Yohei Kawatani

Contrast Medium Induced Nephropathy after Endovascular Stent Graft Placement: An Examination of Its Prevalence and Risk Factors

Endovascular stent graft placement has become a major treatment for thoracic and abdominal aneurysms. While endovascular therapy is less invasive than open surgery, it involves the use of a contrast medium. Contrast media can cause renal impairment, a condition termed as contrast-induced nephropathy (CIN). This study sought to evaluate the incidence and risk factors of CIN following endovascular stent graft placement for aortic aneurysm repair. The study included 167 consecutive patients who underwent endovascular stent graft placement in our hospital from October 2013 to June 2014. CIN was diagnosed using the European Society of Urogenital Radiology criteria. Patients with and without CIN were compared. Chi-squared tests, t-tests, and multivariate logistic regression analyses were performed. Thirteen patients (7.8%) developed CIN. Left ventricular dysfunction and intraoperative blood transfusion were significantly more frequent in the CIN group (P = 0.017 and P = 0.032, resp.). Multivariate analysis showed that left ventricular dysfunction had the strongest influence on CIN development (odds ratio 9.34, P = 0.018, and 95% CI = 1.46–59.7). Patients with CIN also experienced longer ICU and hospital stays. Measures to improve renal perfusion flow should be considered for patients with left ventricular dysfunction who are undergoing endovascular stent graft placement.

A case of ruptured aortic arch aneurysm successfully treated by thoracic endovascular aneurysm repair with chimney graft.

We report the case of aortic arch aneurysm rupture treated successfully with thoracic endovascular aneurysm repair (TEVAR) accompanied by aortic arch debranching using the chimney graft technique. A 94-year-old man was transported to the hospital after complaining of chest pain for one day. Contrast-enhanced computed tomographic (CT) images revealed an aortic arch aneurysm rupture. Considering the patients age and postoperative activities of daily living, TEVAR was used. In order to place an indwelling stent graft from the ascending aorta to the periphery, the chimney graft technique was used to debranch the brachiocephalic artery. Hemodynamics was stabilized postsurgically. Plain CT performed 20 days postoperatively confirmed that the intrathoracic hematoma had decreased in size. Although respiratory failure was persistent, there were improvements and the patient was extubated 34 days postoperatively and discharged from the intensive care unit 37 days postoperatively. On postoperative day 75, he was discharged from the hospital to an elder care facility. Few reports have focused on stent grafting for treating aortic arch aneurysm rupture. TEVAR using the chimney graft technique could be an effective treatment option for patients with a decreased ability to tolerate surgery.

Development of Delirium in the Intensive Care Unit in Patients after Endovascular Aortic Repair: A Retrospective Evaluation of the Prevalence and Risk Factors

Delirium is an acute form of nervous system dysfunction often observed in patients in the intensive care unit. Endovascular aortic repair (EVAR) is considered a minimally invasive surgical treatment for abdominal aortic aneurysm. Although the operation method is widely used, there are few investigations of the rate and risk factors of delirium development after the operation. In this study, we retrospectively examined the rate of delirium development in the intensive care unit (ICU) after EVAR, as well as the associated preoperative risk factors and effects on the lengths of ICU and hospital stays. We examined the 81 consecutive patients who underwent elective EVAR between November 2013 and August 2014. The Intensive Care Delirium Screening Checklist was used to diagnose delirium. Twenty patients (24.7%) were diagnosed with delirium in this study. The ICU and hospital length of stays of patients with delirium were 3.3 ± 2.4 days and 14.5 ± 11.9 days, respectively, the latter of which was significantly longer than that of patients without delirium (p = 0.019). Additionally, renal dysfunction, preoperative benzodiazepine use, and intraoperative transfusion were found to be risk factors for the development of delirium after elective EVAR.

Pericardial fat flap for mycotic aneurysm of the thoracic aorta

Standard treatment for mycotic aneurysm of thoracic aorta is complete debridement with replacement of the aneurysm with a homograft or Dacron graft. However, contamination from surrounding tissues may occur after the graft replacement. Transposition of the viable, well-vascularized tissues should be used to fill surrounding dead space and isolate the graft to prevent reinfection. Although the omentum is regarded as the best tissue, it is not always available for use. We describe here a new alternative technique for such situations, that is, the use of a pericardial fat flap for patients with a mycotic descending thoracic aortic aneurysm.

Pseudoaneurysm of the Anterior Tibial Artery following Ankle Arthroscopy in a Soccer Player

Ankle arthroscopy carries a lower risk of vascular complications when standard anterolateral and anteromedial portals are used. However, the thickness of the fat pad at the anterior ankle affords little protection for the thin-walled anterior tibial artery, rendering it susceptible to indirect damage during procedures performed on the anterior ankle joint. To our knowledge, only 11 cases of pseudoaneurysm involving the anterior tibial artery after ankle arthroscopy have been described in the literature. Here we reported a rare case of a 19-year-old soccer player who presented with pseudoaneurysm of the anterior tibial artery following ankle arthroscopy using an ankle distraction method and underwent anastomosis for the anterior tibial artery injury. Excessive distraction of the ankle puts the neurovascular structures at greater risk for iatrogenic injury of the anterior tibial artery during ankle arthroscopy. Surgeons should look carefully for postoperative ankle swelling and pain after ankle arthroscopy.

Thoracic endovascular aortic repair of a severely angulated aorta using a double-wire technique.

When endovascular treatment is performed, angulation of the access route for a device can make the operative procedure difficult. We encountered a case in which we successfully completed thoracic endovascular aortic repair (TEVAR) in a patient with severely angulated aorta by applying ‘double-wire technique’. The patient was an 80-year-old woman. An aneurysm with a 71-mm diameter was observed in the descending aorta. We performed TEVAR. Device delivery could not be achieved by a conventional procedure using one guide wire since the peripheral aorta was severely angulated. Therefore, in addition to a guide wire for main body, a stiff wire and a stiff sheath were introduced to straighten the angulation. The device was successfully introduced and TEVAR was completed. We used the Relay Plus® that facilitates tracking through the angulation. The device has a dual structure consisting of a hard sheath and a flexible sheath. We performed TEVAR successfully.

Treatment with Aortic Stent Graft Placement for Stanford B-Type Aortic Dissection in a Patient with an Aberrant Right Subclavian Artery

A 71-year-old man visited our hospital with the chief complaint of back pain and was diagnosed with acute aortic dissection (Debakey type III, Stanford type B). He was found to have a variant branching pattern in which the right subclavian artery was the fourth branch of the aorta. We performed conservative management for uncomplicated Stanford type B aortic dissection, and the patient was discharged. An ulcer-like projection (ULP) was discovered during outpatient follow-up. Complicated type B aortic dissection was suspected, and we performed thoracic endovascular aortic repair (TEVAR). The aim of operative treatment was ULP closure; thus we placed two stent grafts in the descending aorta from the distal portion of the right subclavian artery. The patient was released without complications on postoperative day 5. Deliberate sizing and examination of placement location were necessary when placing the stent graft, but operative techniques allowed the procedure to be safely completed.

The ratio of contrast medium volume to estimated glomerular filtration rate as a predictor of contrast‐induced nephropathy after endovascular aortic repair

OBJECTIVE This study aimed to determine the perioperative predictors of contrast medium-induced nephropathy (CIN) after endovascular aortic repair (EVAR). MATERIALS AND METHODS The data of 203 consecutive patients who underwent elective EVAR for thoracic and abdominal aortic aneurysm between January 2014 and September 2014 were retrospectively analyzed. CIN was defined according to the diagnostic criteria of the European Society of Urogenital Radiology. RESULTS Fourteen patients (6.9%) developed CIN after EVAR. Contrast medium volume (CV), preoperative serum creatinine, estimated glomerular filtration rate (eGFR), and the CV/eGFR ratio were significantly related with CIN development after EVAR. The CV/eGFR ratio was significantly higher in patients with CIN than those without CIN. Receiver operator characteristic curve analysis showed that the area under the curve of the CV/eGFR ratio was 0.782, indicating that it was the most important predictor. The appropriate CV/eGFR ratio cutoff was 1.62. Sensitivity and specificity were 85.7% and 65.6%, respectively. CONCLUSIONS The CV/eGFR ratio was a useful predictor of contrast medium-induced nephropathy after EVAR. It is possible that the score can be used in patients when managing the EVAR techniques and contrast medium volume. J. Med. Invest. 65:116-121, February, 2018.

A case of chronic left main trunk occlusion treated with off-pump coronary artery bypass grafting

Abstract Ischemic heart disease presents with various symptoms, and chest pain is a chief complaint. Occlusion of the left main trunk often results in serious symptoms such as cardiogenic shock. However, while extremely rare, left main trunk occlusion can present with only slight chronic symptoms. In the present case, a 62-year-old woman with few risk factors for ischemic heart disease visited our hospital complaining of exertional chest pain, which had gradually intensified over the past several years. Coronary artery computed tomography revealed total occlusion of the left main trunk, which was examined closely using coronary angiography. Coronary angiography showed that the left coronary artery was perfused by collateral pathways from the right coronary artery. The patient was thus diagnosed with chronic occlusion of the left main trunk. She underwent off-pump coronary artery bypass grafting, which proved to be an effective treatment.

Thoracic Endovascular Aortic Repair for Blunt Thoracic Aortic Injury: A Report of Three Cases in Which Surgeries Were Performed at Different Timings

Introduction Blunt thoracic aortic injury (BTAI) is a critical condition. Thoracic endovascular aortic repair (TEVAR) is considered a surgical treatment for BTAI. Reports reveal that some patients benefit from conservative and delayed operation rather than emergency operative therapy. Here, we present three BTAI cases that were treated with TEVAR using different timings. Case Presentation Case 1 involved a 49-year-old man injured in a car accident and who went into shock. After stabilization with Advanced Trauma Life Support in the emergency room, TEVAR was performed immediately. Case 2 involved a 69-year-old man who was injured after falling. His hemodynamic status was stable and enhanced computed tomography revealed intraluminal hematoma. He underwent TEVAR 15 days after the injury occurred, following conservative therapy. Case 3 involved a 60-year-old man who was injured in a car accident and presented BTAI with subarachnoid hemorrhage and diaphragm tear. A pseudoaneurysm was observed in the distal aortic arch. After open abdominal exploration, diaphragm repair, and observation for subarachnoid hemorrhage, TEVAR was performed 8 hours after arrival. All three patients survived. Conclusions We treated BTAI successfully. We suggest that TEVAR is useful for BTAI. The timing of the operation and therapeutic option, including conservative therapy, should be decided for each patient.