Pulmonary Hypertension (PH) related to Left Heart Disease (LHD) is the most common form of PH, accounting for more than two third of all PH cases. The hemodynamic abnormalities seen in PHLHD are complex, and there are currently minimal evidence-based recommendations for the management of PH-LHD. While it is accepted that PH in the context of left heart disease is a marker of worse prognosis, it remains unclear whether its primary treatment is beneficial or harmful. In this article, we discuss the prevalence and significance of PH in patients with Heart Failure (HF) with Reduced Ejection Fraction (HFrEF) as well as HF with Preserved Ejection Fraction (HFpEF), and those with valvular heart disease and provide insights into the complex pathophysiology of cardiopulmonary interrelationship in individuals with PH due to left heart disease. Furthermore, we provide a framework for diagnostic testing and an approach to optimal management of these complex patients based on current European Society of Cardiology (ESC) guidelines.