Improved cardiovascular MRI using equilibrium phase BT1RESS MR angiography

The National Heart, Lung, and Blood Institute awarded Endeavor Health Clinical Operations $1,553,928 on July 15, 2026, under the Cardiovascular Diseases Research program (CFDA 93.837) to develop and validate equilibrium phase BT1RESS MR angiography for improved cardiovascular imaging.

The award funds a five-year technical development and clinical validation program testing a magnetization-prepared, ECG-gated balanced steady-state free precession pulse sequence that enables high-quality cardiovascular MR angiograms to be obtained during the equilibrium phase of contrast enhancement for tens of minutes after contrast administration, compared to tens of seconds with conventional contrast-enhanced MR angiography. The technique permits reduction of contrast agent dose and delivers improved depiction of arteries, central and systemic veins, and can distinguish slow flow from thrombus. The work addresses a clinical limitation affecting patients who cannot tolerate iodinated contrast agents due to poor renal function and for whom CT angiography is contraindicated. Work will be conducted at two collaborative sites, including Evanston, Illinois, with ultimate completion March 31, 2028. Endeavor Health Clinical Operations, doing business as Evanston Hospital, is a tax-exempt nonprofit hospital system and research institution headquartered in Evanston, Illinois, which receives federal research funding as a prime recipient from NIH component institutes and acts as a sub-recipient on collaborative multi-institutional research grants. The specific aims include testing equilibrium phase BT1RESS in healthy subjects and patients with cardiovascular disease to compare post-contrast time course of blood pool signal, T1 and T2 relaxation, and angiographic image quality.

Abstract

Abstract three-dimensional (3D) contrast-enhanced MR angiography (CEMRA) is a widely-used cross-sectional imaging tool to depict arterial anatomy and detect vascular pathology and is an essential alternative to CT angiography (CTA) for patients who cannot tolerate an iodinated contrast agent due to poor renal function. However, a fundamental limitation of both CTA and CEMRA is that angiographic image quality greatly deteriorates when scans are obtained after the first pass (i.e., during the "equilibrium phase" of contrast enhancement) due to contrast agent dilution. Recently, we described a bright blood brain imaging technique called balanced T1 relaxation-enhanced steady-state (BT1RESS), which consists of a magnetization-prepared, high-bandwidth 3D balanced steady-state free precession pulse sequence. Building on this work, we implemented a 2D- accelerated, ECG-gated version which, for the first time, allows clinically useful equilibrium phase MR angiograms of the cardiovascular system to be obtained using a standard MR contrast agent. With BT1RESS, high-quality angiograms can be obtained during the equilibrium phase for tens of minutes after contrast administration - versus only tens of seconds using conventional CEMRA techniques. Equilibrium phase BT1RESS provides excellent depiction of arteries, central and systemic veins, and can distinguish slow flow from thrombus. Moreover, using BT1RESS will permit the contrast agent dose to be reduced VS. Standard CEMRA. This five-year proposal involving two collaborative sites will test our hypothesis during an initial technical development phase and a subsequent clinical validation phase. Our specific aims are as follows: 1. Test equilibrium phase BT1RESS in healthy subjects and patients with cardiovascular disease to: (a) compare the post-contrast time course of blood pool signal, T1 and T2, and angiographic image quality for a half dose and full dose of contrast agent; (B) optimize scan parameters; (C) maximize scan efficiency, slice coverage, spatial and temporal resolution using advanced 2D acceleration techniques; (D) implement free-breathing whole- chest BT1RESS with