseptal region corresponds to the portion of the pyramidal space whose right atrial aspect is known as the triangle of Koch. The superior area of this mid-paraseptal region is also para-Hisian, and is close to the compact atrioventricular node and the His bundle. The inferior sector of the mid-paraseptal area is unrelated to the normal atrioventricular conduction pathways. It is, therefore, a safe zone in which, if necessary, to perform catheter ablation. The middle part of the mid-paraseptal zone may, however, in some patients, house components of the compact atrioventricular node. This suggests the need for adopting a prudent attitude when considering catheter ablation in this area. The inferior extensions of the atrioventricular node, which may represent the substrate for the slow atrioventricular nodal pathway, take their course through the middle, and even the inferior, sectors of the mid-paraseptal region. In this review, we contend that the middle and inferior areas of the mid-paraseptal region correspond to what, in the past, was labelled by most groups as the \u2018midseptal\u2019 zone. We describe the electrocardiographic patterns observed during pre-excitation and orthodromic reciprocating tachycardia in patients with pathways ablated in the middle or inferior sectors of the region. We discuss the modification of the ventriculo-atrial conduction times during tachycardia after the development of bundle branch block aberrancy. We conclude that the so-called \u2018intermediate septal\u2019 pathways, as described in the era of surgical ablation, were insufficiently characterized. They should not be considered the surrogate of the \u2018midseptal\u2019 pathways defined using endocardial catheter electrode mapping.<\/jats:p>","DOI":"10.1093\/europace\/euab294","type":"journal-article","created":{"date-parts":[[2021,11,9]],"date-time":"2021-11-09T04:10:23Z","timestamp":1636431023000},"page":"662-675","source":"Crossref","is-referenced-by-count":6,"title":["Miniseries 2\u2014Septal and paraseptal accessory pathways\u2014Part III: Mid-paraseptal accessory pathways\u2014revisiting bypass tracts crossing the pyramidal space"],"prefix":"10.1093","volume":"24","author":[{"given":"Jer\u00f3nimo","family":"Farr\u00e9","sequence":"first","affiliation":[{"name":"Fundaci\u00f3n Jim\u00e9nez D\u00edaz University Hospital, Institute of Biomedical Research, Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5163-9021","authenticated-orcid":false,"given":"Robert H","family":"Anderson","sequence":"additional","affiliation":[{"name":"Institute of Biosciences, Newcastle University, Newcastle upon Tyne, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jos\u00e9-Manuel","family":"Rubio","sequence":"additional","affiliation":[{"name":"Fundaci\u00f3n Jim\u00e9nez D\u00edaz University Hospital, Institute of Biomedical Research, Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Camila","family":"Garc\u00eda-Talavera","sequence":"additional","affiliation":[{"name":"Fundaci\u00f3n Jim\u00e9nez D\u00edaz University Hospital, Institute of Biomedical Research, Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Dami\u00e1n","family":"S\u00e1nchez-Quintana","sequence":"additional","affiliation":[{"name":"Department of Anatomy and Cell Biology, Universidad de Extremadura, Badajoz, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1649-8013","authenticated-orcid":false,"given":"Raghav","family":"Bansal","sequence":"additional","affiliation":[{"name":"All India Institute of Medical Sciences (AIIMS), New Delhi, India"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yash","family":"Lokhandwala","sequence":"additional","affiliation":[{"name":"Arrhythmia Associates, Mumbai, India"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jos\u00e9-Angel","family":"Cabrera","sequence":"additional","affiliation":[{"name":"Unidad de Arritmias, Departamento de Cardiolog\u00eda, Hospital Universitario Quir\u00f3n-Salud, Madrid, Spain"},{"name":"Universidad Europea, Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hein J J","family":"Wellens","sequence":"additional","affiliation":[{"name":"CARIM\u2014Cardiovascular Research Centre, Maastricht, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3249-3711","authenticated-orcid":false,"given":"Eduardo","family":"Back Sternick","sequence":"additional","affiliation":[{"name":"Arrhythmia and Electrophysiology Unit, Biocor Instituto, Nova Lima, Minas Gerais, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"286","published-online":{"date-parts":[[2022,1,6]]},"reference":[{"key":"2022040513530236700_euab294-B1","author":"Tretter","year":"2022"},{"key":"2022040513530236700_euab294-B2","author":"Anderson","year":"2022"},{"key":"2022040513530236700_euab294-B3","author":"Farr\u00e9","year":"2022"},{"key":"2022040513530236700_euab294-B4","doi-asserted-by":"crossref","first-page":"188","DOI":"10.1161\/01.CIR.97.2.188","article-title":"Posterior extensions of the human compact atrioventricular node: a neglected anatomic feature of potential clinical 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