<h2 class="section-title u-h3 u-margin-l-top u-margin-xs-bottom">Abstract</h2> <div id="as0005"> <h3 class="u-h4 u-margin-m-top u-margin-xs-bottom" id="st0010">Background/purpose</h3> <p id="sp0060">Identification of the culprit lesion in patients with non-ST elevation<span> </span><a href="https://www.sciencedirect.com/topics/medicine-and-dentistry/acute-coronary-syndrome" title="Learn more about acute coronary syndrome from ScienceDirect's AI-generated Topic Pages" class="topic-link">acute coronary syndrome</a><span> (NSTE-ACS) allows appropriate <a href="https://www.sciencedirect.com/topics/medicine-and-dentistry/heart-muscle-revascularization" title="Learn more about coronary revascularization from ScienceDirect's AI-generated Topic Pages" class="topic-link">coronary revascularization</a> but may be unclear in patients with multivessel <a href="https://www.sciencedirect.com/topics/medicine-and-dentistry/coronary-artery-disease" title="Learn more about coronary disease from ScienceDirect's AI-generated Topic Pages" class="topic-link">coronary disease</a> (MVD). Therefore, we investigated the rate of culprit lesion identification during coronary <a href="https://www.sciencedirect.com/topics/medicine-and-dentistry/angiography" title="Learn more about angiography from ScienceDirect's AI-generated Topic Pages" class="topic-link">angiography</a> in NSTE-ACS and multivessel disease.</span></p> </div> <div id="as0010"> <h3 class="u-h4 u-margin-m-top u-margin-xs-bottom" id="st0015">Methods/materials</h3> <p id="sp0065">Consecutive patients presenting with NSTE-ACS and MVD, between January 2012 and December 2016 were evaluated. Coronary angiograms,<span> </span><a href="https://www.sciencedirect.com/topics/medicine-and-dentistry/intravascular-imaging" title="Learn more about intravascular imaging from ScienceDirect's AI-generated Topic Pages" class="topic-link">intravascular imaging</a><span>, and ECGs were analyzed for culprit lesion identification. Long-term clinical outcomes in terms of <a href="https://www.sciencedirect.com/topics/medicine-and-dentistry/major-adverse-cardiac-event" title="Learn more about major adverse cardiac events from ScienceDirect's AI-generated Topic Pages" class="topic-link">major adverse cardiac events</a> (MACE) and mortality were reported in patients with or without culprit identification.</span></p> </div> <div id="as0015"> <h3 class="u-h4 u-margin-m-top u-margin-xs-bottom" id="st0020">Results</h3> <p id="sp0070"><span>A total of 1107 patients with NSTE-ACS and MVD were included in the analysis, 310 (28.0%) with <a href="https://www.sciencedirect.com/topics/medicine-and-dentistry/unstable-angina" title="Learn more about unstable angina from ScienceDirect's AI-generated Topic Pages" class="topic-link">unstable angina</a> and 797 (72.0%) with non-ST elevation myocardial infarction. The culprit lesion was angiographically identified in 952 (86.0%) patients, while no clear culprit lesion was found in 155 (14.0%) patients. ECG analysis allowed to predict the location of the culprit vessel with low sensitivity (range 28.4%–36.7%) and high specificity (range 90.6%–96.5%). Higher lesion complexity was associated with inability to identify the culprit. Intravascular imaging was applied in 55 patients and helped to identify the culprit lesion in 53 patients (96.4%). There was no difference in all-cause mortality (21.4% vs. 25.8%, </span><em>p</em><span> </span>= 0.24) and MACE (39.2% vs. 47.6%,<span> </span><em>p</em><span> </span>= 0.07) between the cohorts with or without culprit lesion identification by angiography.</p> </div> <div id="as0020"> <h3 class="u-h4 u-margin-m-top u-margin-xs-bottom" id="st0025">Conclusions</h3> <p id="sp0075">The culprit lesion appeared unclear by<span> </span><a href="https://www.sciencedirect.com/topics/medicine-and-dentistry/coronary-angiography" title="Learn more about coronary angiography from ScienceDirect's AI-generated Topic Pages" class="topic-link">coronary angiography</a><span> </span>in >10% of patients with NSTE-ACS and MVD. Complementary invasive imaging substantially enhanced the diagnostic accuracy of culprit lesion detection.</p> </div>