Heart evaluation means chest rads, cardiac US or both. ECGs are obviously indicated for arrhythmias but are pretty useless for getting definitive information about valves or muscles. If you are faced with a dog or a cat and you want to know whether their heart is a major concern then all (!) you have to work out is whether the left atrium is enlarged or not. If it is not enlarged then, to all intents and purposes, it is not in heart failure (the only exception being a dog with an acute rupture of the chordae tendineae).Here’s a different radiograph of the DCM dog. Look closely at the pulmonary vessels to the cranial lung lobe (A before V: Artery is cranial to Vein). You can see that the pulmonary vein is bigger than the vein (which it shouldn’t be!).