Masayuki Takahara

Resting multilayer 2D speckle-tracking transthoracic echocardiography for the detection of clinically stable myocardial ischemic segments confirmed by invasive fractional flow reserve. Part 1: Vessel-by-vessel analysis.

PURPOSE To detect stable ischemic left ventricular (LV)-segments confirmed via invasive fractional flow reserve (FFR) by quantitative longitudinal-strain (LS) determined using resting multilayer TTE. METHODS A retrospective analysis of 39 stable patients (32 males; 65.8±11.9years) with 46 coronary arteries with ≥50% stenosis confirmed by invasive coronary angiography who underwent invasive FFR measurement and TTE (Vivid E9, GE). On TTE, regional LS (absolute values) were calculated in whole, endocardial, and epicardial layers perfused by stenotic coronary arteries. RESULTS Of the 46 vessels, FFR values of <0.75, ≥0.75, ≤0.80 and >0.80 were observed in 17, 29, 27 and 19 vessels, respectively. In a vessel-by-vessel analysis, the whole-layer and endocardial LS were significantly smaller in LV-segments perfused by vessels with an FFR<0.75 than in those with an FFR≥0.75, but epicardial LS was not. In ROC curves, the best cutoff values of whole-layer, endocardial and epicardial LS were, respectively, 14.0% (sensitivity, 94%; specificity 38%; area under the curve, 0.685), 10.0% (47%; 86%; 0.664) and 14.0% (100%; 24%; 0.640) to detect LV-segments with an FFR<0.75; and 14.0% (82%; 37%; 0.561), 10.0% (33%; 84%; 0.573), and 14.0% (89%; 21%; 0.538) to detect LV-segments with an FFR≤0.80. CONCLUSION For stable subjects with coronary arteries with ≥50% stenosis, the regional whole-layer and endocardial LS were significantly smaller in LV-segments perfused by vessels with an FFR<0.75 than in those with an FFR≥0.75, but epicardial LS was not; and that the whole-layer and endocardial LS had a modest diagnostic efficiency in identifying LV-segments perfused by vessels with an FFR<0.75.

Increased platelet inhibition after switching from maintenance clopidogrel to prasugrel in Japanese patients with stable coronary artery disease.

BACKGROUND The pharmacodynamic effects of changing from standard-dose clopidogrel to low-dose (3.75 mg) prasugrel in Japanese patients are largely unknown. METHODSANDRESULTS A total of 53 consecutive Japanese patients with stable coronary artery disease (CAD) who received aspirin and clopidogrel were enrolled. Clopidogrel was switched to 3.75 mg prasugrel. At day 14, prasugrel was switched to 75 mg clopidogrel. Platelet reactivity was measured using the VerifyNow assay at baseline, day 14, and day 28. VerifyNow P2Y12 reaction units (PRU) >208 was defined as high on-treatment platelet reactivity (HPR). The prevalence of HPR (18.9% vs. 41.5% vs. 44.2%, P<0.001) and the PRU level (154.3±54.2 vs. 196.2±55.5 vs. 194.6±55.8, P<0.001) were significantly lower on prasugrel maintenance therapy compared with the clopidogrel therapy before and after switching. The CYP2C19 genotypes that account for the 3 phenotypes (ie, extensive metabolizer, intermediate metabolizer, and poor metabolizer) had a significant impact on platelet reactivity with clopidogrel (174.9±54.0 vs. 193.1±56.5 vs. 240.6±25.4 PRU, P<0.001) but not prasugrel (147.0±51.9 vs. 147.5±58.3 vs. 184.4±38.3 PRU, P=0.15). CONCLUSIONS Low-dose prasugrel achieves stronger platelet inhibition than clopidogrel in Japanese patients with stable CAD.

Resting multilayer 2D speckle-tracking TTE for detection of ischemic segments confirmed by invasive FFR part-2, using post-systolic-strain-index and time from aortic-valve-closure to regional peak longitudinal-strain

PURPOSE This study evaluated the post-systolic strain index (PSI), and the time interval between aortic valve closure (AVC) and regional peak longitudinal strain (PLS), measured by transthoracic echocardiography (TTE), for detection of left ventricular (LV) myocardial ischemic segments confirmed by invasive fractional flow reserve (FFR). MATERIALS AND METHODS 39 stable patients (32 males; 65.8±11.9years) with 46 coronary arteries at ≥50% stenosis on invasive coronary angiography underwent 2D speckle tracking TTE (Vivid E9, GE Healthcare) and invasive FFR measurements. PSI, AVC and regional PLS in each LV segment were calculated. RESULTS FFR ≤0.80 was detected in 27 LV segments. There were no significant differences between segments supplied by FFR ≤0.80 and FFR >0.80 vessels in either PSI or the time interval between AVC and regional PLS. To identify LV segments±FFR ≤0.80, the receiver operator characteristic (ROC) curves for PSI, and the time interval between AVC and regional PLS had areas under the curve (AUC) values of 0.58 and 0.57, respectively, with best cut-off points of 12% (sensitivity 70.4%, specificity 57.9%) and 88ms (sensitivity 70.4%, specificity 52.6%), respectively, but the AUCs were not statistically significant. CONCLUSION In stable coronary artery disease patients with ≥50% coronary artery stenosis, measurement of PSI, and the time interval between AVC and regional PLS, on resting TTE, enabled the identification of LV segments with FFR ≤0.80 using each appropriate threshold for PSI, and the time interval between AVC and regional PLS, with reasonable diagnostic accuracy. However, the AUC values were not statistically significant.

Comparison of 3-dimensional and 2-dimensional quantitative coronary angiography and intravascular ultrasound for functional assessment of coronary lesions

BACKGROUND Three-dimensional quantitative coronary angiography (3D-QCA) reportedly allows more accurate delineation of true vessel geometry when compared with standard two-dimensional (2D) QCA and has been validated by intravascular ultrasound (IVUS). This study sought to compare diagnostic efficiency of 2D- and 3D-QCA, and IVUS in identifying hemodynamically significant coronary stenoses as determined by fractional flow reserve (FFR). METHODS Forty-two lesions in 40 patients were assessed by FFR, IVUS, and 2D- and 3D-QCA. Correlations between FFR values and anatomical parameters obtained by 2D- and 3D-QCA and IVUS were analyzed. The receiver operating characteristic (ROC) curves were used to compare the diagnostic accuracy of the parameters for predicting FFR≤0.80. RESULTS Mean FFR value was 0.75±0.13. FFR≤0.80 was observed in 28 lesions (67%). Of IVUS measurements, minimum lumen area (MLA) well correlated with FFR values (r=0.71, p<0.001). Of 3D- and 2D-QCA measurements, minimum lumen diameter (MLD) correlated best with FFR values (r=0.79, p<0.01; r=0.68, p<0.01, respectively), followed by MLA (r=0.76, p<0.01; r=0.67, p<0.01, respectively). The area under the ROC curve for 3D-QCA MLD was greater than those for 2D-QCA MLD (p=0.03) and 2D-QCA MLA (p=0.03). On the other hand, the AUC for 3D-QCA MLD, 3D-QCA MLA, and IVUS MLA were not significantly different. CONCLUSIONS 3D-QCA is more useful than 2D-QCA and possibly comparable to IVUS in the assessment of functional stenosis severity. When FFR is not available, 3D-QCA MLA and MLD may assist in the assessment of functional severity of intermediate lesions.

Giant pulmonary trunk with Eisenmenger flow through patent ductus arteriosus

Article history: Received 16 November 2015 Accepted 22 November 2015 Available online 23 November 2015 sure of approximately 100 mmHg (Fig. 3). The interventricular septum was displaced towards the LV in systole and diastole, indicative of RV pressure and volume load, respectively (Fig. 3). Atrial and ventricular septal defects were not observed. To evaluate the cause of RV volume and pressure load, an ECG-gated wide-volume conventional scan using 320 slice CT (Aquilion one,

REGIONAL MULTI-LAYER STRAIN MEASUREMENTS USING TRANSTHORACIC ECHOCARDIOGRAM WITH EXERCISE STRESS CAN DETECT CLINICALLY STABLE MYOCARDIAL ISCHEMIC SEGMENTS

We investigated whether multi-layer regional longitudinal strain (LS) measurement on transthoracic echocardiogram (TTE) with exercise stress can detect functional myocardial ischemic segments, as confirmed by fractional flow reserve (FFR), in patients with coronary artery disease. This is a

THE RATIO OF ENDOCARDIAL LONGITUDINAL STRAIN JUST AFTER EXERCISE STRESS TO THAT AT REST IS USEFUL IN DETECTING FUNCTIONAL MYOCARDIAL ISCHEMIC SEGMENTS IN STABLE PATIENTS WITH CORONARY ARTERY DISEASE

We investigated whether multi-layer regional longitudinal strain (LS) measurement on transthoracic echocardiogram (TTE) with exercise stress can detect functional myocardial ischemic segments in patients with coronary artery disease. We examined prospectively 46 coronary arteries in 16 stable

A NOVEL THREE-DIMENSIONAL MYOCARDIAL STRAIN PARAMETERS ON RESTING SPECKLE TRACKING TTE COULD DETECT STABLE LV MYOCARDIAL ISCHEMIC SEGMENTS CONFIRMED BY INVASIVE FRACTIONAL FLOW RESERVE

Parameters derived from 3D myocardial strain on resting speckle tracking TTE, including area (AS), longitudinal (LS), circumferential (CS) and radial strain (RS) may be useful to detect ischemic left ventricular (LV) myocardium confirmed by invasive fractional flow reserve (FFR). This is a

BEST POST-SYSTOLIC SHORTENING TTE PARAMETERS FOR DETECTION OF LEFT VENTRICULAR ISCHEMIC SEGMENTS DETERMINED BY INVASIVE FRACTIONAL FLOW RESERVE

A post-systolic strain index (PSI) >20% and time from aortic valve closure (AVC) to peak strain >90 msec have been reported as parameters of post systolic shortening (PSS) assessed by 2D speckle tracking transthoracic echocardiogram (TTE) (Vivid E9, GE). In stable coronary artery disease subjects

DETERMINATION OF QUANTITATIVE POST-SYSTOLIC STRAIN INDEX THRESHOLD ASSESSED BY TWO-DIMENSIONAL SPECKLE TRACKING ECHOCARDIOGRAPHY FOR DETECTION OF MYOCARDIAL ISCHEMIC SEGMENTS CONFIRMED ON INVASIVE FRACTIONAL FLOW RESERVE

Post-systolic shortening (PSS) is myocardial contraction after aortic valve closure and has been proposed as a marker of myocardial ischemia, but its diagnosis is subjective. We determined quantitative threshold of post-systolic strain index (PSI) as a parameter of PSS assessed by 2D speckle