Persistent thebesian vessels involving the right and left ventricles leading to coronary steal phenomena and ischemia
Congenit Heart Dis
We report an extremely rare case of thebesian vein microfistulae to both ventricles. A 65-year-old woman, with no major cardiovascular risk factors, presented with multiple episodes of chest pain. The resting electrocardiogram showed T-wave inversion in leads V(1) -V(4). A Dipyridamole myocardial perfusion imaging revealed large and severe inferior defect with complete reversibility. Coronary angiography showed no coronary artery disease. On contrast injection, an exaggerated capillary blush from the distal portions of the right and left coronary artery systems was seen in both ventricles, mimicking the image of ventriculography. This appearance suggests prominent thebesian vessels, a congenital communication between the coronaries and the two ventricles. The clinical relevance of these myocardial sinusoids is still not well established. Although the majority of these fistulas are small in size and with no clinical significance, they can rarely present with chest pain, cardiac arrhythmia, syncope, myocardial infarction, and/or pulmonary hypertension. These fistulae when excessive can cause significant shunting of blood to the ventricles, leading to coronary steal phenomena and ischemia. This phenomenon is facilitated by the low resistance in these microfistulae as opposed to the higher resistance in the normal coronary circulation. Due to the diffuse nature of these microfistulae, neither surgery nor transcatheter therapy is feasible. This condition can only be managed medically; however, it should be noted that vasodilator agents, such as nitrates, can worsen the coronary steal phenomenon. Our patient was treated with ranolazine with significant improvement in her symptoms, which was not reported previously. Multiple coronary artery microfistulae could be an underestimated condition of angina in patient with normal coronaries.