Phosphorescence lifetime microscopy and contrast-enhanced ultrasound imaging revealed strong left-to-right intraventricular shunt in anesthetized Xenopus laevis.

was uniformly low (25-40 mmHg), with little arteriovenous difference. Right-to-left shunting was minimal (8%), whereas a strong intraventricular left-to-right shunt (47%) maintained threefold greater pulmonary than systemic flow. Although its significance remains to be elucidated, these approaches provide a foundation for advancing shunt research.