Jeff Macemon Waikato Cardiothoracic Unit Coronary-Artery Bypass Surgery in Patients with Ischaemic Cardiomyopathy (STICHES) Surgical Treatment for Ischaemic Heart Failure Extended Study Jeff Macemon Waikato Cardiothoracic Unit

Background “Coronary artery disease is the most common substrate for heart failure in industrialised nations.” CABG has been evaluated for its roll in Angina and MI Many of these studies excluded patients with significant LV impairment STITCH was designed to evaluate the role of CABG in patients with coronary artery disease and LV systolic dysfunction. Hypothesis: CABG plus intensive medical treatment (compared to medical treatment alone) would reduce mortality. 

STICH 5 year outcome

STICH, death from any cause

Stich, composite outcome

stich Hazard ratio for primary outcome with CABG 0.70 (P<0.001) In the “as treated” analysis

STICHES Following the data set from STICH 10 year outcomes CABG + Medical therapy vs Medical therapy alone Ongoing hypothesis “CABG plus Medical therapy would reduce mortality compared to medical therapy alone”

Methodology

Methods Multicenter Non-blinded Randomised 127 Clinical sites in 26 Countries or 99 Clinical sites in 22 Countries

Methods – Inclusion Criteria Coronary artery disease amendable to CABG LV Ejection Fraction < 35% (determined at each enrolling site) > 18 years of age

Methods – Exclusion Criteria (from supplementary appendix – STICH) LMS > 50% ACS Recent MI or cardiogenic shock in prev 72 hours Prev CABG Aortic valvular disease requiring surgery High risk for operative mortality Prev heart, Kidney, Liver, or Lung transplantation Life expenctancy < 3 years Poor medical adherence Childbearing potential

Additional exclusion criteria (from supplementary appendix – STICHES) Failure to provide informed consent Plan for percutaneousintervention of CAD Recent acute MI judged to be an important cause of LV dysfunction History of more than 1 prior coronary bypass operation

Study Protocol – surgical conduct Patients randomised via an interactive telephone voice response system Those assigned to undergo CABG, within 14 days from randomisation Pre-approved CABG Surgeons Provided evidence of >5% mortality with similar patient risk profile Follow up evaluations at discharge, 30 days, 4 monthly for 1 year, 6 monthly thereafter

Study protocol – Medical therapy Lead Cardiologist at each centre responsible for recommending the most appropriate medications and devices based on current guidelines A Medical therapy committee monitored adherence to guidelines

Methods – Endpoints Primary: Secondary: Death from any cause Secondary: death from cardiovascular cause death from any cause or hospitilisation for cardiovascular cause death from any cause or Hospitilisation for heart failure Death from any cause or revascularisation …. Or non fatal MI ….. Or non fatal stroke

Statistical analysis Initially estimated sample of 2,000 followed for 3 years 90% power to detect a 25% reduction in mortality Slow enrolment  modified design Sample size reduced, follow up increased 1,200 patients followed for 5 years Given lack of definite difference, further funding for 10 years followup Allowed for up to 20% crossover without reducing power INTENTION TO TREAT ANALYSIS

Results

Results 1212 Patients 99 Clinical centres 22 Countries July 2002 – May 2007 Median followup 9.8 years 97.9% followup complete

Results (Tables and Diagrams)

Author’s Conclusion The results of the STICH Extended Study support a significant benefit of CABG plus medical therapy over medical therapy alone With respect to death from any cause Among patients with ischaemic cardiomyopathy

Discussion

Strengths of the study Initial study design appears solid Able to show a difference in outcome in both intention to treat and as treated

Limitations of the study Dubious statistics with additional 5 years of followup May have been some data trolling to find further significant outcomes