Ambulatory short-term mechanical circulatory support: facilitates recovery and prepares patients for definitive therapy.

Short-term mechanical circulatory support (ST-MCS) devices have been traditionally deployed in patients with cardiogenic shock, advanced heart failure, cardiovascular collapse, and cardiorespiratory failure. Limitations of the mechanical support devices are typically related to mobility of the patient since the access is frequently through femoral vasculature. This limits the time the patient can be supported by mechanical circulatory support (MCS). We describe deployment of ST-MCS using alternate access such as the subclavian/axillary artery that facilitates ambulation of the patient. These include the deployment of intra-aortic balloon pump (IABP) through the subclavian artery, Impella pump through the axillary/subclavian artery, and extracorporeal membrane oxygenation (ECMO) using the subclavian artery and jugular vein.

ECMO as a bridge to cardiac surgery: stabilizing unstable patients for a definitive procedure.

Introduction: Extracorporeal membrane oxygenation (ECMO) in adults has been used in post-cardiotomy patients who decline hemodynamically. Cardiogenic shock in patients with potential surgically correctable cardiac conditions are at significantly higher risk for post-operative morbidity and mortality. We present experience with a pre-emptive approach of ECMO institution pre-operatively to stabilize patients with cardiogenic shock. Materials and methods: This study expands on a pilot study with a group of twenty patients who were supported with ECMO pre-operatively in different institutions over a period between 2011 and 2021. The patients presented with cardiogenic shock. Peripheral veno-arterial (VA) ECMO support was used in all the patients. Cardiac surgery was performed via median sternotomy utilizing the in situ ECMO cannulae to institute cardiopulmonary bypass (CPB). Results: Seventeen patients were weaned off ECMO support following a mean duration of support of 156 h. Fifteen patients survived to discharge. The 30-day mortality and in-hospital mortality were 25% (expected 67% by European System for Cardiac Operative Risk Evaluation (EuroSCORE) II). The causes of mortality included persistent bleeding in 2 patients due to liver dysfunction, and one with low platelet counts. The other two had multi-organ failure. Conclusions: Variable period of pre-operative ECMO support provides hemodynamic stability and may prevent or reverse the multi-organ dysfunction if instituted on time in patients presenting with cardiogenic shock. This strategy allows cardiac surgery to be performed with acceptable risk.

Predictors of atrial fibrillation post coronary artery bypass graft surgery: new scoring system.

BACKGROUND: Atrial fibrillation (AF) following coronary artery bypass graft surgery (CABG) is common and results in significant increases in hospital stay and financial encumbrance. OBJECTIVE: Determine and use the predictors of postoperative AF (POAF) following CABG to develop a new predictive screening tool. METHOD: A retrospective case-control study evaluated 388 patients (98 developed POAF and 290 remained in sinus rhythm) who undertook CABG surgery at Townsville University Hospital between 2016 and 2017. The demographic profile, risk factors for AF including hypertension, age≥75 years, transient ischaemic attack or stroke, chronic obstructive pulmonary disease (HATCH) score, electrocardiography features and perioperative factors were determined. RESULTS: Patients who developed POAF were significantly older. On univariate analysis HATCH score, aortic regurgitation, increased p-wave duration and amplitude in lead II and terminal p-wave amplitude in lead V1 were associated with POAF; as were increased cardiopulmonary bypass time (103.5±33.9 vs 90.6±26.4 min, p=0.001) and increased cross clamp time. On multivariate analysis age (p=0.038), p-wave duration ≥100 ms (p=0.005), HATCH score (p=0.049) and CBP Time ≥100 min (p=0.001) were associated with POAF. Receiver operating characteristic curve demonstrated that with a cut-off of ≥2 for HATCH score, POAF could be predicted with a sensitivity of 72.8% and a specificity of 34.7%. Adding p-wave duration in lead II >100 ms and cardiopulmonary bypass time >100 min to the HATCH score increased the sensitivity to 83.7% with a specificity of 33.1%. This was termed the HATCH-PC score. CONCLUSION: Patients with HATCH scores ≥2, and those with p-wave duration >100 ms, or cardiopulmonary bypass time >100 min were at greater risk of developing POAF following CABG.

Acute changes in handgrip strength, lung function and health-related quality of life following cardiac surgery.

BACKGROUND: Handgrip strength (HGS), lung function and health-related quality of life (HRQoL) are relevant indicators of future cardiovascular risk and mortality. The impact of cardiac surgery on these predictive variables has been under-explored. The aim of this study was to determine the acute (within hospital) changes in HGS, lung function and HRQoL, and their relationships, in adults undergoing elective cardiac surgery. Further, the study examined the relationship between these variables and the predictors for lung function and HRQoL in these patients. METHODS: The study was a prospective cohort study that involved 101 patients who completed pre-operative (1-2 days before surgery) and physiotherapy discharge (5-7 days after surgery) assessments. Handgrip strength, lung function and HRQoL were assessed using JAMAR dynamometers, Vitalograph-Alpha or EasyOne spirometer, and Short-Form 36 questionnaire, respectively. Changes in these variables and their relationships were analysed using paired t-test and Pearson correlation coefficients, respectively. Prediction of lung function and HRQoL using HGS and other co-variates was conducted using regression analysis. RESULTS: At the time of physiotherapy discharge, lung function, HGS and the physical component of HRQoL were significantly (<0.001) reduced compared to their pre-operative values. Significant (<0.001) and moderate correlations were identified between HGS and lung function at pre-operation and physiotherapy discharge. Handgrip strength was a significant predictor of lung function pre-operatively but not at physiotherapy discharge. Pre-operative lung function and HRQoL, as well as other variables, were significant predictors of lung function and HRQoL during physiotherapy discharge. CONCLUSIONS: Undergoing cardiac surgery acutely and significantly reduced lung function, HGS and physical component of HRQoL in adults with cardiac disease. Assessment of HGS at physiotherapy discharge may be a poor indicator of operative changes in lung function and HRQoL. Clinicians may consider HGS as an inadequate tool in predicting lung function and HRQoL following cardiac surgery.

Cell adhesion an important determinant of myogenesis and satellite cell activity.

Skeletal muscles represent a complex and highly organised tissue responsible for all voluntary body movements. Developed through an intricate and tightly controlled process known as myogenesis, muscles form early in development and are maintained throughout life. Due to the constant stresses that muscles are subjected to, skeletal muscles maintain a complex course of regeneration to both replace and repair damaged myofibers and to form new functional myofibers. This process, made possible by a pool of resident muscle stem cells, termed satellite cells, and controlled by an array of transcription factors, is additionally reliant on a diverse range of cell adhesion molecules and the numerous signaling cascades that they initiate. This article will review the literature surrounding adhesion molecules and their roles in skeletal muscle myogenesis and repair.

Are Interactions between Epicardial Adipose Tissue, Cardiac Fibroblasts and Cardiac Myocytes Instrumental in Atrial Fibrosis and Atrial Fibrillation?

Atrial fibrillation is very common among the elderly and/or obese. While myocardial fibrosis is associated with atrial fibrillation, the exact mechanisms within atrial myocytes and surrounding non-myocytes are not fully understood. This review considers the potential roles of myocardial fibroblasts and myofibroblasts in fibrosis and modulating myocyte electrophysiology through electrotonic interactions. Coupling with (myo)fibroblasts in vitro and in silico prolonged myocyte action potential duration and caused resting depolarization; an optogenetic study has verified in vivo that fibroblasts depolarized when coupled myocytes produced action potentials. This review also introduces another non-myocyte which may modulate both myocardial (myo)fibroblasts and myocytes: epicardial adipose tissue. Epicardial adipocytes are in intimate contact with myocytes and (myo)fibroblasts and may infiltrate the myocardium. Adipocytes secrete numerous adipokines which modulate (myo)fibroblast and myocyte physiology. These adipokines are protective in healthy hearts, preventing inflammation and fibrosis. However, adipokines secreted from adipocytes may switch to pro-inflammatory and pro-fibrotic, associated with reactive oxygen species generation. Pro-fibrotic adipokines stimulate myofibroblast differentiation, causing pronounced fibrosis in the epicardial adipose tissue and the myocardium. Adipose tissue also influences myocyte electrophysiology, via the adipokines and/or through electrotonic interactions. Deeper understanding of the interactions between myocytes and non-myocytes is important to understand and manage atrial fibrillation.

Thiamine increases resident endoglin positive cardiac progenitor cells and atrial contractile force in humans: A randomised controlled trial.

BACKGROUND: The heart has an intrinsic ability to regenerate, orchestrated by progenitor or stem cells. However, the relative complexity of non-resident cardiac progenitor cell (CPC) therapy makes modulation of resident CPCs a more attractive treatment target. Thiamine analogues improve resident CPC function in pre-clinical models. In this double blinded randomised controlled trial (identifier: ACTRN12614000755639), we examined whether thiamine would improve CPC function in humans. METHODS AND RESULTS: High dose oral thiamine (one gram twice daily) or matching placebo was administered 3-5 days prior to coronary artery bypass surgery (CABG). Right atrial appendages were collected at the time of CABG, and CPCs isolated. There was no difference in the primary outcome (proliferation ability of CPCs) between treatment groups. Older age was not associated with decreased proliferation ability. In exploratory analyses, isolated CPCs in the thiamine group showed an increase in the proportion of CD34-/CD105+ (endoglin) cells, but no difference in CD34-/CD90+ or CD34+ cells. Thiamine increased maximum force developed by isolated trabeculae, with no difference in relaxation time or beta-adrenergic responsiveness. CONCLUSION: Thiamine does not improve proliferation ability of CPC in patients undergoing CABG, but increases the proportion of CD34-/CD105+ cells. Having not met its primary endpoint, this study provides the impetus to re-examine CPC biology prior to any clinical outcome-based trial examining potential beneficial cardiovascular effects of thiamine.

Cardiology, Research and Training: An Interview With Professor Eugene Braunwald.

Professor Eugene Braunwald, often referred to as the 'Father of Modern Cardiology', has contributed significantly to medicine and cardiology. He is best known for the acclaimed textbook Braunwald's Heart Disease and for being the founding chairman of the Thrombolysis in Myocardial Infarction (TIMI) Study Group. Our primary aim is to highlight his experiences and the guidance that he has to offer to future generations of medical trainees and professionals. An interview with Prof. Braunwald provided the authors with an insight into his journey in medicine. A range of questions were posed pertaining to his struggles and accomplishments in cardiology, his perspectives on the future of cardiology and research, as well as his advice to current and future medical professionals.1 Positive role models are an inspiration to all, regardless of the stage in their career. With hard work, unwavering dedication and a strong desire to make a positive difference to patients and the field, the opportunities are endless. Whether it is clinical or bench research, advances in clinical cardiology and research usually go hand-in-hand. Although primary and secondary prevention of cardiovascular disease remain of critical importance, it is now time to focus on primordial prevention to step back and reduce the development of the risk factors for the future development of cardiovascular disease in the first place. There have been significant advances in cardiology over the past two-thirds of the century during which Prof. Braunwald trained and then led the field. However, there is still much work to be done. Mentors and medical institutions alike must work towards a common goal of 'igniting the fire' within the new generation of clinicians and investigators who will then propel this important specialty to ever greater heights.

Outcomes in Dialysis-Dependent Indigenous and Non-Indigenous Patients Undergoing Cardiac Surgery at Townsville University Hospital.

PURPOSE: Dialysis-dependent patients have a high risk of cardiovascular death but also a high risk for perioperative mortality in cardiac surgery. Our study examined surgical complications and mortality in Indigenous and non-Indigenous dialysis-dependent patients undergoing cardiac surgery at a single centre. METHODOLOGY: The retrospective study reviewed 72 consecutive dialysis-dependent patients who underwent cardiac surgery between 2008 and 2018. Data was prospectively collected, and follow-up was obtained from physicians and general practitioners. Multivariable analysis was performed to determine predictors of mortality. RESULTS: The median age of Indigenous Australian patients was 60 years, compared with 65 years for non-Indigenous patients. Indigenous Australian patients had a significantly higher rate of return to theatre (43% versus 17%). The predominant reason for return to theatre for the whole cohort was postoperative bleeding (n=16, 22%). The overall early mortality rate was 10%. There were 35 late deaths (49%) and overall survival at 5 years was 40.92±6.8% (95% CI: 28-54%). History of arrhythmia (p=0.019) was a significant risk factor for mortality, whilst patients who underwent isolated coronary artery bypass grafting (p=0.004), and those who received internal mammary artery grafts (p=0.021) had a reduced hazard ratio for mortality. The median follow-up time was 29 months (IQR 10-52 mo). CONCLUSION: Dialysis-dependent Indigenous Australian patients present younger for cardiac surgery, with a higher prevalence of co-morbid diabetes and more extensive coronary artery disease. There was no statistically significant difference in early or late mortality between Indigenous and non-Indigenous patients. However, there was a higher rate of return to theatre amongst the Indigenous Australian cohort.

Prudent planning in management of mucocele of appendix.

INTRODUCTION: Appendiceal mucocele is a rare obstructive dilatation of the appendix caused by intraluminal accumulation of mucoid material. Having no typical clinical picture, patients presenting with lower right quadrant abdominal pain are sometimes mistaken for acute appendicitis. An untreated mucocele may progress leading to high mortality. CASE REPORT: A 47-year-old female presented with dull pain in the right lower abdomen, associated with generalized weakness and nausea since 6 months. Other than mild tenderness over the right iliac fossa. Physical and laboratory examination was insignificant. Abdominal sonography was doubtful between appendicular abscess and mucocele appendix. Dual contrast CT scan of abdomen was highly suggestive of an appendicular mucocele. DISCUSSION: The patient had a vertical midline incision exploratory laparotomy done and a cystic mass measuring 7 × 4 × 4 cm3 was found arising from the body of appendix. With suspicion of malignancy because of size, right hemicolectomy with ileotransverse anastomosis was done. Histopathological examination showed features of low grade appendiceal mucinous neoplasm. CONCLUSION: Pre-operative diagnosis of appendicular mucocele is difficult, nevertheless, it is important for the selection of the appropriate surgical procedure in order to prevent intra-operative complications and early surgical intervention has excellent long-term prognosis.

An arcane case report of primary intramuscular hydatid cyst of thigh.

INTRODUCTION: Hydatid diseases are a cystic parasitic infestation caused by Echinococci which are endemic to parts of India and commonly occur in agricultural workers. Primary intramuscular hydatidosis is a rare manifestation of hydatid disease. PRESENTATION OF CASE: Our case report describes a rare case of primary intramuscular hydatidosis in an agricultural worker with no involvement of any other viscera. This was diagnosed with clinical evaluation, radiological modalities and managed surgically. DISCUSSION: Hydatid disease is endemic in parts of India. Primary intramuscular hydatidosis is uncommon because the lactic acid in the muscle and muscle contractility hinders the development of cysts making it improbable diagnosis on first presentation. Hydatid cyst demonstrates a wide variety of imaging features, which can vary according to growth stage, associated complications and affected tissue. The treatment of choice is complete surgical excision of the cyst along with thorough irrigation of the surrounding soft tissues combined with the use of systemic antiparasitic drugs after surgery. CONCLUSION: In a patient of an agricultural background of cattle rearing living in an endemic region and presenting with a swelling in the musculoskeletal system, a suspicion of hydatidosis should always be kept in the clinicians mind, so that it can be diagnosed using a multimodal approach and managed properly in a timely manner.