Incidental Cardiovascular Abnormalities in the Abdominal Aortic Aneurysm (AAA) Surveillance Population During the AAA Get Fit Trial: A Case Series and Review of the Literature.

Background The prevalence of cardiovascular disease and incidence of major adverse cardiovascular events (MACEs) is very high among the abdominal aortic aneurysm (AAA) surveillance population. Formal assessments of and interventions to reduce cardiovascular risk are not a routine part of the surveillance programme at present. However, its potential importance is highlighted by incidental findings during the AAA Get Fit Trial, a randomised controlled trial which included baseline cardiopulmonary exercise testing (CPET). We speculate that CPET can act as an opportunistic screening programme to identify cardiovascular disease in AAA surveillance patients. Methods The AAA Get Fit Trial was a prospective, randomised controlled trial at a tertiary vascular centre, Manchester University NHS Foundation Trust, conducted between November 2017 and August 2019. Patients underwent CPET at baseline, 8, 16, 24 and 36 weeks as well as clinical history and examination and blood tests. We report on incidental cardiovascular abnormalities diagnosed during the trial. Results Of the 59 participants in the trial, four (6.8%) were identified to have abnormal findings suggestive of unstable cardiovascular disease. On subsequent further investigation, two patients were diagnosed and treated for severe coronary artery disease after abnormal ECG findings were noted during CPET. One patient was diagnosed with unstable angina after obtaining a detailed history on baseline assessment which was treated medically before going on to have a successful elective AAA repair. Conclusions There is a high incidence of MACEs among this high-risk population both pre and perioperatively. Identifying and treating cardiovascular disease among the AAA surveillance population must be a focus of the future AAA screening programme.

Editor's Choice - The Abdominal Aortic Aneurysm Get Fit Trial: A Randomised Controlled Trial of Exercise to Improve Fitness in Patients with Abdominal Aortic Aneurysm.

OBJECTIVE: Ruptured abdominal aortic aneurysm (AAA) carries a mortality rate of up to 80%. Elective repair prevents rupture, but peri-operative mortality remains at 2% - 3%. This mortality rate and long term survival rate are associated with impaired peak oxygen uptake (peak VO2), oxygen uptake at anaerobic threshold (AT) and ventilatory equivalent for CO2 (VECO2) at AT on cardiopulmonary exercise testing (CPET). Improving fitness to optimise these variables could improve peri-operative and long term survival, but the required exercise training suitable for patients with AAA has yet to be established. This randomised controlled trial aimed to evaluate the effectiveness of 24 week, patient directed, community based exercise on CPET measured fitness in AAA surveillance patients. METHODS: This was a prospective randomised controlled trial in a tertiary UK vascular centre conducted using CONSORT guidelines. Patients on AAA surveillance (n = 56) were randomly assigned to either (1) a 24 week community exercise programme (CEP) with choice of gym or home exercises, or (2) standard clinical care including advice on weight loss and exercise. The primary outcome was change in peak VO2 at 24 weeks, with secondary outcomes including AT, VECO2, cardiovascular biomarkers (lipid profile, pro-B-type natriuretic peptide, and high sensitivity C reactive protein, body mass index, and HRQoL. Follow up was at eight, 16, 24, and 36 weeks to evaluate duration of benefit. All analyses were performed on an intention to treat basis. RESULTS: CEP patients (n = 28) achieved mean (95% confidence interval [CI]) improvements from baseline in peak VO2 of 1.5 (95% CI 0.5 - 2.5), 2.1 (95% CI 1.1 - 3.2), 2.3 (95% CI 1.2 - 3.3), and 2.2 (95% CI 1.1, 3.3) mL/kg/min at 8, 16, 24, and 36 weeks, respectively. These changes in CEP patients were significantly greater than those seen in control patients at 16 (p = .002), 24 (p = .031), and 36 weeks (p < .001). There were also significant improvements in AT, triglyceride levels, and HRQoL in CEP patients. CONCLUSION: This CEP significantly improved those CPET parameters associated with impaired peri-operative and long term survival in patients following AAA repair. These improvements were maintained at 12 weeks following the end of the programme.

Early Results Using N-Terminal pro-B-Type Natriuretic Peptide (pro-BNP) as a Biomarker for the Efficacy of Secondary Extension Technique (SET) in Improving Myocardial Function in Dialysis Patients With High Flow Fistulas.

BACKGROUND: The association of dialysis fistulas and heart failure is believed to be due to high cardiac output. N-terminal pro-B-Type Natriuretic Peptide (pro-BNP) which is secreted by the cardiac ventricles in response to excessive stretching of the myocytes has been used as a marker of heart failure with 90% sensitivity. We report our early experience using pro-BNP levels to test the efficacy of the novel 'secondary extension technique' (SET) in improving myocardial function by reducing fistula flow. METHODS: Eleven patients with high fistula flows (>3000 mL/m, all brachio-cephalic) and raised pro-BNP underwent SET between 2011 and 2015. SET involves extending the anastomosis from brachial to either proximal radial or ulnar arteries. We measured pro-BNP levels, fistula flow and clinical improvements both pre and post operatively. RESULTS: SET resulted in a median (IQR) flow rate decrease of 57.9 (11.9)% which correlated with a fall in pro-BNP of 69.6 (39)%. Seven of the 11 patients in the series pro-BNP level returned to a normal value at average follow-up of 3 months post SET. All patients had HOF-related symptom resolution post-procedure and remained asymptomatic at last follow-up CONCLUSIONS: Our pilot data suggests that SET is an effective way of reducing fistula flow. It also shows that BNP may be a reliable biomarker in assessing the impact of the technique on cardiac function. These results warrant further investigation in the form of a definitive, multicenter study.

Patients on AAA Surveillance are at Greater Threat of Cardiovascular Events or Malignancy than their AAA: Outcomes of AAA Surveillance over 19 years at a Tertiary Vascular Centre.

BACKGROUND: To analyse 19 years' worth of data from a Major UK Vascular Centre to determine the outcome of patients after they enter abdominal aortic aneurysm (AAA) surveillance (surgery, death, discharge or transfer), this may inform interventions to improve these outcomes in the AAA surveillance population. METHODS: This was a retrospective analysis of a prospectively collected database of outcomes of every patient entered on AAA surveillance at Manchester University NHS Foundation Trust - Wythenshawe Hospital between September 2000 and June 2019. Analyses included what proportion suffered death, discharge, transfer or surgery whilst on surveillance. Multi-variate analysis was used to determine the effect of initial AAA size, age when entering surveillance and gender. Boxplots were produced in those who had already reached an outcome to determine historic median times. Causes of death/discharge were also analysed. RESULTS: One thousand nine hundred fifty-one patients were identified from the databased after data cleaning and were included in the final analysis. Thirty-two percent of patients had died, 23.8% had surgery, 13.3% were discharged due to worsening/severe comorbidity, 3.1% had been transferred and 27.7% were still active in surveillance. A longer time to surgery was significantly associated with increasing age on entering surveillance OR (95% CI) 0.95 (0.94-0.96) (P < 0.001), smaller initial AAA size 4.26 (3.80-4.78) (P < 0.001) but not female gender. Impaired survival was associated with increasing age 1.06 (1.05-1.07) (P < 0.001), initial AAA size, 1.56 (1.39-1.74) (P < 0.001) and female gender 1.40 (1.18-1.67) (P < 0.001). Overall, death occurred more frequently than operative repair every year over all 15 years. Out of the deaths where cause was known (n = 401), 34.9% (n = 108) were due to cardiovascular events, 27.3% (n = 109) due to malignancy (primarily lung), and 19.3% due to respiratory disease. CONCLUSIONS: Based on this data, death, primarily due to cardiovascular events, is a more likely outcome than operative repair in patients on AAA surveillance and is associated with increasing age, increasing AAA size and female gender. A median time on surveillance of over three and a half years provides sufficient time to affect subsequent health outcomes in this population and therefore a shift of focus of AAA surveillance programmes to address cardiovascular, malignancy and respiratory disease risk is warranted.

Arteriovenous Fistula Surveillance Using Tomographic 3D Ultrasound.

OBJECTIVE: A well functioning arteriovenous fistula (AVF) is essential for haemodialysis. Despite regular duplex ultrasound (DUS) a significant number of AVFs fail. Tomographic 3D ultrasound (tUS) creates a 3D image of the AVF that can be interpreted by the clinician. DUS, tUS, and fistulograms were compared for the identification and measurement of flow limiting stenosis. METHODS: Patients with AVF dysfunction on routine Transonic surveillance, defined as (1) > 15% reduction in flow on two consecutive occasions, (2) > 30% reduction in flow on one occasion, (3) flow of < 600 mL/sec, (4) presence of recirculation, underwent DUS. AVF tUS imaging was performed prior to fistulography. All fistulograms were reported by the same consultant radiologist and tUS images by the same vascular scientist blinded to the fistulogram results. Maximum diameter reduction in all stenoses were measured using all three imaging techniques. RESULTS: In 97 patients with 101 stenoses, the mean (± standard deviation [SD]) severity of stenosis was 63.0 ± 13.9%, 65.0 ± 11.6%, and 64.8 ± 11.7% for the fistulograms, DUS, and tUS respectively. The mean (± SD) time between ultrasound and fistulography imaging was 15.0 ± 14.5 days. Assuming the fistulogram as the "gold standard", Bland-Altman agreement for DUS was -1.9 ± 15.5% (limit of agreement [LOA] -32.2 - 28.4) compared with -1.7 ± 15.4% (LOA -31.9 - 28.4) for tUS. Median (± interquartile range) time to complete the investigation was 09:00 ± 03:19 minutes for DUS and 03:13 ± 01:56 minutes for tUS (p < .001). CONCLUSION: DUS and tUS were equally accurate at detecting AVF complications but tUS investigation requires less skill and was significantly quicker than DUS.

Endovascular Management of an Acquired Carotid-Jugular Fistula in a Child.

BACKGROUND There is a paucity of published literature on carotid-jugular fistulae in children. These injuries are uncommon in the pediatric age group and most of the current practice in managing such injuries is extrapolated from similar injuries in the adult population. CASE REPORT We report a case of an acquired carotid-jugular fistula (CJF) following penetrating neck trauma in a 12-year-old male, treated by minimally invasive endovascular covered stent. Successful endovascular management was achieved in this case with anatomical and symptomatic resolution at 6 weeks and normal duplex ultrasound at 18 months. CONCLUSIONS The rarity of carotid-jugular fistulae in children means there is a lack of consensus for the appropriate management in the available literature. This case report adds to the evidence for endovascular management of this condition in a pediatric population.