{"id":38125,"date":"2013-08-26T16:00:57","date_gmt":"2013-08-26T20:00:57","guid":{"rendered":"http:\/\/blogs.nejm.org\/cardioexchange\/?post_type=voices&#038;p=38125"},"modified":"2013-08-26T16:19:03","modified_gmt":"2013-08-26T20:19:03","slug":"new-subcutaneous-icd-said-to-pose-existential-crisis-for-older-icds","status":"publish","type":"post","link":"https:\/\/blogs.nejm.org\/cardioexchange\/2013\/08\/26\/new-subcutaneous-icd-said-to-pose-existential-crisis-for-older-icds\/","title":{"rendered":"New Subcutaneous ICD Said to Pose &#8216;Existential Crisis&#8217; for Older ICDs"},"content":{"rendered":"<p><a title=\"Subcutaneous ICD Gains FDA Approval\" href=\"http:\/\/blogs.nejm.org\/cardioexchange\/news\/subcutaneous-icd-gains-fda-approval\/\">Last year the FDA approved Boston Scientific&#8217;s subcutaneous ICD (S-ICD)<\/a>, the first ICD that doesn&#8217;t use transvenous leads. Those leads are the source of many sophisticated pacing features in today&#8217;s ICDs, but they are also the main source of ICD-related complications.<\/p>\n<p>FDA approval of the S-ICD was based on a pivotal trial designed to assess the device&#8217;s safety and effectiveness. Results of the trial <a href=\"http:\/\/circ.ahajournals.org\/content\/128\/9\/944.abstract\">have\u00a0now been published in\u00a0<em>Circulation<\/em><\/a>. In this nonrandomized trial, the S-ICD was successfully implanted in 314 patients out of 321 in whom the implantation was attempted.<\/p>\n<p>The S-ICD easily met the prespecified primary safety and efficacy endpoints:<\/p>\n<ul>\n<li>Primary safety end point (180-day complication-free rate): 99%. The lower confidence limit of 87.9% surpassed the\u00a0prespecified performance goal of 79%.<\/li>\n<li>Primary effectiveness end point (the acute induced\u00a0VF\u00a0conversion rate at the time of implantation): 100%, achieved in all of the 304 patients who underwent the full testing protocol,\u00a0&#8220;far exceeding&#8221; the performance goal of 88%. A total of 17 patients were not evaluated for effectiveness, but even if all were deemed failures, the acute\u00a0VF\u00a0conversion rate would still have been well above the lower confidence limit.<\/li>\n<\/ul>\n<p>During the course of followup there were 38 episodes of VT\/VF\u00a0in 21 patients. These were all successfully converted. Overall, 13.1% of patients received an inappropriate shock.<\/p>\n<p>The results, write the authors, &#8220;demonstrate that the S-ICD System is safe and well tolerated as a chronically implanted ICD and is effective in terminating both induced and spontaneous VT\/VF.&#8221;<\/p>\n<p><a href=\"http:\/\/circ.ahajournals.org\/content\/128\/9\/938.extract\">In an accompanying editorial<\/a>, Leslie Saxon writes that the appearance of the S-ICD &#8220;poses a significant existential crisis for the now middle-aged standard, transvenous, and fully featured ICD.&#8221; The S-ICD &#8220;is pared down to 1 essential meaning, purpose, and value: ventricular arrhythmia defibrillation.&#8221;<\/p>\n<p>Although the available data on the S-ICD &#8220;are reassuring and comparable to transvenous ICD success rates,&#8221; she notes that &#8220;the overall number of treated episodes is incredibly small in comparison&#8221; with standard ICDs, which also have much longer followup data.\u00a0In addition, &#8220;a significant limitation from a clinical learning and safety advisory perspective&#8221; is the lack of remote monitoring capability.<\/p>\n<p>Saxon nevertheless suggests that a &#8220;significant percentage&#8221; of potential ICD patients may be candidates for the S-ICD,\u00a0including those with &#8220;prohibitive vascular access issues&#8221; and those at high risk for major infection associated with a transvenous lead.<\/p>\n<p>In an interview, Saxon said that although the S-ICD is a genuine advance in defibrillation technology, it also represents something of a throwback, as it appears to contradict &#8220;the constant evolutionary course of technology&#8221; in which more features and capabilities are packed into increasingly small spaces with each subsequent generation of technology.<\/p>\n<p>&nbsp;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Last year the FDA approved Boston Scientific&#8217;s subcutaneous ICD (S-ICD), the first ICD that doesn&#8217;t use transvenous leads. Those leads are the source of many sophisticated pacing features in today&#8217;s ICDs, but they are also the main source of ICD-related complications. FDA approval of the S-ICD was based on a pivotal trial designed to assess [&hellip;]<\/p>\n","protected":false},"author":196,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[13],"tags":[543,449,1484,898,1937],"class_list":["post-38125","post","type-post","status-publish","format-standard","hentry","category-electrophysiology","tag-icd","tag-inappropriate-shocks","tag-s-icd","tag-scd","tag-vtvf"],"_links":{"self":[{"href":"https:\/\/blogs.nejm.org\/cardioexchange\/wp-json\/wp\/v2\/posts\/38125","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blogs.nejm.org\/cardioexchange\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blogs.nejm.org\/cardioexchange\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blogs.nejm.org\/cardioexchange\/wp-json\/wp\/v2\/users\/196"}],"replies":[{"embeddable":true,"href":"https:\/\/blogs.nejm.org\/cardioexchange\/wp-json\/wp\/v2\/comments?post=38125"}],"version-history":[{"count":0,"href":"https:\/\/blogs.nejm.org\/cardioexchange\/wp-json\/wp\/v2\/posts\/38125\/revisions"}],"wp:attachment":[{"href":"https:\/\/blogs.nejm.org\/cardioexchange\/wp-json\/wp\/v2\/media?parent=38125"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blogs.nejm.org\/cardioexchange\/wp-json\/wp\/v2\/categories?post=38125"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blogs.nejm.org\/cardioexchange\/wp-json\/wp\/v2\/tags?post=38125"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}