Antiplatelet versus anticoagulation therapy after extracardiac conduit Fontan: a systematic review and meta-analysis.

The benefits of prophylactic anticoagulation or antiplatelet therapy for patients undergoing extracardiac conduit (ECC) Fontan procedure still are a matter of debate. Through a systematic review and meta-analysis, this study aimed to determine the incidence of thromboembolism among patients undergoing ECC Fontan who received anticoagulation or antiplatelet therapy. Until February 2010, MEDLINE studies describing the incidence of thromboembolic events after ECC Fontan were reviewed. Information on type of drugs and clinical outcome was extracted. The 20 studies analyzed involved 1,075 patients: 220 (20.4%) in the antiplatelet group and 855 (79.5%) in the anticoagulation group. The mean follow-up period ranged from 2 to 144 months. The overall thromboembolism rate was 5.2% (95% confidence interval [CI], 3.8-7%; I(2) = 0%; p(het) = 0.32). The effect of different therapeutic strategies on the occurrence of thromboembolic and bleeding events was analyzed. Interestingly, the anticoagulation therapy compared with the antiplatelet therapy was not associated with a significant reduction in the incidence of overall thromboembolic complications (5% vs 4.5%, respectively; I(2) = 0%; p(het) = 0.80). Only two cases of bleeding were observed among patients receiving anticoagulant therapy at the time of the event. For patients undergoing ECC Fontan, the rate of thromboembolic and bleeding events associated with antiplatelet therapy is similar to that associated with anticoagulation therapy.

Noninvasive quantification of coronary endothelial function by SPECT imaging in children with a history of Kawasaki disease.

PURPOSE: The feasibility of coronary function estimation by single photon emission computed tomography (SPECT) has been recently demonstrated. The aim of this study was to apply SPECT imaging in patients with previous Kawasaki disease (KD) to assess the coronary functional status at long-term follow-up of the acute phase of the disease. METHODS: Sixteen children with a history of KD underwent 99mTc-sestamibi imaging at rest and during the cold pressor test (CPT). Myocardial blood flow (MBF) was estimated by measuring first transit counts in the pulmonary artery and myocardial counts from SPECT images. Coronary endothelial function was expressed as the ratio of the CPT to rest MBF. RESULTS: Six KD patients without coronary artery lesions served as controls and ten with coronary artery aneurysms during the acute phase of the disease were separated into two groups: group 1 (n=4) with regressed and group 2 (n=6) with persistent aneurysm at follow-up. The estimated coronary endothelial function was higher in controls compared to patients with coronary artery aneurysms (2.5±0.3 vs 1.7±0.7, p<0.05). A significant difference in coronary endothelial function among groups was found (F=5.21, p<0.02). Coronary endothelial function was higher in patients of group 1 than in those of group 2 (1.9±0.6 vs 1.4±0.7, p<0.02). CONCLUSION: SPECT may be applied as a noninvasive method for assessing coronary vascular function in children with a history of KD, demonstrating an impaired response to the CPT, an endothelial-dependent vasodilator stimulus. These findings reinforce the concept that coronary endothelial dysfunction may represent a long-term sequela of KD.