Utility of radiologic review for noncardiac findings on multislice computed tomography in patients with severe aortic stenosis evaluated for transcatheter aortic valve implantation

Achieving Hemostasis Posttranscatheter Aortic Valve Replacement in a Patient with Aortobifemoral Bypass Graft Using Perclose Device: A Novel Technique

The presence of aortobifemoral bypass graft can complicate vascular access during percutaneous intervention. Choosing an access route for transcatheter aortic valve replacement (TAVR) in this patient population can be challenging. Access options are further limited by the presence of coexisting vascular comorbidities such as extensive peripheral artery diseases in these patients. Adequate preoperative planning to determine the suitability of different access sites is, therefore, very crucial. Our case report shows that the use of Perclose can be a viable option for achieving hemostasis after a direct puncture of an aortobifemoral bypass graft during transfemoral TAVR.

Incidental findings on computed tomography for preoperative assessment before transcatheter aortic valve implantation in Japanese patients

Extra-cardiovascular incidental findings (IFs) on preoperative computed tomography (CT) are frequently observed in transcatheter aortic valve implantation (TAVI) candidates. However, the backgrounds of TAVI candidates and comorbidities differ based on the race and/or country, and data on IFs in a specific population are not always applicable to another. The aim of this study was to assess the prevalence, type, and clinical impact of IFs in Japanese TAVI candidates. This was a retrospective, single-center, observational study. CT reports of 257 TAVI candidates were reviewed, and IFs were classified as (a) insignificant: findings that did not require further investigation, treatment, or follow-up; (b) intermediate: findings that needed to be followed up or were considered for further investigation but did not affect the planning of TAVI; and (c) significant: findings that required further investigation immediately or affected the planning of TAVI. At least one IF was found in 254 patients (98.8%). Insignificant, intermediate, and significant IFs were found in 253 (98.4%), 153 (59.5%), and 34 (13.2%) patients, respectively. Newly indicated significant IFs were found in 19 patients (7.4%). In 2 patients (0.8%), TAVI was canceled because of significant IFs. In patients who consequently underwent TAVI, the presence of significant IFs was not associated with the duration from CT performance to TAVI [28 (19-40) days vs. 27 (19-43) days, p = 0.74] and all-cause mortality during the median follow-up period of 413 (223-805) days (p = 0.44). Almost all Japanese TAVI candidates had at least one IF, and the prevalence of significant IFs was not negligible. Although the presence of significant IFs was not associated with mid-term mortality, appropriate management of IFs was considered important.

Incidental abnormal CT scan findings during transcatheter aortic valve implantation assessment: incidence and implications

Objectives

The aim of this retrospective series is to describe the prevalence and clinical significance of the incidental findings found during pre–transcatheter aortic valve implantation (TAVI) work-up and to ascertain the clinical course of such patients.

Methods

Consecutive patients undergoing TAVI from 2013 to 2015 where a TAVI CT assessment was performed (n=138) were included in the study. All incidental findings that were not expected from the patient’s history were discussed at the TAVI multidisciplinary meeting in order to ascertain the clinical significance of said findings and whether they would alter the proposed course of treatment. Mortality data were determined by careful retrospective case note and follow-up appointment analysis.

Results

Seventy-eight patients (57%) were found to have incidental findings on pre-TAVI CT scan. The majority of patients had benign pathology with high incidence in particular of diverticular disease, pleural effusions, gallstones, hiatus hernia and degenerative spinal disease. Vascular pathology such as superior mesenteric, renal and iliac artery stenoses and abdominal aortic aneurysm was detected in seven patients. In terms of long-term mortality data, we found no significant difference between those with incidental findings and those without (p=0.48). Survival as assessed by Kaplan-Meier analysis showed no significant difference between those with and without incidental abnormal CT scan findings (p=0.98).

Conclusions

Incidental findings with potential for malignancy are common in an elderly, comorbid population. Ultimately, clinical correlation and prognosis must be swiftly ascertained in order to streamline the patients down the appropriate management pathway while avoiding unnecessary delay for treatment of their aortic stenosis.

Multidetector computed tomography evaluation of candidates for transcatheter aortic valve implantation

In transcatheter aortic valve implantation (TAVI), a biologic valve mounted in a stent is implanted without removing the native valve. This procedure was first done in humans by Alain Cribier in 2002 and was included in clinical guidelines after the multicenter PARTNER (Placement of AoRtic TraNscathetER) randomized clinical trial, which showed that TAVI obtained better outcomes than conservative medical treatment and is an alternative to surgery in patients with high surgical risk. Candidates for TAVI must be assessed to determine whether the procedure is feasible, because TAVI is not ideal for all patients who are considered inoperable. Multidetector computed tomography plays an important role in the anatomic evaluation of candidates and in guiding the procedure in those who are finally selected.

Thoracic Incidental Findings in Preoperative Computed Tomography Evaluation for Transcatheter Aortic Valve Implantation (TAVI)

BACKGROUND

Many older patients with aortic stenosis are excluded from surgical intervention due to multiple comorbidities. For these patients, transcatheter aortic valve implantation (TAVI) is a viable treatment alternative. Cardiothoracic computed tomography (CT) provides detailed anatomic assessment of the aortic root structures for patient selection, preprocedural planning, and intraoperative decision-making; however, nonaortic incidental findings are frequently detected. The prevalence and clinical significance of these findings have not been well described.

MATERIALS AND METHODS

This retrospective study examined incidental findings in 209 consecutive patients (96 women and 113 men; mean age, 70 y) with aortic stenosis undergoing preoperative cardiothoracic CT evaluation for TAVI during a 3-year period. Incidental findings were recorded, and medical records were reviewed for follow-up diagnostic examinations.

RESULTS

Incidental findings, both significant and nonsignificant, were observed in 85.6% of patients (179/209). Noncalcified pulmonary nodules were the most common incidental finding occurring in 59/209 (28.2%) patients, followed by pleural effusion and emphysema both of which occurred in 34/209 (16.3%) patients, respectively.

CONCLUSIONS

Cardiothoracic CT obtained for evaluation before TAVI has a high frequency of incidental findings.

Multidimensional MDCT angiography in the context of transcatheter aortic valve implantation

OBJECTIVE

Transcatheter aortic valve implantation has emerged as a viable treatment alternative for patients with severe aortic stenosis who are not surgical candidates. Multidimensional (3D and 4D) MDCT angiography plays a critical role in the safety, success, and outcome of an institutional transcatheter aortic valve implantation program.

CONCLUSION

Given the increasing therapeutic role of this innovative technique, an understanding of essential imaging concepts in its context is critical for appropriate image acquisition and interpretation.

Imaging Pandora's Box: incidental findings in elderly patients evaluated for transcatheter aortic valve replacement

OBJECTIVE

To determine the frequency and clinical impact of noncardiovascular incidental findings (IFs) detected on preoperative computed tomographic angiography (CTA) of the chest/abdomen/pelvis performed in elderly patients with severe aortic stenosis being considered for transcatheter aortic valve replacement (TAVR).

PATIENTS AND METHODS

The CTA studies for 424 consecutive patients being evaluated for TAVR between January 1, 2009, through January 24, 2012, were reviewed for noncardiovascular IFs (62.0% male; median ± SD age, 82 ± 8.3 years). The electronic medical record was reviewed to assess for subsequent clinical management and survival.

RESULTS

Potentially pathologic IFs (PPIFs) were present in 285 patients (67.2%). The mean ± SD number of PPIFs per patient was 1.1 ± 1.0 (range, 0-4). Factors associated with higher numbers of PPIFs were reduced ejection fraction (P=.02) and history of smoking (P=.06). Potentially pathologic incidental findings prompted clinical work-up in 39 patients (9.2%) and delayed or canceled treatment plans for aortic stenosis in 7 patients (1.7%). The number needed to image to diagnose a new malignancy or medical condition was 19. The number of PPIFs was predictive of poor overall survival before (hazard ratio, 1.58; 95% CI, 1.31-1.88) and after (hazard ratio, 1.45; 95% CI, 1.19-1.76) adjustment for baseline clinical variables (P<.001 for both).

CONCLUSION

This investigation found that PPIFs are common in elderly patients undergoing TAVR-CTA scans and, once discovered, commonly generate further clinical evaluation. Higher numbers of PPIFs may be predictive of poorer survival, but further study is required to guide the appropriateness of pursuing diagnostic evaluations for asymptomatic PPIFs in this elderly population.

Transfemoral Edwards SAPIEN aortic valve implantation through aortofemoral endograft

We present the case of an 86-year-old woman with an aortobifemoral endograft and porcelain aorta who underwent transfemoral transcatheter aortic valve implantation (TAVI). A femoral cutdown was performed to the left limb of the endograft, and the needle puncture into the graft required sequential incisions and dilation to allow access of the 18F Edwards SAPIEN expandable eSheath (Edwards Lifesciences, Irvine, CA). A 26-mm Edwards SAPIEN transcatheter aortic valve was then successfully deployed. The cutdown was closed and hemostasis was achieved without any iatrogenic narrowing of the graft. Transfemoral TAVI through surgical cutdown with dilation of a femoral endograft is safe and feasible.

Incidental findings in computed tomographic angiography for planning percutaneous aortic valve replacement: advanced age, increased cancer prevalence?

BACKGROUND

Increased age is linked with a higher cancer risk according to model calculations. Patients with severe atherosclerotic aortic stenosis are of old age, therefore, a high incidence of malignancies should be found.

PURPOSE

To evaluate the prevalence of clinically significant and potentially malignant incidental findings at computed tomographic angiography (CTA) performed in patients with severe aortic stenosis being assessed as to their suitability for transcatheter aortic valve replacement (TAVR).

MATERIAL AND METHODS

Between August 2008 and April 2010, CTA of the thoraco-abdominal aorta and the pelvic arterial vessels was performed in 131 patients. There were 62 women (47%) and 69 men (53%); the mean age was 81.6 years (range, 64-91 years). Incidental findings were recorded and categorized as potentially malignant, clinically significant, and clinically insignificant. Clinically significant findings were defined as those requiring immediate therapy, intervention or imaging, or follow-up examination.

RESULTS

Of the 131 study patients, 31 (23.7%) presented significant extravascular incidental findings, 19 (14.5%) in the thorax, and 12 (9.2%) in the abdomen. Five lesions (3.8%) were considered potentially malignant, three of them (2.3%) were new and highly suspicious for malignancies (two renal cell carcinomas and one hepatocellular carcinoma). In two patients (1.5%) mediastinal lymphadenopathy was found (recurrent malignant lymphoma und new metastases from known bladder cancer).

CONCLUSION

The prevalence of highly suspicious malignant incidental findings in patients undergoing TAVR is 3.8% with an average age of 81.6 years which is not high compared to prevalence in the literature dealing with patients aged <70 years.

Radiation dose effect in locally advanced non-small cell lung cancer

Radiation is the foundation of treatment for locally advanced non-small cell lung cancer (NSCLC), and as such, optimal radiation dose is essential for successful treatment. This article will briefly review biological considerations of radiation dose and their effect in the context of three-dimensional conformal radiation therapy (3D-CRT) including intensity modulated radiation therapy (IMRT) and stereotactic body radiation therapy (SBRT) for NSCLC. It will focus on literature review and discussions regarding radiation dose effect in locally advanced NSCLC including potential severe and lethal toxicities of high dose radiation given with concurrent chemotherapy. Potential new approaches for delivering safe and effective doses by individualizing treatment based on functional imaging are being applied in studies such as the PET boost trial and RTOG1106. The RTOG concept of delivering high dose radiation to the more resistant tumors with the use of isotoxic dose prescription and adaptive planning will also be discussed in detail.

ACR appropriateness criteria imaging for transcatheter aortic valve replacement

Although aortic valve replacement is the definitive therapy for severe aortic stenosis, almost half of patients with severe aortic stenosis are unable to undergo conventional aortic valve replacement because of advanced age, comorbidities, or prohibitive surgical risk. Treatment options have been recently expanded with the introduction of catheter-based implantation of a bioprosthetic aortic valve, referred to as transcatheter aortic valve replacement. Because this procedure is characterized by lack of exposure of the operative field, image guidance plays a critical role in preprocedural planning. This guideline document evaluates several preintervention imaging examinations that focus on both imaging at the aortic valve plane and planning in the supravalvular aorta and iliofemoral system. The ACR Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every 2 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances in which evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.

CT and MR imaging of the aortic valve: radiologic-pathologic correlation

Valvular disease is estimated to account for as many as 20% of cardiac surgical procedures performed in the United States. It may be congenital in origin or secondary to another disease process. One congenital anomaly, bicuspid aortic valve, is associated with increased incidence of stenosis, regurgitation, endocarditis, and aneurysmal dilatation of the aorta. A bicuspid valve has two cusps instead of the normal three; resultant fusion or poor excursion of the valve leaflets may lead to aortic stenosis, the presence of which is signaled by dephasing jets on magnetic resonance (MR) images. Surgery is generally recommended for patients with severe stenosis who are symptomatic or who have significant ventricular dysfunction; transcatheter aortic valve implantation (TAVI) is an emerging therapeutic option for patients who are not eligible for surgical treatment. Computed tomography (CT) is an essential component of preoperative planning for TAVI; it is used to determine the aortic root dimensions, severity of peripheral vascular disease, and status of the coronary arteries. Aortic regurgitation, which is caused by incompetent closure of the aortic valve, likewise leads to the appearance of jets on MR images. The severity of regurgitation is graded on the basis of valvular morphologic parameters; qualitative assessment of dephasing jets at Doppler ultrasonography; or measurements of the regurgitant fraction, volume, and orifice area. Mild regurgitation is managed conservatively, whereas severe or symptomatic regurgitation usually leads to valve replacement surgery, especially in the presence of substantial left ventricular enlargement or dysfunction. Bacterial endocarditis, although less common than aortic stenosis and regurgitation, is associated with substantial morbidity and mortality. Electrocardiographically gated CT reliably demonstrates infectious vegetations and benign excrescences of 1 cm or more on the valve surface, allowing the assessment of any embolic complications.

Multimodality imaging throughout transcatheter aortic valve implantation

Transcatheter aortic valve implantation (TAVI) is a novel, less-invasive technique used to treat selected patients with severe aortic valve stenosis with a high surgical risk. Noninvasive imaging before, during and after the procedure is of the utmost importance in this minimally invasive procedure. Screening of the patient and sizing of the aortic root by echocardiography and multislice computed tomography is of great importance to ensure success of the TAVI procedure. Echocardiography and fluoroscopy are essential during the procedure. During follow-up of the patients, echocardiography is important to evaluate the prosthesis function, durability and integrity. Additionally, multislice computed tomography and MRI might be helpful in the follow-up of selected cases. This article outlines the evolving role of multimodality imaging throughout TAVI in patients with severe aortic valve stenosis. It describes, in a stepwise approach, how multimodality imaging by echocardiography, angiography, multislice computed tomography and MRI enhances the TAVI procedure.