Publications by authors named "Ian M Williams"
Objectives: A multicentre European randomized control trial - European Uncomplicated Type B Aortic Repair (EU-TBAR) is being developed to compare pre-emptive TEVAR with custom-made devices vs conventional OMT. The pre-trial set-up is confluent on different pillars, including evaluation of 1) European activity, trends, and governance, 2) outcome reporting, and 3) cost evaluation. This article aimed to demonstrate the observational cross-sectional survey results from participating centres and highlight the risk assessment, activity, practices, and governance of uncomplicated type B aortic dissection (uTBAD).
View Article and Find Full Text PDFIliac branch endoprosthesis for endovascular treatment of complex aorto-iliac aneurysms - from device design to practical experience: how to translate physiology considerations into clinical applications.
Apostolos G Pitoulias Mario D Oria Konstantinos P Donas Matti Jubouri Damian M Bailey Ian M Williams
Exp Physiol
November 2024
Article Synopsis
- - This article reviews current literature and expert opinions on using iliac branch endoprosthesis (IBE) for treating complex abdominal aortic aneurysms (AAA) that also involve the iliac arteries.
- - Around 25% of AAA patients have aneurysms that extend into ilac vessels, complicating standard endovascular aortic repair (EVAR) procedures and requiring careful assessment to ensure proper treatment.
- - The IBE is shown to be an effective and durable treatment option for complex aorto-iliac aneurysms, offering results comparable to open surgery but with lower risks, while also preserving pelvic circulation to avoid potential complications.
Article Synopsis
- Microvascular dysfunction contributes to insulin resistance, particularly in individuals with a genetic variant (G allele) that reduces CD36 expression, impacting blood vessel function and glucose disposal.* -
- Through various experimental methods, the study found that while CD36-deficient mice and humans showed improved insulin-stimulated glucose disposal, they had issues with blood volume response and vascular compliance, indicating a paradoxical relationship between microvascular resistance and insulin sensitivity.* -
- The findings suggest that while CD36 deficiency may enhance glucose disposal efficiency, it simultaneously hampers the microvasculature's response to insulin, affecting oxygen delivery and energy metabolism in muscle and heart tissues.*
Endothelial β1-integrins are necessary for microvascular function and glucose uptake.
Am J Physiol Endocrinol Metab
December 2024
Microvascular insulin delivery to myocytes is rate limiting for the onset of insulin-stimulated muscle glucose uptake. The structural integrity of capillaries of the microvasculature is regulated, in part, by a family of transmembrane adhesion receptors known as integrins, which are composed of an α and a β subunit. The integrin β1 (itgβ1) subunit is highly expressed in endothelial cells (ECs).
View Article and Find Full Text PDFArticle Synopsis
- Heart failure is increasingly challenging due to an ageing population, but mechanical circulatory support devices like ventricular assist devices and Extracorporeal Membrane Oxygenation (ECMO) are evolving to help manage this condition.
- This review highlights how these devices function to relieve pressure on the heart and improve physiological measures such as stroke volume and intracardiac pressure, which begin to change immediately after device implantation.
- While devices like Impella and TandemHeart have shown positive effects on heart function in patients with cardiogenic shock, more research is needed to evaluate their long-term clinical outcomes, and choosing the right device depends on individual patient circumstances.
Article Synopsis
- * The study focused on the integrin β1 subunit in endothelial cells, revealing that its absence led to impaired microvascular function and glucose uptake in response to insulin.
- * Findings showed that mice lacking endothelial integrin β1 had decreased capillary flow and density, resulting in compromised insulin-mediated glucose delivery, highlighting its importance for proper muscle function.
Article Synopsis
- Cardiogenic shock (CS) is a severe condition caused by heart dysfunction leading to low blood pressure and poor blood circulation, requiring urgent medical intervention like mechanical circulatory support (MCS) devices.
- This review focuses on evaluating the effectiveness of MCS in improving survival rates, and the role of drugs and non-surgical devices in treating CS to prevent complications and improve patient outcomes.
- While MCS devices vary in their clinical outcomes, intra-aortic balloon pump (IABP) appears to offer the best short-term results, whereas ECMO is highlighted for its long-term effectiveness in managing CS.
Long-Term Survival and Reintervention Following Thoracic Endovascular Aortic Repair in Blunt Traumatic Thoracic Aortic Injury: A Systematic Review and Meta-Analysis.
Matti Jubouri Abdelaziz O Surkhi Mohammed Al-Tawil Alexander Geragotellis Tareq Z I Abdaljawwad Ian M Williams
Ann Vasc Surg
December 2024
Article Synopsis
- * A systematic review analyzed 27 studies involving 1,498 BTAI patients treated with TEVAR, finding an overall mortality rate of 12% and long-term survival rates of around 90% at 1 year post-treatment.
- * The findings suggest that while BTAI carries significant risks, TEVAR offers a safe and effective management option with a low likelihood of needing additional procedures, emphasizing the importance of timely diagnosis and transfer to trauma centers.
Article Synopsis
- This study looked at factors that can increase the risk of developing abdominal aortic aneurysm (AAA) among people in South East Wales from 1993 to 2015.
- Out of nearly 7,000 patients, 275 were found to have AAA, with most of them being older men.
- The researchers identified several risk factors for AAA, including family history, previous surgeries, heart disease, diabetes, smoking, and more, which can help improve future health screenings.
Article Synopsis
- Dysfunction of endothelial insulin delivery contributes to insulin resistance, with CD36 playing a key role in this process as a fatty acid transporter.
- Research shows that both CD36-deficient mice and humans demonstrate enhanced glucose disposal despite signs of endothelial dysfunction, such as reduced blood vessel compliance.
- This paradox suggests that while CD36 deficiency impairs insulin signaling in microvascular cells, it may simultaneously lead to changes in muscle gene expression that improve glucose utilization.
Article Synopsis
- - Thoracic endovascular aortic repair (TEVAR) has improved the treatment for type B aortic dissections (TBADs), but covering the left subclavian artery is crucial for effective outcomes, necessitating an additional procedure called aortic arch debranching.
- - A study analyzed 58 TBAD patients who underwent TEVAR from 2005 to 2021, revealing that nearly half had complicated conditions, with the left subclavian artery bypass performed in 26% of cases, and highlighting a notable risk of stroke.
- - The findings showed a 17.2% reintervention rate and a 29.3% mortality rate, indicating that while TEVAR and aortic arch debranching can
Background: Abdominal aortic aneurysm (AAA) has a prevalence of 4.8%. AAA rupture is associated with significant mortality, thus surgical intervention is generally required once the aneurysm diameter exceeds 5.
View Article and Find Full Text PDFIntroduction: Endovascular aneurysm repair (EVAR) has rapidly become the preferred management of abdominal aortic aneurysm (AAA). Sac regression status post-EVAR has been linked to clinical outcomes as well as the choice of EVAR device. The aim of this narrative review is to investigate the relationship between sac regression and clinical outcomes post-EVAR in AAA.
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- Collateral arteries serve as natural bypasses that maintain blood flow during artery blockages, and enhancing their development could be a potential treatment for cardiac ischemia.
- Research using imaging and modeling on neonate and adult mouse hearts revealed that neonate collaterals are more effective at restoring blood flow compared to those in adults.
- In adults, the growth of coronary arteries involved adding branches rather than increasing size, leading to reduced effectiveness, highlighting the difference in collateral artery functionality between fetal and adult hearts and emphasizing their importance for heart regeneration and therapeutic strategies.
Article Synopsis
- - Endovascular aortic repair (EVAR) is the leading treatment for abdominal aortic aneurysms (AAA), focusing on sealing the aneurysmal sac to achieve sac regression, which is important for patient outcomes.
- - Key factors that positively affect sac regression include female sex, larger sac sizes, higher fibrinogen levels, and low intra-aneurysmal pressure, while renal impairment and ischemic heart disease tend to have negative effects.
- - Newer generation EVAR devices, particularly the Fenestrated Anaconda, show the most promising results in promoting sac regression, underscoring the importance of considering both patient conditions and device choices for optimal AAA treatment outcomes.
Article Synopsis
- The safety of exercise for patients with abdominal aortic aneurysms (AAA) is debated due to concerns about the risk of rupture from increased blood pressure during physical activity.
- This review involves experts from various medical fields who argue that patients should not avoid rigorous exercise and that the fear of rupture is often overstated.
- By examining the positive effects of exercise and providing tailored safety recommendations, the authors suggest that the benefits of exercise and cardiopulmonary testing exceed the short-term risks related to AAA rupture.
Article Synopsis
- Preeclampsia (PE) is a common pregnancy issue that is more likely to occur in women with obesity, although only a small percentage of these women actually develop PE.
- Researchers studied women with obesity during pregnancy to find specific lipid markers that could indicate the presence of PE, using blood samples collected throughout the trimesters.
- The study found that targeted lipid analysis revealed higher levels of certain lipids in the third trimester for women with PE, while earlier trimesters showed no predictive lipid differences; race and pregnancy stage also influenced lipid variations.
Article Synopsis
- - The study investigated the effects of personal protective equipment (PPE) on headaches, cerebral blood flow, and cognitive performance during surgical simulations among higher surgical trainees.
- - Results showed that PPE significantly increased headache severity and impaired task completion times compared to standard attire, while also raising heart rate and skin temperature, but reducing oxygen saturation levels.
- - Importantly, even though global cerebral blood flow remained unchanged, the use of PPE was linked to heightened headache scores and negative cerebral symptoms among participants.
Patient longevity and survival with custom-made endovascular solutions: The Fenestrated Anaconda approach.
Asian Cardiovasc Thorac Ann
September 2023
Article Synopsis
- Endovascular aortic repair (EVAR) is a key treatment for abdominal aortic aneurysms with good outcomes, but the Terumo Aortic Fenestrated Anaconda™ has shown particularly impressive results in minimizing complications and enhancing survival rates.
- A 9-year international study analyzed over 5,000 patients implanted with the Fenestrated Anaconda™, confirming 100% survival and target vessel patency in the first 6 years, though rates dropped after that.
- The study concluded that the Fenestrated Anaconda™ demonstrates exceptional effectiveness as an EVAR device, with very low instances of endograft migration or need for reintervention.
Article Synopsis
- A revolution in managing type B aortic dissection (TBAD) has occurred over the past 20 years, largely due to the introduction of thoracic endovascular aortic repair (TEVAR), though there are ongoing debates about its use, especially regarding differences between genders and ethnicities in outcomes.
- An international study examined data from 58 TBAD patients treated with TEVAR over 17 years, focusing on demographic and clinical outcome disparities between male and female patients of different ethnicities.
- Results indicated that while the mean age was similar, males had more complicated cases, larger proximal stent diameters, and most patients were Caucasian, highlighting a lack of significant ethnic diversity and no established risk prediction models.
Thoraflex Hybrid vs. AMDS: To replace the arch or to stent it in type A aortic dissection?
Asian Cardiovasc Thorac Ann
September 2023
Article Synopsis
- Acute type A aortic dissection (ATAAD) is a critical emergency requiring immediate surgery, with total arch replacement (TAR) and the frozen elephant trunk (FET) procedure being key treatments, notably using the Thoraflex Hybrid Prosthesis (THP).
- A review of clinical outcomes reveals that TAR with FET generally results in lower early mortality and better long-term survival compared to the Ascyrus Medical Dissection Stent (AMDS) used with hemi-arch replacement, though data on AMDS is limited.
- The conclusion emphasizes that while AMDS is a new option, THP through TAR with FET is currently the most effective and evidence-supported treatment for ATAAD.
Article Synopsis
- In the UK, two surgical approaches for repairing open abdominal aortic aneurysms (AAAs), transperitoneal (TP) and retroperitoneal (RP), were compared in patients with complex vascular issues.
- The study involved 57 patients, assessing outcomes like postoperative complications, hospital stay length, and systemic inflammation, with RP patients showing better results in these areas.
- Findings suggest that the RP approach, despite being more demanding, offers clinical advantages and cost savings, advocating for its more frequent use in complex AAA cases.
Article Synopsis
- Acute type B aortic dissection (TBAD) is rare, affecting up to 8 in 100,000 individuals yearly, and can lead to complications like organ malperfusion due to the unpredictable nature of the dissection.
- This study focuses on patients with TBAD who experienced organ malperfusion and were treated with thoracic endovascular aortic repair (TEVAR) at a single vascular unit over 16 years.
- Out of 28 TBAD patients, 25 underwent TEVAR, with 32% showing organ malperfusion symptoms; most had hypertension and upper/mid-thoracic pain, and the majority required additional surgical interventions.