Coronary artery fistulae are abnormal connections between a coronary artery and any cardiac chamber or other vessels. Most of them have a congenital origin. We report a 60 years old woman referring a history of progressive dyspnea and orthopnea during the last year. A continuous heart murmur was audible in the third and fourth intercostal spaces at the left sternal border. Electrocardiogram was normal and echocardiography showed mild dilation of right cavities and an image suggesting a dilated right coronary artery with flow to right atrium. Coronary angiography was performed, showing a normal left coronary artery and a very large, tortuous right coronary artery with an extensive communication to coronary venous sinus. Surgical treatment was decided and was performed without incidents. The patient is well after five years of follow up.Coronary artery fistulae are abnormal connections between a coronary artery and any cardiac chamber or other vessels. Most of them have a congenital origin. We report a 60 years old woman referring a history of progressive dyspnea and orthopnea during the last year. A continuous heart murmur was audible in the third and fourth intercostal spaces at the left sternal border. Electrocardiogram was normal and echocardiography showed mild dilation of right cavities and an image suggesting a dilated right coronary artery with flow to right atrium. Coronary angiography was performed, showing a normal left coronary artery and a very large, tortuous right coronary artery with an extensive communication to coronary venous sinus. Surgical treatment was decided and was performed without incidents. The patient is well after five years of follow up.