en Clinical Medicine Clinical Medicine مقاله پژوهشی Original Research Article <span style="font-size:10pt"><span new="" roman="" style="font-family:" times=""><b><span style="background:#2d7f8f"><span style="color:white">Background & Objective: </span></span></b><b>&nbsp;</b><span style="font-size:9.0pt">Clinical outcomes of IHD depend on various factors, and coronary collateral circulation (CCC) development has recently been studied more. This study assessed blood groups&#39; effect on CCC formation and patency.<span style="color:black"></span></span></span></span><br> <span style="font-size:10pt"><span new="" roman="" style="font-family:" times=""><b><span style="background:#2d7f8f"><span style="color:white"><span style="letter-spacing:-.1pt">&nbsp;Materials & Methods:</span></span></span></b> &nbsp;<span style="font-size:9.0pt">In this retrospective study, all patients From January 2021 to August 2022, who had been hospitalized in the cardiac care unit of Shahid Madani </span><span style="font-size:9.0pt">C</span><span style="font-size:9.0pt">ardiology </span><span style="font-size:9.0pt">H</span><span style="font-size:9.0pt">ospital in Tabriz, Iran, were studied.</span><span style="font-size:9.0pt"> ABO blood group typing was done with the Sinagene blood group determining kit. </span><span style="font-size:9.0pt">Collateral coronary circulation was assessed based on the Rentrop-Cohen grading scale for coronary arteries with 100% occlusion (CTO).</span></span></span><br> <span style="font-size:10pt"><span new="" roman="" style="font-family:" times=""><b><span lang="EN-IN" style="background:#2d7f8f"><span style="color:white">Results: </span></span></b><span style="font-size:9.0pt">168 of 200 enrolled patients had well, and 32 had poor CCCs based on Rentrop scales. A⁺ blood groups were significantly more prevalent in patients with a good Rentrop scale, and A^-, B^-and AB^- blood groups were significantly more prevalent in the poor CCC group. 21 patients in poor Rentrop and 68 in the good Rentrop group had hypertension (<i>P = 0.009</i>). Seventeen patients in the poor and 55 in the good Rentrop groups had DM (<i>P = 0.028</i>). The history of chronic kidney disease in poor Rentrop patients with 12 cases was significantly more than the good Rentrop group with 4 cases (<i>P=0.000</i>). The two groups had a significant difference in HLP prevalence (<i>0.026</i>).</span></span></span><br> <span style="font-size:10pt"><span new="" roman="" style="font-family:" times=""><b>&nbsp;</b><b><span style="background:#2d7f8f"><span style="color:white">Conclusion: </span></span></b><b>&nbsp;</b><span style="font-size:9.0pt">This study showed DM, hyperlipidemia, hypertension, and A^-, AB^- and B^- blood groups were strong predictors of poor and A⁺ for good CCC development.</span></span></span><br> &nbsp; Coronary collateral circulation, RH blood type, O blood group, Non-O blood groups 209 218 http://journal.zums.ac.ir/browse.php?a_code=A-10-6876-1&slc_lang=en&sid=1 Amirhossein Heidari amhohe@gmail.com 5200319475328460089423 5200319475328460089423 Yes Cardiovascular Research Centre, School of Medicine, Zanjan University of Medical Sciences, Zanjan, Iran Vahid Toupchi Khosroshahi toupchi.vahid@zums.ac.ir 5200319475328460089424 5200319475328460089424 No 1 Cardiovascular Research Centre, School of Medicine, Tabriz University of Medical Science, Tabriz, Iran Naser aslanabadi aslanabadin@gmail.com 5200319475328460089425 5200319475328460089425 No 1 Cardiovascular Research Centre, School of Medicine, Tabriz University of Medical Science, Tabriz, Iran Ahmad Separham a_separham2005@yahoo.com 5200319475328460089426 5200319475328460089426 No 1 Cardiovascular Research Centre, School of Medicine, Tabriz University of Medical Science, Tabriz, Iran Hamidreza Fallahabadi fallah.hamidreza@yahoo.com 5200319475328460089427 5200319475328460089427 No 2 Department of cardiology, School of Medicine, Zanjan University of Medical Sciences, Zanjan, Iran