Objective:To explore the value of cardiac magnetic resonance imaging (CMR) derived left ventricular late gadolinium enhancement (LV LGE) for the primary prevention of malignant ventricular arrhythmias in arrhythmogenic right ventricular cardiomyopathy (ARVC) patients.Methods:This was a single-center retrospective study. Consecutive ARVC patients who underwent CMR at Fuwai Hospital between January 2016 and September 2020, with no history of malignant ventricular arrhythmias at diagnosis, were enrolled. Clinical data and CMR characteristics were collected. The primary endpoint was defined as new-onset malignant ventricular arrhythmias related events, including sustained ventricular tachycardia, ventricular fibrillation/flutter, sudden cardiac death, cardiac arrest, and appropriate implantable cardioverter-defibrillator discharge. Follow-up via telephone interviews and medical records was conducted to confirm endpoint occurrences, and patients were categorized into event-free and event groups based on endpoint status. Univariable and multivariable Cox regression analysis were performed to identify independent risk factors for malignant ventricular arrhythmias in ARVC patients. Subgroup analyses were conducted based on the ARVC 5-year risk score (cutoff: 25%) and the median value of LV LGE percentage (cutoff: 13%). Kaplan-Meier curves were plotted, and log-rank tests were used to compare the difference in the incidence of primary endpoint events between subgroups. Receiver operating characteristic curves and likelihood ratio test were used to evaluate the incremental prognostic value of LV LGE percentage beyond the ARVC 5-year risk score.Results:A total of 172 ARVC patients were enrolled, aged (39.0±16.6) years, including 73 females (42.4%). During a follow-up of 53.1 (25.4, 76.9) months, 51 patients (29.7%) experienced malignant ventricular arrhythmias related events, including 3 cases of sudden cardiac death, 1 cardiac arrest, 33 sustained ventricular tachycardia and 14 appropriate implantable cardioverter-defibrillator discharges. Multivariable Cox regression analysis indicated that the ARVC 5-year risk score ( HR=1.028, 95% CI 1.015-1.041, P<0.001) and LV LGE percentage ( HR=1.059, 95% CI 1.032-1.087, P<0.001) were independent risk factors of the primary endpoint events. Kaplan-Meier analysis using composite stratification (ARVC 5-year risk score cutoff: 25%; LV LGE percentage cutoff: 13%) demonstrated that patients with both high risk scores (≥25%) and extensive LV LGE (≥13%) had the highest risk of primary endpoint events. Notably, among patients with ARVC 5-year risk scores <25%, those with LV LGE≥13% had a higher incidence of primary endpoint events than those without (log-rank P=0.037). The composite prediction model combining the 5-year risk score and left ventricular LGE percentage demonstrated significantly improved predictive performance (area under the curve ( AUC)=0.82, 95% CI 0.75-0.90; likelihood ratio test all P<0.001) compared to single-variable models (left ventricular LGE percentage alone: AUC=0.71, 95% CI 0.63-0.82, P=0.01; 5-year risk score alone: AUC=0.71, 95% CI 0.62-0.81, P=0.02). Conclusion:LV LGE percentage independently predict new-onset malignant ventricular arrhythmias in ARVC patients and provided incremental prognostic value based on the existing ARVC 5-year risk score.

Objective:To explore the value of cardiac magnetic resonance imaging (CMR) derived left ventricular late gadolinium enhancement (LV LGE) for the primary prevention of malignant ventricular arrhythmias in arrhythmogenic right ventricular cardiomyopathy (ARVC) patients.Methods:This was a single-center retrospective study. Consecutive ARVC patients who underwent CMR at Fuwai Hospital between January 2016 and September 2020, with no history of malignant ventricular arrhythmias at diagnosis, were enrolled. Clinical data and CMR characteristics were collected. The primary endpoint was defined as new-onset malignant ventricular arrhythmias related events, including sustained ventricular tachycardia, ventricular fibrillation/flutter, sudden cardiac death, cardiac arrest, and appropriate implantable cardioverter-defibrillator discharge. Follow-up via telephone interviews and medical records was conducted to confirm endpoint occurrences, and patients were categorized into event-free and event groups based on endpoint status. Univariable and multivariable Cox regression analysis were performed to identify independent risk factors for malignant ventricular arrhythmias in ARVC patients. Subgroup analyses were conducted based on the ARVC 5-year risk score (cutoff: 25%) and the median value of LV LGE percentage (cutoff: 13%). Kaplan-Meier curves were plotted, and log-rank tests were used to compare the difference in the incidence of primary endpoint events between subgroups. Receiver operating characteristic curves and likelihood ratio test were used to evaluate the incremental prognostic value of LV LGE percentage beyond the ARVC 5-year risk score.Results:A total of 172 ARVC patients were enrolled, aged (39.0±16.6) years, including 73 females (42.4%). During a follow-up of 53.1 (25.4, 76.9) months, 51 patients (29.7%) experienced malignant ventricular arrhythmias related events, including 3 cases of sudden cardiac death, 1 cardiac arrest, 33 sustained ventricular tachycardia and 14 appropriate implantable cardioverter-defibrillator discharges. Multivariable Cox regression analysis indicated that the ARVC 5-year risk score ( HR=1.028, 95% CI 1.015-1.041, P<0.001) and LV LGE percentage ( HR=1.059, 95% CI 1.032-1.087, P<0.001) were independent risk factors of the primary endpoint events. Kaplan-Meier analysis using composite stratification (ARVC 5-year risk score cutoff: 25%; LV LGE percentage cutoff: 13%) demonstrated that patients with both high risk scores (≥25%) and extensive LV LGE (≥13%) had the highest risk of primary endpoint events. Notably, among patients with ARVC 5-year risk scores <25%, those with LV LGE≥13% had a higher incidence of primary endpoint events than those without (log-rank P=0.037). The composite prediction model combining the 5-year risk score and left ventricular LGE percentage demonstrated significantly improved predictive performance (area under the curve ( AUC)=0.82, 95% CI 0.75-0.90; likelihood ratio test all P<0.001) compared to single-variable models (left ventricular LGE percentage alone: AUC=0.71, 95% CI 0.63-0.82, P=0.01; 5-year risk score alone: AUC=0.71, 95% CI 0.62-0.81, P=0.02). Conclusion:LV LGE percentage independently predict new-onset malignant ventricular arrhythmias in ARVC patients and provided incremental prognostic value based on the existing ARVC 5-year risk score.

Humans ; Amyloidosis ; Amyloid ; Cardiomyopathies

Humans ; Neoplasms, Second Primary/epidemiology* ; Neoplasms/epidemiology* ; Risk Factors ; Prognosis

Objective:To explore the clinical value of cardiac MR (CMR) compression sensing (CS) ultrafast cine sequence in evaluating left and right ventricular systolic function by comparing with traditional segmented acquisition cine sequence (Seg).Methods:Twenty-seven patients with various heart disease were prospectively included. Seg, breath holding CS (bhCS) and free breathing CS (fbCS) covering the left and right ventricles using multi slices in short axis were performed in random order. Friedman test was used to evaluate the overall image quality (grade 1-5 score), blood pool myocardial signal ratio (BMC) and edge sharpness under different methods. Biventricular end diastolic volume (EDV), end systolic volume (ESV), stroke volume (SV), ejection fraction (EF) and left ventricular myocardial mass (Mass) were measured for all three methods. The agreements of the functional measurements between bhCS and Seg (gold standard), and between fbCS and Seg were analyzed by Bland-Altman, and the correlation test was performed.Results:Twenty-four patients with diagnostic images(overall image quality score≥2) for all three methods were included in further analysis. The total imaging time of Seg, bhCS and fbCS decreased successively[375.0 (332.0, 405.6) vs. 50.0 (47.8, 53.7) vs. 20.0 (17.8, 23.7) s, χ 2=48.00, P<0.001]. The overall image quality of fbCS was slightly lower than that of Seg ( Z=-2.67, P=0.023), and there was no difference between Seg and bhCS ( Z=-1.44, P=0.447), bhCS and fbCS ( Z=1.23, P=0.660). There were no differences in edge sharpness (χ 2=1.08, P=0.582) and BMC (χ 2=0.58, P=0.747) for three methods. Bland-Altman polts showed good agreement for biventricular functional measurements between bhCS and Seg, and between fbCS and Seg. All functional measurements of bhCS and fbCS were highly correlated with that of seg ( r>0.96, P<0.001). Conclusions:Compared with traditional sequences, CS ultrafast cine sequences can save scanning time and provide similar image quality. No matter whether breath holding or not, the cardiac functional results of CS sequence and traditional cine sequence have good agreement and high correlation.

Objective:To investigate the value of T 1ρ mapping in the assessment of myocardial fibrosis in patients with hypertrophic cardiomyopathy (HCM). Methods:Forty HCM patients and 16 healthy volunteers who underwent CMR examination between December 2021 and May 2022 were prospectively enrolled. T 1ρ mapping, pre-and post-contrast T 1 mapping, and gadolinium contrast-enhanced delayed enhancement (LGE) imaging were performed in HCM patients, while T 1ρ mapping and T 1 mapping were performed in volunteers. HCM patients were further divided into LGE-positive (LGE+) and LGE-negative (LGE-) groups based on the presence or absence of LGE. The T 1ρ and pre-contrast T 1 values of the left ventricular myocardium of HCM patients and volunteers were measured, and the extracellular volume fraction (ECV) of the left ventricular myocardium of HCM patients was measured using pre-and post-contrast T 1 mapping. One-way ANOVA was used to compare the T 1ρ and pre-contrast T 1 values among the LGE+, LGE-, and volunteer groups, and pairwise comparisons were further corrected using the Bonferroni method. Receiver operating characteristic (ROC) analysis was used to evaluate the diagnostic performance of pre-contrast T 1 and T 1ρ values in distinguishing LGE+ and LGE- patients from volunteers. The chi-square test or Fisher′s exact probability test was used for categorical variable comparisons. Pearson correlation coefficient was used to evaluate the correlation between T 1ρ and pre-contrast T 1, and ECV. Results:There were no significant differences in age, gender, and body surface area among the LGE+, LGE-, and healthy control groups ( P>0.05). Compared to the HC group, both the T 1ρ value ( t=5.74, P<0.001) and the pre-contrast T 1 value ( t=3.99, P<0.001) increased in LGE positive group, as well as in the LGE negative group (T 1ρ: t=4.19, P<0.001; T 1: t=2.06, P<0.044). ROC analysis showed that the area under the curve (AUC) of T 1ρ and pre-contrast T 1 in distinguishing LGE+patients from healthy controls were 0.93 (sensitivity 84.0%, specificity 93.8%) and 0.87 (sensitivity 84.0%, specificity 87.5%), respectively. The AUC of T 1ρ and pre-contrast T 1 in distinguishing LGE-patients from healthy controls were 0.84 (sensitivity 86.7%, specificity 68.8%) and 0.68 (sensitivity 60%, specificity 68.8%), respectively. The correlation analysis showed that the T 1ρ value of the left ventricular myocardium was positively correlated with the pre-contrast T 1 value ( r=0.31, P=0.02) and ECV value ( r=0.38, P=0.02). Conclusion:Without the use of contrast agents, T 1ρ mapping shows good performance for myocardial replacement fibrosis and diffuse fibrosis in HCM patients.

Objective:Using the Taqman low-density array (TLDA) to develop a detection method which can rapidly type influenza A virus and the subtypes of H1-H16 and N1-N9, which is suitable for rapid typing and identification of influenza A in influenza like cases and avian influenza samples.Methods:The primers and probes of influenza A, H1-16 subtypes, N1-9 subtypes were designed and pre-customized on the TLDA reaction chip; Optimize the TLDA annealing temperature; The sensitivity of TLDA was evaluated by 10 fold gradient dilution of influenza A virus nucleic acid of various subtypes and the digital PCR; The specificity of the TLDA was verified by influenza B, adenovirus, respiratory syncytial virus and other respiratory viruses. At the same time, a variety of influenza A viruses that have been clearly typed were selected to evaluate the specificity and effectiveness of TLDA; The TLDA was used to detect 16 samples of influenza like cases and 24 samples of external environment of avian influenza.Results:The best annealing temperature of TLDA was 60 ℃, the detection sensitivity of TLDA was between 1.52 and 8.00 copies/μl for H1N1, H3N2, H5N6, H7N9 and H9N2, there was no specific cross reaction with influenza B, avian influenza, adenovirus, respiratory syncytial virus and other respiratory viruses. A total of 12 influenza positive samples and 24 samples from environmental surveillance of avian influenza were detected by TLDA, all of the result of samples were correct in typing.Conclusions:The high-throughput detection method of influenza A virus based on TLDA has good sensitivity and specificity, and the result of clinical samples show that the TLDA is suitable for rapid detection of influenza like cases and avian influenza samples, especially for rapid subtype screening and identification of new influenza A virus that cannot be identified by conventional commercial kits.

Objective:To investigate the clinical and cardiac magnetic resonance (CMR) characteristics of heart involvement in patients with Fabry disease (AFD).Methods:From January 2018 to March 2021, eight AFD patients [3 males and 5 females, mean age (50±11) years old, range 26-60 years old] confirmed by genetic testing or pathology in Fuwai Hospital were retrospectively included in this study. At the same time, sixteen patients with hypertrophic cardiomyopathy (HCM) [6 males and 10 females, mean age (46±15) years old] and 16 healthy individuals [6 males and 10 females, mean age (51±11) years old] were included as controls. The clinical baseline data and CMR data of the patients were collected and analyzed. The CMR data were analyzed using the software CVI42, with the corresponding parameters automatically generated. One-way ANOVA or Kruskal-Wallis test was used to compare the differences in the parameters among the three groups. Independent-samples t test, Fisher precise test or Mann-Whitney U test were used for the comparison between each two groups. Results:Statistically significant difference was found in renal insufficiency between the HCM group and the AFD group; No other significant difference was found in other clinical factors and ECG results (all P>0.05). CMR results showed that in the AFD group, there were 5 cases with symmetric or roughly symmetric hypertrophy, and 3 with asymmetric hypertrophy. The late gadolinium enhancement (LGE) showed myocardial enhancement in 5 patients, mainly presenting as multiple intermural enhancement, and partially as local subendocardial enhancement. In the HCM group, fourteen cases suffered mainly asymmetric ventricular septal thickening, with or without thickening of other parts of left ventricular wall; and 2 cases had thickening of middle and distal part of the left ventricle. The LGE showed myocardial enhancement in 14 patients, which manifested as focal or patchy enhancement in hypertrophic myocardium, including focal enhancement in the right ventricular insertion of ventricular septum (more common) and subendocardial enhancement in the middle and far segments of left ventricle. Statistically significant difference was found in the differences between the left atrial anterior posterior diameter, the maximum wall thickness of left ventricular, the left ventricular myocardial mass index (LVMI) and the native T 1 value among the three groups (all P<0.001). However, there was no statistically significant difference in the left atrial anterior posterior diameter and the maximum wall thickness of left ventricular between AFD group and HCM group ( P>0.05). The LVMI in AFD group was higher than that in healthy group and HCM group (all P<0.05). Significant difference was found in the native T 1 value among the three groups, with the native T 1 value of the AFD group [(1 177.4±46.0) ms] was significantly lower than that of the healthy group [(1 244.5±34.3) ms] and the HCM group [(1 278.8±41.6) ms], with ( F=13.10, P<0.001). Conclusions:The clinical characteristics of AFD and HCM are quite similar. When AFD is suspected, CMR imaging should be the first choice for imaging examination. Especially, T 1 mapping imaging can provide important information for the diagnosis of AFD.

Objective:To explore the clinical value of T 1 mapping/indexed extracellular volume fraction (iECV) quantified with cardiac MR (CMR) parameters, and its correlation with traditional indicators of myocardial dysfunction in aortic insufficiency (AI) patients. Methods:A total of 36 patients clinically and radiologically diagnosed with chronic AI in our hospital between May 2012 and February 2016 were retrospectively selected. All AI patients underwent conventional CMR protocol, native and post T 1 mapping. CMR parameters, such as aortic regurgitant fraction (RF), late gadolinium enhancement (LGE) mass fraction, myocardial extracellular volume fraction (ECV) and iECV. Based on the values of aortic RF, AI patients were divided into mild AI group (9 cases), moderate AI group (14 cases) and severe AI group (13 cases). The clinical characteristics were teased from the patients′ electronic medical records. Univariate analysis of variance was used to compare the measurement data of native T 1 mapping, post-contrast T 1 mapping, ECV, and iECV. LSD test was used for pair wise comparison between the mild AI, moderate AI and severe AI groups. Data about cardiovascular history, New York Heart Association (NYHA) heart function classification, and LGE were compared by chi-square test or Fisher exact test. The correlation between left ventricle ejection fraction (LVEF) and iECV was evaluated by Spearman correlation analysis. Results:There was no difference in age, sex, cardiovascular history among the three groups. Comparison of patients with different severity of AI in the three groups: (1) There was statistically significant difference in the LGE positive rate among the three groups ( P=0.023), while the myocardial replacement of fibrosis increased with the grade of aortic regurgitation. (2) There was no statistically significant difference in the measurement data of native T 1 mapping, post-contrast T 1 mapping, ECV among the three groups ( H=1.815, 0.929, 2.496, all P values>0.05), while the diffuse myocardial fibrosis tended to increase with the degree of aortic regurgitation. There was statistically significant difference in iECV among the three groups ( H=16.725, P<0.001). The measurement data of iECV in the severe AI group was significantly higher than those in the other two groups ( P<0.05). LVEF value was inversely correlated with iECV ( r=-0.649, P<0.001). Conclusions:Quantitative T 1 mapping/iECV can serve as a parameter to noninvasively identify diffuse myocardial fibrosis in AI patients of different severities. It changes with LVEF and can manifest the reversible stage of left ventricular decompensation.