Yifei Pei

Endovascular Repair of Ascending Aortic Dissection : A Novel Treatment Option for Patients Judged Unfit for Direct Surgical Repair

OBJECTIVES This paper sought to report the outcomes of patients who are considered unfit for urgent surgical repair of ascending aortic dissections (AADs) who were treated using a novel endovascular repair strategy. BACKGROUND AAD is best treated by direct surgical repair. Patients who are unable to undergo this form of treatment have poor prognoses. Previously, clinical case reports related to endovascular repair of AAD have been controversial. METHODS Between May 2009 and January 2011, 41 consecutive patients with AAD were treated in our institution. Fifteen patients were considered poor candidates for direct surgical repair and subsequently underwent the endovascular repair. RESULTS The nature of the referral process to our tertiary care facility made the median time from aortic dissection onset to treatment 25.5 days (range: 6 to 353 days). Dissections in 5 patients (33.3%) were considered acute, and those in 10 patients (66.7%) were considered chronic. The rate of successful stent-graft deployment was 100%, and there were no major morbidities or deaths in the perioperative period. Median follow-up was 26 months (range: 16 to 35 months). One new dissection occurred in the aortic arch at 3 months and was treated with a branched endograft. Significant enlargements of true lumens and decreases of false lumens and overall thoracic aorta were noted after the procedures. CONCLUSIONS Endovascular repair of AAD was an appropriate treatment option in patients who were considered poor candidates for traditional direct surgical repair by the clinical criteria used in our institution. A larger series of cases with longer follow-up is needed to substantiate these results.

Overexpression of interleukin-1β and interferon-γ in type I thoracic aortic dissections and ascending thoracic aortic aneurysms: possible correlation with matrix metalloproteinase-9 expression and apoptosis of aortic media cells

OBJECTIVE To examine the expression of interleukin-1β and interferon-γ and their possible roles in aortic dissections and aneurysms. METHODS Aortic specimens were obtained from patients with type I thoracic aortic dissection, ascending thoracic aortic aneurysms, and control organ donors. The expression of interleukin-1β, interferon-γ, matrix metalloproteinase-9, and signal transduction factors phospho-p38 and phosphorylated c-jun N-terminal kinase (phospho-JNK) were detected by real time reverse transcription-polymerase chain reaction (real time RT-PCR), Western blot, and immunohistochemistry, respectively. Terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) staining was performed to detect apoptosis of media cells. The correlation of these factors and apoptosis was also studied. RESULTS Apoptosis in the media of thoracic aortic dissection and in ascending thoracic aortic aneurysms was dramatically higher than in the control group. The expression of interleukin-1β gradually increased from the control group, thoracic aortic dissection to ascending thoracic aortic aneurysms (p < 0.01, respectively). The expression of interferon-γ and matrix metalloproteinase-9 was significantly increased in the media of thoracic aortic dissection and ascending thoracic aortic aneurysms compared with the control group (p < 0.01, respectively). There were positive correlations between interleukin-1β versus matrix metalloproteinase-9, interleukin-1β versus phospho-p38 in thoracic aortic dissection (p < 0.01, respectively), and interferon-γ versus matrix metalloproteinase-9, interferon-γ versus phospho-JNK, interferon-γ versus apoptosis, and interleukin-1β versus apoptosis in ascending thoracic aortic aneurysms (p = 0.02, 0.02, p < 0.01, p < 0.01). CONCLUSIONS Interleukin-1β and interferon-γ might effect the formation of thoracic aortic dissection and ascending thoracic aortic aneurysms possibly through the up-regulation of matrix metalloproteinase-9 and the apoptosis of media cells in humans.

Treatment of type I endoleak after endovascular repair of infrarenal abdominal aortic aneurysm: success of fibrin glue sac embolization.

Purpose: To analyze a single-center experience of fibrin glue sac embolization to eliminate type I endoleaks after endovascular aneurysm repair (EVAR), assessing the feasibility and effectiveness of the technique in long-term follow-up. Methods: A retrospective study was conducted involving 783 EVAR patients treated between August 2002 and February 2009. Under a standardized protocol, 42 (5.4%) patients (37 men; mean age 73±8 years) underwent intraoperative transcatheter fibrin glue sac embolization to resolve type I endoleak persisting after initial intraoperative maneuvers to close the leak or in necks too short or angulated for cuff placement. Intrasac pressure was measured before and after glue injection. Computed tomographic angiography was performed to assess the outcome after 3, 6, and 12 months and annually thereafter. Results: In this type I endoleak cohort, 16 (38.1%) patients had proximal necks <10 mm long, and 5 (11.9%) patients had proximal neck angulation >60°; 22 additional devices (8 stents, 14 cuffs) had been placed in the initial attempts to resolve the endoleaks. After fibrin glue injection, 41 (97.6%) of the 42 endoleaks were resolved using a mean 15±10 mL of glue. Intrasac pressure decreased significantly in successfully treated cases. The patient who failed embolotherapy was converted to open surgery (2.4%); he died 2 months later from multiorgan failure. Two (4.8%) patients died in the perioperative period from myocardial infarction. One (2.4%) patient developed right lower extremity ischemia unrelated to the fibrin glue treatment. There were no allergic reactions. Over a median follow-up of 39.9 months (range 10–88), 3 (7.1%) patients died (1 aneurysm-related). Cumulative survival was 90.5% at 1 year, 87.0% at 3 years, and 82.6% at 5years. The mean maximal aneurysm diameter fell from the baseline 59.5±14.7 mm to 49.0±11.6 mm (p<0.001). Of the 4 patients with increased aneurysm diameter during follow-up, 1 was converted, 2 are being observed due to advanced age, and 1 died of renal failure. No recurrent type I endoleak or glue-related complications were observed in follow-up. Conclusion: Fibrin glue sac embolization to eliminate type I endoleak after EVAR yielded excellent results in our experience, effectively and durably resolving the leaks. Balloon occlusion of the proximal aorta must be done during glue injection to block proximal flow and facilitate formation of a structured fibrin clot.

Endovascular Repair of a Distal Aortic Arch Pseudoaneurysm with Use of a Scallop-edged Stent-graft

tomography showed marked accumulation of [ 18 F]fluorodeoxyglucose in the consolidation. The consolidation was deemed to be a local progression and CT-guided cutting needle biopsy was performed. The biopsy specimens mainly consisted of necrotic tissue in which there were a number of Aspergillus hyphae (Fig, d); no viable cancer tissue was found. The value of serum -D-glucan was normal (6.0 pg/mL; normal range, 11.0 pg/mL); serum Aspergillus antigen was negative. Since then, the patient has been receiving voriconazole (Vfend; Pfizer, New York, New York). Positron emission tomography performed at the latest follow-up (5 months after the initiation of the therapy for aspergilloma) revealed shrinkage of consolidation and decreased accumulation of [ 18 F]fluorodeoxyglucose. Okuma et al (3) reported cavity formation at a frequency of 14% (14 of 100 sessions) at an average of 1.5 months after RF ablation for lung cancer. Cavitation occurred more frequently in patients who had a lesion near the chest wall, lung cancers as the primary lesion, and pulmonary emphysema (3). In our case, a large cavity was formed after a total of three RF ablation sessions carried out for metastasis near the chest wall from primary lung cancer. Pulmonary aspergilloma is an Aspergillus infection that occurs in patients with preexisting cystic or cavitary lung disease. Residual cavities after tuberculosis are most commonly infected with Aspergillus species (4). Other conditions predisposing to aspergilloma include sarcoidosis, bronchiectasis, and pulmonary fibrosis (4). The present case suggests that a cavity formed after RF ablation for lung cancer may also be a scaffold for aspergilloma. Therefore, the possibility of aspergilloma should be considered in the case of consolidation formed in a cavity after RF ablation, and it should be differentiated from local tumor progression.

Total Endovascular Repair of Thoracoabdominal Aortic Aneurysms With Non-Customized Stent Grafts

BACKGROUND Total endovascular repair of thoracoabdominal aortic aneurysms with customized branched or fenestrated endografts could be technically challenging outside large-volume centers. This study aims to describe a new endovascular strategy for use of both noncustomized stent grafts and flow-diverting stents in treating complicated thoracoabdominal aortic aneurysms. METHODS Patients diagnosed with thoracoabdominal aortic aneurysms and deemed unfit for open surgical repair were recruited. The aim of the procedure was to cover the renovisceral segment of the aorta with flow-diverting uncovered stents, while covering the remaining aneurysm with stent grafts. Aneurysm morphologic evolution and the patency of the visceral branches were assessed at follow-up. RESULTS Between February 2012 and August 2013, 6 selective patients (4 men, mean age 58 years) underwent the novel joint procedure. During mean follow-up of 14 months, aneurysm shrinkage (maximum diameter decrease ＞5 mm) was demonstrated in 4 patients and aneurysm stabilization (maximum diameter decrease ＜5 mm) was observed in 2 patients. No aneurysm expansion was observed in any participants. Mean aneurysm diameter decreased from 65.0±8.8 mm to 58.5±12.2 mm (p=0.054), with a significant increase in average sac thrombus deposition volume (sac thrombosis ratio increased from 23.3%±7.4% to 98.0%±3.3%, p＜0.001). The majority of side branches (23 of 24) were successfully preserved. CONCLUSIONS Complete endovascular repair of thoracoabdominal aortic aneurysms with this novel joint procedure may be a feasible alternative in high surgical risk patients. Further validation of this technique is required to substantiate these results.

Dramatic Decrease of Aortic Longitudinal Elastic Strength in a Rat Model of Aortic Dissection

BACKGROUND This study aimed to evaluate thoracic aortic longitudinal elastic strength in a rat model of aortic dissection (AD). METHODS Young Sprague Dawley rats were fed 0.25% β-aminopropionitrile (BAPN). Biomechanical and biochemistry properties of the aorta were analyzed. Elasticity modulus, maximum stretching length, draw ratio, maximum load, maximum strength, and maximum extensibility were measured. RESULTS More than one-half of BAPN-treated rats (52.9%) died of aortic rupture secondary to AD during the experiment. The diameter of the aneurysms was 6.33 ± 1.17 mm and the length was 9.33 ± 4.95 mm. The maximum diameter was significantly increased in BAPN-treated rats with AD (group B2) compared with rats without AD (group B1) and control group (group A) (P = 0.001 and P < 0.001, respectively), but was not different between group B1 and group A (P = 0.108). Thickness of media and initial area in aorta of BAPN-treated rats were significantly increased compared with control group (P = 0.001 and P < 0.001, respectively), but no difference in initial area was observed between group B1 and group B2 (P = 0.54). Maximum stretching length, draw ratio, maximum load, maximum strength, maximum extensibility, and elasticity modulus were dramatically decreased in group B2 compared with group B1 and group A (group B2 vs. group B1: P < 0.001; group B1 vs. group A: P < 0.001). CONCLUSIONS We successfully established a rat model of AD with a high incidence of rupture and mortality. Examinations of strain and stress parameters as well as elasticity modulus of the dissected and the nondissected aorta help understand pathogenesis of AD.

Temporary Balloon Occlusion of Both the Superior Vena Cava and the Internal Jugular Vein to Achieve Removal of a Migrated Foreign Body

A 34-year-old man had a 1.1cm flying metallic fragment embedded in a wound in his neck, which migrated over a period of time to lodge finally inside his right internal jugular vein. Angioplasty balloons were placed in the internal jugular vein and the superior vena cava to keep the fragment from moving with the blood flow during surgery. The fragment was then removed with forceps and the incision closed.

Comparison of open surgery and endovascular procedures as a therapeutic choice for visceral artery aneurysms

Objectives Visceral arterial aneurysms may be treated using open surgery or endovascular repair, but the best approach remains controversial. This was a retrospective study aiming to compare open surgery and endovascular treatment strategies for visceral arterial aneurysms. Methods The study included all 93 patients who were admitted with visceral artery aneurysms between January 2001 and January 2011 at the Department of Vascular Surgery, Changhai Hospital, Shanghai, China. All cases underwent either open or endovascular procedures. Overall survival and adverse events were compared between the groups. Success rate, blood loss, length of surgery, and length of hospital stay were also compared. The patients were followed up at three, six, and 12 months then every year until April 2014. Results Open surgery was performed on 34 patients and endovascular procedures on 59. There were no differences in characteristics of the patients between the open surgery and endovascular groups. The perioperative complication rate was 52.9 and 13.6% in the open surgery and endovascular groups, respectively. Mean follow-up was 36.8 months (range: 11 months to 10 years). The one- and five-year survival rates were 100 and 60.6%, respectively, in the open surgery group, compared to 100 and 84.5% in the endovascular group. Multivariate analysis for factors related to overall survival showed that there was a significant relationship with the treatment approach (HR = 0.479, 95%CI: 0.278–0.825; P = 0.008) and the presence of false aneurysm (HR = 2.929, 95%CI: 1.388–6.180, P = 0.005). Conclusions Endovascular repair could be considered as an effective method for visceral artery aneurysm. Endovascular repair showed lower perioperative complication rates and better long-term survival.