Myocardial infarction with non-obstructive coronary arteries: A comprehensive review and future research directions

Acute coronary syndromes constitute a variety of myocardial injury presentations that include a subset of patients presenting with myocardial infarction with non-obstructive coronary arteries(MINOCA).This acute coronary syndrome differs from type 1 myocardial infarction(MI)regarding patient characteristics,presentation,physiopathology,management,treatment,and prognosis.Two-thirds of MINOCA subjects present ST-segment elevation;MINOCA patients are younger,are more often female and tend to have fewer cardiovascular risk factors.Moreover,MINOCA is a working diagnosis,and defining the aetiologic mechanism is relevant because it affects patient care and prognosis.In the absence of relevant coronary artery disease,myocardial ischaemia might be triggered by an acute event in epicardial coronary arteries,coronary microcirculation,or both.Epicardial causes of MINOCA include coronary plaque disruption,coronary dissection,and coronary spasm.Microvascular MINOCA mechanisms involve microvascular coronary spasm,takotsubo syndrome(TTS),myocarditis,and coronary thromboembolism.Coronary angiography with non-significant coronary stenosis and left ventriculography are first-line tests in the differential study of MINOCA patients.The diagnostic arsenal includes invasive and non-invasive techniques.Medical history and echocardiography can help indicate vasospasm or thrombosis,if one finite coronary territory is affected,or specify TTS if apical ballooning is present.Intravascular ultrasound,optical coherence tomography,and provocative testing are encouraged.Cardiac magnetic resonance is a cornerstone in myocarditis diagnosis.MINOCA is not a benign diagnosis,and its polymorphic forms differ in prognosis.MINOCA care varies across centres,and future multi-centre clinical trials with standardized criteria may have a positive impact on defining optimal cardiovascular care for MINOCA patients.

Preliminary study of letrozole use for improving spermatogenesis in non-obstructive azoospermia patients with normal serum FSH

We investigated whether letrozole （2.5 mg day-1） improves sperm count in non-obstructive azoospermia （NOA） patients. Four men were included in this study, and they had folliculo-stimulating hormone and other hormone levels within the normal range and no varicoceles or chromosomal aberrations. These four patients were administered letrozole for 3 months. Sperm count, testicular volume, gonadotropin, testosterone （T） and estradiol （E2） blood levels were assessed before, during and 1 week after the suspension of treatment. All patients showed spermatozoa in their ejaculate, increased gonadotropin and T levels and lower E2 levels （P〈0.05 in all cases）, when letrozole was administered. This suggests that letrozole treatment might improve sperm count in an NOA sub-population; however, more studies, including the proper controls, are needed to confirm its efficacy.

Outcome of repeated micro-surgical testicular sperm extraction in patients with non-obstructive azoospermia

Aim： To evaluate the outcome of repetitive micro-surgical testicular sperm extraction （mTESE） attempts in non-obstructive azoospermia （NOA） cases, in relation to patients＇ initial testicular histology results. Methods： A total of 68 patients with NOA in whom mTESE had been performed in previous intracytoplasmic sperm injection （ICSI） attempts were reviewed. Results： Among the 68 patients with NOA, the first mTESE yielded mature sperm for ICSI in 44 （64%） （Sp^＋）, and failed in the remaining 24 （36%） （Sp^-）. Following their first trial, 24 patients decided to undergo a second mTESE. Of these 24 patients, no spermatozoa were obtained in 5 patients, and Sp^＋ but no fertilization/pregnancy were achieved in 19. In these 24 cases, mTESE was successively repeated for two （n = 24）, three （n = 4） and four （n = 1） times. The second attempt yielded mature sperm in 3/5 patients from the Sp group and 16/19 patients from the Sp^＋ group. At the third and fourth trials, 4/4 and 1/1 of the original Sp^＋ patients were Sp^＋ again, respectively. Distribution of main testicular histology included Sertoli cell-only syndrome （16%）, maturation arrest （22%）, hypospermatogenesis （21%） and focal spermatogenesis （41%）. Overall, in repetitive mTESE, 24/29 （82%） of the attempts were finally Sp^＋. Conclusion： Repeated mTESE in patients with NOA is a feasible option, yielding considerably high sperm recovery rate. In patients with NOA, mTESE may safely be repeated one or more times to increase sperm retrieval rate, as well as to increase the chance of retrieving fresh spermatozoa to enable ICSI.

The number of spermatozoa collected with testicular sperm extraction is a novel predictor of intracytoplasmic sperm injection outcome in non-obstructive azoospermic patients

The purpose of this study was to determine the relationships between monitors of spermatogenesis and predictors of the intracytoplasmic sperm injection （ICSI） outcome in patients with non-obstructive azoospermia （NOA） undergoing testicular sperm extraction （TESE）. Seventy-nine patients with NOA （mean age： 43.6±5.2 years）, each of whom yielded （97 000±3040） spermatozoa with conventional TESE, were considered in our analysis. Their partners （mean age： 35.8±5.1 years） underwent a total of 184 ICSI cycles; 632 oocytes were collected, 221 oocytes were injected, 141 oocytes were fertilized, 121 embryos were obtained, 110 embryos were transferred, 14 clinical pregnancies were achieved and only one miscarriage occurred. Multivariate regression analysis indicated relationships between the percentage of fertilized oocytes, transferred embryos and clinical pregnancies with the following variable values： female partner＇s age, number of spermatozoa collected, testicular volume, male partner＇s levels of follicle stimulating hormone （FSH）, number of oocytes collected, number of oocytes injected and number of ICSI cycles. A significant inverse relationship was found between female partner＇s age or male partner＇s FSH levels and biochemical pregnancies. A significant direct relationship emerged between the number of ICS! cycles and the percentage of oocytes fertilized, embryos transferred and biochemical pregnancies, and between the number of spermatozoa collected per testicular biopsy and biochemical pregnancies. The number of spermatozoa was positively linked to the number of clinical pregnancies, independent of the number of ICSI cycles and the number of oocytes collected/injected. The number of spermatozoa collected, FSH level and testicular volume are monitors of spermatogenesis linked to ICSI success.

A susceptibility locus rs7099208 is associated with non-obstructive azoospermia via reduction in the expression of FAM160B1

Non-obstructive azoospermia （NOA） is a severe defect in male reproductive health that occurs in 1% of adult men. In a previous study, we identified that rs7099208 is located within the last intron of FAM160B1 at 10q25.3. In this study, we analysed expression Quantitative Trait Loci （eQTL） of FAM16OB1, ABLIM1 and TRUB1, the three genes surrounding rs7099208. Only the expression level of FAM16OB1 was reduced for the homozygous alternate genotype （GG） of rs7099208, but not for the homozygous reference or heterozygous geno- types. FAM160B1 is predominantly expressed in human testes, where it is found in spermatocytes and round sper- matids. From 17 patients with NOA and five with obstructive azoospermia （OA）, immunohistochemistry revealed that expression of FAM160B1 is reduced, or undetectable in NOA patients, but not in OA cases or normal men. We conclude that rs7099208 is associated with NOA via a reduction in the expression of FAM160B1.

Clinical outcomes of sacral neuromodulation in non-neurogenic,non-obstructive dysuria:A 5-year retrospective,multicentre study in China

BACKGROUND Management of non-neurogenic,non-obstructive dysuria represents one of the most challenging dilemmas in urological practice.The main clinical symptom is the increase in residual urine.Voiding dysfunction is the main cause of dysuria or urinary retention,mainly due to the decrease in bladder contraction(the decrease in contraction amplitude or duration)or the increase in outflow tract resistance.Sacral neuromodulation(SNM)has been used for>10 years to treat many kinds of lower urinary tract dysfunction.It has become increasingly popular in China in recent years.Consequently,studies focusing on nonneurogenic,non-obstructive dysuria patients treated by SNM are highly desirable.AIM To assess the outcome of two-stage SNM in non-neurogenic,non-obstructive dysuria.METHODS Clinical data of 54 patients(26 men,28 women)with non-neurogenic,nonobstructive dysuria treated by SNM from January 2012 to December 2016 in ten medical centers in China were retrospectively analyzed.All patients received two or more conservative treatments.The voiding diary,urgency score,and quality of life score before operation,after implantation of tined lead in stage I(test period),and during short-term follow-up(latest follow-up)after implantation of the implanted pulse generator in stage II were compared to observe symptom improvements.RESULTS Among the 54 study patients,eight refused to implant an implanted pulse generator because of the unsatisfactory effect,and 46 chose to embed the implanted pulse generator at the end of stage I.The conversion rate of stage I to stage II was 85.2%.The average follow-up time was 18.6 mo.There were significant differences between baseline(before stage I)and the test period(after stage I)in residual urine,voiding frequency,average voiding amount,maximum voiding amount,nocturia,urgency score,and quality of life score.The residual urine and urgency score between the test period and the latest follow-up time(after stage II)were also significantly different.No significant differences were observed for other parameters.No wound infection,electrode breakage,or other irreversible adverse events occurred.CONCLUSION SNM is effective for patients with non-neurogenic,non-obstructive dysuria showing a poor response to traditional treatment.The duration of continuous stimulation may be positively correlated with the improvement of residual urine.

Non-obstructive coronary artery disease and cardiovascular events in patients with angina-like chest pain detected by coronary angiography:a Chinese cohort study

Objective The utility of non-obstructive coronary artery diseases(NOCAD) in cardiovascular events (CVE) among Chinese patients has less been evaluated. Our objective was to investigate the prognostic value of NOCAD in patients with angina-like chest pain detected by coronary angiography (CAG) in a large Chinese cohort study.

Testicular fine needle aspiration for sperm retrieval in non-obstructive azoospermia

Objective: To investigate the feasibility of obtaining mature spermatozoa for intracytoplasmic sperm injection (ICSI) by testicular fine needle aspiration (TEFNA) in men diagnosed non-obstructive azoospermia. Methods: TEFNA was performed in 121 patients with a mean of 15 punctures and aspirations from each testis with a #23 butterfly needle connected to a 20 mL syringe with an aspiration handle. Results: One hundred and twenty-one patients underwent 176 TEFNA cycles. Testicular sperm were recovered in 56.3 % (99/176) cycles from 57 % (69/121) of patients. The sperm recovery rate was 46.7 % (21/45) in patients with Sertoli cell-only syndrome, 45.7 % (16/35) in patients with maturation arrest, 96.1 % (25/26) in patients with hypospermatogenesis and 63.6 % (7/11) in patients of non-mosaic Klinefelter's syndrome as judged by testicular histology. No sperm were found in 3 cases with post-irradiation fibrosis and one, after resection and chemotherapy of unilateral testicular cancer. In 87 cycles of ICSI using the husbands' sperm, 591 mature oocytes were injected, 218 (36.9 %) were normally fertilized and 202 embryos developed; 178 were transferred in 62 cycles resulting in 26 pregnancies (41.9 %) with 44 gestational sacs (implantation rate: 24.7 %). Conclusion: TEFNA was an efficient, easy to learn, safe and well tolerated treatment in patients with non-obstructive azoospermia.

Combined evaluation of inhibin B, follicle stimulating hormone and luteinizing hormone improve sperm retrieval prediction in patients with non-obstructive azoospermia

Introduction: Non-invasive methods that can predict sperm recovery in patients with non-obstructive azoospermia (NOA) arouse interest of clinicians. The aim of this study was to evaluate the predictive value of sperm retrieval in NOA. Materials and Methods: In the retrospective study, fine needle aspiration (FNA) was performed on 306 patients with NOA at the department of andrology, Wuhan Tongji Reproductive Medical Hospital. Inhibin B, FSH and LH plasma levels were analyzed and sperms were retrieved in 67 of 306 cases (21.89%). Results: There were statistically significant differences between successful and unsuccessful sperm recoverygroups in terms of mean serum inhibin B, FSH and LH levels. The areas under the curve (AUC) of inhibin B, FSH and LH were 0.696, 0.729 and 0.747 respectively, and the AUC for the combined value of the three hormones is 0.832. The cut-off points were 27.31 pg/ml, 11.68 IU/L and 4.04 IU/L for inhibin B, FSH and LH respectively. Conclusions: This study suggests that the combined evaluation of inhibin B, FSH and LH is a more effective predictor for successful sperm retrieval in patients with NOA before decision making of an invasive procedure than any single factor.

Research progress of real-time sonoelastography to evaluate testicular spermatogenic function in non-obstructive azoospermia

Objective: The azoospermia is increasingly becoming prevalent year by year,which has been plaguing a great number of infertile couples. Testes biopsy is a gold index to evaluate the testicular spermatogenesis in patients with anspermia. However, it is more invasive and may not accurately reflect the whole spermatogenic function of the testes. In recent years, with the continuous development of ultrasound and assisted reproductive technology, real-time sonoelastography has been widely applied in the evaluation of spermatogenic function in patients with azoospermia. It is still at the initial stage, but shows good application prospects. In this paper, we will summarize and review the present status of male infertility and the clinical application and research progress of real-time sonoelastography in the evaluation of the testicular spermatogenic function of non-obstructive azoospermia patients.

Application and optimization design of non-obstructive particle damping-phononic crystal vibration isolator in viaduct structure-borne noise reduction

The problems associated with vibrations of viaducts and low-frequency structural noise radiation caused by train excitation continue to increase in importance.A new floating-slab track vibration isolator-non-obstructive particle damping-phononic crystal vibration isolator is proposed herein,which uses the particle damping vibration absorption technology and bandgap vibration control theory.The vibration reduction performance of the NOPD-PCVI was analyzed from the perspective of vibration control.The paper explores the structure-borne noise reduction performance of the NOPD-PCVIs installed on different bridge structures under varying service conditions encountered in practical engineering applications.The load transferred to the bridge is obtained from a coupled train-FST-bridge analytical model considering the different structural parameters of bridges.The vibration responses are obtained using the finite element method,while the structural noise radiation is simulated using the frequency-domain boundary element method.Using the particle swarm optimization algorithm,the parameters of the NOPD-PCVI are optimized so that its frequency bandgap matches the dominant bridge structural noise frequency range.The noise reduction performance of the NOPD-PCVIs is compared to the steel-spring isolation under different service conditions.

Non-obstructive Coronary Artery Disease in Chinese Patients with Angina Diagnosed by Coronary Angiography:A Retrospective Study

Objective:This study aimed to estimate the proportion of non-obstructive coronary artery disease(CAD)patients in large percutaneous coronary intervention(PCI)centers in China.Methods:The study was conducted at 6 large PCI centers in China from January 1,2013 to December 31,2015.Demographic and clinical data were collected from medical records,prescription records,and laboratory reports of patients with symptoms of angina who underwent coronary angiography(CAG).Results:A total of 1713 patients were consecutively screened,1600 of whom were included in the study.CAG showed that 300 patients had non-obstructive CAD while 1300 had obstructive CAD.Among the 300 patients with non-obstructive CAD,203 displayed mild coronary stenosis(20%-49%)and 91 had normal coronary status(ie,<20%stenosis).Of the 1300 patients with obstructive CAD,61.6%(801/1300)had typical symptoms of angina,compared with 49.3%(148/300)for patients with nonobstructive CAD.In addition,there were more women than men in the non-obstructive CAD group,whereas the reverse was observed among obstructive CAD patients.Conclusion:The prevalence of non-obstructive CAD in the Chinese population with coronary heart disease was estimated to be approximately 20%.Additionally,typical angina symptoms were correlated with obstructive CAD,whereas female gender was identified as a risk factor for non-obstructive CAD.

RNAs in the testicular tissue of patients with non-obstructive azoospermia

Circular RNAs(circRNAs)are highly conserved and ubiquitously expressed noncoding RNAs that participate in multiple reproductionrelated diseases.However,the expression pattern and potential functions of circRNAs in the testes of patients with non-obstructive azoospermia(NOA)remain elusive.In this study,according to a circRNA array,a total of 37881 circRNAs were identified that were differentially expressed in the testes of NOA patients compared with normal controls,including 19874 upregulated circRNAs and 18007 downregulated circRNAs.Using quantitative real-time polymerase chain reaction(qRT-PCR)analysis,we confirmed that the change tendency of some specific circRNAs,including hsa_circ_0137890,hsa_circ_0136298,and hsa_circ_0007273,was consistent with the microarray data in another larger sample.The structures and characteristics of these circRNAs were confirmed by Sanger sequencing,and fluorescence in situ hybridization revealed that these circRNAs were primarily expressed in the cytoplasm.Bioinformatics analysis was used to construct the competing endogenous RNA(ceRNA)network,and numerous miRNAs that could be paired with circRNAs validated in this study were reported to be vital for spermatogenesis regulation.Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses indicated that genes involved in axoneme assembly,microtubule-based processes,and cell proliferation were significantly enriched.Our data suggest that there are aberrantly expressed circRNA profiles in patients with NOA and that these circRNAs may help identify key diagnostic and therapeutic molecular biomarkers forNoA patients.

Laboratory and Clinical Outcomes of Single Sperm Cryopreservation in Patients Underwent Micro-TESE

For men with severe oligozoospermia, sperm cryopreservation can preserve surgically obtained sperm. How to cryopreserve single sperm in men is still a hot topic in assisted reproduction technology. Aim to analyze the laboratory and pregnancy outcomes of single sperm cryopreservation group, we retrospectively selected 38 cycles underwent single sperm cryopreservation and thawing as the study group and 618 cycles underwent conventional sperm cryopreservation and thawing as the control group, which were performed in the reproductive medicine center of the Sixth Affiliated Hospital, Sun Yatsen University, from April 2014 to October 2023. All the sperm came from microdissection testicular sperm extraction (micro-TESE), and performed intracytoplasmic sperm injection (ICSI) for fertilization. Zygotes were cultured to Day 3 embryo, which were freshly transferred to female uterus. Surplus embryos were cultured to blastosphere and cryopreserved. There was no statistical difference in female/male age, female BMI, infertility duration and female basal sex hormone (FSH, LH E2, AMH), No. of oocytes retrieved per cycle, No. of ICSI oocytes per cycle and No. of embryos transferred per cycle between the two groups (P > 0.05). No significant difference was found in two-pronuclear oocyte fertilization rate (59.23% VS 58.84%), Day 3 available embryo rate (61.81% VS 63.55%), Day 3 good-quality embryo rate (45.73% VS 50.27%), blastocyst formation rate (47.83% VS 49.46%), the implantation rate (47.37% VS 52.16%), clinical pregnancy rate (36.84% VS 47.18%), miscarriage rate (14.29% VS 12.68%) and live birth rate (85.71% VS 81.70%) between two groups (P > 0.05). In conclusion, single-sperm cryopreservation was the optimal method to preserve sperm after micro-TESE. It can increase the utilization of each sperm and lead to clinical pregnancy.

Microdissection testicular sperm extraction： an update

Patients with non-obstructive azoospermia （NOA） were once considered to be infertile with few treatment options due to the absence of sperm in the ejaculate. In the last two decades, the advent of intracytoplasmic sperm injection （ICSI）, and the application of various testicular sperm retrieval techniques, including fine needle aspiration （FNA）, conventional testicular sperm extraction （TESE） and microdissection testicular sperm extraction （micro-TESE） have revolutionized treatment in this group of men. Because most men with NOA will have isolated regions of spermatogenesis within the testis, studies have illustrated that sperm can be retrieved in most men with NOA, including Klinefelter＇s syndrome （KS）, prior history of chemotherapy and cryptorchidism. Micro-TESE, when compared with conventional TESE has a higher sperm retrieval rate （SRR） with fewer postoperative complications and negative effects on testicular function. In this article, we will compare the efficacy of the different procedures of sperm extraction, discuss the medical treatment and the role of testosterone optimization in men with NOA and describe the micro-TESE surgical technique. Furthermore, we will update our overall experience to allow counseling on the prognosis of sperm retrieval for the specific subsets of NOA.

多因素分析预测来曲唑提高非梗阻性无精子症和隐匿性无精子症患者精子密度研究

We tested the hypothesis that letrozole increases sperm count in non-obstructive azoospermic or cryptozoospermic patients with a testosterone （T）/17-beta-2-oestradiol （E2） ratio 〈 10. Forty-six patients with no chromosomal aberrations were randomized into two groups： 22 received letrozole 2.5 mg per day for 6 months （Group 1：6 azoospermic＋ 16 cryptozoospermic patients）, while 24 received a placebo （Group 2：5 azoospermic＋19 cryptozoospermic patients）. The following data were collected： two semen analyses, clinical history, scrotal Duplex scans, body mass index （BMI）, Y microdeletion, karyotype and cystic fibrosis screens and follicle-stimulating hormone （FSH）, luteinizing hormone （LH）, E2, T and prolactin levels. Both before and after letrozole or placebo administration, the patients underwent two semen analyses and hormonal assessments. The differences were evaluated using the Mann-Whitney Utest. The relationships between sperm concentration after letrozole administration with respect to FSH, TIE2 ratio, bilateral testicle volume and BMI before letrozole administration were assessed using multivariate analysis. The side effects were assessed using the chi-square test. Group 1 had sperm concentration （medians： 400-1.290× 10^6 ml^-1; P〈0.01） and motility （medians： class A from 2% to 15%; P〈0.01）, FSH, LH and T significantly increased, while Group 2 did not. E2 levels diminished significantly in Group 1, but not in Group 2. Eight patients in Group 1 demonstrated side effects, whereas no patient side effects were observed in Group 2. The sperm concentration after letrozole administration is inversely related to TIE2, FSH and BMI; a direct relationship emerged between sperm concentration and testicular volume.

Testis sperm extraction

The last 20 years have produced developments in the treatment for patients with non-obstructive azoospermia(NOA)who were once considered to be infertile.The combination of intracytoplasmic sperm injection together with various testicular sperm retrieval techniques,including conventional testicular sperm extraction(TESE),microdissection TESE(micro-TESE)and fine needle aspiration(FNA),have revolutionized treatment for these men.In men with NOA,isolated regions of spermatogenesis within the testis are common.The goal for all types of sperm retrieval procedures is locating the focal region(s)of spermatogenesis,and harvesting the sperm for assisted reproduction.This review article explores the surgical management of men with NOA and describes all techniques that can be used for testicular sperm retrieval.A PubMed search was conducted using the key words:“sperm extraction”,“NOA”,“testicular FNA”,“testicular mapping”,“TESE”,and“testicular biopsy”.All articles were reviewed.Articles were included if they provided data on sperm retrieval rates.The methods for performing sperm retrieval rates and outcomes of the various techniques are outlined.Micro-TESE has a higher sperm retrieval rates with fewer postoperative complications and negative effects on testicular function compared with conventional TESE.

Proposed age-stratified reference intervals of FSH derived from normozoospermic men

Objective:To demonstrate that serum follicle-stimulating hormone(FSH)in men rises with age,and to explore FSH reference intervals of age-related partitioning.Methods:Men aged 20-50 years(n=1190)underwent semen analysis according to World Health Organization(2010)methods.Serum was frozen prior to measurement of FSH by using the Siemens ADVIA Centaur®XP immunoassay system.FSH central 95%intervals after logarithmic transformation based on age were derived from 1037 normozoospermic men.These were then applied to oligozoospermic and azoospermic men.Men producing azoospermic semen samples were further classified as having non-obstructive azoospermia by clinical diagnostic criteria,including genetic analysis and surgical exploration.Results:Serum FSH in normozoospermic men increased with age(P<0.05),and reference intervals were determined with 10-year brackets:21-30 years[(1.0-8.2)IU/L],31-40 years[(1.4-9.5)IU/L],41-50 years[(1.9-12.0)IU/L].The proportion of oligozoospermic men with normal FSH concentrations was less than the normozoospermic men,which in turn was lower among azoospermic men(both P<0.01).The azoospermic men were further broken down according to the nature of the azoospermia as either obstructive or non-obstructive azoospermia,and 86.4%(38/44)men with non-obstructive azoospermia had elevated serum FSH concentrations whereas only 6.7%(1/15)men with obstructive azoospermia had high FSH levels,and this was significantly different(P<0.01).Conclusions:FSH concentrations increase in men between 20-50 years,and clinical interpretation of serum FSH results in men must be made by using age-based reference intervals.

Is Takotsubo cardiomyopathy still looking for its own nosological identity?

Despite several efforts to provide a proper nosological framework for Takotsubo cardiomyopathy(TCM),this remains an unresolved matter in clinical practice.Several clinical,pathophysiologic and histologic findings support the conceivable hypothesis that TCM could be defined as a unique pathologic entity,rather than a distinct subset of myocardial infarction with non-obstructive coronary arteries.Further investigations are needed in order to define TCM with the most appropriate disease taxonomy.

New Cutoff for High Sensitivity Troponin to Better Risk Stratify Patients with Non-ST Elevated Myocardial Infarction

Background: The diagnosis of Non-ST Elevated Myocardial Infarction (NSTEMI) is dependent on elevation of high sensitivity troponin (Hs-troponin). The current cutoff point for Hs-troponin is highly sensitive but not specific for obstructive coronary artery disease (CAD). This study aims to determine the best cutoff point for diagnosing CAD in patients presented with NSTEMI. Methods: Our study included all patients admitted as NSTEMI that underwent coronary angiography (CAG). They were grouped into two groups: A and B. Group A has obstructive CAD of 70% or more stenosis and group B with non-obstructive CAD. Patients were assessed for their demographics, clinical history, laboratory and imaging results. Using SPSS version 22, the pooled cohort of patients were analyzed at significant level < 0.05 and the data were tested for significant correlations between two predetermined groups. Results: Group A comprised 87.6% of the patients and both groups had a median age of 53 years. In Group A, 91% were males, 54% diabetics, 54% hypertensives, and median Hs-troponin was 145 ng/L. While in group B, 88% were males, 39% diabetics, 60% hypertensives, and median Hs-troponin was 54 ng/L. There was significant correlation between the two groups in the percentage of diabetes and median troponin level (p < 0.05). A ROC curve has identified a level of 127 ng/dL as the best cutoff of Hs-troponin in detecting obstructive CAD (p = 0.03). Interestingly, 60% of patients in group B had alternative diagnoses. Conclusion: Hs-troponin is sensitive but less specific for obstructive CAD. However, increasing its cutoff value will improve its specificity.