A Prospective, Multicentre Randomised Controlled Trial Comparing Catheter Ablation Versus Antiarrhythmic Drugs in Patients With Structural Heart Disease Related Ventricular Tachycardia: The CAAD-VT Trial Protocol.

IMPORTANCE: Randomised trials have shown that catheter ablation (CA) is superior to medical therapy for ventricular tachycardia (VT) largely in patients with ischaemic heart disease. Whether this translates to patients with all forms and stages of structural heart disease (SHD-e.g., non-ischaemic heart disease) is unclear. This trial will help clarify whether catheter ablation offers superior outcomes compared to medical therapy for VT in all patients with SHD. OBJECTIVE: To determine in patients with SHD and spontaneous or inducible VT, if catheter ablation is more efficacious than medical therapy in control of VT during follow-up. DESIGN: Randomised controlled trial including 162 patients, with an allocation ratio of 1:1, stratified by left ventricular ejection fraction (LVEF) and geographical region of site, with a median follow-up of 18-months and a minimum follow-up of 1 year. SETTING: Multicentre study performed in centres across Australia. PARTICIPANTS: Structural heart disease patients with sustained VT or inducible VT (n=162). INTERVENTION: Early treatment, within 30 days of randomisation, with catheter ablation (intervention) or initial treatment with antiarrhythmic drugs only (control). MAIN OUTCOMES, MEASURES, AND RESULTS: Primary endpoint will be a composite of recurrent VT, VT storm (≥3 VT episodes in 24 hrs or incessant VT), or death. Secondary outcomes will include each of the individual primary endpoints, VT burden (number of VT episodes in the 6 months preceding intervention compared to the 6 months after intervention), cardiovascular hospitalisation, mortality (including all-cause mortality, cardiac death, and non-cardiac death) and LVEF (assessed by transthoracic echocardiography from baseline to 6-, 12-, 24- and 36-months post intervention). CONCLUSIONS AND RELEVANCE: The Catheter Ablation versus Anti-arrhythmic Drugs for Ventricular Tachycardia (CAAD-VT) trial will help determine whether catheter ablation is superior to antiarrhythmic drug therapy alone, in patients with SHD-related VT. TRIAL REGISTRY: Australian New Zealand Clinical Trials Registry (ANZCTR) TRIAL REGISTRATION ID: ACTRN12620000045910 TRIAL REGISTRATION URL: https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=377617&isReview=true.

ST-elevation myocardial infarction in a migrant population: a registry-based study of patient treatment and outcomes.

BACKGROUND: Internationally, a growing number of studies has identified race-related disparities in the presentation, treatment and outcomes of patients with ST-elevation myocardial infarction (STEMI). With a large migrant population, Australia presents a unique microcosm in which to study the impact of migrant status and ethnicity in STEMI patients. AIM: To investigate if first-generation migrants differed in presentation, treatment or outcomes following STEMI compared with the Australian-born population. METHODS: We conducted a retrospective observational study using data from a clinician-initiated registry. The study involved 2154 patients who presented to 12 hospitals between 2004 and 2012. Our main outcome measures included time to reperfusion, 30-day mortality and complications. RESULTS: Migrants (n = 1035, 48.8%) were more likely to be older (61 vs 58 years, P < 0.001), diabetic (29.3 vs 21.5%, P < 0.001) and have a prolonged symptom to door time (102 vs 91 min, P = 0.04). Despite lower rates of previous known ischaemic heart disease (22.5 vs 26.6%, P = 0.03), migrants had more diffuse disease (triple vessel or left main (3VD/LM): 29.8 vs 22.0%, P < 0.001) and higher troponin values (3.77 vs 3.22 µg/L, P = 0.01). We found no significant differences in hospital treatment times, intervention types or rates. Multivariate regression identified age, diabetes, female gender and multi-vessel disease as predictors of complications and death at 30 days. CONCLUSIONS: Migrants had longer pre-hospital delays and exhibited different cardiovascular risk profiles than Australian-born patients but received comparable treatment in the acute hospital setting. Higher rates of diabetes and multi-vessel coronary artery disease were seen among migrant patients, indicating a relatively higher risk population.

Economic evaluation of a randomised trial of early return to normal activities versus cardiac rehabilitation after acute myocardial infarction.

BACKGROUND: Although there have been a number of economic evaluations of cardiac rehabilitation after acute myocardial infarction (AMI), none has considered only low-risk patients or control groups with no rehabilitation at all. METHODS: An economic evaluation was included in a randomised controlled trial of patients following uncomplicated AMI. Eligible patients were randomised to return to normal activities after 6 weeks of standard rehabilitation (REHAB, n = 70) or to early return to normal activities 2 weeks after AMI with no formal rehabilitation (ERNA, n = 72). Outcomes were assessed weekly for 6 weeks, then 3, 6 and 12 months post-AMI. Outcomes included four quality of life (QOL) measures (physical abilities, distress, usual/social activities, self-care) and four measures of return to normal activities (paid and unpaid return to any work and to pre-AMI level of work). Statistical analysis included repeated-measures regression (QOL outcomes) and survival analysis (work outcomes). RESULTS: There were no statistically significant differences between the two groups in any of the outcomes measured or in the use of other health services. The net cost that could be saved by the health service by targeting rehabilitation to high-risk patients was approximately $300 (Australian, 1999) per low-risk patient. CONCLUSIONS: Early return to normal activities without formal rehabilitation is cost-effective for low-risk patients.