Impact of electrocardiogram-gated multi-slice computed tomography-based aortic annular measurement in the evaluation of paravalvular leakage following transcatheter aortic valve replacement: the efficacy of the OverSized AortiC Annular ratio (OSACA ratio) in TAVR

BACKGROUND

Even mild paravalvular leakage (PVL) after transcatheter aortic valve replacement (TAVR) is associated with increased late mortality. Electrocardiogram-gated multi-slice computed tomography (MSCT) enables detailed aortic annulus assessment. We describe the impact of MSCT for PVL following TAVR.

METHODS

Congruence between the prosthesis and annulus diameters affects PVL; therefore, we calculated the OverSized AortiC Annular ratio (OSACA ratio) and OSACA (transesophageal echocardiography, TEE) ratio as prosthesis diameter/annulus diameter on MSCT or TEE, respectively, and compared their relationship with PVL ≤ trace following TAVR.

RESULTS

Of 36 consecutive patients undergoing TAVR (Group A), the occurrence of PVL ≤ trace (33.3%) was significantly related to the OSACA ratio (p = 0.00020). In receiver-operating characteristics analysis, the cutoff value of 1.03 for the OSACA ratio had the highest sum of sensitivity (75.0%) and specificity (91.7%; AUC = 0.87) with significantly higher discriminatory performance for PVL as compared to the OSACA (TEE) ratio (AUC = 0.69, p = 0.028). In nine consecutive patients (Group B) undergoing TAVR based on guidelines formulated from our experience with Group A, PVL ≤ trace was significantly more frequent (88.9%) than that in Group A (p = 0.0060).

CONCLUSIONS

The OSACA ratio has a significantly higher discriminatory performance for PVL ≤ trace than the OSACA (TEE) ratio, and aortic annular measurement from MSCT is more accurate than that from TEE.

An adaptive model switching approach for phase I dose-finding trials

Model-based phase I dose-finding designs rely on a single model throughout the study for estimating the maximum tolerated dose (MTD). Thus, one major concern is about the choice of the most suitable model to be used. This is important because the dose allocation process and the MTD estimation depend on whether or not the model is reliable, or whether or not it gives a better fit to toxicity data. The aim of our work was to propose a method that would remove the need for a model choice prior to the trial onset and then allow it sequentially at each patient's inclusion. In this paper, we described model checking approach based on the posterior predictive check and model comparison approach based on the deviance information criterion, in order to identify a more reliable or better model during the course of a trial and to support clinical decision making. Further, we presented two model switching designs for a phase I cancer trial that were based on the aforementioned approaches, and performed a comparison between designs with or without model switching, through a simulation study. The results showed that the proposed designs had the advantage of decreasing certain risks, such as those of poor dose allocation and failure to find the MTD, which could occur if the model is misspecified.

Japanese nationwide multi-institutional cohort study of prostate cancer brachytherapy with permanent seed implantation

e16090

Background: Brachytherapy with permanent iodine-125 seed implantation (PI) has been approved in 2003 in Japan. Multi-institutional cohort study (Japanese Prostate Cancer Outcome Study of Permanent Seed Implantation; J-POPS, NCT00534196) assessing the treatment feature, efficacy, safety and health-related quality of life (QOL) has started in July 2005. Six thousand nine hundred and twenty-seven cases were enrolled to this study until December 2010 from 68 institutes around the country, which is approximately 40% of all the cases treated in Japan at that time. Methods: Patient’s background, cancer character, treatment feature such as combined therapy of external beam or hormone, post PI dosimetric information, treatment efficacy with PSA level, voiding symptoms with IPSS and treatment related adverse events according to NCI-CTCAE are investigated. PSA was measured every 3 months and symptoms accompanied to the treatment were assessed 3 to 6 months after the treatment. Backgrounds and treatment assessments of 2,341 patients enrolled in J-POPS during the initial 2 years are evaluated. Results: Patients’ age ranged from 45 to 89 (median 69) year-old and 99.0% of the cases were performance status 0 (ECOG criteria). Family history of prostate cancer was seen in 6.2%. PSA levels on cancer diagnosis were 1.60 to 42.0 (mean 6.80) ng/ml, clinical stage T2a or less was 89.9%, T2b was 5.2%, T2c was 2.9% and T3a-T3b was 0.8%. Gleason score (GS) less than 7 was 56.6%, GS 7 was 39.7%, and GS above 7 was 3.6%. According to NCCN risk classification, 44.2% was classified as low risk, 48.3% as intermediate risk and 5.7% as high risk. Androgen deprivation therapy (ADT) was performed in 48.5% of the patients and 23.4% was combined with external beam radiation therapy (EBRT). CT scan based first post therapeutic month dosimetry revealed that prostatic mean V100 and D90 for the cases treated with seed alone were 94.8% and 160.7 Gy, respectively. As for adequate control of radiation dose at rectum (mean R100 = 0.3 cc) and urethra (mean D5 = 223.4 Gy), high grade toxicities appeared very seldom. Conclusions: Outcomes of J-POPS will produce clinical evidence of PI that can be internationally accepted.

A new design for phase II single-arm clinical trials: Bayesian predictive sample size selection design

6576

Background: The aim of phase II trials is to determine if a new treatment is promising for further testing in confirmatory clinical trials. Most phase II clinical trials are designed as single-arm trials using a binary outcome with or without interim monitoring for early stopping. In this context, we propose a Bayesian adaptive design denoted as PSSD, predictive sample size selection design (Statistics in Medicine 2012;31:4243-4254). Methods: The design allows for sample size selection followed by any planned interim analyses for early stopping of a trial, together with sample size determination before starting the trial. In the PSSD, we determined the sample size using the predictive probability criterion with two kinds of prior distributions, that is, an ‘analysis prior’ used to compute posterior probabilities and a ‘design prior’ used to obtain prior predictive distributions. In the sample size determination, we provide two sample sizes, that is, N and Nmax, using two types of design priors. At each interim analysis, we calculate the predictive probability of achieving a successful result at the end of the trial using analysis prior in order to stop the trial in case of low or high efficacy, and we select an optimal sample size, that is, either N or Nmax as needed, on the basis of the predictive probabilities. Results: We investigated the operating characteristics through simulation studies, and the PSSD retrospectively applies to a lung cancer clinical trial. As the number of interim looks increases, the probability of type I errors slightly decreases, and that of type II errors increases. The type I error probabilities of the probabilities of the proposed PSSD are almost similar to those of the non-adaptive design. The type II error probabilities in the PSSD are between those of the two fixed sample size (N or Nmax) designs. Conclusions: From a practical standpoint, the proposed design could be useful in phase II single-arm clinical trials with a binary endpoint. In the near future, this approach will be implemented in actual clinical trials to assess its usefulness and to extend it to more complicated clinical trials.

A slow-releasing form of prostacyclin agonist (ONO1301SR) enhances endogenous secretion of multiple cardiotherapeutic cytokines and improves cardiac function in a rapid-pacing-induced model of canine heart failure

OBJECTIVES

Cardiac functional deterioration in dilated cardiomyopathy (DCM) is known to be reversed by intramyocardial up-regulation of multiple cardioprotective factors, whereas a prostacyclin analog, ONO1301, has been shown to paracrinally activate interstitial cells to release a variety of protective factors. We here hypothesized that intramyocardial delivery of a slow-releasing form of ONO1301 (ONO1301SR) might activate regional myocardium to up-regulate cardiotherapeutic factors, leading to regional and global functional recovery in DCM.

METHODS AND RESULTS

ONO1301 elevated messenger RNA and protein level of hepatocyte growth factor, vascular endothelial growth factor, and stromal-derived factor-1 of normal human dermal fibroblasts in a dose-dependent manner in vitro. Intramyocardial delivery of ONO1301SR, which is ONO1301 mixed with polylactic and glycolic acid polymer (PLGA), but not that of PLGA only, yielded significant global functional recovery in a canine rapid pacing-induced DCM model, assessed by echocardiography and cardiac catheterization (n = 5 each). Importantly, speckle-tracking echocardiography unveiled significant regional functional recovery in the ONO1301-delivered territory, consistent to significantly increased vascular density, reduced interstitial collagen accumulation, attenuated myocyte hypertrophy, and reversed mitochondrial structure in the corresponding area.

CONCLUSIONS

Intramyocardial delivery of ONO1301SR, which is a PLGA-coated slow-releasing form of ONO1301, up-regulated multiple cardiotherapeutic factors in the injected territory, leading to region-specific reverse left ventricular remodeling and consequently a global functional recovery in a rapid-pacing-induced canine DCM model, warranting a further preclinical study to optimize this novel drug-delivery system to treat DCM.

A feasibility study of induction pemetrexed plus cisplatin followed by pleurectomy/decortication aimed at macroscopic complete resection for malignant pleural mesothelioma

A prospective multi-institutional study has been initiated in Japan to evaluate the feasibility of induction chemotherapy using pemetrexed plus cisplatin, followed by pleurectomy/decortication aimed at macroscopic complete resection in patients with resectable malignant pleural mesothelioma. The study was initiated on September 2012, for which 24 patients will be recruited over a period of 2 years. The primary endpoint is the macroscopic complete resection rate, regardless of the surgical technique employed (i.e. pleurectomy/decortication or extrapleural pneumonectomy). The secondary endpoints are the pleurectomy/decortication rate, macroscopic complete resection rate by pleurectomy/decortication, pulmonary function at 3 months after surgery, adverse events, treatment-related mortality, response rate to chemotherapy and 3-year overall survival rate.

Urgent management of rapid heart rate in patients with atrial fibrillation/flutter and left ventricular dysfunction: comparison of the ultra-short-acting β1-selective blocker landiolol with digoxin (J-Land Study)

BACKGROUND

A rapid heart rate (HR) during atrial fibrillation (AF) and atrial flutter (AFL) in left ventricular (LV) dysfunction often impairs cardiac performance. The J-Land study was conducted to compare the efficacy and safety of landiolol, an ultra-short-acting β-blocker, with those of digoxin for swift control of tachycardia in AF/AFL in patients with LV dysfunction.

METHODS AND RESULTS

The 200 patients with AF/AFL, HR ≥120beats/min, and LV ejection fraction 25-50% were randomized to receive either landiolol (n=93) or digoxin (n=107). Successful HR control was defined as ≥20% reduction in HR together with HR <110beats/min at 2h after starting intravenous administration of landiolol or digoxin. The dose of landiolol was adjusted in the range of 1-10µg·kg(-1)·min(-1) according to the patient's condition. The mean HR at baseline was 138.2±15.7 and 138.0±15.0beats/min in the landiolol and digoxin groups, respectively. Successful HR control was achieved in 48.0% of patients treated with landiolol and in 13.9% of patients treated with digoxin (P<0.0001). Serious adverse events were reported in 2 and 3 patients in each group, respectively.

CONCLUSIONS

Landiolol was more effective for controlling rapid HR than digoxin in AF/AFL patients with LV dysfunction, and could be considered as a therapeutic option in this clinical setting.

The significance and robustness of a plasma free amino acid (PFAA) profile-based multiplex function for detecting lung cancer

Background

We have recently reported on the changes in plasma free amino acid (PFAA) profiles in lung cancer patients and the efficacy of a PFAA-based, multivariate discrimination index for the early detection of lung cancer. In this study, we aimed to verify the usefulness and robustness of PFAA profiling for detecting lung cancer using new test samples.

Methods

Plasma samples were collected from 171 lung cancer patients and 3849 controls without apparent cancer. PFAA levels were measured by high-performance liquid chromatography (HPLC)–electrospray ionization (ESI)–mass spectrometry (MS).

Results

High reproducibility was observed for both the change in the PFAA profiles in the lung cancer patients and the discriminating performance for lung cancer patients compared to previously reported results. Furthermore, multivariate discriminating functions obtained in previous studies clearly distinguished the lung cancer patients from the controls based on the area under the receiver-operator characteristics curve (AUC of ROC = 0.731 ~ 0.806), strongly suggesting the robustness of the methodology for clinical use. Moreover, the results suggested that the combinatorial use of this classifier and tumor markers improves the clinical performance of tumor markers.

Conclusions

These findings suggest that PFAA profiling, which involves a relatively simple plasma assay and imposes a low physical burden on subjects, has great potential for improving early detection of lung cancer.

Olfactory changes after endoscopic sinus surgery in patients with chronic rhinosinusitis

OBJECTIVE

To address the controversy over whether olfactory function is improved or not after endoscopic sinus surgery (ESS) in patients with eosinophilic (ECRS) and non-eosinophilic chronic rhinosinusitis (non-ECRS).

METHODS

Between June 2006 and March 2012, 89 adult patients with CRS underwent ESS at Hyogo College of Medicine. There were 55 men and 34 women with a mean age of 53 years old, ranging from 23 to 79 years. The average follow-up period was 10.7 months (3-24) after ESS. Peripheral blood examination, sinonasal CT imaging, and four kinds of olfaction tests [self-administered olfaction test (SAOQ), visual analog scale (VAS), T&T recognition threshold tests (T&T) and intravenous olfaction test using prosultiamine] were performed. We diagnosed ECRS when (i) symptoms of nasal congestion and olfactory disorder, (ii) bilateral chronic rhinosinusitis with nasal polyps (CRSwNPs), (iii) peripheral blood eosinophilia (>7.0%), and (iv) ethmoid sinus dominant opacification in preoperative CT findings (i.e. ethmoid sinuses (E) were more bilaterally occupied than those of maxillary sinuses (M), E/M≥1), were completely fulfilled. We divided the patients into two groups of ECRS (group A) and non-ECRS (group B). Olfaction tests before operation, and at the 3rd, 6th, 12th, and 24th month postoperation were analyzed. The severity and therapeutic evaluation of olfaction were based on criteria of T&T recognition thresholds.

RESULTS

The mean SAOQ and VAS scores showed significant improvement within 6 months after ESS in both group A and group B. In total, the improvement rates were 52.0% (26/50) at 3 months, 58.5% (24/41) at 6 months, 40.5% (15/37) at 12 months, and 41.2% (7/17) at 24 months. The significant improvement of T&T recognition thresholds in group B was maintained for 24 months, whereas those in group A, showing transient improvement, deteriorated after 12 months or more. A significant difference in postoperative T&T recognition between groups A and B was found at the 12th postoperative month. In both A and B, 84% of patients had a response to prosultiamine (positive group) in the preoperative stage. T&T thresholds in the positive group were significantly better that those in the negative groups in the postoperative stage.

CONCLUSION

Olfactory disorders due to ECRS showed transient improvement that deteriorated as time passed after surgery. The olfaction in the non-ECRS patients recovered comparatively well. Postoperative olfactory results were unfavorable in patients without a preoperative reaction to prosultiamine.

Lack of transient receptor potential melastatin 8 activation by phthalate esters that enhance contact hypersensitivity in mice

We studied the involvement of sensory neurons in skin sensitization to allergens using a mouse model in which the T-helper type 2 response is essential. Skin sensitization to fluorescein isothiocyanate (FITC) has been shown to be enhanced by several phthalate esters, including dibutyl phthalate (DBP). For different types of phthalate esters, we found a correlation between the ability of transient receptor potential (TRP) A1 activation and that of enhancing skin sensitization. A TRPA1-specific antagonist, HC-030031, was shown to suppress skin sensitization in the presence of DBP. However, since phthalate esters also activate TRPV1, phthalate esters could activate other types of TRP channels non-selectively. Furthermore, sensitization to FITC is also enhanced by menthol, which activates TRPA1 and TRPM8. Here we established an in vitro system for measuring TRPM8 activation. The selectivity for TRPM8 was established by the fact that two TRPM8 agonists (menthol and icilin) induced calcium mobilization, whereas agonists of TRPA1 and TRPV1 did not. We demonstrated that phthalate esters do not activate TRPM8. TRPA1-antagonist HC-030031 did not inhibit TRPM8 activation induced by menthol or icilin. These results show that phthalate esters activate TRPA1 and TRPV1 with selectivity. TRPM8 activation is not likely to be involved in the sensitization to FITC.

Use of scintigraphy to evaluate gastric accommodation and emptying: comparison with barostat

BACKGROUND AND AIM

Scintigraphy is a useful noninvasive technique for assessment of gastric motility, especially emptying, but there is little knowledge of use of the technique to assess gastric accommodation. Therefore, to clarify the usefulness of scintigraphy as a technique for assessing gastric accommodation, we compared scintigraphy with barostat, the gold standard modality.

METHODS

Twenty healthy volunteers (14 men, six women; mean age, 28.5 ± 5.4 years) were enrolled in the study. The volunteers ingested a radiolabeled ((99m) Tc) test meal and scintigraphic images were recorded. Radioactivity in the upper third and whole stomach was calculated to evaluate accommodation. In the barostat procedure, gastric accommodation was evaluated by measuring the maximum volume of the distended balloon. Thereafter, correlation between scintigraphic and barostat accommodation was investigated. Intra-and inter-observer variation of the scintigraphic test results were also assessed. Finally, the diagnostic performance of scintigraphy was evaluated by using sumatriptan as a positive control.

RESULTS

Measurements of accommodation by scintigraphy and barostat correlated (r = 0.524, P < 0.05). Sumatriptan significantly increased scintigraphically measured gastric accommodation (with sumatriptan, 51.5 ± 16.4%; without sumatriptan, 38.4 ± 13.8%) (P < 0.01), and had significantly (P < 0.05) delayed 50% half emptying time at 60, 90, 120, and 150 min after the start of the experiment. The data from repeated scintigraphic tests were highly reproducible (r = 0.804) with significant differences not observed among the investigators (inter-observer variation = 0.932, intra-observer variation = 0.898).

CONCLUSION

Gastric scintigraphy is a useful technique for assessing gastric accommodation and emptying.

The incidence of "silent" free air and aspiration pneumonia detected by CT after gastric endoscopic submucosal dissection

BACKGROUND

Although endoscopic submucosal dissection (ESD) is feasible as a treatment for early gastric cancer, it requires great skill to perform and may place patients at increased risk of a number of complications, including perforation and aspiration pneumonia.

OBJECTIVE

To investigate the incidence of "silent" free air without endoscopic perforation and aspiration pneumonia detected by CT after ESD and risk factors for the development of these 2 conditions.

DESIGN

Prospective cohort study.

SETTING

Single academic center.

PATIENTS

This study involved 87 patients with a total of 91 malignancies.

INTERVENTION

All patients underwent chest and abdominal CT and blood biochemistry analysis before and 1 day after ESD.

MAIN OUTCOME MEASUREMENTS

The incidence of silent free air and aspiration pneumonia after ESD and the related risk factors.

RESULTS

Silent free air was identified in 37.3% of patients without perforation. Tumor location (the upper portion of the stomach), the presence of a damaged muscular layer during ESD, and procedure time, but not specimen size, were significantly associated with silent free air (P = .006, P = .04, P = .02, and P = .53, respectively). According to the receiver-operating characteristic analysis, the resulting cutoff value of the procedure time for silent free air was 105 minutes (67.7% sensitivity, 65.4% specificity). Only procedure time (≥ 105 minutes) was an independent predictor of silent free air development (odds ratio 3.23; 95% confidence interval, 1.21-8.64; P = .02). On the other hand, aspiration pneumonia was seen in 6.6% of patients. Silent free air and aspiration pneumonia did not affect hospitalization.

LIMITATIONS

Single center and small number of patients.

CONCLUSIONS

Silent free air is frequently observed after ESD, and longer procedure time (≥ 105 minutes) was an independent risk factor for silent free air. However, silent free air and aspiration pneumonia detected by CT are not associated with clinically significant complications.

Feasibility, safety, and therapeutic efficacy of human induced pluripotent stem cell-derived cardiomyocyte sheets in a porcine ischemic cardiomyopathy model

BACKGROUND

Human induced pluripotent stem cell-derived cardiomyocytes (hiPS-CMs) are a promising source of cells for regenerating myocardium. However, several issues, especially the large-scale preparation of hiPS-CMs and elimination of undifferentiated iPS cells, must be resolved before hiPS cells can be used clinically. The cell-sheet technique is one of the useful methods for transplanting large numbers of cells. We hypothesized that hiPS-CM-sheet transplantation would be feasible, safe, and therapeutically effective for the treatment of ischemic cardiomyopathy.

METHODS AND RESULTS

Human iPS cells were established by infecting human dermal fibroblasts with a retrovirus carrying Oct3/4, Sox2, Klf4, and c-Myc. Cardiomyogenic differentiation was induced by WNT signaling molecules, yielding hiPS-CMs that were almost 90% positive for α-actinin, Nkx2.5, and cardiac troponin T. hiPS-CM sheets were created using thermoresponsive dishes and transplanted over the myocardial infarcts in a porcine model of ischemic cardiomyopathy induced by ameroid constriction of the left anterior descending coronary artery (n=6 for the iPS group receiving sheet transplantation and the sham-operated group; both groups received tacrolimus daily). Transplantation significantly improved cardiac performance and attenuated left ventricular remodeling. hiPS-CMs were detectable 8 weeks after transplantation, but very few survived long term. No teratoma formation was observed in animals that received hiPS-CM sheets.

CONCLUSIONS

The culture system used yields a large number of highly pure hiPS-CMs, and hiPS-CM sheets could improve cardiac function after ischemic cardiomyopathy. This newly developed culture system and the hiPS-CM sheets may provide a basis for the clinical use of hiPS cells in cardiac regeneration therapy.

Tissue- and plasma-specific MicroRNA signatures for atherosclerotic abdominal aortic aneurysm

BACKGROUND

Atherosclerotic abdominal aortic aneurysm (AAA) is a progressive, gradual aortic rupture that results in death in the absence of surgical intervention. Key factors that regulate initiation and progression of AAA are unknown, making targeted interventions difficult. MicroRNAs play a fundamental role in atherosclerosis, and atherosclerotic coronary artery disease is characterized by tissue- and plasma-specific microRNA signatures. However, little is known about microRNAs involved in AAA pathology. This study examined tissue and plasma microRNAs specifically associated with AAA.

METHODS AND RESULTS

AAA and normal wall tissues were sampled from patients undergoing AAA repair (n=13; mean age, 68±6 years) and aortic valve replacement surgery (n=7; mean age, 66±4 years), respectively. MicroRNA expression was assessed by high-throughput microRNA arrays and validated by real-time polymerase chain reaction for individual microRNAs that showed significant expression differences in the initial screening. MicroRNAs related to fibrosis (miR-29b), inflammation (miR-124a, miR-146a, miR-155, and miR-223), and endothelium (miR-126, let-7 family members, and miR-21) were significantly upregulated in AAA tissue. Significant negative correlations were seen in expression levels of monocyte chemoattractant protein-1 and miR-124a, -146a, and -223; tumor necrosis factor-α and miR-126 and -223; and transforming growth factor-β and miR-146a. Expression of microRNAs, such as miR-29b, miR-124a, miR-155, and miR-223, that were upregulated in AAA tissue was significantly reduced in plasma of patients with AAA (n=23; mean age, 72±9 years) compared to healthy controls (n=12; mean age, 51±11 years) and patients with coronary artery disease (n=17; mean age, 71±9 years).

CONCLUSIONS

The expression of some microRNAs was specifically upregulated in AAA tissue, warranting further studies on the microRNA function in AAA pathogenesis and on the possibility of using a microRNA biomarker for AAA diagnosis.

Intracoronary artery transplantation of cardiomyoblast-like cells from human adipose tissue-derived multi-lineage progenitor cells improve left ventricular dysfunction and survival in a swine model of chronic myocardial infarction

Transplantation of human cardiomyoblast-like cells (hCLCs) from human adipose tissue-derived multi-lineage progenitor cells improved left ventricular function and survival of rats with myocardial infarction. Here we examined the effect of intracoronary artery transplantation of human CLCs in a swine model of chronic heart failure. Twenty-four pigs underwent balloon-occlusion of the first diagonal branch followed by reperfusion, with a second balloon-occlusion of the left ascending coronary artery 1 week later followed by reperfusion. Four weeks after the second occlusion/reperfusion, 17 of the 18 surviving animals with severe chronic MI (ejection fraction <35% by echocardiography) were immunosuppressed then randomly assigned to receive either intracoronary artery transplantation of hCLCs hADMPCs or placebo lactic Ringer's solution with heparin. Intracoronary artery transplantation was followed by the distribution of DiI-stained hCLCs into the scarred myocardial milieu. Echocardiography at post-transplant days 4 and 8 weeks showed rescue and maintenance of cardiac function in the hCLCs transplanted group, but not in the control animals, indicating myocardial functional recovery by hCLCs intracoronary transplantation. At 8 week post-transplantation, 7 of 8 hCLCs transplanted animals were still alive compared with only 1 of the 5 control (p=0.0147). Histological studies at week 12 post-transplantation demonstrated engraftment of the pre DiI-stained hCLCs into the scarred myocardium and their expression of human specific alpha-cardiac actin. Human alpha cardiac actin-positive cells also expressed cardiac nuclear factors; nkx2.5 and GATA-4. Our results suggest that intracoronary artery transplantation of hCLCs is a potentially effective therapeutic strategy for future cardiac tissue regeneration.

A Bayesian predictive sample size selection design for single-arm exploratory clinical trials

The aim of an exploratory clinical trial is to determine whether a new intervention is promising for further testing in confirmatory clinical trials. Most exploratory clinical trials are designed as single-arm trials using a binary outcome with or without interim monitoring for early stopping. In this context, we propose a Bayesian adaptive design denoted as predictive sample size selection design (PSSD). The design allows for sample size selection following any planned interim analyses for early stopping of a trial, together with sample size determination before starting the trial. In the PSSD, we determine the sample size using the method proposed by Sambucini (Statistics in Medicine 2008; 27:1199-1224), which adopts a predictive probability criterion with two kinds of prior distributions, that is, an 'analysis prior' used to compute posterior probabilities and a 'design prior' used to obtain prior predictive distributions. In the sample size determination of the PSSD, we provide two sample sizes, that is, N and N(max) , using two types of design priors. At each interim analysis, we calculate the predictive probabilities of achieving a successful result at the end of the trial using the analysis prior in order to stop the trial in case of low or high efficacy (Lee et al., Clinical Trials 2008; 5:93-106), and we select an optimal sample size, that is, either N or N(max) as needed, on the basis of the predictive probabilities. We investigate the operating characteristics through simulation studies, and the PSSD retrospectively applies to a lung cancer clinical trial. (243)

Age-dependent decline of association between obesity and hyperglycemia in men and women

OBJECTIVE

The purpose of this study was to determine whether age influences the association between obesity and hyperglycemia.

RESEARCH DESIGN AND METHODS

The subjects were 57,576 Japanese male and female workers aged 35-70 years. The associations of adiposity indices, including BMI, waist circumference, and waist-to-height ratio, with risk for hyperglycemia were compared among different age groups (35-39, 40-49, 50-59, and 60-70 years) using odds ratios (ORs).

RESULTS

There were significant trends for the crude ORs of obese subjects versus nonobese subjects for hyperglycemia to be lower as age increased in men and women. Multivariate logistic regression analysis showed these trends of age-dependent decreases in ORs for hyperglycemia were not altered by adjustment for confounders such as smoking, alcohol drinking, and habitual exercise.

CONCLUSIONS

The results suggest that the association between obesity and hyperglycemia declines with age in men and women.

Does stringent restrictive annuloplasty for functional mitral regurgitation cause functional mitral stenosis and pulmonary hypertension?

BACKGROUND

It remains controversial whether restrictive mitral annuloplasty (RMA) for functional mitral regurgitation (MR) can induce functional mitral stenosis (MS) that may cause postoperative residual pulmonary hypertension (PH).

METHODS AND RESULTS

One hundred eight patients with left ventricular (LV) dysfunction and severe MR underwent RMA with stringent downsizing of the mitral annulus. Systolic pulmonary artery pressure (PAP) and mitral valve performance variables were determined by Doppler echocardiography prospectively and 1 month after RMA. Fifty-eight patients underwent postoperative hemodynamic measurements. Postoperative echocardiography showed a mean pressure half-time of 92 ± 14 ms, a transmitral mean gradient of 2.9 ± 1.1 mm Hg, and a mitral valve effective orifice area of 2.4 ± 0.4 cm(2), consistent with functional MS. Doppler-derived systolic PAP was 32 ± 8 mm Hg, which correlated weakly with the transmitral mean gradient (ρ=0.23, P=0.02). Postoperative cardiac catheterization also showed significant improvements in LV volume and systolic function, pulmonary capillary wedge pressure, cardiac index, and systolic PAP; the latter was associated with LV end-diastolic pressure [standardized partial regression coefficient (SPRC)=0.51], pulmonary vascular resistance (SPRC=0.47), cardiac index (SPRC=0.37), and transmitral pressure gradient (SPRC=0.20). In a multivariate Cox proportional hazard model, postoperative PH (systolic PAP >40 mm Hg), but not mitral valve performance variables, was strongly associated with adverse cardiac events.

CONCLUSIONS

RMA for functional MR resulted in varying degrees of functional MS. However, our data were more consistent with the residual PH being caused by LV dysfunction and pulmonary vascular disease than by the functional MS. The residual PH, not functional MS, was the major predictor of post-RMA adverse cardiac events.