Simultaneous multi-parametric acquisition and reconstruction techniques in cardiac magnetic resonance imaging: Basic concepts and status of clinical development

Abstract

Simultaneous multi-parametric acquisition and reconstruction techniques (SMART) are gaining attention for their potential to overcome some of cardiovascular magnetic resonance imaging’s (CMR) clinical limitations. The major advantages of SMART lie within their ability to simultaneously capture multiple “features” such as cardiac motion, respiratory motion, T1/T2 relaxation. This review aims to summarize the overarching theory of SMART, describing key concepts that many of these techniques share to produce co-registered, high quality CMR images in less time and with less requirements for specialized personnel. Further, this review provides an overview of the recent developments in the field of SMART by describing how they work, the parameters they can acquire, their status of clinical testing and validation, and by providing examples for how their use can improve the current state of clinical CMR workflows. Many of the SMART are in early phases of development and testing, thus larger scale, controlled trials are needed to evaluate their use in clinical setting and with different cardiac pathologies.

Kardiovaskuläre MRT in der Bewertung von Kardiomyopathien – ein aktueller Überblick

“…Die Weiterentwicklung von MRT-Techniken, wie die hochauflösende Bildgebung, Echtzeit-Cine-Bildgebung, 4-D-Flow-MRT, natives Mapping und neue Kontrastmittel erweitern stetig die diagnostischen Möglichkeiten [9]. Mit dem Einsatz von maschinellem Lernen und innovativen multiparametrischen Akquisitions-und Rekonstruktionstechniken (SMART) wird die MRT zunehmend effizienter [10]. Die fortlaufende Integration der MRT in die Routineuntersuchung und ihre zunehmende Bedeutung für die Steuerung interventioneller Verfahren bestärken ihre herausragende und sich ständig weiterentwickelnde Rolle in der modernen Kardiologie.…”

Imaging in translational cancer research

“…SMART is particularly helpful in patients with complicated heart rhythms or with poor compliance during breath-hold instructions 164 . Simultaneous collective acquisition of several MR parameters such as T1 and T1 relaxation time would therefore significantly improve cardiac MRI efficiency 165 . Further new and emerging imaging techniques include electrocardiogram gated double inversion recovery fast spin echo sequences (or “black-blood” sequences), which can more reliably be used for characterization of cardiac masses or detection of cardiac edema due to nulling of blood 166 ; detection of coronary artery disease, as a cardiotoxic effect of cancer-associated therapy with high speed coronary magnetic resonance angiography or ultrafast imaging of the coronary arteries 167 , 168 ; visualization of pulmonary arteries and their implication in oncological disease through 3D pulmonary MR angiography 169 ; and evaluation cardiac flow velocities at high spatial and temporal resolution with four-dimensional flow MRI 170 .…”

MyoFold: Joint myocardial tissue composition and wall motion quantification via a highly folded sequence

“…6,7 To address these limitations, multitasking techniques have been introduced to shorten imaging time and enhance diagnostic capabilities through the coregistered tissue MR properties. 8 Most of the current approaches are designed for simultaneous myocardial T 1 and T 2 mapping. [9][10][11][12][13][14][15][16] Within a single breath-holding scan, these sequences acquire 10 to 12 hybrid T 1 /T 2 -weighted images to ensure robust estimation of T 1 and T 2 .…”

“…To address these limitations, multitasking techniques have been introduced to shorten imaging time and enhance diagnostic capabilities through the coregistered tissue MR properties 8 . Most of the current approaches are designed for simultaneous myocardial T 1 and T 2 mapping 9–16 .…”