Nodulisporic acid produces direct activation and positive allosteric modulation of AVR-14B, a glutamate-gated chloride channel from adult Brugia malayi.

Glutamate-gated chloride channels (GluCls) are unique to invertebrates and are targeted by macrocyclic lactones. In this study, we cloned an AVR-14B GluCl subunit from adult Brugia malayi, a causative agent of lymphatic filariasis in humans. To elucidate this channel's pharmacological properties, we used Xenopus laevis oocytes for expression and performed two-electrode voltage-clamp electrophysiology. The receptor was gated by the natural ligand L-glutamate (effective concentration, 50% [EC50] = 0.4 mM) and ivermectin (IVM; EC50 = 1.8 nM). We also characterized the effects of nodulisporic acid (NA) on Bma-AVR-14B and NA-produced dual effects on the receptor as an agonist and a type II positive allosteric modulator. Here we report characterization of the complex activity of NA on a nematode GluCl. Bma-AVR-14B demonstrated some unique pharmacological characteristics. IVM did not produce potentiation of L-glutamate-mediated responses but instead, reduced the channel's sensitivity for the ligand. Further electrophysiological exploration showed that IVM (at a moderate concentration of 0.1 nM) functioned as an inhibitor of both agonist and positive allosteric modulatory effects of NA. This suggests that IVM and NA share a complex interaction. The pharmacological properties of Bma-AVR-14B indicate that the channel is an important target of IVM and NA. In addition, the unique electrophysiological characteristics of Bma-AVR-14B could explain the observed variation in drug sensitivities of various nematode parasites. We have also shown the inhibitory effects of IVM and NA on adult worm motility using Worminator. RNA interference (RNAi) knockdown suggests that AVR-14 plays a role in influencing locomotion in B. malayi.

A Phytophthora infestans RXLR effector AVR8 suppresses plant immunity by targeting a desumoylating isopeptidase DeSI2.

The potato's most devastating disease is late blight, which is caused by Phytophthora infestans. Whereas various resistance (R) genes are known, most are typically defeated by this fast-evolving oomycete pathogen. However, the broad-spectrum and durable R8 is a vital gene resource for potato resistance breeding. To support an educated deployment of R8, we embarked on a study on the corresponding avirulence gene Avr8. We overexpressed Avr8 by transient and stable transformation, and found that Avr8 promotes colonization of P. infestans in Nicotiana benthamiana and potato, respectively. A yeast-two-hybrid (Y2H) screen showed that AVR8 interacts with a desumoylating isopeptidase (StDeSI2) of potato. We overexpressed DeSI2 and found that DeSI2 positively regulates resistance to P. infestans, while silencing StDeSI2 downregulated the expression of a set of defense-related genes. By using a specific proteasome inhibitor, we found that AVR8 destabilized StDeSI2 through the 26S proteasome and attenuated early PTI responses. Altogether, these results indicate that AVR8 manipulates desumoylation, which is a new strategy that adds to the plethora of mechanisms that Phytophthora exploits to modulate host immunity, and StDeSI2 provides a new target for durable resistance breeding against P. infestans in potato.

Identification of Candidate Avirulence and Virulence Genes Corresponding to Stem Rust (Puccinia graminis f. sp. tritici) Resistance Genes in Wheat.

Stem rust, caused by the biotrophic fungal pathogen Puccinia graminis f. sp. tritici (Pgt), is an important disease of wheat. However, the majority of Pgt virulence/avirulence loci and underlying genes remain uncharacterized due to the constraints of developing bi-parental populations with this obligate biotroph. Genome-wide association studies (GWAS) using a sexual Pgt population mainly collected from the Pacific Northwestern United States were used to identify candidate virulence/avirulence effector genes corresponding to the six wheat Sr genes: Sr5, Sr21, Sr8a, Sr17, Sr9a, and Sr9d. The Pgt isolates were genotyped using whole-genome shotgun sequencing that identified approximately 1.2 million single nucleotide polymorphisms (SNPs) and were phenotyped at the seedling stage on six Sr gene differential lines. Association mapping analyses identified 17 Pgt loci associated with virulence or avirulence phenotypes on six Pgt resistance genes. Among these loci, 16 interacted with a specific Sr gene, indicating Sr-gene specific interactions. However, one avirulence locus interacted with two separate Sr genes (Sr9a and Sr17), suggesting two distinct Sr genes identifying a single avirulence effector. A total of 24 unique effector gene candidates were identified, and haplotype analysis suggests that within this population, AvrSr5, AvrSr21, AvrSr8a, AvrSr17, and AvrSr9a are dominant avirulence genes, while avrSr9d is a dominant virulence gene. The putative effector genes will be fundamental for future effector gene cloning efforts, allowing for further understanding of rust effector biology and the mechanisms underlying virulence evolution in Pgt with respect to race-specific R-genes. [Formula: see text] Copyright © 2024 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.

Sequential breakdown of the Cf-9 leaf mould resistance locus in tomato by Fulvia fulva.

Leaf mould, caused by Fulvia fulva, is a devastating disease of tomato plants. In many commercial tomato cultivars, resistance to this disease is governed by the Cf-9 locus, which encodes five paralogous receptor-like proteins. Two of these proteins confer resistance: Cf-9C recognises the previously identified F. fulva effector Avr9 and provides resistance during all plant growth stages, while Cf-9B recognises the yet-unidentified F. fulva effector Avr9B and provides mature plant resistance only. In recent years, F. fulva strains have emerged that can overcome the Cf-9 locus, with Cf-9C circumvented through Avr9 deletion. To understand how Cf-9B is circumvented, we set out to identify Avr9B. Comparative genomics, transient expression assays and gene complementation experiments were used to identify Avr9B, while gene sequencing was used to assess Avr9B allelic variation across a world-wide strain collection. A strict correlation between Avr9 deletion and resistance-breaking mutations in Avr9B was observed in strains recently collected from Cf-9 cultivars, whereas Avr9 deletion but no mutations in Avr9B were observed in older strains. This research showcases how F. fulva has evolved to sequentially break down the Cf-9 locus and stresses the urgent need for commercial tomato cultivars that carry novel, stacked resistance genes active against this pathogen.

Management of severe aortic stenosis in the presence of an 8 mm right coronary stent protrusion.

Management of a protruding coronary stent into the aortic root in patients undergoing evaluation for transcatheter aortic valve replacement can be challenging. We describe a patient treated with stent trimming and surgical aortic valve replacement, highlighting the importance of a multidisciplinary evaluation and selection process in this complex scenario.

Early predictors of severe left main and/or three-vessel disease in patients with non-ST-segment elevation myocardial infarction: A dual-center retrospective study.

BACKGROUND: Early detection of patients concomitant with left main and/or three-vessel disease (LM/3VD) and high SYNTAX score (SS) is crucial for determining the most effective revascularization options regarding the use of antiplatelet medications and prognosis risk stratification. However, there is a lack of study for predictors of LM/3VD with SS in patients with non-ST-segment elevation myocardial infarction (NSTEMI). We aimed to identify potential factors that could predict LM/3VD with high SS (SS > 22) in patients with NSTEMI. METHODS: This dual-center retrospective study included a total of 481 patients diagnosed with NSTEMI who performed coronary angiography procedures. Clinical factors on admission were collected. The patients were divided into non-LM/3VD, Nonsevere LM/3VD (SS ≤ 22), and Severe LM/3VD (SS > 22) groups. To identify independent predictors, Univariate and logistic regression analyses were conducted on the clinical parameters. RESULTS: A total of 481 patients were included, with an average age of 60.9 years and 75.9% being male. Among these patients, 108 individuals had severe LM/3VD. Based on the findings of a multivariate logistic regression analysis, the extent of ST-segment elevation observed in lead aVR (OR: 7.431, 95% CI: 3.862-14.301, p < .001) and age (OR: 1.050, 95% CI: 1.029-1.071, p < .001) were identified as independent predictors of severe LM/3VD. CONCLUSION: This study indicated that the age of patients and the extent of ST-segment elevation observed in lead aVR on initial electrocardiogram were the independent predictive factors of LM/3VD with high SS in patients with NSTEMI.

Bi-National Outcomes of Redo Surgical Aortic Valve Replacement in the Era of Valve-in-Valve Transcatheter Aortic Valve.

BACKGROUND: Implantation of bioprosthetic valves is more common as the population ages and there is a shift towards implanting bioprosthetic aortic valves in an increasingly younger surgical population. Bioprosthetic heart valve insertion, however, carries the long-term risk of valve failure through structural valve degeneration. Re-operative surgical aortic valve replacement has historically been the only definitive management option for patients with prosthetic valve dysfunction, however, data on the short- and long-term outcomes following re-operative surgery in Australia and New Zealand is limited. METHOD: Data on all patients who underwent redo aortic valve surgery, over a 20-year period (up to 2021) was obtained from the Australian and New Zealand Society of Cardiothoracic Surgery Registry. RESULTS: A total of 1,199 patients (770 males; 64.2% and 429 females; 35.8%) were included in the overall analysis. The 30-day mortality was 6.4% with operative urgency status the most important risk factor for peri-operative mortality. The long-term survival rate of 1,145 patients was 90.5% (95% confidence interval [CI] 88.8%-92.3%), 77% (95% CI 73.9%-80.2%) and 57.2% (95% CI 55.2%-62.8%) at 1-, 5- and 10-years post-procedure, respectively, with a median survival of 12.7 years. Pre-existing chronic kidney disease was strongly associated with poorer long-term survival. For patients under 70 years of age the 1-, 5- and 10-year survival rates were 92.9% (95% CI 90.9%-95.1%), 83.6% (95% CI 80.1%-87.3%) and 73.1% (95% CI 67.4%-79.3%), respectively. CONCLUSIONS: The results from this registry study indicate that in Australia and New Zealand, a repeat surgical aortic valve replacement can result in a relatively low mortality rate, serving as a reference point for medical procedures in these regions.

AVR/I/SSAPDB: a comprehensive & specialised knowledgebase of antimicrobial peptides to combat VRSA, VISA, and VSSA.

The rise of multi-drug resistant (MDR) bacteria, especially strains of Staphylococcus aureus like Vancomycin-resistant S. aureus (VRSA), Vancomycin-intermediate S. aureus (VISA), and Vancomycin-susceptible S. aureus (VSSA), poses a severe threat to global health. This situation underscores the urgent need for novel antimicrobial agents to combat these resistant strains effectively. Here, we are introducing the Anti-Vancomycin-Resistant/Intermediate/Susceptible Staphylococcus aureus Peptide Database (AVR/I/SSAPDB), a manually curated comprehensive and specialised knowledgebase dedicated to antimicrobial peptides (AMPs) that target VRSA, VISA, and VSSA with clinical and non-clinical significance. Our database sources data from PubMed, cataloging 491 experimentally validated AMPs with detailed annotations on peptides, activity, and cross-references to external databases like PubMed, UniProt, PDB, and DrugBank. AVR/I/SSAPDB offers a user-friendly interface with simple to advanced and list-based search capabilities, enabling researchers to explore AMPs against VRSA, VISA, and VSSA. We are hoping that this resource will be helpful to the scientific community in developing targeted peptide-based therapeutics, providing a crucial tool for combating VRSA, VISA, and VSSA, and addressing a major public health concern. AVR/I/SSAPDB is freely accessible via any web-browser at URL: https://bblserver.org.in/avrissa/ .

A dominant-negative avirulence effector of the barley powdery mildew fungus provides mechanistic insight into barley MLA immune receptor activation.

Nucleotide-binding leucine-rich repeat receptors (NLRs) recognize pathogen effectors to mediate plant disease resistance often involving host cell death. Effectors escape NLR recognition through polymorphisms, allowing the pathogen to proliferate on previously resistant host plants. The powdery mildew effector AVRA13-1 is recognized by the barley NLR MLA13 and activates host cell death. We demonstrate here that a virulent form of AVRA13, called AVRA13-V2, escapes MLA13 recognition by substituting a serine for a leucine residue at the C-terminus. Counterintuitively, this substitution in AVRA13-V2 resulted in an enhanced MLA13 association and prevented the detection of AVRA13-1 by MLA13. Therefore, AVRA13-V2 is a dominant-negative form of AVRA13 and has probably contributed to the breakdown of Mla13 resistance. Despite this dominant-negative activity, AVRA13-V2 failed to suppress host cell death mediated by the MLA13 autoactive MHD variant. Neither AVRA13-1 nor AVRA13-V2 interacted with the MLA13 autoactive variant, implying that the binding moiety in MLA13 that mediates association with AVRA13-1 is altered after receptor activation. We also show that mutations in the MLA13 coiled-coil domain, which were thought to impair Ca2+ channel activity and NLR function, instead resulted in MLA13 autoactive cell death. Our results constitute an important step to define intermediate receptor conformations during NLR activation.

Transcatheter Aortic Valve Replacement in Special Populations.

Since its food and drug administration (FDA) approval in 2011, transcatheter aortic valve replacement (TAVR) has revolutionized the highly prevalent disease of aortic stenosis. In this review, we present a comprehensive overview of the data and considerations for utilization of TAVR in special populations who were either excluded from or not adequately represented in the seminal TAVR trials, due to high-risk valvular and/or systemic factors. These include nonagenarians, patients with renal dysfunction, chronic thrombocytopenia, bicuspid aortic valve, rheumatic valve disease, patients with failed aortic valve bioprosthesis requiring valve-in-valve intervention and patients with mixed aortic valve disease. In short, TAVR is a feasible therapeutic strategy in high-risk and special populations with mortality benefit and improvement in quality of life. Randomized controlled trials in high-risk populations are recommended to confirm results from observational studies.

Chest pain with ST-elevation in leads AVR, III, AVF, V1, V3R, V4R and V5R.

We mistakenly diagnosed a patient with pulmonary embolism as ST-elevation acute myocardial infarction. The case complained of chest pain with ST-elevation in leads AVR, III, AVF, V1, V3R, V4R and V5R. In addition, we also found ST- elevation AVR, III>ST- elevation AVF, QIII>QAVF and QV1. Multi-site pulmonary embolism can lead to type 2 myocardial infarction or special type of myocardial infarction with non-obstructive coronary arteries through multiple pathological mechanisms.

Right fascicular blocks: A case series and a comprehensive electrocardiographic analysis.

The main trunk of the right bundle branch divides into an anterior, middle (lateral) and posterior fascicle. This article describes the right anterior and posterior fascicular block. They present a diagnostic challenge and are often overlooked during diagnostic processes. The studied patients were young adults whose electrocardiographic tracings were registered at the Mexican Faculty of Medicine of La Salle University. The presence of delayed R-peak time in aVR and V1, along with the described ventricular complex morphologies, and a right or left deviation of the cardiac axis exceeding +60°, may be suggestive of right fascicular blocks.

Myocardial infarction due to left main coronary artery total occlusion: A unique electrocardiographic presentation.

Left main coronary artery (LMCA) total occlusion typically presents as anterolateral ST-segment myocardial infarction with or without right bundle branch block with left anterior fascicular block, and ST-segment elevation in aVR. On the contrary to the previously described electrocardiographic pattern we describe a distinct electrocardiographic presentation in a patient with total LMCA occlusion characterized by the presence of complete LBBB co-existing with upsloping ST-segment depression in precordial leads leading to symmetrical, tall, positive T waves, the so called de Winter's sign.

Insertion of Transposable Elements in AVR-Pib of Magnaporthe oryzae Leading to LOSS of the Avirulent Function.

Rice blast is a very serious disease caused by Magnaporthe oryzae, which threatens rice production and food supply throughout the world. The avirulence (AVR) genes of rice blast are perceived by the corresponding rice blast resistance (R) genes and prompt specific resistance. A mutation in AVR is a major force for new virulence. Exploring mutations in AVR among M. oryzae isolates from rice production fields could aid assessment of the efficacy and durability of R genes. We studied the probable molecular-evolutionary patterns of AVR-Pib alleles by assaying their DNA-sequence diversification and examining their avirulence to the corresponding Pib resistance gene under natural conditions in the extremely genetically diverse of rice resources of Yunnan, China. PCRs detected results from M. oryzae genomic DNA and revealed that 162 out of 366 isolates collected from Yunnan Province contained AVR-Pib alleles. Among them, 36.1-73.3% isolates from six different rice production areas of Yunnan contained AVR-Pib alleles. Furthermore, 36 (28.6%) out of 126 isolates had a transposable element (TE) insertion in AVR-Pib, which resulted in altered virulence. The TE insertion was identified in isolates from rice rather than from Musa nana Lour. Twelve AVR-Pib haplotypes encoding three novel AVR-Pib variants were identified among the remaining 90 isolates. AVR-Pib alleles evolved to virulent forms from avirulent forms by base substitution and TE insertion of Pot2 and Pot3 in the 5' untranslated region of AVR-Pib. These findings support the hypothesis that functional AVR-Pib possesses varied sequence structures and can escape surveillance by hosts via multiple variation manners.

Lp(a) in the Pathogenesis of Aortic Stenosis and Approach to Therapy with Antisense Oligonucleotides or Short Interfering RNA.

To date, no medical therapy can slow the progression of aortic stenosis. Fibrocalcific stenosis is the most frequent form in the general population and affects about 6% of the elderly population. Over the years, diagnosis has evolved thanks to echocardiography and computed tomography assessments. The application of artificial intelligence to electrocardiography could further implement early diagnosis. Patients with severe aortic stenosis, especially symptomatic patients, have valve repair as their only therapeutic option by surgical or percutaneous technique (TAVI). The discovery that the pathogenetic mechanism of aortic stenosis is similar to the atherosclerosis process has made it possible to evaluate the hypothesis of medical therapy for aortic stenosis. Several drugs have been tested to reduce low-density lipoprotein (LDL) and lipoprotein(a) (Lp(a)) levels, inflammation, and calcification. The Proprotein Convertase Subtilisin/Kexin type 9 inhibitors (PCSK9-i) could decrease the progression of aortic stenosis and the requirement for valve implantation. Great interest is related to circulating Lp(a) levels as causally linked to degenerative aortic stenosis. New therapies with ASO (antisense oligonucleotides) and siRNA (small interfering RNA) are currently being tested. Olpasiran and pelacarsen reduce circulating Lp(a) levels by 85-90%. Phase 3 studies are underway to evaluate the effect of these drugs on cardiovascular events (cardiovascular death, non-fatal myocardial injury, and non-fatal stroke) in patients with elevated Lp(a) and CVD (cardiovascular diseases). For instance, if a reduction in Lp(a) levels is associated with aortic stenosis prevention or progression, further prospective clinical trials are warranted to confirm this observation in this high-risk population.

Sutureless Aortic Valve Prosthesis in Redo Procedures: Single-Center Experience.

Background and Objectives: Sutureless aortic valve prostheses have presented favorable hemodynamic performance while facilitating minimally invasive access approaches. As the population ages, the number of patients at risk for aortic valve reoperation constantly increases. The aim of the present study is to present our single-center experience in sutureless aortic valve replacement (SU-AVR) in reoperations. Materials and Methods: The data of 18 consecutive patients who underwent SU-AVR in a reoperation between May 2020 and January 2023 were retrospectively analyzed. Results: The mean age of the patients was 67.9 ± 11.1 years; patients showed a moderate-risk profile with a median logistic EuroSCORE II of 7.8 (IQR of 3.8-32.0) %. The implantation of the Perceval S prosthesis was technically successful in all patients. The mean cardiopulmonary bypass time was 103.3 ± 50.0 min, and the cross-clamp time was 69.1 ± 38.8 min. No patients required a permanent pacemaker implantation. The postoperative gradient was 7.3 ± 2.4 mmHg, and no cases of paravalvular leakage were observed. There was one case of intraprocedural death, while the thirty-day mortality was 11%. Conclusions: Sutureless bioprosthetic valves tend to simplify the surgical procedure of a redo AVR. By maximizing the effective orifice area, sutureless valves may present an important advantage, being a safe and effective alternative not only to traditional surgical prostheses but also to transcatheter valve-in-valve approaches in select cases.

Outcomes of emergent cardiac surgery after transcatheter aortic valve implantation.

OBJECTIVE: The aim of this study was to evaluate the reasons for emergent cardiac surgery (ECS) after transcatheter aortic valve implantation (TAVI) and assess outcomes of these patients. METHODS: All patients undergoing ECS following a complicated TAVI procedure at a high-volume TAVI centre in the Netherlands from 1 January 2008 to 1 April 2022 were included. Baseline and procedural characteristics and outcome data (procedural, 30-day and 1­year mortality, in-hospital stroke, 30-day pacemaker implantation, 30-day vascular complications, 30-day deep sternal wound infections and 30-day re-exploration) were collected from patient files and analysed using descriptive statistics. RESULTS: During the study period, 16 of 1594 patients (1.0%) undergoing TAVI required ECS. The main reason for ECS was valve embolisation (n = 9; 56.3%), followed by perforation of the left/right ventricle with guide wire/pacemaker lead (n = 3; 18.8%) and annular rupture (n = 3; 18.8%). Procedural, 30-day and 1­year mortality was 0%, 18.8% (n = 3) and 31.3% (n = 5), respectively. In-hospital stroke occurred in 1 patient (6.3%), a pacemaker was implanted at 30 days in 2 patients (12.5%), and major vascular complications did not occur. CONCLUSION: ECS following complicated TAVI was performed in only a small number of cases. It had a high but acceptable perioperative and 30-day mortality, taking into account the otherwise lethal consequences. In case of valve embolisation, no periprocedural or 30-day mortality was observed for surgical aortic valve replacement (even in a redo setting), which supported the necessity to perform TAVI in centres with cardiac surgical backup on site.

aVR: The forgotten lead in acute coronary syndrome: A case series.

Lead aVR is often considered as a neglected lead or forgotten lead owing to its reciprocal location to the lateral leads. However, it has diagnostic and prognostic importance in cases of acute coronary syndromes. We present a series of four cases of acute coronary syndrome with ST elevation (STE) in aVR and critical stenosis in coronary vessels. Patients with STE in aVR have a poor prognosis with increased morbidity not limited to increased chances of heart failure at presentation, greater hemodynamic instability, and in-hospital acute kidney injury, as well as increased mortality due to large infarction areas. Thus, early revascularization is warranted in such cases.

Morpho-molecular diversity and avirulence genes distribution among the diverse isolates of Magnaporthe oryzae from Southern India.

AIMS: To investigate the diversity of eco-distinct isolates of Magnaporthe oryzae for their morphological, virulence and molecular diversity and relative distribution of five Avr genes. METHODS AND RESULTS: Fifty-two M. oryzae isolates were collected from different rice ecosystems of southern India. A majority of them (n = 28) formed a circular colony on culture media. Based on the disease reaction on susceptible cultivar (cv. HR-12), all 52 isolates were classified in to highly virulent (n = 28), moderately virulent (n = 11) and less-virulent (13) types. Among the 52 isolates, 38 were selected for deducing internal transcribed spacer (ITS) sequence diversity. For deducing phylogeny, another set of 36 isolates from other parts of the world was included, which yielded two distinct phylogenetic clusters. We identified eight haplotype groups and 91 variable sites within the ITS sequences, and haplotype-group-2 (Hap_2) was predominant (n = 24). The Tajima's and Fu's Fs neutrality tests exhibited many rare alleles. Furthermore, PCR analysis for detecting the presence of five Avr genes in the different M. oryzae isolates using Avr gene-specific primers in PCR revealed that Avr-Piz-t, Avr-Pik, Avr-Pia and Avr-Pita were present in 73.68%, 73.68%, 63.16% and 47.37% of the isolates studied, respectively; whereas, Avr-Pii was identified only in 13.16% of the isolates. CONCLUSIONS: Morpho-molecular and virulence studies revealed the significant diversity among eco-distinct isolates. PCR detection of Avr genes among the M. oryzae population revealed the presence of five Avr genes. Among them, Avr-Piz-t, Avr-Pik and Avr-Pia were more predominant. SIGNIFICANCE AND IMPACT OF THE STUDY: The study documented the morphological and genetic variability of eco-distinct M. oryzae isolates. This is the first study demonstrating the distribution of the Avr genes among the eco-distinct population of M. oryzae from southern India. The information generated will help plant breeders to select appropriate resistant gene/s combinations to develop blast disease-resistant rice cultivars.

Electrocardiographic patterns predict the presence of collateral circulation and in-hospital mortality in acute total left main occlusion.

BACKGROUND: Data on the clinical characteristics, electrocardiogram (ECG) findings and outcomes of patients with acute myocardial infarction (AMI) due to total unprotected left main (ULM) artery occlusion is limited. METHODS: Between 2009 and 2021, 44 patients with AMI due to total ULM occlusion underwent primary percutaneous coronary intervention (PCI) at our institution. The ECG, collateral circulation, clinical and procedural characteristics, and in-hospital mortality were retrospectively evaluated. RESULTS: Twenty five patients presented with shock and 18 patients had in-hospital mortality. Nineteen patients presented with ST-segment elevation myocardial infarction (STEMI), while 25 presented with non-ST-segment elevation myocardial infarction (NSTEMI). ST-segment elevation (STE) in I and STEMI were associated with the absence of collateral circulation, while STE in aVR was associated with its presence. In the NSTEMI group, patients with STE in both aVR and aVL showed more collateral filling of the left anterior descending coronary artery (LAD) territory, while patients with STE in aVR showed more collateral filling of the LAD and the left circumflex artery territory. Compared with total ULM occlusion, patients with partial ULM obstruction presented with more STE in aVR, less STE in aVR and aVL, and less STEMI. Shock, post-PCI TIMI 0-2 flow, non-STE in aVR, STEMI, and STE in I predicted in-hospital mortality. STEMI and the absence of collateral flow were significantly associated with shock. CONCLUSIONS: STE in the precordial leads predicted the absence of collateral circulation while STE in aVR and STE in both aVR and aVL predicted different collateral filling territories in ULM occlusion. STE in I, non-STE in aVR, and STEMI predicted in-hospital mortality in these patients.