Utility of Superb Microvascular Imaging in the Assessment of Foot Perfusion in Patients with Critical Limb Ischemia.

(1) Background: Although the ankle-brachial index (ABI) and skin perfusion pressure (SPP) are commonly used to evaluate the peripheral circulation in critical limb ischemia (CLI), they often cannot be performed on sore areas. We investigated the utility of superb microvascular imaging (SMI) for assessing foot perfusion in CLI patients. (2) Methods: We measured the SMI-based vascular index (SMI-VI) at six sites in the foot before and after endovascular treatment (EVT) in 50 patients with CLI who underwent EVT of the superficial femoral artery and compared the results with SPP values and the ABI. (3) Results: SMI visualized foot perfusion in all subjects in accordance with the angiosome, including the toe areas, while the ABI was unmeasurable in three patients on hemodialysis and SPP failed in four patients. SMI-VI values were significantly lower in the CLI group than in controls, and the plantar SMI-VI had the highest diagnostic performance for CLI (sensitivity 88.6%, specificity 95.6%). After EVT, the increase in the SMI-VI was positively correlated with the increase in SPP but not that in the ABI, implying that the SMI-VI reflects foot microcirculation. (4) Conclusions: SMI enables the visualization and quantification of foot microcirculation based on the angiosome. SMI has high utility as a tool for assessing foot perfusion in CLI.

Revised estimates of leprosy disability weights for assessing the global burden of disease: A systematic review and individual patient data meta-analysis.

BACKGROUND: Leprosy is a chronic bacterial infection caused by Mycobacterium leprae, which may lead to physical disability, stigma, and discrimination. The chronicity of the disease and disabilities are the prime contributors to the disease burden of leprosy. The current figures of the disease burden in the 2017 global burden of disease study, however, are considered to be under-estimated. In this study, we aimed to systematically review the literature and perform individual patient data meta-analysis to estimate new disability weights for leprosy, using Health-Related Quality of Life (HRQOL) data. METHODOLOGY/PRINCIPAL FINDINGS: The search strategy included all major databases with no restriction on language, setting, study design, or year of publication. Studies on human populations that have been affected by leprosy and recorded the HRQOL with the Short form tool, were included. A consortium was formed with authors who could share the anonymous individual-level data of their study. Mean disability weight estimates, sorted by the grade of leprosy disability as defined by WHO, were estimated for individual participant data and pooled using multivariate random-effects meta-analysis. Eight out of 14 studies from the review were included in the meta-analysis due to the availability of individual-level data (667 individuals). The overall estimated disability weight for grade 2 disability was 0.26 (95%CI: 0.18-0.34). For grade 1 disability the estimated weight was 0.19 (95%CI: 0.13-0.26) and for grade 0 disability it was 0.13 (95%CI: 0.06-0.19). The revised disability weight for grade 2 leprosy disability is four times higher than the published GBD 2017 weights for leprosy and the grade 1 disability weight is nearly twenty times higher. CONCLUSIONS/SIGNIFICANCE: The global burden of leprosy is grossly underestimated. Revision of the current disability weights and inclusion of disability caused in individuals with grade 0 leprosy disability will contribute towards a more precise estimation of the global burden of leprosy.

[Significant Changes Associated with the Transition from Outsourcing to In-hospital Therapeutic Drug Monitoring of Novel Antiepileptics].

For many of the novel antiepileptics, immunoassays, used for routine therapeutic drug monitoring (TDM), cannot be used. We could monitor eight novel antiepileptics using an LC/MS method since July 2017. The purpose of this study was to evaluate the significant changes associated with the transition from outsourcing to in-hospital monitoring of novel antiepileptics. The number of measurements of novel antiepileptics was significantly increased during the first (p<0.01) and second (p<0.001) years of in-hospital monitoring as compared to that one year prior to in-hospital monitoring which was outsourced. The proportion of measurements of novel antiepileptics to all antiepileptics was 19.7%, 31.1%, and 38.4% during outsourcing, and first, and second years of in-hospital monitoring, respectively. The measurement cost was significantly reduced during the first (p<0.001) and second (p<0.001) years of in-hospital monitoring as compared to that during outsourcing. In addition, the revenue from TDM of antiepileptic drugs was significantly increased during the first (p<0.05) and second (p<0.01) years of in-hospital monitoring as compared with that during outsourcing. In conclusion, the switch from outsourcing to in-hospital monitoring led to an increase in the number of orders, a reduction in the measurement-related expenses of novel antiepileptics, and an increase in the revenue from TDM of antiepileptic drugs, which could promote the proper use of novel antiepileptics through TDM.

Superiority of novel automated assessment of aortic annulus by intraoperative three-dimensional transesophageal echocardiography in patients with severe aortic stenosis: Comparison with conventional cross-sectional assessment.

BACKGROUND: Previous studies have demonstrated that three-dimensional (3D) transesophageal echocardiography (TEE) is an alternative to multi-detector computed tomography (MDCT) for aortic valve sizing in transcatheter aortic valve replacement (TAVR). However, conventional cross-sectional analysis of aortic annulus by 3D TEE has some limitations such as lengthy analytical time. A novel software for automated valve measurement has been developed for 3D TEE. We evaluated the accuracy and analytical time of aortic annular measurements using this novel automated software in the clinical setting. METHODS: We retrospectively studied 43 patients with symptomatic severe aortic stenosis (AS) who underwent TAVR. All patients underwent intraoperative TEE and MDCT. We measured aortic annular area by automated, semi-automated, and cross-sectional methods using 3D TEE datasets. These measurements were compared to the corresponding MDCT reference values. We also compared the analytical time of the three methods. RESULTS: Automated and semi-automated analyses required significantly shorter analytical time compared to cross-sectional analysis (automated: 30.1±5.79s, semi-automated: 74.1±15.0s, manual: 81.8±18.5s, p<0.05). Compared to MDCT measurement (393.7±81.0mm2), annular areas measured by automated and cross-sectional methods were significantly smaller (automated: 380.6±77.1mm2, cross-sectional: 374.7±76.8mm2, p<0.05), while that obtained by semi-automated method was not significantly different (387.7±75.8mm2). Annular areas determined by semi-automated and cross-sectional analyses had narrower limits of agreement (LOA) with MDCT measurements, compared to automated analysis (automated: -68.6 to 94.7mm2, semi-automated: -48.3 to 60.2mm2, cross-sectional: -40.0 to 77.9mm2). Measurements by all three methods using 3D TEE showed high correlation with MDCT measurement (automated: r=0.86, semi-automated: r=0.94, cross-sectional: r=0.93). CONCLUSIONS: For aortic annular measurements using 3D TEE in AS patients, semi-automated analysis using the novel automated software reduced analytical time while maintaining similar accuracy compared to the conventional cross-sectional analysis. This automated software may have acceptable feasibility in the clinical setting.

18F-FPYBF-2, a new F-18 labelled amyloid imaging PET tracer: biodistribution and radiation dosimetry assessment of first-in-man 18F-FPYBF-2 PET imaging.

OBJECTIVE: Recently, a benzofuran derivative for the imaging of ß-amyloid plaques, 5-(5-(2-(2-(2-18F-fluoroethoxy)ethoxy)ethoxy)benzofuran-2-yl)- N-methylpyridin-2-amine (18F-FPYBF-2) has been validated as a tracer for amyloid imaging and it was found that 18F-FPYBF-2 PET/CT is a useful and reliable diagnostic tool for the evaluation of AD (Higashi et al. Ann Nucl Med, https://doi.org/10.1007/s12149-018-1236-1 , 2018). The aim of this study was to assess the biodistribution and radiation dosimetry of diagnostic dosages of 18F-FPYBF-2 in normal healthy volunteers as a first-in-man study. METHODS: Four normal healthy volunteers (male: 3, female: 1; mean age: 40 ± 17; age range 25-56) were included and underwent 18F-FPYBF-2 PET/CT study for the evaluation of radiation exposure and pharmacokinetics. A 10-min dynamic PET/CT scan of the body (chest and abdomen) was performed at 0-10 min and a 15-min whole-body static scan was performed six times after the injection of 18F-FPYBF-2. After reconstructing PET and CT image data, individual organ time-activity curves were estimated by fitting volume of interest data from the dynamic scan and whole-body scans. The OLINDA/EXM version 2.0 software was used to determine the whole-body effective doses. RESULTS: Dynamic PET imaging demonstrated that the hepatobiliary and renal systems were the principal pathways of clearance of 18F-FPYBF-2. High uptake in the liver and the gall bladder, the stomach, and the kidneys were demonstrated, followed by the intestines and the urinary bladder. The ED for the adult dosimetric model was estimated to be 8.48 ± 1.25 µSv/MBq. The higher absorbed doses were estimated for the liver (28.98 ± 12.49 and 36.21 ± 15.64 µGy/MBq), the brain (20.93 ± 4.56 and 23.05 ± 5.03µ Gy/MBq), the osteogenic cells (9.67 ± 1.67 and 10.29 ± 1.70 µGy/MBq), the small intestines (9.12 ± 2.61 and 11.12 ± 3.15 µGy/MBq), and the kidneys (7.81 ± 2.62 and 8.71 ± 2.90 µGy/MBq) for male and female, respectively. CONCLUSIONS: The ED for the adult dosimetric model was similar to those of other agents used for amyloid PET imaging. The diagnostic dosage of 185-370 MBq of 18F-FPYBF-2 was considered to be acceptable for administration in patients as a diagnostic tool for the evaluation of AD.

Validity of Ultrasound Lung Comets for Assessment of the Severity of Interstitial Pneumonia.

OBJECTIVES: Ultrasound (US) lung comets are often observed in patients with interstitial lung disease or congestive heart failure, but few studies have explored the clinical importance of US lung comets in patients with the former condition. We explored whether the US lung comet number could be used to assess the severity of interstitial pneumonia. METHODS: Forty stable patients with interstitial pneumonia were examined. Lung comets evident on transthoracic US imaging in 12 selected regions of the posterior chest wall were analyzed. We defined lung comets accompanied by thickened and irregular pleural lines as interstitial US lung comets; these predominated in patients with interstitial pneumonia. The total number of interstitial US lung comets was correlated with the data from chest high-resolution computed tomography, pulmonary function tests, serologic tests, and the 6-minute walk test. RESULTS: The 40 patients included 16 with idiopathic pulmonary fibrosis and 24 with nonspecific interstitial pneumonia. Thirty-four patients had interstitial US lung comets, which were more common in the lower than the upper lung area. Good correlations were evident between the lung comet number and the extent of the reticular pattern on chest high-resolution computed tomography (r = 0.710; P < .01), predicted forced vital capacity (r = -0.614; P < .01), and lung diffusion capacity for carbon monoxide (r = -0.577; P < .01). Notably, the lung comet number had a strong negative correlation with the percutaneous oxygen saturation level after the 6-minute walk test (r = -0.751; P < .01). CONCLUSIONS: The number of interstitial US lung comets evident on transthoracic US imaging may be a valuable marker of disease severity in patients with interstitial pneumonia.

[An example of the socio-economic rehabilitation program for ex-leprosy patients in Vietnam and its evaluation by the patients].

One of the leprosy treatment centers (hospital X) in Vietnam offers loan programs to start work as part of the socio-economic rehabilitation program for ex-leprosy patients. The aim of this study is to examine and evaluate the contents of the program from the ex-leprosy patients' perspective. The interview group was sub-divided into three groups: male/female and the younger group. A focus group interview method was used to collect qualitative data. The participant program group revealed that their income increased and their health condition improved; moreover, they evaluated the program highly as they can borrow business loan at no interest. Meanwhile, the participants were challenged with a few problems: the frequency in the illness of the livestock and the forcible discounting in the livestock's price by the customers who use the excuse that the livestock has been raised by ex-leprosy patients. The younger group had concerns regarding the program; they were worried about the repayment of the business loan. Both groups noted points to improve the current program especially in terms of changing the loan repayment schedule and loan volume. Therefore, the program has to be adapted to the needs of ex-leprosy patients.

[Importance of monitoring the drug dosage and treatment duration for the management of tuberculosis patients at public health centers].

PURPOSE: On the basis of actual field data, we investigated the importance of monitoring the drug dosage and treatment duration for the supportive care of patients with tuberculosis who were being treated at public health centers. PATIENTS & METHODS: Data of the drug dosage of principal anti-tuberculosis drugs and the treatment duration for the registered patients with tuberculosis at the Shinjuku-ku Public Health Center were analyzed. RESULTS: The actual dosage of rifampicin and isoniazid according to the "recommended" dosage was administered to 57.3% (67/117) and 82.0% (114/139), respectively, patients with tuberculosis registered at the Shinjuku-ku Public Health Center. In contrast, in patients with tuberculosis who were treated at a highly specialized tuberculosis hospital, the rates were 81.0% (98/121) and 93.5% (86/92), respectively; for both drugs, the rates were significantly higher in this hospital than in the Shinjuku-ku Public Health Center. For the treatment duration, of 92 patients registered at the Shinjuku-ku Public Health Center who could have completed standard treatment in the standard duration, the actual treatment durations were shorter than the standard duration in 15.2% of the patients (14/92; -32 to -1 days), and longer than the standard duration in 77.2% (71/92; 2 to 146 days); the total superfluous treatment days for the latter 71 patients were 1,877 days. The treatment durations were more than 2 weeks shorter or longer than the standard duration for 31 patients, and in 71.0% (22/31) of these patients, no specific reason could be determined as to why the treatment durations were not standard. CONCLUSION: In a significant number of patients, the drug dosage and treatment duration were not according to the standard values. By using this data about the management of the drug dosage and treatment duration for the supportive care of patients with tuberculosis treated at public health centers, we may improve quality of the provided supportive care.

Diagnostic accuracy and cost-effectiveness of a pocket-sized transthoracic echocardiographic imaging device.

BACKGROUND: The recently introduced pocket-sized portable transthoracic echocardiography (pTTE) is accurate for measurement of cardiac chamber size and function as well as for assessment of valvular regurgitation. This study aimed to compare the diagnostic accuracy of the pocket-sized pTTE with the standard TTE (sTTE) and assess its cost-effectiveness. HYPOTHESIS: The use of pocket-sized pTTE, as an initial screening tool, may be feasible, accurate and cost-effective in the diagnostic strategy of cardiac abnormalities. METHODS: The study subjects were 200 patients scheduled for sTTE and an electrocardiogram (ECG). Each patient underwent pTTE examination with the Vscan (GE Medical Systems, Milwaukee, WI) immediately after sTTE. The findings of pTTE and the ECG were compared with the results of sTTE. Cost-effectiveness was calculated. RESULTS: There was a strong agreement in the detection of abnormal findings between pTTE and sTTE (agreement = 90%), whereas the agreement between the ECG and sTTE was 65%. When pTTE or the ECG was used as an initial screening tool prior to sTTE, similar cost reduction was obtained (approximately 30%) by reducing the number of referrals for sTTE. However, the negative predictive value of a diagnostic strategy with pTTE (92%) was superior to that with an ECG (67%). CONCLUSIONS: This study demonstrates that the pocket-sized pTTE provides accurate detection of cardiac structural and functional abnormalities beyond the ECG. In addition, the use of pTTE as an initial screening tool prior to sTTE is cost-effective, suggesting that the pocket-sized pTTE is poised to alter the current diagnostic strategy in clinical practice.

Impaired renal function is a major determinant of left ventricular diastolic dysfunction: assessment by stress myocardial perfusion imaging.

OBJECTIVE: Relationships between myocardial scintigraphic parameters and renal function have not been fully determined. We investigated correlations between estimated glomerular filtration rate (eGFR) and left ventricular (LV) diastolic function using stress electrocardiographic (ECG)-gated myocardial single photon emission computed tomography (SPECT). METHODS: We enrolled 136 consecutive patients with suspected coronary artery disease (CAD) who were assessed using technetium-99m stress ECG-gated myocardial SPECT. We evaluated SPECT images using 17-segment defect scores graded on a 5-point scale, summed stress score, summed rest score and summed difference score (SDS). The parameters for assessing LV diastolic function were peak filling rate (PFR), 1/3 mean filling rate and time to peak filling. The CAD was defined as SDS ≥2. Chronic kidney disease (CKD) was defined as eGFR <60 mL/min/1.73 m(2). Patients were assigned to the following four groups (no CAD/no CKD: control group, n = 68; CAD/no CKD: CAD group, n = 24; no CAD/CKD: CKD group, n = 34; CAD/CKD: CAD + CKD group, n = 10). RESULTS: The PFR was significantly impaired after stress in the CKD and CAD + CKD groups compared with controls (p < 0.001 for both). Furthermore, PFR at rest positively correlated with eGFR (r = 0.29, p < 0.001) and inversely correlated with SDS (r = -0.18, p < 0.05). Multivariate stepwise regression analysis independently associated eGFR with PFR (ß coefficient = 0.260, p = 0.002). CONCLUSIONS: Our data suggest that impaired renal function is a significant determinant of LV diastolic dysfunction in patients with suspected CAD.

Assessment of the aroma impact of major odor-active thiols in pan-roasted white sesame seeds by calculation of odor activity values.

Eleven odor-active thiols, namely, 2-methyl-1-propene-1-thiol, (Z)-3-methyl-1-butene-1-thiol, (E)-3-methyl-1-butene-1-thiol, (Z)-2-methyl-1-butene-1-thiol, (E)-2-methyl-1-butene-1-thiol, 2-methyl-3-furanthiol, 3-mercapto-2-pentanone, 2-mercapto-3-pentanone, 4-mercapto-3-hexanone, 3-mercapto-3-methylbutyl formate, and 2-methyl-3-thiophenethiol, recently identified in an extract prepared from white sesame seeds, were quantitated in sesame using stable isotope dilution analyses. For that purpose, the following deuterium-labeled compounds were synthesized and used as internal standards in the quantitation assays: [2H6]-2-methyl-1-propene-1-thiol, [2H3]-(E)- and [2H3]-(Z)-2-methyl-1-butene-1-thiol, [2H3]-2-methyl-3-furanthiol, [2H2]-3-mercapto-2-pentanone, [2H3]-4-mercapto-3-hexanone, [2H6]-3-mercapto-3-methylbutyl formate, and [2H3]-2-methyl-3-thiophenethiol. On the basis of the results obtained, odor activity values (OAVs) were calculated as ratio of the concentration and odor threshold of the individual compounds in cooking oil. According to their high OAVs, particularly the 3-methyl-1-butene-1-thiols (OAV: 2400) and the 2-methyl-1-butene-1-thiols (OAV: 960) were identified as the most odor-active compounds in pan-roasted white sesame seeds. These compounds were therefore suggested to be mainly responsible for the characteristic but rather unstable sulfury aroma of freshly pan-roasted white sesame seeds.

Assessment of coronary flow velocity reserve by transthoracic Doppler echocardiography before and after coronary artery bypass grafting.

Little is known about the changes in the coronary flow velocity reserve (CFVR) of the left anterior descending artery (LAD) before and after coronary artery bypass grafting (CABG). The present study aimed to evaluate the feasibility of measuring the CFVR of the LAD using transthoracic Doppler echocardiography before and after CABG. We prospectively measured the CFVR before and after CABG in 56 patients. The flow velocity in the LAD was measured using transthoracic Doppler echocardiography both at rest and during intravenous infusion of adenosine. The CFVR was calculated as the ratio of hyperemic to the basal peak and mean diastolic flow velocities. Coronary angiography was also performed to assess graft patency after CABG in all patients. Furthermore, we compared the differences between the pre- and postoperative CFVR in patients with and without a diffusely diseased LAD (lesion length >2 cm). All grafts were angiographically patent. The postoperative peak and mean CFVR were significantly increased compared to the preoperative peak and mean CFVR (both peak and mean 2.7 ± 0.9 vs 1.5 ± 0.6, respectively; p<0.0001). The preoperative peak CFVR was significantly lower in patients with a diffusely diseased LAD than in those without a diffusely diseased LAD (1.3 ± 0.5 vs 1.6 ± 0.5, respectively; p=0.04). The postoperative peak CFVR of the 2 groups was almost identical (2.5 ± 0.6 vs 2.9 ± 1.0; p=0.07). In conclusion, assessment of the CFVR of the LAD using transthoracic Doppler echocardiography was useful after CABG for confirming graft patency.

Physiologic assessment of coronary artery stenosis without stress tests: noninvasive analysis of phasic flow characteristics by transthoracic Doppler echocardiography.

We evaluated the significance of the diastolic-to-systolic blood flow velocity ratio (DSVR) determined by transthoracic Doppler echocardiography, for a physiologic assessment of the severity of coronary stenosis without stress tests, as compared with thallium 201 single photon emission computed tomography. In 95 patients undergoing thallium 201 single photon emission computed tomography for coronary artery disease, the flow velocity in the distal left anterior descending coronary artery was obtained with transthoracic Doppler echocardiography. The mean and peak DSVR values were calculated using mean and peak coronary flow velocity. DSVR was successfully measured for 82 patients (86.3%), including 33 patients with reversible perfusion defects in the left anterior descending coronary artery territories. For predicting reversible perfusion defects in thallium 201 single photon emission computed tomography, the best cut-off points were 1.5 for mean DSVR (sensitivity 81.8%, specificity 85.7%) and 1.6 for peak DSVR (sensitivity 75.7%, specificity 83.6%). Noninvasive measurement of DSVR with transthoracic Doppler echocardiography provides physiologic estimation of the left anterior descending coronary artery stenosis severity at high success rate, without stress tests.

Comparison of cardiovascular responses between upright and recumbent cycle ergometers in healthy young volunteers performing low-intensity exercise: assessment of reliability of the oxygen uptake calculated by using the ACSM metabolic equation.

OBJECTIVES: To clarify (1) differences in cardiovascular response during low-intensity exercise in the upright versus the recumbent position, and (2) whether the oxygen uptake (V o 2 ) calculated by the American College of Sports Medicine (ACSM) metabolic equation reflects the actual V o 2 at low-intensity testing. DESIGN: Repeated-measures comparison study. SETTING: University research laboratory. PARTICIPANTS: Thirty-one healthy, young volunteers (age, 23+/-2y). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Blood pressure, rate pressure product (RPP), V o 2 , oxygen pulse, carbon dioxide output (V co 2 ), and ventilatory equivalent (V e ) were measured during graded exercise testing using upright and recumbent cycle ergometers. The estimated V o 2 was calculated by using the ACSM metabolic equation. RESULTS: Systolic blood pressure, RPP, V o 2 , oxygen pulse, V co 2 , and V e at 15 or 30W were significantly higher in the recumbent position than in the upright one ( P <.05), however, no significant differences were observed at 50 and 70W. The estimated V o 2 during exercise was significantly higher than the actual one, at every level of intensity, from 15 to 70W ( P <.05). CONCLUSIONS: Cardiovascular responses should be carefully monitored even during low-intensity exercise using a recumbent cycle ergometer. The V o 2 estimated using the ACSM metabolic equation did not reflect the actual V o 2 during low-intensity exercise at 70W or less.

Rapid and accurate noninvasive assessment of global left ventricular systolic function using biplane advanced automated contour tracking method.

BACKGROUND: The advanced automated contour tracking (AACT) method has been newly developed for automated detection of the left ventricular endocardial boundary. Left ventricular ejection fraction (LVEF) may be estimated by applying the AACT method to 2 orthogonal planes of patients even when regional wall-motion abnormalities exist. The purpose of this study was to examine the reliability of the biplane AACT method in the measurement of LVEF in patients with suggested ischemic heart disease with use of quantitative gated single photon emission computed tomography (QGS) as a reference standard. METHODS: The study population consisted of 47 consecutive patients with suggested ischemic heart disease. All patients underwent 2-dimensional echocardiography and QGS. Biplane LVEF from apical 4- and 2-chamber views was measured offline by the AACT method using disk summation method. The accuracy of the AACT method for LVEF measurement was determined in comparison with QGS. RESULTS: In 41 (29 with and 12 without regional wall-motion abnormalities) of 47 patients (87%), automated tracing of the endocardial border was adequately achieved with the AACT method. LVEF measured by the AACT method correlated well with that measured by QGS (y = 0.97x +2.4, r = 0.91). The mean difference between AACT and QGS was 0.6 +/- 5.5% (mean +/- SD). The mean time required for analysis of 1 set of images during 1 cardiac cycle by the AACT method was much shorter than that required by manual tracing method (7 +/- 1 vs 37 +/- 4 seconds, P <.0001). CONCLUSION: The biplane AACT method provides accurate and quick measurement of LVEF in patients even with regional wall-motion abnormalities.

Noninvasive assessment of myocardial ischemia in the left ventricular inferior regions by coronary flow reserve measurement using transthoracic Doppler echocardiography.

OBJECTIVE: The purpose of this study was to evaluate the potential of noninvasive measurement of coronary flow reserve (CFR) by transthoracic Doppler echocardiography (TTDE) for the assessment of myocardial ischemia in the left ventricular (LV) inferior regions. BACKGROUND: Although coronary flow assessment by TTDE has been determined for the assessment of perfusion abnormality in the LV anterior regions, the usefulness of this method has not been well investigated in the LV inferior regions. METHODS: We studied 50 patients (43 men; mean age 60 +/- 9 years) with suggested coronary artery disease. CFR in the posterodescending coronary artery (PDA) was calculated as a ratio of hyperemic to basal peak (peak CFR) and mean (mean CFR) flow velocities in the PDA, which were measured by TTDE. CFR values were compared with the results of exercise 201-thallium single photon emission computed tomography. RESULTS: CFR was successfully measured in 43 of 50 patients (86%). Mean and peak CFR < 2 were shown in 10 of 12 patients with abnormal perfusion in the LV inferior regions, whereas CFR > or = 2 were shown in 30 of 31 patients with normal perfusion. Thus, CFR < 2 in the PDA by TTDE had a sensitivity of 83% and a specificity of 97% for the assessment of perfusion abnormality in the LV inferior regions by 201-thallium single photon emission computed tomography. CONCLUSIONS: CFR in the PDA measured by TTDE provides data equivalent to those obtained by 201-thallium single photon emission computed tomography for myocardial ischemia in the LV inferior regions.

Physiologic assessment of left anterior descending coronary artery stenosis by quantitative intravenous myocardial contrast echocardiography in humans: comparison with exercise single-photon emission computed tomography.

OBJECTIVE: To clarify the potential of quantitative intravenous myocardial contrast echocardiography (MCE) for physiologic assessment of the left anterior descending artery (LAD) stenosis. METHODS: We studied 38 patients with suspected coronary artery disease. MCE was performed by continuous infusion of Levovist and intermittent ultrasonic exposure. Images were obtained from the apical four-chamber view at rest and after dipyridamole infusion. The background-subtracted intensity versus pulsing interval plots were fitted to an exponential function,Y=A(1 e-ss), to obtain the plateau level (A) and rate of rise (ss) of background-subtracted intensity both at rest and after dipyridamole infusion. We compared the results with those of exercise thallium-201 single-photon emission computed tomography (SPECT). RESULTS: Of the 38 patients, 18 patients exhibited redistribution in the LAD territories with SPECT (group A), although 20 did not (group B). The ss reserve (DIP/rest) in group A was significantly lower than those in group B (0.8 +/- 0.5 versus 2.0 +/- 1.1, P < 0.001), while the A reserve did not differ between the two groups (1.2 +/- 0.6 versus 1.0 +/- 0.5, P = NS). The ss reserve <1.1, which was the optimal cutoff value, provided sensitivity of 79% and specificity of 84% for the presence of redistribution in SPECT. CONCLUSIONS: Quantitative intravenous MCE allows us to estimate physiologic severity of the LAD stenosis in the clinical setting.