Thermal pad in LED design
If the &quot;H&quot; region is electrically isolated (at ground potential, or not connected to any voltage), then use several vias to connect it to an underlying (opposite side) GROUND PLANE to dump the heat.
A via with 1:1 ratio of periphery_to_height has 70 degree C per watt Thermal Resistance, using standard PCB foil (1.4 mils thick, or 35 microns, 1 ounce per square foot) and assuming the Via hole interior is also plated to 1.4 mils.
In 1/16th inch PCB stock, that via would be 1/16 height and 1/48 in diameter.
If you used 5 of those vias, the thermal resistance would be 70/5 = 14 degree C per watt, and your LED should last much longer.