This document discusses ischemic heart failure syndromes, specifically type IV ischemic heart failure. It provides background on how the author first discovered this syndrome while working in Pakistan in 1995. Type IV ischemic heart failure refers to patients with heart failure symptoms and left ventricular dysfunction but without clear evidence of coronary artery disease as the cause based on conventional criteria. The document discusses several groups of patients that are often overlooked and may have underlying CAD causing their heart failure. These include the very elderly, those with preserved ejection fraction, and those with other comorbidities. It presents a case study of a patient who was initially diagnosed with non-ischemic cardiomyopathy but was ultimately found to have severe three-vessel diffuse CAD on angiogram. The document