When fluid buildup in the lungs occurs, it can cause heart failure under certain circumstances. Fluid accumulation in the lungs is mainly due to various factors, such as infectious and non-infectious factors, which cause a large amount of secretions to exude from the lungs. Excessive fluid accumulation can compress the lung tissue, leading to the development of restricted respiratory function, the formation of hypoxemia and hypercapnia, and triggering respiratory failure. Infectious factors include more severe viral, bacterial, and Mycobacterium tuberculosis infections, which cause a more pronounced inflammatory response in the airway mucosa and restrict ventilation. Non-infectious factors include bronchiectasis, idiopathic diffuse interstitial pulmonary fibrosis, and alveolar protein deposition, all of which can reduce the function of the lungs and exude large amounts of inflammatory secretions that can aggravate fluid accumulation in the lungs, exacerbating respiratory failure and causing damage to cardiac muscle cells, causing varying degrees of ischemia and hypoxia and causing cardiac insufficiency.