Abdominal aortic aneurysm (AAA) is abnormal dilatation of the aorta, carrying a substantial risk of rupture and thereby marked risk of death. Open repair of AAA involves lengthy surgery time, anesthesia, and substantial recovery time. Endovascular aneurysm repair (EVAR) provides a safer option for patients with advanced age and pulmonary, cardiac, and renal dysfunction. Successful endovascular repair of AAA depends on correct selection of patients (on the basis of their vascular anatomy), choice of the correct endoprosthesis, and familiarity with the technique and procedure-specific complications. The type of aneurysm is defined by its location with respect to the renal arteries, whether it is a true or false aneurysm, and whether the common iliac arteries are involved. Vascular anatomy can be divided more technically into aortic neck, aortic aneurysm, pelvic perfusion, and iliac morphology, with grades of difficulty with respect to EVAR, aortic neck morphology being the most common factor to affect EVAR appropriateness. When choosing among the devices available on the market, one must consider the patient's vascular anatomy and choose between devices that provide suprarenal fixation versus those that provide infrarenal fixation. A successful technique can be divided into preprocedural imaging, ancillary procedures before AAA stent-graft placement, the procedure itself, postprocedural medical therapy, and postprocedural imaging surveillance. Imaging surveillance is important in assessing complications such as limb thrombosis, endoleaks, graft migration, enlargement of the aneurysm sac, and rupture. Last, one must consider the issue of radiation safety with regard to EVAR.

Elective abdominal aortic aneurysm (AAA) repair is recommended for aneurysms greater than 5.5 cm, symptomatic, or rapidly expanding more than 0.5 cm in 6 months. Seventy-five percent of AAAs today are treated with endovascular aneurysm repair (EVAR) rather than open repair. This is fostered by the lower periprocedural mortality, complications, and length of hospital stay associated with EVAR. However, some studies have demonstrated EVAR to result in higher reintervention rates than with open repair, largely due to endoleaks. Type II is the most common, making up 10-25% of all endoleaks. Type II endoleaks, can potentially enlarge and pressurize the aneurysm sac with a risk of rupture. However, many type II endoleaks spontaneously resolve or never lead to sac enlargement. Imaging surveillance and approaches to management of type II endoleaks are reviewed here.

Pulmonary embolus (PE) is the third most common cause of cardiovascular death with more than 600,000 cases occurring in the USA per year. About 45% of patients with acute PE will have acute right ventricular failure, and up to 3.8% of patients will develop chronic thromboembolic pulmonary hypertension (CTEPH) with progressive, severe, chronic heart failure. The right ventricle (RV) is constructed to accommodate a low-resistance afterload. Increases in afterload from acute massive and submassive PE and CTEPH may markedly compromise the RV function leading to hemodynamic collapse and death. The purpose of this educational manuscript is to instruct on the pathophysiology of RV failure in massive and submassive PE and CTEPH. It is important to understand the pathophysiology of these diseases as it provides the rationale for therapeutic intervention by the Interventional Radiologist. We review here the pathophysiology of right ventricular (RV) failure in acute massive and submassive PE and CTEPH.

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VASCULAR AND INTERVENTIONAL RADIOLOGY Percutaneous image-guided needle biopsy of the lung is a well-established and accurate method used to diagnose pulmonary lesions with 93%-95% diagnostic accuracy (1-3). The demand for lung biopsy is increasing, given the increasing rates of lung cancer, the higher detection rate of asymptomatic lung nodules, and the demand for tissue for new molecular profiling and genomic analysis (4).The most common complication of percutaneous lung biopsy is pneumothorax. Most series report incidences of 20%-25% for pneumothorax and 4%-8% for chest tube placement, although rates as high as 47% and 22%, respectively, have been reported (5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19). The economic burden of a complicated lung biopsy is substantial, with increased costs of 300%-400% (20,21). There is great interest in reducing the occurrence of iatrogenic pneumothorax, which should translate into a lower rate of chest tube placement and subsequent hospital admission.Pneumothorax is caused by air leaking out of the lung through the needle puncture site at the visceral pleura once the needle is removed (22,23). Several studies have shown that sealing the pleural puncture site with a variety of materials, including autologous blood, hydrogel plug, fibrin glue, gelatin sponge slurry or plug, or saline, reduces the risk of pneumothorax and chest tube placement (9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19). Two of the best-studied sealants are autologous blood patch injection (ABPI) and a manufactured hydrogel plug called BioSentry, which was formerly known as Bio-Seal (Surgical Specialties, Wyoming, Pa), with proven efficacy based on prospective randomized studies (13,14). ABPI uses the participant's own blood to seal the biopsy track. The hydrogel plug expands on contact with moisture and seals the biopsy track.We hypothesized that ABPI is noninferior to a hydrogel plug regarding the rate of iatrogenic pneumothorax in CT-guided needle biopsy of the lung. We conducted a prospective single-center randomized controlled trial to test this hypothesis.