CD34 and non-obstructive coronary artery disease: Intracoronary CD34+ cell therapy for the treatment of coronary endothelial dysfunction in patients with angina and nonobstructive coronary arteries (IMPROvE-CED) trial was a prospective, open-label, single-center, single-arm study published in 2022 done by Corban et al. [4], showed that intracoronary autologous CD34+ cell therapy could enhance coronary microvascular endothelial function in Non-obstructive coronary artery disease (NOCAD) patients with invasive endothelial dysfunction and refractory angina despite maximum tolerated conventional medical treatment.