Both 3D models are modeled in the 3D CAD software Rhinoceros. Such 3D models can easily be drawn in any 3D CAD software. It is enough to draw a 2D contour (guide curves), place several cross-sections (curves) on the contour, and then use the Sweep operation to form a 3D surface from the guide curves and the curves that represent the cross-sections.
This 3D heart loops is suitable for making ornaments, jewelry, pendants and the like.