IMAGE-HF Project I-A: Cardiac Imaging in Ischemic Heart Failure (AIMI-HF)

Among patients with coronary artery disease and HF, mortality rates range from 10-60% at 1 year. Many trials have demonstrated benefit of revascularization in patients with ischemic heart disease (IHD) and LV dysfunction. Some criteria, such as severe angina or left main coronary artery stenosis may indicate the need for surgical therapy for HF patients; however, a large number of patients fall into a gray zone without clear evidence for benefit from surgical intervention. The need remains for approaches that can help better define and select the HF patients most likely to benefit from revascularization; which could be either surgical or percutaneous intervention. Increasingly over the past three decades, information describing cardiac structure, perfusion, hemodynamics, and metabolism obtained from noninvasive cardiac imaging studies has been used to guide management decisions for patients with HF. AIMI-HF is part of a large international team grant IMAGE-HF (Imaging Modalities to Assist with Guiding therapy and the Evaluation of patients with Heart Failure) involving 3 parallel trials addressing the role of imaging in HF patients according to HF etiology. Primary Hypothesis of AIMI-HF: In patients with HF due to IHD with LVEF less than or equal to 45%, a management algorithm that applies alternative advanced imaging strategies (PET or CMR) achieves a better clinical outcome measured as the composite clinical endpoint (CCE) of cardiac death, MI, resuscitated cardiac arrest and cardiac re-hospitalization (WHF, ACS, arrhythmia) than an approach with "standard care". Secondary Hypotheses of AIMI-HF: i) Compared to standard care, in patients with HF due to IHD with LVEF ≤ 45%, a management algorithm that applies alternative advanced imaging modalities (PET or CMR) achieves: a) more efficient use of revascularization procedures with similar complication rates than standard care imaging strategies b) better LV remodeling (including favorable evolution of serum markers associated with LV remodeling e.g. PIIINP, OPN) c) better HF and angina symptom reduction, d) better QoL, measured using MLHFQ and EQ5D, e) more favorable evolution of selected serum markers of prognosis in HF (e.g. BNP, RDW, hs-cTnT, hs-CRP), f) is economically attractive in patients with HF due to IHD with LVEF\<45%, g) reduced event rates of each components of composite endpoint; h) all-cause mortality. ii) In patients with HF due to IHD with LVEF ≤ 45%, a HF management algorithm that applies PET or one that applies MRI, achieves a better primary composite clinical endpoint (CCE) and secondary outcomes compared to one that applies standard of care in patients assessed for ischemia and/or in patients assessed for viability. iii) In patients with HF due to IHD with LVEF ≤ 45%, a HF management algorithm that applies PET achieves a better primary composite clinical endpoint (CCE) and secondary outcomes compared to one that applies CMR in patients assessed for ischemia and/or in patients assessed for viability. iii) Renal function impairment is a known independent predictor of cardiovascular events in HF. Renal function may influence revascularization decisions and its evolution could be modified by revascularization procedures. Study design AIMI-HF is the IMAGE-HF Project 1-A trial; it is a prospective comparative effectiveness study to compare the effect of HF imaging strategies in patients with HF due to IHD. Eligible patients will have LV systolic dysfunction due to IHD where evaluation of ischemia or viability is relevant. Patients will be prospectively randomized to standard (SPECT) versus advanced (PET or CMR) imaging. Patients who meet inclusion criteria but cannot be randomized due to clinical management decisions, yet undergo standard or advanced imaging (SPECT, PET/CT or CMR), will be entered into a registry. Based on site screening logs, patients who could not be randomized, who met all other inclusion criteria and underwent standard or advanced imaging, will be retrospectively enrolled, from the date of original HREB approval, into the study as registry participants. Registry recruitment will be monitored to ensure as best as possible a balanced recruitment for each modality registry.