Assessing atrial myopathy with cardiac magnetic resonance imaging in embolic stroke of undetermined source.

Background: Left atrial myopathy has been implicated in atrial fibrillation (AF)-related stroke and embolic stroke of undetermined source (ESUS).

Objective: To use advanced cardiac magnetic resonance (CMR) imaging techniques, including left atrial (LA) strain and 4D flow CMR, to identify atrial myopathy in patients with ESUS.

Methods: 20 patients with ESUS and no AF or other cause for stroke, and 20 age and sex-matched controls underwent CMR with 4D flow analysis.

Too Little of a Good Thing: Strong Associations Between Cardiac Size and Fitness Among Women.

Background: Cardiorespiratory fitness (CRF) is associated with functional impairment and cardiac events, particularly heart failure (HF). However, the factors predisposing women to low CRF and HF remain unclear.

Objectives: This study sought to evaluate the association between CRF and measures of ventricular size and function and to examine the potential mechanism linking these factors.

Disease specific determinants of cardiopulmonary fitness in systemic sclerosis.

Objectives: We aimed to quantify the burden of exercise intolerance in systemic sclerosis (SSc) and explore the disease features that contribute to impaired exercise capacity (measured as peak oxygen uptake, peak VO) to provide novel mechanistic insights into the causes of physical disability in SSc.

Methods: Thirty-three SSc patients with no history of cardiac disease and no active myositis underwent cardiac and skeletal muscle MRI, transthoracic echocardiography, pulmonary function tests and cardiopulmonary exercise testing (CPET). CPET results were compared to an age-, sex-, and weight-matched controls with no overt cardiopulmonary disease.

Using magnetic resonance imaging to map the hidden burden of muscle involvement in systemic sclerosis.

Background: Skeletal muscle can be directly affected by systemic sclerosis (SSc); however, a significant burden of SSc-associated myopathy is undetected because clinical parameters such as weakness and creatine kinase (CK) are unreliable biomarkers of muscle involvement. This study presents qualitative and quantitative magnetic resonance imaging (MRI) findings that quantify the prevalence of myopathy and evaluate any association between skeletal and cardiac muscle involvement in SSc.

Methods: Thirty-two patients with SSc who fulfilled the 2013 American College of Rheumatology/European League Against Rheumatism classification criteria underwent skeletal muscle MRI in addition to cardiac MRI.

Myocardial fibrosis and arrhythmic burden in systemic sclerosis.

Objectives: Cardiac complications of SSc are a leading cause of SSc-associated death. Cardiac imaging for identifying substrate abnormality may be useful in predicting risk of cardiac arrhythmias or future cardiac failure. The aim of this study was to quantify the burden of asymptomatic fibro-inflammatory myocardial disease using cardiac magnetic resonance imaging (CMR) and assess the relationship between asymptomatic myocardial fibrosis and cardiac arrhythmias in SSc.

Left atrial, pulmonary vein, and left atrial appendage anatomy in Indigenous individuals: Implications for atrial fibrillation.

Background: Indigenous Australians experience a greater burden of AF. Whether this is in-part due to differences in arrhythmogenic structures that appear to contribute to AF differences amongst other ethnicities is not known.

Methods: We studied forty individuals matched for ethnicity and other AF risk factors.

Traditional markers of cardiac toxicity fail to detect marked reductions in cardiorespiratory fitness among cancer patients undergoing anti-cancer treatment.

Aims: Left ventricular ejection fraction (LVEF) is standard of care for evaluating chemotherapy-associated cardiotoxicity, although global longitudinal strain (GLS) offers advantages. However, neither change in LVEF or GLS has been associated with short-term symptoms, functional capacity, or long-term heart failure (HF) risk. We sought to determine whether an integrative measure of cardiovascular function (VO2peak) that is strongly associated with HF risk would be more sensitive to cardiac damage induced by cancer treatment than LVEF, GLS, or cardiac biomarkers.

Differentiating Nonischemic Dilated Cardiomyopathy With Incidental Infarction From Ischemic Cardiomyopathy by Geometric Indices Derived From Cardiovascular Magnetic Resonance.

Purpose: The purpose of this study was to differentiate nonischemic dilated cardiomyopathy with incidental myocardial infarction (NICM with incidental MI) from ischemic cardiomyopathy (ICM) by integrating left ventricular (LV) geometric indices and ischemic late gadolinium enhancement (LGE), obtained from cardiac magnetic resonance (CMR) imaging.

Materials And Methods: All subjects were studied on a 1.5 Tesla magnetic resonance imaging scanner.

Exercise cardiovascular magnetic resonance reveals reduced cardiac reserve in pediatric cancer survivors with impaired cardiopulmonary fitness.

Background: Pediatric cancer survivors are at increased risk of cardiac dysfunction and heart failure. Reduced peak oxygen consumption (peak VO) is associated with impaired cardiac reserve (defined as the increase in cardiac function from rest to peak exercise) and heart failure risk, but it is unclear whether this relationship exists in pediatric cancer survivors. This study sought to investigate the presence of reduced peak VO in pediatric cancer survivors with increased risk of heart failure, and to assess its relationship with resting cardiac function and cardiac haemodynamics and systolic function during exercise.

Clinical Utility of Stress Echocardiography in Remote Indigenous and Non-Indigenous Populations: A 10-Year Study in Central Australia.

Background: Remote Central Australia has a large Indigenous population and a significant burden of cardiovascular disease. Stress echocardiography has been previously validated as a useful investigation for long-term prognostication. However, there are no prior studies assessing its utility in remote or Indigenous populations.

Measuring atrial stasis during sinus rhythm in patients with paroxysmal atrial fibrillation using 4 Dimensional flow imaging: 4D flow imaging of atrial stasis.

Background: Paroxysmal atrial fibrillation (PAF) is associated with cardioembolic risk, however events may occur during sinus rhythm (SR). 4D-flow cardiac magnetic resonance (CMR) imaging allows visualisation of left atrial blood flow, to determine the residence time distribution (RTD), an assessment of atrial transit time.

Objective: To determine if atrial transit time is prolonged in PAF patients during SR, consistent with underlying atrial stasis.

Alcohol Abstinence in Drinkers with Atrial Fibrillation.

Background: Excessive alcohol consumption is associated with incident atrial fibrillation and adverse atrial remodeling; however, the effect of abstinence from alcohol on secondary prevention of atrial fibrillation is unclear.

Methods: We conducted a multicenter, prospective, open-label, randomized, controlled trial at six hospitals in Australia. Adults who consumed 10 or more standard drinks (with 1 standard drink containing approximately 12 g of pure alcohol) per week and who had paroxysmal or persistent atrial fibrillation in sinus rhythm at baseline were randomly assigned in a 1:1 ratio to either abstain from alcohol or continue their usual alcohol consumption.

Epicardial and subcutaneous adipose tissue in Indigenous and non-Indigenous individuals: Implications for cardiometabolic diseases.

Background: Obesity is prevalent in Indigenous populations who exhibit significant differences in body fat composition. While excess regional adiposity can be partially inferred from clinical measurements, noninvasive imaging allows for direct quantification of specific fat depots. Epicardial fat is a visceral adipose tissue that has been strongly associated with cardiometabolic disease in other populations.

Relation of Alcohol Consumption to Left Ventricular Fibrosis Using Cardiac Magnetic Resonance Imaging.

Light-to-moderate regular alcohol consumption has been associated with reduced mortality, heart failure, and sudden death, with a well described "U-shaped" relationship. We sought to determine whether markers of diffuse ventricular fibrosis as assessed by cardiac magnetic resonance imaging (CMR) T mapping differ between nondrinkers and regular drinkers. We prospectively recruited 165 participants to undergo 3T CMR ventricular T1 mapping which included 120 regular light-to-moderate drinkers (7 to 28 standard drinks per week for >12 months) and 45 age and gender-matched nondrinking controls (1 standard drink ∼12 g alcohol).

Regular Alcohol Consumption Is Associated With Impaired Atrial Mechanical Function in the Atrial Fibrillation Population: A Cross-Sectional MRI-Based Study.

Objectives: This study sought to determine the impact of regular alcohol consumption on left atrial (LA) mechanical and reservoir function.

Background: Earlier studies suggest that regular alcohol intake is associated with increased atrial fibrillation (AF) and LA dilatation.

Methods: This study prospectively enrolled 160 patients with paroxysmal or persistent AF to undergo 3-T cardiac magnetic resonance (CMR) imaging in sinus rhythm.

Reduction in mortality from implantable cardioverter-defibrillators in non-ischaemic cardiomyopathy patients is dependent on the presence of left ventricular scar.

Aims: In patients with non-ischaemic cardiomyopathy (NICM), the mortality benefit of a primary prevention implantable cardioverter-defibrillator (ICD) has been challenged. Left ventricular (LV) scar identified by cardiac magnetic resonance (CMR) imaging is associated with a high risk of malignant arrhythmia in NICM. We aimed to determine the impact of LV scar on the mortality benefit from a primary prevention ICD in NICM.

The ventricular residence time distribution derived from 4D flow particle tracing: a novel marker of myocardial dysfunction.

4D flow cardiac magnetic resonance (CMR) imaging allows visualisation of blood flow in the cardiac chambers and great vessels. Post processing of the flow data allows determination of the residence time distribution (RTD), a novel means of assessing ventricular function, potentially providing additional information beyond ejection fraction. We evaluated the RTD measurement of efficiency of left and right ventricular (LV and RV) blood flow.

Absence of late gadolinium enhancement on cardiac magnetic resonance imaging in ventricular fibrillation and nonischemic cardiomyopathy.

Introduction: Cardiac magnetic resonance (CMR)-identified late gadolinium enhancement (LGE), representing regional fibrosis, is often used to predict ventricular arrhythmia risk in nonischemic cardiomyopathy (NICM). However, LGE is more closely correlated with sustained monomorphic ventricular tachycardia (SMVT) than ventricular fibrillation (VF). We characterized CMR findings of ventricular LGE in VF survivors.

Comparison of Magnetic Resonance Analysis of Myocardial Scarring With Biomarker Release Following S-T Elevation Myocardial Infarction.

Background: Late gadolinium enhancement (LGE) with cardiac magnetic resonance (CMR) is commonly assumed to represent myocardial fibrosis; however, comparative human histological data are limited, and there is no consensus on the most accurate method for LGE quantitation. We evaluated the relationship between CMR assessment of regional fibrosis and infarct size assessment using serial biomarkers after ST elevation acute myocardial infarction (STEMI).

Methods: Ninety-three patients treated for STEMI (59±10 years, 86% male) underwent CMR 6 months after infarction.

SASHA versus ShMOLLI: a comparison of T1 mapping methods in health and dilated cardiomyopathy at 3 T.

Cardiac Magnetic Resonance derived T1 mapping parameters are a non-invasive method of estimating diffuse myocardial fibrosis. This study aims to to determine the native T1 time, post contrast T1 time and extracellular volume (ECV) derived from T1 mapping and to evaluate the ability of T1 mapping techniques to discriminate healthy myocardium from dilated cardiomyopathy. Seventy-nine participants underwent cardiac magnetic resonance imaging at the Baker Heart and Diabetes Institute, Melbourne, Australia.