Mark Dennis

Extracorporeal cardiopulmonary resuscitation for refractory cardiac arrest: A multicentre experience.

AIM To describe the ECPR experience of two Australian ECMO centres, with regards to survival and neurological outcome, their predictors and complications. METHODS Retrospective observational study of prospectively collected data on all patients who underwent extracorporeal cardiopulmonary resuscitation (ECPR) at two academic ECMO referral centres in Sydney, Australia. MEASUREMENTS AND MAIN RESULTS Thirty-seven patients underwent ECPR, 25 (68%) were for in-hospital cardiac arrests. Median age was 54 (IQR 47-58), 27 (73%) were male. Initial rhythm was ventricular fibrillation or pulseless ventricular tachycardia in 20 patients (54%), pulseless electrical activity (n=14, 38%), and asystole (n=3, 8%). 27 (73%) arrests were witnessed and 30 (81%) patients received bystander CPR. Median time from arrest to initiation of ECMO flow was 45min (IQR 30-70), and the median time on ECMO was 3days (IQR 1-6). Angiography was performed in 54% of patients, and 27% required subsequent coronary intervention (stenting or balloon angioplasty 24%). A total of 13 patients (35%) survived to hospital discharge (IHCA 33% vs. OHCA 37%). All survivors were discharged with favourable neurological outcome (Cerebral Performance Category 1 or 2). Pre-ECMO lactate level was predictive of mortality OR 1.35 (1.06-1.73, p=0.016). CONCLUSIONS In selected patients with refractory cardiac arrest, ECPR may provide temporary support as a bridge to intervention or recovery. We report favourable survival and neurological outcomes in one third of patients and pre-ECMO lactate levels predictive of mortality. Further studies are required to determine optimum selection criteria for ECPR.

Assessment of cardiovascular risk in diabetes: Risk scores and provocative testing

Cardiovascular disease (CVD) is the leading cause of morbidity and mortality among patients with diabetes mellitus, who have a risk of cardiovascular mortality two to four times that of people without diabetes. An individualised approach to cardiovascular risk estimation and management is needed. Over the past decades, many risk scores have been developed to predict CVD. However, few have been externally validated in a diabetic population and limited studies have examined the impact of applying a prediction model in clinical practice. Currently, guidelines are focused on testing for CVD in symptomatic patients. Atypical symptoms or silent ischemia are more common in the diabetic population, and with additional markers of vascular disease such as erectile dysfunction and autonomic neuropathy, these guidelines can be difficult to interpret. We propose an algorithm incorporating cardiovascular risk scores in combination with typical and atypical signs and symptoms to alert clinicians to consider further investigation with provocative testing. The modalities for investigation of CVD are discussed.

Predictors of favourable outcome after in-hospital cardiac arrest treated with extracorporeal cardiopulmonary resuscitation: A systematic review and meta-analysis

AIMS To identify the predictors of survival to discharge in adults resuscitated with extracorporeal cardiopulmonary resuscitation (ECPR) following in-hospital cardiac arrest (IHCA). METHODS MEDLINE and ISI Web of Science were searched for eligible studies. Pooled Odds Ratio (OR) and Pooled Mean Difference (PMD) for each predictor were calculated. The quality of evidence (QOE) was evaluated according to the GRADE guidelines. RESULTS Eleven studies were included totalling 856 patients. Of these, 324 (37.9%) survived to discharge. Good neurological outcome (Cerebral Performance Category 1 or 2) occurred in 222/263 (84.4%) survivors. Survival was associated with significantly higher odds of an initial shockable rhythm (OR 1.65; 95% confidence interval [95%CI] 1.05-2.61; p=0.03), shorter low-flow time (PMD -17.15 [-20.90, -13.40]min; p<0.00001), lower lactate levels both immediately before ECPR start (PMD -4.12 [-6.0,-2.24]mmol/L; p<0.0001) and on ICU admission (PMD -4.13 [-6.38, -1.88]mmol/L; p<0.0003), lower SOFA score (PMD -1.71 [-2.93, -0.50]; p=0.006) and lower creatinine levels within 24h after ICU admission (PMD -0.37 [-0.54, -0.19]mg/dl; p<0.00001). No significant association was found between survival and age, gender, or cardiac vs. non-cardiac aetiology. The overall QOE was low or very low. CONCLUSIONS In adult IHCA treated with ECPR a shockable initial rhythm, a lower low-flow time, lower blood lactate levels before ECPR start or on ICU admission, and a lower SOFA score or creatinine levels in the first 24h after ICU admission were associated with a higher likelihood of survival. These factors could help identifying patients who are eligible for ECPR.

Adults with repaired tetralogy: low mortality but high morbidity up to middle age

Objective Survival of patients with repaired tetralogy of Fallot (rToF) into young adulthood is very good. Concerns exist, however, over long-term morbidity and mortality as these subjects reach middle age. We aimed to assess survival and the prevalence of complications in patients with rToF seen in our Adult Congenital Heart Disease (ACHD) service. Methods One hundred and sixty-eight consecutive patients with ‘simple rToF’, aged over 16 years, followed up at our tertiary-level ACHD service in Sydney, Australia since 2000, were included. We documented mortality and analysed the prospectively defined composite end points of (a) ‘Serious adverse events’, including death, heart failure hospitalisation and/or documented ventricular arrhythmia and (b) ‘Adverse events’ inclusive of the above and endocarditis, atrial arrhythmia, defibrillator and/or pacemaker implantation. Results Mean age at the last follow-up was 34±12 years, and 55% were men. There were 10 (6%) deaths, and 26 patients (16%) experienced a ‘serious adverse event’. Fifty-one patients (30%) experienced an ‘adverse event’ and 29 patients had atrial arrhythmias. One hundred and one (61%) patients had at least one pulmonary valve replacement. By age 40 years, 93% were free of serious adverse events, and 83% were free of any adverse event. By age 50 years, only 56% had not had an adverse event. Older age and history of atrial arrhythmia were predictive of serious adverse events. Conclusion Survival into mid-adulthood in patients with rToF is very good; however, a substantial number of survivors have adverse events by the age of 50 years.

Detection of Serious Complications by MR Imaging in Asymptomatic Young Adults with Repaired Coarctation of the Aorta

BACKGROUND Despite early repair, patients with aortic coarctation (CoA) continue to have a reduced life expectancy due to the development of late complications. We sought to define the rate of aortic abnormalities in patients with previous CoA repair, referred for surveillance magnetic resonance (MR) imaging. METHODS We evaluated 59 asymptomatic adults consecutively for repaired CoA with MR imaging between 2008 and 2012. RESULTS Patients were aged 29 ± 8 (16-49) years; 34 males (58%) and 34 with bicuspid aortic valve (58%). Median age at the time of initial repair was two years. Surveillance MR imaging was performed 23 ± 8 years post-procedure. The three most common interventions performed were subclavian-flap repair (25%), end-to-end repair (33%) and patch aortoplasty (33%). Re-intervention with balloon angioplasty or repeat surgery had been performed in 22% of subjects. There were 28 cases of recoarctation (48%), of which seven were at least moderate in severity. Repair site and ascending aortic aneurysm occurred in eight (14%) and four (7%) subjects, respectively. Freedom from any degree of recoarctation and other aortic complications was observed in eight subjects (14%). CONCLUSION MR imaging detected a high rate of aortic abnormalities in asymptomatic adults after CoA repair, including 27% with clinically significant recoarctation and/or local aneurysm formation.

A 10-year review of sudden death during sporting activities

BACKGROUND Sudden death during sport is a rare but devastating event. Previous research has mostly focused on sudden deaths in young competitive athletes. OBJECTIVE The purpose of this study was to characterize the demographics and etiologies of sudden cardiac death during sport in Australia. METHODS All autopsies conducted at our forensic medicine facility between 2006 and 2015 inclusive were reviewed. Sporting-related deaths among those 7-65 years of age were identified. Data collected included subject height, weight, gender, circumstances of death, and pathologic findings at autopsy. RESULTS A total of 19,740 autopsies were completed in the study period: 12,395 in subjects age 18-65 years (adults) and 385 in subjects age 7-17 years (children). There were 201 sports-related adult deaths at an incidence rate of 0.76-1.49 per 100,000 participant-years. Of the deaths, 74% were witnessed. Of the adult cases, 68% (n = 136) were due to cardiac causes, with coronary artery disease the most frequent cause (n = 90 [45%]). Structural abnormalities were common in adult cardiac deaths; 51 (38%) had cardiac weight ≥500 g, and 75 (55%) had left ventricular wall thickness >15 mm. Of the 15 child deaths, 5 (33%) were arrhythmogenic or presumed arrhythmic, and 5 (33%) were inherited cardiomyopathies (2 hypertrophic cardiomyopathy, 3 arrhythmogenic right ventricular cardiomyopathy). CONCLUSION Sudden cardiac death during sport is rare. Deaths are mostly due to coronary artery disease in adults and cardiomyopathy or arrhythmia in children. Because the majority of sports deaths are witnessed, they present an opportunity to enhance outcomes by cardiopulmonary resuscitation training and increased availability of automated external defibrillators at sports venues.

Authors’ response: Extracorporeal cardiopulmonary resuscitation probably good, but adoption should not be too fast and furious!

Callaway and Sunde1 are right when they advise caution in adoption of extracorporeal cardiopulmonary resuscitation (ECPR) given the varying definitions of what ECPR constitutes. However, we believe ECPR is not coming ‘too fast and furious’ but rather like a Formula One car, dependent on focused high performance teams, bespoke with narrow specifications and at the cutting edge. Current survival for cardiac arrest by conventional cardiopulmonary resuscitation (CCPR) is indeed dismal at around 10%.2 ECPR has led to improved outcomes compared with CCPR in many regions.3–6 ECPR consideration is in some ways analogous to resuscitative thoracotomy (RT) in trauma. Despite moderate quality of evidence, RT is strongly recommended in pulseless penetrating torso trauma with signs of life in ED.7 …