Genetic factors related to aspirin resistance using the Multiplate® device in Hong Kong Chinese patients with stable coronary heart disease.

Objective: Associations between single nucleotide polymorphisms (SNPs) and aspirin resistance (AR) have been studied with variable results. The associations of genetic variants with AR may be helpful to explain why some individuals demonstrate aspirin insensitivity with this anti-platelet therapy. The purpose of this research was to investigate the effect of different genotypes in candidate genes on aspirin response in patients taking long-term aspirin therapy by measuring the serum thromboxane B2 (TXB2) and platelet function using the Multiplate® analyser. Methods: A total of 266 patients with stable coronary heart disease (CHD) taking low-dose aspirin for long periods of time and without any other anti-platelet drugs medications were enrolled into the study. They were required to take 80 mg of aspirin every morning for a week including the day before blood tests. Blood samples were collected 24 h after the last dose. The 80 mg dose of aspirin was taken orally and blood samples were collected again 1 h later. The serum TXB2 levels were measured in samples at 24 h post-dose and 1 h post-dose using the EIA kit and platelet activity was determined using the Multiplate® Impedance Platelet Aggregometry (ASPI) assay. Genotyping assays were performed by the TaqMan SNP genotyping technique. Results: Of the 266 patients, only 251 patients were enrolled in the present study. The PTGS1/COX1-1676 A > G (rs1330344) and the PTGS2/COX2-765 G > C (rs20417) SNPs showed significant associations with the ASPI measurements in samples taken at 24 h post-dose, but not with the values at 1 h post-dose or with the TXB2 levels (P < 0.05). Conclusions: Our results suggest that polymorphisms in the PTGS1/COX1 and the PTGS2/COX2 genes may be associated with reduced anti-aggregatory effects and increased the risk of AR, but future larger-scale cohort studies are necessary for further validation.

BIOSOLVE-IV-registry: Safety and performance of the Magmaris scaffold: 12-month outcomes of the first cohort of 1,075 patients.

OBJECTIVES: We aimed to assess the safety and performance of the Magmaris sirolimus-eluting bioresorbable magnesium scaffold in a large patient population. BACKGROUND: Magmaris has shown good outcomes in small-sized controlled trials, but further data are needed to confirm its usability, safety, and performance. METHODS: BIOSOLVE-IV is an international, single arm, multicenter registry including patients with a maximum of two single de novo lesions. Follow-up is scheduled up to 5 years; the primary outcome is target lesion failure (TLF) at 12 months. RESULTS: A total of 1,075 patients with 1,121 lesions were enrolled. Mean patient age was 61.3 ± 10.5 years and 19.2% (n = 206) presented with non-ST-elevation myocardial infarction (NSTEMI). Lesions were 3.2 ± 0.3 mm in diameter and 14.9 ± 4.2 mm long; 5.1% (n = 57) were bifurcation lesions. Device success was 97.3% (n = 1,129) and procedure success 98.9% (n = 1,063). The Kaplan-Meier estimate of TLF at 12 months was 4.3% [95% confidence interval, CI: 3.2, 5.7] consisting of 3.9% target lesion revascularizations, 0.2% cardiac death, and 1.1% target-vessel myocardial infarction. Definite/probable scaffold thrombosis occurred in five patients (0.5% [95% CI: 0.2, 1.1]), thereof four after early discontinuation of antiplatelet/anticoagulation therapy. CONCLUSION: BIOSOLVE-IV confirms the safety and performance of the Magmaris scaffold in a large population with excellent device and procedure success and a very good safety profile up to 12 months in a low-risk population.

A new treatment paradigm for phlegmasia cerulea dolen: Single stage endovascular pharmacomechanical thrombectomy with venoplasty and stenting.

BACKGROUND: Phlegmasia Cerulae Dolen (PCD) is potentially a lethal disease but there is currently no established treatment algorithm for it. The aim of this study was to assess the safety and effectiveness of single stage endovascular pharmacomechanical thrombectomy with venoplasty and stenting in the treatment of PCD. METHOD: This was a retrospective single centre observational study of consecutive patients who underwent endovascular intervention for the treatment of PCD between June 2016 and March 2020. Clinical and procedural details were recorded. Procedural and clinical success rate, procedural complications, and 30 days mortality were reported. RESULT: 11 patients were treated during the study period. 2 (18.2%) had active malignancy. 63.6% were uncomplicated PCD on presentation. Common iliac vein compression or stenosis were demonstrated in all patients. Venous stents were implanted in all cases and procedures were successful in all cases. All patients had symptoms improvement at 72 hours post procedure. Other than 2 major bleeding complications, there was no other adverse event. The 30 days mortality was 18.2%. Active malignancy and the presence of anaemia were significantly associated with major complications. CONCLUSION: Single stage endovascular thrombectomy and stenting was effective and safe in the treatment of patients with PCD. Common Iliac vein compression was a common underlying cause of PCD.

Trends of prescribing adherence of antiplatelet agents in Hong Kong patients with acute coronary syndrome: a 10-year retrospective observational cohort study.

OBJECTIVES: The objective of this study is to examine the temporal trend of antiplatelet prescribing pattern during index hospitalisation discharge in Hong Kong (HK) acute coronary syndrome (ACS) population. DESIGN: The study is a retrospective observational cohort study. SETTING: The study retrieved data from electronic health record from Hospital Authority (HA), HK. PARTICIPANTS: The study included patients aged 18 years old or above, who were admitted to seven institutions under HA with diagnosis of ACS during 2008-2017. PRIMARY AND SECONDARY OUTCOME MEASURES: The primary outcome was the frequency of antiplatelet therapy prescription at the point of index hospitalisation discharge each year during 2008-2017. Association between demographics, baseline comorbidities, procedures and antiplatelet prescription were examined as secondary outcome using multivariate logistic regression model, with commonly used antiplatelet groups selected for comparison. RESULTS: Among the included 14 716 patients, 5888 (40.0%) discharged with aspirin alone, 6888 (46.8%) discharged with dual antiplatelet therapy (DAPT) with clopidogrel, and 973 (6.6%) discharged with DAPT with prasugrel/ticagrelor. Prescribing rate of aspirin alone decreased substantially from 56.8% in 2008 to 27.5% in 2017. Utilisation of DAPT with clopidogrel increased from 33.7% in 2008 to 52.7% in 2017. Use of DAPT with prasugrel/ticagrelor increased from 0.3% in 2010 to 15.3% in 2017. Compared with those prescribed with DAPT with clopidogrel, male patients (adjusted OR (aOR) 1.34, 95% CI 1.09 to 1.65), patients with non-ST-elevation myocardial infarction (aOR 2.50, 1.98 to 3.16) or ST-elevation myocardial infarction (aOR 3.26, 2.59 to 4.09), use of glycoprotein IIb/IIIa (aOR 3.03, 2.48 to 3.68) or undergoing percutaneous coronary intervention (aOR 3.85, 3.24 to 4.58) or coronary artery bypass graft (aOR 6.52, 4.63 to 9.18) during index hospitalisation, concurrent use of histamine-2 receptor antagonists (aOR 1.35, 1.10 to 1.65) or proton pump inhibitors (aOR 3.57, 2.93 to 4.36) during index hospitalisation discharge were more likely to be prescribed with DAPT with prasugrel/ticagrelor. Patients with older age (aOR 0.97, 0.96 to 0.97), diabetes (aOR 0.68, 0.52 to 0.88), chronic kidney disease (aOR 0.43, 0.22 to 0.85) or concurrent use of oral anticoagulant (aOR 0.16, 0.07 to 0.42) were more likely to received DAPT with clopidogrel. CONCLUSIONS: Use of DAPT with prasugrel/ticagrelor was suboptimal yet improving during 2008-2017 in HK patients with ACS. Considering DAPT, predictors for clopidogrel prescription, compared with prasugrel/ticagrelor, were consistent with identified risk factors of bleeding.

Descriptive analysis of real-world medication use pattern of statins and antiplatelet agents among patients with acute coronary syndrome in Hong Kong and the USA.

OBJECTIVES: The objective was to explore the differences in medication use pattern of lipid-lowering drug (LLD) and antiplatelet agents among post-percutaneous coronary intervention patients with acute coronary syndrome aged <65 in Hong Kong (HK) and the USA. DESIGN: Retrospective study. SETTING: This study used deidentified claims data from Clinformatics Data Mart database (OptumInsight, Eden Prairie, Minnesota, USA) and electronic health records from HK Hospital Authority Clinical Data Analysis and Reporting System database. PARTICIPANTS: We used 1 year prescription records of LLDs and antiplatelet agents among 1013 USA patients and 270 HK Chinese patients in 2011-2013. PRIMARY AND SECONDARY OUTCOME MEASURES: Continuity was investigated on the assumption that one defined daily dose represented 1 day treatment. Medication possession ratio method was used to evaluate the adherence. Multivariate-adjusted logistic regressions were constructed to compare the good continuity and adherence levels in the merged database with the cutoffs set at 80%, and Cox proportional hazard models were built using the time to discontinuation as the dependent variable, to assess the persistence level. RESULTS: HK Chinese patients were less adherent (67.41% vs 84.60%, adjusted odds ratio (AOR) for Americans over Chinese=2.23 (95% CI=1.60 to 3.12), p<0.001) to antiplatelet agents compared with American patients but better adherent to statins (90.00% vs 78.18%, AOR=0.37 (0.23 to 0.58), p<0.001). The discontinuation with statins was more common in American patients (13.33% vs 34.25%, adjusted hazard ratio (AHR)=2.95 (2.05 to 4.24), p<0.001). Low-to-moderate potency statins and clopidogrel were favoured by our HK local physicians, while American patients received higher doses of statins and prasugrel. CONCLUSIONS: We seemed to find HK physicians tended to prescribe cheaper and lower doses of statins and antiplatelet agents when compared with the privately insured patients in the USA, though the adherence and persistence levels of HK patients with statins were relatively good.

Atrial dysfunction and interatrial dyssynchrony predict atrial high rate episodes: insight into the distinct effects of right atrial appendage pacing.

INTRODUCTION: Right atrial (RA) appendage pacing may prolong atrial conduction time (ACT). This study aimed to investigate if RA appendage pacing can induce intra- and interatrial dyssynchrony and if atrial dysfunction and dyssynchrony can predict atrial high rate episodes (AHREs) in the first year after pacing. METHODS AND RESULTS: Patients implanted with dual-chamber pacemakers for symptomatic bradycardia were enrolled. Cumulative percentage of RA appendage pacing (Cum%AP) during 1-year follow-up and AHREs were recorded. Full Doppler echocardiography studies were performed before implantation and 1 year after pacing. ACT and peak atrial velocities (Sm-la, Em-la, Am-la) were measured. One hundred ten patients (age 70.5 ± 11 years; 53 males) were recruited and completed 1-year follow-up. ACT of both RA and left atrial (LA) were more prolonged in patients with Cum%AP > 75% than those with <25%. Intra- and interatrial dyssynchrony was more obvious in patients with Cum%AP > 75% (22.3 ± 12.2 milliseconds vs 9.5 ± 6.2 milliseconds; 53.9 ± 29.7 milliseconds vs 19.7 ± 17.3 milliseconds; both P < 0.001). AHREs occurred in 29% of patients. Atrial pump function and interatrial dyssynchrony independently predicted AHREs in multivariate analysis. Receiver operating characteristic curve provided a cutoff value of Am-la <5.3 cm/s, which predicted AHREs with a sensitivity of 71% and a specificity of 75% (area under the curve, 0.822; P < 0.001). CONCLUSION: RA appendage pacing causes atrial conduction delay with intra- and interatrial dyssynchrony. Atrial dysfunction and interatrial dyssynchrony are related to AHREs in the first year after pacing.