Publications by authors named "Michael S Cunnington"

Background: With expansion of transcatheter aortic valve implantation (TAVI) into younger patients, valve durability is critically important.

Aims: We aimed to evaluate long-term valve function and incidence of severe structural valve deterioration (SVD) among patients ≥ 10-years post-TAVI and with echocardiographic follow-up at least 5-years postprocedure.

Methods: Data on patients who underwent TAVI from 2007 to 2011 were obtained from the UK TAVI registry.

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Very short duration of dual antiplatelet therapy (DAPT) following percutaneous coronary intervention (PCI) has recently attracted a lot of attention with the introduction of newer generations stents. This is appealing, especially in patients at high bleeding risk. However, none of the trials were powered for the individual ischemic and bleeding endpoints.

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Background: Transcatheter aortic valve replacement (TAVR) is now an established treatment strategy for elderly patients with symptomatic aortic stenosis (AS) across the entire operative risk spectrum. Streamlined TAVR protocols along with reduced procedure time and expedited ambulation promote early hospital discharge. Selection of patients suitable for safe early discharge after TAVR might improve healthcare efficiency.

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Aims: We compared strategies in the treatment of decompensated severe aortic stenosis. The hypothesis was that undertaking urgent or emergency transcatheter aortic valve implantation (TAVI) directly in such patients is safer and more effective than urgent or emergency balloon aortic valvuloplasty (BAV) followed by elective TAVI or surgical aortic valve replacement (SAVR).

Methods: This was a single-centre retrospective study including all consecutive patients who underwent urgent or emergency BAV or TAVI for decompensated severe aortic stenosis between September 2014 and February 2018.

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We describe a patient who presented with heart failure 7 years post-transcatheter aortic valve implantation (TAVI) as a result of severe structural valve degeneration. Anatomic challenges, combined with the type of transcatheter heart valve used initially, meant that TAVI-in-TAVI risked obstructing the coronary arteries, even if preceded by bioprosthetic aortic scallop intentional laceration to prevent iatrogenic coronary artery obstruction. The patient was treated with balloon aortic valvuloplasty.

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Objectives: The United Kingdom and Ireland Implanters' registry is a multicenter registry which reports on real-world experience with new transcatheter heart valves.

Background: The Evolut PRO (Medtronic, Minneapolis, MN) transcatheter aortic valve is a self-expanding transcatheter aortic valve with an outer pericardial wrap, designed to minimize paravalvular regurgitation.

Methods: Between July 2017 and December 2018, clinical, procedural, and 30-day outcome data were prospectively collected from all patients receiving the Evolut PRO valve across nine participating centers in the United Kingdom and Ireland.

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Background: Very little is known about long-term valve durability after transcatheter aortic valve replacement (TAVR).

Objectives: This study sought to evaluate the incidence of structural valve degeneration (SVD) 5 to 10 years post-procedure.

Methods: Demographic, procedural, and in-hospital outcome data on patients who underwent TAVR from 2007 to 2011 were obtained from the U.

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Objectives: The UK & Ireland Implanters' registry is a multicenter registry which reports on real-world experience with novel transcatheter heart valves.

Background: The 34 mm Evolut R transcatheter aortic valve is a self-expanding and fully recapturable transcatheter aortic valve, designed to treat patients with a large aortic annulus.

Methods: Between January 2017 and April 2018, clinical, procedural and 30-day outcome data were prospectively collected from all patients receiving the 34 mm Evolut R valve across 17 participating centers in the United Kingdom and Ireland.

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Cardiogoniometry (CGM) is method of 3-dimensional electrocardiographic assessment which has been shown to identify patients with angiographically defined, stable coronary artery disease (CAD). However, angiographic evidence of CAD, does not always correlate to physiologically significant disease. The aim of our study was to assess the ability of CGM to detect physiologically significant coronary stenosis defined by fractional flow reserve (FFR).

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Objectives: In the presence of a chronically occluded coronary artery, the collateral circulation matures by a process of arteriogenesis; however, there is considerable variation between individuals in the functional capacity of that collateral network. This could be explained by differences in endothelial health and function. We aimed to examine the relationship between the functional extent of collateralization and levels of biomarkers that have been shown to relate to endothelial health.

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Objectives: The aim of this study was to compare microvascular resistance under both baseline and hyperemic conditions immediately after percutaneous coronary intervention (PCI) of a chronic total occlusion (CTO) with an unobstructed reference vessel in the same patient

Background: Microvascular dysfunction has been reported to be prevalent immediately after CTO PCI. However, previous studies have not made comparison with a reference vessel. Patients with a CTO may have global microvascular and/or endothelial dysfunction, making comparison with established normal values misleading.

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Background: The presence of a concomitant chronic total coronary occlusion (CTO) and a large collateral contribution might alter the fractional flow reserve (FFR) of an interrogated vessel, rendering the FFR unreliable at predicting ischemia should the CTO vessel be revascularized and potentially affecting the decision on optimal revascularization strategy. We tested the hypothesis that donor vessel FFR would significantly change after percutaneous coronary intervention of a concomitant CTO.

Methods And Results: In consecutive patients undergoing percutaneous coronary intervention of a CTO, coronary pressure and flow velocity were measured at baseline and hyperemia in proximal and distal segments of both nontarget vessels, before and after percutaneous coronary intervention.

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Background: The ZFHX3 gene, located in Chromosome 16q22.3, codes for a transcription factor which is widely expressed in human tissues. Genome-wide studies have identified associations between variants within the gene and Kawasaki disease and atrial fibrillation.

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Background: Significant paravalvular aortic regurgitation (PAR) after transcatheter aortic valve implantation (TAVI) is associated with negative clinical consequences. We hypothesize that increased eccentricity of the aortic annulus is associated with greater PAR.

Methods: Patients with severe aortic stenosis underwent multidetector computed tomography (MDCT) before successful TAVI with the Medtronic CoreValve bioprosthesis.

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Background: The high diagnostic accuracy of adenosine stress cardiac magnetic resonance (AS-CMR) for detecting coronary artery stenoses, with high sensitivity and specificity, is well documented. Prognostic data, particularly in non-low risk study populations and for greater than 12 months of follow up, is however lacking or variable in its findings. We present prognostic data, in an intermediate cardiovascular risk cohort undergoing adenosine stress perfusion CMR, over approximately 2 years of follow up.

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Accurate assessment of aortic annular dimensions is essential for successful transcatheter aortic valve implantation (TAVI). Annular dimensions are conventionally measured in mid-systole by multidetector computed tomography (MDCT), echocardiography and angiography. Significant differences in systolic and diastolic aortic annular dimensions have been demonstrated in cohorts without aortic stenosis (AS), but it is unknown whether similar dynamic variation in annular dimensions exists in patients with severe calcific AS in whom aortic compliance is likely to be substantially reduced.

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Recent genome-wide association studies have demonstrated that common genetic variants in a region of chromosome 9p21 confer risk of coronary artery disease (CAD) and other atherosclerotic conditions. Although the absolute increase in risk is small (some 20-30% increase in risk of CAD per copy of the deleterious alleles), the common occurrence of the variants means that their effect on the population risk of disease is estimated to be substantial. Studies investigating the relationship between risk variants and both "classical" and "emerging" atherosclerotic risk factors have found no evidence of association.

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Germline defects in the MLH1 gene are associated with Lynch syndrome. A substantial proportion of these mutations leads to premature termination codons and can induce nonsense mediated decay (NMD) of the corresponding transcript. Resulting allelic expression differences represent a fast and inexpensive method to identify patients carrying MLH1 mutations.

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Single nucleotide polymorphisms (SNPs) on chromosome 9p21 are associated with coronary artery disease, diabetes, and multiple cancers. Risk SNPs are mainly non-coding, suggesting that they influence expression and may act in cis. We examined the association between 56 SNPs in this region and peripheral blood expression of the three nearest genes CDKN2A, CDKN2B, and ANRIL using total and allelic expression in two populations of healthy volunteers: 177 British Caucasians and 310 mixed-ancestry South Africans.

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Background: Blood pressure (BP) has significant heritability, but the genes responsible remain largely unknown. Single nucleotide polymorphisms (SNPs) at the STK39 locus were recently associated with hypertension by genome-wide association in an Amish population; in vitro data from transient transfection experiments using reporter constructs suggested that altered STK39 expression might mediate the effect. However, other large studies have not implicated STK39 in hypertension.

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