Heart, Lung and Circulation

Editorial Board

2012-02-01

Population Screening An Important Step In Identifying And Increasing Awareness Of Cardiovascular Disease In Developing Countries

2012-02-01

When Oral Anticoagulation Therapy is Needed in Patients With Cardiomyopathies: A Review of Literature

2012-02-01

The question whether to anticoagulate patients with cardiomyopathy or not is over 50years old. Multiple clinical trials have demonstrated the superior therapeutic effect of warfarin compared with placebo in the prevention of thromboembolic events amongst patients with nonvalvular atrial fibrillation. The purpose of our work is to review literature about the role of anticoagulation in the main cardiomyopathies.

Cardiac Computed Tomography—Evidence, Limitations and Clinical Application

Christian R. Hamilton-Craig, Daniel Friedman, Stephan Achenbach — 2012-02-01

Coronary CT angiography and coronary calcium scoring offer a new approach to the diagnosis of coronary artery disease (CAD). They hold significant promise in improving patient outcomes, through identification of atherosclerosis and improved risk assessment.Coronary calcium scoring has proven predictive value concerning the occurrence of future cardiovascular events and outperforms current risk evaluation methods such as the Framingham Risk Score.Coronary CT angiography allows visualisation of the coronary artery lumen, detection of stenoses as well as visualisation of both calcified and non-calcified plaque.The accuracy of coronary CT angiography to detect obstructive coronary artery disease has been established by numerous trials. In particular the negative predictive value of the test approaches 100% in low and intermediate risk groups.Outcomes data demonstrate significant prognostic ability of coronary CT angiography.Modern techniques allow substantial reduction of dose values and radiation exposure of coronary CT angiography has significantly fallen. Coronary CT angiography can be reliably performed with doses similar to the level of annual background radiation, and less than one-third of a Tc Sestamibi scan.Coronary CT angiography has been approved for Medicare reimbursement for specific indications when performed by accredited providers.High quality examinations, experience and careful patient selection and preparation are required to ensure optimal results of coronary CT angiography, and to guide clinical decisions.

Lipid Management in High Risk Coronary Patients: How Effective are We at Secondary Intervention?

2012-02-01

Objective: To assess the proportion of patients who achieve and maintain target lipid levels during optimum long term follow up after coronary bypass surgery.Methods: From a prospectively compiled database, we identified 440 patients followed for up to 13 years after CABG as part of a radial artery randomised controlled trial. All available lipid assays conducted during the follow-up period were collected from pathology databases. These were used to calculate the annualised mean lipid exposure for each patient. Based upon National Heart Foundation guidelines, we determined the proportion of patients whose mean lipid exposure attained target levels (total cholesterol<4.0mmol/L, LDL-C<2.0mmol/L, HDL-C>1.0mmol/L and triglycerides<1.5mmol/L). This was compared with the proportion who had achieved these targets pre-operatively and on their most recent cholesterol measurement.Results: 6077 lipid studies (total cholesterol, LDL, HDL and triglycerides) in total were obtained. In those who had baseline data available, target levels for total cholesterol, HDL-C, LDL-C and triglycerides were attained pre-operatively by 16%, 64%, 14% and 39% of patients respectively. Annualised mean lipid exposures during up to 13 years of follow up for all patients revealed somewhat improved but still suboptimal target attainment figures of 24%, 83%, 20% and 53%. The most recent review shows the greatest improvement at 47%, 68%, 43% and 62% respectively. Of 141 diabetic patients, target attainment was significantly higher for total cholesterol (31%; p=0.038) and LDL-C (28%; p=0.006) but lower for HDL-C (75%; p=0.002) and triglycerides (40%; p<0.001).Conclusion: Despite some improvements seen over careful follow up, only HDL-C targets appear attainable for the majority of CABG patients. Over half still do not achieve non-HDL national lipid targets.

N-terminal Prohormone B-type Natriuretic Peptide and Cardiovascular Function in Africans and Caucasians: The SAfrEIC Study

2012-02-01

Background: This study compared NT-proBNP levels and the association with cardiovascular markers between Africans and Caucasians from South Africa.Methods: This cross-sectional study involved 201 Africans and 255 Caucasians from the North West province, South Africa. Serum NT-proBNP concentrations, blood pressure, pulse wave velocity and arterial compliance were measured.Results: NT-proBNP levels were significantly higher (P<0.001) in Africans than Caucasians, also after adjusting for gender, body mass index (BMI) and pulse wave velocity (P=0.008). This significant difference became borderline significant after adjusting for systolic blood pressure (SBP) (P=0.060), and non-significant after adjusting for arterial compliance (P=0.35). In single regression, a significant positive correlation of NT-proBNP with SBP (r=0.26; P<0.001) and pulse pressure (PP) (r=0.28; P<0.001) were shown for Africans only. After multiple adjustments, the associations of NT-proBNP with SBP and PP remained significant in Africans (SBP: β=0.187, P<0.01; PP: β=0.234, P<0.001), with no significant associations in Caucasians.Conclusions: NT-proBNP levels were higher in Africans than Caucasians, independently of BMI and gender. This difference was partly driven by higher SBP and lower arterial compliance in Africans. NT-proBNP was persistently associated with SBP and PP in Africans, but not in Caucasians. These associations may suggest early vascular changes contributing to cardiac alterations in Africans.

Guidelines for the diagnosis and management of Catecholaminergic Polymorphic Ventricular Tachycardia

Andreas Pflaumer, Andrew M. Davis — 2012-02-01

Background: Catecholaminergic Polymorphic Ventricular Tachycardia (CPVT) is an inherited arrhythmia syndrome, characterised by polymorphic ventricular tachycardia induced by adrenergic stress. CPVT can be caused by mutations the cardiac ryanodine receptor gene (RYR2) or mutations in the cardiac calsequestrin gene CASQ2. Structural heart disease is usually absent and the baseline ECG is usually normal. Patients with CPVT often present with exercise- or emotion induced syncope, the first presentation can also be sudden cardiac death.Management: Besides removal of triggers treatment with beta blockers is currently a class I indication in clinically diagnosed patients. Beta blockage should be titrated up to an effective level. The addition of flecainide seems to be a promising approach in patients where arrhythmias are not completely suppressed by beta blockers. A cardioverter-defibrillator (ICD) or left cervical sympathetic denervation might be considered under special circumstances. Genetic counselling is recommended and all first degree relatives should be properly evaluated.

Short Term Outcomes after Cardiac Surgery in a Jehovah's Witness Population: An Institutional Experience

L. Marshall, C. Krampl, M. Vrtik, B. Haluska, R. Griffin, J. Mundy, P. Shah — 2012-02-01

Background: Minimising blood transfusion has a number of medical and logistical benefits, and is of particular importance for followers of the Jehovah's Witness faith. We examined the short term outcomes in this group of patients based on our institutional practice over the past decade.Patients/methods: Data on 59 patients (73% male, mean age 66 years [range 40–83]) who identified as Jehovah's Witness was prospectively collected and retrospectively analysed from a systematised database over the period from January 1999 to June 2010. Mean logistic Euroscore was 4.5, with coronary artery bypass procedures most common (44/59, 75%) followed by aortic valve replacement (6/59, 10%).Results: Average haemoglobin (Hb) fell from 142g/L preoperatively to 109g/L at discharge. Output from cardiac drains was reduced in patients who received aprotinin (34/59, 58%, p=0.05) compared to tranexaemic acid (11/59, 18%) or no antifibrinolytic (15/59, 25%). Operative mortality was 1/59 (1.7%) with an average length of postoperative stay of 6.2 days. Morbidity rates for neurologic deficit 2/59 (3.4%), deep sternal infection 1/59 (1.7%) and postoperative myocardial infarction 1/59 (1.7%) were within accepted ranges.Conclusion: Cardiac surgery can be performed safely in Jehovah's Witness patients with acceptable outcomes.

A Rare Case of Penetrating Atherosclerotic Ulcer of the Aorta

Fei Chong, Matthew Winter, Philip Puckridge, Amy Penhall, Majo Joseph — 2011-10-17

We are reporting a case of 66 year-old man who presented to a regional hospital with sudden onset of inter-scapular pain, radiating to anterior chest. Initial assessment was unremarkable except for high blood pressure and computed tomography (CT) of chest showing an intramural haematoma in the thoracic descending aorta. He was transferred to our institution for the medical management of his blood pressure and intramural haematoma of the aorta. A transoesophageal echocardiography confirmed the diagnosis but in addition demonstrated a penetrating atherosclerotic ulcer (PAU). Subsequently CT aortogram revealed a slow leak from the PAU. Endovascular repair with stent-grafting was urgently performed. He improved clinically and remained well on discharge. This case demonstrated that PAU, although rare and often under-recognised, is potentially life-threatening and should be considered in the evaluation of chest pain. Multi-modality imaging techniques can aid the diagnosis and guide appropriate and timely management.

Approach to the Difficult Transseptal: Diathermy Facilitated Left Atrial Access

Hany S. Abed, Muayad Alasady, Dennis H. Lau, Han S. Lim, Prashanthan Sanders — 2011-10-17

Percutaneous transseptal left atrial (LA) access is increasingly becoming a routine procedure in the electrophysiology and cardiac catheterisation laboratories. Our aim was to review an unselected large series of this procedure performed over a period of five years. We clinically characterised difficult cases and presented a method of safe and expeditious LA access. Overall, 543 transseptal punctures were performed. Of those, 10 were classified as difficult, with failure to access the LA in three or more attempts. In all 10 cases, surgical electrocautery was successfully used to facilitate needle puncture of the septum. All patients subsequently underwent an uncomplicated procedure. In conclusion, we describe a method to trouble-shoot the difficult transseptal access procedure, outlining the clinical characteristics, echocardiographic features and special precautions that need to be considered when utilising this method.

Multivessel Coronary Artery Spasm

2011-10-17

Coronary spasm is increasingly recognised as an important aetiological mechanism causing myocardial ischaemia. Occasionally cases present with evidence of ST segment elevation myocardial infarction, usually secondary to spasm confined to a solitary coronary artery. We present the rare and life-threatening case of severe coronary spasm afflicting all three major epicardial arteries simultaneously. It describes the difficult emergency scenario and ongoing management dilemmas encountered by physicians confronted with multivessel coronary spasm. Moreover we discuss the malignant prognosis associated with this ailment and describe the potential insights provided by cardiac magnetic resonance imaging that might identify those at greatest risk after the index event.

Inversion of the Left Atrial Appendage: A Complication of Cardiac Surgery

Gemma S. Smiles, Rahul Basu, Ian M. Mitchell — 2011-10-17

An inverted left atrial appendage which fails to revert spontaneously is a rare complication of cardiac surgery. We present a case of an inverted left atrial appendage discovered intraoperatively on transoesophageal echocardiography. This was readily identified and was easily corrected with digital manipulation. Intraoperative transoesophageal echocardiography plus an awareness of the possibility that a newly presenting left atrial mass post-bypass might be an inverted left atrial appendage, facilitates immediate correction. So doing removes any need for further investigation or further cardiac surgery and reduces the risk of a subsequent thromboembolic event if the diagnosis is not made until later.

Porcelain Aorta, Left Arterio-Venous Fistula and Critical Ostial Coronary Artery Disease

2011-10-17

Dabigatran for patients with a mechanical valve

Frans Van de Werf, John Eikelboom — 2012-02-01

We read with great interest the case report by Stewart et al. , describing a 62 year-old Caucasian patient who suffered thrombosis of a mechanical aortic valve and an embolic stroke whilst being treated for more than eight months with dabigatran (150mg b.i.d.) and 100mg aspirin. Dabigatran etexilate is a new oral direct thrombin inhibitor currently approved for the prevention of stroke and systemic embolism in patients with non-valvular atrial fibrillation. In the RELY study , a dose of 150mg b.i.d. was shown to be associated with a significantly lower risk of stroke and systemic embolism with a similar risk of major bleeding when compared with warfarin.

Re: Letter responding to “Dabigatran for patients with a mechanical valve – by F. Van de Werf and J. Eikelboom”

Ralph Stewart, Heather Astell, Laura Young, Harvey D. White — 2012-02-01

We thank Drs Van De Werf and Eikelboom for drawing attention to the potential for differences in renal function to influence the efficacy as well as safety of dabigatran. Our patient suffered thrombosis on a St Jude aortic valve whilst taking dabigatran 150mgbd and aspirin 100mg daily. His calculated serum creatinine clearance was 66ml/min/1.73m2, which is similar to the average creatinine clearance of patients who participated in the RELY trial . It is therefore unlikely plasma levels of dabigatran were lower than expected because of good renal function.

Heart Foundation

2012-02-01

The Cardiac Society of Australia and New Zealand

2012-02-01

Instructions to Authors

2012-02-01