Converging forms: an examination of sub-Arctic, circumarctic, and Central Asian Ranunculus auricomus agg. populations.

Introduction: Phenotypic complexity in species complexes and recently radiated lineages has resulted in a diversity of forms that have historically been classified into separate taxa. Increasingly, with the proliferation of high-throughput sequencing methods, additional layers of complexity have been recognized, such as frequent hybridization and reticulation, which may call into question the previous morphological groupings of closely related organisms. Methods: We investigated Northern European, Asian, and Beringian populations of Ranunculus auricomus agg. with phylogenomic analysis of 736 genes and 27,586 SNPs in order to deduce the interrelatedness and hybrid origin of this phenotypically and taxonomically complicated group from Europe characterized by a history of hybridization, polyploidy, apomixis, and recent radiation. The ploidy levels and the reproductive mode of the Northern European populations were assessed via flow cytometric seed screening. In addition, in order to examine the phenotypic plasticity of the dwarf forms previously described as species and summarized as the Ranunculus monophyllus group, we conducted climate chamber experiments under cold (northern) and warm (temperate) conditions. Results: The Northern European populations are tetra- to hexaploid and propagate primarily through apomixis. The complex is characterized by highly reticulate relationships. Genetic differentiation of the main clusters has occurred between the above-mentioned geographical regions. We find evidence for the hybrid origin of the taxa in these areas with differing genomic contributions from the geographically nearest European sexual progenitor species. Furthermore, polyphyly in the taxa of the R. monophyllus group is supported. Experiments show low lability in the traits associated with the R. monophyllus group. Discussion: We conclude that multiple adaptations of hybrids to colder climates and shorter vegetation periods have shaped the phenotypes of the R. monophyllus group, and we suggest a formal classification as nothotaxa within the R. auricomus group.

Species delimitation 4.0: integrative taxonomy meets artificial intelligence.

Although species are central units for biological research, recent findings in genomics are raising awareness that what we call species can be ill-founded entities due to solely morphology-based, regional species descriptions. This particularly applies to groups characterized by intricate evolutionary processes such as hybridization, polyploidy, or asexuality. Here, challenges of current integrative taxonomy (genetics/genomics + morphology + ecology, etc.) become apparent: different favored species concepts, lack of universal characters/markers, missing appropriate analytical tools for intricate evolutionary processes, and highly subjective ranking and fusion of datasets. Now, integrative taxonomy combined with artificial intelligence under a unified species concept can enable automated feature learning and data integration, and thus reduce subjectivity in species delimitation. This approach will likely accelerate revising and unraveling eukaryotic biodiversity.

Phylogenomics of Southern European Taxa in the Ranunculus auricomus Species Complex: The Apple Doesn't Fall Far from the Tree.

The taxonomic status of many Southern European taxa of the Ranunculus auricomus complex remains uncertain despite this region's proximity to the native ranges of the sexual progenitor species of the complex. We investigated whether additional sexual progenitor species are present in the Mediterranean region. Utilizing target enrichment of 736 single-copy nuclear gene regions and flow cytometry, we analyzed phylogenomic relationships, the ploidy level, and the reproductive mode in representatives of 16 populations in Southern Europe, with additional sequence data from herbarium collections. Additionally, phased sequence assemblies from suspected nothotaxa were mapped to previously described sexual progenitor species in order to determine hybrid ancestry. We found the majority of Mediterranean taxa to be tetraploid, with hybrid populations propagating primarily via apomixis. Phylogenomic analysis revealed that except for the progenitor species, the Mediterranean taxa are often polyphyletic. Most apomictic taxa showed evidence of mixed heritage from progenitor species, with certain progenitor genotypes having mapped more to the populations from adjacent geographical regions. Geographical trends were found in phylogenetic distance, roughly following an east-to-west longitudinal demarcation of the complex, with apomicts extending to the southern margins. Additionally, we observed post-hybridization divergence between the western and eastern populations of nothotaxa in Southern Europe. Our results support a classification of apomictic populations as nothotaxa, as previously suggested for Central Europe.

Geometric Morphometric Versus Genomic Patterns in a Large Polyploid Plant Species Complex.

Plant species complexes represent a particularly interesting example of taxonomically complex groups (TCGs), linking hybridization, apomixis, and polyploidy with complex morphological patterns. In such TCGs, mosaic-like character combinations and conflicts of morphological data with molecular phylogenies present a major problem for species classification. Here, we used the large polyploid apomictic European Ranunculus auricomus complex to study relationships among five diploid sexual progenitor species and 75 polyploid apomictic derivate taxa, based on geometric morphometrics using 11,690 landmarked objects (basal and stem leaves, receptacles), genomic data (97,312 RAD-Seq loci, 48 phased target enrichment genes, 71 plastid regions) from 220 populations. We showed that (1) observed genomic clusters correspond to morphological groupings based on basal leaves and concatenated traits, and morphological groups were best resolved with RAD-Seq data; (2) described apomictic taxa usually overlap within trait morphospace except for those taxa at the space edges; (3) apomictic phenotypes are highly influenced by parental subgenome composition and to a lesser extent by climatic factors; and (4) allopolyploid apomictic taxa, compared to their sexual progenitor, resemble a mosaic of ecological and morphological intermediate to transgressive biotypes. The joint evaluation of phylogenomic, phenotypic, reproductive, and ecological data supports a revision of purely descriptive, subjective traditional morphological classifications.

Reticulate Evolution in the Western Mediterranean Mountain Ranges: The Case of the Leucanthemopsis Polyploid Complex.

Polyploidization is one of the most common speciation mechanisms in plants. This is particularly relevant in high mountain environments and/or in areas heavily affected by climatic oscillations. Although the role of polyploidy and the temporal and geographical frameworks of polyploidization have been intensively investigated in the alpine regions of the temperate and arctic biomes, fewer studies are available with a specific focus on the Mediterranean region. Leucanthemopsis (Asteraceae) consists of six to ten species with several infraspecific entities, mainly distributed in the western Mediterranean Basin. It is a polyploid complex including montane, subalpine, and strictly alpine lineages, which are locally distributed in different mountain ranges of Western Europe and North Africa. We used a mixed approach including Sanger sequencing and (Roche-454) high throughput sequencing of amplicons to gather information from single-copy nuclear markers and plastid regions. Nuclear regions were carefully tested for recombinants/PCR artifacts and for paralogy. Coalescent-based methods were used to infer the number of polyploidization events and the age of formation of polyploid lineages, and to reconstruct the reticulate evolution of the genus. Whereas the polyploids within the widespread Leucanthemopsis alpina are autopolyploids, the situation is more complex among the taxa endemic to the western Mediterranean. While the hexaploid, L. longipectinata, confined to the northern Moroccan mountain ranges (north-west Africa), is an autopolyploid, the Iberian polyploids are clearly of allopolyploid origins. At least two different polyploidization events gave rise to L. spathulifolia and to all other tetraploid Iberian taxa, respectively. The formation of the Iberian allopolyploids took place in the early Pleistocene and was probably caused by latitudinal and elevational range shifts that brought into contact previously isolated Leucanthemopsis lineages. Our study thus highlights the importance of the Pleistocene climatic oscillations and connected polyploidization events for the high plant diversity in the Mediterranean Basin.

Ancient DNA extraction methods for herbarium specimens: When is it worth the effort?

Premise: Herbaria harbor a tremendous number of plant specimens that are rarely used for molecular systematic studies, largely due to the difficulty in extracting sufficient amounts of high-quality DNA from the preserved plant material. Methods: We compared the standard Qiagen DNeasy Plant Mini Kit and a specific protocol for extracting ancient DNA (aDNA) (the N-phenacylthiazolium bromide and dithiothreitol [PTB-DTT] extraction method) from two different plant genera (Xanthium and Salix). The included herbarium materials covered about two centuries of plant collections. To analyze the success of DNA extraction using each method, a subset of samples was subjected to a standard library preparation as well as target-enrichment approaches. Results: The PTB-DTT method produced a higher DNA yield of better quality than the Qiagen kit; however, extracts from the Qiagen kit over a certain DNA yield and quality threshold produced comparable sequencing results. The sequencing resulted in high proportions of endogenous reads. We were able to successfully sequence 200-year-old samples. Discussion: This method comparison revealed that, for younger specimens, DNA extraction using a standard kit might be sufficient. For old and precious herbarium specimens, aDNA extraction methods are better suited to meet the requirements for next-generation sequencing.

Untying Gordian knots: unraveling reticulate polyploid plant evolution by genomic data using the large Ranunculus auricomus species complex.

Speciation via hybridization and polyploidization is a major evolutionary force in plant evolution but is still poorly understood for neopolyploid groups. Challenges are attributed to high heterozygosity, low genetic divergence, and missing information on progenitors, ploidy, and reproduction. We study the large Eurasian Ranunculus auricomus species complex and use a comprehensive workflow integrating reduced-representation sequencing (RRS) genomic data to unravel reticulate evolution, genome diversity and composition of polyploids. We rely on 97 312 restriction site-associated DNA sequencing (RAD-Seq) loci, 576 targeted nuclear genes (48 phased), and 71 plastid regions derived from 78 polyploid apomictic taxa and four diploid and one tetraploid putative sexual progenitor species. We applied (phylo)genomic structure, network, and single nucleotide polymorphism (SNP)-origin analyses. Results consistently showed only 3-5 supported and geographically structured polyploid genetic groups, each containing extant sexual and one unknown progenitor species. Combined analyses demonstrated predominantly allopolyploid origins, each involving 2-3 different diploid sexual progenitor species. Young allotetraploids were characterized by subgenome dominance and nonhybrid SNPs, suggesting substantial post-origin but little lineage-specific evolution. The biodiversity of neopolyploid complexes can result from multiple hybrid origins involving different progenitors and substantial post-origin evolution (e.g. homoeologous exchanges, hybrid segregation, gene flow). Reduced-representation sequencing genomic data including multi-approach information is efficient to delimit shallow reticulate relationships.

[Staged rotational atherectomy in a patient with acute ST-elevation myocardial infarction: a case report and review of the literature]. / Aterectomia rotazionale e strategia "Rota-staged PCI" in un paziente con infarto miocardico acuto e sopraslivellamento del tratto ST: caso clinico e revisione della letteratura.

Rotational atherectomy represents an option to improve the treatment of calcified/undilatable coronary stenoses, but its use in ST-elevation myocardial infarction (STEMI) is controversial. We report the case of a patient with an occlusive and calcified coronary stenosis and its management not previously described. A 67-year-old man with STEMI was referred to our cath-lab. Coronary angiography showed a complex calcified and thrombotic occlusion of the right coronary artery. Vessel patency was obtained with balloon dilation, achieving clinical stability. The patient started dual antiplatelet therapy and was scheduled for a staged procedure using rotational atherectomy ("Rota-staged PCI"), performed 6 days later reaching optimal angiographic and clinical results. Our purpose was to manage this STEMI patient with an occluded and heavily calcified coronary artery in two times: a primary coronary angioplasty to quickly reopen the artery and an early staged PCI using rotational atherectomy to optimize the intervention (coronary dilation and stent deployment) minimizing the risk of stent underexpansion or acute complications.

Moving beyond assumptions: Polyploidy and environmental effects explain a geographical parthenogenesis scenario in European plants.

Geographical parthenogenesis (GP) describes the phenomenon that apomicts tend to have larger distribution areas and/or occur at higher altitudes or latitudes compared to sexual relatives. However, the complex effects of genome-wide heterozygosity, ploidy, reproduction mode (sexual vs. apomictic), and environment shaping GP of plants are still not well understood. We ascertained ploidy and reproduction mode by flow cytometry of 221 populations, and added genomic RADseq data (maximum 33,165 loci) of 80 taxa of the Ranunculus auricomus polyploid plant complex in temperate Europe. We observed 7% mainly diploid sexual, 28% facultative apomictic (mean sexuality 7.1%), and 65% obligate apomictic populations. Sexuals occupied a more southern, smaller distribution area, whereas apomicts expanded their range to higher latitudes. Within the complex, we detected three main genetic clusters and highly reticulate relationships. A genetically-informed path analysis using GLMMs revealed several significant relationships. Sexuality of populations (percent of sexual seeds) was higher in diploids compared to polyploids, associated with more petals, and similar between forests and open habitats. In contrast to other apomictic plant complexes, sexuality was mainly positively correlated to solar radiation and isothermality, which fits the southern distribution. We found up to three times higher heterozygosity in polyploids compared to diploids, and generally more heterozygous individuals in forests compared with open habitats. Interestingly, we revealed a previously unknown positive association between heterozygosity and temperature seasonality, suggesting a higher resistance of polyploids to more extreme climatic conditions. We provide empirical evidence for intrinsic and extrinsic factors shaping the GP pattern in a polyploid plant complex.

On the Leucanthemopsis alpina (L.) Heywood growing in the Illyrian region.

Leucanthemopsis alpina (L.) Heywood (Asteraceae, Anthemideae) is a small, caespitose plant growing in high alpine environments in all the main southern European mountain ranges. However, the species status in the Balkan Peninsula (and especially in the Dinaric Alps) is not very well known. Surrounding this area, different L. alpina subspecies are found in the Eastern Alps and in the Carpathians. These subspecies differ from one another, both morphologically and in chromosome number. The present study aims to better characterise the populations of L. alpina in the Illyrian and Balkan regions by undertaking a comprehensive survey of herbarium collections for the species in this area, by applying flow cytometry for ploidy determination and by sequencing of two chloroplast markers. Results from our investigation suggest that the only population of the species in the Dinaric Alps is found in the Vranica Mts (Bosnia and Herzegovina). This population consists of diploid plants (unlike tetraploid populations from the Eastern Alps) that are slightly distinct genetically from those of the subspecies growing in the Eastern Alps and the Tatra Mts. Both the ploidy and their genetic distinction indicate that Vranica Mts most probably served as a refugium for the species during the Pleistocene glaciations. Considering its isolated geographical range and its genetic distinction, the population of L. alpina growing in the Vranica Mts should be considered as a separate subspecies.

Insights from Experiences on Antiplatelet Drugs in Stroke Prevention: A Review.

Reduction of hazard risk of cerebral ischemic event (stroke, transient ischemic attack (TIA)) represents the hard point to be achieved from primary or secondary preventive strategy in the best clinical practice. However, results from clinical trials, recommendations, guidelines, systematic review, expert opinions, and meta-analysis debated on the optimal pharmacotherapy to achieve the objective. Aspirin and a number of antiplatelet agents, alone or in combination, have been considered from large trials focused on stroke prevention. The present review summarizes, discusses results from trials, and focuses on the benefits or disadvantages originating from antiplatelet drugs. Sections of the review were organized to show both benefits or consequences from antiplatelet pharmacotherapy. Conclusively, this review provides a potential synopsis on the most appropriate therapeutic approach for stroke prevention in clinical practice.

Phylogenomics unravels Quaternary vicariance and allopatric speciation patterns in temperate-montane plant species: A case study on the Ranunculus auricomus species complex.

The time frame and geographical patterns of diversification processes in European temperate-montane herbs are still not well understood. We used the sexual species of the Ranunculus auricomus complex as a model system to understand how vicariance versus dispersal processes in the context of Pleistocene climatic fluctuations have triggered speciation in temperate-montane plant species. We used target enrichment sequence data from about 600 nuclear genes and coalescent-based species tree inference methods to resolve phylogenetic relationships among the sexual taxa of the complex. We estimated absolute divergence times and, using ancestral range reconstruction, we tested if speciation was enhanced by vicariance or by dispersal processes. Phylogenetic relationships among taxa were fully resolved with some incongruence in the position of the tetraploid R. marsicus. Speciation events took place in a very short time at the end of the Mid-Pleistocene Transition (830-580 thousand years ago [ka]). A second wave of intraspecific geographical differentiation occurred at the end of the Riss glaciation or during the Eemian interglacial between 200 and 100 ka. Ancestral range reconstruction suggests a widespread European ancestor of the R. auricomus complex. Vicariance has triggered allopatric speciation in temperate-montane plant species during the climatic deterioration that occurred during the last phase of the Mid-Pleistocene Transition. Vegetation restructuring from forest into tundra could have confined these forest species into isolated glacial macro- and microrefugia. During subsequent warming periods, range expansions of these species could have been hampered by apomictic derivatives and by other congeneric competitors in the same habitat.

Breeding system of diploid sexuals within the Ranunculus auricomus complex and its role in a geographical parthenogenesis scenario.

The larger distribution area of asexuals compared with their sexual relatives in geographical parthenogenesis (GP) scenarios has been widely attributed to the advantages of uniparental reproduction and polyploidy. However, potential disadvantages of sexuals due to their breeding system have received little attention so far. Here, we study the breeding system of five narrowly distributed sexual lineages of Ranunculus notabilis s.l. (R. auricomus complex) and its effects on outcrossing, inbreeding, female fitness, and heterozygosity. We performed selfing and intra- and interlineage crossings by bagging 481 flowers (59 garden individuals) followed by germination experiments. We compared seed set and germination rates, and related them to genetic distance and genome-wide heterozygosity (thousands of RADseq loci). Selfings (2.5%) unveiled a significantly lower seed set compared with intra- (69.0%) and interlineage crossings (69.5%). Seed set of intra- (65%) compared to interpopulation crossings (78%) was significantly lower. In contrast, all treatments showed comparable germination rates (32%-43%). Generalized linear regressions between seed set and genetic distance revealed positive relationships in general and between lineages, and a negative one within lineages. Seed set was the main decisive factor for female fitness. Germination rates were not related to genetic distance at any level, but were positively associated with heterozygosity in interlineage crossings. Experiments confirmed full crossability and predominant outcrossing among sexual R. notabilis s.l. lineages. However, up to 5% (outliers 15%-31%) of seeds were formed by selfing, probably due to semi-self-compatibility in a multi-locus gametophytic SI system. Less seed set in intrapopulation crossings, and higher seed set and germination rates from crossings of genetically more distant and heterozygous lineages (interlineage) indicate negative inbreeding and positive outbreeding effects. In GP scenarios, sexual species with small and/or isolated populations can suffer from decreased female fitness due to their breeding system. This factor, among others, probably limits range expansion of sexuals.

Desert-like badlands and surrounding (semi-)dry grasslands of Central Germany promote small-scale phenotypic and genetic differentiation in Thymus praecox.

Environmental heterogeneity among sites can generate phenotypic and genetic variation facilitating differentiation and microevolution of plant populations. Badlands are desert-like, predominantly vegetation-poor habitats often embedded in (semi-)dry grasslands. The desert-like conditions of badlands demand extreme adaptation of plants, that is, phenotypic modifications in short-term and/or natural adaptation in long-term. However, detailed knowledge is missing about both plant phenotypic and genetic differentiation in this unique and widely occurring habitat type. The present study focused on the largest known badlands systems in Central Europe located in the "Drei Gleichen" region, a designated nature conservation area in Central Germany. Locations were suitable for this study in terms of having co-occurring badlands and (semi-)dry grassland habitats (sites) occupied by the pioneer plant Thymus praecox. Here, we studied the environmental preferences, morphological and functional trait variation, and genetic variation using microsatellite markers of T. praecox. Results revealed significant, mainly site-dependent environmental, phenotypic, and genetic differentiation. In general, individuals in badlands are shorter in height and have lower patch sizes (length × width), relative growth rates, and smaller stomata. The PCA additionally unveiled slightly increased leaf robustness, trichome density, decreased stomatal conductance, fewer females, and earlier phenology in badlands. We interpret differentiation patterns as adaptive responses to light, temperature, drought, and nutrient stress conditions supported by reviewed literature. Genetic differentiation was strongest between local badlands and grassland sites, and clearly weaker among locations and between sites (in total) as indicated by G ST, AMOVA, PCoA, and population structure. Our study supports the importance of small-scale microhabitat conditions as a driver of microevolutionary processes, and the population's need for sufficient phenotypic variation and genetic resources to deal with environmental changes. We demonstrated that badlands are an appropriate model system for testing plant response to extreme habitats and that more research is needed on these fascinating landscapes.

Ragweeds and relatives: Molecular phylogenetics of Ambrosiinae (Asteraceae).

Ambrosiinae are one of the most distinct subtribes in the Heliantheae alliance (Asteraceae), mainly due to specialization toward wind pollination. Taxa of the subtribe are principally native to the Americas, although some species have attained a cosmopolitan distribution. Members of subtribe Engelmanniinae are considered close to Ambrosiinae, due to shared morphological traits. However, the placement of Ambrosiinae within the Heliantheae alliance has not yet been corroborated by phylogenetic analyses. In the present study, we test the circumscription of subtribe Ambrosiinae and examine relationships among its genera. We used sequence information from three plastid (psbA-trnH, trnQ-rps16 and trnL-F) and two nuclear (ITS and D35) marker regions. Phylogenetic inference analyses were conducted, applying Bayesian Inference (BI) and Maximum Likelihood (ML). Subtribe Ambrosiinae is found monophyletic or nearly so in all analyses. The genera Dugesia and Rojasianthe (previously considered part of subtribe Engelmanniinae) in some cases cluster together with Ambrosiinae; these genera are clearly not part of Engelmanniinae. Within Ambrosiinae, the genera Parthenium and Parthenice occupy basal positions, whereas members of the genus Ambrosia are the most derived representatives of the subtribe. Previous subdivision of Ambrosiinae into "Iveae" (members having androgynous capitula and free achenes) and "Ambrosieae" (genera with unisexual heads and achenes enclosed in burs) is not corroborated. Results also allow consideration of relationships among species and subgeneric groups within Parthenium, Iva, and Ambrosia.

How many names for a beloved genus? - Coalescent-based species delimitation in Xanthium L. (Ambrosiinae, Asteraceae).

The species category is the fundamental unit in biology. In the last decades, several studies have been carried out, using sequence information and phylogenies to resolve issues in taxonomically problematic groups. The multispecies coalescent theory, and the species-delimitation methods developed in the last years based on that, offer powerful and objective tools to determine species boundaries using sequence data. The genus Xanthium is a morphologically variable complex with several local forms, nowadays become cosmopolitan due to human-mediated dispersal. Past taxonomic treatments of the genus were based essentially on the burr morphology. They varied considerably in number of recognized species, depending on the importance that the different authors gave to burr traits such as burr size, pubescence, number and length of spines in the burrs, and the degree to which those are hooked. We used sequence information from two plastid regions (the intergenic spacer regions psbA-trnH and trnQ-rps16) and two nuclear ones (ITS1-5.8 S-ITS2 rDNA, and the single-copy nuclear marker D35). Two of the most advanced coalescent-based species delimitation methods (BP&P and STACEY) were applied, in order to objectively determine species boundaries in Xanthium. Results from the species-delimitation methods strongly support scenarios with a reduced number of species. Prior on the effective population size parameter (θ) had a strong influence on BP&P results. Analyses with large and small θ prior supported species delimitation scenarios with four and five species, respectively. STACEY recognized five cluster in the dataset, all supported by high posterior probability values. Five species are identified in Xanthium, in a great extent corresponding to the infrageneric classification given for the genus in past taxonomic revisions.

Phylogenetic Analysis and Molecular Characterization of Xanthium sibiricum Using DNA Barcoding, PCR-RFLP, and Specific Primers.

The fruits of Xanthium sibiricum have been widely used in traditional Chinese medicine for the treatment of nasal sinusitis and headaches. The genus Xanthium (cocklebur) is a taxonomically complex genus. Different taxonomic concepts have been proposed, some including several species, others lumping the different taxa in a few extremely polymorphic species. Due to the morphological similarities between species, the correct authentication of X. sibiricum is very difficult. Therefore, we established a polymerase chain reaction-restriction fragment length polymorphism method and diagnostic PCR based on nuclear internal transcribed spacer and chloroplast trnQ-rps16 barcodes to differentiate X. sibirium from related species.Results from the phylogenetic analyses based on sequence information from four marker regions (plastidal psbA-trnH and trnQ-rps16 and nuclear ITS and D35) support those taxonomic concepts accepting a reduced number of species, as four to five major clades are revealed in the phylogenetic reconstructions. X. sibiricum, together with some accessions from closely related taxa, is always supported as monophyletic, constituting a well-defined genetic entity. Allele-specific primer pairs for ITS and trnQ-rps16 were designed to amplify diagnostic products from the genomic DNA of X. sibiricum. Specific PCR in combination with digestion using the restriction enzyme MseI allowed for the identification of X. sibiricum by producing specific restriction patterns. The results demonstrate that the applied techniques provide effective and accurate authentication of X. sibiricum.

Mean Transaortic Gradient is an Emerging Predictor of Chronic Kidney Disease in Elderly Patients.

Arterial hypertension (AH) is a major risk factor for chronic kidney disease (CKD). However, whether AH maintains this role in the development of CKD in elderly patients with aortic stenosis (AS) or whether transaortic gradient influences CKD remains unclear. Consecutive hospitalized patients were prospectively recruited to evaluate the relationship between AS and CKD. In all patients, transthoracic 2-dimensional echocardiography was performed to evaluate AS; renal function was evaluated using the Chronic Kidney Disease Epidemiology Collaboration formula. A total of 346 patients were included in the study (mean age: 79.5 ± 7.4 years): 104 had diabetes mellitus (DM), 298 had AH, and 59 (moderate: 52; severe: 7) showed AS. After multivariate analysis, age ( P <.01), DM ( P = .02), and mean transaortic gradient ( P = .03), but not AH, were independent predictors of CKD. Both in the presence (n = 59) or absence (n = 287) of AS, the estimated glomerular filtration rate did not differ in patients with (51 ± 24 mL/min/1.73 m2 and 59 ± 25 mL/min/1.73 m2, respectively) and those without AH (50 ± 21 mL/min/1.73 m2 and 65 ± 24 mL/min/1.73 m2, respectively). In the whole population, for each mm Hg of mean transaortic gradient, the risk of CKD increased by 2.5 times.

Percutaneous Coronary Revascularization for Chronic Total Occlusions: A Novel Predictive Score of Technical Failure Using Advanced Technologies.

OBJECTIVES: The aims of this study were to describe the 10-year experience of a single operator dedicated to chronic total occlusion (CTO) and to establish a model for predicting technical failure. BACKGROUND: During the last decade, the interest in percutaneous coronary interventions (PCIs) of chronic total occlusions (CTOs) has increased, allowing the improvement of success rate. METHODS: One thousand nineteen patients with CTO underwent 1,073 CTO procedures performed by a single CTO-dedicated operator. The study population was subdivided into 2 groups by time period: period 1 (January 2005 to December 2009, n = 378) and period 2 (January 2010 to December 2014, n = 641). Observations were randomly assigned to a derivation set and a validation set (in a 2:1 ratio). A prediction score was established by assigning points for each independent predictor of technical failure in the derivation set according to the beta coefficient and summing all points accrued. RESULTS: Lesions attempted in period 2 were more complex in comparison with those in period 1. Compared with period 1, both technical and clinical success rates significantly improved (from 87.8% to 94.4% [p = 0.001] and from 77.6% to 89.9% [p < 0.001], respectively). A prediction score for technical failure including age ≥75 years (1 point), ostial location (1 point), and collateral filling Rentrop grade <2 (2 points) was established, stratifying procedures into 4 difficulty groups: easy (0), intermediate (1), difficult (2), and very difficult (3 or 4), with decreasing technical success rates. In derivation and validation sets, areas under the curve were comparable (0.728 and 0.772, respectively). CONCLUSIONS: With growing expertise, the success rate has increased despite increasing complexity of attempted lesions. The established model predicted the probability of technical failure and thus might be applied to grading the difficulty of CTO procedures.