Simple 2-dimensional anatomic model to predict the risk of coronary obstruction during transcatheter aortic valve replacement

OBJECTIVE

In this study, a 2-dimensional (2D) index relying on preprocedural computed tomography (CT) data was developed to evaluate the risk of coronary obstruction during transcatheter aortic valve replacement (TAVR) procedures.

METHODS

Anatomic measurements from pre-TAVR CT scans were collected in 28 patients among 600 who were flagged as high risk (defined as meeting coronary artery height, h, <14 mm and/or sinus of Valsalva diameter, SOVd, <30 mm) for coronary obstruction. A geometric model derived from these anatomic measurements was used to predict the post-TAVR native cusp apposition relative to the coronary ostium. The distance from the cusp to the coronary ostium, DLC2D, was measured from the geometric model and indexed with the coronary artery diameter, d, to yield a fractional obstruction measure, DLC2D/d.

RESULTS

Twenty-three of 28 high-risk patients successfully underwent TAVR without coronary obstruction, of whom 1 had coronary obstruction and 4 were deemed non-TAVR candidates. DLC2D/d differed significantly between the 2 groups (P < .0018), but neither h nor SOVd did (P > .32). The optimal sensitivity and specificity for DLC2D/d were 85% and occurred at a cutoff of 0.45. The optimal sensitivity and specificity of h and SOVd in this high-risk group were only 60% and 40%, respectively, for cutoffs of h = 10 mm and SOVd = 30.5 mm.

CONCLUSIONS

The 2D geometric model derived in this study shows promise for identifying patients with low-lying coronary ostium and/or small SOVd that may be safely treated with TAVR. DLC2D/d is more predictive of obstruction or poor TAVR candidacy compared with h and SOVd.

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.

Principles and applications of dual source CT

This article describes the technical principles and clinical applications of dual source CT. A dual source CT (DSCT) is a CT system with two x-ray tubes and two detectors at an angle of approximately 90°. Both measurement systems acquire CT scan data simultaneously at the same anatomical level of the patient (same z-position). DSCT provides temporal resolution of approximately a quarter of the gantry rotation time for cardiac, cardio-thoracic and pediatric imaging. Successful imaging of the heart and the coronary arteries at high and variable heart rates has been demonstrated. DSCT systems can be operated at twice the spiral pitch of single source CT systems (up to pitch 3.2). The resulting high table speed is beneficial for pediatric applications and fast CT angiographic scans, e. g. of the aorta or the extremities. Operating both X-ray tubes at different tube potential (kV) enables the acquisition of dual energy data and the corresponding applications such as monoenergetic imaging and computation of material maps. Spectral separation can be improved by different filtration of the X-ray beams of both X-ray tubes. As a downside, DSCT systems have to cope with some challenges, among them the limited size of the second measurement system, and cross-scattered radiation.

Modeling risk of coronary obstruction during transcatheter aortic valve replacement

OBJECTIVE

In this study we aimed to evaluate risk of coronary obstruction during transcatheter aortic valve replacement and develop improved criteria based on computational modeling.

METHODS

Patient specific 3-dimensional models were constructed and validated for 28 patients out of 600 patients who were flagged as high risk for coronary obstruction (defined as meeting coronary ostium height < 14 mm and/or sinus of Valsalva diameter [SOVd] < 30 mm). The models consisted finite element analysis to predict the post- transcatheter aortic valve replacement native cusp apposition relative to the coronary ostium and were validated in vitro. The distance from cusp to coronary ostium (DLC) was derived from the 3-dimensional models and indexed with the coronary artery diameter to yield a fractional obstruction measure (DLC/d).

RESULTS

Twenty-two out of 28 high-risk patients successfully underwent transcatheter aortic valve replacement without coronary obstruction and 6 did not. DLC/d between the 2 groups was significantly different (P < .00078), whereas neither coronary ostium height nor SOVd were significantly different (P > .32). A cutoff of DLC/d < 0.7 was predictive with 100% sensitivity and 95.7% specificity. The optimal sensitivity and specificity of coronary ostium height and SOVd in this high-risk group was only 60% and 40%, respectively, for cutoff coronary ostium height of 10 mm and SOVd of 30.5 mm.

CONCLUSIONS

Three-dimensional modeling has the potential to enable more patients to be safely treated with transcatheter aortic valve replacement who have a low-lying coronary ostium or small SOVd. DLC/d is more predictive of obstruction than coronary ostium height and SOVd.

Frequency and impact of incidental findings on computed tomography during work-up for transcatheter aortic valve implantation: single centre experience and review of the literature

OBJECTIVE

To assess the frequency and impact of incidental findings (IF) on CT during work-up for transcatheter aortic valve intervention (TAVI).

METHODS

A consecutive cohort of patients referred for consideration of TAVI who underwent a CT scan between 2009 and 2018 were studied retrospectively. CT reports were reviewed for the presence of IFs and categorised based upon their clinical significance: (a) insignificant-findings that did not require specific treatment or follow-up; (b) intermediate-findings that did not impact on the decision-making process but required follow-up; (c) significant-findings that either required urgent investigation or meant that TAVI was clinically inappropriate.

RESULTS

A total of 652 patients were included, whose median age was 82 years. One or more insignificant IF was found in 95.6% of patients. Intermediate IFs were documented in 5.4%. 91 (14%) patients had at least one significant IF. These included possible malignancy in 67 (74%). The ultimate decision to offer aortic valve intervention was only changed by the presence of an IF in 3.5% of cases.

CONCLUSION

Clinically significant IFs are detected in more than 1 in 10 of patients undergoing CT as part of a TAVI work-up, although just over half of these patients still receive aortic valve intervention.

ADVANCES IN KNOWLEDGE

This study is the largest UK cohort, which, when combined with a review of existing literature, provides a clear picture of the frequency and clinical impact of IFs found at CT for TAVI assessment.

Outcomes of incidental findings on multi-detector computed tomography for transcatheter aortic valve implantation assessment: A single-centre study and review of the literature

INTRODUCTION

Patients with severe aortic stenosis (AS) require multi-detector computed tomography (MDCT) when considered for transcatheter aortic valve implantation (TAVI). Incidental findings on MDCT are common given the age group and region imaged. Our aim was to evaluate the frequency and outcome of incidental findings (IF) identified on MDCT and the impact on survival.

METHODS

This single-centre analysis retrospectively reviewed severe AS patients who underwent MDCT during TAVI workup. MDCT reports were reviewed for any IF and defined into three categories: IF of no relevant clinical significance (IF-NoCS), IF of non-immediate clinical significance (IF-NICS) and IF of immediate clinical significance (IF-ICS). Demographics, follow-up of IF and survival were calculated from MDCT date.

RESULTS

Two hundred and sixty-five patients underwent MDCT for TAVI suitability (mean age 83 ± 6 years, 52% male). The majority proceeded to TAVI (65%). Renal lesions (25%) and lung nodules (18%) were the most common IF. Fifty-nine patients (22%) had IF-NICS; 39% (23/59) were benign, 59% were not further investigated and one patient had suspected lung cancer. Six patients (2.3%) had IF-ICS and all were diagnosed with lung cancer. During a median follow-up of 272 days, there was no survival difference between patients with IF-ICS or IF-NICS versus patients without IF or IF-NoCS in the overall cohort (P = 0.44) or in TAVI patients (P = 0.88).

CONCLUSION

Incidental findings on MDCT are common with one-quarter having IF-ICS or IF-NCIS. Most patients with IF-NICS did not undergo further investigation. Standardized reporting of MDCT may assist in clarifying the need for further investigation which will in turn influence decision and timing to proceed with TAVI.

The role of computed tomography in the planning of transcatheter aortic valve implantation: a retrospective analysis in 200 procedures

AIM

The aim of our study is to show the importance of multislice computed tomography (CT) assessment in the overall management and diagnostic framework of transcatheter aortic valve replacement (TAVI) procedure candidates.

METHODS

Between June 2015 and April 2017, 200 patients with severe aortic stenosis, not eligible for surgery, were enrolled, as defined by EuroSCORE; they were submitted to TAVI at the interventional cardiology department of the Tor Vergata Polyclinic. CT studies were performed using a 64-slice scanner.

RESULTS

The reports and datasets produced during the pre-TAVI CT evaluation were retrospectively evaluated.

DISCUSSION

In TAVI candidates, accurate aortic valve shape and dimensions evaluation is crucial for the proper deployment of the prosthetic valve and in order to reduce postprocedural complications. ECG retrospective gated cardiac CT gives the clinician three-dimensional images of the heart, with high spatial resolution and multiplanar reconstructions allowing accurate visualization of the aortic annulus and coronary ostia to be obtained, and the evaluation of arterial calcifications. Furthermore, CT can provide data on the suitability of peripheral vascular accesses. Moreover, this technique can point out the presence of clinically relevant extracardiac findings. Therefore, CT evaluation assures a safe, reliable and prognostically relevant method for TAVI preprocedural planning.

CONCLUSION

Our study remarks the importance of CT assessment in the overall management and diagnostic framework of TAVI candidates; the information provided is essential in order to minimize possible complications and to improve the quality of the therapeutic planning.

Incidental findings in multislice computed tomography prior to transcatheter aortic valve implantation: frequency, clinical relevance and outcome

Multislice computed tomography (MSCT) has emerged as the mainstay in patients planned for transcatheter aortic valve implantation (TAVI). Incidental findings (IF) in MSCT are common. However, the exact incidence, clinical relevance and further consequences of IF are unclear and it is controversial whether IF adversely affect patients' outcome. We analyzed MSCT data of 1050 patients screened for TAVI between January 2011 and December 2014. Median follow-up of patients was 20 months. In total, 3194 IF were identified, which were classified into clinically non-relevant IF (2872, 90%) and clinically relevant IF (322, 10%). In 25% of patients (258/1050) at least one clinically relevant IF was present. Age (80 ± 7 vs. 80 ± 7 years; p = 0.198) and EuroSCORE II (3.6% [2.1-5.7] vs. 3.6% [2.1-5.9]; p = 0.874) was similar between patients with and without a clinically relevant IF. TAVI was performed less frequently in patients with a clinically relevant IF (76% vs. 85%; p < 0.001), with more patients receiving surgical aortic valve replacement in that group (14% vs. 11%; p = 0.042), possibly due to the high rate of incidental aneurysms of the ascending aorta (n = 48). If TAVI was performed mortality did not differ (30-days: 4% vs. 3%; p = 0.339, 1-year: 11% vs. 14%; p = 0.226) between patients with and without a clinically relevant IF. Our study is the largest study to analyze prevalence, clinical relevance and therapeutic consequences of IF during screening for TAVI. IF in pre-procedural MSCT are common and clinically relevant in one-quarter of patients. However, these findings had no impact on overall mortality.

Impact of Potentially Malignant Incidental Findings by Computed Tomographic Angiography on Long-Term Survival After Transcatheter Aortic Valve Implantation

Computed tomography angiography (CTA) in workup for transcatheter aortic valve implantation (TAVI) frequently reveals potentially malignant incidental findings. Most incidental findings provoke discussions on their influence. We aimed to analyze if these findings were a predictor of long-term survival after TAVI. In a single-center retrospective analysis, all consecutive patients with pre-TAVI CTA were included (years 2009 to 2014). Patients were divided by presence or absence of incidental findings. We analyzed up to 5 years of all-cause, non-cardiovascular and cardiovascular mortality for all 553 patients who underwent TAVI; 113 had a potentially malignant incidental finding (20.4%). At 5 years, all-cause mortality risk was 64.5% in patients with versus 49.1% in patients without a finding (hazard ratio [HR] 1.70, 95% confidence interval [CI] 1.25 to 2.31). After adjustment, the findings remained an independent predictor of all-cause (adjusted HR 1.46, 95% CI 1.07 to 1.99) and non-cardiovascular mortality (adjusted subdistribution HR 1.84, 95% CI 1.06 to 3.20), but not of cardiovascular mortality. In conclusion, the presence of potentially malignant incidental findings on CTA is an independent predictor of long-term all-cause and noncardiovascular mortality but not of cardiovascular mortality.

[Clinically relevant incidental cardiovascular findings in CT examinations]

BACKGROUND AND METHOD

Incidental cardiovascular findings are a frequent phenomenon in computed tomography (CT) examinations. As the result of a dedicated PubMed search this article gives a systemic overview of the current literature on the most important incidental cardiovascular findings, their prevalence and clinical relevance.

RESULTS

The majority of incidental cardiovascular findings are of only low clinical relevance; however, highly relevant incidental findings, such as aortic aneurysms, thromboses and thromboembolic events can also occasionally be found, especially in oncology patients.

CONCLUSION

The scans from every CT examination should also be investigated for incidental findings as they can be of decisive importance for the further clinical management of patients, depending on their clinical relevance.

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.

Run-Off Computed Tomography Angiography (CTA) for Discriminating the Underlying Causes of Intermittent Claudication

AIM

To evaluate run-off computed tomography angiography (CTA) of abdominal aorta and lower extremities for detecting musculoskeletal pathologies and clinically relevant extravascular incidental findings in patients with intermittent claudication (IC) and suspected peripheral arterial disease (PAD). Does run-off CTA allow image-based therapeutic decision making by discriminating the causes of intermittent claudication in patients with suspected peripheral arterial disease PAD?

MATERIAL AND METHODS

Retrospective re-evaluation of CTAs performed in patients with acute or chronic intermittent claudication (i.e., Fontaine stages I to IIB) between January 2005 and October 2013. Allocation to one of three categories of underlying causes of IC symptoms: vascular, musculoskeletal (MSK) or both. Clinically relevant extravascular incidental findings were evaluated. Medical records were reviewed to verify specific therapies as well as main and incidental findings.

RESULTS

While focused on vascular imaging, CTA image quality was sufficient for evaluation of the MSK system in all cases. The underlying cause of IC was diagnosed in run-off CTA as vascular, MSK and a combination in n = 138 (65%), n = 10 (4%), and n = 66 (31%) cases, respectively. Specific vascular or MSK therapy was recorded in n = 123 and n = 9 cases. In n = 82, no follow-up was possible. Clinically relevant extravascular incidental findings were detected in n = 65 patients (30%) with neoplasia, ascites and pleural effusion being the most common findings.

DISCUSSION

Run-off CTA allows identification of vascular, MSK, and combined causes of IC in patients with suspected PAD and can guide specific therapy. CTA also allowed confident detection of crEVIF although detection did not necessarily trigger workup or treatment.

ECG-gated Versus Non-ECG-gated High-pitch Dual-source CT for Whole Body CT Angiography (CTA)

RATIONALE AND OBJECTIVES

To investigate motion artifacts, image quality, and practical differences in electrocardiographic (ECG)-gated versus non-ECG-gated high-pitch dual-source computed tomography angiography (CTA) of the whole aorta.

MATERIALS AND METHODS

Two groups, each including 40 patients, underwent either ECG-gated or non-ECG-gated high-pitch dual-source CTA of the whole aorta. The aortic annulus, aortic valve, coronary ostia, and the presence of motion artifacts of the thoracic aorta as well as vascular contrast down to the femoral arteries were independently assessed by two readers. Additional objective parameters including image noise and signal-to-noise ratio were analyzed.

RESULTS

Subjective and objective scoring revealed no presence of motional artifacts regardless of whether the ECG-gated or the non-ECG-gated protocol was used (P > 0.1). Image acquisition parameters (examination length, examination duration, radiation dose) were comparable between the two groups without significant differences. The aortic annulus, aortic valve, and coronary ostia were reliably evaluable in all patients. Vascular contrast was rated excellent in both groups.

CONCLUSIONS

High-pitch dual-source CTA of the whole aorta is a robust and dose-efficient examination strategy for the evaluation of aortic pathologies whether or not ECG gating is used.

Low-volume contrast medium protocol for comprehensive cardiac and aortoiliac CT assessment in the context of transcatheter aortic valve replacement

RATIONALE AND OBJECTIVES

To investigate the diagnostic performance of a comprehensive computed tomography (CT) protocol for both cardiac and aortoiliac evaluation of patients considered for transcatheter aortic valve replacement (TAVR) using a single, low-volume contrast medium (CM) injection.

MATERIALS AND METHODS

Forty-four TAVR candidates were retrospectively analyzed. All underwent retrospectively electrocardiogram-gated cardiac CT followed by high-pitch CT angiography of the aortoiliac vasculature using one of two single injection protocols of 320 mgI/mL iodine CM: group A (n = 22), iodine delivery rate-based (1.28 gI/s), 60-mL CM volume, 4.0 mL/s flow rate; group B (n = 22), clinical routine protocol, 100-mL CM volume, 4.0 mL/s flow rate. Mean arterial attenuation, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) were calculated. Subjective image quality was assessed.

RESULTS

Aortic root and iliofemoral dimensions could be analyzed in all cases. Patient characteristics showed no significant differences. Mean attenuation at the levels of the aortic root (285.8 ± 83.0 HU vs 327.5 ± 70.8 HU, P = .080) and the iliofemoral access route (256.8 ± 88.5 HU vs 307.5 ± 93.2 HU, P = .071), as well as SNR and CNR were nonsignificantly lower in group A compared to group B. Subjective image quality was equivalent.

CONCLUSIONS

In multimorbid TAVR patients, the performance of a combined CT protocol using a single low-volume CM bolus is feasible with maintained image quality compared to a standard protocol.

Extravascular incidental findings in run-off CT angiography in patients with acute limb ischaemia: incidence and clinical relevance

AIM

To evaluate the incidence and clinical relevance of extravascular incidental findings (EVIFs) in CT angiography of the abdominal aorta and lower extremities (run-off CTA) in patients presenting with acute limb ischaemia (ALI).

MATERIALS AND METHODS

In this institutional review board-approved, retrospective study, 141 run-off CTA examinations conducted between 2005 and 2013 of patients (67 women, mean age 80 years; 74 men, mean age 69 years) presenting with clinical symptoms of ALI were re-evaluated by two radiologists (2 and 7 years of experience in interpreting run-off CTA). Imaging was conducted using 16- and 64-section CT systems. Image acquisition ranged from the costodiaphragmatic recess to the forefoot. The medical history form of each patient served as the standard of reference for assessment of incidence of EVIFs. CT morphology was assessed to assign EVIFs to one of three categories of clinical relevance: (I) immediate, (II) potential, and (III) no clinical relevance.

RESULTS

Thirty-eight patients had category I findings, including four patients (2.8%) with previously unknown malignancy and 67 patients with category II EVIFs. In total 473 extravascular EVIFs were found in 141 patients: 52 category I, 163 category II and 258 category III.

CONCLUSION

EVIFs with immediate clinical relevance are very common in run-off CTA in patients presenting with acute peripheral artery disease. Therefore, it is important to evaluate all body regions included in a CT examination carefully, even if the clinical focus is on vascular evaluation. The adequate classification of these EVIFs is required to avoid possible unnecessary diagnostic work-up with associated risks and costs.

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.

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.

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.

Imaging of the aortic valve with MRI and CT angiography

The aortic valve may be affected by a wide range of congenital and acquired diseases. Echocardiography is the main non-invasive imaging technique for assessing patho-anatomical alterations of the aortic valve and adjacent structures and in many cases is sufficient to establish a diagnosis and/or guide treatment decisions. Recent technological advances in magnetic resonance imaging (MRI) and multidetector computed tomography (MDCT) have enabled these techniques to play a complimentary role in certain clinical scenarios and as such can be useful problem-solving tools. Radiologists should be familiar with the indications, advantages, and limitations of MRI and MDCT in order to advise and direct an appropriate imaging strategy depending upon the clinical scenario. This article reviews the role of MRI and MDCT angiography for assessment of the aortic valve including relevant anatomy, scan acquisition protocols, and post-processing methods. An approach to interpretation and the key imaging features of commonly encountered aortic valvular diseases are discussed.

Predictive factors, management, and clinical outcomes of coronary obstruction following transcatheter aortic valve implantation: insights from a large multicenter registry

OBJECTIVES

This study sought to evaluate the main baseline and procedural characteristics, management, and clinical outcomes of patients from a large cohort of patients undergoing transcatheter aortic valve implantation (TAVI) who suffered coronary obstruction (CO).

BACKGROUND

Very little data exist on CO following TAVI.

METHODS

This multicenter registry included 44 patients who suffered symptomatic CO following TAVI of 6,688 patients (0.66%). Pre-TAVI computed tomography data was available in 28 CO patients and in a control group of 345 patients (comparisons were performed including all patients and a cohort matched 1:1 by age, sex, previous coronary artery bypass graft, transcatheter valve type, and size).

RESULTS

Baseline and procedural variables associated with CO were older age (p < 0.001), female sex (p < 0.001), no previous coronary artery bypass graft (p = 0.043), the use of a balloon-expandable valve (p = 0.023), and previous surgical aortic bioprosthesis (p = 0.045). The left coronary artery was the most commonly involved (88.6%). The mean left coronary artery ostia height and sinus of Valsalva diameters were lower in patients with obstruction than in control subjects (10.6 ± 2.1 mm vs. 13.4 ± 2.1 mm, p < 0.001; 28.1 ± 3.8 mm vs. 31.9 ± 4.1 mm, p < 0.001). Differences between groups remained significant after the case-matched analysis (p < 0.001 for coronary height; p = 0.01 for sinus of Valsalva diameter). Most patients presented with persistent severe hypotension (68.2%) and electrocardiographic changes (56.8%). Percutaneous coronary intervention was attempted in 75% of the cases and was successful in 81.8%. Thirty-day mortality was 40.9%. After a median follow-up of 12 (2 to 18) months, the cumulative mortality rate was 45.5%, and there were no cases of stent thrombosis or reintervention.

CONCLUSIONS

Symptomatic CO following TAVI was a rare but life-threatening complication that occurred more frequently in women, in patients receiving a balloon-expandable valve, and in those with a previous surgical bioprosthesis. Lower-lying coronary ostium and shallow sinus of Valsalva were associated anatomic factors, and despite successful treatment, acute and late mortality remained very high, highlighting the importance of anticipating and preventing the occurrence of this complication.

Coronary obstruction following transcatheter aortic valve implantation: a systematic review

OBJECTIVES

This study sought to evaluate, through a systematic review of the published data, the main baseline characteristics, management, and clinical outcomes of patients suffering coronary obstruction as a complication of transcatheter aortic valve implantation (TAVI).

BACKGROUND

Very few data exist on coronary obstruction after TAVI.

METHODS

Studies published between 2002 and 2012, with regard to coronary obstruction as a complication of TAVI, were identified with a systematic electronic search. Only the studies reporting data on the main baseline and procedural characteristics, management of the complication, and clinical outcomes were analyzed.

RESULTS

A total of 18 publications describing 24 patients were identified. Most (83%) patients were women, with a mean age of 83 ± 7 years and a mean logistic European System for Cardiac Operative Risk Evaluation score of 25.1 ± 12.0%. Mean left coronary artery (LCA) ostium height and aortic root width were 10.3 ± 1.6 mm and 27.8 ± 2.8 mm, respectively. Most patients (88%) had received a balloon-expandable valve, and coronary obstruction occurred more frequently in the LCA (88%). Percutaneous coronary intervention was attempted in 23 cases (95.8%) and was successful in all but 2 patients (91.3%). At 30-day follow-up, there were no cases of stent thrombosis or repeat revascularization, and the mortality rate was 8.3%.

CONCLUSIONS

Reported cases of coronary obstruction after TAVI occurred more frequently in women, in patients receiving a balloon-expandable valve, and the LCA was the most commonly involved artery. Percutaneous coronary intervention was a feasible and successful treatment in most cases. Continuous efforts should be made to identify the factors associated with this life-threatening complication to implement the appropriate measures for its prevention.