One-year safety and effectiveness of the Agent paclitaxel-coated balloon for the treatment of small vessel disease and in-stent restenosis

The Agent device consists of a semi-compliant balloon catheter, which is coated with a therapeutic low-dose formulation of paclitaxel (2 µg/mm2) blended with an inactive excipient acetyl-tri-n-butyl citrate (ATBC). AGENT Japan SV is a randomized controlled study that enrolled 150 patients from 14 Japanese sites treated with Agent or SeQuent Please paclitaxel-coated balloon. This study also includes a single-arm substudy evaluating the safety and effectiveness of Agent in patients with in-stent restenosis (ISR). Patients with a single de novo native lesion (lesion length ≤ 28 mm and reference diameter ≥ 2.00 to  < 3.00 mm) were randomized 2:1 to receive either Agent (n = 101) or SeQuent Please (n = 49). The ISR substudy enrolled 30 patients with lesion length ≤ 28 mm and reference diameter ≥ 2.00 to  ≤ 4.00 mm. In the SV RCT, target lesion failure (TLF) at 1 year occurred in four patients treated with Agent (4.0%) versus one patient with SeQuent Please (2.0%; P = 1.00). None of the patients in either treatment arm died. There were no significant differences in the rates of myocardial infarction, target lesion revascularization and target lesion thrombosis through 1 year. In the ISR substudy, the 1-year rates of TLF and target lesion thrombosis were 6.7% and 0.0%, respectively. These data support the safety and effectiveness of the Agent paclitaxel-coated balloon in patients with small vessels and ISR.

First randomised controlled trial comparing the sirolimus-eluting bioadaptor with the zotarolimus-eluting drug-eluting stent in patients with de novo coronary artery lesions: 12-month clinical and imaging data from the multi-centre, international, BIODAPTOR-RCT

Background

The DynamX™ bioadaptor is the first coronary implant technology with a unique mechanism of unlocking the bioadaptor frame after polymer resorption over 6 months, uncaging the vessel while maintaining a dynamic support to the vessel. It aims to achieve the acute performance of drug-eluting stents (DES) with the advantages of restoration of vessel function.

Methods

This international, single blinded, randomised controlled (1:1) trial compared a sirolimus-eluting bioadaptor with a contemporary zotarolimus-eluting stent (DES) in 34 hospitals in Europe, Japan and New Zealand. Patients with de novo coronary lesions and absence of acute myocardial infarction were enrolled from January 2021 to Feburary 2022. The implantation of the bioadaptor followed the standards of DES. An imaging subset of 100 patients had angiographic and intravascular ultrasound assessments, and 20 patients additionally optical coherence tomography. Data collection will continue through 5 years, we herein report 12-month data based on an intention-to-treat population. This trial is registered at ClinicalTrials.gov (NCT04192747).

Findings

445 patients were randomised between January 2021 and February 2022. Device, lesion and procedural success rates, and acute gain were similar amongst the groups. The primary endpoint, 12-month target lesion failure, was 1.8% [95% CI: 0.5; 4.6] (n = 4) versus 2.8% [95% CI: 1.0; 6.0] (n = 6), pnon-inferiority < 0.001 for the bioadaptor and the DES, respectively (Δ-1.0% [95% CI: -3.3; 1.4]). One definite or probable device thrombosis occurred in each group. The 12-month imaging endpoints showed superior effectiveness of the bioadaptor such as in-device late lumen loss (0.09 mm [SD 0.34] versus 0.25 mm [SD 0.39], p = 0.04), and restored compliance and cyclic pulsatility (%mid in-device lumen area change of 7.5% versus 2.7%, p < 0.001).

Interpretation

This is the first randomised controlled trial comparing the novel bioadaptor technology against a contemporary DES. The bioadaptor demonstrated similar acute performance and 12-month clinical outcomes, and superior imaging endpoints including restoration of vessel function.

Funding

The study was funded by Elixir Medical.

Diagnosis and Prognostic Value of the Underlying Cause of Acute Coronary Syndrome in Optical Coherence Tomography-Guided Emergency Percutaneous Coronary Intervention

Background The prognostic impact of optical coherence tomography-diagnosed culprit lesion morphology in acute coronary syndrome (ACS) has not been systematically examined in real-world settings. Methods and Results This investigator-initiated, prospective, multicenter, observational study was conducted at 22 Japanese hospitals to identify the prevalence of underlying ACS causes (plaque rupture [PR], plaque erosion [PE], and calcified nodules [CN]) and their impact on clinical outcomes. Patients with ACS diagnosed within 24 hours of symptom onset undergoing emergency percutaneous coronary intervention were enrolled. Optical coherence tomography-guided percutaneous coronary intervention recipients were assessed for underlying ACS causes and followed up for major adverse cardiac events (cardiovascular death, myocardial infarction, heart failure, or ischemia-driven revascularization) at 1 year. Of 1702 patients with ACS, 702 (40.7%) underwent optical coherence tomography-guided percutaneous coronary intervention for analysis. PR, PE, and CN prevalence was 59.1%, 25.6%, and 4.0%, respectively. One-year major adverse cardiac events occurred most frequently in patients with CN (32.1%), followed by PR (12.4%) and PE (6.2%) (log-rank P<0.0001), primarily driven by increased cardiovascular death (CN, 25.0%; PR, 0.7%; PE, 1.1%; log-rank P<0.0001) and heart failure trend (CN, 7.1%; PR, 6.8%; PE, 2.2%; log-rank P<0.075). On multivariate Cox regression analysis, the underlying ACS cause was associated with 1-year major adverse cardiac events (CN [hazard ratio (HR), 4.49 [95% CI, 1.35-14.89], P=0.014]; PR (HR, 2.18 [95% CI, 1.05-4.53], P=0.036]; PE as reference). Conclusions Despite being the least common, CN was a clinically significant underlying ACS cause, associated with the highest future major adverse cardiac events risk, followed by PR and PE. Future studies should evaluate the possibility of ACS underlying cause-based optical coherence tomography-guided optimization.

Long-term outcome and risk factors associated with events in patients with atrial fibrillation treated with oral anticoagulants: The ASSAF-K registry

BACKGROUND

Oral anticoagulant therapy for atrial fibrillation (AF) has changed dramatically. Direct oral anticoagulant (DOAC) therapy is administered by general practitioners and specialists. However, the beneficial long-term effects and safety of DOACs have not been well investigated in real-world clinical practice.

METHODS

The ASSAF-K (a study of the safety and efficacy of OAC therapy in the treatment of AF in Kanagawa), a prospective, multi-center, observational study, was conducted to clarify patient characteristics, status of OAC treatment, long-term outcomes, and adverse events, including cerebrovascular disease, bleeding, and death.

RESULTS

A total of 4014 patients were enrolled (hospital: 2500 cases; clinic: 1514 cases). The number of patients in the final dataset was 3367 (mean age, 72.6 ± 10.0 years; males, 66.3 %). CHA₂DS₂-VASc and HAS-BLED scores were 3.0 ± 1.6 and 2.2 ± 1.0, respectively. The risk factors of the primary composite outcome (all-cause death, serious bleeding events, cerebral hemorrhage, and stroke) were higher age, lower body mass index, lower diastolic blood pressure, lower creatine clearance, history of heart failure, history of stroke, and medication of anti-platelet agents. The event-free rates of the primary composite outcome with DOACs, warfarin, and without OACs were 92.7 %, 88.0 %, and 87.4 %, respectively. The event rate of DOACs was significantly lower than that of warfarin [HR 0.63 (95 % CI 0.48-0.81)], and similar results were observed after adjustment for AF stroke risk score [HR 0.70 (95 % CI 0.54-0.90)]. Serious bleeding events tended to occur less frequently with DOACs compared with warfarin [unadjusted HR 0.53 (95 % CI 0.31-0.91), adjusted HR 0.61 (95 % CI 0.33-1.11)].

CONCLUSIONS

This multi-center registry demonstrated the long-term outcome in patients with AF treated with and without OACs and suggests that DOAC therapy is safe and beneficial in hospitals and clinics.

Radial versus femoral access in patients undergoing primary percutaneous coronary intervention for ST-elevation myocardial infarction: A propensity-matched analysis from real-world data of the K-ACTIVE registry

BACKGROUND

The access site for primary percutaneous coronary intervention (PCI) for patients with ST-elevation myocardial infarction (STEMI) recently shifted from femoral to radial. However, few real-world data on Japanese patients exist.

METHODS

To elucidate the clinical selection and impact of the access site in STEMI patients, we analyzed a Japanese observational prospective multicenter registry of acute myocardial infarction (K-ACTIVE: Kanagawa ACuTe cardIoVascular rEgistry) in 2015 to 2021. Data were analyzed in the entire population and a propensity score-matched population adjusted for confounding factors. Major adverse cardiac event (MACE) was defined as cardiovascular death, non-fatal myocardial infarction, and non-fatal stroke. Bleeding Academic Research Consortium (BARC) type 3 or 5 was used to assess bleeding events. MACE plus BARC type 3 or 5 bleeding were considered composite events. Clinical outcomes were followed for 30 days.

RESULTS

The 6802 STEMI patients included 4786 patients with radial access (70.3 %) and 2016 with femoral access (29.7 %). Femoral access tended to be selected for more severe conditions than radial access. The median door-to-device time in the radial access group was significantly shorter than the femoral access group in the entire population (75 min versus 79 min, p < 0.01). After propensity score matching (each group, n = 1208), the incidence of MACE tended to be lower in the radial access group [risk ratio (RR) 0.83, 95 % confidence interval (CI) 0.63-1.09, p = 0.17]. The incidence of BARC 3 or 5 bleeding was significantly less in the radial access group (RR 0.47, 95%CI 0.23-0.97, p = 0.04). The incidence of composite events was significantly less in the radial access group (RR 0.74, 95%CI 0.57-0.96, p = 0.02).

CONCLUSION

In STEMI patients undergoing primary PCI, in comparison to femoral access, radial access reduced composite events in the entire population and the matched population, through a reduction in MACE and BARC 3 or 5 bleeding.

Drug-Coated Balloon for the Treatment of Small Vessel Coronary Artery Disease - A Randomized Non-Inferiority Trial

BACKGROUND

Drug-coated balloons (DCB) have shown promising results for the treatment of in-stent restenosis (ISR) and small vessel disease (SVD). However, data comparing the treatment efficacy of different DCBs are limited.Methods and Results: AGENT Japan is a prospective randomized controlled trial that compares the Agent balloon coated with a low-dose formulation of paclitaxel (2 μg/mm²) to the SeQuent Please paclitaxel-coated balloon (3 μg/mm²) for the treatment of SVD. Patients with target lesion length ≤28 mm and reference diameter between ≥2.00 and <3.00 mm were randomized 2 : 1 for treatment with Agent (n=101) or SeQuent Please (n=49). This trial also includes a separate single-arm substudy evaluating the clinical safety and effectiveness of Agent in patients with ISR. The primary endpoint of 6-month target lesion failure (TLF) was observed in 3.0% of Agent and 0.0% of SeQuent Please patients (difference=3.0%; 97.5% upper confidence bound [UCB]=9.57%, which is less than the prespecified margin of 13.2%; P_{non-inferiority}=0.0012). There were no deaths or thrombosis, and angiographic and quality-of-life outcomes were comparable between groups. The AGENT Japan ISR substudy (n=30) primary endpoint was met because the one-sided 97.5% UCB for 6-month TLF (3.3%) was significantly less than the study success criterion of 15.1% (97.5% UCB=9.8%; P<0.0001).

CONCLUSIONS

Data from this study demonstrate good clinical outcomes with the Agent DCB when used to treat patients with SVD or ISR.

Rationale and design of the TACTICS registry: Optical coherence tomography guided primary percutaneous coronary intervention for patients with acute coronary syndrome

BACKGROUND

Recent retrospective investigations have suggested that optical coherence tomography (OCT) enables the diagnosis of underlying acute coronary syndrome (ACS) causes such as plaque rupture, plaque erosion, and calcified nodule. The relationships of these etiologies with clinical outcomes, and the clinical utility of OCT-guided primary percutaneous coronary intervention (PCI) are not systematically studied in real-world ACS treatment settings.

METHODS

The TACTICS registry is an investigator-initiated, prospective, multicenter, observational study to be conducted at 21 hospitals in Japan. A total of 700 patients with ACS (symptom onset within 24 h) undergoing OCT-guided primary PCI will be enrolled. The primary endpoint of the study is to identify the underlying causes of ACS using OCT-defined morphological assessment of the culprit lesion. The key secondary clinical endpoints are hazard ratios of the composite of cardiovascular death, non-fatal myocardial infarction, heart failure, or ischemia-driven revascularization in patients with underlying etiologies at the 12- and 24-month follow-ups. The feasibility of OCT-guided primary PCI for ACS will be assessed by the achievement rates of optimal post-procedural results and safety endpoints.

CONCLUSION

The TACTICS registry will provide an overview of the underlying causes of ACS using OCT, and will reveal any difference in clinical outcomes depending on the underlying causes. The registry will also inform on the feasibility of OCT-guided primary PCI for patients with ACS.

A Japanese Dose of Prasugrel versus a Standard Dose of Clopidogrel in Patients with Acute Myocardial Infarction from the K-ACTIVE Registry

BACKGROUND

Dual antiplatelet therapy (DAPT) with aspirin plus P2Y12 inhibitor is used as a standard therapy for patients with acute myocardial infarction (AMI) treated with drug-eluting stents (DESs). In Japan, clopidogrel was the major P2Y12 inhibitor used for a decade until the new P2Y12 inhibitor, prasugrel, was introduced. Based on clinical studies considering Japanese features, the set dose for prasugrel was reduced to 20 mg as a loading dose (LD) and 3.75 mg as a maintenance dose (MD); these values are 60 and 10 mg, respectively, globally. Despite this dose discrepancy, little real-world clinical data regarding its efficacy and safety exist.

METHODS

From the K-ACTIVE registry, based on the DAPT regimen, patients were divided into a prasugrel group and a clopidogrel group. The ischemic event was a composite of cardiovascular death, non-fatal MI, and non-fatal stroke. The bleeding event was type 3 or 5 bleeding based on the Bleeding Academic Research Consortium (BARC) criteria.

RESULTS

Substantially more patients were prescribed prasugrel (n = 2786) than clopidogrel (n = 890). Clopidogrel tended to be selected over prasugrel in older patients with numerous comorbidities. Before adjustments were made, the cumulative incidence of ischemic events at 1 year was significantly greater in the clopidogrel group than in the prasugrel group (p = 0.007), while the cumulative incidence of bleeding events at 1 year was comparable between the groups (p = 0.131). After adjustments were made for the age, sex, body weight, creatine level, type of AMI, history of MI, approach site, oral anticoagulation therapy, presence of multivessel disease, Killip classification, and presence of intra-aortic balloon pumping, both ischemic and bleeding events became comparable between the groups.

CONCLUSION

A Japanese dose of prasugrel was commonly used in AMI patients in the real-world database. Both the prasugrel and clopidogrel groups showed comparable rates of 1 year ischemic and bleeding events.

The impact of pre-hospital 12-lead electrocardiogram and first contact by cardiologist in patients with ST-elevation myocardial infarction in Kanagawa, Japan

Background pre-hospital 12-lead electrocardiogram (ECG) by emergency medical service (EMS) personnel at the site of first medical contact (FMC) and the physician of first contact both play important roles in managing patients with ST-elevation myocardial infarction (STEMI). However, in Japan, pre-hospital 12-lead ECG is not routinely performed by EMS personnel at the site of FMC and the physician of first contact is not always a cardiologist. Methods from October 2015 to October 2019, 2035 consecutive STEMI patients transported from the field by ambulance were analyzed from the K-ACTIVE registry. Based on the presence (+) or absence (-) of pre-hospital 12-lead ECG / first contact by cardiologist, patients were divided into 4 groups (+/+, +/-, -/+, -/-). Patient characteristics, FMC to door time, door to device time and in-hospital mortality were compared. Results the numbers of patients in each group were as follows (+/+, n = 987; +/-, n = 211; -/+, n = 610; -/-, n = 227). For patient characteristics, there were significant differences in the prevalence of dyslipidemia and the presence of chest pain. The FMC to door time was similar (median value, +/+, 24 min; +/-, 25 min; -/+, 24 min; -/-, 24 min; p = 0.23). The door to device time was the shortest in the +/+ group (median value, +/+, 65 min; +/-, 80 min; -/+, 69 min; -/-, 88 min; p < 0.0001). Crude in-hospital mortality was the highest in the -/- group (+/+, 3.9%; +/-, 2.4%; -/+, 5.8%; -/-, 11.9%; p < 0.0001). After adjustment for age and sex, the adjusted odds ratios for in-hospital mortality were as follows [odds ratio (with 95% confidence interval) +/+, 0.33 [0.19-0.57]; +/-, 0.19 [0.07-0.52]; -/+, 0.49 [0.29-0.86]; -/-, 1 [reference)]. Conclusion pre-hospital 12-lead ECG and the physician of first contact had a significant impact on the door to device time and in-hospital mortality. Continuous efforts should be made to improve acute management of STEMI.

Clinical significance of prehospital 12-lead electrocardiography in patients with ST-segment elevation myocardial infarction presenting with syncope: from a multicenter observational registry (K-ACTIVE study)

Patients with acute myocardial infarction (AMI) presenting with syncope have poor clinical outcomes partly due to a delay in the diagnosis. Although the impact of prehospital 12-lead electrocardiography (PHECG) on the reduction of first medical contact (FMC)-to-device time and subsequent adverse clinical events in patients with AMI has been demonstrated, the impact of PHECG for the patients presenting with syncope remains to be elucidated. This study aimed to explore the impact of PHECG on 30-day mortality in patients with ST-segment elevation myocardial infarction (STEMI) presenting with syncope. From a cohort of multi-center registry [Kanagawa-ACuTe cardIoVascular rEgistry (K-ACTIVE)], a total of 90 consecutive patients with STEMI presenting with syncope were included. The 30-day mortality were compared between patients with PHECG (PHECG group, n = 25) and those without PHECG (non-PHECG group, n = 65). There was no significant difference in the baseline clinical characteristics between the 2 groups. FMC-to-device time was significantly shorter in the PHECG group than in the non-PHECG group (122 [86, 128] vs. 131 [102, 153] min, p = 0.03) due to the shorter door-to-device time. Thirty-day mortality was significantly lower in the PHECG group than in the non-PHECG group (16.0 vs. 44.6%, p = 0.03). In conclusion, PHECG was associated with shorter FMC-to-device time and lower 30-day mortality in patients with STEMI presenting with syncope.

Atrial Fibrillation is related with higher in-hospital morality in acute myocardial infarction (AMI) patients from K-ACTIVE registry

Background

The prognostic significance of atrial fibrillation (AF) on in-hospital mortality in acute myocardial infarction (AMI) patients is not fully understood in Japanese patients.

Methods

To elucidate the clinical significance of AF on in-hospital mortality in AMI patients, we analyzed the Japanese observational prospective multicenter registry of acute myocardial infarction (K-ACTIVE: Kanagawa ACuTe cardio Vacular rEgistry), which spans October 2016 to December 2019.

Results

A total of 3482 patients included 336 patients with AF and 3146 patients with sinus rhythm. Table 1 shows patient baseline characteristics. Patients with AF were significantly older than those with sinus rhythm (75 vs 67, P&lt;0.0001). Prevalence of hypertension and hemodialysis were significantly greater in patients with AF than patients with sinus rhythm while prevalence of dyslipidemia and smoking were significantly less in patients with AF than patients with sinus rhythm. Table 2 shows characteristics of AMI. There were no significant difference in prevalence of STEMI, area of MI, Peak CK/CK-MB and prevalence of multivessel disease. However, patients with AF showed lower systolic blood pressure, faster heart rate, worse Killip category, greater prevalence of OHCA. Need of mechanical support including IABP/ECMO were greater in patients with AF than patients with sinus rhythm. In-hospital mortality was significantly higher in patients with AF than in patients with sinus rhythm (Figure, 10.4% versus 5.2%, P=0.0005). This trend didn't change even after adjustment with age and sex (Odds ratio 1.6 95% confidence interval 1.1–2.4, P=0.02).

Conclusion

AF was associated with higher in-hospital mortality in Japanese AMI patients.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): This work was supported by JSPS KAKENHI Grant Number JP15K09101.

A novel risk stratification system "Angiographic GRACE Score" for predicting in-hospital mortality of patients with acute myocardial infarction: Data from the K-ACTIVE Registry

BACKGROUND

The Global Registry of Acute Coronary Events (GRACE) score is the most accurate risk assessment system for acute myocardial infarction (AMI), which was proposed in Western countries. However, it is unclear whether GRACE score is applicable to the present Japanese patients with a high prevalence of emergent percutaneous coronary intervention (PCI) and vasospasm. This study aimed to clarify the usefulness of GRACE risk score for risk stratification of Japanese AMI patients treated with early PCI and to evaluate a novel risk stratification system, "angiographic GRACE score," which is the GRACE risk score adjusted by the information of the culprit coronary artery and its flow at pre- and post-PCI, to improve its predicting availability.

METHODS

The subjects were 1817 AMI patients who underwent PCI within 24 h of onset between October 2015 and August 2017 and were registered in Kanagawa Acute Cardiovascular (K-ACTIVE) Registry via survey form. The association between the clinical parameters and in-hospital mortality was investigated.

RESULTS

A total of 79 (4.3%) in-hospital deaths were identified. The C-statistics for the in-hospital mortality of the GRACE score was 0.86, which was higher than that of the other conventional risk factors, including age (0.65), systolic blood pressure (0.70), heart rate (0.62), Killip classification (0.77), and serum levels of creatinine (0.68) and peak creatine kinase (0.74). The angiographic GRACE score improved the C-statistics from 0.86 of the original GRACE score to 0.89 (p < 0.05). In the setting of the cut-off value at 200, in-hospital mortality in the patients with the angiographic GRACE score <200 was 0.6%, which was relatively lower than those with ≥200, 9.4%.

CONCLUSIONS

The GRACE score is a useful predictor of in-hospital mortality among Japanese AMI patients in the PCI era. Moreover, the angiographic GRACE score could improve the predicting availability.

P17 In-hospital mortality and clinical features of Japanese patients with acute myocardial infarction diagnosed by universal definition in real world from kanagawa-acute cardiovascular registry (K-ACTIVE)

Background

Cardiac troponin (cTn) has been used as the preferred biomarker of myocardial injury for diagnosis of acute myocardial infraction (AMI) by universal definition. A large number of patients formerly classified by creatine kinase (CK) as unstable angina with the WHO criteria in Japan are now diagnosed by cTn as non-ST elevation myocardial infarction (NSTEMI). In this report, we aimed to understand its prevalence and clinical features of AMI diagnosed by using universal definition and the WHO criterial in real world. 

Method

This registry is a cross-sectional study of 53 facilities in Kanagawa prefecture of Japan. 4372 AMI patients were enrolled who received primary percutaneous coronary intervention (PCI) between October 1, 2015 and January 29, 2019. Patients were divided into 3 groups, 3268 patients with ST elevation myocardial infarction (STEMI), 628 patients with NSTEMI patients who satisfied the WHO criteria with CK elevation beyond twice upper limit of normal (NSTEMI + CK), and 476 patients with NSTEMI who didn’t satisfy the WHO criteria without CK elevation (NSTEMI-CK).

Result

Baseline clinical characteristics of the study patients are shown in Table 1. In-hospital mortality was significantly lower in patients with NSTEMI-CK (1.9%) than in STEMI (6.0%, P &lt; 0.001) and NSTEMI + CK (5.3%, P &lt; 0.004) (Figure 1). Kaplan-Meier analyses for 0-30 days of cardiac death are shown in Figure 2. From day 0, the Kaplan-Meier curves began to diverge in favor of NSTEMI-CK for up to 30 days.

Conclusion

AMI patients showed distinct clinical features depends on the type. We should be aware of the difference for the diagnosis of AMI by using universal definitions.

Table 1. 　 STEMI (n = 3268) NSTEMI + CK (n = 628) NSTEMI-CK (n = 476) STEMI vs NSTEMI + CK P value STEMI vs NSTEMI-CK P value NSTEMI + CK vs NSTEMI-CK P value Age(years) 68(59-77) 69(61-78) 70(61-79) 　 　 　 Male 76% 77% 75% 0.54 0.74 0.47 Concomitant diseases 　 　 　 　 　 　 Hypertention 65.4% 70.5% 69.3% 0.013 0.097 0.65 Diabetes 33.5% 36.5% 37.3% 0.15 0.11 0.78 Dyslipidemia 56.1% 61.2% 61.3% 0.018 0.03 0.96 Hemodialysis 2.3% 2.1% 6.8% 0.86 &lt;0.001 0.01 Smoking 66.3% 63.1% 64.6% 0.13 0.48 0.62 Atrial fibrillation 9.6% 10.7% 14.4% 0.57 0.04 0.23 Previous MI 8.3% 17.3% 15.7% &lt;0.001 &lt;0.001 0.47 In-hospital mortality 6.0% 5.3% 1.9% 0.49 &lt;0.001 0.004

Abstract P17 Figure 1. 2.

Cyclic lava effusion during the 2018 eruption of Kīlauea Volcano

Lava flows present a recurring threat to communities on active volcanoes, and volumetric eruption rate is one of the primary factors controlling flow behavior and hazard. The time scales and driving forces of eruption rate variability, however, remain poorly understood. In 2018, a highly destructive eruption occurred on the lower flank of Kīlauea Volcano, Hawai‘i, where the primary vent exhibited substantial cyclic eruption rates on both short (minutes) and long (tens of hours) time scales. We used multiparameter data to show that the short cycles were driven by shallow outgassing, whereas longer cycles were pressure-driven surges in magma supply triggered by summit caldera collapse events 40 kilometers upslope. The results provide a clear link between eruption rate fluctuations and their driving processes in the magmatic system.

Sex-Related Differences in In-Hospital Mortality in Japanese ST-Elevation Acute Myocardial Infarction Patients Presenting to Hospital in the 24 Hours After Symptom Onset - Results From K-ACTIVE

Background: Despite the drastic advances in clinical care for patients with acute ST-elevation myocardial infarction (STEMI), female STEMI patients have higher in-hospital mortality rates than male patients. This study assessed the influence of sex on in-hospital mortality in STEMI patients in Kanagawa Prefecture, Japan.

Methods and Results: From October 2015 to June 2018, 2,491 consecutive STEMI patients (23.9% female) who presented to hospital in the 24 h after symptom onset were analyzed. The female patients were 9 years older and less frequently had diabetes, smoking and prior MI than male patients. Pre-hospital managements, including prehospital 12-lead electrocardiography, and symptom-to-door time were similar between the sexes. A door-to-device time ≤90 min was achieved in 61.3% of female cases and in 65.0% of male cases (P=0.13). Reperfusion therapy was provided to 94.6% of female and 97.6% of male patients (P<0.001). In-hospital mortality rate was not significantly different between female and male patients (6.6% vs. 7.8%, P=0.37). On multivariate logistic regression analysis, female sex itself was not associated with in-hospital mortality (OR, 1.52; 95% CI: 0.67–3.47, P=0.32).

Conclusions: There was no sex discrepancy in the in-hospital mortality of STEMI patients in this study. Guideline-based treatment, such as advanced pre-hospital management and a high use of reperfusion therapy might have attenuated the sex-related differences in the in-hospital mortality.

Multislice computed tomography assessment of everolimus-eluting Absorb bioresorbable scaffolds in comparison with metallic drug-eluting stents from the ABSORB Japan randomised trial

AIMS

Blooming artefacts limit accurate coronary assessment by multislice computed tomography (MSCT) in metallic stents. We sought to investigate whether bioresorbable vascular scaffolds (BVS) could be better assessed by MSCT.

METHODS AND RESULTS

Among 400 patients in the randomised ABSORB Japan trial, a pre-specified MSCT substudy was performed in 98 patients (103 lesions) in the BVS arm and 49 patients (49 lesions) in the cobalt-chromium everolimus-eluting stent (CoCr-EES) arm at 13 months prior to follow-up angiography. The assessability of BVS by MSCT was superior to that of CoCr-EES (94% versus 67%, p<0.001). Blooming artefacts were the main reason CoCr-EES could not be analysed (29%), while marker artefacts precluded analysis in 1.1% of BVS. In the CoCr-EES arm, non-assessable lesions were more prevalent in segments with 2.5 mm stents compared to 3.0 or 3.5 mm stents (75.0% versus 23.5%, p=0.01), while in the BVS arm image quality was good regardless of the diameter. The in-device minimal lumen diameter by MSCT was smaller than that by QCA with a difference of 0.61 mm in the CoCr-EES arm, vs. only 0.026 mm in the BVS arm.

CONCLUSIONS

The feasibility of MSCT assessment of BVS-treated lesions was greater than that for lesions with CoCr-EES.

Radial Versus Femoral Approach for Percutaneous Coronary Intervention: MACE Outcomes at Long-Term Follow-up

OBJECTIVE

To compare the main outcomes of radial versus femoral access at long-term follow-up.

BACKGROUND

Little is known about the long-term major cardiovascular events and bleeding complications of patients undergoing percutaneous coronary intervention (PCI) with radial vs femoral approach.

METHODS

A total of 1107 patients from the CENTURY II trial were included. To minimize baseline differences between radial and femoral groups, we applied propensity-score matching for this comparison.

RESULTS

In this multicenter study, the radial approach was used in 73.4% of patients. After propensity-score matching, baseline and procedural characteristics were comparable between both groups. Procedural success was high and similar in radial and femoral approaches (98.2% vs 97.5%; P=.47) while radial access was associated with a shorter hospital stay (1.69 ± 1.92 days vs 2.08 ± 1.98 days; P<.01). The short-term bleeding and vascular complication rates were significantly lower in the radial group (1.7% vs 6.2% [P<.001 in-hospital] and 2.7% vs 9.6% [P<.001 at 1-month follow-up]). At 3-year follow-up, radial access was associated with lower rates of all-cause mortality (3.9 vs 6.9%; P=.04) and cardiovascular death (2.1 vs 4.9%; P=.02). The composite of all-cause mortality, myocardial infarction, and revascularization showed no differences between groups (18.2 vs 21.1%; P=.29).

CONCLUSIONS

Compared to the femoral approach, the radial approach is associated with significantly lower long-term all-cause mortality rate as well as lower in-hospital and short-term bleeding rates. These results suggest additional long-term benefits of radial access for PCI, but should be interpreted within the context of the current study and further verified in future studies.

Risk of major bleeding at different PT-INR ranges in elderly Japanese patients with non-valvular atrial fibrillation receiving warfarin: a nested case-control study

BACKGROUND

Debate continues about the optimal anticoagulation level for elderly Japanese patients with non-valvular atrial fibrillation (NVAF) receiving warfarin. The Japanese Circulation Society guideline has recommended prothrombin time-international normalized ratios (PT-INR) of 1.6 - 2.6 for elderly patients and 2.0 - 3.0 for non-elderly patients, because previous observational studies indicated increased risk of bleeding when the ratio exceeded 2.6. We aimed to reappraise the relationship between PT-INR and the risk of major bleeding in elderly Japanese patients.

METHODS

From the electronic medical records, we selected a cohort of elderly (age ≥ 70 years) Japanese patients with NVAF who were prescribed warfarin for the prevention of thromboembolic diseases between November 2010 and March 2014 at Kanto Rosai Hospital. We identified those who developed major bleeding (cases). For each case, we randomly selected two matched controls by adopting a risk-set sampling method defined by calendar date, age, gender, length of warfarin administration, and the prescriber of warfarin. The risk of major bleeding in patients having PT-INR ≤ 1.49, 1.50 - 1.99, 2.00 - 2.49 (the reference), 2.50 - 2.99, and ≥ 3.00 were compared using the conditional logistic regression method. The study protocol was approved by the IRB before the study was begun.

RESULTS

Among the cohort of 806 elderly patients, we identified 32 cases and selected 64 matched controls. The overall incidence of major bleeding was 3.5 per 100 patient-years. The odds ratios (95 % confidence intervals) for the risk of developing major bleeding in patients with PT-INR ≤ 1.49 (n = 20), 1.50 - 1.99 (n = 32), 2.00 - 2.49 (n = 18), 2.50 - 2.99 (n = 10), and ≥ 3.00 (n = 16) were 1.0 (0.2, 5.9), 0.3 (0.1, 1.9), 1.0 (reference), 1.2 (0.2, 8.4), and 19.8 (2.0, 198.9), respectively, with a significant difference between ≥ 3.00 and reference.

CONCLUSIONS

Among elderly Japanese patients with NVAF, PT-INR 2.0 - 3.0 may be associated with a clinically permissible risk of major bleeding while PT-INR ≥ 3.00 a significant risk. Further studies are warranted to determine whether the risk of major bleeding is significantly lower for PT-INR 2.50 - 2.99 than for PT-INR ≥ 3.00.

Prediction of progression of coronary artery disease and clinical outcomes using vascular profiling of endothelial shear stress and arterial plaque characteristics: the PREDICTION Study

BACKGROUND

Atherosclerotic plaques progress in a highly individual manner. The purposes of the Prediction of Progression of Coronary Artery Disease and Clinical Outcome Using Vascular Profiling of Shear Stress and Wall Morphology (PREDICTION) Study were to determine the role of local hemodynamic and vascular characteristics in coronary plaque progression and to relate plaque changes to clinical events.

METHODS AND RESULTS

Vascular profiling, using coronary angiography and intravascular ultrasound, was used to reconstruct each artery and calculate endothelial shear stress and plaque/remodeling characteristics in vivo. Three-vessel vascular profiling (2.7 arteries per patient) was performed at baseline in 506 patients with an acute coronary syndrome treated with a percutaneous coronary intervention and in a subset of 374 (74%) consecutive patients 6 to 10 months later to assess plaque natural history. Each reconstructed artery was divided into sequential 3-mm segments for serial analysis. One-year clinical follow-up was completed in 99.2%. Symptomatic clinical events were infrequent: only 1 (0.2%) cardiac death; 4 (0.8%) patients with new acute coronary syndrome in nonstented segments; and 15 (3.0%) patients hospitalized for stable angina. Increase in plaque area (primary end point) was predicted by baseline large plaque burden; decrease in lumen area (secondary end point) was independently predicted by baseline large plaque burden and low endothelial shear stress. Large plaque size and low endothelial shear stress independently predicted the exploratory end points of increased plaque burden and worsening of clinically relevant luminal obstructions treated with a percutaneous coronary intervention at follow-up. The combination of independent baseline predictors had a 41% positive and 92% negative predictive value to predict progression of an obstruction treated with a percutaneous coronary intervention.

CONCLUSIONS

Large plaque burden and low local endothelial shear stress provide independent and additive prediction to identify plaques that develop progressive enlargement and lumen narrowing.

CLINICAL TRIAL REGISTRATION

URL: http:www.//clinicaltrials.gov. Unique Identifier: NCT01316159.

Prediction of progression of coronary artery disease and clinical outcomes using vascular profiling of endothelial shear stress and arterial plaque characteristics: the PREDICTION Study

BACKGROUND

Atherosclerotic plaques progress in a highly individual manner. The purposes of the Prediction of Progression of Coronary Artery Disease and Clinical Outcome Using Vascular Profiling of Shear Stress and Wall Morphology (PREDICTION) Study were to determine the role of local hemodynamic and vascular characteristics in coronary plaque progression and to relate plaque changes to clinical events.

METHODS AND RESULTS

Vascular profiling, using coronary angiography and intravascular ultrasound, was used to reconstruct each artery and calculate endothelial shear stress and plaque/remodeling characteristics in vivo. Three-vessel vascular profiling (2.7 arteries per patient) was performed at baseline in 506 patients with an acute coronary syndrome treated with a percutaneous coronary intervention and in a subset of 374 (74%) consecutive patients 6 to 10 months later to assess plaque natural history. Each reconstructed artery was divided into sequential 3-mm segments for serial analysis. One-year clinical follow-up was completed in 99.2%. Symptomatic clinical events were infrequent: only 1 (0.2%) cardiac death; 4 (0.8%) patients with new acute coronary syndrome in nonstented segments; and 15 (3.0%) patients hospitalized for stable angina. Increase in plaque area (primary end point) was predicted by baseline large plaque burden; decrease in lumen area (secondary end point) was independently predicted by baseline large plaque burden and low endothelial shear stress. Large plaque size and low endothelial shear stress independently predicted the exploratory end points of increased plaque burden and worsening of clinically relevant luminal obstructions treated with a percutaneous coronary intervention at follow-up. The combination of independent baseline predictors had a 41% positive and 92% negative predictive value to predict progression of an obstruction treated with a percutaneous coronary intervention.

CONCLUSIONS

Large plaque burden and low local endothelial shear stress provide independent and additive prediction to identify plaques that develop progressive enlargement and lumen narrowing.

CLINICAL TRIAL REGISTRATION

URL: http:www.//clinicaltrials.gov. Unique Identifier: NCT01316159.

Randomized comparison of the Nobori biolimus A9-eluting stent with the sirolimus-eluting stent in patients with stenosis in native coronary arteries

OBJECTIVES

The aim of this randomized-controlled trial is to compare biolimus A9-eluting stent (Nobori) to sirolimus eluting stent (Cypher).

BACKGROUND

The Nobori coronary stent is coated only abluminally with a biodegradable polymer, poly-lactic acid, and the antiproliferative agent biolimus A9. This stent has been studied in randomized trials versus Taxus Express and Taxus Liberte and showed noninferiority and superiority for in-stent late loss. This is the first randomized trial of Nobori stent versus Cypher stent.

METHODS

We conducted a randomized (3:2), controlled trial comparing Nobori and Cypher, in 335 patients (198 Nobori and 137 Cypher) at 15 centers in Japan. Patients with de-novo lesions in up to two native coronary arteries were considered for enrollment. The primary endpoint was freedom from target vessel failure (TVF), a composite of cardiac death, myocardial infarction, and target vessel revascularization at 9 months.

RESULTS

At 9 months, the primary endpoint of freedom from TVF was 92.6% in Nobori and 93.8% in Cypher arm (noninferiority test P < 0.001). As main secondary endpoints, the in-stent late loss was 0.12 ± 0.30 mm and 0.14 ± 0.34 mm in Nobori and Cypher stents, respectively. Target lesion revascularization was 0.5% in Nobori and 3.9% in Cypher treated patients (P = 0.04). Definite and probable stent thromboses were not recorded in any patient.

CONCLUSIONS

Despite the relatively small number of patients, this well controlled clinical trial confirmed the primary hypothesis of non-inferiority of the Nobori biolimus A9-eluting stent to the Cypher sirolimus-eluting stent for freedom from TVF. Both stents showed excellent midterm results.

Adenosine and adenosine uptake inhibitors potentiate the neuromuscular blocking action of rocuronium mediated by adenosine A(1) receptors in isolated rat diaphragms

BACKGROUND

Adenosine, which pre-junctionally modulates neuromuscular transmission, and adenosine uptake inhibitors, which increase extracellular adenosine, have been used clinically. We investigated the effects of adenosine, dipyridamole and midazolam on the neuromuscular blocking action of rocuronium.

METHODS

Isometric twitch tensions of rat nerve-hemidiaphragm preparations elicited by indirect (phrenic nerve) supra-maximal stimulation at 0.1 Hz were evaluated (n=6 in all data).

RESULTS

Pre-treatments with adenosine (0.1 and 1 microM) and CCPA (1 microM, adenosine A(1) receptor agonist), but not that with CGS21680 (0.5 microM, A(2) receptor agonist), shifted the rocuronium concentration-twitch tension curves to the left and decreased the rocuronium concentration for 50% twitch depression (IC(50)) compared with the control (P<0.01). The leftward shift induced by 1 microM adenosine was inhibited by pre-treatments with theophylline (50 microM, non-selective adenosine receptor antagonist) and DPCPX (0.2 microM, A(1) receptor antagonist) but not by that with DPMA (5 microM, A(2) receptor antagonist). Pre-treatments with dipyridamole and midazolam, adenosine uptake inhibitors, shifted the curve to the left and decreased IC(50) at supra-therapeutic concentrations (10 and 2.5 microM, respectively) but not at clinical concentrations (2 and 0.5 microM, respectively), and the leftward shifts were inhibited by pre-treatment with DPCPX (0.2 microM).

CONCLUSION

The results indicate that adenosine potentiates the neuromuscular blocking action of rocuronium mediated by adenosine A(1) receptors and that supra-therapeutic concentrations of dipyridamole and midazolam also potentiate the action of rocuronium by increasing endogenous adenosine concentration.

Propofol attenuates ischaemia-reperfusion injury in the rat heart in vivo

BACKGROUND

We have previously demonstrated, in the isolated rat heart, that propofol attenuates hydrogen peroxide-induced damage and ischaemia-reperfusion injury, and that the beneficial effect of propofol is correlated with reduction of the lipid peroxidation. This study was designed to evaluate whether propofol has a cardioprotective effect against ischaemia-reperfusion injury in a rat model in vivo.

METHODS

Adult rats were anaesthetized with pentobarbital 10 mg kg(-1) h(-1) alone (control group), pentobarbital 10 or 20 mg kg(-1) h(-1) + Intralipid as a vehicle (Pent-10, Pent-20 group), propofol 10 or 20 mg kg(-1) h(-1) (Prop-10, Prop-20 group) intravenously throughout the experiment. The left anterior descending coronary artery was occluded for 30 min followed by 120 min of reperfusion. Infarct size was determined at the end of reperfusion. The tissue concentration of malondialdehyde was measured at 30 min after reperfusion to evaluate lipid peroxidation.

RESULTS

The infarct sizes (% of area at risk) were significantly smaller in the Prop-10 (54 +/- 11%; P < 0.01 vs. control) and Prop-20 (39 +/- 8%; P < 0.01 vs. control) groups than in the control (68 +/- 9%), Pent-10 (69 +/- 13%) and Pent-20 (68 +/- 14%) groups (n = 12). In the Pent-10 and Pent-20 groups, ischaemia-reperfusion produced significant increases in the values for tissue malondialdehyde (0.72 +/- 0.24 micromol mg protein-1; P < 0.05 and 0.63 +/- 0.33 micromol mg protein-1; P < 0.05 vs. 0.46 +/- 0.22 micromol mg protein-1 in non-ischaemic hearts, n = 8). However, the values of malondialdehyde in the Prop-10 and -20 groups were suppressed by 41% and 63%, respectively, compared with the Pent-10 group (P < 0.01).

CONCLUSION

Our results suggest that propofol could be cardioprotective against ischaemia-reperfusion injury dose dependently in a rat model in vivo and that the beneficial action of propofol may be correlated with its antioxidant effect.

Inhibitory effects of the alpha-2 adrenergic agonists clonidine and dexmedetomidine on enhanced airway tone in ovalbumin-sensitized guinea pigs

BACKGROUND AND OBJECTIVE

The alpha-2 adrenergic agonists clonidine and dexmedetomidine are used as an antihypertensive and a sedative, respectively. The aim of this study was to determine the effects of these agonists on ovalbumin-sensitized airway tone in guinea pigs.

METHODS

The animals were divided into two groups: control and sensitized. The sensitized group received ovalbumin intraperitoneally and was boosted by exposure to aerosolized ovalbumin. The effects of the alpha-2 agonists were investigated by measuring (1) total lung resistance and (2) smooth muscle tension using a tracheal ring preparation.

RESULTS

In the control group, acetylcholine significantly increased total lung resistance in a dose-dependent manner. In the sensitized animals, total lung resistance was significantly higher (by 95%) at 6 mug kg-1 acetylcholine than that in the control group. Both clonidine and dexmedetomidine had a slight but significant inhibitory effect on the response curve of lung resistance at higher concentrations of carbachol, a potent muscarinic receptor agonist. Similar to the data obtained in the control group, both clonidine and dexmedetomidine significantly decreased total lung resistance and the inhibitory effects of these alpha-2 agonists on lung resistance were significantly distinguishable. Similar direct inhibitory effects of the alpha-2 agonists on carbachol-induced muscle contraction were observed in both the control and sensitized groups, the inhibitory effects in the sensitized group being significantly greater.

CONCLUSION

Both clonidine and dexmedetomidine can relax the airway even in the hyper-reactive state.

Analysis of the composition of 'original' and generic sevoflurane in routine use

BACKGROUND

Original sevoflurane (Sevofrane) contains a small amount of water, which can inhibit the production of hydrofluoric acid. Hydrofluoric acid is highly pungent, and sevoflurane that contains a high concentration of hydrofluoric acid is not suitable for volatile induction of anaesthesia. Recently, generic sevoflurane (Sevoness) has become available in some countries. The generic product is produced by a different method and kept in a different kind of bottle. We questioned whether the original and generic sevoflurane differed in their composition and thus might differ in their resistance to degradation.

METHODS

Sevoflurane from groups of three bottles of Sevofrane and three bottles of Sevoness was kept in the bottle at 24-37 degrees C for 2 weeks or in two kinds of vaporizer for 3 days, and the resulting contents measured by gas chromatography.

RESULTS

Both products contained sevoflurane concentrations exceeding 99.998%. Fluoride ion concentration did not differ between the products (0.043 ppm). The original sevoflurane contained more (0.07% w/v) water than the generic anaesthetic (0.003% w/v). Original sevoflurane contained 5 ppm compound A, 10 ppm sevomethylether, and 5 ppm of unknown materials. Generic sevoflurane contained 32 ppm hexafluoroisopropanol and 12 ppm of unknown materials. While stored in a vaporizer for 3 days, the water content in the original sevoflurane decreased by two-thirds but the water in the generic sevoflurane increased by a factor of three-fold.

CONCLUSIONS

Generic sevoflurane contains high-quality sevoflurane and only a small amount of fluoride ions, making it comparable with the original sevoflurane product.

Bone cancer increases transient receptor potential vanilloid subfamily 1 expression within distinct subpopulations of dorsal root ganglion neurons

Bone cancer pain has a strong impact on the quality of life of patients but is difficult to treat. Therefore, the mechanisms of bone cancer pain require elucidation for the purpose of development of new therapeutics. A recent study showed that activation of transient receptor potential vanilloid subfamily 1 (TRPV1) was involved in bone cancer pain. In this study, we re-evaluated the analgesic effects of pharmacological blockade of TRPV1 using the potent TRPV1 antagonist 5-iodoresiniferatoxin (I-RTX) and examined whether bone cancer can change TRPV1 expression and distribution in the primary sensory neurons in a mouse model of bone cancer pain. Implantation of osteosarcoma into the femur induced ongoing and movement-evoked bone cancer-related pain behaviors. These behaviors were significantly reduced by i.p. administration of I-RTX, compared with vehicle. Western blot and reverse transcription-polymerase chain reaction (RT-PCR) analyses revealed that TRPV1 level was significantly increased in dorsal root ganglions (DRGs) ipsilateral to sarcoma implantation. Immunohistochemical analysis showed that implantation of osteosarcoma induced not only an increase in the percentage of TRPV1-positive neurons among DRG neurons (24.3+/-1.3% in sham mice and 31.2+/-1.3% in mice with osteosarcoma implantation, P<0.05) but also an overall shift in the distribution of area of profiles to the right. Colocalization study showed that the percentages of colocalization of TRPV1 with neurofilament 200 kD (NF200) and calcitonin gene-related peptide (CGRP) but not isolectin B4 (IB4) among DRG neurons in mice with osteosarcoma implantation were increased compared with those in sham mice (from 0.8+/-0.1% to 2.1+/-0.3% for TRPV1 and NF200 and from 21.1+/-1.3% to 26.5+/-0.2% for TRPV1 and CGRP). In conclusion, TRPV1 activation plays a critical role in the generation of bone cancer pain, and bone cancer increases TRPV1 expression within distinct subpopulation of DRG neurons. These findings may lead to novel strategies for the treatment of bone cancer pain.

Immunohistochemical analysis of acid-sensing ion channel 2 expression in rat dorsal root ganglion and effects of axotomy

Several studies have suggested that acid-sensing ion channel 2 (ASIC2) plays a role in mechanoperception and acid sensing in the peripheral nervous system. We examined the expression and distribution of ASIC2 in the rat dorsal root ganglion, the co-localization of ASIC2 with tropomyosin-related kinase (trk) receptors, and the effects of axotomy on ASIC2 expression. ASIC2 immunoreactivity was observed in both neurons and satellite cells. ASIC2-positive neurons accounted for 16.5 +/- 2.4% of the total neurons in normal dorsal root ganglion. Most ASIC2-positive neurons were medium-to-large neurons and were labeled with neurofilament 200 kD (NF200). Within these neurons, ASIC2 was not evenly distributed throughout the cytoplasm, but rather was accumulated prominently in the cytoplasm adjacent to the axon hillock and axonal process. We next examined the co-localization of ASIC2 with trk receptors. trkA was expressed in few ASIC2-positive neurons, and trkB and trkC were observed in 85.2% and 53.4% of ASIC2-positive neurons, respectively, while only 6.9% of ASIC2-positive neurons were co-localized with trkC alone. Peripheral axotomy markedly reduced ASIC2 expression in the axotomized dorsal root ganglion neurons. On the other hand, intense ASIC2 staining was observed in satellite cells. These results show that ASIC2 is expressed in the distinct neurochemical population of sensory neurons as well as satellite cells, and that peripheral axotomy induced marked reductions in ASIC2 in neurons.

Effects of thiopental on bispectral index and heart rate variability

BACKGROUND AND OBJECTIVE

Thiopental has been reported to reduce sympathetic tone, however, it is not clear whether change in heart rate variability is associated with depth of anaesthesia. The purpose of the present study was to evaluate changes in heart rate variability at different depths of hypnosis during induction of anaesthesia with thiopental.

METHODS

We studied 17 ASA I patients scheduled for minor surgery. The depth of hypnosis was monitored by the BIS. Spectral analysis of heart rate variability using a maximum entropy method resulted in a characteristic power spectrum with two main regions, a high frequency and a low frequency. Haemodynamics, entropy, low frequency, high frequency and low frequency/high frequency were monitored in an awake state and after the induction of anaesthesia.

RESULTS

Heart rate increased in a BIS-dependent manner, whereas blood pressure showed no significant changes during the study period. High frequency, entropy and low frequency decreased with a reduction in the BIS value. Low frequency/high frequency showed no significant change during the study period.

CONCLUSIONS

Induction of anaesthesia with thiopental increased heart rate and decreased high frequency, entropy and low frequency in a BIS-dependent manner, indicating that thiopental reduces cardiac parasympathetic tone depending on the depth of hypnosis.

Performance of three systems for warming intravenous fluids at different flow rates

This study compared the intravenous fluid warming capabilities of three systems at different flow rates. The devices studied were a water-bath warmer, a dry-heat plate warmer, and an intravenous fluid tube warmer Ambient temperature was controlled at 22 degrees to 24 degrees C. Normal saline (0.9% NaCl) at either room temperature (21 degrees to 23 degrees C) or at ice-cold temperature (3 degrees to 5 degrees C) was administered through each device at a range of flow rates (2 to 100 ml/min). To mimic clinical conditions, the temperature of the fluid was measured with thermocouples at the end of a one metre tube connected to the outflow of the warmer for the first two devices and at the end of the 1.2 m warming tubing for the intravenous fluid tube warmer The temperature of fluid delivered by the water bath warmer increased as the flow rate was increased up to 15 to 20 ml/min but decreased with greater flow rates. The temperature of the fluid delivered by the dry-heat plate warmer significantly increased as the flow rate was increased within the range tested (due to decreased cooling after leaving the device at higher flow rates). The temperature of fluid delivered by the intravenous fluid tube warmer did not depend on the flow rate up to 20 ml/min but significantly and fluid temperature-dependently decreased at higher flow rates (>30 ml/min). Under the conditions of our testing, the dry heat plate warmer delivered the highest temperature fluid at high flow rates.

Angular distributions of H-induced HD and D2 desorptions from the Si(100) surfaces

We measured angular distributions of HD and D2 molecules desorbed via the reactions H+DSi(100)-->HD [abstraction (ABS)] and H+DSi(100)-->D2 [adsorption-induced-desorption (AID)], respectively. It was found that the angular distribution of HD molecules desorbed along ABS is broader than that of D2 molecules desorbed along AID, i.e., the former could be fit with cos(2.0+/-0.2) theta, while the latter with cos(5.0+/-0.5) theta. This difference of the angular distributions between the two reaction paths suggests that their dynamic mechanisms are different. The observed cos2 theta distribution for the ABS reaction was reproduced by the classical trajectory calculations over the London-Eyring-Polanyi-Sato potential-energy surfaces. The simulation suggests that the HD desorption along the ABS path takes place along the direction of Si-D bonds, but the apparent angular distribution is comprised of multiple components reflecting the different orientations of D-occupied Si dimers in the (2 x 1) and (1 x 2) double domain structures.

Use of percutaneous cardiopulmonary support in catastrophic massive pulmonary fat embolism

We report a patient who sustained massive catastrophic pulmonary fat embolism while undergoing surgery for intramedullary nail of femur. Application of percutaneous cardiopulmonary support, in our view, saved the patient from cardiopulmonary collapse.

Desorption dynamics of deuterium molecules from the Si(100)-(3x1) dideuteride surface

We measured polar angle (theta)-resolved time-of-flight spectra of D2 molecules desorbing from the Si(100)-(3x1) dideuteride surface. The desorbing D2 molecules exhibit a considerable translational heating with mean desorption kinetic energies of approximately 0.25 eV, which is mostly independent of the desorption angles for 0 degrees<or=theta<or=30 degrees. The observed desorption dynamics of deuterium was discussed along the principle of detailed balance to predict their adsorption dynamics onto the monohydride Si surface.

Endothelin-1 enhances capsaicin-evoked intracellular Ca2+ response via activation of endothelin a receptor in a protein kinase Cε-dependent manner in dorsal root ganglion neurons

Increasing evidence indicates that endothelin-1 has a role for peripheral nociceptive signaling in animals and humans. However, the mechanisms of the nociceptive effects of endothelin-1 have not been fully understood. The current study investigated the effects of endothelin-1 on the capsaicin-evoked intracellular Ca2+ response of cultured adult mice dorsal root ganglion neurons. Dorsal root ganglia were harvested from adult male C57B6N mice and were cultured. With a digital image analysis system, we detected the [Ca2+]i image of cultured dorsal root ganglion cells after loading with Fura-2 acetoxymethyl. In addition, co-localization of protein kinase Cepsilon with transient receptor potential V1 and the translocation of protein kinase Cepsilon were investigated using immunohistochemical methods. Endothelin-1 (10 nM) enhanced an increase in [Ca2+]i by capsaicin (10 nM) from 87.6+/-11.6 nM to 414.8+/-62.3 nM (71 of 156 neurons). The inhibition of endothelin A receptor (BQ-123) significantly suppressed the enhancing effect of endothelin-1. In addition, a nonselective protein kinase C inhibitor (bisindolylmaleimide I) significantly suppressed the enhancing effect of endothelin-1. A myristoyl-tagged membrane-permeant-protein kinase Cepsilon V1-2 inhibitory peptide also significantly suppressed the enhancing effect of endothelin-1. In the immunocytochemical study, protein kinase Cepsilon immunoreactivity was found in most of transient receptor potential V1-positive neurons. After endothelin-1 application, protein kinase Cepsilon immunoreactivity was observed to be translocated from the cytosol to the cell membrane in transient receptor potential V1-positive neurons. Our results indicate that endothelin-1 enhances the response of dorsal root ganglion neurons to capsaicin in a protein kinase Cepsilon-dependent manner. Our findings may lead to a new strategy to treat pain associated with endothelin-1.

Comparative study between propofol in a long-chain triglyceride and propofol in a medium/long-chain triglyceride during sedation with target-controlled infusion

This study was performed to compare the pharmacological characteristics of propofol in an emulsion of both medium- and long-chain triglycerides (MCT/LCT) with those of propofol in an LCT emulsion, by measuring the sedative level and the plasma concentration of propofol during sedation using a target-controlled infusion (TCI) technique. Forty ASA 1 or 2 adult patients who required spinal anaesthesia for surgery were enrolled in this study. The patients were divided into two groups: a propofol LCT group (n = 20) and a propofol MCT/LCT group (n = 20). Propofol was injected intravenously at target blood concentrations of 2.0, 3.0 and 4.0 microg x ml(-1). The bispectral (BIS) index was recorded, and arterial blood was drawn to measure the actual plasma concentrations of propofol at each predicted concentration. Propofol was assayed by high-performance liquid chromatography. Propofol MCT/LCT was associated with significantly less pain than propofol LCT (P < 0.05). There were no significant differences between the two groups in BIS index or in plasma concentration of propofol at each predicted concentration. Computer-generated TCI of propofol MCT/LCT during sedation is comparable with that of propofol LCT with respect to pharmacokinetics and pharmacodynamics. The formulation of MCT/LCT has a beneficial effect with respect to less pain on injection.