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EBM Jan 8, 2010
Coronary Bypass Surgery with or without Surgical Ventricular Reconstruction
Robert H. Jones, M.D., Eric J. Velazquez, M.D., Robert E. Michler, M.D et al. Surgical Treatment
for Ischemic Heart Failure Investigators
NEJM 2009;360:1705-17.
BACKGROUND
Coronary Artery Disease is leading cause of death and a major cause of disability in the
developed world. After MI up to 26% of patients will develop left ventricular dilation, a
misshaped spherical ventricle with depressed contractile function, as a result of ventricular
remodeling. Post-infarct remodeling of the left ventricle is associated with severe heart failure
and a poor prognosis. ACE-inhibitors and Beta-Blockers, both therapies that influence
ventricular remodeling, are associated with reduced mortality and morbidity in this patient
population. Surgical Ventricular Restoration, or the Dor procedure, was developed to directly
modify the LV, reducing the size, removing akinetic portions.
In the years prior to the STICH trial nonrandomized studies reported that SVR in combination
with coronary revascularization, reduced myocardial dyssynchrony, improved ejection fraction,
reduced hospitalizations, and improved NYHA classification of patients with severe ischemic HF.
In 2004, the RESTORE trial1, a observational study that followed 1198 post infarction patients
from 1998-2002, reported that post SVR patients had increased EF from 29% to 39% and a five
year survival of 68%. In May 2008, Prucz et al published a retrospective case-control study with
120 patients that reported a 50% reduction in hospitalizations and a statistically significant
improvement in NYHA HF classification but similar 4 year survival and LVEF in patients that had
CABG +/- SVR2. Neither of these studies were randomized and only the later included a control.
The STICH trial was the first RCT to investigate SVR+CABG vs CABG alone...
STUDY CHARACTERISTICS
Question: Does SVR Improve Survival and/or HF Symptoms in Patients With Advanced Post
Infarction Ventricular Remodeling?
Primary Outcome3: Long-term survival free of cardiac hospitalization (all cause time to death or
cardiac-cause hospitalization)
Secondary Outcomes: Exercise capacity, Quality of Life, Cost effectiveness
Trial Type: Multi-center, Non-blinded, Randomized Controlled Trial
Inclusion Criteria:
 Symptomatic heart failure defined as NYHA Class II-IV (within 3 months of entry)
 LVEF less than 35%, as defined by echocardiogram, left ventriculogram, or SPECT
 Coronary anatomy amenable for CABG
Exclusion Criteria:
 Clearly defined primary valvular heart disease indicating repair or replacement
 Percutaneous coronary intervention (PCI) planned for CAD treatment
 Acute myocardial infarction within 30 days of study entry
 Non-cardiac illness with life expectancy less than 3 year
Study Participants: After eligibility was determined participants were evaluated for designation
to either of two main wings of study (H1 med management vs CABG excluded pts w LM disease
and H2 CABG +/- SVR).
1
Surgical ventricular restoration in the treatment of congestive heart failure due to post-infarction ventricular dilation. JACC 2004
Oct 6; 44(7):1439-45
2 Coronary Artery Bypass Grafting With or Without Surgical Ventricular Restoration: a Comparison. ATS 2008;86:806-14.
3
http://clinicaltrials.gov/show/NCT00023595

1000 patients were randomly assigned to either receive CABG or CABG+SVR along with
guideline-based medical management/device implantation
Statistical Analysis: Power calculated to detect a 20% reduction in relative risk of death or
hospitalization assuming a three year event rate of at least 45% and allowing for a 20%
crossover rate. All major comparisons included intention to treat analysis. Cumulative event
rates were calculated using the Kaplan-Meier method and hazard ratios derived using the Cox
proportional hazard model.
Strengths: Large trial, randomized, operators required to demonstrate technical proficiency,
good follow up
Weaknesses: Unblinded (participants and surgeons and post–op cardiologists), med
management not tracked/reported longitudinally
Results:
There was no statistically significant difference in the primary outcome. All cause death or
cardiac cause hospitalization occurred in 58% CABG alone and 59% of the CABG+SVR.
There was no statistically significant difference in the secondary outcomes. The 6 min walk
improved on average by 48m in the CABG alone group and by 52m in the CABG+SVR group
(p=0.80).
The authors reported a 19% reduction in end systolic volume in the CABG+SVR. This was a
statistically significant reduction, however it appears to be clinically insignificant.
STUDY VALIDITY
Is there a clearly-focused study question? YES
Was the assignment of patients to treatment random? YES
Were treatment and control groups well balanced? Yes, from the demographic characteristics
appears so. The med management profile was similar the study initiation however the device
placement/med management was not reported over time. Also, the types of procedures
performed may have varied.
Were participants, staff and study personnel “blind” to participants study groups? NO, surgeons
could not be blinded. The cardiologist managing patients could have been blinded but were not
and it is not apparent the patients were blinded as well.
Were all participants who entered the trial accounted for? Predominantly, yes. Only four
patients withdrew consent and only six were lost to follow up. Of the original 1000 patients,
99%completed follow up.
STUDY APPLICABILITY/LESSONS LEARNED
The patient population is similar to many patients that we see on the cardiology service.
This is a well-designed trial that became the definitive statement addressing SVR for advanced
ischemic HF and disproved the prevailing opinion which was based on non-randomized and noncontrolled trials. The studies that supported the unmerited enthusiasm were subject to the
classic errors of non-controlled and nonrandomized trials: selection bias and recall bias.
Selection bias occurs when an unappreciated characteristic of participants influences both their
participation and their outcome in a study. Retrospective studies are also especially vulnerable
to recall bias where the intervention itself may influence or enhance the ability of respondents
to report exposures and outcomes or may encourage/discourage clinical documentation.
Finally, this Is only the first wing of the study, the highly anticipated follow up report is
scheduled to report on a comparison of med management vs CABG in patients with advanced
ischemic HF.