Search

Abstract Intradialytic hypotension (IDH) is a common complication during hemodialysis that increases cardiovascular morbidity and mortality. Aortic stenosis (AS) is a cause of IDH. Transcatheter aortic valve replacement (TAVR) has become an established treatment for patients with severe AS. However, whether TAVR reduce the frequency of IDH has not been investigated. This study aims to verify the efficacy of TAVR for reduction of the frequency of IDH. Consecutive hemodialysis patients who underwent TAVR at Sendai Kosei Hospital from February 2021 to November 2021 with available records 1 month before and 3 months after TAVR were included in the study. IDH was defined as a decrease in systolic blood pressure by 20 mmHg or a decrease in the mean blood pressure by 10 mmHg associated with hypotensive symptoms or requiring intervention. Patients with ≥ 3 episodes of IDH in ten hemodialysis sessions comprised the IDH group. Overall, 18/41 (43.9%) patients were classified into the IDH group. In ten hemodialysis sessions, IDH events were observed 2.1, 4.3, and 0.4 times in the overall cohort, IDH group, and non-IDH group, respectively. After TAVR, the incidence of IDH decreased from 43.2 to 10.3% (p

Abstract In humans, uric acid is an end-product of purine metabolism. Urate excretion from the human kidney is tightly regulated by reabsorption and secretion. At least eleven genes have been identified as human renal urate transporters. However, it remains unclear whether all renal tubular cells express the same set of urate transporters. Here, we show renal tubular cells are divided into three distinct cell populations for urate handling. Analysis of healthy human kidneys at single-cell resolution revealed that not all tubular cells expressed the same set of urate transporters. Only 32% of tubular cells were related to both reabsorption and secretion, while the remaining tubular cells were related to either reabsorption or secretion at 5% and 63%, respectively. These results provide physiological insight into the molecular function of the transporters and renal urate handling on single-cell units. Our findings suggest that three different cell populations cooperate to regulate urate excretion from the human kidney, and our proposed framework is a step forward in broadening the view from the molecular to the cellular level of transport capacity.

Transporter research primarily relies on the canonical substrates of well-established transporters. This approach has limitations when studying transporters for the low-abundant micromolecules, such as micronutrients, and may not reveal physiological functions of the transporters. While d-serine, a trace enantiomer of serine in the circulation, was discovered as an emerging biomarker of kidney function, its transport mechanisms in the periphery remain unknown. Here, using a multi-hierarchical approach from body fluids to molecules, combining multi-omics, cell-free synthetic biochemistry, and ex vivo transport analyses, we have identified two types of renal d-serine transport systems. We revealed that the small amino acid transporter ASCT2 serves as a d-serine transporter previously uncharacterized in the kidney and discovered d-serine as a non-canonical substrate of the sodium-coupled monocarboxylate transporters (SMCTs). These two systems are physiologically complementary, but ASCT2 dominates the role in the pathological condition. Our findings not only shed light on renal d-serine transport, but also clarify the importance of non-canonical substrate transport. This study provides a framework for investigating multiple transport systems of various trace micromolecules under physiological conditions and in multifactorial diseases.

Background: Despite the encouragement of early initiation and titration of guideline-directed medical therapy (GDMT) for the treatment of heart failure (HF), most patients do not receive an adequate type and dose of pharmacotherapy in the real world. Objectives: This study aimed to determine the efficacy of titrating composite GDMT in patients with HF with reduced and mildly reduced ejection fraction and to identify patient conditions that may benefit from titration of GDMT. Methods: This was a two-center, retrospective study of consecutive patients hospitalized with acute decompensated heart failure (ADHF). Patients were classified into two groups according to a scoring scale determined by combination and doses of four types of HF agents (ACEis/ARBs/ARNis, BBs, MRAs, and SGLT2is) at discharge. A score of 5 or greater was defined as titrated GDMT, and a score of 4 or less was regarded as sub-optimal medical therapy (MT). Results: A total of 979 ADHF patients were screened. After 553 patients were excluded based on exclusion criteria, 426 patients (90 patients in the titrated GDMT group and 336 patients in the sub-optimal MT group) were enrolled for the analysis. The median follow-up period was 612 (453–798) days. Following statistical adjustment using the propensity score weighting method, the 2-year composite endpoint (composite of cardiac death and HF rehospitalization) rate was significantly lower in the titrated GDMT group, at 19%, compared with the sub-optimal MT group: 31% (score 3–4 points) and 43% (score 0–2 points). Subgroup analysis indicated a marked benefit of titrated GDMT in particular patient subgroups: age < 80 years, BMI 19.0–24.9, eGFR > 20 mL/min/1.73 m2, and serum potassium level ≤ 5.5 mmol/L. Conclusions: Prompt initiation and dose adjustment of multiple HF medications, with careful monitoring of the patient’s physiologic and laboratory values, is a prerequisite for improving the prognosis of patients with heart failure.

Background The balloon-expandable SAPIEN 3 (S3) is superior to the older-generation balloon-expandable SAPIEN XT (XT) in a lower incidence of paravalvular aortic regurgitation, lower complication rates and better survival in transcatheter aortic valve implantation (TAVI). However, prosthesis–patient mismatch (PPM) more frequently occurs in S3 than XT. Further, little information is available on PPM after TAVI using S3 in Asians. This study aims to determine the incidence and predictors of PPM in S3 by focusing on the difference between S3 and XT using data from a Japanese multicentre registry.Methods From the Optimised transCathEter vAlvular iNtervention-TAVI (OCEAN-TAVI) registry, 2134 patients undergoing TAVI using S3 or XT were included. PPM was defined as moderate if ≧0.65 but ≦0.85 cm2/m2 or severe if

Objectives Patients’ backgrounds and clinical outcomes in urgent/emergent/salvage transcatheter aortic valve replacement (Em-TAVR) remain unclear. We investigated patient characteristics and the mortality in Em-TAVR and the predictors for the need for Em-TAVR.Methods We consecutively enrolled 1613 patients undergoing TAVR for severe aortic stenosis between October 2013 and July 2016 from the Optimised transCathEter vAlvular interventioN (OCEAN)-transcatheter aortic valve implantation (TAVI) registry. The urgency was based on the European System for Cardiac Operative Risk Evaluation II. Urgent, emergent or salvage were included with the Em-TAVR group and elective with the El-TAVR group.Results Em-TAVR was observed in 87 (5.4%) patients. A higher Clinical Frailty Scale (CFS), peripheral artery disease (PAD), hypoalbuminaemia, reduced left ventricular ejection fraction (LVEF) and preoperative at least moderate mitral regurgitation (MR) predicted the need for the Em-TAVR by the multivariate logistic regression analysis. The Em-TAVR group had the higher Society of Thoracic Surgeons Score (13.7 (IQR 8.2–21.0) vs 6.5 (IQR 4.6–9.2); p