Lindsay Savage

Clozapine and incidence of myocarditis and sudden death – Long term Australian experience

BACKGROUND Clozapine is the cornerstone of therapy for refractory schizophrenia; however, the potential for cardiotoxicity is an important limitation in its use. In the current analysis we sought to evaluate the long term cardiac outcomes of clozapine therapy. METHODS All-cause mortality, incidence of sudden death and time to myocarditis were assessed in a cohort of patients maintained on clozapine between January 2009 and December 2015. All patients had regular electrocardiograms, complete blood count, clozapine levels and echocardiography as part of a formal protocol. RESULTS A total of 503 patients with treatment-resistant schizophrenia were maintained on clozapine during the study period of which 93 patients (18%) discontinued therapy with 29 (6%) deaths. The incidence of sudden death and myocarditis were 2% (n=10) and 3% (n=14) respectively. Amongst patients with sudden death, 7 out of 10 (70%) were documented to have used illicit drugs prior to death, with a tendency to weight gain also noted. The mean time to myocarditis post clozapine commencement was 15±7days. The reduction in left ventricular ejection fraction in those with myocarditis was 11±2%. CONCLUSION Myocarditis and sudden cardiac death are uncommon but clinically important complications in a cohort of patients followed while maintained on clozapine undergoing regular cardiac assessment. Further studies are required to document the role of preventive measures for left ventricular dysfunction and sudden cardiac death in this population.

Pre-hospital thrombolysis in ST-segment elevation myocardial infarction: a regional Australian experience.

OBJECTIVE The system of care in the Hunter New England Local Health District for patients with ST-segment elevation myocardial infarction (STEMI) foresees pre-hospital thrombolysis (PHT) administered by paramedics to patients more than 60 minutes from the cardiac catheterisation laboratory (CCL), and primary percutaneous coronary intervention (PCI) at the CCL for others. We assessed the safety and effectiveness of the pre-hospital diagnosis strategy, which allocates patients to PHT or primary PCI according to travel time to the CCL. DESIGN, SETTING AND PARTICIPANTS Prospective, non-randomised, consecutive, single-centre case series of STEMI patients diagnosed on the basis of a pre-hospital electrocardiogram (ECG), from August 2008 to August 2013. All patients were treated at the tertiary referral hospital (John Hunter Hospital, Newcastle). MAIN OUTCOME MEASURES The primary efficacy endpoint was all-cause mortality at 12 months; the primary safety endpoint was bleeding. RESULTS STEMI was diagnosed in 484 patients on the basis of pre-hospital ECG; 150 were administered PHT and 334 underwent primary PCI. The median time from first medical contact (FMC) to PHT was 35 minutes (IQR, 28-43 min) and to balloon inflation 130 minutes (IQR, 100-150 min). In the PHT group, 37 patients (27%) needed rescue PCI (median time, 4 h; IQR, 3-5 h). The 12-month all-cause mortality rate was 7.0% (PHT, 6.7%; PCI, 7.2%). The incidence of major bleeding (TIMI criteria) in the PHT group was 1.3%; no patients in the primary PCI group experienced major bleeding. CONCLUSION PHT can be delivered safely by paramedical staff in regional and rural Australia with good clinical outcomes.

Pros, Cons, and Organization of Prehospital Thrombolysis

BACKGROUND Early initiation of reperfusion therapy in ST-segment elevation myocardial infarction improves outcome. Prehospital thrombolysis (PHT) is 1 strategy to deliver earlier reperfusion. OBJECTIVE The goal of this study was to discuss the pros and cons of PHT and to describe the implementation of a program of PHT in the Hunter Region of Australia. METHODS Recent literature on PHT was reviewed to present a critical assessment of the evidence to support PHT. Different models of PHT are presented including the experience of the introduction of the Hunter program. RESULTS Meta-analyses of clinical trials and registries have shown that PHT significantly decreases the time to thrombolysis, with reduction in the incidence of cardiogenic shock and a trend to a mortality benefit. The STREAM study reinforces current policy, which favors primary percutaneous coronary intervention (PCI) over thrombolysis, providing that PCI can be performed within an appropriate time interval; emphasizes that timely thrombolysis linked to an early invasive strategy provides an equivalent outcome when timely primary PCI is not possible; and supports other published experience that early-rescue PCI can be performed safely after administration of PHT. Although PHT can be implemented by trained paramedics working with on-board physicians, the Hunter Region has successfully used paramedics and ECG telemetry in consultation with hospital-based physicians. When the time to open the artery is ≤90 minutes, primary PCI is preferred. When the time to open the artery is >90 minutes, PHT with immediate transport postthrombolysis to a PCI-capable hospital is feasible and effective. CONCLUSIONS PHT delivered by trained paramedics with telemetery backup to assist ECG interpretation is feasible and delivers the prospect of early reperfusion.

PRE-HOSPITAL THROMBOLYSIS VERSUS PRIMARY PERCUTANEOUS CORONARY INTERVENTION FOR ST-SEGMENT ELEVATION MYOCARDIAL INFARCTION IN REGIONAL AUSTRALIA: REAL WORLD LONG TERM FOLLOW UP

Delivering reperfusion therapy to patients with ST-segment elevation myocardial infarction (STEMI) throughout the Hunter New England Local Health District (HNELHD) Australia, which covers 130,000 square kilometres with only one 24/7 cardiac catheterization laboratory (CCL), remains challenging. The

PM211 Pre Hospital Thrombolysis - An Examination of Clinical Outcomes

O ST E R A B ST R A C T S shock and recurrent MI at 30 days. Secondary outcomes include acute kidney injury and bleeding. Results: During the study, 40 STEMIs (22 PAPA and 18 ED) presented to the catheterization lab; 30 (75%) underwent PPCI, 6 (15%) required emergency coronary artery bypass surgery and 5 (12.5%) had non-obstructive coronary disease and treated medically. Of the 30 PPCIs, 19 (47.5%) presented via PAPA and 11 (27.5%) via ED. Patient demographics and vessel characteristics were similar between the two groups. Mean FMCL/FMCB times for the PAPA and ED groups were 41 +/9 vs. 83 +/80 minutes (p1⁄4<0.05) and 76 +/17 vs. 105 +/79 minutes (p1⁄40.29). Clinical follow up at 30 days was available for 39 patients; primary outcomes occurred in 4 (18.2%) PAPA cases and 7 (38.9%) ED cases (p1⁄40.17) with 1 death in the PAPA group and 3 deaths in the ED group. Secondary outcomes occurred in two (9.1%) PAPA cases and seven (38.9%) ED cases (p1⁄40.06). No patient required target vessel revascularization at 30 days. Conclusion: There was a non-significant trend towards less primary and secondary outcomes in the PAPA group associated with significantly shorter FMCL and FMCB times. The novel PAPA program could be a safe and effective method to reduce both lab times and outcomes in PPCI for STEMIs in regional areas of Australia. Disclosure of Interest: None Declared

Corrigendum to “CSANZ Abstracts 2011”: Analysis of ECG to diagnose acute coronary syndrome in pre-hospital setting using computerised algorithm

T authors regret that information originally included in the attached abstract was not up to date. Please see below abstract with up to date information. Introduction Algorithms have been used to improve diagnosis of ischaemia and acute myocardial infarction since the 1970s. In the era of pre-hospital electrocardiogram (ECG) analysis to guide thrombolysis arid percutaneous coronary intervention (PCI), there is greater reliance of ECG interpretation by non expert staff. There is a role for the algorithms such as the Glasgow algorithm to improve interpretation of these ECGs. Aim To assess the Glasgow algorithm in diagnosis of ST elevation myocardial infarction (STEMI) and ischaemia. Method Ambulance units in N fitted with ECG units using the Glasgow algorithm collected ECG’s between January 2010 and January 2011. ECGs were obtained from patients with chest pain and cardiac symptoms, assessed during emergency calls by ambulance. 672 ECGS on 652 patients were recorded and interpreted by units fitted with the Glasgow algorithm were reviewed by two cardiologists. Any discrepancies in interpretation of ECGS between the two cardiologists were discussed and a consensus about the classification reached. Sensitivity and specificity for detection of ST elevation myocardial infarction (STEMI) was then calculated, compared to the interpretation of ECGS by the cardiologists. A qualitative assessment of the cause of differences in classification between cardiologist and algorithm was made. Results Of 652 patients, 206 were identified by the ECG program to have an ST elevation myocardial infarct satisfying criteria for thrombolysis or PCI. Compared with the cardiologists’ interpretation, the algorithm had identified 184 true positive STEMI events, 446 true negative events, 20 false positive events and 3 false negative events. This translates to a sensitivity of 97% and specificity of 95% for identification of STEMI events. Qualitative assessment of traces where there was significant disagreement showed that “overcall” of STEMI was associated with atrial flutter in four cases, Brugada in one case, nine high ST segment takeoff, one case with ventricular tachycardia and the rest due to LBBB particularly with tachycardia as well as RBBB. Inferior infarcts were almost twice as common as anterior infarcts. The Glasgow algorithm identified “possible infarct, age undetermined” in 118 patients, 115 of whom were interpreted by the cardiologists as having an “old infarct”, without ST elevation. There were a handful of multiple ECGs recorded within minutes have shown major changes with ST segments and T wave alterations. Discussion When compared to two cardiologists, the Glasgow algorithm has high sensitivity and specificity for identification of STEMI and ischemia. Some causes of misinterpretations are consistent and the interpretations of ECGs in context of these causes should be treated with caution. These causes include left bundle branch block, right bundle branch block, fluctuations of baseline due to artefacts, and regular arrhythmia such as atrial flutter and ventricular tachycardia. Conclusion The Glasgow algorithm may have a significant role in supporting emergency diagnosis of AMI It is possible that further evaluation, particularly with detailed assessment of the outcome of patients will help in using this tool.