{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,12]],"date-time":"2026-01-12T11:12:02Z","timestamp":1768216322784,"version":"3.49.0"},"reference-count":8,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,1,12]],"date-time":"2026-01-12T00:00:00Z","timestamp":1768176000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Pediatr."],"abstract":"<jats:p>The initial electrocardiogram (ECG) of a 5-month-old infant with complex congenital heart disease (pulmonary valvular stenosis, ventricular septal defects, and patent ductus arteriosus) revealed a regular wide QRS tachycardia at 169\u2005bpm, initially suggestive of ventricular tachycardia (VT) or supraventricular tachycardia (SVT) with aberrant conduction. However, a subsequent ECG obtained during spontaneous heart rate deceleration to 143\u2005bpm showed narrow QRS complexes with discernible sinus P waves and a markedly prolonged PR interval (300\u2005ms). These findings establish the diagnosis of sinus rhythm with biatrial enlargement and first-degree atrioventricular (AV) block. Comparative analysis of these ECGs revealed that the initial tracing did not represent a true wide QRS complex but rather a \u201cpseudo-wide QRS complex\u201d tachycardia. This phenomenon occurs when profound PR prolongation results in concealed sinus P waves overlapping the terminal portion of the preceding QRS complex, thereby mimicking a wide QRS complex. The significant PR interval prolongation, reflecting first-degree AV block, is likely attributable to underlying anatomical abnormalities leading to atrial enlargement and consequent impaired AV nodal conduction. This case report highlights the critical importance of meticulously identifying concealed sinus P waves within wide QRS rhythms to prevent misdiagnosis and inappropriate interventions.<\/jats:p>","DOI":"10.3389\/fped.2025.1643670","type":"journal-article","created":{"date-parts":[[2026,1,12]],"date-time":"2026-01-12T08:10:57Z","timestamp":1768205457000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Case Report: Pseudo-wide QRS complex tachycardia in an infant with complex congenital heart disease"],"prefix":"10.3389","volume":"13","author":[{"given":"Hualian","family":"Li","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jingjing","family":"Cong","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tingting","family":"Yu","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zhongmin","family":"You","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jie","family":"Wen","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Heng","family":"Li","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1965","published-online":{"date-parts":[[2026,1,12]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"e102","DOI":"10.1016\/j.hrthm.2014.05.009","article-title":"PACES\/HRS expert consensus statement on the recognition and management of arrhythmias in adult congenital heart disease","volume":"11","author":"Khairy","year":"2014","journal-title":"Heart Rhythm"},{"key":"B2","doi-asserted-by":"publisher","first-page":"e506","DOI":"10.1161\/CIR.0000000000000311","article-title":"2015 ACC\/AHA\/HRS guideline for the management of adult patients with supraventricular tachycardia: a report of the American College of Cardiology\/American Heart Association task force on clinical practice guidelines and the Heart Rhythm Society","volume":"133","author":"Page","year":"2016","journal-title":"Circulation"},{"key":"B3","doi-asserted-by":"publisher","first-page":"e55","DOI":"10.1016\/j.hrthm.2014.05.010","article-title":"PACES\/HRS expert consensus statement on the evaluation and management of ventricular arrhythmias in the child with a structurally normal heart","volume":"11","author":"Crosson","year":"2014","journal-title":"Heart Rhythm"},{"key":"B4","doi-asserted-by":"publisher","first-page":"831","DOI":"10.1016\/j.jacep.2022.03.017","article-title":"Simplified integrated clinical and electrocardiographic algorithm for differentiation of wide QRS complex tachycardia","volume":"8","author":"Moccetti","year":"2022","journal-title":"JACC Clin Electrophysiol"},{"key":"B5","doi-asserted-by":"publisher","first-page":"1870","DOI":"10.1161\/CIRCULATIONAHA.117.027647","article-title":"Wide QRS complex tachycardia","volume":"135","author":"Wang","year":"2017","journal-title":"Circulation"},{"key":"B6","doi-asserted-by":"publisher","first-page":"2278","DOI":"10.1161\/CIRCULATIONAHA.120.051205","article-title":"Wide QRS complex tachycardia in a young pregnant woman","volume":"142","author":"Rajendran","year":"2020","journal-title":"Circulation"},{"key":"B7","doi-asserted-by":"publisher","first-page":"775","DOI":"10.1093\/qjmed\/hcu024","article-title":"Parkinson\u2019s disease and pseudo-ventricular tachycardia","volume":"107","author":"Sawhney","year":"2014","journal-title":"QJM"},{"key":"B8","doi-asserted-by":"publisher","first-page":"1611","DOI":"10.1111\/pace.15094","article-title":"Spontaneous conversion of a long RP to short RP tachycardia: what is the mechanism?","volume":"47","author":"Allamsetty","year":"2024","journal-title":"Pacing Clin Electrophysiol"}],"container-title":["Frontiers in Pediatrics"],"original-title":[],"link":[{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fped.2025.1643670\/full","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,1,12]],"date-time":"2026-01-12T08:11:19Z","timestamp":1768205479000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fped.2025.1643670\/full"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,1,12]]},"references-count":8,"alternative-id":["10.3389\/fped.2025.1643670"],"URL":"https:\/\/doi.org\/10.3389\/fped.2025.1643670","relation":{},"ISSN":["2296-2360"],"issn-type":[{"value":"2296-2360","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,1,12]]},"article-number":"1643670"}}