Prognostic Value Of LV Diastolic Function Assessed By Cardiac Magnetic Resonance In Patients With AL Cardiac Amyloidosis

Objective:To evaluate the diastolic function and investigate the prognostic value of diastolic function in patients with light-chain cardiac amyloidosis(AL-CA),cardiac magnetic resonance imaging feature tracking(CMR-FT)technique was used to measure parameters reflecting diastolic function.Methods:We constantly enrolled patients with AL-CA who underwent CMR between January 2014 and September 2018,and referred to West China Hospital SichuanUniversity.The eligible patients were followed up consecutively until December 2021.The end-point was a composite of all-cause mortality.Twenty-five healthy subjects were elected and served as control group.Function,strain,and strain rate analysis were performed on Medis Suite.Diastolic function parameters including left ventricular early diastolic global longitudinal strain rate(eGLSR),late diastolic global longitudinal strain rate(aGLSR),early diastolic global circumferential strain rate(eGCS),late diastolic global circumferential strain rate(aGCSR),left atrial volumes index(LAVi),ejection fraction(LAEF),longitudinal strain(LS)and strain rate(LSR)corresponding to the reservoir,conduct,contractile booster-pump function were measured.According to the distribution,all diastolic function parameters were compared using One-way ANOVA analysis or Kruskal-Wallis rank sum test followed by post hoc pairwise comparisons with Bonferroni correction.All participants were defined as three groups:AL-CA patients without end-point events(group A),AL-CA patients who reached the end-point(group B)and control subjects(group C).The correlation between variables were assessed by using the Pearson correlation coefficient(r value)or Spearman rank correlation(rsvalue).Cox-regression models and Kaplan-Meier curve were used to investigate the association between diastolic dysfunction and all-cause mortality.Intra-and interobserver variability was tested by using intraclass correlation coefficient.Two-sided P values less than.05 were considered to indi-cate statistical significance.Results:Seventy-seven patients with AL-CA aged 57.8±11.1 were constantly enrolled and followed up consecutively until December 2021,53 patients reached all-cause mortality.All diastolic function parameters were significantly lower in group B than those in group C(all P<0.05).Compared with those patients without end-point events,aGLSR(group A vs group B:0.49±0.22 vs 0.31±0.18,P<0.05)and all diastolic function parameters which derived from LA reservoir,conduit,booster-pump function(except for LSRconduit)were significantly decreased in sub-group B(all P<0.05).Multivariable Cox-regression model and Kaplan-Meier analysisdemonstrated that impairedaGLSR and LAEFreservoir(aGLSR less than 0.34 per second,LAEFreservoir less than 26.12%)were respectively associated with a greater rate of all-cause death(aGLSR hazard ratio,0.07[95%CI:0.01-0.51];p<0.05,LAEFreservoir hazard ratio,0.97[95%CI:0.95-0.10],p<0.05)after adjusting for BSA and Mayo biomarker stage 2004.Conclusions:Diastolic function was impaired in AL-CA patients,and the impaired LV aGLSR and LAEFreservoir derived from cardiac MRI feature tracking strain analysis respectively haveimportant implications for predicting all-cause mortality in patients with light-chain cardiac amylodiosis.