BACKGROUND Chronic obstructive pulmonary disease (COPD) is a global issue with smoking being the most important risk factor. Co-existence of both COPD and cardiovascular diseases is very common and has diagnostic, therapeutic and prognostic implications. The cardiac manifestations of chronic obstructive pulmonary disease are numerous. COPD affects pulmonary blood vessels, right ventricle as well as left ventricle leading to the development of pulmonary hypertension, cor pulmonale, right ventricular dysfunction and left ventricular dysfunction. Because cardiac abnormalities clearly contribute to overall morbidity of COPD, an understanding of their role and potential for treatment is vital. The purpose of this study was to evaluate various cardiac manifestations in chronic obstructive pulmonary disease patients and to observe correlation with its severity. METHODS This hospital based observational study was done in Gauhati Medical College and Hospital attending in-patient department (IPD) and out-patient department (OPD) of Department of General Medicine from 1st July 2018 to 30th June 2019. A total of 140 patients were included in this study. RESULTS Majority of the patients were in the age group of 60 - 70 years. Cardiovascular manifestations were most commonly observed in very severe stage of COPD (GOLD IV). Overall, 91 patients had ECG changes. The most common ECG findings were P pulmonale and right ventricular hypertrophy (RVH). Pulmonary arterial hypertension (PAH) and tricuspid regurgitation (TR) were common echocardiography findings. CONCLUSIONS Cardiac manifestations were more prevalent in COPD GOLD III and IV stages and therefore with increasing severity of COPD, occurrence and severity of cardiac complications becomes more prevalent. ECG and echocardiography are essential investigational tools for diagnosing COPD patients with cardiac complications and assessing their severity. However, a prospective study including a larger sample size is required to arrive at a definite conclusion. KEYWORDS COPD, Cardiac manifestations, ECG, Echocardiography, PAH, RVH