Ait Ali Lamia, Cadoni Alessandra, Rossi Giuseppe, Keilberg Petra, Passino Claudio, Festa Pierluigi
Institute of Clinical Physiology CNR, Massa, Italy.
Pediatric Cardiology and GUCH Unit, Pediatric Cardiology, Brotzu Hospital, Cagliari, Italy.
Am J Cardiol. 2017 Jun 15;119(12):2069-2072. doi: 10.1016/j.amjcard.2017.03.040. Epub 2017 Mar 29.
The regulation of cardiac output in the Fontan circuit is not completely understood. Systemic-pulmonary collaterals (SPCs) are frequent in patients with univentricular heart, and their clinical significance and management remain controversial. The aims of our study were to identify factors associated with SPCs' flow at late follow-up after Fontan and evaluate the relation between SPCs flow (QSPCs) and the effective cardiac index (CI). From our cardiac magnetic resonance database, we identified all Fontan patients with a complete set of flow measurements allowing calculation of QSPCs and effective CI. QSPCs was calculated as (left pulmonary veins flow + right pulmonary veins flow) - (right pulmonary artery flow + left pulmonary artery flow). Effective CI was calculated as (Aortic flow (QAo) - QSPCs)/BSA. Medical, surgical history, and clinical status were recorded. Sixty-four post-Fontan patients (36 male; mean age 19 ± 10 years) were included in the study. Median QSPCs was 0.7 L/min/m (interquartile [IQ] range 0.386-0.983) accounting for a median of 21% (IQ range 13-28) of aortic flow. The effective CI in our population was 2.4 ± 0.6 L/min/m. QSPCs inversely correlate with left pulmonary artery area (r = -0.37, p = 0.004) and total antegrade pulmonary flow (r = -0.32, p = 0.01). QSPCs correlate with indexed aortic flow (r = 0.6, p <0.001) and inversely correlate with effective CI (r = -0.39, p = 0.002). Effective CI inversely correlates with age at study and age at the Fontan palliation (r = -0.35, p = 0.005, and r = -0.29, p = 0.02, respectively) and positively with ventricular ejection fraction (r = 0.3, p = 0.01). In conclusion, SPCs are common in Fontan patients, correlate inversely with effective CI, and are associated with a reduced antegrade pulmonary flow. In cardiac magnetic resonance evaluation of post-Fontan patients, effective CI should be taken into account rather than the total CI.
Fontan循环中的心输出量调节尚未完全明确。单心室心脏患者中经常出现体肺分流（SPCs），其临床意义和管理仍存在争议。我们研究的目的是确定Fontan术后晚期随访时与SPCs血流相关的因素，并评估SPCs血流（QSPCs）与有效心指数（CI）之间的关系。从我们的心脏磁共振数据库中，我们识别出所有具有完整血流测量值且能计算QSPCs和有效CI的Fontan患者。QSPCs计算为（左肺静脉血流+右肺静脉血流）-（右肺动脉血流+左肺动脉血流）。有效CI计算为（主动脉血流（QAo）-QSPCs）/体表面积（BSA）。记录患者的医疗、手术史和临床状况。64例Fontan术后患者（36例男性；平均年龄19±10岁）纳入研究。QSPCs的中位数为0.7L/min/m（四分位间距[IQ]范围0.386 - 0.983），占主动脉血流中位数的21%（IQ范围13 - 28）。我们研究人群的有效CI为2.4±0.6L/min/m。QSPCs与左肺动脉面积呈负相关（r = -0.37，p = 0.004），与总的顺行性肺血流呈负相关（r = -0.32，p = 0.01）。QSPCs与指数化主动脉血流呈正相关（r = 0.6，p <0.001），与有效CI呈负相关（r = -0.39，p = 0.002）。有效CI与研究时年龄和Fontan姑息手术时年龄呈负相关（分别为r = -0.35，p = 0.005和r = -0.29，p = 0.02），与心室射血分数呈正相关（r = 0.3，p = 0.01）。总之，SPCs在Fontan患者中很常见，与有效CI呈负相关，并与顺行性肺血流减少有关。在Fontan术后患者的心脏磁共振评估中，应考虑有效CI而非总CI。
