Impact of Changes in Rectus Femoris Cross-Sectional Area Measured by Ultrasound on the Prognosis of Patients With Acute Heart Failure.

BACKGROUND: Low muscle mass in patients with acute heart failure (AHF) is associated with poor prognosis; however, this is based on a single baseline measurement, with little information on changes in muscle mass during hospitalization and their clinical implications. This study investigated the relationship between changes in rectus femoris cross-sectional area (RFCSA) on ultrasound and the prognosis of patients with AHF.Methods and Results: This is a retrospective evaluation of 284 AHF patients (mean [±SD] age 79.1±11.9 years; 116 female). RFCSA assessments at admission (pre-RFCSA), ∆RFCSA (i.e., the percentage change in RFCSA from admission to 2 weeks), and composite prognosis (all-cause death and heart failure-related readmission) within 1 year were determined. Patients were divided into 4 groups according to their median pre-RFCSA and ∆RFCSA after sex stratification: Group A, higher pre-RFCSA/better ∆RFCSA; Group B, higher pre-RFCSA/worse ∆RFCSA; Group C, lower pre-RFCSA/better ∆RFCSA; Group D, lower pre-RFCSA/worse ∆RFCSA. In the Cox regression analysis, with Group A as the reference, the cumulative event rate of Group C (hazard ratio [HR] 3.39; 95% confidence interval [CI] 0.71-16.09; P=0.124) did not differ significantly; however, the cumulative event rates of Group B (HR 7.93; 95% CI 1.99-31.60; P=0.003) and Group D (HR 9.24; 95% CI 2.57-33.26; P<0.001) were significantly higher. CONCLUSIONS: ∆RFCSA during hospitalization is useful for risk assessment of prognosis in patients with AHF.

Impact of sarcopenia and malnutrition on swallowing function utilizing ultrasonography in patients with acute heart failure: A retrospective cohort study.

BACKGROUND & AIMS: This study aimed to determine the impact of sarcopenia and nutritional risk on swallowing-related muscles by ultrasonography and dysphagia occurrence in older patients with acute heart failure (AHF) during hospitalization. METHODS: Patients with AHF aged ≥65 years without dysphagia (Food Intake LEVEL Scale [FILS] score ≥9) before admission were classified into four groups at admission: robust group, sarcopenia group (Asian Working Group for Sarcopenia 2019), nutritional risk group (geriatric nutritional risk index <92), and complicated group (with both sarcopenia and nutritional risk). Swallowing function (maximal hyoid displacement, geniohyoid muscle area and brightness, and maximal tongue pressure) and FILS were investigated from the medical records. RESULTS: In total, 131 patients with AHF (mean age 82.8 ± 7.1 years, 71 males) were enrolled during the study period; 33, 58, 5, and 35 were classified into the robust, sarcopenia, nutritional risk, and complicated groups, respectively. In the covariance analysis adjusted for age, sex, comorbidities, and cardiac function, the complicated group had significantly worse swallowing function than the sarcopenia and robust groups (P < 0.05). In the Cox proportional hazards model, in which event occurrence was defined as the first-time FILS score of ≥9 obtained during hospitalization, the sarcopenia group (hazard ratio [HR]: 0.83, 95 % confidence interval [CI]: 0.51-1.34, P = 0.438) and nutritional risk group (HR: 0.77, 95 % CI:0.25-2.32, P = 0.637) were not significantly different, but the complicated group (HR: 0.54, 95 % CI: 0.31-0.95, P = 0.033) had significantly lower cumulative event rates with the robust group as the reference. CONCLUSION: Sarcopenia and nutritional risk in older patients with AHF are risk factors for decreased swallowing function.

De novo genome assembly of the partial homozygous dihaploid potato identified PVY resistance gene (Rychc) derived from Solanum chacoense.

The isolation of disease resistance genes introduced from wild or related cultivated species is essential for understanding their mechanisms, spectrum and risk of breakdown. To identify target genes not included in reference genomes, genomic sequences with the target locus must be reconstructed. However, de novo assembly approaches of the entire genome, such as those used for constructing reference genomes, are complicated in higher plants. Moreover, in the autotetraploid potato, the heterozygous regions and repetitive structures located around disease resistance gene clusters fragment the genomes into short contigs, making it challenging to identify resistance genes. In this study, we report that a de novo assembly approach of a target gene-specific homozygous dihaploid developed through haploid induction was suitable for gene isolation in potatoes using the potato virus Y resistance gene Rychc as a model. The assembled contig containing Rychc-linked markers was 3.3 Mb in length and could be joined with gene location information from the fine mapping analysis. Rychc was successfully identified in a repeated island located on the distal end of the long arm of chromosome 9 as a Toll/interleukin-1 receptor-nucleotide-binding site-leucine rich repeat (TIR-NBS-LRR) type resistance gene. This approach will be practical for other gene isolation projects in potatoes.

Effect of Electrical Muscle Stimulation on the Reduction of Muscle Volume Loss in Acute Heart Failure Patients.

Electrical muscle stimulation (EMS) is expected to be considered as an add-on therapy for the usual rehabilitation of patients with chronic heart failure (HF). However, it remains unclear whether EMS can reduce muscle volume loss in patients with acute HF (AHF) immediately after hospitalization. Therefore, the aim of this study was to investigate if EMS could reduce the lower-limb muscle volume loss in patients with AHF. In this single-center, retrospective, observational study, lower-limb skeletal muscle volume, quadriceps muscle layer thickness, and clinical events (worsening HF or kidney function) were evaluated in 45 patients with AHF (mean age, 77.4 ± 11.6 years, 31 males). All patients underwent EMS on the right leg, in addition to usual rehabilitation, for 20 minutes per day, 5 days per week, for 2 weeks. A two-factor (time × leg) analysis of variance was performed to compare the difference between the right leg (usual rehabilitation and EMS) and left leg (usual rehabilitation only). The skeletal muscle mass decreased by 11.6% ± 19.7% from baseline in the right leg and by 20.4% ± 16.1% in the left leg (interaction; F = 4.54, P = 0.036). The quadriceps muscle layer thickness decreased by 10.2% ± 7.1% from baseline in the right leg and by 13.5% ± 6.0% in the left leg (interaction; F = 10.50, P = 0.002). No clinical events were related to EMS. Results showed that EMS combined with usual rehabilitation for patients with AHF has the potential to inhibit muscle volume loss.

Improvement of diagnostic markers for resistance to Globodera pallida and application for selection of resistant germplasms in potato breeding.

Occurrence of pale potato cyst nematode, Globodera pallida (Stone) Behrens, was first recorded in Japan in 2015. Among several control measures, cultivation of resistant potato (Solanum tuberosum L.) varieties is the most effective in cost and environmental impact. As no G. pallida-resistant varieties have yet been developed in Japan, great emphasis is being placed on screening of germplasm possessing the resistance and development of the resistant varieties. In this study, we first improved previously reported DNA markers linked to the G. pallida resistance loci (GpaIVs adg and Gpa5) and then used these to screen more than 1,000 germplasms to select several candidate germplasms with resistance. We performed inoculation testing on the selected candidates and identified several resistant germplasms to the Japanese G. pallida population. Furthermore, we developed a simultaneous detection method combining three DNA markers linked to G. pallida and Globodera rostochiensis (Wollenweber) Behrens resistance loci. We validated the ability of C237-I marker to select resistant allele of GpaIVs adg and predict the presence of resistance in a Japanese breeding population. Resistant germplasms identified in this study could potentially be used to develop G. pallida-resistant varieties. The marker evaluation methods developed in this study will contribute to the efficient development of resistant varieties.

Polyploid QTL-seq towards rapid development of tightly linked DNA markers for potato and sweetpotato breeding through whole-genome resequencing.

Potato (Solanum tuberosum L.) and sweetpotato (Ipomoea batatas L.), which are nutritionally and commercially important tuberous crops, possess a perplexing heredity because of their autopolyploid genomes. To reduce cross-breeding efforts for selecting superior cultivars from progenies with innumerable combinations of traits, DNA markers tightly linked to agronomical traits are required. To develop DNA markers, we developed a method for quantitative trait loci (QTL) mapping using whole-genome next-generation sequencing (NGS) in autopolyploid crops. To apply the NGS-based bulked segregant method, QTL-seq was modified. (1) Single parent-specific simplex (unique for one homologous chromosome) single-nucleotide polymorphisms (SNPs), which present a simple segregation ratio in the progenies, were exploited by filtering SNPs by SNP index (allele frequency). (2) Clusters of SNPs, which were inherited unevenly between bulked progenies with opposite phenotypes, especially those with an SNP index of 0 for the bulk that did not display the phenotypes of interest, were explored. These modifications allowed for separate tracking of alleles located on each of the multiple homologous chromosomes. By applying this method, clusters of SNPs linked to the potato cyst nematode resistance H1 gene and storage root anthocyanin (AN) content were identified in tetraploid potato and hexaploid sweetpotato, respectively, and completely linked DNA markers were developed at the site of the presented SNPs. Thus, polyploid QTL-seq is a versatile method that is free from specialized manipulation for sequencing and construction of elaborate linkage maps and facilitates rapid development of tightly linked DNA markers in autopolyploid crops, such as potato and sweetpotato.

Discontinuation of Cardiac Resynchronization Therapy for Heart Failure Due to Dilated Cardiomyopathy in a 61-Year-Old Female "-Super-Responder" with Return of a Reduced Left Ventricular Ejection Fraction to Normal.

BACKGROUND Although cardiac resynchronization therapy (CRT) is widely used, it has been validated only during active pacing. "Super-responders" are patients with normalized or markedly improved left ventricular (LV) systolic function with CRT who may experience a decline in cardiac function with CRT discontinuation. CASE REPORT A 61-year-old woman with a nonischemic cardiomyopathy was admitted to our hospital in September 2008 for the treatment of heart failure (HF). Cardiac assessment revealed impaired LV function with an ejection fraction of 18%, LV dilatation, and left bundle branch block (LBBB). Despite optimized medical treatment, her HF progressed, with a rapid increase in LV chamber size, mitral regurgitation, and widening of the QRS complex. In July 2011, the patient initially refused CRT, but later consented to the procedure; CRT pacemaker implantation was subsequently performed. Thereafter, the LVEF improved from 27% to 46%, LV diastolic dimension decreased rapidly from 79 mm to 56 mm, and LVEF (65%) and LV size (47 mm) normalized within 1 year later. As of August 2012, battery exchange was needed within 1 year because of high LV pacing thresholds. In October 2012, although CRT discontinuation was not recommended, we discontinued CRT to conserve battery life with the patient's consent, hoping to maintain her condition with pharmaceutical treatment. She remained stable through January 2020, with no indication of re-exacerbation. CONCLUSIONS We describe a female patient with a nonischemic cardiomyopathy and LBBB who demonstrated a super-response to CRT and maintained improvement in LV function and functional status for 8 years after discontinuing CRT.

Breeding of a new potato variety 'Nagasaki Kogane' with high eating quality, high carotenoid content, and resistance to diseases and pests.

'Nagasaki Kogane' is a new potato variety bred from a cross between 'Saikai 35' as a female parent and 'Saikai 33' as a male. 'Saikai 35' is resistant to bacterial wilt, contains the H1 and Rychc genes for resistance to the potato cyst nematode (PCN) and potato virus Y (PVY), respectively, and has high carotenoid content, while 'Saikai 33' has large and high-yielding tubers and is resistant to both bacterial wilt and PCN. The carotenoid content of 'Nagasaki Kogane' is higher than that of 'Dejima', a common double cropping variety. The taste quality of steamed 'Nagasaki Kogane' is comparable to that of 'Inca-no-mezame' tubers, which has high levels of carotenoid, and superior to 'Nishiyutaka', another popular double cropping variety. 'Nagasaki Kogane' is suitable for French fries, because its tuber has high starch content. The marketable yield of 'Nagasaki Kogane' was higher than that of 'Inca-no-mezame' in spring cropping, although it was lower than that of 'Nishiyutaka' in double cropping regions. 'Nagasaki Kogane' tubers are larger on average than 'Inca-no-mezame' tubers in spring cropping. Moreover, the 'Nagasaki Kogane' variety is resistant to PCN and PVY, and exhibits a high level of resistance to bacterial wilt.

Inheritance of low pasting temperature in sweetpotato starch and the dosage effect of wild-type alleles.

Sweetpotato (Ipomoea batatas (L.) Lam.), which is an outcrossing hexaploid, is one of the most important starch-producing crops in the world. During the last decade, new sweetpotato cultivars, e.g. 'Quick Sweet', which have approximately 20°C lower pasting temperature, slower retrogradation and higher digestibility of raw starch than ordinary cultivars, have been developed in Japan. Genetic analysis of these variants with low pasting temperature starch was conducted in this study. Using 8 variants and 15 normal clones, 26 families were generated. The results from analyzing these progenies suggested that this trait is a qualitative character controlled by one recessive allele (designated spt), which is inherited in a hexasomic manner. A dosage effect of the wild-type Spt allele was found for starch pasting temperature, although the effect was not linear. These results will aid breeders to develop sweetpotato cultivars with a range of starch pasting temperatures.

The Efficacy and Safety of Antegrade Inoue-Balloon Aortic Valvuloplasty to Treat Calcific Critical Aortic Stenosis.

BACKGROUND: Critical aortic stenosis (AS) with severe calcific degeneration often resists conventional retrograde percutaneous balloon aortic valvuloplasty (PBAV). To enhance therapeutic efficacy, a novel PBAV technique has been developed by utilizing a single Inoue balloon via an antegrade approach, performing multiple inflations with step-up increases (M-PBAV) of balloon diameter to the size of the surgical valve ring. PATIENTS AND METHODS: A total of 405 non-surgical patients with critical AS were treated by M-PBAV and the acute therapeutic response and long-term clinical course were evaluated; some patients underwent the procedure on two or three occasions. RESULTS: In a total of 456 procedures, mean transaortic valve pressure gradient improved from an initial 63.6 ± 17.3 mm Hg to 22.7 ± 8.9 mm Hg post PBAV (P<.01). Mean aortic valve area increased from an initial 0.55 ± 0.15 cm² to 0.98 ± 0.20 cm² immediately after M-PBAV (P<.01). Clinical symptoms (New York Heart Association [NYHA] class) improved over time. Prior to M-PBAV, baseline NYHA class I-II was 9.1%, and NYHA class III-IV was 90.9%. At 12 months post M-PBAV, mortality was 17.1%, with repeat M-PBAV plus surgical AVR at 12.7%, 10.5% NYHA class III-IV, and 59.6% NYHA class I-II. At 24 months post M-PBAV, mortality was 25.8%, with repeat PBAV plus surgical AVR at 19.0%, 8.8% NYHA class III-IV, and 46.2% NYHA class I-II. Adverse events related to the procedure included critical AR (0.5%), cardiac tamponade (1.8%), intraprocedure hemodynamic compromise requiring percutaneous cardiopulmonary support (0.5%), and reversible cerebral ischemia (1.3%). No myocardial infarct or vascular complications occurred. CONCLUSION: M-PBAV enhanced the therapeutic efficacy and procedural safety of valvuloplasty to treat severely calcified critical AS, and diversified its clinical roles.

Challenges of breeding potato cultivars to grow in various environments and to meet different demands.

The potato (Solanum tuberosum L.) is cultivated all year round in Japan by using four types of cropping: summer and winter croppings, and double cropping in spring and fall. In each cropping season, growth conditions such as temperature, day length, and growing period, differ drastically; thus, different cultivars adapted to each environment are required. Breeding stations are located in both summer cropping areas and double cropping areas, and cultivars suitable for each cropping system are developed. The required cultivars differ according to cropping type and according to use such as table use, food processing, and starch production. The qualities necessary for each purpose differ and are therefore evaluated accordingly. Improvements in pest and disease resistance and in yield abilities are important as common breeding targets for all purposes. To develop potato cultivars that meet different needs, breeders have continued efforts to improve these traits. In this review, we introduce our approaches to developing new potato cultivars. We also discuss problems predicted in the future and introduce our efforts on broadening genetic diversity.

DNA marker-assisted evaluation of potato genotypes for potential resistance to potato cyst nematode pathotypes not yet invading into Japan.

One of major objectives of crop breeding is conferring resistance to diseases and pests. However, large-scale phenotypic evaluation for many diseases and pests is difficult because strict controls are required to prevent their spread. Detection of disease resistance genes by using DNA markers may be an alternative approach to select potentially resistant accessions. Potato (Solanum tuberosum L.) breeders in Japan extensively use resistance gene H1, which confers nearly absolute resistance to potato cyst nematode (Globodera rostochiensis) pathotype Ro1, the only pathotype found in Japan. However, considering the possibility of accidental introduction of the other pathotypes, breeding of resistant varieties is an important strategy to prevent infestation by non-invading pathotypes in Japan. In this study, to evaluate the prevalence of resistance genes in Japanese genetic resources, we developed a multiplex PCR method that simultaneously detects 3 resistance genes, H1, Gpa2 and Gro1-4. We revealed that many Japanese varieties possess not only H1 but Gpa2, which are potentially resistant to other pathotypes of potato cyst nematode. On the other hand, no genotype was found to have the Gro1-4, indicating importance of introduction of varieties having Gro1-4. Our results demonstrate the applicability of DNA-marker assisted evaluation of resistant potato genotypes without phenotypic evaluation.

An improved CARV process for bioethanol production from a mixture of sugar beet mash and potato mash.

A mixed mash of sugar beet roots and potato tubers with a sugar concentration of 23.7% w/v was used as a feedstock for bioethanol production. Enzymatic digestion successfully reduced the viscosity of the mixture, enabling subsequent heat pretreatment for liquefaction/sterilization. An energy-consuming thick juice preparation from sugar beet for concentration and sterilization was omitted in this new process.

Intravascular ultrasound-guided percutaneous coronary interventions with minimum contrast volume for prevention of the radiocontrast-induced nephropathy: report of two cases.

Radiocontrast-induced nephropathy (CIN) is one of the most serious complications of percutaneous coronary interventions (PCI). The prevention of PCI-related CIN for chronic kidney disease (CKD) patients has not been established yet. The intravascular ultrasound (IVUS) is commonly used as an imaging device during PCI. We performed IVUS-guided PCI while only using fluoroscopic imaging and without administering any routine contrast dye injection during the procedures. All patients underwent a baseline coronary angiography prior to the elective PCI. During the PCI, all the following procedures were done with X-ray fluoroscopic imaging without or with a minimized contrast dye injection: the engagement of the guiding catheter, insertion of the coronary guidewire, insertion of the IVUS catheter, the stent deployment and the post-dilatation. The diameter and the length of the balloon and the stent were determined according to the pre-procedural IVUS findings, and the end point of the stent dilatation was also judged according to the acquired minimal cross-sectional area of the stent. Here we report our findings from two cases representative of IVUS-guided minimum contrast PCI in which the volumes of contrast dye during the procedure were 5 and 4 ml, respectively. No CIN occurred after either procedure. The IVUS-guided minimum contrast PCI could be a promising option for the prevention of CIN after PCI.

Potential difficulty for accurate categorization of drug-eluting stent thrombosis without coronary angiography: unignorable involvement of the cases with new onset acute myocardial infarction occurred in target vessels.

Very late stent thrombosis (VLST) is a major unresolved problem of drug-eluting stent (DES) implants. However, its actual incidence with respect to the distribution of DES-target vessel and accuracy of adjudicating stent thrombosis according to the ARC definition has not been yet adequately evaluated. We studied 720 patients who had completed over 1 year from elective DES implantation. In this cohort, we extracted patients who present acute coronary syndrome (ACS) (n = 3, 0.4%). The timing of ACS events was 17, 19, and 24 months after DES implantation. At the time of presentation, VLST was strongly suspected as the initial diagnosis, however, coronary angiography (CAG) confirmed the different culprit lesion from DES and clearly no thrombus within the DES. According to ARC definition, three probable stent thromboses in this cohort before CAG, however, no stent thrombosis was confirmed after the CAG. Thus, no stent thrombosis was confirmed among this study population. In the very late phase after DES implantation, new onset ACS is not at all extraordinary occurrence in the target vessels of previous DES implantation. However, stent thrombosis is often assumed without angiographic confirmation. The clinical possibility that non-stent thrombosis is incidentally diagnosed with stent thrombosis without angiographic confirmation should be considered within the current accepted definition of stent thrombosis.

Angiographic evaluation of right upper-limb arterial anomalies: implications for transradial coronary interventions.

OBJECTIVES: Upper-limb arterial anomalies are sometimes encountered during transradial coronary procedures. These anomalies may contribute to procedural failure or to vascular complications, and are a major reason why many operators tend to avoid transradial procedures. We investigated the frequency of right upperlimb arterial anomalies using antegrade arteriography in patients undergoing transbrachial coronary angiography or intervention, and discuss the potential impact of these anomalies on the transradial procedure. METHODS: We prospectively studied 163 consecutive patients who underwent right transbrachial coronary angiography or intervention for the first time during the period from May 2007 to December 2007. Following the transbrachial procedure, we performed antegrade transbrachial arteriography of right upper-limb arteries in these patients and investigated the frequency and anatomy of arterial anomalies. RESULTS: A total of 40 upper-limb arterial anomalies were observed in 38 patients (23.3%). These included 8 abnormal origins (4.9%), 2 radio-ulnar loops (1.2%), 25 tortuosities (15.3%), 4 stenoses (2.5%) and 1 loop (0.6%). In patients with congenital lesions (8 patients; 4.9%), abnormal origin of the radial artery was the most common anomaly encountered, and in the acquired group (25 patients; 15.3%), tortuosity was the most common abnormality. CONCLUSION: Even with a 23.3% incidence of right upper-limb arterial abnormalities, 98.8% of patients were acceptable for transradial coronary intervention except for 1.2% of radio-ulnar loops.

Analysis of right radial artery for transradial catheterization by quantitative angiography--anatomical consideration of optimal radial puncture point.

OBJECTIVES: To determine the optimal radial puncture point, we analyzed the anatomy and luminal diameter of the right radial artery (RA) by quantitative angiography. BACKGROUND: Difficulty of radial puncture has impeded the establishment of the transradial approach as the standard procedure for cardiac catheterization. METHODS: Antegrade angiography was performed from the right brachial artery in 135 patients who underwent coronary angiography. Presence and location of a bifurcation in the area of the RA puncture were analyzed. Furthermore, inner luminal diameter of the RA was quantitatively measured. We used the line between the styloid process and the ulnar styloid process (R-U line) as an anatomical reference point. RESULTS: Radial arterial bifurcation with a superficial palmar branch was angiographically observed in 66 patients (48.9%). The inner luminal diameter was significantly larger at the proximal point to the point of bifurcation. The bifurcation level was located at a median of -3.33 mm (interquartile range: -5.60 to 4.69 mm) below the R-U line. Radial puncture at 10 mm proximal to the R-U line could avoid bifurcation in 91.9% of all cases. Mean radial, ulnar and brachial arterial inner diameters were 2.94 +/- 0.52 mm, 2.51 +/- 0.49 mm and 4.53 +/- 0.62 mm. The RA size within 10-60 mm above the R-U line was nearly invariable throughout the range. CONCLUSION The radial puncture level should be proximal to the radial bifurcation because of its lumen size. The ideal puncture point was found to be at least 10 mm proximal to the R-U line.

Selection of stress-tolerant yeasts for simultaneous saccharification and fermentation (SSF) of very high gravity (VHG) potato mash to ethanol.

Highly concentrated bioethanol production requires less volume in fermentation tanks and conserves distillery energy. We screened osmotolerant yeasts from a collection of 1699 yeast strains at our institute and found that three strains, NFRI3062, NFRI3213, and NFRI3225, were candidates for use in bioethanol production. All of these strains belonged to Saccharomyces cerevisiae. NFRI3062 produced 15.0% (w/v) of ethanol from YPD medium containing 35% glucose cultivated at 30 degrees C for 60 h, while S. cerevisiae NBRC0224, which has previously been reported suitable for ethanol production, only produced 13.0% (w/v). The thermotolerances of NFRI3213 and NFRI3225 were also superior to those of NBRC0224 and NFRI3062. We also demonstrated the simultaneous saccharification and fermentation (SSF) of very high gravity (VHG) potato mash and sweet-potato mash. NFRI3225 produced ethanol from potato mash at the fastest rate and in the highest volume (13.7% (w/v)) among the tested strains. The maximum productivity and ethanol yields were 9.1g/L/h and 92.3%, respectively. Although the potato mash was not sterilized, bacterial contamination was not observed. This may have been due to the growth inhibition of bacteria by the rapid glucose consumption and ethanol production of NFRI3225 during the VHG-SSF process.

Intravascular ultrasound criteria for determination of optimal longitudinal positioning of sirolimus-eluting stents.

BACKGROUND: Several studies have indicated that the clinical outcomes of sirolimus-eluting stents (SES) are significantly associated with longitudinal positioning of the stent relative to the underlying plaque distribution. METHODS AND RESULTS: Optimal SES landing was determined using unique stepwise intravascular ultrasound (IVUS) criteria, mainly targeting the sites with plaque burden <50% (plaque area/external elastic membrane area x100). To verify the criteria, (1) achievability and (2) actual impact on clinical and angiographic outcomes were assessed. A total of 162 consecutive patients with 180 lesions were enrolled and treated according to the IVUS criteria. Plaque burden at the proximal and distal margins was 41.4+/-13.6% (n=144) and 34.9+/-15.6% (n=170), respectively (within 3 mm of stent ends). The target was achieved in 72.3% of the proximal and 84.1% of the distal margin for the criteria. A strikingly low angiographic margin re-stenosis rate (2.7% of proximal and 1.4% of distal margin) and low target lesion revascularization rate (2.2%) were achieved. Receiver operator characteristic curve indicated that plaque burden was the strongest predictor of margin re-stenosis and its threshold (51.6%) was almost identical to that of the criteria. CONCLUSIONS: The proposed stepwise IVUS criteria mainly targeting plaque burden <50% are feasible and useful in the real-world practice of SES implantation.