| 1. |
- Imamura, Teruhiko, et al.
(författare)
-
A case with recovery of response to tolvaptan associated with remission of acute kidney injury and increased urine osmolality
- 2013
-
Ingår i: International Heart Journal. - : International Heart Journal Association. - 1349-2365 .- 1349-3299. ; 54:2, s. 115-118
-
Tidskriftsartikel (refereegranskat)abstract
- Tolvaptan (TLV), a vasopressin type 2 receptor antagonist, has been demonstrated to be effective in patients with decompensated heart failure (HF) refractory to incremental doses of diuretics, but the responsiveness has not always been predictable. We have recently proposed that urine osmolality (U-OSM) is a valuable parameter for the prediction of responses to TLV, because U-OSM reflects the activity of the collecting ducts, where TLV plays its unique role. Acute kidney injury (AKI) is often associated with severe tubular dysfunction, including the collecting ducts, and in such cases a response to TLV may not be expected. We here experienced a patient with HF and AKI in whom TLV was not effective during AKI. We also observed recovery of responsiveness to TLV along with remission of AKI as well as increased U-OSM later on. We believe that this is the first report on the reversibility of the TLV response in relation to U-OSM.
|
|
| 2. |
- Imamura, Teruhiko, et al.
(författare)
-
Acute pulmonary vasoreactivity test with sildenafil or nitric monoxide before left ventricular assist device implantation
- 2013
-
Ingår i: Journal of Artificial Organs. - : Springer Verlag (Germany). - 1434-7229 .- 1619-0904. ; 16:3, s. 389-392
-
Tidskriftsartikel (refereegranskat)abstract
- There has been no established medical therapy to ameliorate pulmonary hypertension (PH) owing to left heart disease (LHD-PH). It has recently been shown that the left ventricular assist device (LVAD) can improve LHD-PH and therefore has the potential to become a major bridge tool for heart transplantation (HTx). However, some patients still have persistent PH even after LVAD treatment. It is essential to demonstrate the reversibility of end-organ dysfunction, including PH, prior to implantable LVAD treatment, especially in Japan, because implantable LVAD treatment is indicated only as bridge to transplantation. Here we report a patient with LHD-PH whose PH was demonstrated to be reversible by the acute pulmonary vasoreactivity test (APVT) with nitrogen monoxide (NO) and the phosphodiesterase-5 inhibitor sildenafil. Both inhaled NO and sildenafil reduced pulmonary vascular resistance, but pulmonary capillary wedge pressure was increased by NO, which was conversely decreased under increased cardiac output by sildenafil. After the patient was listed as an HTx recipient, pulmonary vascular resistance recovered down to an acceptable range with LVAD treatment. Based on these findings, we suggest that the APVT with sildenafil may be a useful and safe tool to predict improvement of PH after LVAD treatment.
|
|
| 3. |
- Imamura, Teruhiko, et al.
(författare)
-
Bosentan improved persistent pulmonary hypertension in a case after implantation of a left ventricular assist device
- 2013
-
Ingår i: Journal of Artificial Organs. - : Springer. - 1434-7229 .- 1619-0904. ; 16:1, s. 101-104
-
Tidskriftsartikel (refereegranskat)abstract
- No medical treatment has been established to ameliorate pulmonary hypertension (PH) due to left heart disease. Heart transplantation (HTx) is thus far the definitive therapy for stage D heart failure, but concomitant PH is one of the major risk factors for death after HTx. Recently, implantation of a left ventricular assist device (LVAD) has been reported to improve PH and has become a major bridge tool for HTx. We experienced a rare case with persistent PH even after the implantation of a continuous-flow LVAD. The administration of an endothelin receptor antagonist, bosentan, significantly decreased pulmonary vascular resistance. Combination therapy with LVAD implantation and anti-PH medication may be useful for patients with stage D heart failure complicated with severe PH.
|
|
| 4. |
- Imamura, Teruhiko, et al.
(författare)
-
Everolimus-incorporated immunosuppressant strategy improves renal dysfunction while maintaining low rejection rates after heart transplantation in Japanese patients
- 2013
-
Ingår i: International Heart Journal. - : International Heart Journal Association. - 1349-2365 .- 1349-3299. ; 54:4, s. 222-227
-
Tidskriftsartikel (refereegranskat)abstract
- The long-term survival of heart transplantation (HTx) recipients has increased significantly in recent years, however, the nephrotoxic adverse effects of calcineurin inhibitors (CNIs) are still a major concern. Recently, an inhibitor of mammalian target of rapamycin, everolimus (EVL), has emerged as an alternative immunosuppressant drug that may allow CM dosage reduction and thereby spare renal function. Data were collected from 20 HTx recipients who had received EVL (target trough level 3-8 ng/mL) along with a dose reduction of CNIs and/or mycophenolate mophetil (MMF) and had been followed for 1 year. Estimated glomerular filtration rate increased significantly with a reduction in the CM dosage in a dose-dependent manner (P less than 0.001, r = -0.807). Neutrophil count increased significantly (P less than 0.05) with a reduction in the dosage of MMF (P = 0.009, r = -0.671). Cytomegalovirus antigenemia remained negative after EVL administration among all candidates without any antiviral agents (P = 0.001). There were no significant increases in the acute rejection rates among recipients with EVL compared to those without EVL (P = 0.132). An immunosuppressant strategy incorporating EVL could reduce the CM and MMF dosages, which resulted in improvements in renal dysfunction and neutropenia while maintaining low rejection rates among HTx recipients.
|
|
| 5. |
- Imamura, Teruhiko, et al.
(författare)
-
Late-onset right ventricular failure in patients with preoperative small left ventricle after implantation of continuous flow left ventricular assist device
- 2014
-
Ingår i: Circulation Journal. - : Japanese Circulation Society. - 1346-9843 .- 1347-4820. ; 78:3, s. 625-633
-
Tidskriftsartikel (refereegranskat)abstract
- Background: The continuous flow (CF) left ventricular assist device (LVAD) has replaced the pulsatile flow (PF) LVAD because of its advantages of better patient survival and higher quality of life. However, "late-onset right ventricular failure (RVF)" after CF LVAD implantation has emerged as an increasing concern, but little is known about the mechanism. Methods and Results: We retrospectively analyzed the 3-month hemodynamic and echocardiographic data from 38 consecutive patients who had received CF LVADs, and from 22 patients who had received PF LVADs. Late-onset RVF was defined as persistent right ventricular stroke work index (RVSWI) less than4.0 g/m(2) at any rotation speed and after saline infusion test at 5 weeks after implantation of CF LVAD. Patients with late-onset RVF had significantly impaired exercise tolerance indicated by shorter 6-min walking distance and lower peak (V) over dot O-2, and worsened tricuspid regurgitation, together with enlargement of the RV under CF LVAD treatment (all Pless than0.05). Univariable analyses demonstrated that preoperative smaller LV diastolic diameter (LVDd) was the risk factor for late-onset RVF with a cutoff value of 64 mm calculated by ROC analysis (area under curve, 0.925). In contrast, there was no correlation between preoperative LVDd and postoperative RVSWI in the PF LVAD group, though their preoperative background was worse than that of the CF group. Conclusions: In the setting of preoperative small LVDd, CF LVAD may cause late-onset RVF by leftward shift of the interventricular septum.
|
|
| 6. |
- Imamura, Teruhiko, et al.
(författare)
-
Novel criteria of urine osmolality effectively predict response to tolvaptan in decompensated heart failure patients--association between non-responders and chronic kidney disease
- 2013
-
Ingår i: Circulation Journal. - : Japanese Circulation Society. - 1346-9843 .- 1347-4820. ; 77:2, s. 397-404
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND:A newly-developed vasopressin type 2 receptor antagonist, tolvaptan (TLV), has a unique feature of diuresis, but the response to this drug can be unpredictable.METHODS AND RESULTS:Data were collected from hospitalized patients with decompensated congestive heart failure who were administered TLV at 3.75-15 mg/day (n=61). A responder/non-responder to TLV was determined as having any increase/decrease in urine volume (UV) during the next 24h after TLV treatment on the first day. Logistic regression analyses for increases in UV were performed, and independent predictors of the responder were the following: C1, baseline urine osmolality (U-OSM) >352 mOsm/L; and C2, %decrease in U-OSM >26% at 4-6h after TLV administration. Criteria consisting of C1 and C2 had a good predictability for responders by receiver-operating characteristic analysis (area under the curve=0.960). Kidneys of the non-responders no longer had diluting ability (%decrease of U-OSM at 4-6h=2.7 ± 14.6%*), but also barely kept concentrating ability (baseline U-OSM=296.4 ± 68.7*mOsm/L) with markedly reduced estimated glomerular filtration ratio (35.5 ± 29.4 m l · min(-1) · 1.73 m(-2)*) (*P<0.05 vs. patients who had at least 1 positive condition [n=42]).CONCLUSIONS:More than 26% decrease in U-OSM from a baseline >352 mOsm/L for the first 4-6h predicts responders to TLV. Unresponsiveness to TLV is attributable to nephrogenic diabetes insipidus complicated by chronic renal disease.
|
|
| 7. |
- Imamura, Teruhiko, et al.
(författare)
-
Successful Conversion From Thiazide to Tolvaptan in a Patient With Stage D Heart Failure and Chronic Kidney Disease Before Heart Transplantation
- 2013
-
Ingår i: International Heart Journal. - : International Heart Journal Association. - 1349-2365 .- 1349-3299. ; 54:1, s. 48-50
-
Tidskriftsartikel (refereegranskat)abstract
- Chronic kidney disease (CKD) is often complicated with advanced heart failure because of not only renal congestion and decreased renal perfusion but also prolonged use of diuretics at higher doses, which sometimes results in hyponatremia. Preoperative CKD is known to be associated with poor prognosis after heart transplantation (HTx). We experienced a stage D heart failure patient with CKD and hyponatremia who was switched from trichlormethiazide to tolvaptan. His hyponatremia was normalized, and his renal function was improved after conversion to tolvaptan. In patients with stage D heart failure, it may be useful to administer tolvaptan with a concomitant reduction in the dose of diuretics in order to preserve renal function and avoid hyponatremia before HTx.
|
|
| 8. |
- Imamura, Teruhiko, et al.
(författare)
-
Successful treatment of hemodynamic compromise caused by antibody-mediated and cellular rejection in a recipient 12 years after heart transplantation
- 2013
-
Ingår i: International Heart Journal. - : International Heart Journal Association. - 1349-2365 .- 1349-3299. ; 54:5, s. 328-331
-
Tidskriftsartikel (refereegranskat)abstract
- Heart transplantation (HTx) is an established therapy for stage D heart failure due to recent advances in immunosuppressive regimens. However, antibody-mediated rejection remains an unsolved problem because of its refractoriness to standard immunosuppressive therapy with high mortality and graft loss. We experienced a 16-year old patient with hemodynamic compromise caused by both cellular and antibody-mediated rejection 12 years after HTx. The rejection was refractory to repeated steroid pulse treatment, intravenous immunoglobulin administration, and intensifying immunosuppression including addition of everolimus. Eventually, she was successfully treated with repeated plasma exchange accompanied by a single administration of the anti-CD20 monoclonal antibody rituximab.
|
|
| 9. |
- Imamura, Teruhiko, et al.
(författare)
-
Tolvaptan Can Improve Clinical Course in Responders Validation Analysis for the Definition of Responsiveness by Urine Volume
- 2013
-
Ingår i: International Heart Journal. - : International Heart Journal Association. - 1349-2365 .- 1349-3299. ; 54:6, s. 377-381
-
Tidskriftsartikel (refereegranskat)abstract
- We previously defined "responders" as patients with increases in urine volume (UV) on day 1 after the administration of tolvaptan (TLV), and demonstrated that responders to TLV could be predicted with considerable accuracy by urine osmolality (U-OSM) levels. Responders and non-responders to TLV should be associated with different clinical courses after a certain time following TLV administration. Therefore, the aim of the present study was to validate our definition of responders by clinical parameters 1 week after administration of TLV. Data (n = 85) were obtained from in-hospital patients with decompensated heart failure (HF) who had received TLV at 3.75-15 mg daily, and clinical data at 1 week after the administration of Thy were compared with those of baseline. Sixty patients (70.6%) were "responders", in whom UV on day 1 increased after the administration of TLV compared with day 0. "Non-responders" were older, and had higher serum creatinine concentration and lower baseline U-OSM than "responders". Serum creatinine concentration increased significantly in "non-responders", but was unchanged in "responders". Body weight, plasma B-type natriuretic peptide concentration, and HF symptom score decreased significantly in "responders", but remained unchanged in "non-responders". Increases in UV after the first administration of TLV were closely correlated with improvement of congestive HF after 1 week of TLV treatment, which verified our definition of "responders" to TLV.
|
|
| 10. |
- Imamura, Teruhiko, et al.
(författare)
-
Urine osmolality estimated using urine urea nitrogen, sodium and creatinine can effectively predict response to tolvaptan in decompensated heart failure patients
- 2013
-
Ingår i: Circulation Journal. - : Japanese Circulation Society. - 1346-9843 .- 1347-4820. ; 77:5, s. 1208-1213
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND:Urine osmolality (U-OSM) is valuable to predict response to tolvaptan (TLV) in decompensated heart failure patients, but measurement of U-OSM is not always available on site.METHODS AND RESULTS:Data were collected from 66 hospitalized patients with decompensated heart failure who had received TLV at 3.75-15 mg/day. U-OSM, which was estimated using the following formula: 1.07×{2×[(urine sodium (mEq/L)]+[urine urea nitrogen (mg/dl)]/2.8+[urine creatinine (mg/dl)]×2/3}+16, was well correlated with the actual measurement (r=0.938, P<0.001). Criteria consisting of C1 (estimated baseline U-OSM>358 mOsm/L) and C2 (%decrease in estimated U-OSM>24% at 4-6 h after the first TLV dose) significantly discriminated responders from non-responders (P<0.05).CONCLUSIONS:Response to TLV can be predicted using U-OSM, which can be estimated using urine urea nitrogen, sodium, and creatinine concentration data.
|
|
