Hemodynamic response of the aortic valve during dobutamine onset then progressive aortic banding.

An increasing number of procedures over the past two decades for aortic stenosis (AS) reflects the combination of an aging population and less invasive transcatheter options. As a result, the hemodynamics of the aortic valve (AV) have gained renewed interest to understand its behavior and to optimize patient selection. We studied the hemodynamic relationship between pressure loss (ΔP) and transvalvular flow (Q) of the normal AV as well as the impact of a variable supravalvular stenosis.

Quantitative myocardial perfusion in liver transplantation candidates: Poorly metabolized caffeine inhibition of vasodilatory stress.

Background: Data on cardiac positron emission tomography (PET) in liver transplantation (LT) candidates are limited with no prior study accounting for poorly metabolized caffeine reducing stress perfusion.

Method: Consecutive LT candidates (n = 114) undergoing cardiac rest/stress PET were instructed to abstain from caffeine for 2 days extended to 5 and 7 days. Due to persistently high prevalence of measurable blood caffeine after 5-day caffeine abstinence, dipyridamole (n = 41) initially used was changed to dobutamine (n = 73).

Coronary flow capacity and survival prediction after revascularization: physiological basis and clinical implications.

Background And Aims: Coronary flow capacity (CFC) is associated with an observed 10-year survival probability for individual patients before and after actual revascularization for comparison to virtual hypothetical ideal complete revascularization.

Methods: Stress myocardial perfusion (mL/min/g) and coronary flow reserve (CFR) per pixel were quantified in 6979 coronary artery disease (CAD) subjects using Rb-82 positron emission tomography (PET) for CFC maps of artery-specific size-severity abnormalities expressed as percent left ventricle with prospective follow-up to define survival probability per-decade as fraction of 1.0.