A 54-year-old male Han patient was referred to our hospital for a 6-day history of unstable angina on April 2, 2018. He complained of associated palpitation, diaphoresis, and pleuritic chest pain. The patient denied any history of trauma, cough, vomiting, or other constitutional symptoms. He had a 20-pack-year smoking history. His medical history was significant hypertension treated with amlodipine (5 mg/d). He received aspirin (Bayer, Leverkusen, Germany), clopidogrel (Sanofi, Paris, France), and other conventional treatments after admission. At the 3rd day, routine diagnostic coronary angiography revealed subtotal (99%) stenosis in the distal left anterior descending (LAD) coronary artery by the right radial artery approach. Heparin (70–100 U/kg) was administered during the intervention guided by the activated clotting time (ACT; target value of 280–350 seconds). A 6 French EBU3.5 guide catheter (Medtronic, Minneapolis, MN) was advanced over an exchange length 0.035″ hydrophilic J-wire without fluoroscopy, but could not be smoothly delivered to the ascending aorta due to resistance in the tortuous subclavian and the brachiocephalic artery. The distal guidewire was confirmed to be inside the lumen of the guide catheter by fluoroscopy. Therefore, the guidewire was again appropriately positioned in the ascending aorta under fluoroscopy. However, the guidewire's support was poor, and the guide catheter could not advance. Then, the dual-guidewire technique was successfully applied to advance the guide catheter to the left coronary artery (LCA). Finally, PCI was performed smoothly, during which the patient felt some discomfort on his right neck.\nImmediately after the procedure, the patient was transferred to the cardiac care unit (CCU). Five minutes later, he reported an episode of neck and chest discomfort, dyspnea, cough recurrence, and cold sweats. However, sufficient peripheral artery oxygen saturation and normal blood pressure revealed stable hemodynamics. The patient was rapidly administered IV 10 mg furosemide (Jinling Pharmaceutical Co., Zhejiang, CN) for presumed acute left heart failure due to dyspnea, recurrent cough, and subtotal stenosis in LAD. However, the series of discomforts even worsened. Peripheral artery oxygen saturation declined to 90%–92% in room air and the heart rate significantly increased. Finally, careful physical examination showed a right-sided swelling at the base of the patient's neck and the absence of pulmonary rales. Chest fluoroscopy during PCI was promptly performed, which revealed a dramatically widened superior mediastinum (Fig. A).\nTo further clarify this problem, an emergency-enhanced computed tomography (CT) scan was performed, which showed a significant mass in the lower right neck and the anterior mediastinum (Fig. B, C). The mass surrounded the thoracic ascending aorta and the trachea, indicating an anterior mediastinal hematoma. The trachea was severely compressed by the mediastinal hematoma (Fig. C). Coronal CT scan of the chest revealed a small perforation of the subclavian artery (Fig. D). Urgent consultations with the anesthesiologist, and cardiothoracic and vascular surgeons were performed for the evaluation of possible anoxic events and unstable hemodynamics. Emergency endotracheal intubation was suggested, which was declined by the patient himself and his family members.\nDue to worsening dyspnea, the patient was taken to the catheter lab again. With the anesthetist on standby, angiography of the brachiocephalic artery was performed via the right radial route, which revealed a perforation of the proximal right subclavian artery (Fig. A). At the beginning, a suggestion was made to place a covered stent graft. However, the perforation site was extremely close to the carotid artery. It was possible to completely occlude the carotid artery by the covered stent graft, which may cause cerebral infarction and even death. Then, the jailed balloon technique was suggested to prevent carotid artery occlusion. To increase the success rate of the surgery, the femoral route was applied. Then, the patient's recorded ACT was 285 seconds and he was rapidly administered 50 mg IV protamine (First Biochemical Pharmaceutical Co., Shanghai, CN) to reverse the effect of heparin for presumed perforation and hematoma. Two minutes later, the ACT was 173 seconds, and angiography of the brachiocephalic artery was performed by the right femoral route, which revealed reduced extravasation of contrast from the site of vascular perforation. Five minutes later, another 10 mg protamine was provided, which reduced the ACT to 120 seconds. Angiography confirmed the presence of right subclavian artery pseudoaneurysm and the absence of leakage at this moment (Fig. B). The patient had an apparent remission of clinical dyspnea. The patient was transferred to the cardiac care unit (CCU) for close observation.\nThe next day after PCI, aspirin (75 mg/d) and clopidogrel (75 mg/d) were continued. Plain chest computed tomography (CT) was performed to confirm trachea compression alleviation (Fig. C). To avoid lung infection, cefazolin (2 g/d; Jiuxin Pharmaceutical Co., Shenzhen, CN) was prophylactically used for the next 48 hours. The patient was ultimately discharged 5 days later. The patient was advised to continue standard dual antiplatelet therapy for at least 12 months after discharge. Follow-up CT confirmed an almost entire absorption of the mediastinal hematoma 35 days postdischarge on May 15, 2018 (Fig. D). The patient had no chest discomfort in the following 6 months as assessed during outpatient visits.
A 69-year-old man with a history of hypertension, dyslipidemia, and type 2 diabetes mellitus presented with lifestyle-limiting angina. He underwent diagnostic coronary angiography that revealed stenoses of the left anterior descending (LAD) coronary artery, ramus intermedius coronary artery, and the distal right coronary artery (RCA). Coronary artery bypass grafting was recommended, but the patient refused surgery and elected for percutaneous coronary intervention (PCI) instead. Initially, transradial PCI of the LAD and ramus coronary arteries was performed with placement of drug-eluting stents in each vessel. The patient was discharged on aspirin and ticagrelor with a plan for staged coronary intervention of the distal RCA at a later date.\nThree months after the initial coronary intervention, the patient returned for planned PCI of the distal RCA stenosis. Access was again obtained in the right radial artery with a short 6 French slender sheath. After routine diagnostic coronary angiography confirmed a severe stenosis in the distal RCA (), bivalirudin was administered. A 6 French AL 0.75 guide catheter (Medtronic, Minneapolis, MN, USA) was advanced over an exchange length 0.035″ J-wire, but could not be delivered to the ascending aorta due to resistance in the brachiocephalic artery. The guide was removed and exchanged for a 6 French JR 4 guide catheter (Medtronic, Minneapolis, MN, USA), which was easily advanced into the ascending aorta and used to engage the ostium of the RCA without complication. Next, a standard 0.014″ RunThrough coronary guidewire (Terumo, Tokyo, Japan) was placed in the distal RCA, and percutaneous coronary intervention was performed. The lesion was predilated with a 2.0 mm Maverick compliant balloon (Boston Scientific, Marlborough, MA, USA) inflated to 10 ATM, and a Xience Alpine 2.75 × 12 mm cobalt chromium everolimus drug-eluting stent (Abbot Vascular, Abbott Park, IL, USA) was delivered to the lesion and deployed at 16 ATM. There was a good angiographic result of the distal RCA with no residual stenosis (). Immediately following completion of the procedure, the patient reported an episode of chest discomfort, a new cough, bilateral expiratory wheezes, and respiratory stridor. A transient episode of hypotension was noted but resolved without intervention. The patient was rapidly administered IV methylprednisolone, famotidine, diphenhydramine, and inhaled racemic epinephrine for presumed allergic reaction to iodinated contrast. Although his symptoms largely improved, stridor persisted. Urgent otolaryngology consultation was obtained for the evaluation of possible laryngeal edema, but flexible fiber-optic laryngoscopy was unremarkable. Next, chest radiography was promptly obtained, which revealed a markedly widened superior mediastinum ().\nBased on the findings on chest radiography, transesophageal echocardiography (TEE) was urgently performed. Echocardiography revealed no evidence of aortic dissection, but vague echodensities were noted anterior to the right heart suggestive of a hematoma. Thus, computed tomography (CT) of the chest without intravenous contrast was performed to obtain cross-sectional imaging of the mediastinum. The chest CT revealed a large hyperdense region surrounding the trachea suggestive of an anterior mediastinal hematoma, resulting in severe airway compression (). Due to the severity of tracheal compression, the decision was made to perform endotracheal intubation and mechanical ventilation and transfer to the intensive care unit. After intubation, a repeat CT of the chest with administration of intravenous contrast was notable for a small pseudoaneurysm arising from the inferior aspect of the brachiocephalic artery, as well as significant narrowing of the distal trachea below the endotracheal tube ().\nAfter consultation with cardiothoracic and vascular surgery, the decision was made to pursue endovascular repair of the brachiocephalic artery pseudoaneurysm and presumed site of vascular perforation. Access was obtained in the left common femoral artery, and angiography of the brachiocephalic artery was performed, which confirmed the presence of a brachiocephalic artery pseudoaneurysm (). Next, a SupraCore wire (Abbot Vascular, Abbott Park, IL, USA) was placed in the right subclavian artery and a 10 × 40 mm iCAST covered stent (Atrium Medical, Hudson, NH, USA) was deployed across the neck of the pseudoaneurysm. The covered stent was postdilated with a 12 × 20 mm Armada balloon (Abbot Vascular, Abbott Park, IL, USA). Following the intervention, there was an excellent angiographic result with preserved subclavian and carotid runoff (). Aspirin was continued; P2Y12 inhibitors were temporarily withheld.\nDue to persistent tracheal compression after endovascular repair of the brachiocephalic artery, a Tracheobronxane Dumon silicone tracheal stent (Novatech, La Ciotat, France) was inserted by interventional pulmonology to maintain airway patency while the mediastinal hematoma resorbed. Over the ensuring days, serial imaging demonstrated no further enlargement of the mediastinal hematoma, and dual antiplatelet agents were resumed. The tracheal stent was retrieved and removed after 12 days. The patient was ultimately discharged to inpatient rehabilitation on hospital day 19.