Bobby Heydari

Accelerated cardiac MR stress perfusion with radial sampling after physical exercise with an MR-compatible supine bicycle ergometer

To evaluate the feasibility of accelerated cardiac MR (CMR) perfusion with radial sampling using nonlinear image reconstruction after exercise on an MR‐compatible supine bike ergometer.

Stress CMR myocardial perfusion imaging (CMR-MPI) is cost-effective compared to nuclear SPECT: a retrospective cost-effectiveness analysis

Background Stress CMR myocardial perfusion is a strong risk-stratifying tool increasingly used for patient management. However, the cost-effectiveness of this technique in patients with suspected ischemia, has never been studied against nuclear SPECT. Methods From 2003-2011, 707 patients underwent CMR-MPI for ischemia assessment in our center. Estimated pre-test cardiac risk derived from a combined Framingham Heart Study and Diamond Forrester risk percentage was used to match CMR patients against 39,876 patients who underwent pharmacologic stress SPECT in another tertiary-care center during the same time period. Framingham scoring system for the prediction of cardiovascular risk was also stratified by presence or absence of prior evidence of CAD. A validated computer algorithm was used to perform 1:1 patient risk-matching. For all patients, cardiac events (acute MI/death), angiographically-significant CAD, percutaneous coronary intervention and bypass grafting, repeat stress testing/imaging within 2 years, and cost estimates for these events from national average were collected for cost-effectiveness analysis. One-to-one risk-profile matching between CMR-MPI and SPECT was successful in 704 patients (99.6%). Ischemia by SPECT was positive, negative, and equivocal in 8%, 74%, and 18%, which compared with 22%, 75%, and 3%, respectively by CMR-MPI. A negative SPECT was associated with a 2-year cardiac event rate of 4.6% compared to 1.3% by CMR-MPI (p=0.002). Other items relevant to cost-effectiveness analysis using imaging for “gate-keeping” stratification are shown in Table 1. Conclusions In patients with an intermediate risk of ischemic heart disease, stress CMR myocardial perfusion is cost-effective when compared to pharmacologic stress SPECT. A negative stress CMR perfusion study is associated with a lower 2 year event rate and lower downstream costs.

T1 measurements identify extracellular volume expansion in a genotyped hypertrophic cardiomyopathy population with and without left ventricular hypertrophy

Background Myocardial fibrosis is a hallmark of hypertrophic cardiomyopathy (HCM) and may contribute to arrhythmias and heart failure. Sarcomere mutations appear to induce profibrotic changes before left ventricular hypertrophy (LVH) develops. Measuring T1 relaxation times with contrast cardiac magnetic resonance (CMR) allows robust quantification of the cardiac extracellular volume (ECV) and noninvasive assessment of diffuse myocardial fibrosis. Methods A genotyped HCM population underwent contrast CMR with measurement of T1. Subjects included sarcomere mutation carriers with LVH (G+/LVH+, n = 37) and without LVH (G+/LVH-, n = 30); HCM patients without mutations (sarcomere-negative HCM, n = 11); and mutation-negative healthy controls (n = 10). Concurrent echocardiography and serum biomarkers of collagen synthesis, hemodynamic stress, and myocardial injury were available in a subset. Results Late gadolinium enhancement (LGE) was present in >60% of overt HCM patients but absent from G+/LVHsubjects. Compared to controls, ECV was increased in patients with overt HCM, as well as G+/LVH- mutation

Combined stress myocardial perfusion and late gadolinium enhancement imaging by cardiac magnetic resonance provides robust prognostic information to cardiac events

Background Accurate non-invasive risk stratification may management and impact survival of CAD patients. Stress perfusion CMR reliably assesses ventricular function, viability and myocardial ischemia in a single examination. While prognostic information may be derived from individual components of a comprehensive CMR exam, evidence that they provide complementary prognostic information is still limited. We sought to determine whether the presence of myocardial ischemia by stress perfusion CMR provides incremental prognostic information for major adverse cardiovascular events (MACE) beyond ventricular function, the presence of myocardial scar and traditional risk factors in a large cohort of patients referred for non-invasive assessment of CAD.

ST2 is reduced by high-dose omega-3 fatty acid treatment following acute MI and is correlated with reduction of the extracellular volume fraction of non-infarcted myocardium

ST2 is reduced by high-dose omega-3 fatty acid treatment following acute MI and is correlated with reduction of the extracellular volume fraction of non-infarcted myocardium Bobby Heydari, Shuaib Abdullah, James V Pottala, Ravi V Shah, Siddique A Abbasi, Damien Mandry, Heidi Lumish, Udo Hoffmann, Evan Appelbaum, Jiazuo Feng, Ron Blankstein, Michael Steigner, Joseph P McConnell, William Harris, Michael Jerosch-Herold, Raymond Y Kwong

EFFECT OF PURIFIED OMEGA-3 FATTY ACIDS ON REDUCING LEFT VENTRICULAR REMODELING AFTER ACUTE MYOCARDIAL INFARCTION (OMEGA-REMODEL STUDY: A DOUBLE-BLIND RANDOMIZED CLINICAL TRIAL)

Omega-3 fatty acid (PUFAs) may have a number of beneficial pleiotropic effects. One randomized trial demonstrated significant survival benefit for PUFAs following acute MI. We conducted a randomized, double-blinded, placebo controlled trial of PUFA supplementation post acute MI. 358 patients were

INFARCT TISSUE HETEROGENEITY BY CONTRAST-ENHANCED MRI IS A NOVEL PREDICTOR OF MORTALITY IN PATIENTS WITH CHRONIC CORONARY ARTERY DISEASE AND LEFT VENTRICULAR DYSFUNCTION

Background: Primary prevention of sudden cardiac death (SCD) from coronary artery disease (CAD) focuses on patients with severely reduced left ventricular function although most SCD occurs in patients with only mild or moderate reduction of LV ejection fraction (LVEF). In a consecutive patient cohort with CAD and varying degrees of LV dysfunction, we hypothesized that infarct heterogeneity by cardiac magnetic resonance (CMR) was associated with patient mortality incremental to LVEF. We further examined the strength of this association in CAD patients with LVEF>35%.

Diabetes remains an independent risk factor for adverse remodeling following acute myocardial infarction even with quantification of total infarct size and change in myocardial extracellular volume fraction by CMR

Diabetes remains an independent risk factor for adverse remodeling following acute myocardial infarction even with quantification of total infarct size and change in myocardial extracellular volume fraction by CMR Bobby Heydari, Ravi Shah, Siddique Abbasi, Jiazuo H Feng, Hoshang Farhad, Tomas G Neilan, Ron Blankstein, Rob J van der Geest, Shuaib Abdullah, Sanjeev Francis, Udo Hoffmann, Michael Jerosch-Herold, Raymond Y Kwong

The incidence and prognostic value of silent myocardial scar by late gadolinium enhancement in patients with atrial fibrillation

Background Late gadolinium enhancement (LGE) during contrastenhanced cardiac magnetic resonance (CMR) imaging is a powerful predictor of adverse event. However, there are limited data regarding the incidence and prognostic significance of LGE in patients with atrial fibrillation (AF). Furthermore, while CMR is one of the modalities employed in characterizing pulmonary venous anatomy in patients being considered for radiofrequency ablation therapy, the prognostic significance of an incidental finding of abnormal LGE is unclear. Therefore, our study has 2 aims: 1) to identify the frequency of unanticipated LGE in patients with AF and 2) to determine whether identification of LGE in this population could provide important prognostic information.

Left atrial volume during the early convalescent phase of acute MI is strongly related to expansion of myocardial extracellular matrix during infarct healing and ventricular remodeling

Background Changes in left ventricular compliance caused by diffuse fibrosis after MI may result in diastolic dysfunction and left atrial enlargement. We sought to test the hypothesis that left atrial volume is associated with ECV (a marker of diffuse myocardial fibrosis) during the sub-acute phase of infarction and can predict the increase of ECV during the ensuing months of infarct healing. We quantified left atrial volumes serially in patients after ST-elevation myocardial infarction and assessed their relationship with indices of post-MI remodeling including left ventricular dimensions, ECV, and infarct size. Methods