Coronary artery aneurysm or ectasia (CAAE) is a term that includes both coronary artery ectasia (CAE) and coronary artery aneurysm (CAA), despite distinct phenotypes and definitions. This anomaly can be found in 0.15–5.3% of coronary angiography. CAE is a diffuse dilatation of the coronary artery at least 1.5 times wider than the diameter of the normal coronary artery in a patient with a length of over 20 mm or greater than one-third of the vessel. CAE can be further subdivided into diffuse and focal dilations by the number and the length of the dilated vessels. Histologically, it presents with extensive destruction of musculoelastic elements, marked degradation of collagen and elastic fibers, and disruption of the elastic lamina. Conversely, CAA is a focal lesion manifesting as focal dilatation, which can be fusiform (if the longitudinal diameter is greater than the transverse) or saccular (if the longitudinal diameter is smaller than the transverse). Giant CAA is defined as a 4-fold enlargement of the vessel diameter and is observed in only 0.02% of patients after coronary. An aneurysmal lesion can be either single or multiple. It can be either a congenital or acquired phenomenon. The pathophysiological mechanisms responsible for the formation of CAAE are not well understood. Atherosclerosis is the most common etiology of CAAE in adults, while Kawasaki disease is the most common in children. Other etiological factors include systemic connective tissue diseases, infectious diseases, vasculitis, congenital anomalies, genetic factors, and idiopathic CAA. Invasive assessment of CAAE is based on coronary angiography. Coronary computed tomography (CT) is a noninvasive method that enables accurate evaluation of aneurysm size and location. The most common complications are coronary spasm, local thrombosis, distal embolization, coronary artery rupture, and compression of adjacent structures by giant coronary aneurysms. The approach to each patient with CAAE should depend on the severity of symptoms, anatomical structure, size, and location of the aneurysm. Treatment methods should be carefully considered to avoid possible complications of CAAE. Simultaneously, we should not unnecessarily expose the patient to the risk of intervention or surgical treatment. Patients can be offered conservative or invasive treatment. However, there are still numerous controversies and ambiguities regarding the etiology, prognosis, and treatment of patients with coronary artery aneurysms. This study summarizes the current knowledge about this disease’s etiology, pathogenesis, and management.

Introduction: Major retroperitoneal arterial bleeding may remain clinically difficult to recognize when vital signs are initially stable. Case presentation: We report the case of a 67-year-old man who developed progressive abdominal and right groin pain radiating to the ipsilateral flank, accompanied by two episodes of vomiting and an early hemoglobin (Hb) and hematocrit decline on the first postoperative day after right-sided direct anterior total hip arthroplasty (THA). Despite the absence of hemodynamic instability, computed tomography angiography (CTA) demonstrated active contrast extravasation from the right external iliac artery (EIA) with a large retroperitoneal hematoma. CTA localized the bleeding source and enabled immediate endovascular treatment planning. Subsequent angiography confirmed active extravasation from the right EIA, and a covered stent–graft was deployed through ultrasound-guided superficial femoral artery access, achieving complete exclusion of the bleeding source with preserved arterial patency. The subsequent Hb nadir and transfusion were interpreted as reflecting preceding retroperitoneal blood loss rather than persistent bleeding, because follow-up CTA showed a stable hematoma without active extravasation. The patient was discharged in stable condition, and 1-month duplex ultrasound and following 3-month CTA confirmed stent–graft patency. Discussion: This case highlights the diagnostic mismatch that may occur between substantial retroperitoneal blood loss and initially reassuring hemodynamic findings. When progressive abdominal or groin symptoms are accompanied by a serial, otherwise unexplained Hb decline, CTA may be more informative than DUS for suspected deep pelvic bleeding because it can identify active extravasation, define hematoma extent, assess alternative abdominopelvic causes, and support treatment planning. In anatomically suitable lesions, covered stent–graft repair can rapidly control hemorrhage while preserving EIA patency. Conclusions: Stable vital signs do not exclude major retroperitoneal arterial bleeding after direct anterior THA. Progressive abdominal or groin pain with early postoperative Hb decline should raise suspicion for occult vascular injury, for which CTA can provide rapid diagnosis and guide immediate endovascular management.