Molecular Imaging to Monitor Left Ventricular Remodeling in Heart Failure

Abstract

Purpose of Review Cardiovascular diseases are the leading cause of deaths worldwide. Many complex cellular and molecular pathways lead to myocardial remodeling after ischemic insults. Anatomy, function, and viability of the myocardium can be assessed by modern medical imaging techniques by both visualizing and quantifying damages. Novel imaging techniques aim for a precise and accurate visualization of the myocardium and for the detection of alternations at the molecular level. Recent Findings Magnetic resonance imaging assesses anatomy, function, and tissue characterization of the myocardium noninvasively with high spatial resolution, sensitivity, and specificity. Using hyperpolarized magnetic resonance imaging, molecular and metabolic conditions can be assessed non-invasively. Single photon-emission tomography and positron-emission tomography are the most sensitive techniques to detect biological processes in the myocardium. Cardiac perfusion, metabolism, and viability are the most common clinical targets. In addition, molecular-targeted imaging of biological processes involved in heart failure, such as myocardial innervation, inflammation, and extracellular matrix remodeling, is feasible. Summary Novel imaging techniques can provide a precise and accurate visualization of the myocardium and for the detection of alternations at molecular level.

Quantification correction for free-breathing myocardial T1ρ mapping in mice using a recursively derived description of a T1ρ* relaxation pathway

“…This leads to a tortuous prospective trigger procedure, which has to be completed by suitable respiratory gating. According to the literature [ 38 ], T 1ρ mapping has rarely been carried out in small animal studies [ 39 – 41 ]. Musthafa et al [ 39 ] presented a study in a mouse infarction model, accounting a significant increase of T 1ρ at day 7 after infarction.…”

Quantification of myocardial fibrosis using noninvasive T2‐mapping magnetic resonance imaging: Preclinical models of aging and pressure overload

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