OBJECTIVE: Aorto-pulmonary collaterals (APCs) are frequent in patients with uni-ventricular heart (UVH). Their clinical significance remains controversial and the mechanism that leads to their formation are poor known. Quantitative assessment of APCs blood flow using cardiac magnetic resonance (CMR) has been already validated. Aim: to evaluate the factors associated to APCs flow (QAPCs) assessed by CMR in patients late after Fontan palliation and their impact on cardiac output and clinical outcome. METHODS: Form our CMR database we identified all patients with Fontan intervention who underwent CMR. Patients with a complete set of flow measurements allowing calculation of APC flow were included. QAPCs was calculated using through-plane phase-contrast as QAPCs = (left pulmonary veins flow + right pulmonary veins flow) - (right pulmonary artery flow + left pulmonary artery flow). Values were normalized to body surface area. Medical and surgical history and clinical status, were recorded. Thirty patients underwent also cardiopulmonary test. RESULTS: Sixty-three patients post Fontan palliation were included in the study (35 M, age: 19 ± 9.8). Follow-up from Fontan palliation at CMR study was 12 ± 6.8 years, range: 1-31 years. Median QAPCs was 760 ml/min/m2 (range 106-3000), corresponding to a median 24 % (4-80) of systemic blood flow. QAPCs didn't correlates neither with age at CMR study and at Fontan palliation neither with rest O2 sat, ventricular volumes, ejection fraction and mass. QAPCs was not associated to systemic ventricular type (right, left or 2 complex ventricles), atrial arrhythmias, atrio-ventricular valve regurgitation, or peak oxygen consumption. Meanwhile QAPCs correlates with aortic flow, r= 0.5, P< 0.001 but inversely correlates with "corrected" cardiac output (Aortic flow- QAPCs), r= -0.4, P< 0.001. QAPCs correlates also with LPA area (r= -0.28 P= 0. 01). CONCLUSIONS: New CMR techniques allow reliable quantification of QAPCs. After Fontan palliation QAPCs has a wide range and is associated to reduced left pulmonary area and flow and inversely correlated with "corrected" cardiac output. Although it has been speculated that APC flow adversely affect long-term clinical outcomes, our data dind't support this hypothesis. Further studies are needed to investigate others parameters associated to APCs and could help to improve the indication to APCs embolization.
CMR evaluation of aorto-pulmonary collaterals late after Fontan palliation
L Ait Ali;
2016
Abstract
OBJECTIVE: Aorto-pulmonary collaterals (APCs) are frequent in patients with uni-ventricular heart (UVH). Their clinical significance remains controversial and the mechanism that leads to their formation are poor known. Quantitative assessment of APCs blood flow using cardiac magnetic resonance (CMR) has been already validated. Aim: to evaluate the factors associated to APCs flow (QAPCs) assessed by CMR in patients late after Fontan palliation and their impact on cardiac output and clinical outcome. METHODS: Form our CMR database we identified all patients with Fontan intervention who underwent CMR. Patients with a complete set of flow measurements allowing calculation of APC flow were included. QAPCs was calculated using through-plane phase-contrast as QAPCs = (left pulmonary veins flow + right pulmonary veins flow) - (right pulmonary artery flow + left pulmonary artery flow). Values were normalized to body surface area. Medical and surgical history and clinical status, were recorded. Thirty patients underwent also cardiopulmonary test. RESULTS: Sixty-three patients post Fontan palliation were included in the study (35 M, age: 19 ± 9.8). Follow-up from Fontan palliation at CMR study was 12 ± 6.8 years, range: 1-31 years. Median QAPCs was 760 ml/min/m2 (range 106-3000), corresponding to a median 24 % (4-80) of systemic blood flow. QAPCs didn't correlates neither with age at CMR study and at Fontan palliation neither with rest O2 sat, ventricular volumes, ejection fraction and mass. QAPCs was not associated to systemic ventricular type (right, left or 2 complex ventricles), atrial arrhythmias, atrio-ventricular valve regurgitation, or peak oxygen consumption. Meanwhile QAPCs correlates with aortic flow, r= 0.5, P< 0.001 but inversely correlates with "corrected" cardiac output (Aortic flow- QAPCs), r= -0.4, P< 0.001. QAPCs correlates also with LPA area (r= -0.28 P= 0. 01). CONCLUSIONS: New CMR techniques allow reliable quantification of QAPCs. After Fontan palliation QAPCs has a wide range and is associated to reduced left pulmonary area and flow and inversely correlated with "corrected" cardiac output. Although it has been speculated that APC flow adversely affect long-term clinical outcomes, our data dind't support this hypothesis. Further studies are needed to investigate others parameters associated to APCs and could help to improve the indication to APCs embolization.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
