Tapered catheter-based transurethral photoacoustic and ultrasonic endoscopy of the urinary system.

Early diagnosis is critical for treating bladder cancer, as this cancer is very aggressive and lethal if detected too late. To address this important clinical issue, a photoacoustic tomography (PAT)-based transabdominal imaging approach was suggested in previous reports, in which its in vivo feasibility was also demonstrated based on a small animal model. However, successful translation of this approach to real clinical settings would be challenging because the human bladder is located at a depth that far exceeds the typical penetration depth of PAT (∼3 cm for in vivo cases). In this study, we developed a tapered catheter-based, transurethral photoacoustic and ultrasonic endoscopic probe with a 2.8 mm outer diameter to investigate whether the well-known benefits of PAT can be harnessed to resolve unmet urological issues, including early diagnosis of bladder cancer. To demonstrate the in vivo imaging capability of the proposed imaging probe, we performed a rabbit model-based urinary system imaging experiment and acquired a 3D microvasculature map distributed in the wall of the urinary system, which is a first in PAT, to the best of our knowledge. We believe that the results strongly support the use of this transurethral imaging approach as a feasible strategy for addressing urological diagnosis issues.

Deep-Learning-Based Algorithm for the Removal of Electromagnetic Interference Noise in Photoacoustic Endoscopic Image Processing.

Despite all the expectations for photoacoustic endoscopy (PAE), there are still several technical issues that must be resolved before the technique can be successfully translated into clinics. Among these, electromagnetic interference (EMI) noise, in addition to the limited signal-to-noise ratio (SNR), have hindered the rapid development of related technologies. Unlike endoscopic ultrasound, in which the SNR can be increased by simply applying a higher pulsing voltage, there is a fundamental limitation in leveraging the SNR of PAE signals because they are mostly determined by the optical pulse energy applied, which must be within the safety limits. Moreover, a typical PAE hardware situation requires a wide separation between the ultrasonic sensor and the amplifier, meaning that it is not easy to build an ideal PAE system that would be unaffected by EMI noise. With the intention of expediting the progress of related research, in this study, we investigated the feasibility of deep-learning-based EMI noise removal involved in PAE image processing. In particular, we selected four fully convolutional neural network architectures, U-Net, Segnet, FCN-16s, and FCN-8s, and observed that a modified U-Net architecture outperformed the other architectures in the EMI noise removal. Classical filter methods were also compared to confirm the superiority of the deep-learning-based approach. Still, it was by the U-Net architecture that we were able to successfully produce a denoised 3D vasculature map that could even depict the mesh-like capillary networks distributed in the wall of a rat colorectum. As the development of a low-cost laser diode or LED-based photoacoustic tomography (PAT) system is now emerging as one of the important topics in PAT, we expect that the presented AI strategy for the removal of EMI noise could be broadly applicable to many areas of PAT, in which the ability to apply a hardware-based prevention method is limited and thus EMI noise appears more prominently due to poor SNR.

Intra-instrument channel workable, optical-resolution photoacoustic and ultrasonic mini-probe system for gastrointestinal endoscopy.

There has been a long-standing expectation that the optical-resolution embodiment of photoacoustic tomography could have a substantial impact on gastrointestinal endoscopy by enabling microscopic visualization of the vasculature based on the endogenous contrast mechanism. Although multiple studies have demonstrated the in vivo imaging capability of a developed imaging device over the last decade, the implementation of such an endoscopic system that can be applied immediately when necessary via the instrument channel of a video endoscope has been a challenge. In this study, we developed a 3.38-mm diameter catheter-based, integrated optical-resolution photoacoustic and ultrasonic mini-probe system and successfully demonstrated its intra-instrument channel workability for the standard 3.7-mm diameter instrument channel of a clinical video endoscope based on a swine model. Through the instrument channel, we acquired the first in vivo dual-mode photoacoustic and ultrasonic endoscopic images from the esophagogastric junction of a swine. Further, in a rat colorectum in vivo imaging experiment, we visualized hierarchically developed mesh-like capillary networks with a hole size as small as ~50 µm, which suggests the potential level of image details that could be photoacoustically provided in clinical settings in the future.

Pragmatic trial comparing routine versus no routine functional testing in high-risk patients who underwent percutaneous coronary intervention: Rationale and design of POST-PCI trial.

BACKGROUND: Although the need to detect restenosis has diminished in the contemporary practice of percutaneous coronary intervention (PCI) with drug-eluting stents (DES), the surveillance of ischemia owing to restenosis or disease progression deserves attention in high-risk PCI settings. It is unknown whether follow-up strategy of routine noninvasive functional testing potentially reduces the risk of major cardiovascular events in high-risk PCI patients. METHODS: The POST-PCI study is an investigator-initiated, multicenter, prospective randomized trial comparing the effectiveness of two follow-up strategies in patients with high-risk anatomic or clinical characteristics who underwent PCI. Study participants were randomly assigned to either (1) the routine noninvasive stress testing (exercise electrocardiography, nuclear stress imaging, or stress echocardiography) at 12 months post-PCI or (2) the standard-care without routine testing. In the routine stress testing group, depending on the testing results, all clinical decisions regarding subsequent diagnostic or therapeutic procedures were at the treating physician's discretion. The primary endpoint was a composite outcome of death from any causes, myocardial infarction, or hospitalization for unstable angina at 2 years post-PCI. RESULTS: More than 1700 high-risk PCI patients have been randomized over 2.0 years at 11 major cardiac centers in Korea. CONCLUSION: This pragmatic POST-PCI trial will provide valuable clinical evidence on the effectiveness of follow-up strategy of routine noninvasive stress testing in high-risk PCI patients.

The impact of a dose of the angiotensin receptor blocker valsartan on post-myocardial infarction ventricular remodelling.

AIMS: Although clinical guidelines advocate the use of the highest tolerated dose of angiotensin-converting enzyme inhibitors or angiotensin receptor blockers after acute myocardial infarction (MI), the optimal dosing or the risk-benefit profile of different doses have not been fully identified. METHODS AND RESULTS: In this multicentre trial, 495 Korean patients with acute ST segment elevation MI and subnormal left ventricular (LV) ejection fraction (<50%) were randomly allocated (2:1) to receive maximal tolerated dose of valsartan (titrated up to 320 mg/day, n = 333) or low-dose valsartan (80 mg/day, n = 162) treatment. The primary objective was to assess the changes in echocardiographic parameters of LV remodelling from baseline to 12 months after discharge. After treatment, end-diastolic LV volume (LVEDV) decreased significantly in the low-dose group, but the difference in LVEDV changes was insignificant between the maximal-tolerated-dose and low-dose groups. End-systolic LV volume decreased significantly in both groups, to a similar degree between groups. LV ejection fraction rose significantly in both study groups, to a similar degree. Changes in plasma levels of neurohormones were also comparable between the two groups. Drug-related adverse effects occurred more frequently in the maximal-tolerated-dose group than in the low-dose group (7.96 vs. 0.69%, P < 0.001). CONCLUSIONS: In the present study, treatment with the maximal tolerated dose of valsartan did not exhibit a superior effect on post-MI LV remodelling compared with low-dose treatment and was associated with a greater frequency of adverse effect in Korean patients. Further study with a sufficient number of cases and statistical power is warranted to verify the findings of the present study.

Successful extracorporeal life support in sudden cardiac arrest due to coronary anomaly.

Extracorporeal life support (ECLS) has recently been reported to have a survival benefit in patients with cardiac arrest. It is now used widely as a lifesaving modality. Here, we describe a case of sudden cardiac arrest (SCA) in a young athlete with an anomalous origin of the right coronary artery from the left coronary sinus. Resuscitation was successful using ECLS before curative bypass surgery. We highlight the efficacy of ECLS for a patient with SCA caused by a rare, unexpected aetiology. In conclusion, ECLS was a lifesaving modality for SCA due to an anomalous coronary artery in this young patient.

A Randomized, Double-blind, Candesartan-controlled, Parallel Group Comparison Clinical Trial to Evaluate the Antihypertensive Efficacy and Safety of Fimasartan in Patients with Mild to Moderate Essential Hypertension.

PURPOSE: A new antihypertensive drug that selectively blocks angiotensin II receptor type 1, fimasartan, has a potent and rapidly acting antihypertensive effect. We investigated the antihypertensive effects of fimasartan 60 and 120 mg and its safety in comparison to 8 mg of candesartan. METHODS: This clinical trial is a multicenter, randomized, double-blind, active comparator, and parallel group study. Three hundred sixty-two individuals were screened, and 290 patients aged 19 to 75 years with mild to moderate hypertension (diastolic blood pressure [DBP], 90-110 mm Hg) were randomly assigned to 60 to 120 mg/d of fimasartan or 8 mg/d of candesartan after a 2-week placebo run-in period. Treatments were administered for 12 weeks without dosage adjustment. The primary end point was the differences in DBP changes at week 12. FINDINGS: After 12 weeks of treatment, DBP and systolic blood pressure (SBP) decreased significantly in all 3 groups. The decrease in DBP at week 12 was larger but not statistically significant in the fimasartan 60 mg compared with the candesartan 8 mg group with a mean (SD) difference of 1.72 (8.32) mm Hg (95% CI, -0.71 to 4.15 mm Hg; P = 0.17). The lower margin of the CI (-0.71 mm Hg) exceeded the noninferiority margin (-3.5 mm Hg). The DBP-lowering effect of fimasartan 120 mg was also nonsignificantly larger than candesartan 8 mg (difference, 1.58 [8.27] mm Hg; P = 0.20). The decrease in SBP was also nonsignificantly larger in the fimasartan 60 mg group compared with the candesartan 8 mg group (difference, 3.50 [12.63] mm Hg; P = .06). The SBP-lowering effect of fimasartan 120 mg was statistically larger than candesartan 8 mg (difference, 4.98 [13.99] mm Hg; P = .02). Response rate (DBP <90 mm Hg or DBP lowering >10 mm Hg at week 12) was also nonsignificantly greater in both fimasartan groups (Fimasartan 60 mg, 81%; fimasartan 120 mg, 72%; candesartan 8 mg, 71%). The safety profile of the fimasartan 60 mg and 120 mg was similar to candesartan 8 mg, with a slightly higher, but statistically not significant, incidence of hepatic enzyme elevation in fimasartan 120 mg. IMPLICATIONS: The antihypertensive effect of fimasartan, a newly available angiotensin II receptor type 1 blocker, is comparable, although not superior, to candesartan with a good safety profile. ClinicalTrials.gov identifier: NCT01135212.

A Randomized, Multicenter, Double-blind, Placebo-controlled, 3 × 3 Factorial Design, Phase II Study to Evaluate the Efficacy and Safety of the Combination of Fimasartan/Amlodipine in Patients With Essential Hypertension.

PURPOSE: The objective of this study was to evaluate the efficacy and safety of a fimasartan/amlodipine combination in patients with hypertension and to determine the optimal composition for a future single-pill combination formulation. METHODS: This Phase II study was conducted by using a randomized, multicenter, double-blind, placebo-controlled, 3 × 3 factorial design. After a 2-week placebo run-in period, eligible hypertensive patients (with a sitting diastolic blood pressure [SiDBP] between 90 and 114 mm Hg) were randomized to treatment. They received single or combined administration of fimasartan at 3 doses (0, 30, and 60 mg) and amlodipine at 3 doses (0, 5, and 10 mg) for 8 weeks. The primary efficacy end point was the change in SiDBP from baseline and at week 8; secondary end points included the change in SiDBP from baseline and at week 4 and the changes in sitting systolic blood pressure from baseline and at weeks 4 and 8. Treatment-emergent adverse events (AEs) were also assessed. FINDINGS: 420 Korean patients with mild to moderate hypertension were randomly allocated to the 9 groups. Mean (SD) SiDBP changes in each group after 8 weeks were as follows: placebo, -6.0 (8.5) mm Hg; amlodipine 5 mg, -10.6 (9.2) mm Hg; amlodipine 10 mg, -15.9 (7.2) mm Hg; fimasartan 30 mg, -10.1 (9.1) mm Hg; fimasartan 60 mg, -13.0 (10.0) mm Hg; fimasartan 30 mg/amlodipine 5 mg, -16.2 (8.5) mm Hg; fimasartan 30 mg/amlodipine 10 mg, -19.5 (7.5) mm Hg; fimasartan 60 mg/amlodipine 5 mg, -16.6 (6.9) mm Hg; and fimasartan 60 mg/amlodipine 10 mg, -21.5 (8.3) mm Hg. All treatment groups produced significantly greater reductions in blood pressure compared with the placebo group. In addition, all combination treatment groups had superior reductions in blood pressure compared with the monotherapy groups. In the combination treatment groups, doubling fimasartan dose in the given dose of amlodipine did not show further BP reduction, whereas doubling amlodipine dose showed significantly further BP reduction in the given dose of fimasartan. During the study period, 75 (17.9%) of 419 patients experienced 110 AEs. Ninety-five AEs were mild, 9 were moderate, and 6 were severe in intensity. Eight patients discontinued the study due to AEs. There was no significant difference in incidence of AEs among groups (P = 0.0884). The most common AE was headache (12 patients [2.9%]), followed by dizziness (11 patients [2.6%]) and elevated blood creatine phosphokinase levels (6 patients [1.4%]). IMPLICATIONS: Fimasartan combined with amlodipine produced superior blood pressure reductions and low levels of AEs compared with either monotherapy. Therefore, a single-pill combination with fimasartan 60 mg/amlodipine 10 mg will be developed. ClinicalTrials.gov: NCT01518998.

A prospective, randomized comparison of promus everolimus-eluting and TAXUS Liberte paclitaxel-eluting stent systems in patients with coronary artery disease eligible for percutaneous coronary intervention: the PROMISE study.

We aimed comparing two-year clinical outcomes of the Everolimus-Eluting Promus and Paclitaxel-Eluting TAXUS Liberte stents used in routine clinical practice. Patients with objective evidence of ischemia and coronary artery disease eligible for PCI were prospectively randomized to everolimus-eluting stent (EES) or paclitaxel-eluting stent (PES) groups. The primary end-point was ischemia-driven target vessel revascularization (TVR) at 2 yr after intervention, and the secondary end-point was a major adverse cardiac event (MACE), such as death, myocardial infarction (MI), target lesion revascularization (TLR), TVR or stent thrombosis. A total of 850 patients with 1,039 lesions was randomized to the EES (n=425) and PES (n=425) groups. Ischemic-driven TVR at 2 yr was 3.8% in the PES and 1.2% in the EES group (P for non-inferiority=0.021). MACE rates were significantly different; 5.6% in PES and 2.5% in EES (P = 0.027). Rates of MI (0.8% in PES vs 0.2% in EES, P = 0.308), all deaths (1.5% in PES vs 1.2% in EES, P = 0.739) and stent thrombosis (0.3% in PES vs 0.7% in EES, P = 0.325) were similar. The clinical outcomes of EES are superior to PES, mainly due to a reduction in the rate of ischemia-driven TVR.

Beneficial Effect of Efonidipine, an L- and T-Type Dual Calcium Channel Blocker, on Heart Rate and Blood Pressure in Patients With Mild-to-Moderate Essential Hypertension.

BACKGROUND AND OBJECTIVES: Efonidipine hydrochloride, an L- and T-type dual calcium channel blocker, is suggested to have a heart rate (HR)-slowing action in addition to a blood pressure (BP)-lowering effect. The aim of this study was to determine the effect of efonidipine on HR and BP in patients with mild-to-moderate hypertension. SUBJECTS AND METHODS: In a multi-center, prospective, open-labeled, single-armed study, we enrolled 53 patients who had mild-to-moderate hypertension {sitting diastolic BP (SiDBP) 90-110 mmHg}. After a 2-week washout, eligible patients were treated with efonidipine (40 mg once daily for 12 weeks). The primary end point was the change in HR from baseline to week 12. The secondary end-point included the change in trough sitting BP and 24-hour mean BP between baseline and week 12. Laboratory and clinical adverse events were monitored at each study visit (4, 8, and 12 weeks). RESULTS: Fifty-two patients were included in the intention-to-treat analysis. After 12 weeks of treatment with efonidipine, the resting HR decreased significantly from baseline to week 12 {from 81.5±5.3 to 71.8±9.9 beats/minute (difference, -9.9±9.0 beats/minute), p<0.0001}. The trough BP {sitting systolic blood pressure (SiSBP) and SiDBP} and 24-hour mean BP also decreased significantly (SiSBP: from 144.6±8.2 to 132.9±13.5 mmHg, p<0.0001; SiDBP: from 96.9±5.4 to 88.3±8.6 mmHg, p<0.0001, 24-hour mean systolic BP: from 140.4±13.5 to 133.8±11.6 mmHg, p<0.0001; 24-hour mean diastolic BP: from 91.7±8.7 to 87.5±9.5 mmHg, p<0.0001). CONCLUSION: Efonidipine was effective in controlling both HR and BP in patients with mild-to-moderate hypertension.

Polarization of completely coherent random electromagnetic beams.

It is shown that the spectral degree of polarization rho(r, omega) of a fluctuating electromagnetic beam which is completely coherent throughout a domain D is necessarily the same at every point in D. It can take on any value in the range 0 < or = rho < or = 1. In particular, the fully coherent beam can be completely polarized or completely unpolarized throughout D.