Age-Related Utilization of Thrombus Aspiration in Patients With ST-Segment Elevation Myocardial Infarction: Findings From the Improving Care for Cardiovascular Disease in China Project

Background

There are some controversies on the utilization and benefits of thrombus aspiration in patients with ST-segment elevation myocardial infarction (STEMI). However, a few studies investigated this issue and the age-associated effects among the large population in China. Hence, we aimed to figure out the age-associated utilization and in-hospital outcomes of thrombus aspiration to improve therapeutic decisions in clinical routine.

Methods

We retrospectively recruited 13,655 eligible STEMI patients from the database of the Improving Care for Cardiovascular Disease in China-Acute Coronary Syndrome project. These subjects were allocated into primary percutaneous coronary intervention (PPCI)-only group and thrombus aspiration group after being subdivided into three age groups (G21−50, G51−75, and G76−95). After 1:1 propensity score matching for PPCI-only and thrombus aspiration groups, a total of 8,815 matched patients were enrolled for the subsequent analysis. The primary outcome was in-hospital cardiovascular death, and the key safety outcome was in-hospital stroke.

Results

We observed that the ratio of STEMI patients undergoing thrombus aspiration to PPCI-only reduced with aging. For patients ≤ 75 years, the culprit lesion suffered from thrombus aspiration was mainly located in the left anterior descending branch, and left-ventricular ejection fraction (LVEF) was lower (G21−50: 54.9 ± 8.9 vs. 56.0 ± 8.7%, P = 0.01; G51−75: 53.9 ± 9.6 vs. 54.8 ± 9.0%, P = 0.001) and the rate of regional wall motion abnormality was higher (G21−50: 75.7 vs. 66.5%, P < 0.001; G51−75: 75.4 vs. 69.1%, P < 0.001) in the thrombus aspiration group. By contrast, for patients > 75 years, the right coronary artery was the predominant culprit lesion undergoing thrombus aspiration, LVEF (63.1 ± 10.5 vs. 53.1 ± 9.5%, P = 0.985) and the regional wall motion abnormality (79.2 vs. 74.2%, P = 0.089) were comparable between the two treatment groups. Thrombus aspiration neither reduced the in-hospital risk of cardiovascular death, all-cause death, recurrent myocardial infarction, acute stent thrombosis, heart failure, cardiogenic shock, and sudden cardiac arrest nor increased stroke risk compared with the PPCI-only group. However, after adjustment for age, thrombus aspiration presented the tendency to reduce the incidence of sudden cardiac arrest (4.9 vs. 2.5%, P = 0.06) and in-hospital cardiovascular death at 3 days (hazard ratio 0.46; 95% CI, 0.20–1.06; log-rank P = 0.08) in G76−95 group and tended to increase the incidence of heart failure in G51−75 (5.7 vs. 6.9%, P = 0.07).

Conclusion

The thrombus aspiration neither significantly reduced the in-hospital incidence of major adverse cardiac events nor increased stroke risk. However, it might play a protective role in reducing in-hospital sudden cardiac arrest and increasing survival from cardiovascular death at 3 days for the elderly.

Quantitative Assessment of Left and Right Atrial Strains Using Cardiovascular Magnetic Resonance Based Tissue Tracking

Background: Left and right atrium (LA and RA) exert an essential and dynamic role in ventricular filling and hence affect heart performance. Strain quantification has been reported as a novel parameter to assess function. However, the assessment of bi-atrial strains with cardiovascular magnetic resonance (CMR) based techniques is still limited and gender- and age-specific normal values in a healthy population are missing.

Methods: One hundred and fifty healthy volunteers (49.8 ± 17.3 years, 75 males) undergoing 1.5 Tesla CMR examination were retrospectively and consecutively recruited. LA and RA free wall (RAFW) radial and longitudinal strains (RS and LS) associated with atrial reservoir, conduit and booster pump functions were evaluated with CMR based tissue tracking (CMR-TT) technique.

Results: The reservoir, conduit and pump LS resulted as 30.7 ± 10.2%, 19.5 ± 8.2%, 10.9 ± 3.7% for LA, and 52.2 ± 17.6%, 33.3 ± 14.2%, 19.1 ± 8.5% for RAFW, respectively. The amplitude of RA strains was significantly larger than that of LA strains, except for conduit RS. With the increase of age, the decrement of majority of reservoir and conduit strains were observed, while pump strains remained unaffected. Females presented with significantly larger RAFW strains compared with males, especially in the elderly. In addition to the positive correlation between atrial strains and emptying fraction, the negative correlation between atrial strains and volume index was also confirmed. Intra-observer reproducibility of LA strains was superior to RAFW strains (coefficient of variation: 10.12–17.04% vs. 10.80–27.36%, respectively), and the measurement of reservoir and conduit strains was more reproducible in comparison with pump strain.

Conclusion: CMR-TT is a feasible and reproducible technique to quantify LA and RA strains and determine atrial phasic functions. The existence of age- and gender-related difference of strains suggests the necessity to establish specific normal values for individual populations.

Left ventricular myocardial strain quantification with two- and three-dimensional cardiovascular magnetic resonance based tissue tracking

Background

Cardiovascular magnetic resonance based tissue tracking (CMR-TT) was reported to provide detailed insight into left ventricular (LV) contractile function and deformation with both of two- and three-dimensional (2/3D) algorithms. This study was designed to investigate the feasibility and reproducibility of these two techniques for measuring LV global and segmental strain, and establish gender- and age-related reference values of global multi-dimensional peak strains among large healthy population.

Methods

We retrospectively recruited 150 healthy volunteers (75 males/females) and divided them into three age groups (G_20-40, G_41-60 and G_61-80). LV global mean and peak strains as well as segmental strains in radial, circumferential and longitudinal directions were derived from post-hoc 2/3D CMR-TT analysis of standard steady-state free precession (SSFP) cine images acquired at 1.5T field strength.

Results

Both 2D and 3D CMR-TT modalities enable the tracking of LV myocardial tissues and generate global and segmental strain data. By comparison, 3D CMR-TT was more feasible in measuring segmental deformation since it could generate values at all segments. The amplitudes of LV 3D global peak strain were the smallest among those of 2/3D corresponding global mean or peak strains except in the radial direction, and was highly correlated with 2D global mean strains (correlation coefficient r=0.71-0.90), 2D global peak strains (r=0.75-0.89) and 3D global mean strains (all r=0.99). In healthy cohort, LV 3D global peak values were 44.4%±13.0% for radial, -17.0%±2.7% for circumferential and -15.4%±2.3% for longitudinal strain. Females showed significantly larger amplitude of strains than males, especially in G_61-80 (P<0.05). The subjects in G_61-80 showed larger amplitude of strains than the volunteers in younger groups. The intra- and inter-observer agreement of 2/3D CMR-TT analysis in evaluating LV myocardial global deformation was better than segmental measurement.

Conclusions

CMR-TT is a feasible and reproducible technique for assessing LV myocardial deformation, especially at the global level. The establishment of specific reference values of LV global and segmental systolic strains and the investigation of dimension-, gender- and age-related differences provide a fundamental insight into the features of LV contraction and works as an essential step in clinical routine.

Right ventricular free wall longitudinal strain and strain rate quantification with cardiovascular magnetic resonance based tissue tracking

Cardiovascular magnetic resonance based tissue tracking (CMR-TT) was reported to provide detailed insight into left ventricular mechanical features. However, inadequate knowledge of the right ventricle (RV) mechanical deformation has been acquired by this advanced technique so far. It was the aim of this study to establish reference values of RV free wall (RVFW) global, regional and segmental longitudinal peak strain and strain rate (LS and LSR), and to investigate the gender- and age-related difference as well as the base-to-apex gradient of RVFW-LS and LSR with CMR-TT. 150 healthy volunteers (75 males/females) were retrospectively and continuously recruited and subdivided into three age groups (G_20–40, G_41–60 and G_61–80). RVFW global, regional (basal, middle-cavity and apical) and segmental LS (GLS, RLS, SLS) along with systolic and diastolic LSR were generated by post-hoc CMR-TT analysis of standard steady-state free precession long-axis four-chamber view cine images acquired at 1.5T field strength. The reference value of myocardial RVFW-GLS was − 24.9 ± 5.2%. We found that females showed more negative GLS than males except in the youngest group, and no age-related difference of GLS was observed in both gender groups. RLS and SLS presented with the same age-related tendency as GLS. The basal and middle-cavity LS were similar between each other and significantly larger than apical LS. RVFW-GLSR resulted as − 1.73 ± 0.58 s⁻¹ and 1.69 ± 0.65 s⁻¹ during systolic and diastolic phases, respectively. The diastolic GLSR of males tended to decline with the ageing and was significantly lower than that of females in G_61–80 group. Regional and segmental LSR showed significant gender-related differences in certain basal and apical region/segments without any age-related effects. CMR-TT overcomes the difficulty in measuring RV global and segmental deformation. The establishment of the vendor-, gender- and segment-specific reference values of RVFW-LS and LSR is essential for the rapid and efficient utilization of CMR-TT modality in the clinical routine.

Triglyceride to high-density lipoprotein cholesterol ratio as a risk factor of repeat revascularization among patients with acute coronary syndrome after first-time percutaneous coronary intervention

Background

It is clinically important to identify high-risk patients with acute coronary syndrome (ACS) who may require repeat revascularization. This retrospective study identified risk factors for repeat revascularization among ACS patients after first-time successful percutaneous coronary interventions (PCIs). The predictive value of the triglyceride to high-density lipoprotein cholesterol (TG/HDL-C) ratio for repeat revascularization was also evaluated.

Methods

We enrolled consecutive ACS patients who had coronary angiography performed during the period from 6 to 12 months after a first-time successful PCI. The primary outcome of the study was to identify the risk factors of repeat revascularization. The subjects were stratified based on repeat PCI events. After comparing various clinical characteristics, univariate and multivariate Cox proportional hazard model analyses were adopted to evaluate the effects of risk factors on repeat revascularization.

Results

The patients (n=271) were divided into the event (+) group (n=101) and the event (-) group (n=170). In the event (+) group, target lesion revascularization (TLR) accounted for 20.79% and target vessel revascularization (TVR) accounted for 50.49% of the patients. In contrast, 52.47% of the patients required de novo vessel revascularization (DVR). After adjustment for confounding factors, the TG/HDL-C ratio [hazard ratio (HR) =1.206, 95% confidence interval (CI): 1.016-1.431, P=0.032 for each higher TG/HDL-C ratio unit] and the Gensini score (HR =1.012, 95% CI: 1.005-1.018, P<0.001 for each higher Gensini score unit) were independent risk factors for a repeat PCI. Subgroup analyses showed that higher TG/HDL-C ratios were associated with a significantly higher risk of repeat PCIs in the male, hypertensive, and diabetes mellitus subgroups.

Conclusions

The TG/HDL-C ratio and Gensini score could serve as risk factors for repeat revascularization in ACS patients after a first-time successful PCI.

[Influences of follow-up methods on rehabilitation and compliance of patients with severe scar after burns]

Objective: To observe the influences of different follow-up methods on rehabilitation and compliance of patients with severe scar after burns. Methods: From January 2012 to May 2016, medical records of 116 patients with severe scar after burns who were admitted to our unit, discharged after wound healing and conforming to the criteria, were retrospectively analyzed. They were divided into face-to-face follow-up group [n=59, 45 males and 14 females, aged (36±9) years] and routine follow-up group [n=57, 44 males and 13 females, aged (35±9) years] based on different follow-up methods they received. On the day of discharge and in post discharge month (PDM) 1, 3, and 6, the Vancouver Scar Scale (VSS) was used to evaluate the hypertrophic scar in joints, Activities of Daily Living (ADL) scale was used to evaluate the disability of patients in the 2 groups. In PDM 1, 3, and 6, Medical Compliance Behavior Questionnaire was used to investigate the medical compliance behaviors of patients in the 2 groups. Data were processed with chi-square test, t test with Bonferroni correction, and analysis of variance for repeated measurement. Results: (1) The VSS score of patients in face-to-face follow-up group on the day of discharge was (11.1±0.7) points, which was close to (11.7±0.7) points of routine follow-up group (t=2.021, P>0.05). The VSS scores of patients in face-to-face follow-up group in PDM 1, 3, and 6 were (10.5±0.6), (8.6±0.7), and (4.7±0.5) points, which were significantly lower than (11.4±0.7), (10.9±1.0), and (9.4±0.8) points of routine follow-up group respectively (t=2.034, 2.033, 2.042, P<0.05 or P<0.01). (2) The ADL score of patients in face-to-face follow-up group on the day of discharge was close to that of routine follow-up group (t=1.781, P>0.05). The ADL scores of patients in face-to-face follow-up group in PDM 1, 3, and 6 were higher than those of routine follow-up group respectively (t=9.683, 8.584, 9.772, P<0.01). (3) The compliance rates of consisted rehabilitation, reasonable diet, and timing consultation of patients in face-to-face follow-up group were better than those of routine follow-up group respectively (χ(2)=19.015, 13.251, 8.652, P<0.01). Conclusions: Compared with routine follow-up by phone, face-to-face follow-up can do better in evaluating the scar condition and ADL of patients with severe scar after burns, and improve the medical compliance rates of patients, which is worthy of clinical promotion.

[The clinical significance of CD(4)(+)CD(69)(+) T lymphocytes in patients with autoimmune hemolytic anemia/Evans syndrome]

Objective: To investigate the significant of peripheral CD(4)(+) CD(69)(+) T lymphocytes in patients with autoimmune hemolytic anemia (AIHA)/Evans syndrome (ES). Methods: In this study peripheral blood samples from 32 patients with AIHA/ES (15 hemolytic episode patients, 17 remission patients) and 13 healthy controls were collected. Patients with AIHA/ES were recruited in Tianjin Medical University General Hospital from October 2015 to May 2016. The percentages of CD(69)(+) T lymphocytes were analyzed by flow cytometry. The expression of CD(69) mRNA in CD(4)(+) T lymphocytes which was sorted from peripheral blood by magnetic activated cell sorting (MACS) was detected using real-time PCR. Soluable CD(69) was measured by ELISA. Results: In hemolytic episode patients, the ratio of CD(3)(+)CD(69)(+)/CD(3)(+)T lymphocytes [(3.08±1.48)%] was significantly higher than that in healthy controls [(1.28±0.83)%, P<0.01] and in remission group[(1.96±1.33)%, P<0.05]. The absolute count of CD(3)(+)CD(69)(+)T lymphocytes in hemolytic episode group [(2.94±1.81)×10(7)/L] was higher than that in healthy controls [(1.48±1.42)×10(7)/L, P<0.05]. The ratio of CD(3)(+)CD(4)(+)CD(69)(+)/CD(3)(+)CD(4)(+)T cells in hemolytic episode group [(2.16±1.56)%] was significantly higher than that in remission group [(1.16±0.62)%, P<0.05] and healthy controls[(0.94±0.78)%, P<0.05]. The quantity of CD(3)(+)CD(4)(+)CD(69)(+)T lymphocytes in hemolytic episode group[(1.04±0.98)×10(7)/L] was higher than in healthy controls [(0.44±0.38)×10(7)/L, P<0.05]. The ratio of CD(3)(+)CD(8)(+)CD(69)(+)/CD(3)(+)CD(8)(+)T lymphocyte in hemolytic episode group [(4.87±2.56)%] was significantly higher than that in healthy controls[(1.83±1.27)%, P<0.01]. The quantity of CD(3)(+)CD(8)(+)CD(69)(+)T lymphocytes in three groups did not show significant difference. The ratio of CD(3)(+)CD(4)(+)CD(69)(+)/CD(3)(+)CD(4)(+) T lymphocytes in hemolytic episode group was negatively correlated with hemoglobin (Hb) (P<0.01) , positively correlated with the percentage of reticulocytes (Ret%) (P=0.01) total bilirubin(TBil), indirect bilirubin(IBil) (P<0.01) and not correlated with absolute reticulocytes count, lactic dehydrogenase (LDH), complement 3(C3), complement 4 (C4). The ratio of CD(3)(+)CD(4)(+)CD(69)(+)/CD(3)(+)CD(4)(+)T lymphocytes in remission group was negatively correlated with Hb (P<0.05). In hemolytic episode patients CD(69) mRNA (32.26±35.11) was significantly higher than that in remission group(6.05±5.87) (P<0.05) and healthy controls (1.76±1.85)(P<0.01). CD(69) mRNA in remission group was significantly higher than healthy controls (P<0.05). Serum CD(69) in hemolytic episode patients [(494.21±16.06) ng/L] was significantly higher than that in healthy controls [(441.39±104.6) ng/L, P<0.05]. Conclusion: Our findings suggest that the proportion of CD(4)(+)CD(69)(+) T lymphocytes increase in AIHA/ES patients, which is correlated with the severity of disease.

Myocardial strain characteristics and outcomes after transcatheter aortic valve replacement

BACKGROUND

Objective of this study was to make an assessment of standard functional and defor-mation parameters (strain) in patients after transcatheter aortic valve replacement (TAVR) by cardiac magnetic resonance imaging (CMR) and the evaluation of their prognostic impact.

METHODS

Patients undergoing TAVR received CMR on a 1.5 T whole-body scanner at 3 months after the procedure. Deformation parameters (strain, strain rate, velocity, displacement) were assessed in lon-gitudinal, circumferential and radial orientation using a feature tracking approach. Primary outcome measure was defined according to Valve Academic Research Consortium-2 (VARC-2) criteria.

RESULTS

Eighty-three patients formed the study population. Deformation parameters were significantly reduced in all three orientations for strain (longitudinal: -12.1 ± 5.4% vs. -15.9 ± 1.96%, p < 0.0001; radial: 34.4 ± 15.3% vs. 47.2 ± 11.4%, p < 0.0001; circumferential: -16.8 ± 4.3% vs. -21.1 ± 2.5%, p < 0.0001) and strain rate (longitudinal: -0.79 ± 0.33%/s vs. -0.91 ± 0.23%/s, p = 0.043; radial: 2.5 ± 1.2%/s vs. 2.9 ± 0.9%, p = 0.067; circumferential: -1.1 ± 0.6%/s vs. -1.3 ± 0.3%/s, p = 0.006) in comparison to a healthy control population. Median follow-up was 614 days. During this period, 13 endpoints occurred (cumulative event rate of 10.7%). Patients with event by trend exhibited poorer strain and strain rate in longitudinal and radial orientation without reaching statistical significance (longitudinal strain: -11.2 ± 5.4% vs. -12.3 ± 5.4%, p = 0.52; longitudinal strain rate: -0.73 ± ± 0.23%/s vs. 0.80 ± 0.35%/s, p = 0.53; radial strain: 29.5 ± 19.6% vs. 35.2 ± 14.5%, p = 0.24; radial strain rate: 2.2 ± 1.6%/s vs. 2.6 ± 1.2%/s, p = 0.31).

CONCLUSIONS

Assessment of left ventricular deformation parameters by CMR revealed functional abnormalities in comparison to healthy controls. Prognostic significance remains to be further investi-gated.

Association of genetic variations in miR-146a rs2910164 and miR-149 rs11614913 with the development of classic Kaposi sarcoma

Classic Kaposi sarcoma is a type of vascular proliferative inflammatory disease. Previous studies have reported significant associations between microRNAs expression and the development of classic Kaposi sarcoma. Here, we conducted a case-control study to investigate the association between miR-146a and miR-149 genetic polymorphisms and risk of classic Kaposi sarcoma in a Chinese population. Both classic Kaposi sarcoma patients and healthy controls were recruited between December 2013 and October 2015. Genotyping of miR-146a and miR-149 was performed by polymerase chain reaction-coupled with restriction fragment length polymorphism. Results showed that the GG genotype of miR-146a was associated with increased risk to classic Kaposi sarcoma (OR = 6.00, 95%CI = 1.19-30.12), as compared with the CC genotype. In the recessive model, we found that the GG genotype carried a 4.55-fold increased risk to classic Kaposi sarcoma as compared with the CC + CG genotype (OR = 2.06, 95%CI = 1.04-20.29). In conclusion, our study demonstrated that miR-146a, but not miR-149 polymorphism, is associated with risk to classic Kaposi sarcoma in the Chinese population.

[Oxidative stress and calcium/calmodulin-dependent protein kinase II contribute to the development of sustained β adrenergic receptor-stimulated cardiac hypertrophy in rats]

Sustained activation of β adrenergic receptor (βAR) leads to pathologic cardiac hypertrophy. However, the related mechanisms still remain unclear. In this study, we observe how N-acetylcysteine (NAC) affects the oxidative stress and calcium/calmodulin-dependent protein kinase II (CaMKII) expression in heart of isoproterenol (ISO)-stimulated rats, and investigate whether oxidative stress and CaMKII contribute to the development of sustained βAR-stimulated cardiac hypertrophy. Healthy male Wistar rats were randomly separated into 4 groups: control (CTRL), ISO-treated (ISO), control with NAC supplement (CTRL+NAC) and ISO-treated with NAC supplement (ISO+NAC) groups (6 rats in each group). Systolic blood pressure (SBP) was measured in awake rats with the tail-cuff method every week for two weeks. Heart weight/body weight ratio (HW/BW) and HE staining were used for the detection of myocardial hypertrophy. Myocardial mitochondrial reactive oxygen species (ROS) levels were measured by DCF fluorometry. The expressions of activated-CaMKII (p-CaMKII/CaMKII) and NADPH oxidase 4 (NOX(4)) were determined by Western blot analysis. The results showed that ISO-treated (i.p., daily 3 mg/kg, 2 weeks) rats developed an obvious cardiac hypertrophy as expressed by increases of HW/BW and myocyte cross-section area. Cardiac mitochondrial ROS level was significantly enhanced in ISO group as compared to CTRL group (P < 0.05). The expressions of NOX(4) and p-CaMKII in ISO group were also up-regulated as compared to CTRL group (1.4 and 1.6 times of CTRL, respectively, P < 0.05). NAC supplement significantly suppressed the hypertrophic development of heart in ISO-stimulated rats. The cardiac mitochondrial ROS level showed a significant decrease in rats of ISO+NAC group (P < 0.05 vs ISO). In accordance with this, ISO+NAC group rats also showed marked reductions in the expressions of NOX(4) and p-CaMKII/CaMKII compared to ISO group rats (P < 0.05). There were no significant differences of the detected indices between the rats from CTRL+NAC and CTRL groups. SBP showed no differences among four groups. These results suggest that both oxidative stress and CaMKII play important roles in sustained βAR-stimulated cardiac hypertrophy. NAC may suppress ISO-induced cardiac hypertrophy by down-regulating the expression of activated-CaMKII, and by reducing the level of oxidative stress originated from mitochondria and NADPH oxidase pathways.

Stromal-epithelial interactions modulate the effect of ovarian steroids on goat uterine epithelial cell interleukin-18 release

A primary role of epithelial-stromal interactions in mediating steroid hormone action in the uterus has been established. The present study was undertaken to determine the mode of ovarian steroid action in regulating IL-18 release by goat endometrial epithelial cells (EECs) in the presence and absence of endometrial stromal cells (ESCs). Primary and telomerase-immortalized goat EECs grown alone or cocultured with ESCs were treated with two ovarian steroids, 17β-estradiol (E(2)) and progesterone (P(4)). The IL-18 mRNA and protein expression in EECs were studied by reverse transcript (RT) PCR, ELISA, and Western blot assay. The E(2) and/or P(4) treatment of EECs led to a significant increase in both IL-18 mRNA and protein expression either in the primary or in the immortalized EECs compared with that in EECs without the steroid treatment. However, in the presence of ESCs, IL-18 expression by EECs treated with steroids was significantly decreased compared with cells untreated with E(2) and/or P(4). In addition, significantly high abundance of IL-18 mRNA and protein expression by primary and telomerase-immortalized goat EECs was observed in the presence of ESCs compared with those cells without ESCs. These findings suggest that steroids are important for the control of IL-18 expression in goat EECs. Underlying ESCs are needed to mediate the inhibitory effects of steroids on the IL-18 secretory activity of goat EECs in vitro. The IL-18 abundance expressed by goat EECs in vitro are enhanced by underlying ESCs without the treatment of E(2) and/or P(4).

Molecular mapping of stripe rust resistance gene YrCH42 in Chinese wheat cultivar Chuanmai 42 and its allelism with Yr24 and Yr26

Stripe rust, caused by Puccinia striiformis f. sp. tritici (PST), is one of the most devastating diseases in common wheat (Triticum aestivum L.) worldwide. The objectives of this study were to map a stripe rust resistance gene in Chinese wheat cultivar Chuanmai 42 using molecular markers and to investigate its allelism with Yr24 and Yr26. A total of 787 F2 plants and 186 F3 lines derived from a cross between resistant cultivar Chuanmai 42 and susceptible line Taichung 29 were used for resistance gene tagging. Also 197 F2 plants from the cross Chuanmai 42xYr24/3*Avocet S and 726 F2 plants from Chuanmai 42xYr26/3*Avocet S were employed for allelic test of the resistance genes. In all, 819 pairs of wheat SSR primers were used to test the two parents, as well as resistant and susceptible bulks. Subsequently, nine polymorphic markers were employed for genotyping the F2 and F3 populations. Results indicated that the stripe rust resistance in Chuanmai 42 was conferred by a single dominant gene, temporarily designated YrCH42, located close to the centromere of chromosome 1B and flanked by nine SSR markers Xwmc626, Xgwm273, Xgwm11, Xgwm18, Xbarc137, Xbarc187, Xgwm498, Xbarc240 and Xwmc216. The resistance gene was closely linked to Xgwm498 and Xbarc187 with genetic distances of 1.6 and 2.3 cM, respectively. The seedling tests with 26 PST isolates and allelic tests indicated that YrCH42, Yr24 and Yr26 are likely to be the same gene.