Importance of direct right-to-left shunt as high-risk patent foramen ovale associated with cryptogenic stroke.

BACKGROUND: Because transcatheter closure of patent foramen ovale (PFO) has become effective for preventing cryptogenic stroke (CS), it is necessary to determine high-risk PFO associated with CS. This study aimed to clarify the importance of direct right-to-left (RL) shunt through the PFO for identifying high-risk PFO. METHODS: We analyzed 137 patients with and without CS who were confirmed to have PFO. The timing of RL shunt through the PFO was evaluated by cardiac cycles after right atrium (RA) opacification on saline contrast transesophageal echocardiography. Direct RL shunt was defined as microbubbles crossing the PFO before and at the same time of RA opacification. RESULTS: Cardiac cycles of microbubbles crossing the PFO were shorter in patients with CS than in those without CS (2.0 ± 2.2 vs .5 ± 1.1, p < 0.01). Direct RL shunt was more frequently observed in patients with CS than in those without CS (77% vs 29%, p < 0.01), with a sensitivity of 79% and a specificity of 71% for the association with CS. Multivariate analysis revealed that direct RL shunt was related to atrial septal aneurysm and low-angle PFO. Regarding functional features of PFO, the detection rate of CS was 50% for large RL shunt alone, and was increased to 83% when direct RL shunt was added. CONCLUSION: Direct RL shunt was associated with CS and had the incremental value in detecting PFO associated with CS for large RL shunt. The timing of RL shunt can be valuable for identifying high-risk PFO.

The impact of pulmonary artery banding and cardiac resynchronization therapy for the adult patient with congenitally corrected transposition of the great arteries.

It has been controversial how to manage severe dysfunction of the systemic right ventricle and severe tricuspid regurgitation for adult patients with congenitally corrected transposition of the great arteries. We reported a 43-year-old man with these disorders, who received pulmonary artery banding and cardiac resynchronization therapy without cardiopulmonary bypass. The degree of the tricuspid regurgitation was improved to mild-moderate and systemic right ventricular ejection fraction was improved from 28 to 45% after surgery. Cardiopulmonary exercise testing showed that the predictive value of anaerobic threshold and peak oxygen uptake improved from 65 to 99% and 59 to 92%, respectively. In conclusion, pulmonary artery banding and cardiac resynchronization therapy can be the first choice of surgery for severe tricuspid regurgitation with severely impaired systemic right ventricular function. After improving systemic right ventricular dysfunction tricuspid surgery could be the next choice as a surgical intervention in the future.