<prompt> Most common of aery involved in MILADRCALCXDiagonal branch of LAD  <response>: Acute occlusion of the proximal left anterior descending LAD aery is the cause of 40 to 50 of all MIs and typically results in infarction of the anterior wall of the left ventricle, the anterior two thirds of the ventricular septum, and most of the hea apex; more distal occlusion of the same vessel may affect only the apex. Similarly, acute occlusion of the proximal left circumflex LCX aery seen in 15 to 20 of MIs will cause necrosis of the lateral left ventricle, and proximal right coronary aery RCA occlusion 30 to 40 of MIs affects much of the right ventricle. Robbins basic pathology,9th edition,pg no.378 