Utility of Automated Infrared Pupillometry in Assessing the Prolonged Course of Organophosphate Poisoning: A Case Report.

Central and autonomic nervous system signs of organophosphate poisoning (OP), such as altered consciousness, noticeable lacrimation, and salivation, can be influenced by medications used in intensive care settings, such as atropine and pralidoxime methyl (PAM). Because of this, there are no established methods for assessing the duration of OP while receiving antidotal treatment. In the present case, we used the Neurological Pupil Index (NPi) to evaluate the duration of OP in an 82-year-old woman who attempted suicide by ingesting up to 100 mL of fenitrothion. Until hospitalization day (HD) 20, discontinuation of atropine led to the recurrence of altered consciousness, while its reinstatement resulted in improvement; this made it difficult to assess the prolongation of OP based on signs and symptoms. Until HD 20, the NPi remained at 0/0, and subsequently, it increased. Additionally, even after discontinuing atropine, consciousness, tearing, and salivation did not worsen, indicating recovery from OP. On HD 26, serum acetylcholinesterase (AChE) levels were elevated above the measurable level for the first time, following an increase in the NPi. In this case, assessing the persistence of OP based on signs was challenging because these signs improved with atropine and PAM treatment. The improvement in NPi levels coincided with an improvement in poisoning, suggesting that NPi is useful for evaluating the duration of OP. NPi is noninvasive and sensitive compared to AChE, which is used to gauge the persistence of OP and could be used to allow earlier cessation of medication and guide appropriate treatment durations.

Evaluating the relationship between ocular blood flow and systemic organ blood flow in hemorrhagic shock using a rabbit model.

This study aimed to investigate the feasibility of utilizing noninvasive ocular blood flow measurements as potential indicators of systemic circulation in rabbits experiencing hemorrhagic shock. Using Laser speckle flowgraphy, ocular blood flow indices, relative flow volume (RFV), and mean blur rate in the choroidal area (MBR-CH) were assessed in New Zealand White rabbits (n = 10) subjected to controlled blood removal and return. Hemodynamic parameters and biochemical markers were monitored alongside ocular circulation during blood removal and return phases. Additionally, correlations between ocular parameters and systemic indices were examined. The results indicated that RFV and MBR-CH exhibited significant correlations with renal and intestinal blood flows, with stronger correlations observed during blood removal. Additionally, ocular blood flow changes closely mirrored systemic dynamics, suggesting their potential as real-time indicators of shock progression and recovery. These findings indicate that ocular blood flow measurements may serve as real-time indicators of the systemic circulation status during hemorrhagic shock, offering potential insights into shock management and guiding tailored interventions. Thus, noninvasive ocular blood flow evaluation holds promise as an innovative tool for assessing systemic circulation dynamics during hemorrhagic shock.

CT-Guided Intranodal Lymphangiography for Postoperative Chylous Ascites.

The utility and minimal invasiveness of ultrasound-guided intranodal lymphangiography have already been reported by several researchers. Although ultrasound-guided intranodal lymphangiography is known to be not technically difficult in general, a patient's edematous groin due to hypoalbuminemia resulting from chylous ascites made it too challenging to detect and prick the lymph nodes precisely. This report describes a 71-year-old female with refractory chylous ascites due to an operation for an extrahepatic bile duct cancer, who was successfully treated by computed tomography (CT)-guided intranodal lymphangiography. After switching from ultrasound- to CT-guided lymphangiography, the procedure was successfully performed, and the refractory chylous ascites was treated.

Predictive importance of left ventricular myocardial stiffness for the prognosis of patients with congestive heart failure.

OBJECTIVES: This study was designed to determine the prognostic importance of left ventricular (LV) myocardial stiffness, a hemodynamic index which is closely related to B-type natriuretic peptide (BNP) concentration in patients with congestive heart failure (CHF). BACKGROUND: While elevated BNP, an abnormality of cardiac neurohormones, is known to be an independent marker of death or re-admission, it remains to be clarified whether there is also a strong predictor directly related to cardiac dysfunction. METHODS: LV performance variables and stress-strain analyses including diastolic myocardial stiffness constant (K(m)) were obtained from 37 patients with initial CHF by the combined simultaneous measurement of echocardiographic and hemodynamic data. Survivors were monitored for a mean of 23 months, with the main endpoint being combined death or first re-admission for CHF. RESULTS: Ten patients (27%) were primary endpoint cases. Both K(m) and plasma BNP levels were higher in the event than in the event-free group. By Cox proportional hazards analysis, K(m)≥4.0 was identified as the only variable with significant and independently incremental predictive power to affect the primary endpoint (adjusted hazard ratio=7.354, 95% confidence interval 1.379-39.232, p=0.02). CONCLUSIONS: In patients with CHF, increased myocardial stiffness may have greater prognostic significance compared to other conventional predictors. Increased myocardial stiffness may be considered to be an important prognostic factor independent of the loading conditions.

Comparison by optical coherence tomography of paclitaxel-eluting stents with sirolimus-eluting stents implanted in one coronary artery in one procedure. - 6-month follow-up -.

BACKGROUND: Differences between paclitaxel-eluting stents (PES) and sirolimus-eluting stent (SES) in neointimal proliferation under strictly matched conditions remain to be clarified by optical coherence tomography (OCT). METHODS AND RESULTS: Between May and December 2007, 27 patients were implanted with a PES and a SES, randomized to either the proximal or distal site in a single coronary artery, and underwent follow-up angiography and OCT examination at 6 months. The frequency of vessel wall apposition with neointima was greater for PES than for SES (92.6% vs 85.8%, P<0.01). The median (25th, 75th percentiles) neointimal thickness (NIT) in PES was significantly greater than that in SES (90 microm [25th: 40 microm; 75th: 200 microm] vs 50 microm [25th: 20 microm; 75th: 140 microm]; P<0.01). Both the average difference between the maximum and minimum NIT in each cross-section and the average difference between the maximum and minimum NIT in the longitudinal axis were larger in PES than in SES (206+/-88 vs 131+/-57 microm; P<0.001, 607+/-243 vs 400+/-185 microm; P<0.001). Low-density spots were significantly more frequently observed in PES than in SES (30.9% vs 17.0%, P=0.001). CONCLUSIONS: Compared with SES, PES had a non-uniform and larger neointimal thickness with fewer uncovered struts, and more peri-strut low-density areas.

Low plasma adiponectin levels are associated with presence of thin-cap fibroatheroma in men with stable coronary artery disease.

BACKGROUND: Previous studies demonstrated the inverse association of adiponectin with coronary artery disease (CAD) especially in men with acute coronary syndrome, however their association with in vivo plaque vulnerability in stable CAD, which may be reflected by the thin-cap fibroatheroma (TCFA) prevalence, remains unknown. METHODS: In 50 men with stable CAD, we identified TCFA with multi-vessel examination of combined use of virtual histology intravascular ultrasound (VH-IVUS) and optical coherence tomography (OCT). The definition of TCFA was described as follows; necrotic-core rich lesion (% necrotic-core >10%) without evidence of an overlying fibrous component and % plaque-volume >40% in at least 3 consecutive frames by VH-IVUS, and the thinnest fibrous-cap thickness <65 microm by OCT. The patients were divided into two groups, patients with TCFA and without TCFA, and plasma adiponectin level was compared between the groups. RESULTS: Among 50 patients, we could observe 116 vessels (2.32+/-0.47 vessel/patient). At least one TCFA was identified in 20 patients. Patients with TCFA had significantly lower plasma adiponectin levels than patients without TCFA (P<0.0001). Furthermore, the plasma adiponectin levels in patients with multi-vessel TCFA were significantly lower than those in patients with single-vessel TCFA (P=0.049). Multivariate logistic regression analysis revealed that plasma adiponectin was the strongest predictive factor of the presence of TCFA (P=0.0007). CONCLUSIONS: Low plasma adiponectin was associated with the presence of TCFA in men with stable CAD. This finding suggests that, in these subjects, it may be a biomarker that can be used to stratify "vulnerable patients" into risk categories.

Factors that influence measurements and accurate evaluation of stent apposition by optical coherence tomography. Assessment using a phantom model.

BACKGROUND: Factors influencing measurements and accurate evaluation of stent apposition by optical coherence tomography (OCT) are not established. METHODS AND RESULTS: Phantom models of known luminal sizes and lengths were evaluated by OCT under various conditions and measurements were compared with actual values. Stents implanted into phantom models were examined by OCT to validate the measurement point on the stent strut surface for accurate evaluation of stent apposition. Strut thickness was measured at 3 points (midpoint, inner and outer surfaces of the stent shadow). The precision of OCT measurements of lumen diameter and area was satisfactory when the image wire was positioned in the center, but the error and deviation were unsatisfactory when the image wire was positioned eccentrically using a low frame acquisition rate. Longitudinal OCT measurements were close to actual values under all conditions examined. Measurements from the midpoint of the stent shadow to the adjacent vessel wall surface coincided with actual stent thickness. CONCLUSIONS: Significant measurement error can occur if the image wire is positioned eccentrically with a lower frame acquisition rate than specified by the manufacturer. To accurately evaluate stent apposition, the stent surface should be measured from the center of the stent reflection.

Local determinants of thrombus formation following sirolimus-eluting stent implantation assessed by optical coherence tomography.

OBJECTIVES: We conducted this study to assess the prevalence and determinants of subclinical thrombus after sirolimus-eluting stent (SES) implantation. BACKGROUND: Angioscopic analyses have demonstrated the presence of thrombus is more common than the clinical incidence of SES thrombosis. METHODS: Fifty-three patients (53 lesions) underwent 6-month follow-up optical coherence tomography. A stent eccentricity index ([SEI] minimum/maximum stent diameter) was determined in each cross section. To evaluate unevenness of neointimal thickness, a neointimal unevenness score ([NUS] maximum neointimal thickness in the cross section/average neointimal thickness of the same cross section) was calculated for each cross section. Average SEI and NUS were calculated for each stent. Major adverse cardiac events were defined as a composite of death, myocardial infarction, and target vessel revascularization. RESULTS: Fourteen cases of thrombus (26%) were detected by optical coherence tomography (thrombus: n = 14 vs. nonthrombus: n = 39). The percentage of thrombus was associated with longer stents (36.4 +/- 20.2 mm vs. 25.1 +/- 9.8 mm; p = 0.008), a larger number of uncovered struts (17 +/- 16 vs. 8 +/- 11; p = 0.03), smaller average SEI (0.89 +/- 0.04 vs. 0.92 +/- 0.03; p = 0.001), and greater average NUS (2.22 +/- 0.24 vs. 2.00 +/- 0.33; p = 0.03). A significant relationship existed between average SEI and average NUS (p < 0.0001, R = 0.68), and between average SEI and the number of uncovered struts (p < 0.0006, R = 0.46). There was no significant difference in major adverse cardiac events during follow-up (median: 485 days, 7.1% vs. 12.8%; p > 0.99). CONCLUSIONS: Longer stents and greater asymmetric stent expansion may be important determinants of thrombus formation after SES implantation. In this small cohort, the presence of thrombus did not increase the risk of major adverse cardiac events.

Whole body bioimpedance monitoring for outpatient chronic heart failure follow up.

BACKGROUND: Although cardiac output index (CI), stroke volume index (SVI), and total systemic vascular resistance (TSVR) are important hemodynamic parameters for the prognosis of chronic heart failure (CHF), they are difficult to measure in an outpatient setting. Whole body bioimpedance monitoring using a Non-Invasive Cardiac System (NICaS) allows for easy, non-invasive estimation of these parameters. Here, whether NICaS-derived hemodynamic parameters are clinically significant was investigated by relating them to other conventional cardiovascular functional indices, and by evaluating their predictive accuracy for CHF readmission. METHODS AND RESULTS: Study subjects of 68 patients with CHF were enrolled in the study immediately upon discharge from the hospital. NICaS-derived CI, -SVI, and -TSVR values obtained at an outpatient clinic were significantly related with left ventricular ejection fraction (LVEF) measured by echocardiography, serum B-type natriuretic peptide (BNP), and exercise tolerance. During the 100 +/-98 days follow-up, 15 patients were readmitted to our hospital for CHF recurrence. Multivariate analysis indicated that LVEF, NICaS-derived CI, NICaS-derived SVI, and plasma BNP were significant indicators (receiver operating characteristic curve cut-off point, LVEF: 37%, NICaS-derived CI: 2.49L x min-1 x m(-2), NICaS-derived SVI: 27.2 ml/m(2), plasma BNP: 344 pg/ml) for readmission. CONCLUSIONS: Hemodynamic parameters derived by NICaS are applicable for the non-invasive assessment of cardiac function in outpatient CHF follow up.

Delayed neointimalization on sirolimus-eluting stents: 6-month and 12-month follow up by optical coherence tomography.

BACKGROUND: Sirolimus-eluting stents (SES) have incomplete neointimal coverage at 6-month follow up as determined with optical coherence tomography (OCT). The long-term detailed changes of neointima in SES remains to be clarified. METHODS AND RESULTS: Serial changes in neointimal coverage of SES from 6 months to 12 months using OCT were examined. Of 21 SES in 13 patients, OCT was used to visualize 2,321 stent struts at 6 months and 2,285 stent struts at 12 months. The frequency of struts without neointimal coverage decreased from 6 months to 12 months (from 10.4 to 5.7%). The frequency of malapposed struts decreased from 6 months to 12 months (from 1.7 to 0.2%). The average thickness of the neointima increased (from 112 +/-123 to 120 +/-130 microm). The frequency of struts located at the side branch orifice without neointima decreased (from 4 out of 17 (24%) to 0 out of 17 (0%)). Complete coverage with neointima was observed in 14% (3 of 21 SES) at 6 months, and 24% (5 of 21 SES) at 12 months. CONCLUSIONS: Additional neointimal coverage was observed between 6 and 12 months, with a small increase in the neointimal thickness. The incidence of complete coverage, however, was still low at 12 months. These findings suggest delayed neointimalization on SES.

Pioglitazone reduces the necrotic-core component in coronary plaque in association with enhanced plasma adiponectin in patients with type 2 diabetes mellitus.

BACKGROUND: Pioglitazone has a preventive effect on cardiovascular disease, but its ability to stabilize coronary plaque is unknown. METHODS AND RESULTS: A prospective, randomized trial was conducted in 54 patients with type 2 diabetes and stable angina pectoris, randomly assigned to either a pioglitazone group or control group. Non-culprit, angiographically mild-to-moderate obstructive lesions were examined with virtual histology intravascular ultrasound (VH-IVUS) at coronary intervention and 6 months later. In total, 42 lesions of 22 patients in the pioglitazone group and 44 lesions of 24 patients in the control group were analyzed. After 6 months, patients in the pioglitazone group had significantly improved blood sugar, high-sensitivity C-reactive protein, and plasma adiponectin levels. VH-IVUS analysis revealed that, although the total plaque-to-vessel volume was not changed in either group, the necrotic-core area had significantly decreased in the pioglitazone group (-4.6+/-5.9% vs 1.1+/-9.3%, P=0.001). There was a significant inverse correlation between the change in plasma adiponectin levels and the change in necrotic-core area (r=-0.46, P<0.0001). CONCLUSIONS: Pioglitazone may stabilize coronary plaque by reducing the necrotic-core component, in association with enhanced plasma adiponectin levels.

Very late thrombosis of sirolimus-eluting stent due to late malapposition: serial observations with optical coherence tomography.

A 54 years old man underwent directional coronary atherectomy in segment 7 with a partial deep-cut injury. A sirolimus-eluting stent (SES) was implanted at the restenosed post-atherectomy lesion. Six months after SES implantation, intravascular ultrasound (IVUS) examination revealed slight vessel enlargement although there were no malapposed struts. Optical coherence tomography (OCT) revealed partial stent malapposition. Ticlopidine was discontinued 3 months after SES implantation, but aspirin was continued. Twenty-nine months after SES implantation, after discontinuing aspirin for 7 days for colon polypectomy, the patient suffered an acute myocardial infarction at the SES implantation site. IVUS revealed further positive vessel remodeling and slight stent malapposition and OCT revealed extension of the previous stent malapposition and ulcer-like appearance around the stent struts. This case demonstrates that even a small partial SES malapposition that can be detected only by OCT has the potential to enlarge over time and the late malapposition may result in late thrombosis when anti-platelet therapy is discontinued.

Feasibility of combined use of intravascular ultrasound radiofrequency data analysis and optical coherence tomography for detecting thin-cap fibroatheroma.

AIMS: To evaluate the feasibility of the combined use of virtual histology (VH)-intravascular ultrasound (IVUS) and optical coherence tomography (OCT) for detecting in vivo thin-cap fibroatheroma (TCFA). METHODS AND RESULTS: In 56 patients with angina, 126 plaques identified by IVUS findings were analysed using both VH-IVUS and OCT. IVUS-derived TCFA was defined as an abundant necrotic core (>10% of the cross-sectional area) in contact with the lumen (NCCL) and %plaque-volume >40%. OCT-derived TCFA was defined as a fibrous cap thickness of <65 microm overlying a low-intensity area with an unclear border. Plaque meeting both TCFA criteria was defined as definite-TCFA. Sixty-one plaques were diagnosed as IVUS-derived TCFA and 36 plaques as OCT-derived TCFA. Twenty-eight plaques were diagnosed as definite-TCFA; the remaining 33 IVUS-derived TCFA had a non-thin-cap and eight OCT-derived TCFA had a non-NCCL (in discord with NCCL visualized by VH-IVUS, mainly due to misreading caused by dense calcium). Based on IVUS findings, definite-TCFA showed a larger plaque and vessel volume, %plaque-volume, higher vessel remodelling index, and greater angle occupied by the NCCL in the lumen circumference than non-thin-cap IVUS-derived TCFA. Conclusion Neither modality alone is sufficient for detecting TCFA. The combined use of OCT and VH-IVUS might be a feasible approach for evaluating TCFA.

Relation between plasma adiponectin, high-sensitivity C-reactive protein, and coronary plaque components in patients with acute coronary syndrome.

The present study investigated the relation between plasma high-sensitivity C-reactive protein (hs-CRP) and adiponectin and coronary plaque components in patients with acute coronary syndrome (ACS). Previous studies showed a pivotal role of inflammation in the progression of atherosclerosis and the prognostic value of several biomarkers. However, relations among inflammatory biomarkers and plaque characteristics were unknown. Ninety-three culprit plaques (ACS n = 50, non-ACS n = 43) and 56 nonculprit plaques (ACS n = 28, non-ACS n = 28) were analyzed using Virtual Histology intravascular ultrasound to examine relations among plasma hs-CRP, adiponectin, and ratios of each coronary plaque component. Plasma adiponectin was significantly lower and plasma hs-CRP was significantly higher in patients with than without ACS. Culprit plaques in patients with ACS had greater amounts of necrotic core plaque than those in patients without ACS. There was an inverse relation between serum hs-CRP and adiponectin with regard to necrotic core ratio in both culprit and nonculprit lesions in patients with ACS, but not those without ACS. In conclusion, increased plasma hs-CRP and hypoadiponectinemia might be related to the progression of ACS.

Catheter-based transcoronary myocardial hypothermia attenuates arrhythmia and myocardial necrosis in pigs with acute myocardial infarction.

OBJECTIVES: This study evaluated the efficacy of catheter-based transcoronary myocardial hypothermia (CTMH) in pigs with acute myocardial ischemia. BACKGROUND: Although it has been suggested that hypothermia therapy can attenuate myocardial necrosis, few applications have been accepted for clinical use. METHODS: This study comprises 2 substudies. In both studies, pigs underwent 60 min of coronary occlusion and 180 min of reperfusion. In study 1, after 15 min of coronary occlusion with an over-the-wire-type balloon (OTWB), pigs in the hypothermia group (H) (n = 13) were directly infused with 4 degrees C saline into the coronary artery through the OTWB wire lumen (2.5 ml/min) for 60 min. Pigs in the normothermia group (N) (n = 15) received the same amount of 36.5 degrees C saline. In study 2, pigs in the hypothermia-reperfusion group (HR) (n = 5) were infused with 4 degrees C saline through the infusion catheter (8 ml/min) for 30 min with a later start (60 min after coronary occlusion), whereas simple reperfusion was used for the reperfusion group (R) (n = 6). RESULTS: Catheter-based transcoronary myocardial hypothermia was successful in both studies. In study 1, CTMH significantly decreased ventricular arrhythmia and the ratio of necrosis to ischemic risk area (H: 9 +/- 2%; N: 36 +/- 4%; p < 0.0001) with a significant reduction of enzyme leaks. In study 2, CTMH tended to reduce the ratio of necrosis (HR: 33 +/- 2%; R: 45 +/- 5%; p = 0.08). In both studies, CTMH significantly suppressed the increase of 8-iso-prostaglandin F(2alpha) while preserving the coronary flow reserve. CONCLUSIONS: Catheter-based transcoronary myocardial hypothermia reduced myocardial necrosis while preserving coronary flow reserve, due, in part, to attenuation of oxidative stress.

Neointimal coverage of sirolimus-eluting stents at 6-month follow-up: evaluated by optical coherence tomography.

AIMS: Since the intravascular ultrasound (IVUS) cannot detect neointimal layers in the majority of sirolimus-eluting stents (SES) at the chronic phase, it is still controversial to what extent SES remain uncovered. However, optical coherence tomography (OCT) with excellent resolution may be able to detect thinner neointima. METHODS AND RESULTS: A total of 34 patients (57 SES) underwent OCT and IVUS evaluations at 6-month follow-up. The thickness of neointima on each SES strut cross-section and strut apposition to the vessel wall was evaluated. By OCT evaluation, the median (25th, 75th percentiles) neointima thickness was 52.5 microm (28.0 microm, 147.6 microm) and the prevalence of struts covered by thin neointima undetectable by IVUS was 64%. The average rate of neointima-covered struts in an individual SES was 89%. Nine SES (16%) showed full coverage by neointima, whereas the remaining stents had partially uncovered strut lesions. Among the 6840 struts visualized by OCT in all of the SES, 79 struts showed malapposition without neointimal coverage, and were frequently observed in the areas of SES overlap. CONCLUSION: At 6 months, most of the SES were covered with thin neointima, but few showed full coverage.

[Relationship between high sensitive C-reactive protein and coronary plaque component in patients with acute coronary syndrome: Virtual Histology study].

OBJECTIVES: Elevated circulating C-reactive protein (CRP)is commonly observed in patients with acute coronary syndrome(ACS), suggesting enhanced inflammation in vulnerable plaques. However, few data are available on the relationship between the levels of CRP and the histological composition of coronary plaque. We investigated the relationship between plasma high sensitive CRP level and coronary plaque component with Virtual Histology intravascular ultrasound (VH-IVUS). METHODS: Twenty eight patients with ACS and 37 patients with non-ACS were enrolled in the study. Plasma high sensitve CRP levels were measured before catheterization. A total of 125 lesions (ACS; 24 culprit lesions, 30 non-culprit lesions, non-ACS; 34 culprit lesions, 37 non-culprit lesions)underwent IVUS volumetric investigation, and the volume of plaque and media were calculated. Spectral analysis of IVUS radiofrequency data was performed with VH software, and plaque and media were classified into fibrous, fibro-fatty, dense calcium, and necrotic core elements. RESULTS: Although the plasma high sensitive CRP level in patients with ACS was higher than that in those with non-ACS (0.26 +/- 0.2 vs 0.15 +/- 0.17 mg/dl, p < 0.05), necrotic core volume was not different between the two groups(11.7 +/- 7.3 vs 12.3 +/- 7.2mm3/cm, p = 0.71). There was a positive correlation between high sensitve CRP and necrotic core volume in patients with ACS, not only in culprit lesions (p = 0.0004, r2 = 0.564) but also in non-culprit lesions (p = 0.0008, r2 = 0.473), whereas patients with non-ACS showed no correlations. CONCLUSIONS: IVUS spectral analysis revealed that elevated plasma high sensitve CRP level was correlated with necrotic core volume in patients with ACS, both in culprit and non-culprit lesions, suggesting enhanced vascular inflammation.