BACKGROUND: Trans-radial (TRA) access has become increasingly prevalent in neurointervention. Nonetheless, mediastinal hematoma after TRA is an infrequent yet grave complication associated with a notably elevated mortality rate. While our review found no reported mediastinal hematoma cases managed conservatively within neuro-interventional literature, similar complications are documented in cardiac and vascular interventional radiology, indicating its potential occurrence across disciplines.
METHODS: Carotid computed tomography angiography (CTA) showed calcified plaques with stenosis (Left: Severe, Right: Moderate) in the bilateral internal carotid arteries (ICAs) of an 81-year-old male presented with paroxysmal weakness in the right upper limb. Dual antiplatelet therapy with aspirin and clopidogrel was administered. On day 7, DSA of the bilateral ICAs was performed via TRA. Post-DSA, the patient experienced transient loss of consciousness, chest tightness, and other symptoms without ECG or MRI abnormalities. Hemoglobin level decreased from 110 g/L to 92 g/L. Iodinated contrast-induced laryngeal edema was suspected, and the patient was treated with intravenous methylprednisolone. Neck CT indicated a possible mediastinal hemorrhage, which chest CTA confirmed. The patient\'s treatment plan involved discontinuing antiplatelet medication as a precautionary measure against the potential occurrence of an ischemic stroke instead of the utilization of a covered stent graft and surgical intervention. Serial CTs revealed hematoma absorption. Discharge CT showed a reduced hematoma volume of 35 × 45 mm.
CONCLUSIONS: This case underscores the need for timely identification and precise manipulation of guidewires and guide-catheters through trans-radial access. The critical components of successful neuro-interventional techniques include timely examination, rapid identification, proper therapy, and diligent monitoring.

Carotid artery puncture is a common complication of internal jugular vein (IJV) catheterization. However, there are few reports about an aneurysm from the carotid artery that can develop into an occult mediastinal hematoma, leading to airway compression. In this case study, we present the case of a 71-year-old male who experienced an aneurysm and delayed mediastinal hematoma, ultimately resulting in airway compression after right jugular line insertion. Our findings highlight the importance of not only addressing local hematoma formation at the puncture site promptly, but also recognizing the potential for aneurysm extension into the mediastinum and the formation of an occult hematoma, which can lead to airway compression. Additionally, we provide a summary of landmark technique precautions that can help reduce the occurrence of such severe complications.

To provide a comprehensive introduction of mediastinal hematoma.
Mediastinal hematoma is a rare complication that is usually not considered in the differential diagnosis of chest pain after cardiac catheterization.
From January 1, 2006, to December 31, 2013, at Fuwai Hospital, 126,265 patients underwent coronary angiography (CAG); 121,215 of them underwent CAG via the radial artery. Ultimately, 10 patients with mediastinal hematoma due to cardiac catheterization were included. Patients\' clinical characteristics, diagnosis, treatment, and prognosis were retrospectively analyzed.
The incidences of mediastinal hematoma in cardiac catheterization and transradial cardiac catheterization were 0.79‱ and 0.74‱, respectively. A super slide hydrophilic guidewire was used in all 10 patients with mediastinal hematoma. These patients felt chest pain and dyspnea during/after the procedure, and computed tomography (CT) was used to diagnose mediastinal hematoma. Among them, two patients had a neck hematoma. The post-procedural hemoglobin level decreased substantially in all patients. Antiplatelet therapy was discontinued for 8-20 days in three patients without stents implanted, and then only oral aspirin was prescribed. Aspirin was transiently discontinued for 2 days in one patient undergoing percutaneous coronary intervention. The others continued taking dual antiplatelet drugs. Two patients received blood transfusion. There was no case of stent thrombosis, and surgery was not indicated for any patient. No complication was observed after discharge during the 9.0 ± 2.5-year follow-up.
CT should be performed as early as possible in patients with suspected mediastinal hematoma. The prognosis of mediastinal hematoma is usually good with early diagnosis and suitable therapy.

Spontaneous mediastinal hematoma is exceedingly rare. We described such a case of a 61-year-old male with a posterior mediastinal hematoma from ruptured small aneurysm, which was ascertained via contrast-enhanced computed tomography examination. Subsequent super-selective angiography of left gastric artery revealed a ruptured aneurysm with contrast medium leakage, feeding vessels respectively from caudal and cranial artery. The left gastric artery branch caudally feeding aneurysm was successfully occluded, while cranially feeding artery from the branch of left bronchial artery failed to embolize due to complex anatomic factor. Our management still yields to a satisfactory outcome.