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Edward P. Shapiro

Bio: Edward P. Shapiro is an academic researcher from Johns Hopkins University. The author has contributed to research in topics: Coronary artery disease & Myocardial infarction. The author has an hindex of 46, co-authored 109 publications receiving 10486 citations. Previous affiliations of Edward P. Shapiro include Johns Hopkins University School of Medicine & National Institutes of Health.


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Journal ArticleDOI
TL;DR: Multidetector CT angiography accurately identifies the presence and severity of obstructive coronary artery disease and subsequent revascularization in symptomatic patients, and the negative and positive predictive values indicate that multidetctor CTAngiography cannot replace conventional coronary angiographic at present.
Abstract: Methods We conducted a multicenter study to examine the accuracy of 64-row, 0.5-mm multidetector CT angiography as compared with conventional coronary angiography in patients with suspected coronary artery disease. Nine centers enrolled patients who underwent calcium scoring and multidetector CT angiography before conventional coronary angiography. In 291 patients with calcium scores of 600 or less, segments 1.5 mm or more in diameter were analyzed by means of CT and conventional angiography at independent core laboratories. Stenoses of 50% or more were considered obstructive. The area under the receiver-operating-characteristic curve (AUC) was used to evaluate diagnostic accuracy relative to that of conventional angiography and subsequent revascularization status, whereas disease severity was assessed with the use of the modified Duke Coronary Artery Disease Index. Results A total of 56% of patients had obstructive coronary artery disease. The patient-based diagnostic accuracy of quantitative CT angiography for detecting or ruling out stenoses of 50% or more according to conventional angiography revealed an AUC of 0.93 (95% confidence interval [CI], 0.90 to 0.96), with a sensitivity of 85% (95% CI, 79 to 90), a specificity of 90% (95% CI, 83 to 94), a positive predictive value of 91% (95% CI, 86 to 95), and a negative predictive value of 83% (95% CI, 75 to 89). CT angiography was similar to conventional angiography in its ability to identify patients who subsequently underwent revascularization: the AUC was 0.84 (95% CI, 0.79 to 0.88) for multidetector CT angiography and 0.82 (95% CI, 0.77 to 0.86) for conventional angiography. A per-vessel analysis of 866 vessels yielded an AUC of 0.91 (95% CI, 0.88 to 0.93). Disease severity ascertained by CT and conventional angiography was well correlated (r = 0.81; 95% CI, 0.76 to 0.84). Two patients had important reactions to contrast medium after CT angiography. Conclusions Multidetector CT angiography accurately identifies the presence and severity of obstructive coronary artery disease and subsequent revascularization in symptomatic patients. The negative and positive predictive values indicate that multidetector CT angiography cannot replace conventional coronary angiography at present. (ClinicalTrials.gov number, NCT00738218.)

1,721 citations

Journal ArticleDOI
TL;DR: Specified regions of the myocardium can be labeled in magnetic resonance (MR) imaging to serve as markers during contraction, thus permitting sampling of the entire contractile phase of the cardiac cycle.
Abstract: Specified regions of the myocardium can be labeled in magnetic resonance (MR) imaging to serve as markers during contraction. The technique is based on locally perturbing the magnetization of the myocardium with selective radio-frequency (RF) saturation of multiple, thin tag planes during diastole followed by conventional, orthogonal-plane imaging during systole. The technique was implemented on a 0.38-T imager and tested on phantoms and volunteers. In humans, tags could be seen 60-450 msec after RF saturation, thus permitting sampling of the entire contractile phase of the cardiac cycle. Tagged regions appear as hypointense stripes, and their patterns of displacement reflect intervening cardiac motion. In addition to simple translation and rotation, complex motions such as cardiac twist can be demonstrated. The effects of RF pulse angle, relaxation times, and heart rate on depiction of the tagged region are discussed.

1,506 citations

Journal ArticleDOI
TL;DR: ALT-711 improves total arterial compliance in aged humans with vascular stiffening, and it may provide a novel therapeutic approach for this abnormality, which occurs with aging, diabetes, and isolated systolic hypertension.
Abstract: Background Arterial stiffening with increased pulse pressure is a leading risk factor for cardiovascular disease in the elderly. We tested whether ALT-711, a novel nonenzymatic breaker of advanced glycation end-product crosslinks, selectively improves arterial compliance and lowers pulse pressure in older individuals with vascular stiffening. Methods and Results Nine US centers recruited and randomly assigned subjects with resting arterial pulse pressures >60 mm Hg and systolic pressures >140 mm Hg to once-daily ALT-711 (210 mg; n=62) or placebo (n=31) for 56 days. Preexisting antihypertensive treatment (90% of subjects) was continued during the study. Morning upright blood pressure, stroke volume, cardiac output, systemic vascular resistance, total arterial compliance, carotid-femoral pulse wave velocity, and drug tolerability were assessed. ALT-711 netted a greater decline in pulse pressures than placebo (−5.3 versus −0.6 mm Hg at day 56; P=0.034 for treatment effect by repeated-measures ANOVA). Systoli...

697 citations

Journal ArticleDOI
TL;DR: Tagging was used to noninvasively quantify left ventricular torsion and circumferential-longitudinal shear (shearCL) in humans and calculated the difference in angular displacement of each epicardial and endocardial tag point at end systole from the systolic position of the corresponding tag point on the basal plane.
Abstract: It has been postulated that rotation of the left ventricular apex with respect to the base is a component of normal systolic function in humans, but it has been difficult to measure it noninvasively. Tagging is a new magnetic resonance imaging technique that labels specific areas of myocardium by selective radio-frequency excitation of narrow planes orthogonal to the imaging plane before acquiring an image. Tags appear as black lines and persist in myocardium for 400-500 msec and, if applied at end diastole, will move with the myocardium through systole. Tagging was used to noninvasively quantify left ventricular torsion and circumferential-longitudinal shear (shearCL) in humans. Eight normal volunteers, aged 24-38 years, were imaged in a 0.38-T iron-core resistive magnet. Five short-axis left ventricular images, positioned to encompass the entire left ventricle (LV), were obtained separately at end systole. Four equiangular radial tags had been applied at end diastole, intersecting the myocardium at eight locations. We calculated the difference in angular displacement of each epicardial and endocardial tag point (a tag point being where the tag crossed the epicardium or endocardium) at end systole from the systolic position of the corresponding tag point on the basal plane. This value was called the torsion angle. From this, shearCL, the angle inscribed on the epicardial or endocardial surface between the systolic tag position, the corresponding basal tag position, and its projection onto the slice of interest could be calculated at 32 points in the left ventricular wall.(ABSTRACT TRUNCATED AT 250 WORDS)

364 citations

Journal ArticleDOI
TL;DR: Untwisting occurs principally during isovolumic relaxation before filling and is markedly enhanced in speed and magnitude by catecholamines, which could represent an important mechanism for the release of potential energy stored in elastic elements during the systolic deformation.
Abstract: BACKGROUND Efficient early diastolic filling is essential for normal cardiac function. Diastolic suction, as evidenced by a decreasing left ventricular pressure during early filling, could result from restoring forces (the release of potential energy stored during systolic deformation) dependent on myofilament relaxation. Although these restoring forces have been envisioned within individual myofibers, recent studies suggest that gross fiber rearrangement involving the connective tissue network occurs easy in diastole. This may lead to the release of potential energy stored during systole and suction-aided filling. METHODS AND RESULTS To establish precisely the timing and extent of restoration of the systolic torsional deformation of the left ventricle with respect to early filling at baseline and with enhanced relaxation, we studied untwisting during control conditions and with catecholamine stimulation. Using noninvasive and nondestructive magnetic resonance tagging, torsional deformation of the left ventricle was measured at 20-msec intervals in 10 open-chest, atrially paced dogs, starting at aortic valve closure. Eight equiangular tags intersected the epicardium and endocardium in three short-axis imaging planes (base, mid, and apex). From the intersection points, epicardial and endocardial circumferential chord and arc lengths were measured and angular twist of mid and apical levels with respect to the base (maximal torsion and its reversal, untwisting) was calculated. Echo-Doppler provided timing of aortic valve closure and of mitral valve opening. Zero torsion was defined at end diastole. Torsion at the apical level reversed rapidly between its maximum and the time immediately after mitral valve opening: from 7.0 +/- 5.8 degrees to 3.2 +/- 5.4 degrees and 12.0 +/- 8.5 degrees to 6.9 +/- 7.8 degrees (mean +/- SD, both p less than 0.01) at the epicardium and endocardium, respectively. During the same period, no significant circumferential segment length changes occurred. As expected, after mitral valve opening, filling resulted in significant circumferential segment lengthening, whereas further reversal of torsion was small and nonsignificant. During dobutamine infusion, torsion at end systole was greater and reversal during isovolumic relaxation was much more rapid and greater in extent (p less than 0.01). Torsion reversed from 11.5 +/- 4.3 degrees to 5.7 +/- 4.8 degrees and 17.4 +/- 6.4 degrees to 6.9 +/- 7.7 degrees at epicardium and endocardium. CONCLUSIONS Untwisting occurs principally during isovolumic relaxation before filling and is markedly enhanced in speed and magnitude by catecholamines. This partial return of the left ventricle to its preejection configuration before mitral valve opening could represent an important mechanism for the release of potential energy stored in elastic elements during the systolic deformation. These myocardial restoring forces would be markedly enhanced by physiological changes consequent to catecholamines such as during exercise, offsetting the concomitant shortening of the filling period.

356 citations


Cited by
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Journal ArticleDOI
TL;DR: Authors/Task Force Members: John J. McMurray (Chairperson) (UK), Stamatis Adamopoulos (Greece), Stefan D. Anker (Germany), Angelo Auricchio (Switzerland), Michael Böhm ( Germany), Kenneth Dickstein (Norway), Volkmar Falk (Sw Switzerland), Gerasimos Filippatos (G Greece), Cândida Fonseca (Portugal), Miguel Angel Gomez-Sanchez (Spain).
Abstract: Authors/Task Force Members: John J.V. McMurray (Chairperson) (UK)*, Stamatis Adamopoulos (Greece), Stefan D. Anker (Germany), Angelo Auricchio (Switzerland), Michael Böhm (Germany), Kenneth Dickstein (Norway), Volkmar Falk (Switzerland), Gerasimos Filippatos (Greece), Cândida Fonseca (Portugal), Miguel Angel Gomez-Sanchez (Spain), Tiny Jaarsma (Sweden), Lars Køber (Denmark), Gregory Y.H. Lip (UK), Aldo Pietro Maggioni (Italy), Alexander Parkhomenko (Ukraine), Burkert M. Pieske (Austria), Bogdan A. Popescu (Romania), Per K. Rønnevik (Norway), Frans H. Rutten (The Netherlands), Juerg Schwitter (Switzerland), Petar Seferovic (Serbia), Janina Stepinska (Poland), Pedro T. Trindade (Switzerland), Adriaan A. Voors (The Netherlands), Faiez Zannad (France), Andreas Zeiher (Germany).

6,367 citations

Journal ArticleDOI
TL;DR: ESC guidelines for the diagnosis and treatment of acute and chronic heart failure have been developed in collaboration with the Heart Failure Association (HFA) of the ESC 2012 Task Force for the Diagnosis and Treatment of Acute and Chronic Heart Failure 2012 as mentioned in this paper.
Abstract: ESC guidelines for the diagnosis and treatment of acute and chronic heart failure 2012 : The Task Force for the Diagnosis and Treatment of Acute and Chronic Heart Failure 2012 of the European Society of Cardiology. Developed in collaboration with the Heart Failure Association (HFA) of the ESC

5,841 citations

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TL;DR: This document summarizes current capabilities, research and operational priorities, and plans for further studies that were established at the 2015 USGS workshop on quantitative hazard assessments of earthquake-triggered landsliding and liquefaction.
Abstract: ![Figure][1] ![Figure][1] ![Figure][1] ![Figure][1] ![Figure][1] ![Figure][1] ![Figure][1] ![Figure][1] ![Figure][1] ![Figure][1] ![Figure][1] ![Figure][1] ![Figure][1

4,975 citations

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TL;DR: This paper summarizes the proceedings of several meetings of the European Network for Non-invasive Investigation of Large Arteries and is aimed at providing an updated and practical overview of the most relevant methodological aspects and clinical applications in this area.
Abstract: In recent years, great emphasis has been placed on the role of arterial stiffness in the development of cardiovascular diseases. Indeed, the assessment of arterial stiffness is increasingly used in the clinical assessment of patients. Although several papers have previously addressed the methodological issues concerning the various indices of arterial stiffness currently available, and their clinical applications, clinicians and researchers still report difficulties in selecting the most appropriate methodology for their specific use. This paper summarizes the proceedings of several meetings of the European Network for Non-invasive Investigation of Large Arteries and is aimed at providing an updated and practical overview of the most relevant methodological aspects and clinical applications in this area.

4,901 citations