Michael Passick

  • Citations Per Year
Learn More
BACKGROUND AND AIM OF THE STUDY A significant proportion of patients with severe valvular aortic stenosis (AS) and preserved left ventricular (LV) systolic function have low transvalvular gradients. The study aim was to determine the mechanisms and outcome of patients with this hemodynamic profile of AS. METHODS Among 1,679 patients who underwent(More)
OBJECTIVES We investigated the cause of the midsystolic drop (MSD) in left ventricular (LV) ejection velocities that are observed with hypertrophic cardiomyopathy (HCM) and severe obstruction. BACKGROUND Dynamic obstruction is an important determinant of symptoms and adverse outcome. The MSD in velocity and flow occurs in patients with gradients >60 mm(More)
BACKGROUND Cardiac hemodynamics affect pulmonary vascular pressure and flow, but little is known of the effects of hemodynamics on lung perfusion at the tissue level. We sought to investigate the relationship between hemodynamic abnormalities in patients with left heart failure and global and regional lung perfusion using lung perfusion quantification by(More)
HYPOTHESES Degree of mitral annular remodeling is directly associated with severity of chronic mitral regurgitation (MR). Mitral annular remodeling occurs in a symmetric fashion, regardless of MR severity. In addition to MR severity, MR mechanism plays a significant role in mitral annular remodeling. BACKGROUND Limited data exists on mitral annular(More)
BACKGROUND Left atrial (LA) size and function reflect left ventricular (LV) hemodynamics. In the present study, we developed a novel method to determine LA circulation transit time (LATT) by MRI and demonstrated its close association with LV filling pressure. METHODS AND RESULTS All subjects were prospectively recruited and underwent contrast-enhanced MR(More)
PURPOSE To evaluate the performance of lung perfusion imaging using two-dimensional (2D) first pass perfusion MRI and a quantitation program based on model-independent deconvolution algorithm. MATERIALS AND METHODS In eight healthy volunteers 2D first pass lung perfusion was imaged in coronal planes using a partial Fourier saturation recovery stead state(More)
Background Left atrial transit time (LATT) has potential to approximate left ventricular end diastolic pressure noninvasively. Small artifacts are often present in the down-slope portion of the time-intensity curve most likely due to poor SNR resulting from relatively low contrast dosing. While easily circumvented by experienced operator the artifact(More)
Methods All participants were prospectively recruited and underwent CMR in a 1.5 T scanner. LVEF < 45% and ≥45% were used to define HFrEF and HFpEF, respectively. Dilated cardiomyopathy was the primary cause for HFrEF. HF status was confirmed with B-type natriuretic peptide (BNP) > 400 pg/ml. Patients with myocardial infarction were excluded. Myocardial(More)
Methods We prospectively enrolled 20 patients with DCM and 8 normal controls. Of the 20 patients with DCM, 10 patients had acute HF, defined as B-type natriuretic peptide (BNP) greater than 400 pg/ml, and the remaining 10 patients were determined to have no acute HF with BNP predominantly < 100 pg/ml. All subjects underwent cardiac MRI using 1.5-T scanner.(More)
Methods Sixty-five normal volunteers aged 23-85 years were carefully screened by history, ECG and echocardiography. All were free of obesity, diabetes, hypertension, cardiovascular and valvular disease. Participants underwent cardiac MRI and echocardiography on the same day. LV structure and global systolic function were assessed using SSFP cine imaging. LV(More)