Campodonico Jeness, Bonomi Alice, Alimento Marina, Apostolo Anna, Piotti Arianna, Mattavelli Irene, Salvioni Elisabetta, Mapelli Massimo, Vignati Carlo, Gugliandolo Paola, Pezzuto Beatrice, Grilli Giulia, Rusconi Valentina, Poggio Paolo, Agostoni Piergiuseppe
Centro Cardiologico Monzino, IRCCS, Milan, Italy.
Department of clinical sciences and community health, Cardiovascular section, University of Milan, Milan, Italy.
Int J Cardiol Heart Vasc. 2025 May 1;59:101685. doi: 10.1016/j.ijcha.2025.101685. eCollection 2025 Aug.
Iron deficiency (ID) is frequent in chronic heart failure (HF). Among HF-ID patients those with impaired iron transport (IIT) (Transferrin saturation (TSAT) < 20 %) have the worst prognosis. In HF survival is strictly related to exercise limitation but the link between IIT, exercise limitation and survival is at present undefined.
We evaluated in 999 consecutive patients hospitalized for worsening HF whether IIT affects prognosis through cardiopulmonary exercise test (CPET), i.e. peak oxygen uptake (VO) and ventilation vs. carbon dioxide (VE/VCO) slope. In all patients at stabilization iron metabolism and maximal CPET were performed. Survival was assessed as all cause death, urgent LVAD and heart transplant were considered death equivalents. The causal relationship between survival and IIT, peakVO and VE/VCOslope was assessed applying path analysis.
PeakVO VE/VCOslope and TSAT were 68 ± 44 %pred, 35 ± 9 and 24.4 ± 12.9, respectively. PeakVO and VE/VCOslope were 61 ± 18 vs. 72 ± 53 %pred and 38 ± 10 vs. 33 ± 8, in IIT vs. non IIT patients (p < 0.0001 in both). At univariable and multivariable analysis a correlation between survival and VO, VE/VCOslope and TSAT was observed; at Kaplan-Myer lower peakVO, higher VE/VCOslope and lower TSAT showed worst survival; at path analysis IIT showed both an important effect on survival independent from peakVO and VE/VCOslope (48 %) and an effect on survival independently mediated by VE/VCOslope and peakVO (52 %), contributing to the IIT negative effect on survival.
The adverse impacts of low TSAT on prognosis are in part direct and in part mediated by mechanisms related to reduced peakVO and increased @VE/VCOslope.
缺铁（ID）在慢性心力衰竭（HF）中很常见。在HF-ID患者中，铁转运受损（IIT）（转铁蛋白饱和度（TSAT）<20%）的患者预后最差。在HF中，生存率与运动受限密切相关，但目前IIT、运动受限和生存率之间的联系尚不清楚。
我们在999例因HF恶化而住院的连续患者中评估IIT是否通过心肺运动试验（CPET）影响预后，即峰值摄氧量（VO）和通气与二氧化碳（VE/VCO）斜率。在所有病情稳定的患者中进行铁代谢和最大CPET检查。生存率评估为全因死亡，紧急左心室辅助装置（LVAD）和心脏移植被视为死亡等效情况。应用路径分析评估生存率与IIT、峰值VO和VE/VCO斜率之间的因果关系。
峰值VO、VE/VCO斜率和TSAT分别为预测值的68±44%、35±9和24.4±12.9。IIT患者与非IIT患者的峰值VO和VE/VCO斜率分别为预测值的61±18%与72±53%，以及38±10与33±8（两者p<0.0001）。在单变量和多变量分析中，观察到生存率与VO、VE/VCO斜率和TSAT之间存在相关性；在Kaplan-Myer分析中，较低的峰值VO、较高的VE/VCO斜率和较低的TSAT显示出最差的生存率；在路径分析中，IIT显示出对生存率的重要影响，独立于峰值VO和VE/VCO斜率（48%），以及通过VE/VCO斜率和峰值VO独立介导的对生存率的影响（52%），这导致IIT对生存率产生负面影响。
低TSAT对预后的不利影响部分是直接的，部分是由与峰值VO降低和VE/VCO斜率增加相关的机制介导的。
