Showing papers in "Heart Lung and Circulation in 2019"
TL;DR: Understanding of SCD is improving through greater knowledge of clinical risk factors, cardiomyopathies, and primary arrhythmic disorders, but data from other global regions and particularly from low-and middle-income countries remains scarce.
Abstract: Despite advancements in prevention and treatment, sudden cardiac death (SCD) remains a leading cause of mortality and is responsible for approximately half of all deaths from cardiovascular disease. Outcomes continue to remain poor following a sudden cardiac arrest, with most individuals not surviving. Although coronary heart disease remains the dominant underlying condition, our understanding of SCD is improving through greater knowledge of clinical risk factors, cardiomyopathies, and primary arrhythmic disorders. However, despite a growing wealth of information from studies in North America, Europe, and Japan, data from other global regions (and particularly from low-and middle-income countries) remains scarce.
252 citations
TL;DR: Genetics, cellular mechanisms, risk stratification and treatments for long QT syndrome, Brugada syndrome and CPVT are summarized, and flecainide is remarkably effective in CPVT.
Abstract: Forty per cent (40%) of sudden unexpected natural deaths in people under 35 years of age are associated with a negative autopsy, and the cardiac ion channelopathies are the prime suspects in such cases. Long QT syndrome (LQTS), Brugada syndrome (BrS) and catecholaminergic polymorphic ventricular tachycardia (CPVT) are the most commonly identified with genetic testing. The cellular action potential driving the heart cycle is shaped by a specific series of depolarising and repolarising ion currents mediated by ion channels. Alterations in any of these currents, and in the availability of intracellular free calcium, leaves the myocardium vulnerable to polymorphic ventricular tachycardia or ventricular fibrillation. Each channelopathy has its own electrocardiogram (ECG) signature, typical mode of presentation, and most commonly related gene. Long QT type 1 (gene, KCNQ1) and CPVT (gene, RyR2) typically present with cardiac events (ie syncope or cardiac arrest) during or immediately after exercise in young males; long QT type 2 (gene, KCNH2) after startle or during the night in adult females-particularly early post-partum, and long QT type 3 and Brugada syndrome (gene, SCN5A) during the night in young adult males. They are commonly misdiagnosed as seizure disorders. Fever-triggered cardiac events should also raise the suspicion of BrS. This review summarises genetics, cellular mechanisms, risk stratification and treatments. Beta blockers are the mainstay of treatment for long QT syndrome and CPVT, and flecainide is remarkably effective in CPVT. Brugada syndrome is genetically a more complex disease than the others, and risk stratification and management is more difficult.
98 citations
TL;DR: Heart failure telerehabilitation appears to be less costly and as effective for the health care provider as traditional centre-based rehabilitation.
Abstract: Background: Whilst home-based telerehabilitation has been shown non-inferior to traditional centre-based rehabilitation in patients with chronic heart failure, its economic sustainability remains unknown. This study aimed to investigate the cost-utility of a home-based telerehabilitation program. Methods: A comparative, trial-based, incremental cost-utility analysis was conducted from a health care provider's perspective. We collected data as part of a multi-centre, two-arm, non-inferiority, randomised controlled trial with 6 months follow-up. There were 53 participants randomised to either a telerehabilitation program (consisting of 12 weeks of group-based exercise and education delivered into the home via online videoconferencing) or a traditional centre-based program. Health care costs (including personnel, equipment and hospital readmissions due to heart failure) were extracted from health system records, and calculated in Australian dollars using 2013 as the base year. Health utilities were measured using the EuroQol five-dimensional (EQ-5D) questionnaire. Estimates were presented as means and 95% confidence intervals (CIs) based on bootstrapping. Costs and utility differences were plotted on a cost-effectiveness plane. Results: Total health care costs per participant were significantly lower in the telerehabilitation group (-$1,590, 95% CI: −2,822, −359) during the 6 months. No significant differences in quality-adjusted life years (0, 95% CI: −0.06, 0.05) were seen between the two groups. Conclusions: Heart failure telerehabilitation appears to be less costly and as effective for the health care provider as traditional centre-based rehabilitation.
48 citations
TL;DR: Findings argue in favour of including genetic testing in standard-of-care management of familial DCM, and prophylactic ICD implantation and early referral for heart transplantation may be indicated in genotype-positive individuals.
Abstract: Cardiac arrhythmias are frequently seen in patients with dilated cardiomyopathy (DCM) and can precipitate heart failure and death. In patients with non-ischaemic DCM, evidence for the benefit of an implantable cardioverter-defibrillator (ICD) for primary prevention of sudden cardiac death has recently been questioned. Algorithms devised to identify high-risk individuals who might benefit most from ICD implantation have focussed on clinical criteria with little attention paid to the underlying aetiology of DCM. Malignant ventricular arrhythmias often occur as a nonspecific consequence of DCM but can also be a primary manifestation of disease in heritable forms of DCM and may precede DCM onset. We undertook a literature search and identified 11 genes that have been associated with DCM and ventricular arrhythmias in multiple kindreds. Many of these genes fall into a diagnostic grey zone between left-dominant arrhythmogenic right ventricular cardiomyopathy and arrhythmic DCM. Genes associated predominantly with arrhythmic DCM included LMNA and SCN5A, as well as the more recently-reported DCM disease genes, RBM20, FLNC, and TTN. Recognition of arrhythmic DCM genotypes is important, as this may impact on clinical management. In particular, prophylactic ICD implantation and early referral for heart transplantation may be indicated in genotype-positive individuals. Collectively, these findings argue in favour of including genetic testing in standard-of-care management of familial DCM. Further studies in genotyped patient cohorts are required to establish the long-term health and economic benefits of this strategy.
46 citations
TL;DR: Among novel biomarkers, high sensitivity C-reactive protein (hsCRP) has emerged as the most promising in chronic situations, however, it seems that a combination of serum biomarkers offers more to risk stratification than either biomarker alone.
Abstract: Atherosclerosis is a major contributor to morbidity and mortality worldwide. With therapeutic consequences in mind, several risk scores are being used to differentiate individuals with low, intermediate or high cardiovascular (CV) event risk. The most appropriate management of intermediate risk individuals is still not known, therefore, novel biomarkers are being sought to help re-stratify them as low or high risk. This narrative review is presented in two parts. Here, in Part 1, we summarise current knowledge on serum (serological) biomarkers of atherosclerosis. Among novel biomarkers, high sensitivity C-reactive protein (hsCRP) has emerged as the most promising in chronic situations, others need further clinical studies. However, it seems that a combination of serum biomarkers offers more to risk stratification than either biomarker alone. In Part 2, we address genetic and imaging markers of atherosclerosis, as well as other developments relevant to risk prediction.
46 citations
TL;DR: It is demonstrated that cardiac fibrosis induced by Anth-bC can be reduced by NK-1R blockade, and the residual fibrotic response is likely due to direct Dox effects on cardiac fibroblasts to produce collagen.
Abstract: Background Cancer patients receiving anthracycline-based chemotherapy (Anth-bC) may experience early cardiac fibrosis, which could be an important contributing mechanism to the development of impaired left ventricular (LV) function. Substance P, a neuropeptide that predominantly acts via the neurokinin 1 receptor (NK-1R), contributes to adverse myocardial remodelling and fibrosis in other cardiomyopathies. We sought to determine if NK-1R blockade is effective against doxorubicin (Dox – a frequently used Anth-bC)-induced cardiac fibrosis and cardiomyocyte apoptosis. In addition, we explored the direct effects of Dox on cardiac fibroblasts. Methods Male Sprague-Dawley rats were randomised to receive saline, six cycles of Dox (1.5 mg Dox/kg/cycle) or Dox with an NK-1R antagonist (L732138, 5 mg/kg/daily through Dox treatment). At 8 weeks after the initial dose of Dox, LV function and histopathological myocardial fibrosis and cell apoptosis were assessed. Collagen secretion was measured in vitro to test direct Dox activation of cardiac fibroblasts. Results Rats undergoing Dox treatment (9 mg/kg cumulative dose) developed cardiac fibrosis and cardiomyocyte apoptosis. NK-1R blockade partially mitigated cardiac fibrosis while completely preventing cardiomyocyte apoptosis. This resulted in improved diastolic function. Furthermore, we found that Dox had direct effects on cardiac fibroblasts to cause increased collagen production and enhanced cell survival. Conclusions This study demonstrates that cardiac fibrosis induced by Anth-bC can be reduced by NK-1R blockade. The residual fibrotic response is likely due to direct Dox effects on cardiac fibroblasts to produce collagen.
44 citations
TL;DR: The pathogenesis, diagnosis and treatment of ACM in the contemporary era is outlined, especially in differentiating ACM from other conditions such as benign right ventricular arrhythmias, channelopathies such as Brugada, or the Athlete's Heart.
Abstract: Arrhythmogenic cardiomyopathy (ACM) is now commonly used to describe any form of non-hypertrophic, progressive cardiomyopathy characterised by fibrofatty infiltration of the ventricular myocardium. Right ventricular (RV) involvement refers to the classical arrhythmogenic right ventricular cardiomyopathy, but left ventricular, or bi-ventricular involvement are now recognised. ACM is mostly hereditary and associated with mutations in genes encoding proteins of the intercalated disc. ACM classically manifests as ventricular arrhythmias, and sudden death may be the first presentation of the disease. Heart failure is seen with advanced stages of the disease. Diagnosis can be challenging due to variable expressivity and incomplete penetrance, and is guided by established Taskforce criteria that incorporate electrical features (12-lead electrocardiography (ECG), features of ventricular arrhythmias), structural features (on imaging via echo and cardiac magnetic resonance imaging [MRI]), tissue characteristics (via biopsy), and familial/genetic evaluation. Electrical abnormalities may precede structural alterations, which also make diagnosis challenging, especially in differentiating ACM from other conditions such as benign right ventricular arrhythmias, channelopathies such as Brugada, or the Athlete's Heart. Genetic testing is critical in identifying familial mutations and initiating cascade testing, but finds a pathogenic mutation in only ∼50% of patients. Some critical genotype-phenotype correlations do exist and may help guide risk stratification and give clues to disease progression. Therapeutic strategies include restriction from high endurance and competitive sports, s-blockers, antiarrhythmic drugs, heart failure medications, implantable cardioverter-defibrillators and combined endocardial/epicardial catheter ablation. Ablation has emerged as the treatment of choice for recurrent ventricular arrhythmias in ACM. This state-of-the-art review outlines the pathogenesis, diagnosis and treatment of ACM in the contemporary era.
41 citations
TL;DR: An emergent treatment approach is warranted with emergent transfer to a high-volume centre for ventricular arrhythmia management with a multi-modality approach including ICD reprogramming, sympathetic blockade, and anti-arrhythmic drugs, and adjunctive intervention techniques.
Abstract: Cardiac electrical storm (ES) is characterised by three or more discrete episodes of ventricular arrhythmia within 24hours, or incessant ventricular arrhythmia for more than 12hours. ES is a distinct medical emergency that portends a significant increase in mortality risk and often presages progressive heart failure. ES is also associated with psychological morbidity from multiple implanted cardioverter defibrillator (ICD) shocks and exponential health resource utilisation. Up to 30% of ICD recipients may experience storm in follow-up, with the risk higher in patients with a secondary prevention ICD indication. Storm recurs in a high proportion of patients after an initial episode, and multiple storm clusters may occur in follow-up. The mechanism of storm remains elusive but is likely influenced by a complex interplay of inciting triggers (e.g., ischaemia, electrolyte disturbances), with autonomic perturbations acting on a vulnerable structural and electrophysiologic substrate. Triggers can be identified only in a minority of patients. An emergent treatment approach is warranted, if possible with emergent transfer to a high-volume centre for ventricular arrhythmia management with a multi-modality approach including ICD reprogramming, sympathetic blockade (sedation, intubation, ventilation, beta blockers), and anti-arrhythmic drugs, and adjunctive intervention techniques, such as catheter ablation and neuraxial modulation (e.g., thoracic epidural anaesthesia, stellate ganglion block). Outcomes of catheter ablation of ES are excellent with resolution of storm in over 90% of patients at 1year with a low complication rate (∼2%). ES may occur in the absence of structural heart disease in the context of channelopathies, Brugada syndrome, early repolarisation and premature ventricular contraction-induced ventricular fibrillation. There are unique treatment approaches to these conditions that must be recognised. This state-of-the-art review will summarise the incidence, mechanism, and multi-modality treatment of ES in the contemporary era.
39 citations
TL;DR: Genetic and imaging markers, and other developments in predicting risk, are addressed, with new methodologies, such as proteomics and metabolomics, discoveries of new clinically applicable biomarkers are expected.
Abstract: This is Part 2 of a two-part review summarising current knowledge on biomarkers of atherosclerosis. Part 1 addressed serological biomarkers. Here, in part 2 we address genetic and imaging markers, and other developments in predicting risk. Further improvements in risk stratification are expected with the addition of genetic risk scores. In addition to single nucleotide polymorphisms (SNPs), recent advances in epigenetics offer DNA methylation profiles, histone chemical modifications, and micro-RNAs as other promising indicators of atherosclerosis. Imaging biomarkers are better studied and already have a higher degree of clinical applicability in cardiovascular (CV) event prediction and detection of preclinical atherosclerosis. With new methodologies, such as proteomics and metabolomics, discoveries of new clinically applicable biomarkers are expected.
39 citations
TL;DR: The natural course in terms of true growth, substantial growth, and stage shift differed significantly according to their nodule type, which could contribute to the development of follow-up guidelines and management strategy of pulmonary SSNs.
Abstract: Background The long-term natural course and outcomes of subsolid nodules (SSNs) in terms of true growth, substantial growth, and stage shift need to be clarified. Methods Between 2002 and 2016, 128 subjects with persistent SSNs of 3 cm or smaller were enrolled. The baseline and interval changes in the series computed tomography (CT) findings during the follow-up period were subsequently reviewed. Results The mean follow-up period was 3.57 ± 2.93 years. The cumulative percentage of growth nodules of the part-solid nodule (PSN) group was significantly higher than that of the ground-glass nodule (GGN) group by Kaplan-Meier estimation (all p Conclusions The natural course in terms of true growth, substantial growth, and stage shift differed significantly according to their nodule type, which could contribute to the development of follow-up guidelines and management strategy of pulmonary SSNs.
36 citations
TL;DR: In CS, high PWD and abnormal P-wave axis are independent predictors of AF, representing useful tools to identify patients at high-risk of AF.
Abstract: Background Prolonged screening for the presence of atrial fibrillation (AF) is recommended after cryptogenic stroke (CS) and different electrocardiographic markers of atrial cardiopathy have been proposed as tools to identify patients at high-risk for AF. Aim The aim of this study was to evaluate the relationship between different electrocardiographic parameters and in-hospital AF occurrence after acute CS. Method In total, 222 patients with CS underwent 12-lead resting electrocardiogram (ECG) at admission and 7-day in-hospital ECG monitoring in order to evaluate the possible occurrence of silent AF. At admission, the following indices were evaluated: maximum and minimum P-wave duration (P max and P min), P-wave dispersion (PWD), P-wave index, P-wave axis, atrial size. Patients were dichotomised into two groups according to the detection of AF during 7-day in-hospital ECG monitoring and a logistic regression model was constructed to determine the predictors of AF. Results Atrial fibrillation was detected in 44 patients. Those in the AF group had a significantly higher PWD, P-wave index, PR interval, and greater frequency of abnormal P-wave axis than those in the no AF group. The following variables were found to be the main predictors for AF: age (odds ratio [OR] 1.41 for 5 years, 95% confidence interval [CI] 1.15–1.72), PWD (OR 1.92 for 10 ms, 95% CI 1.45–2.55), abnormal P-wave axis (OR 3.31, 95% CI 1.49–7.35). Conclusions In CS, high PWD and abnormal P-wave axis are independent predictors of AF, representing useful tools to identify patients at high-risk of AF.
TL;DR: The CAR may be a useful inflammation-based risk score to predict AKI development in STEMI patients treated with pPCI, and was independent predictors of AKI.
Abstract: Background The relationship between acute kidney injury (AKI) and C-reactive protein (CRP) and albumin has been previously demonstrated in patients with ST elevation myocardial infarction (STEMI) treated with primary percutaneous coronary intervention (pPCI). However, to our knowledge, CRP to albumin ratio (CAR), a newly introduced inflammation-based risk score, has not yet been studied. In this study, we aimed to investigate the possible relationship between the CAR and AKI. Method A total of 815 consecutive STEMI patients treated with pPCI were reviewed. Results One hundred ten 110 (13.5%) patients developed AKI in the study population. The subjects were divided into two groups according to AKI development. The in-hospital mortality rate was higher in patients with AKI than those without AKI (15.5% vs. 1.3%; p Conclusion The CAR may be a useful inflammation-based risk score to predict AKI development in STEMI patients treated with pPCI.
TL;DR: This paper will highlight commonly used measures of right ventricular structure and function by echocardiography along with their strengths and weaknesses.
Abstract: Assessment of right ventricular (RV) structure and function by echocardiography has largely been qualitative in the past. More recent approaches emphasise the quantification of RV structure from multiple echocardiographic views and quantification of multiple parameters of RV function. Current echocardiographic examinations should include at least two quantitative measures of RV function. This paper will highlight commonly used measures along with their strengths and weaknesses. With further technical developments in three-dimensional and myocardial deformation imaging and as more outcome data become available it is likely that further quantitative assessment will become routine and be used to guide diagnosis and treatment choices.
TL;DR: Strain analysis has come to the forefront more recently as a more sensitive measure of myocardial function than LV ejection fraction, and its utility in detection of early subclinical LV dysfunction, defining regional variation in specific cardiomyopathies, use in diagnosis and prognostic utility of strain analysis in various cardiovascular conditions are summarized.
Abstract: The accurate evaluation of left ventricular (LV) function has been central to monitoring of therapy, institution of specific therapeutic interventions and as a prognostic marker for risk stratification in a variety of cardiovascular conditions. However, LV ejection fraction, the most commonly used measure of LV systolic function, is a ‘coarse’ measure of global LV function, with several limitations. Strain analysis, a measure of myocardial deformation, has come to the forefront more recently as a more sensitive measure of myocardial function than LV ejection fraction. Its utility in detection of early subclinical LV dysfunction, defining regional variation in specific cardiomyopathies, utility to monitor improvement with therapy and as a prognostic marker in a variety of cardiac conditions has led to its increasing use in clinical practice. This review will briefly summarise specific methodological aspects, use in diagnosis and prognostic utility of strain analysis in various cardiovascular conditions.
TL;DR: An overview of recent findings in the field of glucose variability and its possible relationship with coronary artery disease concludes that glucose variability may be a marker of increased progression of coronary disease and plaque vulnerability.
Abstract: Fasting blood glucose, postprandial blood glucose and glycated haemoglobin are considered three important indicators for diabetes treatment. There is increasing evidence that glucose variability has more detrimental effects on the coronary arteries than does chronic sustained hyperglycaemia. This overview summarises recent findings in the field of glucose variability and its possible relationship with coronary artery disease. Glucose variability may be a marker of increased progression of coronary disease and plaque vulnerability. It might be a potential new therapeutic target for secondary prevention of coronary artery disease. Future studies will focus on the early detection and control of glucose variability to improve the clinical outcomes in patients with coronary artery disease.
TL;DR: Left ventricular assist devices can reverse pulmonary hypertension WHO Group 2 with significantly elevated PVR; this effect is not dependent on the baseline PVR, and is maintained up to one year post cardiac transplantation.
Abstract: Background Pulmonary hypertension secondary to left heart disease (WHO Group 2) is a known risk factor in patients with heart failure. The favourable effect of left ventricular assist devices (LVAD) on pulmonary hypertension has been demonstrated before, although this effect has not been well-studied in advanced pulmonary arterial bed disease with a significant elevation in pulmonary vascular resistance. Methods We reviewed the records of 258 LVAD patients in our institution. Patients with elevated mean pulmonary artery pressure (mPAP > 25 mmHg) and elevated pulmonary vascular resistance (PVR ≥3 Wood units) were included in the study. Patients were divided into two groups based on their baseline PVR (PVR = 3–5 Wood units (WU) vs. PVR > 5 WU). The groups were studied for the changes in their pulmonary haemodynamics after the placement of LVAD. Results Fifty-one (51) patients were included in the study. All patients showed a significant improvement in their pulmonary haemodynamic parameters post LVAD placement. In the group with the higher PVR, mPAP dropped from a baseline of 43 ± 7 mmHg to 22 ± 6 mmHg post LVAD placement (p Conclusions Left ventricular assist devices can reverse pulmonary hypertension WHO Group 2 with significantly elevated PVR; this effect is not dependent on the baseline PVR, and is maintained up to one year post cardiac transplantation.
TL;DR: Traditional methods as well as newer echocardiographic methods in the setting of pulmonary hypertension are discussed, which have enabled three-dimensional assessment of the right ventricle to assess right ventricular volume and contractility.
Abstract: Pulmonary hypertension is a progressive and often fatal disease that frequently presents with dyspnoea on exertion and results in increased right ventricular afterload and right ventricular failure. Although cardiac catheterisation is required for a formal diagnosis, transthoracic echocardiography (TTE) has a central role as a screening tool in those with symptoms and those at risk for developing pulmonary vascular disease. Echocardiographic techniques can be employed to estimate pulmonary artery pressure and resistance, right atrial pressure as well as to derive indirect information about right heart structure and function. Potential causes for pulmonary hypertension may also be identified such as congenital heart disease or left ventricular diastolic dysfunction. An increasing body of evidence has demonstrated the important prognostic utility of echocardiographic data in pulmonary hypertension and highlighted the potential for TTE to help clinicians understand whether treatment responses have been adequate or an escalation in therapy is necessary, as therapeutic options continue to expand for patients with pulmonary arterial hypertension. Although traditional echocardiographic techniques only allow surrogate measures of right ventricular systolic function due to the complex shape of the chamber, newer techniques have enabled three-dimensional assessment of the right ventricle to assess right ventricular volume and contractility. This review will discuss traditional methods as well as newer echocardiographic methods in the setting of pulmonary hypertension.
TL;DR: PAPi was independently associated with survival in PAH, highlighting the utility of PAPi in combination with other key measures for risk stratification in this population.
Abstract: Background Pulmonary artery (PA) pulsitility index (PAPi) is a novel haemodynamic index shown to predict right ventricular failure in acute inferior myocardial infarction and post left ventricular assist device surgery. We hypothesised that PAPi calculated as [PA systolic pressure – PA diastolic pressure]/right atrial pressure (RAP) would be associated with mortality in the National Institutes of Health Registry for Primary Pulmonary Hypertension (NIH-RPPH). Methods The impact of PAPi, the Pulmonary Hypertension Connection (PHC) risk score, right ventricular stroke work, pulmonary artery capacitance (PAC), other haemodynamic indices, and demographic characteristics was evaluated in 272 NIH-RPPH patients using multivariable Cox proportional hazards (CPH) regression and receiver operating characteristic (ROC) analysis. Results In the 272 patients (median age 37.7 +/− 15.9 years, 63% female), the median PAPi was 5.8 (IQR 3.7–9.2). During 5 years of follow-up, 51.8% of the patients died. Survival was markedly lower (32.8% during the first 3 years) in PAPi quartile 1 compared with the remaining patients (58.5% over 3 years in quartiles 2–4; p Conclusions Pulmonary artery pulsatility index was independently associated with survival in PAH, highlighting the utility of PAPi in combination with other key measures for risk stratification in this population.
TL;DR: Emphasis on increasing awareness of the principles of palliative care in the health care community, as well as addressing organisational issues will improve the care delivered to patients with chronic heart failure.
Abstract: Background Chronic heart failure is a complex and multifaceted syndrome characterised by an unpredictable trajectory, high symptom burden and reduced quality of life. Although palliative care is recommended, patient, provider and system factors limit access. Aim To examine the knowledge, attitudes and perspectives of health care professionals towards end of life care and palliative care for patients with chronic heart failure. Design This is an integrative review. Data sources CINAHL, Academic Search Complete and SCOPUS were searched. Specific inclusion criteria and search terms were used. The integrative review method entailed analysing data from primary articles using the constant comparison method and then synthesising data. Results Twenty-six (26) articles were selected that explored health care professionals’ perspectives towards end of life care and palliative care. The categories that emerged were grouped into patient, provider and system issues. Most health care professionals involved in providing care to heart failure patients have misperceptions of palliative care, often confusing it with end of life and hospice care. This hinders patients’ access to palliative care as determining the end of life period in heart failure is difficult. Conclusions Exploring health care professionals’ perspectives towards the delivery of end of life care and palliative care is important for understanding how their practice influences the delivery of palliative care for heart failure patients. Emphasis on increasing awareness of the principles of palliative care in the health care community, as well as addressing organisational issues will improve the care delivered to these patients.
TL;DR: This state-of-the-art review will summarise the incidence, mechanism, multimodal assessment and catheter ablation-based management of VA in NICM.
Abstract: Non-ischaemic cardiomyopathy (NICM) encompasses a heterogeneous group of disorders that includes genetic, idiopathic, post viral and inflammatory cardiomyopathies. NICM is associated with an increased risk of ventricular arrhythmias (VAs), namely in the form of ventricular tachycardia (VT). Although implanted cardiac defibrillators (ICD) may prevent sudden death from VA, NICM patients may suffer from recurrent symptoms and ICD therapies, and anti-arrhythmic drug side effects. Catheter ablation is highly efficacious in NICM, however poses unique challenges when compared to post myocardial infarction substrates. NICM substrates are fundamentally different in scar location, extent, and transmurality which results in variable electrophysiologic properties and less apparent ablation targets during sinus rhythm, compared to ischaemic cardiomyopathy. NICM substrates can be intramural and/or epicardial, posing challenges to accessibility, which likely accounts for the observed higher rates of arrhythmia recurrence following ablation. Substrate location is influenced by the underlying aetiology (inflammatory, genetic), and can be gleaned from a combination of unique 12-lead electrocardiogram VT patterns, distribution of late gadolinium enhancement on cardiac magnetic resonance imaging, and electroanatomic voltage mapping. With the high proportion of intramural substrate in NICM, novel techniques have become increasingly common in recent years, including sequential, simultaneous or bipolar ablation on opposite myocardial surfaces to achieve greater lesion depth; use of half normal saline for irrigation; use of a novel retractable needle within an endocardial catheter; and transcoronary/venous ethanol ablation to target more inaccessible regions. Epicardial approaches have also been improved in recent years, with advents such as the needle-in-needle technique to reduce the risk of pericardial bleeding and phrenic nerve displacement, and hybrid surgical approaches to facilitate epicardial access in the presence of adhesions. Non-invasive cardiac radiation holds promise for the future. This state-of-the-art review will summarise the incidence, mechanism, multimodal assessment and catheter ablation-based management of VA in NICM.
TL;DR: Early administration of nicorandil distal to the vascular lesion during PCI in STEMI patients may reduce the incidence of reperfusion injury, and improve short-term clinical outcomes.
Abstract: Background To determine whether nicorandil administration distal to the thrombus in the coronary artery during percutaneous coronary intervention (PCI) in acute ST-segment elevation myocardial infarction (STEMI) patients reduced the incidence of no-reflow phenomenon, reperfusion injury, and adverse events. Methods This randomised controlled trial involved 170 STEMI patients who underwent PCI. All patients underwent thrombectomy and tirofiban injection (10 μg/kg) distal to the vascular lesion via a suction catheter, followed by nicorandil (84 patients; 2 mg) or saline injection (86 patients; 2 mL) at the same site. The primary endpoint (major adverse cardiac events, MACEs) was 6-month cardiovascular mortality or unplanned readmission rate due to worsening congestive heart failure. The secondary endpoints were thrombolysis in myocardial infarction (TIMI) grade, TIMI myocardial perfusion grade (TMPG), resolution of ST-segment elevation (defined as >50% decrease in ST elevation); and ventricular arrhythmias. Results Upon Kaplan-Meier analysis, freedom from MACEs was 92.9% in the nicorandil group and 81.4% in the placebo (p = 0.026). The numbers of patients achieving TIMI grade 3 (95.24% vs. 86.05%; p = 0.040) and TMPG 3 (94.05% vs. 83.72%; p = 0.033) were greater in the nicorandil group than in the control group. Resolution of ST-segment elevation occurred in 84.52% and 68.60% patients in the nicorandil and control groups, respectively (p = 0.014). Ventricular arrhythmias occurred in 5.95% and 16.28% patients in the nicorandil and control groups, respectively (p = 0.032). Conclusions Early administration of nicorandil distal to the vascular lesion during PCI in STEMI patients may reduce the incidence of reperfusion injury, and improve short-term clinical outcomes. Trial registration number: NCT02435797.
TL;DR: The challenge for the future is finding a risk stratification test, or combination of tests, that adequately select patients at high risk of SCD with low competing risk of non-sudden death.
Abstract: Sudden Cardiac Death (SCD) is a major public health issue, accounting for half of all cardiovascular deaths world-wide. The implantable cardioverter-defibrillator (ICD) has been solidified as the cornerstone therapy in primary prevention of SCD in ischaemic and non-ischaemic cardiomyopathy. However, what has become increasingly clear is that the left ventricular ejection fraction (LVEF) is an inadequate tool to select patients for a prophylactic ICD, despite its widespread use for this purpose. Use of LVEF alone has poor specificity for arrhythmic versus non-arrhythmic death. In addition, the vast majority of sudden deaths occur in patients with more preserved cardiac function. Alternate predictors of sudden death include electrophysiology study, non-invasive markers of electrical instability, myocardial fibrosis, genetic and bio-markers. The challenge for the future is finding a risk stratification test, or combination of tests, that adequately select patients at high risk of SCD with low competing risk of non-sudden death.
TL;DR: Elevated homocysteine was modestly associated with an increased risk of incident AF, but the C677T MTHFR mutation was not associated with AF risk, suggesting that homocy steine may be a novel risk marker for AF rather than a causal risk factor.
Abstract: Background Although many studies have investigated the association of blood homocysteine with major cardiovascular diseases such as coronary heart disease and stroke, research on its association with atrial fibrillation (AF) is scarce. Methods We analysed data from Atherosclerosis Risk in Communities (ARIC) Study (n = 492, age 45–64 years) and Multi-Ethnic Study of Atherosclerosis (MESA) (n = 6,641, age 45–84 years). Results During the 10,106 and 67,613 person-years of follow-up, we identified 85 and 351 AF events in ARIC and MESA, respectively. An age-, sex-, and race-adjusted model showed dose-response relations between plasma homocysteine concentrations and AF incidence in both ARIC and MESA. Further adjustments for other AF risk factors did not change the associations. In the fully adjusted model, a meta-analysis of both studies showed a significant association between homocysteine and AF [hazard ratio (95% confidence interval) per 1 unit increment in log2(homocysteine), 1.27 (1.01–1.61)]. Individuals with higher levels of all three B vitamins (vitamin B6 and B12, and folate) had a lower risk of AF, but those associations were not statistically significant. In the full ARIC cohort [n = 12,686 (2079 AF events)], there was no association between the C677T methylenetetrahydrofolate reductase (MTHFR) mutation and AF. Conclusions In the prospective population-based ARIC and MESA cohorts, elevated homocysteine was modestly associated with an increased risk of incident AF, but the C677T MTHFR mutation was not associated with AF risk, suggesting that homocysteine may be a novel risk marker for AF rather than a causal risk factor.
TL;DR: The Tai Chi program is a safe, effective and feasible method to improve exercise capacity and health-related quality of life in people with COPD.
Abstract: Background Although several studies have assessed the effect of Tai Chi in management of chronic obstructive pulmonary disease (COPD), these studies have a wide sample variation and convey inconclusive results. This study aims to determine if a 3-month Tai Chi program improves lung function, exercise capacity, and health related quality of life (HRQoL) in people with COPD. Methods A randomised controlled, single blind trial was undertaken. Patients were randomly allocated to either Tai Chi group (n = 26) or control group (n = 24). Participants in the Tai Chi group received a Tai Chi exercise program three times weekly for 3-months while participants in the control group were advised to maintain their routine activities. Outcome measures included lung function, 6-minute walk distance (6WMD) and COPD Assessment Test (CAT). The measurements took place at baseline and immediately after the 3-month intervention period. Results Of 50 participants, 46 completed the intervention. Compared to control, Tai Chi significantly increased 6WMD (mean difference 60.5m, 95% CI 30.27–78.69), and reduced score of CAT (mean difference 14 points, 95% CI 11–24). An 86% compliance to the Tai Chi training was noted and no adverse events were observed in Tai Chi group. Conclusions The Tai Chi program is a safe, effective and feasible method to improve exercise capacity and health-related quality of life in people with COPD.
TL;DR: Patients presenting with NSTEMI between 2010 and 2018 were classified as independent, single point stick (SPS), 4-wheel frame (4WF) or wheelchair dependent, and Guideline-directed medical therapy (GDMT) included aspirin, beta-blockers and statins.
Abstract: mobility status on long-term outcomes in elderly patients with NSTEMI is unknown. Methods: A retrospective analysis included 956 consecutive patients aged >85 years presenting with NSTEMI between 2010–2018. Mobility status was classified as independent, single point stick (SPS), 4-wheel frame (4WF) or wheelchair dependent. Guideline-directed medical therapy (GDMT) included aspirin, beta-blockers and statins. The primary outcome was all-cause mortality.
TL;DR: Frequent ventricular ectopy is a common clinical presentation in patients suffering idiopathic ventricular outflow tract arrhythmias, and although usually associated with a good prognosis, some patients may develop an ectopy-mediated cardiomyopathy or, rarely, ectopy topline arrhythmia; catheter ablation is the treatment of choice in those patients.
Abstract: Frequent ventricular ectopy is a common clinical presentation in patients suffering idiopathic ventricular outflow tract arrhythmias. These are focal arrhythmias that generally occur in patients without structural heart disease and share a predilection for characteristic anatomic sites of origin. Mechanistically, they are generally due to cyclic adenosine monophosphate (cAMP)-mediated triggered activity. As a result, there is typically an exercise or catecholamine related mode of induction and often a sensitivity to suppression with adenosine. Treatment options include clinical surveillance, medical therapy with anti-arrhythmic agents or catheter ablation. Medical therapy may offer symptomatic benefit but may have side-effects and usually results in burden reduction rather than eradication of ectopy. Catheter ablation using contemporary mapping techniques, whilst associated with some inherent procedural risk, is a potentially curative and safe option in most patients. Although usually associated with a good prognosis, some patients may develop an ectopy-mediated cardiomyopathy or, rarely, ectopy-induced polymorphic ventricular arrhythmias; catheter ablation is the treatment of choice in those patients.
TL;DR: Over time, there has been increased access to non-primary PCI; shorter door-to-balloon times for PPCI; less adverse events in-hospital and fewer readmissions for unplanned revascularisation without the realisation of reduced mortality in- hospital or at 6 months.
Abstract: Background Increased access to reperfusion for ST elevation myocardial infarction (STEMI) has contributed to reduced mortality internationally. We describe temporal trends in pre-hospital care, in-hospital management and outcomes of the STEMI population in Australia. Methods Temporal trends with multiple regression analysis on the management and outcomes of STEMI patients enrolled across 46 Australian hospitals in the Australian cohort of the Global Registry of Acute Coronary Events (GRACE) and the Cooperative National Registry of Acute Coronary Care Guideline Adherence and Clinical Events (CONCORDANCE) between February 1999 and August 2016. Results 4,110 patients were treated for STEMI, mean age 62.5 ± 13.7years (SD). The median door-to-balloon time of primary percutaneous coronary intervention (PPCI) decreased by 11 minutes (p Conclusions Over time, there has been increased access to non-primary PCI; shorter door-to-balloon times for PPCI; less adverse events in-hospital and fewer readmissions for unplanned revascularisation without the realisation of reduced mortality in-hospital or at 6 months. Trial registration CONCORDANCE Registry ACTRN: 12614000887673.
TL;DR: A small magnitude of multi-planar motion at the sternal edges, at the mid-sternum, was demonstrated during dynamic upper limb and trunk tasks in a cohort of cardiac surgery patients post-stERNotomy, over the first 3 postoperative months.
Abstract: Background Despite a paucity of evidence, patients following cardiac surgery via median sternotomy are routinely prescribed sternal precautions that restrict upper limb and trunk movements, with the rationale of reducing postoperative sternal complications such as sternal wound dehiscence, instability, infection and/or pain. The primary aim of this study was to measure motion at the sternal edges during dynamic upper limb and trunk tasks to better inform future sternal precautions and optimise postoperative recovery. Motion at the sternal edges was measured using ultrasound, which has been demonstrated to be a clinically valid and reliable measure in patients following cardiac surgery. Methods Seventy-five (75) patients following cardiac surgery via median sternotomy with conventional stainless steel wire closure were recruited. Motion at the sternal edges in the lateral (coronal plane) and anterior-posterior (sagittal plane) directions was measured at the level of the fourth intercostal space (mid-sternum) using ultrasound. Ultrasound measures were taken at rest and during five dynamic upper limb and trunk tasks (deep inspiration, cough, unilateral and bilateral upper limb elevation and sit to stand), over the first 3 postoperative months (3 to 7 days, 6 weeks and 3 months postoperatively). Sternal pain, functional status and sternal healing were also observed over the same postoperative period. Results The magnitude of overlap of the sternal edges in the lateral direction, and separation of the sternal edges in the anterior-posterior direction, both significantly decreased by 0.01 cm, over the first 3 postoperative months (p Conclusions A small magnitude of multi-planar motion at the sternal edges, at the mid-sternum, was demonstrated during dynamic upper limb and trunk tasks in a cohort of cardiac surgery patients post-sternotomy, over the first 3 postoperative months. Future research investigating motion at different levels of the sternum, with varying methods of sternal closure, and over a longer postoperative period is warranted to better inform sternal precautions and optimise postoperative recovery.
TL;DR: Mechanical circulatory support devices may facilitate haemodynamic stability and preserve end organ perfusion during sustained VT to permit mapping for long periods, and MCS has potential key advantages including maintenance of vital organ perfusions.
Abstract: Mapping of scar-related ventricular tachycardia (VT) in structural heart disease is fundamentally driven by identifying the critical isthmus of conduction that supports re-entry in and around myocardial scar. Mapping can be performed using activation and entrainment techniques during VT, or by substrate mapping performed in stable sinus or paced rhythm. Activation and entrainment mapping requires the patient to be in continuous VT, which may not be haemodynamically tolerated, or, if tolerated, may lead to adverse sequelae related to impaired end organ perfusion. Mechanical circulatory support (MCS) devices may facilitate haemodynamic stability and preserve end organ perfusion during sustained VT to permit mapping for long periods. Available options for haemodynamic support include an intra-aortic balloon pump (IABP), TandemHeart left atrial to femoral artery bypass system (CardiacAssist Inc., Pittsburgh, PA, USA), Impella left ventricle (LV) to aorta flow-assist system (Abiomed, Danvers, MA, USA), and extracorporeal membrane oxygenation (ECMO); the bypass and assist devices provide far better augmentation of cardiac output than IABP. MCS has potential key advantages including maintenance of vital organ perfusion, reduction of intra-cardiac filling pressures, reduction of LV volumes, wall stress, and myocardial consumption of oxygen, and improvement of coronary perfusion during prolonged periods of VT induction and/or mapping. Observational studies show MCS allows for longer duration of mapping, and increased likelihood of VT termination, without an increased risk of peri-procedural mortality or VT recurrence in follow-up, despite being used in a significantly sicker cohort of patients. However, MCS has increased risk of complications related to vascular access, bleeding, thromboembolic risk, mapping system interference, increase procedural complexity and increased cost. Acute haemodynamic decompensation occurs in ∼11% of patients undergoing VT ablation, and is associated with increased mortality. Prospectively identifying patients at risk of acute haemodynamic decompensation in the peri-procedural period may allow prophylactic MCS. Although observational studies of MCS in patients at high risk of haemodynamic decompensation are encouraging, its benefit needs to be proven in randomised trials. This review will summarise the indication for MCS, forms of MCS, procedural outcomes, complications and utility of MCS during VT ablation.