11:05 〜 11:55
[I-OR107-04] フォンタン生理機能下における大動脈肺動脈側副血行発達危険因子の同定
キーワード：Fontan completions、aortopulmonary collaterals、phase-contrast MRI
Objective: To quantify aortopulmonary collateral (APC) flow volume using phase-contrast MR and to assess its impact on ventricular volume and function after Fontan completions, and to identify risk factors for the development of APCs.
Methods and results: 25 patients (mean age 17.3+/-8.2 years) underwent cardiac MRI as part of their routine clinical assessment that included ventricular functional analysis and flow measurements. APC flow volume was calculated by subtracting the blood flow volume through the pulmonary arteries from that through the pulmonary veins. The ratio of pulmonary to systemic blood flow (Qp/Qs) was 1.27+/-0.32. APC flow volume was 0.76 (range; 0.50 to 1.53) L/min/m2. The mean inaccuracies corresponded to 6.3+/-11.9 % of ascending aortic flow. The patient cohort was divided into two groups according to the median APC flow: group 1＜0.45 l/min/m2 and group 2＞0.45 l/min/m2. Group 1 patients had significant smaller ventricular end-diastolic volume (66+/-18 vs. 88+/-24 ml/m2; p=0.003) and -systolic volumes (27+/-13 vs. 42+/-23 ml/m2; p=0.01) whereas ejection fraction (57+/-11 vs. 53+/-16 %; p=0.32) differed not significantly. Qp/Qs was negatively correlated with a younger age at the time of the bidirectional cavopulmonary connections (r=0.55) and positively correlated with the age at the time of the Fontan completions (r=0.69).
Conclusion: APC blood flow can be noninvasively measured in Fontan patients, using MRI. Volume load due to APC flow in Fontan patients affected ventricular dimensions, but did not result in an impairment of ventricular function.
Methods and results: 25 patients (mean age 17.3+/-8.2 years) underwent cardiac MRI as part of their routine clinical assessment that included ventricular functional analysis and flow measurements. APC flow volume was calculated by subtracting the blood flow volume through the pulmonary arteries from that through the pulmonary veins. The ratio of pulmonary to systemic blood flow (Qp/Qs) was 1.27+/-0.32. APC flow volume was 0.76 (range; 0.50 to 1.53) L/min/m2. The mean inaccuracies corresponded to 6.3+/-11.9 % of ascending aortic flow. The patient cohort was divided into two groups according to the median APC flow: group 1＜0.45 l/min/m2 and group 2＞0.45 l/min/m2. Group 1 patients had significant smaller ventricular end-diastolic volume (66+/-18 vs. 88+/-24 ml/m2; p=0.003) and -systolic volumes (27+/-13 vs. 42+/-23 ml/m2; p=0.01) whereas ejection fraction (57+/-11 vs. 53+/-16 %; p=0.32) differed not significantly. Qp/Qs was negatively correlated with a younger age at the time of the bidirectional cavopulmonary connections (r=0.55) and positively correlated with the age at the time of the Fontan completions (r=0.69).
Conclusion: APC blood flow can be noninvasively measured in Fontan patients, using MRI. Volume load due to APC flow in Fontan patients affected ventricular dimensions, but did not result in an impairment of ventricular function.