The role of heart rate variability in assessing the evolution of patients with chronic obstructive pulmonary disease.

Chronic obstructive pulmonary disease (CPOD) is an important cause of morbidity and mortality. Cardiovascular involvement is the most common complication of the disease. Abnormalities of autonomic system, caused by this involvement, can lead to cardiac arrhythmias and sudden death. An important tool in assessing the dysfunction of the autonomic nervous system is the measurement of heart rate variability (HRV). In this article we systematically review the literature that addresses the role of heart rate variability as a maker of clinical evolution in patients with COPD. We focused on correlations between heart rate variability and pulmonary, muscular, cognitive and functional impairment. Heart rate variability has proven an important tool in assessing the cardiac function, the respiratory function, the muscular force, the cognitive capacity and the life quality of these patients. Until recently the problem of the cardiac autonomic dysfunction in patients with COPD could be identified only by invasive measures. At present the simple measuring of HRV is used as a noninvasive method in assessing the cardiac problems of these patients. HRV can be correlated with the severity of the disease, knowing that a dysfunction in autonomic nervous system can lead to potential fatal arrhythmias. Understanding the role of HRV in the evolution of COPD could be important in clinical practice and should be used more frequently.