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Refinements to conventional treatment and the development of new therapies have led to significant improvements in cancer survival. Yet, many frontline cancer treatments continue to be hindered by their significant side effects, amongst which cardiotoxicity is particularly important. Therefore, the focus of cancer management has changed; treatment is no longer aimed solely at overcoming malignancy, but emphasises early identification and treatment of potential side effects. In this regard, the cardiotoxic potential of certain anticancer agents mandate close monitoring of cardiac function, and the method of choice for monitoring is transthoracic echocardiography. Whilst this method has its limitations, a newer echocardiographic technique called myocardial strain imaging has the potential to detect early sub-clinical changes in cardiac function due to cardiotoxicity. Strain analysis has been the subject of several recent studies to evaluate its potential in monitoring cardiotoxicity, and this article reviews the recent literature and explores the potential role of myocardial strain imaging in cancer management and avenues for future research. [ABSTRACT FROM AUTHOR]

Background: This study aimed to determine whether a structured, inpatient (or Phase 1 cardiac rehabilitation), physiotherapy-supervised walking program, with or without musculoskeletal and respiratory exercises, might improve walking capacity and other parameters for patients undergoing coronary artery bypass graft surgery (CABG). Methods: Ninety-three patients awaiting first-time CABG over a 12-month period were randomised to one of three post-operative physiotherapy regimens: ‘standard intervention’, consisting of gentle mobilisation; ‘walking exercise’, consisting of a physiotherapy-supervised, moderate intensity walking program; and ‘walking/breathing exercise’, consisting of the same moderate intensity walking program, musculoskeletal exercises and respiratory exercises. Primary outcomes; six-minute walking assessment (6MWA) distance, vital capacity and health-related quality of life, were measured pre-operatively, at discharge from hospital and at four weeks following discharge. Results: Walking and walking/breathing exercise groups had significantly higher 6MWA distance (444±84m, 431±98m, respectively) than the standard intervention group (377±90m) at discharge from hospital. There was no significant difference between intervention groups for 6MWA distance at four-week follow-up. There was no significant difference between intervention groups in terms of vital capacity and health-related quality of life. Conclusions: A physiotherapy-supervised, moderate intensity walking program in the inpatient phase following CABG improves walking capacity at discharge from hospital. The performance of respiratory and musculoskeletal exercises confers no additional benefit to the measured outcomes. [Copyright &y& Elsevier]

The mechanism of reentrant tachycardia was established nearly a century ago, but the relationships between myocardial infarction and predisposition to sudden death were not unravelled until much later. In the latter half of the twentieth century many studies sought to ascertain what variables were predictive of death following myocardial infarction. Approximately one half of all deaths during the year following myocardial infarction are sudden and due to ventricular tachycardia (VT) or ventricular fibrillation (VF). We aimed to utilise non-invasive signal-averaging, along with programmed electrical stimulation of the heart, to determine whether one could predict spontaneous ventricular tachycardia and sudden death late after myocardial infarction. The sensitivity of ventricular electrical instablility (inducible ventricular tachycardia or fibrillation) as a predictor of instantaneous death or spontaneous VT was 86%, and the specificity was 83%. When other variables (delayed ventricular activation at signal-averaging, ejection fraction at gated heart pool scan, ventricular ectopic activity at ambulatory monitoring and exercise testing) were taken into account, inducible VT at electrophysiological study was the single best predictor of spontaneous VT and sudden cardiac death after myocardial infarction. The Westmead studies of Uther et al. in the decade or so from 1980 established programmed stimulation as the best predictor of sudden death after myocardial infarction. Subsequent studies by others have demonstrated a survival advantage of defibrillator implantation in patients with low ejection fraction (and inducible ventricular tachycardia) after myocardial infarction. [Copyright &y& Elsevier]

Studies from the 1980s, refined in the intervening years, have examined the milieu for ventricular tachycardia (VT) and ventricular fibrillation (VF) occurring late after acute myocardial infarction (AMI). The arrhythmogenic substrate appears to be patchy areas of fibrous tissue interdigitating with viable bundles of myocardium which have distorted orientation and tortuous interconnections. These promote conduction delay in sinus rhythm. Factors found to promote induction of VT rather than VF are longer conduction delay in sinus rhythm, larger infarct size, a more ragged infarct edge and longer ventricular extrastimulus coupling intervals. Predictors of spontaneous VT and VF late after AMI include inducible VT at electrophysiological studies (EPS), delayed conduction in sinus rhythm detected as late potentials on signal-averaged surface electrocardiogram (ECG), and low left ventricular ejection fraction (LVEF). Treatments of propensity for VT or VF after AMI include insertion of a defibrillator (ICD), which has the best track record, antiarrhythmic medication (less reliable), and ablation or excision of arrhythmogenic substrate (for refractory VT and VF). [Copyright &y& Elsevier]

With improved diagnosis and treatments, a greater percentage of breast cancer patients are achieving long-term survival. Consequently, long-term cardiotoxicity secondary to chemotherapy has become more prevalent, warranting improved cardiac surveillance. We evaluated changes in left atrial (LA) strain in breast cancer patients immediately post anthracycline (AC) therapy to assess its utility as a marker of diastolic dysfunction. This was a prospective cohort study of 128 consecutive human epidermal growth factor receptor 2 (HER2)-negative breast cancer patients who underwent transthoracic echocardiography prior to and immediately post AC treatment. Traditional left ventricular (LV) systolic and diastolic parameters and LA volumes were evaluated; additionally, LV global longitudinal strain (LV GLS) and LA phasic strain were measured. All patients had normal LV ejection fraction (>53%) post AC, though LV GLS was significantly reduced. Peak E and é velocities were reduced post AC, with no change in LA volumes. LA reservoir strain (LAS RES 34.8% vs 31.5%, p<0.001) and conduit strain (LAS CD 17.2% vs 14.4%, p<0.001) were significantly lower post AC and correlated modestly with LV diastolic parameters. Reduction in LA strain post AC was evident even in patients with preserved LV systolic and diastolic function. More patients demonstrated alteration in diastolic function (≥15% reduction in LAS RES from baseline) (32%) compared to alteration in systolic function (≥15% reduction in LV GLS) (23%). LA strain is a promising marker of early diastolic dysfunction. We demonstrate its potential utility in surveillance of breast cancer patients treated with AC. [Display omitted] [ABSTRACT FROM AUTHOR]

Background: Existing electrocardiographic (ECG) reference values were derived in middle-aged Caucasian adults. We aimed to assess the association of age, sex, body size and ethnicity on ECG parameters in a multi-ethnic Asian population.Methods: Resting 12-lead ECG and anthropometric measurements were performed in a community-based cohort of 3777 older Asians (age 64.7±9.1 years, 1467 men, 88.8% Chinese, 7.7% Malay, 3.5% Indian, body mass index [BMI] 24.0±3.9kg/m(2)).Results: Men had longer PR interval, wider QRS, shorter QTc interval and taller SV3. In both sexes, older age was associated with longer PR interval, wider QRS, larger R aVL and more leftward QRS axis, while higher BMI was associated with longer PR interval, wider QRS, larger RaVL and more negative QRS axis. There were significant inter-ethnic differences in QRS duration among men, as well as in PR and QTc intervals among women (all adjusted p<0.05). Findings were similar in a healthy subset of 1158 adults (age 61.2±9.1 years, 365 men) without cardiovascular risk factors.Conclusions: These first community-based ECG data in multi-ethnic older Asians highlight the independent effects of age, sex, body size and ethnicity on ECG parameters. [ABSTRACT FROM AUTHOR]

Background Many patients provisionally diagnosed with acute myocardial infarction (AMI) have angiographically unobstructed coronary arteries. Despite other potential causes, patients are often diagnosed as AMI with psychosocial implications and medication burden. The aim of this audit was to review such patients at our centre. Methods All patients investigated for possible AMI with coronary angiography from 2007 until 2011 at Christchurch Hospital, New Zealand, in whom cardiac troponin was elevated (with no other cause found for that elevation) but coronary angiography showed diameter stenosis <50% were reviewed. Primary outcome was two-year cardiac death and AMI (by universal definition). Results Of the 351/6493 (5.4%) who met the inclusion criteria, 180 had normal angiograms and 171 had non-obstructive coronary disease (stenosis >0% and <50%). By two years there were two cardiac deaths (0.6%) and five AMIs (1.4%). The primary outcome rate was therefore 2.0% (2.2% for those with normal angiograms and 1.8% with non-flow limiting coronary disease, p=1.000). Conclusion Patients who have presented with AMI symptoms, elevated cardiac troponin, and unobstructed coronary arteries on angiography are at very low risk of cardiac death (0.6%), AMI (1.4%) or either (2.0%) at two-year follow-up. [ABSTRACT FROM AUTHOR]

Background: Singapore is a multiethnic Asian country comprising predominantly Chinese, Malays, and Indians. We sought to study the disparities in evidence-based therapy for people from these three ethnic groups who were admitted to hospital with ST-segment elevation myocardial infarction (STEMI). We also examined its association with socioeconomic level and social network size and the influence on psychological stress level. Methods: In a prospective study, patients admitted with STEMI were recruited for a questionnaire survey. Relevant demographic and clinical data were collected. Results: A total of 364 patients were recruited and categorised based on ethnicity: Chinese (222 patients), Malays (72 patients), and Indians (70 patients). Malays and Indians were significantly younger than Chinese at the time of presentation with STEMI. Malays had significantly more children than the Chinese and Indians. Malays were in the lowest socioeconomic class, based on education level (P ≤.02) and residential type (P ≤.003). Most (87%) patients were treated with primary percutaneous coronary intervention. There were no significant differences between Chinese, Malays, and Indians in accessibility to primary percutaneous coronary intervention, symptom-to-balloon time, door-to-balloon time, and prescription of evidence-based medications. Malays had larger social networks for information support (P ≤.05) and financial support (P ≤.04) than Chinese and Indians. There were no significant differences between the three ethnic groups in satisfaction with social support. The perceived stress level was higher among Malays and Indians than Chinese. Conclusions: Although Malays were underprivileged in the socioeconomic level, no significant difference in healthcare disparities were observed among the three ethnic groups. This may be a reflection of the advancement in Singapore's healthcare system. The lower socioeconomic level may also explain the higher perceived stress level in Malays. [ABSTRACT FROM AUTHOR]