{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,21]],"date-time":"2026-08-21T10:25:50Z","timestamp":1787307950473,"version":"build-2736575974"},"reference-count":13,"publisher":"Wiley","issue":"1","license":[{"start":{"date-parts":[[2026,8,21]],"date-time":"2026-08-21T00:00:00Z","timestamp":1787270400000},"content-version":"vor","delay-in-days":232,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"},{"start":{"date-parts":[[2026,1,1]],"date-time":"2026-01-01T00:00:00Z","timestamp":1767225600000},"content-version":"tdm","delay-in-days":0,"URL":"http:\/\/doi.wiley.com\/10.1002\/tdm_license_1.1"}],"content-domain":{"domain":["onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["Case Reports in Pediatrics"],"published-print":{"date-parts":[[2026,1]]},"abstract":"<jats:p>Idiopathic atrial flutter (AFL) is an uncommon supraventricular tachyarrhythmia in early infancy. When sustained, AFL may lead to tachycardia\u2010induced cardiomyopathy (TIC), a potentially reversible cause of ventricular dysfunction after rhythm control. We report a 3\u2010month\u2010old boy in whom severe TIC was detected incidentally at a routine infant health checkup despite minimal symptoms. The examining pediatrician noted persistent age\u2010inappropriate tachycardia and referred the infant urgently. On admission, the ventricular rate fluctuated between 160 and 240\u2009beats\/min, likely reflecting variable atrioventricular conduction. Chest radiography showed marked cardiomegaly. Echocardiography revealed a severely dilated left ventricle (left ventricular end\u2010diastolic dimension 41\u2009mm; Z\u2010score +7.3) with diffuse hypokinesis and markedly reduced systolic function (left ventricular ejection fraction approximately 20%), consistent with advanced TIC. Adenosine triphosphate transiently induced atrioventricular block and unmasked typical flutter waves, confirming AFL. Synchronized direct\u2010current cardioversion (1\u2009J\/kg) immediately restored sinus rhythm, followed by standard heart failure therapy. Rapid reverse remodeling was documented quantitatively, with regression of cardiomegaly and normalization of ventricular size and function. The infant was discharged on Day 25 and remained well without recurrence at follow\u2010up. This case highlights that AFL in infancy can be clinically subtle while causing profound TIC and underscores the importance of careful heart rate assessment during infant health supervision.<\/jats:p>","DOI":"10.1155\/crpe\/4811651","type":"journal-article","created":{"date-parts":[[2026,8,21]],"date-time":"2026-08-21T09:46:40Z","timestamp":1787305600000},"update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Idiopathic Atrial Flutter With Tachycardia\u2010Induced Cardiomyopathy Detected at a Routine Infant Health Checkup: A Case Report"],"prefix":"10.1155","volume":"2026","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6513-2942","authenticated-orcid":false,"given":"Toshinobu","family":"Ifuku","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fumito","family":"Wakamatsu","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Keigo","family":"Nakatani","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2026,8,21]]},"reference":[{"key":"e_1_2_12_1_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.jacc.2006.04.091"},{"key":"e_1_2_12_2_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.hrthm.2014.04.023"},{"key":"e_1_2_12_3_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.jacc.2019.02.045"},{"key":"e_1_2_12_4_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.pedneo.2019.04.002"},{"key":"e_1_2_12_5_2","doi-asserted-by":"publisher","DOI":"10.3390\/jcm13113313"},{"key":"e_1_2_12_6_2","doi-asserted-by":"publisher","DOI":"10.1016\/s0002-8703(97)70224-2"},{"key":"e_1_2_12_7_2","doi-asserted-by":"publisher","DOI":"10.1536\/ihj.39.287"},{"key":"e_1_2_12_8_2","doi-asserted-by":"publisher","DOI":"10.1111\/ped.15714"},{"key":"e_1_2_12_9_2","doi-asserted-by":"publisher","DOI":"10.3390\/jcm14197126"},{"key":"e_1_2_12_10_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.jemermed.2015.10.005"},{"key":"e_1_2_12_11_2","doi-asserted-by":"publisher","DOI":"10.1186\/s12887-020-02259-7"},{"key":"e_1_2_12_12_2","doi-asserted-by":"publisher","DOI":"10.1186\/s13052-023-01542-4"},{"key":"e_1_2_12_13_2","doi-asserted-by":"publisher","DOI":"10.1161\/01.cir.0000436140.77832.7a"}],"container-title":["Case Reports in Pediatrics"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1155\/crpe\/4811651","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/full-xml\/10.1155\/crpe\/4811651","content-type":"application\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1155\/crpe\/4811651","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,8,21]],"date-time":"2026-08-21T09:46:41Z","timestamp":1787305601000},"score":1,"resource":{"primary":{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/10.1155\/crpe\/4811651"}},"subtitle":[],"editor":[{"given":"Baisakhi","family":"Banerjee","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"editor"}]}],"short-title":[],"issued":{"date-parts":[[2026,1]]},"references-count":13,"journal-issue":{"issue":"1","published-print":{"date-parts":[[2026,1]]}},"alternative-id":["10.1155\/crpe\/4811651"],"URL":"https:\/\/doi.org\/10.1155\/crpe\/4811651","archive":["Portico"],"relation":{},"ISSN":["2090-6803","2090-6811"],"issn-type":[{"value":"2090-6803","type":"print"},{"value":"2090-6811","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,1]]},"assertion":[{"value":"2026-04-19","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2026-08-01","order":2,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2026-08-21","order":3,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}],"article-number":"4811651"}}