Background: Chronic obstructive pulmonary disease (COPD) increases the risk of cardiovascular disease 2-3 folds. The factors responsible for this association remain under evaluation. In this study, the prevalence of isolated right ventricular infarction (RVMI) and ischemia were compared with isolated RVMI in other patients. Methods: This observational and analytical case-control pilot study enrolled 100 patients (82 men and 18 women) with suspected exacerbation of COPD hospitalized in the emergency department of No I or Hospital affiliated to Isfahan University of Medical Sciences, Isfahan, Iran from 2003 to 2005. Spirometry was performed with the equipment that met the American Thoracic Society performance criteria. Frequent electrocardiography (including V3R -V4R) and CK-MB enzyme assay were done. Results: Of the 100 patients, 35 (35%) were excluded due to lack of criteria of the study. Echocardiography revealed that all patients with exacerbation of COPD had tricuspid regurgitation about 3-4 m/s, indicating moderate to severe pulmonary hypertension (PH). OF the 65 patients, 6 (9.2%) with moderate to severe pulmonary obstruction had isolated right ventricular myocardial infarction. Also, 9 (13.8%) patients had ST segment depression >= 1 m in V3R and/or V4R. The difference between the patients with and without exacerbation of COPD accompanying isolated RV MI was significant. Conclusion: Increase in the right ventricular pressure reduces the right coronary artery flow which results in ischemia, infraction and circulatory collapse. The results indicate that patients with exacerbation of COPD are at risk of isolated RV ischemia and infarction. Therefore, V3R and V4R lead should be taken.