MRI study of cryoinjury infarction in pig hearts: i. Effects of intrapericardial delivery of bFGF/VEGF embedded in alginate beads.

The aim of the study was the testing of sustained intrapericardial delivery of vascular growth factors (GFs) from alginate beads on cryoinjury size and perfusion. In domestic pigs (15-20 kg, n = 21), the left ventricular (LV) anterolateral wall of exposed hearts was cryoinjured using an aluminum rod (25 mm o.d.

MRI studies of cryoinjury infarction in pig hearts: ii. Effects of intrapericardial delivery of adipose-derived stem cells (ADSC) embedded in agarose gel.

The purpose was to assess effects of intrapericardially deposited adipose-derived stem cells (ADSC) as a source of angiogenic factors on cryoinjury infarction. To enhance this effect and reduce incorporation of ADSC into tissue, the cells were immobilized in agarose gel patches transplanted onto cryoinjured epicardium. In domestic pigs (15-20 kg) the left ventricular (LV) anterior wall of exposed hearts was cryoinjured using aluminum rod (Φ=25 mm) cooled in liquid nitrogen.

Rhodamine 800 as a near-infrared fluorescent deposition flow tracer in rodent hearts.

We investigated the use of a near-infrared (NIR) fluorescent dye, Rhodamine 800 (Rhod800, λ(exc) = 693 nm, λ(em) > 720 nm) as a flow-dependent molecular tracer for NIR spectroscopy and high-resolution cardiac imaging. Rhod800 accumulates in isolated mitochondria in proportion to the mitochondrial membrane potential (ΔΨ). However, in the intact myocardium, Rhod800 binding is ΔΨ-independent.

NIR spectroscopic imaging to map hemoglobin + myoglobin oxygenation, their concentration and optical pathlength across a beating pig heart during surgery.

The purpose of this paper is to demonstrate that near-infrared (NIR) spectroscopic imaging can provide spatial distribution (maps) of the absolute concentration of hemoglobin + myoglobin, oxygen saturation parameter and optical pathlength, reporting on the biochemico-physiological status of a beating heart in vivo. The method is based on processing the NIR spectroscopic images employing a first-derivative approach. Blood-pressure-controlled gating compensated the effect of heart motion on the imaging.

Fluorescence imaging to quantify the fluorescent microspheres in cardiac tissue.

To quantify the fluorescent microsphere (FM) content in cardiac tissue, which is an indicative of blood flow, fluorescence imaging of both sides of the pig heart slice was employed. Despite the light scattering inside the tissue and contributions from multiple tissue layers to the total emission, it is shown that the fluorescence intensity at any pixel is proportional to the FM content and the fluorescence image may be transformed to the image of the FM concentration. A convenient standard for the emission-FM concentration transformation is proposed.