Cardiac failure, also known as heart failure, is a clinical syndrome where the heart's ability to pump blood is inadequate to meet the body's needs, leading to symptoms such as dyspnoea, fatigue, and fluid retention. It matters in clinical practice due to its high prevalence, significant morbidity, and mortality, often requiring complex management strategies. A key association is with coronary artery disease, which can lead to myocardial infarction and subsequent heart failure.