Single-photon emission computed tomography as a fundamental tool in evaluation of myocardial reparation and regeneration therapies

Abstract

Despite unquestionable progress in interventional and pharmacologic therapies of ischemic heart disease, the number of patients with chronic ischemic heart failure is increasing and the prognosis remains poor. Repair/restoration of functional myocardium through progenitor cell-mediated (PCs) healing and renovation of injured myocardium is one of the pivotal directions in biomedical research. PCs release numerous pro-angiogenic and anti-apoptotic factors. Moreover, they have self-renewal capability and may differentiate into specialized cells that include endothelial cells and cardiomyocytes. Uptake and homing of PCs in the zone(s) of ischaemic injury (i.e., their effective transplantation to the target zone) is an essential pre-requisite for any potential therapeutic effect; thus effective cell tracking is fundamental in pre-clinical and early clinical studies. Another crucial requirement in rigorous research is quantification of the infarct zone, including the amount of non-perfused and hypo-perfused myocardium. Quantitative and reproducible evaluation of global and regional myocardial contractility and left ventricular remodeling is particularly relevant in clinical studies. Using SPECT, our earlier work has addressed several critical questions in cardiac regenerative medicine including optimizing transcoronary cell delivery, determination of the zone(s) of myocardial cell uptake, and late functional improvement in relation to the magnitude of cell uptake. Here, we review the role of single-photon emission computed tomography (SPECT), a technique that offers high-sensitivity, quantitative cell tracking on top of its ability to evaluate myocardial perfusion and function on both cross-sectional and longitudinal bases. SPECT, with its direct relevance to routine clinical practice, is a fundamental tool in evaluation of myocardial reparation and regeneration therapies.

Transcoronary stem cell transfer and evolution of infarct-related artery atherosclerosis: evaluation with conventional and novel imaging techniques including Quantitative Virtual Histology (qVH)

“…This is important because the transcoronary route plays a fundamental role in administration of cell-based therapies to compromised myocardium. In particular, as demonstrated by labelled cell myocardial uptake studies [ 11 , 12 , 33 ], this route is mostly effective (with its efficacy degree related to the delivery techniques and cell types). Easiness to use and a good safety-and-feasibility to efficacy balance are important clinical advantages.…”

Acute myocardial infarction reparation/regeneration strategy using Wharton’s jelly multipotent stem cells as an ‘unlimited’ therapeutic agent: 3-year outcomes in a pilot cohort of the CIRCULATE-AMI trial

“…SPECT was performed using a Siemens Symbia T16 SPECT/CT machine. End-diastolic and end-systolic volume, stroke volume (SV), and ejection fraction of the left ventricle (LV) were calculated using quantitative gated SPECT (99mTc-sestamibi) [ 24 ].…”

Infarct size and long-term left ventricular remodelling in acute myocardial infarction patients subjected to transcoronary delivery of progenitor cells

“…Myocardial uptake of the labelled CD34 + CXCR4 + cells was assessed 1 h after transcoronary cell implantation by whole-body planar γ-camera scan. Cell uptake was quantified by the number of counts in the cardiac region of interest in relation to total counts on whole-body images [ 24 , 26 ].…”