{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,9,17]],"date-time":"2025-09-17T07:59:33Z","timestamp":1758095973288,"version":"3.44.0"},"reference-count":10,"publisher":"Wiley","issue":"9","license":[{"start":{"date-parts":[[2025,6,25]],"date-time":"2025-06-25T00:00:00Z","timestamp":1750809600000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"}],"content-domain":{"domain":["onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["Pacing Clinical Electrophis"],"published-print":{"date-parts":[[2025,9]]},"abstract":"<jats:title>ABSTRACT<\/jats:title><jats:sec><jats:title>Introduction<\/jats:title><jats:p>Dual\u2010chamber pacemakers incorporate proprietary algorithms to optimize atrioventricular (AV) synchronization and prevent pacemaker\u2010mediated arrhythmias. Patients have recently presented to our center with severe exercise intolerance due to the early onset of 2:1 AV block caused by Biotronik's Auto\u2010PVARP and 2:1 Lock\u2010in protection algorithms. This study evaluates the relationship of these algorithms to low 2:1 block rates in a large cohort of remotely monitored pacemaker patients.<\/jats:p><\/jats:sec><jats:sec><jats:title>Methods<\/jats:title><jats:p>We troubleshooted the patients with symptomatic exercise intolerance. We then performed an observational study using remote monitoring data from 895 patients implanted with Biotronik pacemakers, programmed in DDD(R) mode with the Auto\u2010PVARP algorithm activated. We analyzed PVARP settings, 2:1 block rates, and their relationship with age\u2010predicted maximal sinus rates.<\/jats:p><\/jats:sec><jats:sec><jats:title>Results<\/jats:title><jats:p>Among the 895 remotely monitored patients, the majority had significantly prolonged PVARP settings, lowering their 2:1 block rate. At the most recent transmission, only 37% had a PVARP \u2264225\u00a0ms, while 63% had longer values (275\u2013375\u00a0ms), leading to lower 2:1 block thresholds. The 2:1 block rate was below the age\u2010predicted maximal sinus rate in 48% of patients, suggesting a high risk of pacing\u2010induced exercise limitations. The prolonged PVARP was largely driven by Auto\u2010PVARP extensions, often without documented pacemaker\u2010mediated tachycardia (PMT). These findings indicate that a significant proportion of pacemaker\u2010dependent patients may unknowingly experience pacing\u2010related exercise intolerance.<\/jats:p><\/jats:sec><jats:sec><jats:title>Conclusion<\/jats:title><jats:p>The Biotronik Auto\u2010PVARP algorithm frequently extends the refractory period, lowering the threshold for 2:1 block and potentially limiting exercise capacity in active patients. Disabling Auto\u2010PVARP and setting a fixed, shorter PVARP may improve exercise tolerance.<\/jats:p><\/jats:sec>","DOI":"10.1111\/pace.70006","type":"journal-article","created":{"date-parts":[[2025,6,25]],"date-time":"2025-06-25T06:34:28Z","timestamp":1750833268000},"page":"953-958","update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Hitting the Wall: The Hidden Challenge of 2:1 Block in Pacemaker Patients"],"prefix":"10.1111","volume":"48","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3348-6548","authenticated-orcid":false,"given":"Marc","family":"Strik","sequence":"first","affiliation":[{"name":"Univ. Bordeaux INSERM CRCTB  Bordeaux France"},{"name":"CHU de Bordeaux Service de Cardiologie\u2010\u00e9lectrophysiologie et stimulation cardiaque INSERM  Bordeaux France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sylvain","family":"Ploux","sequence":"additional","affiliation":[{"name":"Univ. Bordeaux INSERM CRCTB  Bordeaux France"},{"name":"CHU de Bordeaux Service de Cardiologie\u2010\u00e9lectrophysiologie et stimulation cardiaque INSERM  Bordeaux France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Anand","family":"Thiyagarajah","sequence":"additional","affiliation":[{"name":"Univ. Bordeaux INSERM CRCTB  Bordeaux France"},{"name":"CHU de Bordeaux Service de Cardiologie\u2010\u00e9lectrophysiologie et stimulation cardiaque INSERM  Bordeaux France"},{"name":"Centre for Heart Rhythm Disorders University of Adelaide  Adelaide Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lars","family":"van Krimpen","sequence":"additional","affiliation":[{"name":"Univ. Bordeaux INSERM CRCTB  Bordeaux France"},{"name":"CHU de Bordeaux Service de Cardiologie\u2010\u00e9lectrophysiologie et stimulation cardiaque INSERM  Bordeaux France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Pierre","family":"Bordachar","sequence":"additional","affiliation":[{"name":"Univ. Bordeaux INSERM CRCTB  Bordeaux France"},{"name":"CHU de Bordeaux Service de Cardiologie\u2010\u00e9lectrophysiologie et stimulation cardiaque INSERM  Bordeaux France"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"311","published-online":{"date-parts":[[2025,6,25]]},"reference":[{"key":"e_1_2_10_2_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.jelectrocard.2018.08.021"},{"key":"e_1_2_10_3_1","doi-asserted-by":"publisher","DOI":"10.1111\/pace.14663"},{"key":"e_1_2_10_4_1","doi-asserted-by":"publisher","DOI":"10.1111\/j.1540-8159.1988.tb06329.x"},{"key":"e_1_2_10_5_1","doi-asserted-by":"publisher","DOI":"10.1111\/pace.15033"},{"key":"e_1_2_10_6_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.hrthm.2023.12.006"},{"key":"e_1_2_10_7_1","doi-asserted-by":"publisher","DOI":"10.1016\/S0735-1097(00)01054-8"},{"key":"e_1_2_10_8_1","doi-asserted-by":"publisher","DOI":"10.1002\/joa3.12529"},{"key":"e_1_2_10_9_1","doi-asserted-by":"publisher","DOI":"10.1007\/s10840-019-00698-6"},{"key":"e_1_2_10_10_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.jelectrocard.2016.04.004"},{"key":"e_1_2_10_11_1","doi-asserted-by":"publisher","DOI":"10.1093\/europace\/euad358"}],"container-title":["Pacing and Clinical Electrophysiology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1111\/pace.70006","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,9,16]],"date-time":"2025-09-16T09:25:43Z","timestamp":1758014743000},"score":1,"resource":{"primary":{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/10.1111\/pace.70006"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,6,25]]},"references-count":10,"journal-issue":{"issue":"9","published-print":{"date-parts":[[2025,9]]}},"alternative-id":["10.1111\/pace.70006"],"URL":"https:\/\/doi.org\/10.1111\/pace.70006","archive":["Portico"],"relation":{},"ISSN":["0147-8389","1540-8159"],"issn-type":[{"type":"print","value":"0147-8389"},{"type":"electronic","value":"1540-8159"}],"subject":[],"published":{"date-parts":[[2025,6,25]]},"assertion":[{"value":"2025-04-14","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2025-06-16","order":2,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2025-06-25","order":3,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}]}}