Early acute kidney injury after tacrolimus administration in heart transplant recipients receiving basiliximab induction therapy.

OBJECTIVE: In this study, we aimed to analyze the association among the timing of tacrolimus initiation, time required to reach the target blood concentration, and early acute kidney injury (AKI) after tacrolimus administration in heart transplant recipients who received basiliximab induction therapy. MATERIALS AND METHODS: 88 patients treated with tacrolimus-based immunosuppressive therapy were retrospectively reviewed. Induction therapy was administered to 52 patients. AKI was evaluated within 7 days of tacrolimus administration. RESULTS: The rate of increase in tacrolimus trough concentration to the target trough concentration of 10 µg/mL early after its administration was set to be similar in the basiliximab induction and non-induction group; 8 and 2 patients developed AKI in the induction and non-induction group, respectively. In the induction group, there was no significant difference in the timing of tacrolimus initiation and the time required to reach the target concentration between patients who developed and did not develop AKI. In contrast, the cumulative incidence of AKI was significantly different between patients with an estimated glomerular filtration rate below and those with an estimated glomerular filtration rate above 43 mL/min/1.73m2 at the start of tacrolimus administration (37.5% and 11.4%, respectively; p = 0.045). CONCLUSION: In patients receiving basiliximab induction therapy, the timing of tacrolimus initiation and the time to reach the target concentration are unlikely to be associated with early AKI after tacrolimus administration. However, the recovery of sufficient renal function after heart transplantation is important for determining the start time of tacrolimus.

Risk Assessment of Neutropenia during Low-Dose Valganciclovir Prophylaxis for Heart Transplant Recipients.

The aim of this study was to investigate whether low-dose valganciclovir (VGCV) prophylaxis for cytomegalovirus (CMV) infection increased the risk of developing neutropenia in heart transplant recipients (HTRs). Forty-three HTRs receiving VGCV were divided into two groups: those who received VGCV prophylaxis (n = 22) and those who did not (n = 21). Neutropenia was defined as an absolute neutrophil count ˂1500/µL and was monitored for approximately one year post-transplantation. In the prophylaxis group, 77.3% (17/22) of HTRs experienced neutropenia, which was significantly higher than that in the no prophylaxis group (42.9% [9/21], p = 0.031). No significant differences in the duration of VGCV administration and cumulative dose up to the first neutropenia episode were observed between the groups. Meanwhile, the cumulative dose of mycophenolate mofetil was significantly higher in the prophylaxis group than in the no prophylaxis group (p = 0.018); the daily maintenance dose and regularly measured area under the concentration-time curve (AUC) of mycophenolic acid did not significantly differ between groups. In conclusion, the risk of developing neutropenia was higher in HTRs receiving low-dose VGCV prophylaxis than it was in those not receiving prophylaxis, probably not attributed to dosing period and cumulative dose of VGCV until the onset of neutropenia.

Discontinuation of oral amphotericin B therapy does not influence the pharmacokinetics of tacrolimus in heart transplant patients.

OBJECTIVE: Amphotericin B (AMPH-B) is used to prevent opportunistic infections associated with immunosuppressive therapy after heart transplantation (HTx), while the blood concentrations of tacrolimus (TAC) are carefully controlled. Although AMPH-B has the potential to inhibit TAC metabolism in in vitro studies, its interaction with clinically used AMPH-B oral suspension has not been investigated. In the present study, we examined whether oral AMPH-B therapy influences the pharmacokinetics of TAC in HTx patients. MATERIALS AND METHODS: A retrospective study was performed at the National Cerebral and Cardiovascular Center in Japan. All patients with HTx enrolled in the study received standard triple-drug immunosuppression therapy including the regular release of TAC, mycophenolate mofetil, and prednisolone as well as prophylactic therapy with AMPH-B oral suspension. Patient characteristics and clinical laboratory data were collected from the electronic medical record system. Blood concentrations of TAC were used for pharmacokinetic analysis. RESULTS: A total of 14 patients were enrolled in the study. There were no statistically significant differences in the variables except for serum creatinine levels and eGFR before and after discontinuation of oral AMPH-B therapy. The dose and trough concentrations of TAC and the area under the time-concentration curve and apparent oral clearance calculated from its concentrations were not influenced by discontinuation of AMPH-B treatment. CONCLUSION: The prophylactic treatment with AMPH-B oral suspension did not influence the pharmacokinetics of TAC and was demonstrated as a safe and easy method to prevent early post-HTx fungal infection.

Relationship between serum bepridil concentration and corrected QT interval.

OBJECTIVE: Bepridil prolongs the QT interval and can induce torsade de pointes. Although increased bepridil concentration may be a primary cause of prolonged QT, the relationship between serum bepridil concentration and prolonged QT remains unclear. We investigated the relationship between serum bepridil concentration and the corrected QT (QTc) interval in patients treated with bepridil. MATERIALS AND METHODS: A retrospective study was performed at the National Cerebral and Cardiovascular Center in Japan. Patients with atrial fibrillation who were treated with bepridil from January 2014 to December 2015 were enrolled in the study. Serum bepridil concentrations and electrocardiogram data collected more than 21 days after the initiation of bepridil were used for analysis. RESULTS: A total of 60 patients were included in this study. There was a significant difference in mean QTc interval before and after initiation of bepridil (p < 0.0001). A significant relationship was observed between bepridil dose (p = 0.014) or serum bepridil concentration (p < 0.001) and QTc interval. Additionally, a significant relationship was observed between serum bepridil concentration and ΔQTc (p = 0.034). In the study, 4 patients developed QTc prolongation ≥ 500 ms after the initiation of bepridil. Serum bepridil concentration in this group was significantly higher compared with the group that did not display prolonged QTc (973 ± 651 vs. 526 ± 310 ng/mL, p = 0.01). CONCLUSION: This study revealed that the QTc interval was significantly associated with serum bepridil concentration. Serum bepridil concentration beyond a therapeutic range may be a critical risk factor for developing QTc prolongation.

Influence of Induction Therapy Using Basiliximab With Delayed Tacrolimus Administration in Heart Transplant Recipients　- Comparison With Standard Tacrolimus-Based Triple Immunosuppression.

BACKGROUND: Appropriate indications and protocols for induction therapy using basiliximab have not been fully established in heart transplant (HTx) recipients. This study elucidated the influence of induction therapy using basiliximab along with delayed tacrolimus (Tac) initiation on the outcomes of high-risk HTx recipients.Methods and Results:A total of 86 HTx recipients treated with Tac-based immunosuppression were retrospectively reviewed. Induction therapy was administered to 46 recipients (53.5%) with impaired renal function, pre-transplant sensitization, and recipient- and donor-related risk factors (Induction group). Tac administration was delayed in the Induction group. Induction group subjects showed a lower cumulative incidence of acute cellular rejection grade ≥1R after propensity score adjustment, but this was not significantly different (hazard ratio [HR]: 0.63, 95% confidence interval [CI]: 0.37-1.08, P=0.093). Renal dysfunction in the Induction group significantly improved 6 months post-transplantation (P=0.029). The cumulative incidence of bacterial or fungal infections was significantly higher in the Induction group (HR: 10.6, 95% CI: 1.28-88.2, P=0.029). CONCLUSIONS: These results suggest that basiliximab-based induction therapy with delayed Tac initiation may suppress mild acute cellular rejection and improve renal function in recipients with renal dysfunction, resulting in its non-inferior outcome, even in high-risk patients, when applied to the appropriate recipients. However, it should be carefully considered in recipients at a high risk of bacterial and fungal infections.

Drug interactions between tacrolimus and clotrimazole troche: a data mining approach followed by a pharmacokinetic study.

PURPOSE: This study investigated the effects of clotrimazole troche on the risk of transplant rejection and the pharmacokinetics of tacrolimus. METHODS: The data mining approach was used to investigate whether the use of clotrimazole increased the risk of transplant rejection in patients receiving tacrolimus therapy. Patient data were acquired from the US Food and Drug Administration's Adverse Event Reporting System (FAERS) from the first quarter of 2004 to the end of 2017. Next, we retrospectively investigated the effect of clotrimazole troche on tacrolimus pharmacokinetics in seven patients who underwent heart transplantation between March and December 2017. RESULTS: The FAERS subset data indicated a significant association between transplant rejection and tacrolimus with clotrimazole [reporting odds ratio 1.92, 95% two-sided confidence interval (95% CI) 1.43-2.58, information component 0.81, 95% CI 0.40-1.23]. The pharmacokinetic study demonstrated a significant correlation between trough concentration (C0) and area under the concentration-time curve of tacrolimus after discontinuation of clotrimazole (R2 = 0.60, P < 0.05) but not before its discontinuation. Furthermore, the median clearance/bioavailability of tacrolimus after discontinuation of clotrimazole was 2.2-fold greater than that before its discontinuation (0.27 vs. 0.59 L/h/kg, P < 0.05). The median C0 decreased from 10.7 ng/mL on the day after discontinuation of clotrimazole to 6.5 ng/mL at 1 day and 5.3 ng/mL at 2 days after its discontinuation. CONCLUSION: Immediate dose adjustments of tacrolimus may be beneficial to avoid transplant rejection when clotrimazole troche is added or discontinued.

Comparison of CYP3A5*3 genotyping assays for personalizing immunosuppressive therapy in heart transplant patients
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OBJECTIVE: This study aimed to compare a novel point-of-care assay that involves a flap endonuclease reaction performed using GTS-7000® to a conventional assay that involves DNA sequencing performed using 3130xl Genetic Analyzers*. MATERIALS AND METHODS: This study enrolled 74 patients who underwent heart transplantation at the National Cerebral and Cardiovascular Center between May 2004 and October 2016. Each patient was genotyped as cytochrome P450 (CYP) 3A5*1/*1, -CYP3A5*1/*3, or CYP3A5*3/*3. Quantitative and qualitative comparison between the two assays was carried out. RESULTS: Four patients were genotyped as CYP3A5*1/*1, 25 as CYP3A5*1/*3, and 45 as CYP3A5*3/*3. Genotyping results of the point-of-care method were completely consistent with those of the conventional method. The total analysis time of the point-of-care method was shorter than that of the conventional method (~ 1.5 vs. 7.5 h). However, the cost of the point-of-care method was higher than that of the conventional method (~ 21 vs. 17 US$). CONCLUSION: Compared with a laboratory-based assay, the point-of-care assay that utilizes GTS-7000® is accurate and rapid despite being slightly more expensive. Further trials using this assay are warranted.

Effects of clotrimazole on tacrolimus pharmacokinetics in patients with heart transplants with different CYP3A5 genotypes.

PURPOSE: This study aimed to investigate the effects of clotrimazole on the pharmacokinetics of tacrolimus in Japanese patients with heart transplants with different CYP3A5 genotypes. METHODS: Twenty-six patients who underwent heart transplantation between June 2012 and July 2017 were enrolled in this retrospective study. The CYP3A5 (rs776746; CYP3A5*3) genotype was determined after monitoring and analysing tacrolimus blood concentrations. The pharmacokinetic profile of tacrolimus was examined before and after the discontinuation of clotrimazole and in patients with different CYP3A5 genotypes. RESULTS: The CYP3A5*1/*1, *1/*3 and *3/*3 genotypes were detected in 2, 8 and 16 patients, respectively. After clotrimazole was discontinued, the CYP3A5 expresser (CYP3A5*1/*1 or *1/*3) group had a 3.3-fold median increase in apparent oral clearance of tacrolimus (0.27 vs. 0.89 L/h/kg, P = 0.002) compared with the CYP3A5 non-expresser (CYP3A5*3/*3) group with a 2.2-fold median increase (0.18 vs. 0.39 L/h/kg, P < 0.0001). Significant correlations were observed between C0 and area under the concentration-time curve (AUC0-12) of tacrolimus after the discontinuation of clotrimazole in the CYP3A5 expresser and non-expresser groups, respectively (R2 = 0.49 and 0.42, all P < 0.05), but not before the discontinuation of clotrimazole. CONCLUSION: The effects of clotrimazole on tacrolimus pharmacokinetics in the CYP3A5 expresser patients were significantly greater than those in the CYP3A5 non-expresser patients. In addition, clotrimazole disturbed the correlation between C0 and AUC0-12 of tacrolimus. Careful dose adjustment of tacrolimus based on CYP3A5 genotypes may be beneficial for the patients with heart transplants who are concomitantly treated with clotrimazole.

Changes in blood concentration of mycophenolic acid and FK506 in a heart-transplant patient treated with plasmapheresis
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OBJECTIVE: Prior to heart transplant, sensitization to human leukocyte antigen can occur after blood transfusions used during implantation of ventricular assist devices. The result is an increased risk of antibody-mediated rejection (AMR) after heart transplant. While plasmapheresis (PPH) treats serious AMR cases, what subsequent changes occur in the blood concentrations of immunosuppressive agents is still unknown. We investigated pre- and post-PPH changes in blood concentrations of tacrolimus (FK506) and mycophenolic acid (MPA) in a heart-transplant patient experiencing AMR. CASE: A 40-year-old woman with a history of dilated cardiomyopathy had heart transplantation for advanced heart failure. Since the patient was donor-specific antibody-positive and at risk for AMR, intravenous immunoglobulin therapy and PPH were performed just before transplantation. Triple combination immunosuppressive therapy was initiated, but 4 days after transplantation, panel-reactive antibody increased drastically, and AMR was diagnosed by biopsy. Multidisciplinary therapy, including PPH, was performed. Blood samples were collected to measure blood concentrations of FK506 and MPA before and after passage through the plasma separator. RESULTS: The elimination efficiency of FK506 from PPH was -6.25 - 2.25%, while the elimination efficiency of MPA was much greater at 32.35 - 51.43%. CONCLUSION: These results show the necessity of carefully considering changes in blood concentrations that occur in immunosuppressive agents due to PPH, including the pharmacokinetics of the particular drug. However, proper timing of the PPH relative to drug administration can also minimize immunosuppressant loss.
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De novo malignancy in heart transplant recipients: A single center experience in Japan.

BACKGROUND: Because of aggressive immunosuppression, heart transplant recipients have a high risk of de novo malignancy, which is a major cause of death and worse prognosis, regardless of the type. However, the impact of de novo malignancy on Japanese heart transplant recipients is unknown. METHODS: We analyzed 103 Japanese heart transplant recipients over 18-years-old at the time of transplantation between April 1999 and April 2017. Patient characteristics and prognosis were compared between heart transplant recipients with or without de novo malignancy after heart transplantation (HTx). Additionally, univariate and multivariate analyses for the risk factors of de novo malignancy after HTx were performed. RESULTS: De novo malignancy developed in 7 patients (6.8%; post-transplant lymphoproliferative disorders, n=3; Bowen's disease, n=1; colon cancer, n=2; bladder cancer, n=1). Follow-up time and previous antibody mediated rejection (AMR)≥grade 1 were risk factors of de novo malignancy after HTx in multivariate analysis (OR: 1.19, 95% CI: 1.00-1.42, p=0.043; and OR: 10.7, 95% CI: 1.37-83.68, p=0.038, respectively). History of malignancy was a potential risk factor, albeit not significant (OR: 23.05, 95% CI: 0.99-534.53, p=0.071). The survival rates in patients with de novo malignancy was significantly lower than in those without de novo malignancy (3-year survival rate: 100% versus 67%, p=0.0025). CONCLUSIONS: Long follow-up time and previous AMR≥grade 1 were risk factors of de novo malignancy after HTx. Japanese heart transplant recipients with de novo malignancy have worse prognosis; therefore, screening examinations are important for early diagnosis.

Impact of Coronary Artery Calcification in the Donor Heart on Transmitted Coronary Artery Disease in Heart Transplant Recipients.

BACKGROUND: Coronary artery disease (CAD) after heart transplantation (HTx) develops as a combination of donor-transmitted coronary atherosclerosis (DTCA) and cardiac allograft vasculopathy. Assessing donor CAD before procurement is important. Because coronary artery calcification (CAC) is a predictor for CAD, donor-heart CAC is usually evaluated to estimate the risk of donor CAD. The usefulness of CAC for predicting DTCA, however, is not known. Methods and Results: Sixty-four HTx recipients whose donor underwent chest computed tomography before procurement or ≤2 weeks after HTx and who underwent coronary angiography and intravascular ultrasound (IVUS) ≤3 months after HTx were enrolled. Eight patients had CAC (CAC group) and 56 patients did not have CAC (no-CAC group). Patients in the CAC group were significantly older and had a higher prevalence of maximum intimal thickness (MIT) of the coronary artery ≥0.5 mm at initial IVUS than patients in the no-CAC group (100% vs. 55%, P=0.02). Adverse cardiac events and death were not significantly different. Everolimus tended to be used more often in the CAC group. CONCLUSIONS: Donor-heart CAC is a significant predictor for MIT of the coronary artery ≥0.5 mm after HTx. The presence of CAC, however, is not associated with future cardiac events. The higher prevalence of everolimus use in the CAC group may have affected the results.

Effects of vitamin K epoxide reductase complex 1 gene polymorphisms on warfarin control in Japanese patients with left ventricular assist devices (LVAD).

PURPOSE: This study aimed to investigate relationships between times in therapeutic range (TTR) or warfarin sensitivity indexes (WSI) and VKORC1-1639G>A and CYP2C9 polymorphisms in patients with left ventricular assist devices (LVAD). METHODS: Severe heart failure patients who received LVAD from January 1, 2013 to October 31, 2017 were recruited. Relationships between TTR or WSI and VKORC1-1639G>A and CYP2C9 gene polymorphisms were investigated immediately after LVAD implantation (period 1) and immediately prior to hospital discharge (period 2). RESULTS: Among 54 patients, 31 (72.1%) had VKORC1-1639AA and CYP2C9*1/*1 (AA group) polymorphisms and 12 (27.9%) had VKORC1-1639GA and CYP2C9*1/*1 (GA group) polymorphisms. During period 1, mean prothrombin time-international normalized ratio (PT-INR) values were significantly higher in the AA group than in the GA group (2.21 vs. 2.05, p < 0.0001). Mean WSI values were 1.68-fold greater in the AA group than in the GA group (1.14 vs. 0.68, p < 0.0001). In addition, times below the therapeutic range (TBTR) in the GA group were significantly greater than in the AA group during period 1 (39.8 vs. 28.3%, p = 0.032), and insufficient PT-INR was more frequent in the GA group than in the AA group. However, mean PT-INR values during period 2 did not differ and no significant differences in TTR, TATR, and TBTR values were identified. In subsequent multivariable logistic regression analyses, the VKORC1-1639GA allele was significantly associated with insufficient anticoagulation. CONCLUSION: Patients with the VKORC1-1639GA and CYP2C9*1/*1 alleles may receive insufficient anticoagulation therapy during the early stages after implantation of LVAD, and VKORC1-1639G>A and CYP2C9 genotyping may contribute to more appropriate anticoagulant therapy after implantation of LVAD.

Impact of the CYP3A5*1 Allele on the Pharmacokinetics of Tacrolimus in Japanese Heart Transplant Patients.

BACKGROUND AND OBJECTIVE: Tacrolimus, a major immunosuppressant used after transplantation, is associated with large interindividual variation involving genetic polymorphisms in metabolic processes. A common variant of the cytochrome P450 (CYP) 3A5 gene, CYP3A5*3, affects blood concentrations of tacrolimus. However, tacrolimus pharmacokinetics at the early stage of transplantation have not been adequately studied in heart transplantation. We retrospectively examined the impact of the CYP3A5 genotype on tacrolimus pharmacokinetics at the early stage of heart transplantation. METHODS: The tacrolimus pharmacokinetic profile was obtained from 65 patients during the first 5 weeks after heart transplantation. Differences in the patients' characteristics and tacrolimus pharmacokinetic parameters between the CYP3A5 expresser (*1/*1 or *1/*3 genotypes) and non-expresser (*3/*3 genotype) groups were assessed by the Chi-square test, Student's t test, or Mann-Whitney U test. RESULTS: The CYP3A5 *1/*1, *1/*3, and *3/*3 genotypes were detected in 5, 22, and 38 patients, respectively. All patients started clotrimazole therapy approximately 1 week after starting tacrolimus. Apparent clearance and dose/weight to reach the target trough concentration (C0) were significantly higher in the expresser group than in the non-expresser group (0.32 vs. 0.19 L/h/kg, p = 0.0003; 0.052 vs. 0.034 mg/kg/day, p = 0.0002); there were no significant differences in the area under the concentration-time curve from 0 to 12 h (AUC0-12) and concentrations at any sampling time point between the two groups. CONCLUSION: Similar concentration-time curves for tacrolimus were obtained in the expresser and non-expresser groups by dose adjustment based on therapeutic drug monitoring. These results demonstrate the importance of the CYP3A5 genotype in tacrolimus dose optimization based on therapeutic drug monitoring after heart transplantation.

Effect of fluconazole on the pharmacokinetics of everolimus and tacrolimus in a heart transplant recipient: Case report.

OBJECTIVE: Everolimus is an inhibitor of the mammalian target of rapamycin (mTOR) and has been used in combination with calcineurin inhibitors (tacrolimus and cyclosporine) to prevent allograft rejection following organ transplantation. In heart transplant recipients, everolimus should be maintained at a target blood concentration of 3 - 8 ng/mL, in combination with reduced-dose calcineurin inhibitors and therefore, requires strict monitoring. Fluconazole, an azole antifungal agent, affects blood concentration of tacrolimus by inhibiting the cytochromes P450 (CYP) 3A4 and 3A5. Therefore, to avoid overexposure during everolimus-azole cotreatment, the dose of everolimus should be reduced. However, the mechanism of interaction between everolimus and fluconazole remains unclear. CASE REPORT: We report the case of a heart transplant recipient who experienced a 2.8-fold increase in everolimus clearance and a 3.5-fold increase in everolimus dosage, following withdrawal of fluconazole therapy. The clearance and dosage of tacrolimus increased 4.7- and 3.0-fold, respectively. CONCLUSION: The concentrations of everolimus and tacrolimus should be carefully monitored when administered concomitantly with fluconazole to heart transplant recipients. The patient in this case had a CYP3A5*1/*3 genotype, and CYP3A5 constituted the metabolic pathway. Therefore, concomitant use of fluconazole might have a relatively small impact on everolimus and tacrolimus pharmacokinetics in this case.
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Use of rifabutin to treat tuberculosis in a cardiac transplant recipient: A case report
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OBJECTIVE: Tuberculosis is an important concern following organ transplantation. Unfortunately, several antituberculosis drugs interact with immunosuppressants. This report describes our experience with rifabutin (RBT) in the treatment of acute tuberculosis in a cardiac transplant recipient. CASE: A 61-year-old cardiac transplant recipient developed tuberculosis meningitis during treatment of miliary tuberculosis. RBT was given for 27 days concomitantly with cyclosporine (CsA). CsA concentrations at 0 hour (C0) decreased within 3 days of starting RBT. The serum concentration-curve from 0 to 12 hours (AUC0-12h)/dose 7 days after starting RBT therapy decreased by 28%, compared to the values before RBT therapy. The apparent clearance at both 7 and 21 days after starting RBT therapy was 1.4 times higher than before RBT therapy. CONCLUSION: RBT has fewer drug-drug interactions than rifampin and should be preferentially used for the treatment of tuberculosis in transplant patients treated with CsA. Close monitoring of CsA blood concentration during RBT therapy minimized the risk of under- or over-immunosuppression in a cardiac transplant patient.
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Association between Serum Amiodarone and N-Desethylamiodarone Concentrations and Development of Thyroid Dysfunction.

OBJECTIVE: This retrospective cohort study was performed to examine the association between serum amiodarone (AMD) and N-desethylamiodarone (DEA) concentrations and the development of thyroid dysfunction. METHODS: Patients treated with AMD from January 2012 to April 2016 were identified from the computerized hospital information system database at the National Cerebral and Cardiovascular Center. Only patients whose serum AMD and DEA concentrations had been determined at least once were included in the study. RESULTS: A total of 377 patients were enrolled. Consequently, 54 (14.3%) and 60 (15.9%) patients who developed AMD-induced thyrotoxicosis and hypothyroidism were included. The mean DEA/AMD ratio during the pre-index period in the thyrotoxicosis group (0.86 ± 0.24) was significantly higher than in the hypothyroidism (0.68 ± 0.27) and euthyroidism (0.78 ± 0.30; p < 0.0001) groups. In addition, the mean DEA/AMD ratio during the post-index period in the thyrotoxicosis group (1.05 ± 0.40) was significantly higher than in the hypothyroidism (0.81 ± 0.24) and euthyroidism (0.88 ± 0.22; p < 0.0001) groups. A persistently higher DEA/AMD ratio was observed throughout the study period in the thyrotoxicosis group. In addition, good correlations between the DEA/AMD ratio and the levels of free thyroxine, free triiodothyronine levels, and log (thyroid-stimulating hormone) were observed in the thyrotoxicosis and euthyroidism groups. CONCLUSION: Patients with AMD-induced thyrotoxicosis had an increased DEA/AMD ratio and patients with AMD-induced hypothyroidism had a decreased DEA/AMD ratio before the development of thyroid dysfunction. The DEA/AMD ratio may be a predictive marker for AMD-induced thyroid dysfunction.

Gastrointestinal risk factors and prescribing pattern of antiulcer agents in patients taking low-dose aspirin in Japan.

OBJECTIVES: To identify prescribing patterns of antiulcer agents in patients on low-dose aspirin (LDA) and to evaluate the number of gastrointestinal (GI) risk factors of the patients. METHODS: A retrospective chart review of patients taking LDA was conducted at the National Cerebral and Cardiovascular Center in Japan. The rate of concomitant use of antiulcer agents and the risk of each patient to develop GI complications were evaluated. RESULTS: Of the 314 patients, 64 were not on antiulcer agents and 55 of them had >1 risk factor. More patients not on antiulcer agents had started LDA before hospitalization. CONCLUSION: The rate of coprescribing antiulcer agents with LDA was high. However, the timing of initiating LDA therapy affected the prescribing pattern of antiulcer agents.

The influence of residual apixaban on bleeding complications during and after catheter ablation of atrial fibrillation.

BACKGROUND: The periprocedural protocol for atrial fibrillation (AF) ablation commonly includes anticoagulation therapy. Apixaban, a direct oral anticoagulant, is currently approved for clinical use; however, little is known about the effects of residual apixaban concentration on bleeding complications during/after AF ablation. Therefore, we measured residual apixaban concentration by using mass spectrometry and examined the anticoagulant's residual effects on bleeding complications. METHODS: Fifty-eight patients (Mean age of 64.7±12.5 years; 31 males, 27 females) were enrolled and administered apixaban twice daily. We analyzed trough apixaban concentration, activated clotting time (ACT), heparin dose, and bleeding complications during/after AF ablation. Apixaban concentrations were directly measured using mass spectrometry. RESULTS: Bleeding complications were observed in 19 patients (delayed hemostasis at the puncture site, 16; hematuria, 3; hemosputum, 1). No patient required blood transfusion. The mean trough apixaban concentration was significantly lower in patients with bleeding complications than without (152.4±73.1 vs. 206.8±98.8 ng/mL respectively, P=0.037), while the heparin dose to achieve ACT>300 s was significantly higher in patients with bleeding complications (9368.4±2929.0 vs. 7987.2±2135.2 U/body respectively, P=0.046). Interestingly, a negative correlation was found between the trough apixaban concentration and the heparin dose to achieve ACT>300 s (P=0.033, R=-0.281). CONCLUSIONS: Low residual plasma apixaban is associated with a higher incidence of bleeding complications during/after AF ablation, potentially because of a greater heparin requirement during AF ablation.