{"id":282,"date":"2013-02-03T18:14:53","date_gmt":"2013-02-03T23:14:53","guid":{"rendered":"http:\/\/www.electricant.net\/ekg\/?p=282"},"modified":"2013-02-24T18:16:20","modified_gmt":"2013-02-24T23:16:20","slug":"strip-19","status":"publish","type":"post","link":"https:\/\/www.electricant.net\/ekg\/strip-19\/","title":{"rendered":"Strip 19"},"content":{"rendered":"<h1>paced rhythm<\/h1>\n<p><a class=\"MagicZoomPlus\" href=\"http:\/\/electricant.net\/ekg\/striptease\/strip19.jpg\"><br \/>\n<img decoding=\"async\" alt=\"\" src=\"http:\/\/electricant.net\/ekg\/striptease\/thumb600\/strip19.jpg\" \/><\/a><\/p>\n<p><strong>First Glance:<\/strong><\/p>\n<p>From across the room it looks like a raging rapid narrow-complex tachycardia, or possibly some kind of repetitive motion artifact.<\/p>\n<p><strong>Discussion:<\/strong><\/p>\n<p>The striking lower trace is a &#8216;V&#8217; lead with 160% voltage calibration (obscured by folded corner in this scan). The most obvious finding is regular waves at a hair under 300 bpm. In addition, we can see some regular hiccups in the baseline, best seen in the upper trace: lead II.<\/p>\n<p>With the baseline a little more sedated in lead II this allows us to better appreciate the regular wide complexes @ 50 bpm. Just before each of these in the upper trace is a sharp ultra-narrow S which is most consistent with a ventricular pacing spike (marked with the magenta triangles). The fact that they are\u00a0<em>exactly<\/em>\u00a01200 ms apart across the entire strip is consistent with exogenous pacing.<\/p>\n<p><img decoding=\"async\" alt=\"\" src=\"http:\/\/electricant.net\/ekg\/striptease\/thumb600\/strip19a.jpg\" \/><\/p>\n<p>Where are those high-speed waves coming from? Atrial flutter comes to mind. If we doubted the pacing theory we might wonder if this is atrial flutter with a high-grade \u00a0block (this would be about 6:1, which does happen) but the atrial waves (marked here with the blue triangles) are not synchronized to the ventricular waves.<\/p>\n<p>When we look closely at the upper trace&#8217;s rapid narrow spikes they sometimes look suspicious for pacing spikes. However, far and away the most likely possibility is that this is artifact. Some motion artifacts from vibrating chest-PT beds, machinery, electrical equipment, etc, can give similar appearances.<\/p>\n<p><strong>Final Impression?<\/strong><\/p>\n<p>Ventricular pacing with 100% capture at 50 bpm, with marked regular artifact.<\/p>\n<p><strong>Management implications:<\/strong><\/p>\n<p>If the patient has symptomatic bradycardia with a pacer, it&#8217;s a little more interesting. Is it a pacer malfunction, or underpacing? Atropine isn&#8217;t going to do squat in the setting of 3rd degree block. I&#8217;d guess that sympathomimetics and inotropes would do little either. If this is a patient in distress, then this man might need a magnet and some external pacing while you&#8217;re waiting for the cardiologist and the interrogator.<\/p>\n<p><strong>\u00a0The Take-home Point:<\/strong><\/p>\n<p>This tele alarm was auto-interpreted as a tachycardia of 214 bpm, which it clearly isn&#8217;t.<\/p>\n<p>Be wary of all automated rhythm interpretations. I find the interpretations generated by the 12L machines and the telemetry boxes alike are best treated like differentials from a medical student (this author included). You should consider them seriously because they may pick up on something you didn&#8217;t, but be highly skeptical. For best sensitivity, look at the auto-interpretation <em>after<\/em> you have already come to your own conclusions (or given up) as you may miss the correct diagnosis due to &#8216;satisfaction of search&#8217; error.<\/p>\n<p>&nbsp;<\/p>\n<p><em><a href=\"http:\/\/www.electricant.net\/ekg\/wp-content\/uploads\/2013\/01\/2purple_star.jpg\"><img loading=\"lazy\" decoding=\"async\" alt=\"2purple_star\" src=\"http:\/\/www.electricant.net\/ekg\/wp-content\/uploads\/2013\/01\/2purple_star.jpg\" width=\"35\" height=\"18\" \/><\/a>Two star strip. The meat and potatoes.<\/em><\/p>\n<h1>&#8212;&gt; see the <a title=\"Next Strip\" href=\"http:\/\/www.electricant.net\/ekg\/striptease\/strip20.htm\">next strip<\/a><\/h1>\n","protected":false},"excerpt":{"rendered":"<p>paced rhythm First Glance: From across the room it looks like a raging rapid narrow-complex tachycardia, or possibly some kind of repetitive motion artifact. Discussion: The striking lower trace is a &#8216;V&#8217; lead with 160% voltage calibration (obscured by folded corner in this scan). The most obvious finding is regular waves at a hair under &#8230;<a class=\"post-readmore\" href=\"https:\/\/www.electricant.net\/ekg\/strip-19\/\">read more<\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[2],"tags":[3],"class_list":["post-282","post","type-post","status-publish","format-standard","hentry","category-cases","tag-2star"],"_links":{"self":[{"href":"https:\/\/www.electricant.net\/ekg\/wp-json\/wp\/v2\/posts\/282","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.electricant.net\/ekg\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.electricant.net\/ekg\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.electricant.net\/ekg\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.electricant.net\/ekg\/wp-json\/wp\/v2\/comments?post=282"}],"version-history":[{"count":14,"href":"https:\/\/www.electricant.net\/ekg\/wp-json\/wp\/v2\/posts\/282\/revisions"}],"predecessor-version":[{"id":284,"href":"https:\/\/www.electricant.net\/ekg\/wp-json\/wp\/v2\/posts\/282\/revisions\/284"}],"wp:attachment":[{"href":"https:\/\/www.electricant.net\/ekg\/wp-json\/wp\/v2\/media?parent=282"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.electricant.net\/ekg\/wp-json\/wp\/v2\/categories?post=282"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.electricant.net\/ekg\/wp-json\/wp\/v2\/tags?post=282"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}