Blood flow and pressure measurements of right coronary artery to left ventricle fistula.

A case of a dilated and tortuous right coronary artery to left ventricle fistula was surgically repaired. Preoperative intracoronary pressure measurements showed a sudden depression of diastolic pressure in the terminal part of the right coronary artery. Intraoperative mean right coronary flow was recorded as 315 ml/min. After repair of the fistula, blood flow measurements showed only 35 ml/min, which suggested that a large amount of blood was stolen by the fistula. Although systolic and diastolic murmurs only were heard in our patient, continuous murmurs have been noticed by some observers. From a study of the preoperative physical findings, intraoperative coronary flow measurements, and other operative findings, the genesis of heart murmurs relating to this type of anomaly is discussed.