Long-term durability of self-expanding and balloon-expandable transcatheter aortic valve prostheses: UK TAVI registry.

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. Patients with paired echocardiograms postprocedure and ≥5-years post-TAVI were included. Severe SVD was determined according to European task force guidelines. RESULTS: 221 patients (79.4 ± 7.3 years; 53% male) were included with median echocardiographic follow-up 7.0 years (range 5-13 years). Follow-up exceeded 10 years in 43 patients (19.5%). Valve types were the supra-annular self-expanding CoreValve (SEV; n = 143, 67%), balloon-expandable SAPIEN/XT (BEV; n = 67, 31%), Portico (n = 4, 5%) and unknown (n = 7, 3%). There was no difference between postprocedure and follow-up peak gradient in the overall cohort (19.3 vs. 18.4 mmHg; p = NS) or in those with ≥10-years follow-up (21.1 vs. 21.1 mmHg; p = NS). Severe SVD occurred in 13 patients (5.9%; median 7.8-years post-TAVI). Three cases (23.1%) were due to regurgitation and 10 (76.9%) to stenosis. Valve-related reintervention/death occurred in 5 patients (2.3%). Severe SVD was more frequent with BEV than SEV (11.9% vs. 3.5%; p = 0.02), driven by a difference in patients treated with small valves (BEV 28.6% vs. SEV 3.0%; p < 0.01). CONCLUSIONS: Hemodynamic function of transcatheter heart valves remains stable up to more than 10 years post-TAVI. Severe SVD occurred in 5.9%, and valve-related death/reintervention in 2.3%. Severe SVD was more common with BEV than SEV.

The impact of learning-curve-experience on transcatheter aortic valve replacement outcomes: Insights from the United Kingdom and Ireland all-comers second-generation ACURATE neo™ transcatheter aortic heart valve registry.

BACKGROUND: The ACURATE neo™ is a novel, second-generation self-expanding supra-annular transcatheter heart valve (THV). The objective of this multi-centre registry is to assess the safety, clinical utility, and impact of 'learning-curve-experience' (LCE) on transcatheter aortic valve replacement outcomes in the United Kingdom (UK) and Ireland. METHODS: We prospectively collected data from seven ACURATE neo™ THV implanting centres (n = 484) between February 2016 and November 2020. We compared mortality rates and outcomes in the LCE group (n = 120) compared to next successive 120 cases. RESULTS: The mean age of the cohort was 81.9(SD: 6.1) years and the majority were in the moderate risk category (EuroSCORE-II):3.3(SD: 3). The 97.5% of cases were performed under local anesthetic. The valve was successfully deployed in 98.8% of cases. The survival rate at 30 days was 97.9%. The incidence of stroke was 2.5%. Life threatening bleeding occurred in 0.6% of cases and vascular access complications occurred in 21 (4.3%) patients. Implantation-related conduction abnormalities occurred in 8.3% but only 5.6% required a PPM. The successful valve deployment occurred in 96% of the patients in the LCE group compared to 100% in the other group (p = 0.04; OR-2[CI 1.7-2.3]). The mortality rates at 30 days (1.7% vs. 1.7%) and 1 year (1.9% vs. 2.7%) were comparable between the two groups. CONCLUSIONS: This study represents the largest published UK and Ireland real-world experience of the ACURATE neo™ valve. The procedural success rates and safety outcomes were excellent and endorse its utility in clinical practice. The LCE appears to have an impact on the successful valve deployment but without translating into short-term or long-term outcomes.

Safety and efficacy of interrupting dual antiplatelet therapy one month following percutaneous coronary intervention: a meta-analysis of randomized controlled trials.

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. All randomised controlled trials (RCTs) investigating one-month versus routine duration of DAPT in patients undergoing PCI and reporting outcomes from the time of cessation of DAPT (1 month) to 1 year were eligible for inclusion in the meta-analysis. The pooled risk ratios (RR) with their 95% confidence interval (CI) were calculated with the random-effects model using the Mantel-Haenszel method. Four RCTs involving 26,576 patients were included in this meta-analysis. Cessation of DAPT after 1 month was associated with significantly less major bleeding [RR 0.70, 95%CI (0.51-0.95), P = 0.02, heterogeneity (I2) = 42%]. There was no statistically significant difference in all-cause mortality [RR 0.84 (95%CI 0.69-1.03), P = 0.10, I2 = 0%] and stroke [RR 0.71 (95%CI 0.45-1.13), P = 0.15, I2 = 42%] when compared to routine duration of DAPT. There was also no difference in myocardial infarction (MI) [RR 1.12 (95%CI 0.91-1.39), P = 0.28, I2 = 0%], and definite or probable stent thrombosis [RR 1.49 (95%CI 0.92-2.41), P = 0.11, I2 = 0%] with cessation of DAPT after 1 month. Cessation of DAPT 1 month after PCI was associated with significantly less major bleeding, but there was no difference in the rate of all-cause mortality, stroke, MI and stent thrombosis.

Comparison of Self-Expanding Bioprostheses for Transcatheter Aortic Valve Replacement in Patients With Symptomatic Severe Aortic Stenosis: SCOPE 2 Randomized Clinical Trial.

BACKGROUND: Few randomized trials have compared bioprostheses for transcatheter aortic valve replacement, and no trials have compared bioprostheses with supra-annular design. The SCOPE 2 trial (Safety and Efficacy Comparison of Two TAVI Systems in a Prospective Randomized Evaluation 2) was designed to compare the clinical outcomes of the ACURATE neo and CoreValve Evolut bioprostheses for transcatheter aortic valve replacement. METHODS: SCOPE 2 was a randomized trial performed at 23 centers in 6 countries between April 2017 and April 2019. Patients ≥75 years old with an indication for transfemoral transcatheter aortic valve replacement as agreed by the heart team were randomly assigned to receive treatment with either the ACURATE neo (n=398) or the CoreValve Evolut bioprostheses (n=398). The primary end point, powered for noninferiority of the ACURATE neo bioprosthesis, was all-cause death or stroke at 1 year. The key secondary end point, powered for superiority of the ACURATE neo bioprosthesis, was new permanent pacemaker implantation at 30 days. RESULTS: Among 796 randomized patients (mean age, 83.2±4.3 years; mean Society of Thoracic Surgeons Predicted Risk of Mortality score, 4.6±2.9%), clinical follow-up information was available for 778 (98%) patients. Within 1 year, the primary end point occurred in 15.8% of patients in the ACURATE neo group and in 13.9% of patients in the CoreValve Evolut group (absolute risk difference, 1.8%, upper 1-sided 95% confidence limit, 6.1%; P=0.0549 for noninferiority). The 30-day rates of new permanent pacemaker implantation were 10.5% in the ACURATE neo group and 18.0% in the CoreValve Evolut group (absolute risk difference, -7.5% [95% CI, -12.4 to -2.60]; P=0.0027). No significant differences were observed in the components of the primary end point. Cardiac death at 30 days (2.8% versus 0.8%; P=0.03) and 1 year (8.4% versus 3.9%; P=0.01), and moderate or severe aortic regurgitation at 30 days (10% versus 3%; P=0.002) were significantly increased in the ACURATE neo group. CONCLUSIONS: Transfemoral transcatheter aortic valve replacement with the self-expanding ACURATE neo did not meet noninferiority compared with the self-expanding CoreValve Evolut in terms of all-cause death or stroke at 1 year, and it was associated with a lower incidence of new permanent pacemaker implantation. In secondary analyses, the ACURATE neo was associated with more moderate or severe aortic regurgitation at 30 days and cardiac death at 30 days and 1 year. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03192813.

Initial experience of a self-expanding transcatheter aortic valve with an outer pericardial wrap: The United Kingdom and Ireland Implanters' registry.

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. The primary efficacy outcome was the Valve Academic Research Consortium-2 (VARC-2)-defined endpoint of device success. The primary safety outcome was the VARC-2-defined composite endpoint of early safety at 30 days. RESULTS: A total of 317 patients underwent implantation. Mean age was 81.8 ± 6.4 years and Society of Thoracic Surgeons Predicted Risk of Mortality Score 5.5 ± 1.8%. Iliofemoral access was used in 99.1% of patients. Device success was 91.2%. Mean gradient was 7.6 ± 4.7 mmHg and effective orifice area 1.9 ± 0.7 cm2 . The incidence of moderate paravalvular regurgitation was 1.7% and there was no severe paravalvular regurgitation. A new permanent pacemaker was implanted in 17.8% of patients without a pacemaker at baseline. Early safety was demonstrated in 92.7%. At 30 days, all-cause mortality was 0.6%, stroke 3.8%, and major vascular complication 2.8%. CONCLUSIONS: Real-world experience of the Evolut PRO transcatheter aortic valve demonstrated favorable procedural success, safety, valve function, and incidence of new permanent pacemaker implantation.

Initial experience of a large, self-expanding, and fully recapturable transcatheter aortic valve: The UK & Ireland Implanters' registry.

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. The primary efficacy outcome was the Valve Academic Research Consortium-2(VARC-2)-defined endpoint of device success. The primary safety outcome was the VARC-2-defined composite endpoint of early safety at 30 days. RESULTS: A total of 217 patients underwent attempted implant. Mean age was 79.5 ± 8.8 years and Society of Thoracic Surgeons Predicted Risk of Mortality Score 5.2% ± 3.4%. Iliofemoral access was used in 91.2% of patients. Device success was 79.7%. Mean gradient was 7.0 ± 4.6 mmHg and effective orifice area 2.0 ± 0.6 cm2 . Paravalvular regurgitation was more than mild in 7.2%. A new permanent pacemaker was implanted in 15.7%. Early safety was demonstrated in 91.2%. At 30 days, all-cause mortality was 3.2%, stroke 3.7%, and major vascular complication 2.3%. CONCLUSIONS: Real-world experience of the 34 mm Evolut R transcatheter aortic valve demonstrated acceptable procedural success, safety, valve function, and incidence of new permanent pacemaker implantation.

Microvascular dysfunction in the immediate aftermath of chronic total coronary occlusion recanalization.

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. METHODS: After successful CTO PCI in 21 consecutive patients, coronary pressure and flow velocity were measured at baseline and hyperemia in distal segments of the CTO/target vessel and an unobstructed reference vessel. Hemodynamics including hyperemic microvascular resistance (HMR), basal microvascular resistance (BMR), and instantaneous minimal microvascular resistance at baseline and hyperemia were calculated and compared between reference and target/CTO vessels. RESULTS: After CTO PCI, BMR was reduced in the target/CTO vessel compared with the reference vessel: 3.58 mm Hg/cm/s vs 4.94 mm Hg/cm/s, difference -1.36 mm Hg/cm/s (-2.33 to -0.39, p = 0.008). We did not detect a difference in HMR: 1.82 mm Hg/cm/s vs 2.01 mm Hg/cm/s, difference -0.20 (-0.78 to 0.39, p = 0.49). Instantaneous minimal microvascular resistance correlated strongly with the length of stented segment at baseline (r = 0.63, p = 0.005) and hyperemia (r = 0.68, p = 0.002). CONCLUSIONS: BMR is reduced in a recanalized CTO in the immediate aftermath of PCI compared to an unobstructed reference vessel; however, HMR appears to be preserved. A longer stented segment is associated with increased microvascular resistance. © 2016 Wiley Periodicals, Inc.

Chromosome 16q22 variants in a region associated with cardiovascular phenotypes correlate with ZFHX3 expression in a transcript-specific manner.

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. ZFHX3 has two main transcripts that utilise different transcription start sites. We examined the association between genetic variants in the 16q22.3 region and expression of ZFHX3 to identify variants that regulate gene expression. RESULTS: We genotyped 65 single-nucleotide polymorphisms to tag genetic variation at the ZFHX3 locus in two cohorts, 451 British individuals recruited in the North East of England and 310 mixed-ancestry individuals recruited in South Africa. Allelic expression analysis revealed that the minor (A) allele of rs8060701, a variant in the first intron of ZFHX3, was associated with a 1.16-fold decrease in allelic expression of both transcripts together, (p = 4.87e-06). The minor (C) allele of a transcribed variant, rs10852515, in the second exon of ZFHX3 isoform A was independently associated with a 1.36-fold decrease in allelic expression of ZFHX3 A (p = 7.06e-31), but not overall ZFHX3 expression. However, analysis of total gene expression of ZFHX3 failed to detect an association with genotype at any variant. Differences in linkage disequilibrium between the two populations allowed fine-mapping of the locus to a 7 kb region overlapping exon 2 of ZFHX3 A. We did not find any association between ZFHX3 expression and any of the variants identified by genome wide association studies. CONCLUSIONS: ZFHX3 transcription is regulated in a transcript-specific fashion by independent cis-acting transcribed polymorphisms. Our results demonstrate the power of allelic expression analysis and trans-ethnic fine mapping to identify transcript-specific cis-acting regulatory elements.

Safety and feasibility of early discharge after transcatheter aortic valve implantation with ACURATE Neo-the POLESTAR trial.

BACKGROUND: Transcatheter aortic valve implantation (TAVI) serves a growing range of patients with severe aortic stenosis (AS). TAVI has evolved to a streamlined procedure minimizing length of hospital stay. AIMS: To evaluate the safety and efficacy of an early discharge (ED) strategy after TAVI. METHODS: We performed an international, multi-center, prospective observational single-arm study in AS patients undergoing TAVI with the ACURATE valve platform. Eligibility for ED was assessed prior to TAVI and based on prespecified selection criteria. Discharge ≤ 48 h was defined as ED. Primary Valve Academic Research Consortium (VARC)-3-defined 30-day safety and efficacy composite endpoints were landmarked at 48 h and compared between ED and non-ED groups. RESULTS: A total of 252 patients were included. The median age was 82 [25th-75th percentile, 78-85] years and the median Society of Thoracic Surgeons Predicted Risk of Mortality (STS-PROM) score was 2.2% [25th-75th percentile, 1.6-3.3]. ED and non-ED were achieved in 173 (69%) and 79 (31%) patients respectively. Monitoring for conduction disturbances was the principal reason for non-ED (33%). Overall, at 30 days, all-cause mortality was 1%, new permanent pacemaker rate was 4%, and valve- or procedure-related rehospitalization was 4%. There was no difference in the primary safety and efficacy endpoint between the ED and non-ED cohorts (OR 0.84 [25th-75th percentile, 0.31-2.26], p = 0.73, and OR 0.97 [25th-75th percentile, 0.46-2.06], p = 0.94). The need for rehospitalization was similarly low for ED and non-ED groups. CONCLUSION: Early discharge after TAVI with the ACURATE valve is safe and feasible in selected patients. Rhythm monitoring and extended clinical observation protracted hospital stay.

Chromosome 9p21 SNPs Associated with Multiple Disease Phenotypes Correlate with ANRIL Expression.

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. Total expression of the three genes was correlated (P<0.05), suggesting that they are co-regulated. SNP associations mapped by allelic and total expression were similar (r = 0.97, P = 4.8x10(-99)), but the power to detect effects was greater for allelic expression. The proportion of expression variance attributable to cis-acting effects was 8% for CDKN2A, 5% for CDKN2B, and 20% for ANRIL. SNP associations were similar in the two populations (r = 0.94, P = 10(-72)). Multiple SNPs were independently associated with expression of each gene (P<0.05 after correction for multiple testing), suggesting that several sites may modulate disease susceptibility. Individual SNPs correlated with changes in expression up to 1.4-fold for CDKN2A, 1.3-fold for CDKN2B, and 2-fold for ANRIL. Risk SNPs for coronary disease, stroke, diabetes, melanoma, and glioma were all associated with allelic expression of ANRIL (all P<0.05 after correction for multiple testing), while association with the other two genes was only detectable for some risk SNPs. SNPs had an inverse effect on ANRIL and CDKN2B expression, supporting a role of antisense transcription in CDKN2B regulation. Our study suggests that modulation of ANRIL expression mediates susceptibility to several important human diseases.

Permanent pacemaker implantation and left bundle branch block with self-expanding valves - a SCOPE 2 subanalysis.

BACKGROUND: No detailed data on left bundle branch block (LBBB) and permanent pacemaker implantation (PPI) exist from randomised clinical trials comparing the ACURATE neo and CoreValve Evolut devices. AIMS: Our aim was to assess the incidence and impact of new LBBB and PPI with self-expanding prostheses from a powered randomised comparison. METHODS: From the SCOPE 2 trial, 648 patients with no previous pacemaker were analysed for PPI at 30 days, and 426 patients without previous LBBB were adopted for analysis of LBBB at 30 days.  Results: At 30 days, 16.5% of patients required PPI; rates were higher in CoreValve Evolut compared to ACURATE neo recipients (21.0% vs 12.3%; p=0.004). Previous right bundle branch block (odds ratio [OR] 6.11, 95% confidence interval [CI]: 3.19-11.73; p<0.001) was associated with an increased risk of PPI at 30 days, whereas the use of the ACURATE neo (OR 0.50, 95% CI: 0.31-0.81; p=0.005) was associated with a decreased risk. One-year mortality was similar in patients with and without new PPI. A total of 9.4% of patients developed persistent LBBB at 30 days, with higher incidences in CoreValve Evolut recipients (13.4% vs 5.5%; p=0.007). New LBBB at 30 days was associated with lower ejection fraction at 1 year (65.7%±11.0 vs 69.1%±7.6; p=0.041). CONCLUSIONS: New LBBB and PPI rates were lower in ACURATE neo compared to CoreValve Evolut recipients. The ACURATE neo valve was associated with a lower risk of PPI at 30 days. No effect on 1-year mortality was determined for PPI at 30 days, while LBBB at 30 days was associated with reduced ejection fraction at 1 year.

GuideLiner, a child-in-a-mother catheter for successful retrieval of an entrapped rotablator burr.

Entrapment of the rotablator burr within heavily calcified lesions is a recognized complication, which usually necessitates sternotomy and open surgical intervention to retrieve the trapped burr. In some cases, the trapped burr can be retrieved using simple traction, but this is potentially hazardous with possible trauma and perforation of the vessel. Passing a wire alongside the trapped burr with ballooning to free the burr can be attempted. We describe a novel technique to remove a trapped rotablator burr from a heavily calcified lesion using counter-traction with a GuideLiner, child-in-a-mother catheter, which successfully removed the entrapped burr without the need for surgery when simple traction alone had been ineffective.

Bleeding risk differences after TAVR according to the ARC-HBR criteria: insights from SCOPE 2.

BACKGROUND: The Academic Research Consortium - High Bleeding Risk (ARC-HBR) initiative defined conditions associated with percutaneous coronary intervention (PCI)-related bleeding. AIMS: We sought to further explore these HBR conditions in the setting of transcatheter aortic valve replacement (TAVR). METHODS: Patients from the SCOPE 2 trial were stratified by their bleeding risk status based on the ARC-HBR definitions. Baseline and procedural characteristics, as well as key clinical outcomes including Bleeding Academic Research Consortium (BARC) 3-5 bleeding, were compared in ARC-HBR positive (HBR+) and ARC-HBR negative (HBR-) patients. RESULTS: Of 787 patients randomised in SCOPE 2 and included in this study, 633 were HBR+ (80.4%). Compared with HBR- patients, those HBR+ were older and more frequently presented with diabetes, a history of coronary artery disease, atrial fibrillation, prior cerebrovascular accident, and a Society of Thoracic Surgeons predicted risk of 30-day mortality (STS-PROM) (4.9±2.9% vs 3.3%±2.1%; p<0.0001). In addition, HBR+ patients were more frequently on oral anticoagulation therapy. At 1 year, HBR+ patients had higher rates of all-cause death (12.4% vs 4.3%, respectively, risk difference 8.09%; 95% confidence interval [CI]: 3.76-12.41; p=0.0002); the rates of BARC 3-5 type bleeding were relatively high but not statistically different compared with HBR- patients (7.7% vs 6.1%, risk difference 1.67%; 95% CI: -2.72 to 6.06; p=0.46). Subgroup analyses for bleeding events showed no significant interaction in terms of STS-PROM score, age, or medications. CONCLUSIONS: The ARC-HBR criteria failed to isolate a subgroup of patients at higher bleeding risk in TAVR patients from a randomised trial. These findings have potential implications, especially for the selection of post-TAVR antithrombotic regimens based on individual bleeding-risk profiles. Specific HBR criteria should be defined for TAVR patients.

Rationale and Design of the Project to Look for Early Discharge in Patients Undergoing TAVR With ACURATE (POLESTAR Trial).

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. STUDY DESIGN: The POLESTAR trial is an international, multi-center, prospective, observational study which aims to evaluate the safety of early discharge in selected patients who undergo TAVR with the supra-annular functioning self-expanding ACURATE Neo transcatheter heart valve (THV). A total of 250 patients will be included based on a set of baseline criteria indicating potential early discharge (within 48 h post-TAVR). Primary study endpoints include Valve Academic Research Consortium (VARC)-3 defined safety at 30 days and VARC-3 defined efficacy at 30 days and 1 year. Endpoints will be compared between early discharge and non-early discharge cohorts with a distinct landmark analysis at 48 h post-TAVR. Secondary endpoints include quality of life assessed using EQ5D-5L and Kansas City Cardiomyopathy Questionnaire (KCCQ) questionnaires and resource costs compared between discharge groups. SUMMARY: The POLESTAR trial prospectively evaluates safety and feasibility of an early discharge protocol for TAVR using the ACURATE Neo THV.

Genetic mechanisms mediating atherosclerosis susceptibility at the chromosome 9p21 locus.

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. This suggests that the effect of the 9p21 locus on atherosclerotic risk is mediated via a hitherto unknown pathway potentially amenable to therapeutic modulation. Investigation of potential disease mechanisms at this locus is therefore a focus of intense interest. In this review, we discuss the progress that has been made in the study of mechanisms and highlight the outstanding research questions.

A cohort study examining urgent and emergency treatment for decompensated severe aortic stenosis.

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. Primary endpoints were 30-day and 1-year mortality. RESULTS: Fifty-two patients underwent urgent or emergency BAV and 87 underwent TAVI. Baseline characteristics of the two groups were well matched. Significant differences were noted between the two groups in 30-day all-cause mortality (88.5% BAV patients alive at 30 days, 97.7% TAVI patients; P < 0.05) and 1-year all-cause mortality (44.2% BAV patients alive at 1 year, 88.5% TAVI patients; P < 0.001). At 1 year, the estimated hazard ratio for patients undergoing BAV was 11.2 (95% confidence interval: 4.67-26.9; P < 0.001) when adjusted for potential confounding variables. Patients in the BAV group who successfully underwent subsequent TAVI or SAVR all survived for 365 days, but there was no significant 1-year mortality difference compared with those who underwent urgent or emergency TAVI (100 vs. 88.5%; P > 0.155). CONCLUSION: Our results suggest treatment of decompensated severe aortic stenosis with urgent or emergency TAVI may be associated with improved survival outcomes when compared with a strategy of performing BAV as a bridge to subsequent TAVI or SAVR.

MLH1 Differential allelic expression in mutation carriers and controls.

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. In patients and controls, we show that allelic expression imbalance (AEI) can be readily detected in RNA extracted from whole blood from patients carrying mutations expected to elicit NMD using mass spectrometry. Mutations closer to the 5' end of the gene tend to show smaller imbalances. AEI can also be detected in normal controls. Analysis of allelic expression in controls and individuals with mutations not expected to exhibit NMD revealed that MLH1 expression is influenced by sequence variation acting in cis. A maximum likelihood framework was used to identify two SNPs, rs1799977 (c.655G>A; p.I219V) and rs1800734 (c.-93 G>A) that are independently associated with expression. These influences are, however, small compared to the differences associated with pathological variants.

Untreatable Severe Structural Degeneration of a Transcatheter Aortic Heart Valve.

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.

No-reflow phenomenon and comparison to the normal-flow population postprimary percutaneous coronary intervention for ST elevation myocardial infarction: case-control study (NORM PPCI).

INTRODUCTION: No-reflow (NR) phenomenon is characterised by the failure of myocardial reperfusion despite the absence of mechanical coronary obstruction. NR negatively affects patient outcomes, emphasising the importance of prediction and management. The objective was to evaluate the incidence and independent predictors of NR in patients presenting with ST-elevation myocardial infarction (STEMI). METHODS: This was a single-centre prospective case-control study. Cases were subjects who suffered NR, and the control comparators were those who did not. Clinical outcomes were documented. Salient variables relating to the patients and their presentation, history and angiographical findings were compared using one-way analysis of variance or χ2 test. Multiple regression determined the independent predictors, and a risk score was established based on the ß coefficient. RESULTS: Of 173 consecutive patients, 24 (13.9%) suffered from NR, with 46% occurring post stent implantation. Patients with NR had increased risk of in-hospital death (OR 7.0, 95% CI 1.3 to 36.7, p=0.022). From baseline variables available prior to percutaneous coronary intervention, the independent predictors of NR were increased lesion complexity, admission systolic hypertension, weight of <78 kg and history of hypertension. Continuous data were transformed into best-fit binary variables, and a risk score was defined. Significant difference was demonstrated between the risk score of patients with NR (4.1±1) compared with controls (2.6±1) (p<0.001), and the risk score was considered a good test (area under the curve=0.823). A score of ≥4 had 75% sensitivity and 76.5% specificity. CONCLUSION: Patients with NR have a higher rate of mortality following STEMI. Predictors of NR include lesion complexity, systolic hypertension and low weight. Further validation of this risk model is required.

STK39 polymorphisms and blood pressure: an association study in British Caucasians and assessment of cis-acting influences on gene expression.

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. We determined whether reported SNPs influenced STK39 expression in vivo, or were associated with BP in a large British Caucasian cohort. METHODS: 1372 members of 247 Caucasian families ascertained through a hypertensive proband were genotyped for reported risk variants in STK39 (rs6749447, rs3754777, rs35929607) using Sequenom technology. MERLIN software was used for family-based association testing. Cis-acting influences on expression were assessed in vivo using allelic expression ratios in cDNA from peripheral blood cells in 35 South African individuals heterozygous for a transcribed SNP in STK39 (rs1061471) and quantified by mass spectrometry (Sequenom). RESULTS: No significant association was seen between the SNPs tested and systolic or diastolic BP in clinic or ambulatory measurements (all p > 0.05). The tested SNPs were all associated with allelic expression differences in peripheral blood cells (p < 0.05), with the most significant association for the intronic SNP rs6749447 (P = 9.9 x 10-4). In individuals who were heterozygous for this SNP, on average the G allele showed 13% overexpression compared to the T allele. CONCLUSIONS: STK39 expression is modified by polymorphisms acting in cis and the typed SNPs are associated with allelic expression of this gene, but there is no evidence for an association with BP in a British Caucasian cohort.