Assessment of Left Ventricular Function in COPD

The anatomical and functional relationship between the heart and lungs is so close that dysfunction of one of these systems can affect the other. There are neurological, humoral and mechanical interactions between both organs, and various mechanisms that lead to structural or functional ventricular alterations can coexist in patients with respiratory disease. Chronic obstructive pulmonary disease (COPD) is a disease state "characterized by the presence of airflow obstruction due to chronic bronchitis or emphysema; the airflow obstruction is progressive and partially reversible". Patients with COPD can have sustained (patients with chronic respiratory failure), or intermittent hypoxia (during exercise, exacerbations, or during sleep). Hypoxia can cause abnormalities in ventricular relaxation and contraction due to changes in the myocyte cell metabolism. It can also affect the pathogenesis of atherosclerosis by various mechanisms, including increased vascular and systemic inflammation, elevated C-reactive protein and increased oxidative stress. Furthermore, it can induce hemodynamic stress by increasing the heart rate and activating the sympathetic nervous system. Finally, hypoxia is involved in pulmonary vascular remodelling that increases pulmonary vascular resistance, which may negatively affect LV diastolic filling by the phenomenon of ventricular interdependence. However, LV ejection fraction by two-dimensional echocardiography can be normal despite LV dysfunction. Because of paradox of the previous published literatures and the symptom similarity between LV function and COPD, there was need to conduct the study to find out the assessment of LV function in the COPD patients.