Robert G. Xuereb

A comparison between dual axis rotational coronary angiography and conventional coronary angiography

Background: Coronary angiography remains the gold standard for the investigation of coronary artery disease, and is carried out in multiple, predefined stationary views, at different angulations around the patient, for both left and right coronary arteries. Dual axis rotational coronary angiography (DARA) is an alternative technique wherein the c‐arm rotates around the patient in a preprogrammed single acquisition, exposing the entire coronary artery at different angulations. The DARA system has been recently installed in the Cardiac Catheterisation Suite at Mater Dei Hospital, Malta, where a monoplane and a biplane machine are available. This study was carried out in order to compare DARA with conventional single and biplane coronary imaging, with respect to radiation dose, contrast loads, and procedure time. Methods: This study was carried out over the period from September to December 2010. Four hundred sixty‐three patients were studied. Patients referred for the investigation of native coronary anatomy, for whatever indication, were consented and included, and randomly assigned to one of four groups depending on which machine and modality was used: monoplane conventional, monoplane DARA, biplane conventional, and biplane DARA. Results: DARA was statistically significantly superior in dose area product, fluoroscopy time, amount of contrast used, and procedure time. These reductions ranged between 12 (contrast used) and 71% (procedure time). Conclusions: The advantages of such systems are obvious to both patient and healthcare provider, and DARA may prove to be an important and useful tool in the refinement of diagnostic coronary angiography by reducing patient contrast and radiation doses and reducing procedure time.

Greater radiation savings at higher body mass indexes with dual axis rotational coronary angiography

In a recent article that compared monoplane conventional with monoplane dual-axis rotational (monoplane swing) angiography, and biplane conventional with biplane dual-axis rotational (biplane swing) angiography, we showed that dual axis rotational coronary angiography (DARA) was statistically significantly superior in dose area product (DAP), fluoroscopy time, amount of contrast used, and procedure time. These reductions

Non-Dipping Heart Rate and Microalbuminuria in Type 2 Diabetes Mellitus

Objectives: The aim of this study was to identify factors which are independently associated with non-dipping heart rate (HR) in a type 2 diabetic population at high risk of cardiovascular disease. Methods: The study recruited 179 type 2 diabetic subjects with a mean diabetes duration of 18.3 years and with proliferative retinopathy. All underwent 24-hour blood pressure and HR monitoring, and were assessed for markers of inflammation, insulin resistance, albuminuria, presence of peripheral neuropathy and peripheral vascular disease. Subjects whose night-time HR did not decrease by more than 10% as compared to daytime readings were classified as non-dippers. Results: Univariate analysis revealed that non-dippers had significantly higher logarithmic albumin-creatinine ratio (ACR; p = 0.001) and higher platelet count (p = 0.014). Also, non-dippers were more likely to be on β-blockers (p = 0.037). Binary logistic regression analysis showed that logarithmic ACR (p = 0.001) and platelet count (p = 0.026) were independent predictors of non-dipping HR, even when correcting for β-blocker use. Conclusions: In this high-risk type 2 diabetic population, non-dipping HR was independently associated with ACR and platelet count, suggesting that non-dipping HR might give an indication of underlying generalised atherosclerosis in diabetic patients. Also, non-dipping HR may represent a novel mechanism explaining the association of nephropathy with cardiovascular events. This merits further study.

Red blood cell distribution width and myocardial scar burden in coronary artery disease

Introduction Red blood cell distribution width (RDW) is a novel independent marker of cardiovascular disease including heart failure, coronary artery disease and myocardial ischaemia. The aim of the study was to investigate a possible relationship between RDW and myocardial scar burden, as assessed by a MIBI viability scan. A secondary objective was to assess whether there is an association between RDW and left ventricular ejection fraction (LVEF). Methods The study comprised 123 subjects with ischaemic heart disease who underwent a myocardial viability scan between June 2008 and July 2014. Haemoglobin, mean corpuscular volume, RDW, platelet count, mean platelet volume (MPV), estimated glomerular filtration rate, fasting blood glucose, liver and lipid profiles were evaluated for all patients. The extent of myocardial scarring and LVEF were noted. Data were analysed using IBM SPSS Statistics 22.0. Univariate followed by multivariate analyses were performed to assess for independent predictors of myocardial scarring and LVEF, respectively. Results The mean age of the study population was 63.5 years; most of the subjects were men. The median LVEF was 31% and median percentage of myocardial scarring was 8.7%. Multivariate analyses revealed that RDW, HDL-cholesterol and alanine transaminase were independent predictors of myocardial scarring while RDW, MPV, LDL-cholesterol and gamma-glutamyl transpeptidase were independent predictors of LVEF. Conclusions Increased RDW is an independent predictor both of myocardial scar burden and of impaired left ventricular function in subjects with coronary artery disease.

Female gender and cardiovascular disease

Despite a generalized belief that women are protected from cardiovascular disease, this remains the leading cause of death in women. This review focuses on differences in symptomatology, diagnostic modalities and therapeutic strategies in women with regard to cardiovascular disease.

CYP2C19*2 Allele Carrier Status and Coronary In-stent Restenosis: Is There an Association?

The CYP2C19*2 allele is associated with reduced clopidogrel bioactivation, increasing the risk of complications after percutaneous coronary intervention (PCI), particularly stent thrombosis. Recently published data suggests that CYP2C19*2 allele carriers have a higher risk for in-stent restenosis (ISR) after endovascular treatment. Very few studies have investigated the relationship between CYP2C19*2 and coronary ISR, with no significant association reported. The objective of this study was to assess the relationship between CYP2C19*2 allele carrier status and coronary ISR.

Relationship of Hyperglycaemia, Hypoglycaemia, and Glucose Variability to Atherosclerotic Disease in Type 2 Diabetes

Objective Type 2 diabetes mellitus (T2DM) is known to be associated with increased cardiovascular risk. The aim of this study was therefore to investigate the independent effects of hyperglycaemia, hypoglycaemia, and glucose variability on microvascular and macrovascular disease in T2DM. Methods Subjects with T2DM of <10 years duration and on stable antiglycaemic treatment underwent carotid intima-media thickness (CIMT), ankle-brachial index (ABI), albumin-creatinine ratio (ACR), and HbA1c measurement, as well as 72-hour continuous glucose monitoring. Macrovascular disease was defined as one or more of the following: history of ischaemic heart disease (IHD), cerebrovascular accident (CVA), ABI < 0.9, or abnormal CIMT. Results The study population comprised 121 subjects with T2DM (89 males : 32 females). The mean age was 62.6 years, and the mean DM duration was 3.7 years. Macrovascular disease was present in 71 patients (58.7%). In multivariate logistic regression analysis, body surface area (BSA) (OR 18.88 (95% CI 2.20–156.69), p = 0.006) and duration of blood glucose (BG) < 3.9 mmol/L (OR 1.12 (95% CI 1.014–1.228), p = 0.024) were independent predictors of macrovascular disease. BSA (OR 12.6 (95% CI 1.70–93.54), p = 0.013) and duration of BG < 3.9 mmol/L (OR 1.09 (95% CI 1.003–1.187), p = 0.041) were independent predictors of abnormal CIMT. Area under the curve for BG > 7.8 mmol/L (β = 15.83, p = 0.005) was the sole independent predictor of albuminuria in generalised linear regression. Conclusions This study demonstrates that hypoglycaemia is associated with the occurrence of atherosclerotic disease while hyperglycaemia is associated with microvascular disease in a Caucasian population with T2DM of recent duration.

PKP-007 Pharmacist led rapid point of care cytochrome p 2C19 genotyping for individualisation of antiplatelet therapy

Background The presence of the CYP2C19 loss of function *2 allele is associated with a decreased antiplatelet effect in clopidogrel treated patients. Since about 50% of major adverse cardiac events occur within the first 2 days post-percutaneous coronary intervention (PCI), a rapid CYP2C19*2 genotype result is important to individualise antiplatelet therapy at the start of treatment. Purpose To apply a pharmacist led process to individualise antiplatelet therapy guided by CYP2C19*2 genotyping using the rapid point of care (POC) Spartan RX assay (Spartan Bioscience) in patients undergoing PCI. Material and methods Following ethics approval and written informed consent, patients undergoing PCI with stent deployment for acute coronary syndrome or stable angina, and who were candidates for dual antiplatelet therapy, were recruited over a 3 month period by non-probability sampling. Exclusion criteria were patients <18 and >75 years old, body weight <60 kg, history of stroke or transient ischaemic attack, active bleeding, coagulation or platelet disorders, and/or chronic liver disease. A buccal sample was collected for automated CYP2C19*2 genotyping with the Spartan RX system within 1 h. Each patient was genotyped as a non-carrier of the *2 allele (*1/*1), a carrier of one *2 allele (*1/*2) or a carrier of two *2 alleles (*2/*2). Actionable genotypes (*1/*2, *2/*2) with therapy recommendations according to the 2013 Clinical Pharmacogenetics Implementation Consortium guidelines were communicated to the cardiologist. Results The patient cohort consisted of 34 patients. 25 patients were male and 9 were female, mean age was 66 years (range 49–75) and all patients were Caucasian. 21 patients were genotyped as non-carriers of the *2 allele, 12 patients were genotyped as carriers of one *2 allele and 1 patient was genotyped as a carrier of two *2 alleles. For the 13 patients with an actionable genotype, the pharmacist discussed choice of antiplatelet therapy with the cardiologist since they were candidates for an alternative to clopidogrel. Conclusion This POC assay was user friendly and rapidly identified carriers of the *2 allele. This study demonstrated the feasibility of this POC test to be implemented for pharmacist led CYP2C19*2 genotype guided individualisation of antiplatelet therapy during the critical period post-PCI. References and/or Acknowledgements University of Malta Faculty of Medicine and Surgery Dean’s Initiative, Technoline Ltd, Malta Heart Foundation, Orme Scientific Ltd No conflict of interest.