Revascularization In HFrEF: Are We Close To The Truth Ali Almasood
HF epidemic 1-2% of the population have HF At least one-half have heart failure with reduced ejection fraction (HF- REF) The most common etiology of HFrEF is IHD (>65% ) Patients with ischemic causes of left ventricular (LV) systolic dysfunction have significantly higher mortality rates than those with non-ischemic etiologies
Role of CAD in the pathophysiology of HF with reduced systolic function Mihai Gheorghiade et al. Circulation. 2006;114:1202-1213
Ischemic Cardiomyopathy Therapy is multifaceted Revascularization Pharmacological Nonpharmacological. The pharmacological armamentarium focuses on altering the neurohormonal response The nonpharmacological approaches focus on improving electrical synchrony (CRT)
The Goal of Ischemic Cardiomyopathy Therapy Optimize cardiovascular function Prevent progressive remodeling Allay symptoms of heart failure Improve survival
Proposed Definition ischemic CM Impaired LV function ( EF <35%) plus one of the following ; History of MI or revascularization (CABG or PCI) 75% stenosis of left main or proximal LAD 75% stenosis of two or more epicardial vessels Felker et al. Definition of Ischemic Cardiomyopathy JACC Vol. 39, No. 2, 2002
Survival curves for ischemic versus non-ischemic JACC Vol. 39, No. 2, 2002 January 16, 2002:210 8
Survival curves quantifying coronary artery disease (CAD) JACC Vol. 39, No. 2, 2002 January 16, 2002:210 8
Medical therapy The cornerstone of treatment for patients with HFrEF remains guideline-directed medical therapy (GDMT) It is associated with significant improvement in survival and quality of life
Benefits Of Revascularization
A challenging clinical scenario remains: the patient with severe LV dysfunction receiving (OMT) and carrying significant surgical risk. Can we improve symptoms? Can we improve survival? Is there a role for viability testing? Is there a stand alone test, or should different modalities be used complementarily?
SURGICAL REVASCULARIZATION: OBSERVATIONAL REPORTS observational and often drawn from only a single institution from 1960s and 1970s Reductions in mortality with surgery compared with medical therapy ranged from 10% to >50% However, most of these studies either date from the, before the advent of B-blockers and ACEI Alderman ELet al. Results of CABG iwith poor LVF(CASS). Circulation 1983. O Connor CMet al. (a 25-year experience ). Am J Cardiol 2002
TRIALS OF SURGICAL VERSUS PERCUTANEOUS REVASCULARIZATION BARI (Bypass Angioplasty Revascularization Investigation) 22% of patients had LVEF <50% AWESOME (Angina With Extremely Serious Operative Mortality Evaluation) 28% had LVEF <39% SYNTAX trial 2% had LVEF <35% FREEDOM trial (Future Revascularization Evaluation in Patients With DM: Optimal Management of Multivessel Disease) 2.3% had LVEF <40%
Everolimus-eluting stent (EES) vs CABG for the risk of death. Circulation May 31, 2016
Everolimus-eluting stent (EES) vs CABG for the risk of death
THE STICH TRIAL The only prospective, randomized, controlled trial investigate the role of CABG with LVEF 35% who are also receiving GDMT the rate of death of any cause over 10 years was significantly reduced by an absolute difference of 8% in patients who underwent CABG in addition to OMT compared with those receiving optimal contemporary medical therapy alone
Survival Analyses in the STICH Trial Using an Intention-to-Treat Analysis
Survival Analyses in the STICH Trial According to Actual Treatment Received
STICHES TRIAL 10 Y F/U
Myocardial Viability and Mortality (STICHES trial) CABG may be considered for improving survival in patients with ischemic heart disease with severe LV systolic dysfunction (EF <35%), whether or not viable myocardium is present (Class IIb, Level of Evidence: B)
Annual mortality rate in patients with and without myocardial viability treated with revascularization vs medical therapy (Meta-analysis by allman et al) JACC. 2002;39(7):.
Contributing Factors Influencing the Decision for Revascularization in severe HF
MYOCARDIAL VIABILITY Revascularization in patients with significant viability improve outcomes, cardiac function, and functional class in many observational studies Viable myocardium (>20%) in the setting of ventricular dysfunction, mortality increases when the therapeutic strategy is medical therapy alone
Hibernation and Stunning
Range of Sensitivity, Specificity, PPV, and NPV of Currently Available Viability Testing Modalities
Comparison of Imaging Modalities Used to Test Myocardial Viability
Is myocardial viability a viable concept in contemporary clinical practice? Viability testing might: 1) help predict the response to revascularization in selected patients with CAD and LV dysfunction 2) be a marker of prognosis 3) influence response to medical therapy.
Conclusion ICM therapy is multifaceted, including revascularization paralleled with ancillary pharmacological and nonpharmacological strategies Revascularization is considered the gold standard treatment for ICM Guidelines recommend (CABG) over (PCI) for multivessel disease and severe LV dysfunction CABG has not been compared with PCI in such patients in randomized trials
Conclusion The role of viability testing in the setting of ICM still controversial Multimodality imaging could provide deeper insight into the spectrum of myocardial substrate, emphasizing not only the role of revascularization but also neurohormonal modulation and resynchronization therapy The benefit of high-risk procedural interventions is likely to be low