{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,13]],"date-time":"2026-06-13T14:45:31Z","timestamp":1781361931806,"version":"3.54.1"},"reference-count":20,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2023,2,23]],"date-time":"2023-02-23T00:00:00Z","timestamp":1677110400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Italian Health Ministry (IRCCS San Raffaele Roma\u2013Ricerca Corrente","award":["#2020\/1"],"award-info":[{"award-number":["#2020\/1"]}]},{"name":"Italian Health Ministry (IRCCS San Raffaele Roma\u2013Ricerca Corrente","award":["MEBIC # 18\/6\/2019"],"award-info":[{"award-number":["MEBIC # 18\/6\/2019"]}]},{"name":"Fondazione Roma","award":["#2020\/1"],"award-info":[{"award-number":["#2020\/1"]}]},{"name":"Fondazione Roma","award":["MEBIC # 18\/6\/2019"],"award-info":[{"award-number":["MEBIC # 18\/6\/2019"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JCM"],"abstract":"<jats:p>Background: The pathology of conduction tissue (CT) and relative arrhythmias in living subjects with cardiac amyloid have never been reported. Aims: To report CT pathology and its arrhythmic correlations in human cardiac amyloidosis. Methods and Results: In 17 out of 45 cardiac amyloid patients, a left ventricular endomyocardial biopsy included conduction tissue sections. It was identified by Aschoff\u2013Monckeberg histologic criteria and positive immunostaining for HCN4. The degree of conduction tissue infiltration was defined as mild when \u226430%, moderate when 30\u201370% and severe when &gt;70% cell area was replaced. Conduction tissue infiltration was correlated with ventricular arrhythmias, maximal wall thickness and type of amyloid protein. Mild involvement was observed in five cases, moderate in three and severe in nine. Involvement was associated with a parallel infiltration of conduction tissue artery. Conduction infiltration correlated with the severity of arrhythmias (Spearman rho = 0.8, p &lt; 0.001). In particular, major ventricular tachyarrhythmias requiring pharmacologic treatment or ICD implantation occurred in seven patients with severe, one patient with moderate and none with mild conduction tissue infiltration. Pacemaker implantation was required in three patients, with complete conduction section replacement. No significant correlation was observed between the degree of conduction infiltration and age, cardiac wall thickness or type of amyloid protein. Conclusions: Amyloid-associated cardiac arrhythmias correlate with the extent of conduction tissue infiltration. Its involvement is independent from type and severity of amyloidosis, suggesting a variable affinity of amyloid protein to conduction tissue.<\/jats:p>","DOI":"10.3390\/jcm12051798","type":"journal-article","created":{"date-parts":[[2023,2,24]],"date-time":"2023-02-24T01:37:52Z","timestamp":1677202672000},"page":"1798","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Infiltration of Conduction Tissue Is a Major Cause of Electrical Instability in Cardiac Amyloidosis"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5748-0725","authenticated-orcid":false,"given":"Andrea","family":"Frustaci","sequence":"first","affiliation":[{"name":"Cellular and Molecular Cardiology Lab, IRCCS L. Spallanzani, Via Portuense 292, 00149 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Romina","family":"Verardo","sequence":"additional","affiliation":[{"name":"Cellular and Molecular Cardiology Lab, IRCCS L. Spallanzani, Via Portuense 292, 00149 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5847-6015","authenticated-orcid":false,"given":"Matteo","family":"Russo","sequence":"additional","affiliation":[{"name":"MEBIC Consortium, San Raffaele Open University, 00166 Rome, Italy"},{"name":"Cellular and Molecular Pathology, IRCCS San Raffaele, 00166 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marina","family":"Caldarulo","sequence":"additional","affiliation":[{"name":"Cellular and Molecular Cardiology Lab, IRCCS L. Spallanzani, Via Portuense 292, 00149 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maria","family":"Alfarano","sequence":"additional","affiliation":[{"name":"Department of Clinical Internal Medicine, Anesthesiology and Cardiovascular Sciences, Sapienza University, 00185 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4708-5120","authenticated-orcid":false,"given":"Nicola","family":"Galea","sequence":"additional","affiliation":[{"name":"Department of Experimental Medicine, Sapienza University, 00185 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fabio","family":"Miraldi","sequence":"additional","affiliation":[{"name":"Department of Clinical Internal Medicine, Anesthesiology and Cardiovascular Sciences, Sapienza University, 00185 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cristina","family":"Chimenti","sequence":"additional","affiliation":[{"name":"Department of Clinical Internal Medicine, Anesthesiology and Cardiovascular Sciences, Sapienza University, 00185 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,2,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1911","DOI":"10.1016\/S0002-9440(10)65064-X","article-title":"Apolipoprotein AI and Transthyretin as Components of Amyloid Fibrils in a Kindred with apoAI Leu178His Amyloidosis","volume":"156","author":"Vital","year":"2000","journal-title":"Am. 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