Contrast‐Enhanced Cardiac Magnetic Resonance Imaging With a Manganese‐Based Alternative to Gadolinium for Tissue Characterization of Acute Myocardial Infarction

Abstract

Background Late gadolinium enhancement cardiac magnetic resonance imaging is an effective and reproducible method for characterizing myocardial infarction. However, gadolinium‐based contrast agents are contraindicated in patients with acute and chronic renal insufficiency. In addition, several recent studies have noted tissue deposition of free gadolinium in patients who have undergone serial contrast‐enhanced magnetic resonance imaging. There is a clinical need for alternative forms of magnetic resonance imaging contrast agents that are acceptable in the setting of renal insufficiency. Methods and Results Three days after 80 minutes of ischemia/reperfusion of the left anterior descending coronary artery, cardiac magnetic resonance imaging was performed to assess myocardial lesion burden using both contrast agents. Late gadolinium enhancement cardiac magnetic resonance imaging was examined 10 and 15 minutes after contrast injection. Contrast agents were administered in alternating manner with a 2‐ to 3‐hour washout period between contrast agent injections. Lesion evaluation and image processing were performed using Segment Medviso software. Mean infarct size and transmurality, measured using RVP‐001, were not different compared with those measured using late gadolinium enhancement images. Bland‐Altman analysis demonstrated a nominal bias of 0.13 mL (<1% of average total lesion volume) for RVP‐001 in terms of gross infarct size measurement. Conclusions The experimental manganese‐based contrast agent RVP‐001 appears to be an effective agent for assessment of myocardial infarction location, size, and transmurality, and it may be useful as an alternative to gadolinium‐based agents.

Divalent Manganese Complexes as Potential Replacements for Gadolinium-Based Contrast Agents

“…Mn-PyC3A has been described in mouse, rat, baboon, and pig models. 45,[63][64][65][66] Dynamic MRI was used to assess pharmacokinetics in mice. 45 Like GBCAs, Mn-PyC3A provides immediate enhancement of the blood pool but is rapidly eliminated via the kidneys into the urine with a blood half-life of 7.8 ± 3.0 minutes, similar to small Gd-based chelates in mice.…”

“…66 The mass dose of [ 52 Mn]Mn-PyC3A was 0.2 mmol/kg in line with a dose for a general purpose contrast agent, whereas for [ 52 Mn]Mn-DPDP, a dose of 0.01 mmol/kg was used, which was used clinically. Figure 2 shows maximum intensity projection PET images from 1 to 60 minutes postinjection and again after 5 hours, 63 3-4 days, and at 7 days (note the difference in scale for the later time points). The PET images show that [ 52 Mn]Mn-PyC3A is rapidly cleared, predominantly through the kidneys into the bladder with some biliary elimination.…”

“…The solid red line represents linear regression, and the dotted black lines represent the 95% confidence bands of the regression; identity line is dashed black line. Figure adapted from Bonner et al63…”

Integrative Modulation of Magnetic Resonance Transverse and Longitudinal Relaxivity in a Cell-Viable Bimagnetic Ensemble, γ-Fe2O3@ZnFe2O4

“…The separation of paramagnetic species with the aid of various diamagnetic layers is also observed as a contemporary idea to produce efficient relaxivity in hybrid nanosystems . Indeed, superparamagnetic (SPM) nanosystems appear to be a potential candidate for attaining excellent MRI-relaxivity − due to their unique magnetic behavior, which provides superior contrast efficacy. , …”

Mn(ii) complex impregnated porous silica nanoparticles as Zn(ii)-responsive “Smart” MRI contrast agent for pancreas imaging

“…Magnetic resonance imaging (MRI) has already been established as an indispensable diagnostic modality for the early-stage detection of many diseases. 1–6 However, the imaging process is limited by its low sensitivity due to its NMR-based operational technique. The administration of a paramagnetic species (approximately 0.1 mmol kg −1 ), which is known as a contrast agent, has been recognized to mitigate the low-sensitivity issue by producing conspicuous images in a relatively shorter measurement period.…”