Coronary artery spasm : role in acute myocardial ischaemia

Coronary artery spasm is an accepted cause of transient myocardial ischaemia in patients with variant angina. The electrocardiographic abnormality, ST segment elevation, which is a hallmark of this syndrome, resembles that seen experimentally when the animal coronary artery is ligated and clinically, when the human coronary artery is totally occluded by a balloon angioplasty catheter. Coronary artery spasm is defined as a severe localized constriction sufficiently profound to cause transient total or sub-total occlusion of an epicardial coronary artery resulting in myocardial ischaemia. Coronary artery spasm has also been suggested to play an important role in the pathophysiology of myocardial ischaemia throughout the wide clinical spectrum of coronary artery disease including effort angina, unstable angina, acute myocardial infarction and sudden death.peer-reviewe

Atrial fibrillation : a common arrhythmia with possible dire consequences

The diagnosis of atrial fibrillation (AF) is clinched on the electrocardiogram with the finding of fine baseline oscillations, absent P waves and irregular ventricular rhythm.1 It is the most common type of arrhythmia requiring medical care, with a prevalence of 1-2%.2 More than half of AF episodes are detected by continuous ambulatory ECG monitoring. Although uncommon in the younger age groups, less than 0.5% in 40-50 year olds, it affects 5-15% of the population by the age of 80 years.peer-reviewe

The long and winding road: the management of Acute Coronary Syndromes in Malta

The treatment of acute coronary syndromes in Malta has been revolutionized over the past decade by the introduction of the catheterization laboratory. With the set-up of on-call cardiac invasive teams for primary percutaneous coronary interventions in ST-elevation myocardial infarction, Malta may be counted among the elite cardiac centres. The recent completion of numerous multicentre international clinical trials has led to an upheaval in the strategy and armamentarium for the treatment of acute coronary syndromes.peer-reviewe

‘Twiddling’ of the pacemaker resulting in lead dislodgement

Twiddler’s syndrome is a rare condition in which patient manipulation of the pulse generator within its pocket may result in coiling of the lead and lead dislodgement, thereby causing pacemaker malfunction. Retraction of the electrode may cause phrenic nerve stimulation resulting in diaphragmatic stimulation and a sensation of abdominal pulsations. As the leads are further wrapped around the generator, rhythmic arm twitching may occur as a result of pacing of the brachial plexus.1 Twiddler’s syndrome was first described by Bayliss et al in 1968 as a complication of pacemaker implantation.2 It has also been reported with implantable cardioverter-defibrillators (ICDs)3 and cardiac resynchronisation therapy (CRT).4 This is a case report of an elderly lady with Twiddler’s syndrome resulting in pacemaker malfunction secondary to lead retraction, who emphatically denied any manipulation of her device. She subsequently underwent lead repositioning and appropriate counselling.peer-reviewe

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 7.8mmol/L (β=15.83, p=0005) 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.peer-reviewe

Transcatheter device closure of atrial septal defect and patent foramen ovale in Malta

Significant atrial septal defects (ASD) are closed, surgically or through a transcatheter device, in order to avoid pulmonary hypertension in late life. A patent foramen ovale (PFO) may need to be closed because of transient shunt reversal resulting in transient ischaemic events or stroke. We report the Maltese experience to date in transcatheter closure of these defects. A total of 46 ASDs and 51 PFOs have been successfully closed at our unit (total 97), with very low complication rates, rates that compare very favourably with results from larger international centres.peer-reviewe

Antiplatelet and anticoagulant therapy for non-ST-elevation acute coronary syndromes in a general hospital

Aim: To audit compliance with the 2011 European Society of Cardiology (ESC) guidelines for prescribing antiplatelet and anticoagulant therapy in patients diagnosed with non-ST-elevation acute coronary syndromes (NSTE-ACS). Methods: Five-month audit at Cardiac Catheterisation Suite, Mater Dei Hospital, Malta. A data collection form for inpatients diagnosed with NSTE-ACS was developed, psychometrically evaluated and completed for each patient by the investigator. Comparative analysis to assess whether these patients were being managed according to the guidelines was undertaken. Results: 165 patients were recruited; 73% were male, 37% were between 66 and 75 years and 44% were active smokers. The most common risk factors for cardiovascular disease in these patients were hypertension (27%), dyslipidemia and obesity (both 16%). 41% of the patients underwent a percutaneous coronary intervention, either ad hoc (34%) or elective (7%). Compliance to guidelines for prescription of aspirin and clopidogrel 300mg loading dose was 95% and 88% respectively. Compliance to guidelines for prescription of aspirin and clopidogrel 75mg daily maintenance dose was 97% and 96% respectively. Compliance to guidelines for prescription of proton pump inhibitors (PPIs) in patients receiving dual antiplatelet therapy (DAPT) was only 19%; 81% of the patients were prescribed omeprazole against guideline recommendations. Compliance to guidelines for prescription of anticoagulation therapy was 95% with respect to prescription of heparin treatment in combination with DAPT. Compliance to guidelines for prescription of enoxaparin was 81%. Compliance to guidelines for other antiplatelet and anticoagulant drugs recommended in the guidelines, including ticagrelor, prasugrel, glycoprotein IIb/IIIa receptor antagonists, fondaparinux and bivalirudin, was not measured. Conclusions: Prescription of antiplatelet and anticoagulant therapy for NSTE-ACS in Malta is predominantly in accordance with ESC guidelines. Alternative antiplatelet and anticoagulant drugs and PPIs should be included in the Maltese hospital formulary to improve NSTE-ACS management in line with guideline recommendations.peer-reviewe

Smoking ban : a long-term analysis of the Malta paradox in a population of over 400,000 subjects

Objectives: The introduction of laws that make indoor public areas and workplaces smoke-free has resulted in a significant reduction in the incidence of acute coronary syndromes (ACS). Malta was the second European country to introduce the smoking ban legislation in April 2004. The purpose of the study was to investigate the impact of the smoking ban in Malta on ACS morbidity and mortality. Methods: The number of ACS hospital admissions and the number of cardiovascular deaths were retrospectively analysed. The annual data for 5 years prior to and following the introduction of the Tobacco Act were obtained according to age-groups for both genders. Poisson regression analyses were performed to assess for decline in ACS admission and cardiovascular death. Results: The ACS admission rate increased throughout the 5 years following the introduction of the smoking ban. There was no change in mortality rate in the 5 years following the legislation, except in 2007 when a small but significant decline was noted. Conclusions: The Malta smoking ban did not have a significant impact on cardiovascular mortality and ACS admissions rates, indicating the need for proper enforcement of the public smoking ban and increase in public awareness regarding the adverse effects of smoking.peer-reviewe

CYP2C19 genetic polymorphisms in Maltese patients on clopidogrel therapy

Introduction and Aims: The prevalence of CYP2C19 genetic polymorphisms in the Maltese population is not reported. The aims were to determine CYP2C19 *2 and *17 allele frequencies and CYP2C19 genotype distribution in a cohort of Maltese patients on clopidogrel and to compare observed frequencies of the CYP2C19 *2 allele and *2/*2 genotype to other populations bordering the Mediterranean Sea. Methods: Genotyping for the CYP2C19 *2 and *17 alleles in Maltese patients on clopidogrel was performed using TaqMan® drug metabolism assays. The frequency of both alleles and six genotypes (*1/*1, *1/*2, *2/*2, *1/*17, *17/*17, *2/*17) were determined. Observed frequencies of the CYP2C19 *2 allele and *2/*2 genotype were compared to fourteen populations bordering the Mediterranean Sea (p>0.05 indicated similar prevalence) Results: Frequencies of the CYP2C19 *2 and *17 alleles in the 244 patients genotyped were 12.3% and 15.4% respectively. CYP2C19 genotype distribution was: *1/*1 (52.1%), *1/*17 (22.5%), *1/*2 (18.0%), 2/*17 (6.6%), *17/*17 (0.8%) and *2/*2 (0). Prevalence of the *2 allele in the Maltese cohort was similar to all fourteen populations bordering the Mediterranean Sea, while prevalence of *2/*2 was similar to Egyptian, Moroccan, Southern French, Slovenian, Turkish and Tunisian populations (p>0.05). Conclusions: This study provides an indication of the prevalence of CYP2C19 polymorphisms in Maltese patients. The high percentage of patients with CYP2C19 IM or UM phenotype demonstrates that CYP2C19 genotyping could aid clinicians to individualise treatment with clopidogrel and other drugs metabolised by the CYP2C19 enzyme.peer-reviewe

CYP2C19*2 allele carrier status and coronary in-stent restenosis : is there an association?

Background and objective: 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. Methods: Patients with previous PCI with stenting and who were scheduled for elective PCI after coronary angiogram were recruited from the cardiac catheterization suite over a 12-month period. The angiography report of each patient was perused to identify patients requiring PCI due to ISR. For patients with angiography-confirmed ISR, date of previous PCI to the restenosed stent was noted. CYP2C19*2 genotyping was undertaken using a TaqMan® Drug Metabolism assay. The association between CYP2C19*2 allele carrier status and incidence of coronary ISR within 1 year was assessed using Fisher’s exact test (p < 0.05 significance) and by calculating the odds ratio (OR) with a 95% confidence interval (CI). Results: Of the 82 patients with previous PCI, 29 (35.4%) had angiography-confirmed ISR (12 carriers, 17 noncarriers of CYP2C19*2). In 13 (44.8%) of these patients, the restenosed stent was deployed within 1 year and the patients were on clopidogrel therapy at the time of repeat PCI (8 carriers, 5 non-carriers of CYP2C19*2). The association between CYP2C19*2 allele carrier status and ISR within 1 year was not statistically significant (Fisher’s exact p = 0.067; OR: 4.80, 95% CI: 0.98–23.54, p = 0.053). Conclusions: Despite a higher proportion of CYP2C19*2 allele carriers exhibiting ISR within 1 year compared to non-carriers, the association was not statistically significant. This result may be attributed to the small sample size, and larger prospective studies are recommended to further assess this association.peer-reviewe