RESUMO
Either transcranial color-coded Doppler (TCCD) or contrast echocardiography (CE) is the bests of clinically applicable and reproducible methods to evaluate the functionality of right-to-left shunts that can be found in different localization on atrial septum. As the anatomical features of right-to-left shunts could vary in many forms, detection of RLS by functional tests may aid the clinician to do risk prediction and management of patients. Sensitivity of TCDD or CE can be increased by performing effective Valsalva maneuvering during the test procedure. Timing of RLS during the cardiac cycles may help interpreting about the etiology of RLS, atrial septum or intrapulmonary shunts. Intrapulmonary shunts have been recently reported to be associated with RLS and frequently overlooked unless the tests prolonged up to 10th cardiac beat. Migraine, cryptogenic strokes, and paradoxic embolism are closely associated with RLS which should be evaluated by the collaboration of cardiologists and neurologists. Success of diagnostic procedure depends on high suspicion of index for RLS and application of contrast-enhanced tests that are effectively performed at each step.