Long-term Imaging Surveillance Research Articles

Comparison of open thoracoabdominal repair for chronic aortic dissections and aneurysms

ObjectiveAortic dissection is common in patients undergoing open surgical repair of thoracoabdominal aortic aneurysms (TAAAs). Most often, dissection is chronic and is associated with progressive aortic dilatation. Because contemporary outcomes in chronic dissection are not clearly understood, we compared patient characteristics and outcomes after open TAAA repair between patients with chronic dissection and those with non-dissection aneurysm. MethodsWe retrospectively analyzed data from 3470 open TAAA repairs performed in a single practice. Operations were for non-dissection aneurysm in 2351 (67.8%) and chronic dissection in 1119 (32.2%). Outcomes included operative mortality and adverse events, a composite variable comprising operative death and persistent (present at discharge) stroke, paraplegia, paraparesis, and renal failure necessitating dialysis. Logistic regression identified predictors of operative mortality and adverse events. Time-to-event analyses examined survival, death, repair failure, subsequent progressive repair, and survival free of failure or subsequent repair. ResultsCompared with patients with non-dissection aneurysm, those with chronic dissection were younger, had fewer atherosclerotic risk factors, and were more likely to have heritable thoracic aortic disease and undergo extent II repair. The operative mortality rate was 8.5% (n = 296) overall and was higher in non-dissection aneurysm patients (n = 217; 9.2%) than in chronic dissection patients (n = 79; 7.1%; P = .03). Adverse events were less frequent (P = .01) in patients with chronic dissection (n = 145; 13.0%), 22 (2.0%) of whom had persistent paraplegia. Chronic dissection was not predictive of operative mortality (P = .5) or adverse events (P = .6). Operative mortality and adverse events, respectively, were independently predicted by emergency repair (odds ratio [OR], 3.46 and 2.87), chronic kidney disease (OR, 1.74 and 1.81), extent II TAAA repair (OR, 1.44 and 1.73), increasing age (OR, 1.04/year and 1.04/year), and increasing aortic cross-clamp time (OR, 1.02/minutes and 1.02/minutes). Patients with chronic dissection had lower 10-year unadjusted mortality (42% vs 69%) but more frequent repair failure (5% vs 3%) and subsequent repair for progressive aortic disease (11% vs 5%) than patients with non-dissection aneurysm (P < .001); these differences were no longer statistically significant after adjustment. ConclusionsOutcomes of open TAAA repair vary by aortic disease type. Emergency repairs and atherosclerotic diseases most commonly occur in patients with non-dissection aneurysm and independently predict operative mortality. Repair of chronic dissection is associated with low rates of adverse events, including operative mortality and persistent paraplegia, along with reasonable late survival and good durability. However, patients with chronic dissection tend to more commonly undergo subsequent repair to treat progressive aortic disease, which emphasizes the need for robust long-term imaging surveillance protocols.

CIRSE Standards of Practice on Management of Endoleaks Following Endovascular Aneurysm Repair.

Endoleaks represent the most common complication after EVAR. Some types are associated with ongoing risk of aneurysm rupture and necessitate long-term surveillance and secondary interventions. This document, as with all CIRSE Standards of Practice documents, will recommend a reasonable approach to best practices of managing endoleaks. This will include imaging diagnosis, surveillance, indications for intervention, endovascular treatments and their outcomes. Our purpose is to provide recommendations based on up-to-date evidence, updating the guidelines previously published on this topic in 2013. The writing group was established by the CIRSE Standards of Practice Committee and consisted of clinicians with internationally recognised expertise in endoleak management. The writing group reviewed the existing literature performing a pragmatic evidence search using PubMed to select publications in English and relating to human subjects up to 2023. The final recommendations were formulated through consensus. Endoleaks may compromise durability of the aortic repair, and long-term imaging surveillance is necessary for early detection and correct classification to guide potential re-intervention. The majority of endoleaks that require treatment can be managed using endovascular techniques. This Standards of Practice document provides up-to-date recommendations for the safe management of endoleaks.

Risk of second brain tumour after radiotherapy for pituitary adenoma or craniopharyngioma: a retrospective, multicentre, cohort study of 3679 patients with long-term imaging surveillance

Radiotherapy is a valuable treatment in the management algorithm of pituitary adenomas and craniopharyngiomas. However, the risk of second brain tumour following radiotherapy is a major concern. We assessed this risk using non-irradiated patients with the same primary pathology and imaging surveillance as controls. In this multicentre, retrospective cohort study, 4292 patients with pituitary adenoma or craniopharyngioma were identified from departmental registries at six adult endocrine centres (Birmingham, Oxford, Leeds, Leicester, and Bristol, UK and Ferrara, Italy). Patients with insufficient clinical data, known genetic predisposition to or history of brain tumour before study entry (n=532), and recipients of proton beam or stereotactic radiotherapy (n=81) were excluded. Data were analysed for 996 patients exposed to 2-dimensional radiotherapy, 3-dimensional conformal radiotherapy, or intensity-modulated radiotherapy, and compared with 2683 controls. Over 45 246 patient-years, second brain tumours were reported in 61 patients (seven malignant [five radiotherapy, two controls], 54 benign [25 radiotherapy, 29 controls]). Radiotherapy exposure and older age at pituitary tumour detection were associated with increased risk of second brain tumour. Rate ratio for irradiated patients was 2·18 (95% CI 1·31-3·62, p<0·0001). Cumulative probability of second brain tumour was 4% for the irradiated and 2·1% for the controls at 20 years. Irradiated adults with pituitary adenoma or craniopharyngioma are at increased risk of second brain tumours, although this risk is considerably lower than previously reported in studies using general population controls with no imaging surveillance. Our data clarify an important clinical question and guide clinicians when counselling patients with pituitary adenoma or craniopharyngioma on the risks and benefits of radiotherapy. Pfizer.

Radiotherapy for adults with pituitary adenoma or craniopharyngioma is associated with increased risk of second brain tumour : A multi-centre study of 3,613 patients with long-term imaging surveillance

Radiotherapy for adults with pituitary adenoma or craniopharyngioma is associated with increased risk of second brain tumour : A multi-centre study of 3,613 patients with long-term imaging surveillance

Late type III endoleaks are common in early generation Endologix AFX stent grafts

ObjectiveEarly generation Endologix AFX endovascular abdominal aortic aneurysm (AAA) stent graft devices are at risk of developing type IIIa (intercomponent/overlap-related) as well as type IIIb (fabric tear) endoleaks over time. Current follow-up studies are limited to short (<24 months) and midterm (24-48 months) reports. The purpose of this study was to identify the incidence of type III endoleaks associated with these endografts over a long-term follow-up (>4 years) period and discuss current management strategies. MethodsA retrospective, single-institution cohort analysis of all Endologix AFX endografts implanted from October 2011 to October 2016 was performed. Patient characteristics, imaging, and follow-up were obtained via chart review. Type III endoleaks were characterized based on computed tomography angiogram/operative findings and confirmed by two surgeons. Statistical analysis was performed with SAS v9.4. ResultsSixty-three patients underwent AFX stent graft implantation for aneurysmal disease. Forty-seven patients comprised the final cohort for analysis after exclusions were made for primary iliac aneurysms as well as off-label use of the device (eg, hypogastric snorkel) or primary occlusive indications. The average age was 73.3 years, with the longest follow-up being 8.7 years (median, 5.2 years). Most AAAs (89.2%) were fusiform, with initial median diameter 5.5 cm. Initial 30-day mortality was 0%. Of the initial cohort, 10 (21.3%) type III endoleaks were treated, of which six (60%) were type IIIa and four (40%) were type IIIb. By time-to-event analysis at latest follow-up, freedom from type III intervention was 48% at 8 years. The median time to type III endoleak discovery was 4.7 years (range, 1.1-7.2 years), an interval that was similar for type IIIa and type IIIb leak types (P = .73). Patients with type III endoleaks had average sac growth of 1.3 cm over the follow-up interval compared with a net decrease for patients without type III endoleaks (P < .0001). Of the 10 patients treated for type III leaks, seven (70%) underwent complete endovascular re-lining, one (10%) had partial re-lining, and two (20.0%) underwent open endograft explant with aortic graft reconstruction. Reintervention 30-day mortality was 0% for all approaches. ConclusionsEarly generation Endologix AFX stent grafts have a high rate of type III endoleaks, with freedom from type III leak <50% at 8-year follow-up. Most of these are not detected until several years (>4.5 years) after initial implantation, beyond the range of the follow-up interval of most published reports. Long-term imaging surveillance is critical, and a low threshold for complete relining should be considered with any sign of sac enlargement, even if endoleak is not clearly demonstrated in patients with early generation Endologix AFX grafts.

Pre-anthracycline left ventricular ejection fraction (LVEF) assessment and long-term cardiovascular (CV) outcomes in adolescent and young adult (AYA) lymphoma survivors.

e24060 Background: Anthracyclines are known to cause long-term cardiotoxicity. There are no specific guidelines for CV screening and follow-up of AYA patients treated with anthracyclines. Pediatric guidelines focus on long-term imaging surveillance, while for adults, LVEF assessment prior to anthracyclines is recommended. Multiple studies have demonstrated LVEF assessment rarely impacts treatment decisions, especially in the absence of CV symptoms/risk factors, adds to unnecessary costs and delays treatment initiation. Our study aimed to determine the pre-treatment LVEF assessment practices in AYA lymphoma patients treated with anthracyclines and its association with long-term cardiotoxicity. Methods: AYA survivors diagnosed with lymphoma &gt; 5 years ago and treated with anthracyclines at age 15-39 years were identified in a retrospective single institution registry. To ensure adequate follow-up, at least 2 follow-up visits during 2015-19 were required. Data abstracted on eligible subjects included documentation of pre-treatment LVEF evaluation, clinical rationale and treatment regimen. CV risk factors and events were collected pre-treatment and during follow-up. Descriptive statistics were used to summarize data. Results: 64/115 (56%) of AYA lymphoma patients underwent pre-treatment LVEF assessment. Rationale for/against LVEF assessment was rarely documented: low CV risk was recorded as rationale for no LVEF assessment in 2 subjects. Among AYAs who underwent pre-treatment LVEF assessment, no significant abnormalities were detected and no changes in subsequent treatment plans were found. During median follow-up of 6.7 (inter-quartile range 5.4-9.5) years, 6/115 (5%) experienced CV events. Only 2 (1.7%) survivors experienced potential anthracycline-related CV events: 1 moderate cardiomyopathy at 9 years, 1 peri-partum cardiomyopathy and atrial fibrillation due to post-radiation SVC occlusion at 15 years post-treatment. Both these AYAs (aged 38 and 31 years at time of CV events) also had other CV risk factors- family history, smoking, obesity, and hyperlipidemia. Four (3.5%) survivors’ experienced CV events (1 sinus tachyarrhythmia, 1 junctional rhythm, 2 acute/asymptomatic drop in LVEF) unrelated to anthracyclines with clear alternative etiology e.g. sepsis/symptom burden. There was no correlation between having pre-treatment LVEF assessment and occurrence of CV events. 13/115 (11.3%) developed new CV risk factors: 4 hypertension, 6 hyperlipidemia, 3 diabetes. Conclusions: Pre-treatment LVEF assessment is done inconsistently in AYA lymphoma patients but does not impact initial treatment or predict late cardiotoxicity. CV events in long-term AYA lymphoma survivors are rare but evaluation of CV risk factors, early detection and management may be more important than focusing on LVEF assessment.

Evolution of conservative treatment of acute traumatic aortic injuries: lights and shadows.

The objective of this study is to compare early and long-term results in terms of survival and aortic complications for traumatic aortic injuries depending on the initial management strategy. From January 1980 to January 2017, 101 patients with aortic injuries were divided into 3 groups according to management strategy at admission: 60 patients, conservative management; 26 patients, open surgery and 15 patients, endovascular repair. The groups were similar in terms of gender and trauma severity scores. All but 1 aortic-related complications and aortic-related mortality occurred in the conservative group (11.6% conservative vs 2.4% in both surgical and endovascular groups, P = 0.091). Total follow-up was 1109.27 patient-years. Survival in the conservative, surgical and endovascular group was 71.7%, 80.8% and 79.4% at 1 year, 68.2%, 80.8% and 79.4% at 5 years and 63.9%, 72.7% and 79.4% at 10 years, respectively (log-rank = 0.218). The rate of aortic-related complications was 58.3% in the conservative cohort. Cox regression identified the following risk factors for aortic-related complications: aortic injuries grade >I [odds ratio (OR), 3.05; P = 0.021], Trauma Injury Severity Score >50% (OR 1.21; P = 0.042) and the decade of treatment (OR 0.49; P = 0.011). Minimal aortic injuries seem to be an amenable target for medical management, but patients remain at risk of developing aortic-related complications. Close, long-term imaging surveillance is mandatory to detect such complications at an early stage.

Evaluation of Delayed Endoleak Compared with Early Endoleak after Endovascular Aneurysm Repair

PurposeTo identify prevalence and evaluate outcomes of delayed endoleak (DEL) compared with early endoleak (EEL) after endovascular aortic aneurysm repair (EVAR). Materials and MethodsData of 164 patients who underwent elective EVAR at a single center were retrospectively analyzed. DEL was defined as any type of endoleak that was first detected ≥ 12 months after EVAR. Patients who had < 1 year of follow-up were excluded. Endoleak was classified into a more aggressive category if a patient had > 1 type of endoleak. Analysis included 81 patients (82.7% male). Mean age was 73.1 years ± 9.3. Median follow-up duration was 43 months (range, 12–135 months). ResultsEndoleak was present in 32 patients (39.5%), including 21 EEL (25.9%) and 11 DEL (13.6%). DEL consisted of 2 type I, 5 type II, 1 type III, and 3 type V (endotension). Median time to detection was 45 months (range, 15–60 months), and median follow-up duration was 62 months (range, 37–104 months). Compared with EEL, DEL had larger aneurysm diameters and higher rates of non–type II endoleak and reintervention. Type II DEL also required more reintervention procedures than type II EEL. ConclusionsDEL had a noteworthy incidence and occurred late after EVAR. It predominantly consisted of non–type II endoleak and appeared to have more reinterventions than EEL. Meticulous long-term imaging surveillance to identify and manage DEL is critical.

Multi-Velocity Encoding Four-Dimensional Flow Magnetic Resonance Imaging in the Assessment of Chronic Aortic Dissection.

Background: Chronic descending thoracic aortic dissection (CDTAD) following surgical repair of ascending aortic dissection requires long-term imaging surveillance. We investigated four-dimensional (4D)-flow magnetic resonance imaging (MRI) with a novel multi-velocity encoding (multi-VENC) technique as an emerging clinical method enabling the dynamic quantification of blood volume and velocity throughout the cardiac cycle. Methods: Patients with CDTAD (n = 10; mean age, 55.1 years; standard deviation (SD) 10.8) and healthy volunteers (n = 9; mean age, 37.1 years; SD 11.4; p < 0.01) underwent 3T MRI, and standard views and 4D-flow data were obtained. Flow measurements were made in selected regions of interest within the ascending and descending thoracic aorta. Results: The overall flow profile at peak systole was reduced in the false lumen (FL) compared with the true lumen (TL) and normal aortas (p < 0.05 for velocity < 0.4 m/s). Peak systolic flow rate per aortic lumen area (mL/s/cm 2 ) was lower in the FL than in the TL (p < 0.05), and both rates were lower than that of control aortas (p < 0.05). Blood flow reversal was higher in the FL than in the TL throughout the descending aorta in CDTAD patients (p < 0.05). A derived pulsatility index was elevated in the TL compared with that in the FL in CDTAD patients. Generated pathline images demonstrated flow patterns in detail, including sites of communication between the true and FL. Conclusions: 4D-flow MRI revealed FL blood flow and reduced blood flow velocity and flow rate in the TL of CDTAD patients compared with normal aortas of healthy participants. Thus, multi-VENC 4D-flow MRI could serve as an adjunct in the long-term assessment of CDTAD following surgical repair of ascending aortic dissection.

Endovascular aneurysm repair: is imaging surveillance robust, and does it influence long-term mortality?

Endovascular aneurysm repair (EVAR) is the dominant treatment strategy for abdominal aortic aneurysms. However, as a result of uncertainty regarding long-term durability, an ongoing imaging surveillance program is required. The aim of the study was to assess EVAR surveillance in Scotland and its effect on all-cause and aneurysm-related mortality. A retrospective analysis of all EVAR procedures carried out in the four main Scottish vascular units. The primary outcome measure was the implementation of post-EVAR imaging surveillance across Scotland. Patients were identified locally and then categorized as having complete, incomplete, or no surveillance. Secondary outcome measures were all-cause mortality and aneurysm-related mortality. Cause of death was obtained from death certificates. Data were available for 569 patients from the years 2001 to 2012. All centers had data for a minimum of 5 contiguous years. Surveillance ranged from 1.66 to 4.55 years (median 3.03 years). Overall, 53 % had complete imaging surveillance, 43 % incomplete, and 4 % none. For the whole cohort, all-cause 5-year mortality was 33.5 % (95 % confidence interval 28.0-38.6) and aneurysm-related mortality was 4.5 % (.8-7.3). All-cause mortality in patients with complete, incomplete, and no imaging was 49.9 % (39.2-58.6), 19.1 % (12.6-25.2), and 47.2 % (17.7-66.2), respectively. Aneurysm-related mortality was 3.7 % (1.8-7.4), 4.4 % (2.2-8.9), and 9.5 % (2.5-33.0), respectively. All-cause mortality was significantly higher in patients with complete compared to incomplete imaging surveillance (p < 0.001). No significant differences were observed in aneurysm-related mortality (p = 0.2). Only half of EVAR patients underwent complete long-term imaging surveillance. However, incomplete imaging could not be linked to any increase in mortality. Further work is required to establish the role and deliverability of EVAR imaging surveillance.

Current Opinions on Medical Radiation: A Survey of Oncologists Regarding Radiation Exposure and Dose Reduction in Oncology Patients

The aim of this study was to evaluate oncologists' opinions about the use of ionizing radiation in medical imaging of oncology patients. An electronic survey was e-mailed to 2,725 oncologists at the top 50 National Cancer Institute-funded cancer centers. The survey focused on opinions on CT dose reduction in oncology patients and current philosophies behind long-term imaging in these patients. The response rate was 15% (415 of 2,725). Eighty-two percent of respondents stated that their patients or families have expressed anxiety regarding radiation dose from medical imaging. Although fewer than half of oncologists (48%) did not know whether CT dose reduction techniques were used at their institutions, only 25% were concerned that small lesions may be missed with low-dose CT techniques. The majority of oncologists (63%) follow National Comprehensive Cancer Network guidelines for imaging follow-up, while the remainder follow other national guidelines such as those of the Children's Oncology Group, the American Society of Clinical Oncology, or clinical trials. Ninety percent of respondents believe that long-term surveillance in oncology patients is warranted, particularly in patients with breast cancer, melanoma, sarcoma, and pediatric malignancies. The majority of oncologists would consider the use of low-dose CT imaging in specific patient populations: (1) children and young women, (2) those with malignancies that do not routinely metastasize to the liver, and (3) patients undergoing surveillance imaging. Cumulative radiation exposure is a concern for patients and oncologists. Among oncologists, there is support for long-term imaging surveillance despite lack of national guidelines.

A computational framework for investigating the positional stability of aortic endografts

Endovascular aneurysm repair (Greenhalgh in N Engl J Med 362(20):1863-1871, 2010) techniques have revolutionized the treatment of thoracic and abdominal aortic aneurysm disease, greatly reducing the perioperative mortality and morbidity associated with open surgical repair techniques. However, EVAR is not free of important complications such as late device migration, endoleak formation and fracture of device components that may result in adverse events such as aneurysm enlargement, need for long-term imaging surveillance and secondary interventions or even death. These complications result from the device inability to withstand the hemodynamics of blood flow and to keep its originally intended post-operative position over time. Understanding the in vivo biomechanical working environment experienced by endografts is a critical factor in improving their long-term performance. To date, no study has investigated the mechanics of contact between device and aorta in a three-dimensional setting. In this work, we developed a comprehensive Computational Solid Mechanics and Computational Fluid Dynamics framework to investigate the mechanics of endograft positional stability. The main building blocks of this framework are: (1) Three-dimensional non-planar aortic and stent-graft geometrical models, (2) Realistic multi-material constitutive laws for aorta, stent, and graft, (3) Physiological values for blood flow and pressure, and (4) Frictional model to describe the contact between the endograft and the aorta. We introduce a new metric for numerical quantification of the positional stability of the endograft. Lastly, in the results section, we test the framework by investigating the impact of several factors that are clinically known to affect endograft stability.

Dual-Energy Computed Tomography Imaging of the Aorta After Endovascular Repair of Abdominal Aortic Aneurysm

Endovascular repair is increasingly considered a less-invasive alternative to open repair of abdominal aortic aneurysm. However, there are still many potential complications of endovascular repair, including endoleaks, graft migration, thrombosis, and fistula formation. Endoleak is the most common complication for which these patients undergo long-term imaging surveillance. Most centers acquire computed tomographic (CT) data before contrast administration and during an arterial and delayed phase of aortic enhancement after the administration of intravenous contrast material to optimize detection of endoleaks. Although this technique works well, the downside is significant patient radiation exposure. Although the carcinogenic risk of ionizing radiation because of CT exposure is low, it has been linked to an increase in the lifelong risk of developing fatal cancers. Furthermore, this risk is cumulative and increases with multiple radiation exposure, as is true in surveillance after endovascular repair. As a result, considerable research is being performed to optimize CT protocols in an effort to decrease radiation dose. One such approach is to image these patients with recently introduced dual source dual-energy CT system. Using this technique, virtual noncontrast data may be generated from a postcontrast acquisition which may obviate the routine acquisition of noncontrast acquisition, thus decreasing radiation dose. In this article, we discuss the role of dual energy CT imaging in evaluation of patients after endovascular repair of abdominal aortic aneurysm.