The FERMI free-electron lasers.

FERMI is a seeded free-electron laser (FEL) facility located at the Elettra laboratory in Trieste, Italy, and is now in user operation with its first FEL line, FEL-1, covering the wavelength range between 100 and 20 nm. The second FEL line, FEL-2, a high-gain harmonic generation double-stage cascade covering the wavelength range 20-4 nm, has also completed commissioning and the first user call has been recently opened. An overview of the typical operating modes of the facility is presented.

Evaluation of right ventricular function performed by 3D-echocardiography in scleroderma patients.

The impairment of the right ventricle (RV) in systemic sclerosis (SSc) is usually related to pulmonary arterial hypertension (PAH). New echocardiographic techniques, such as 3-dimensional echocardiography (3DE) and 2-dimensional speckle tracking (2DSTE), allow an accurate evaluation of the RV function. The aim of this study was to evaluate the RV function using 3DE and 2DSTE in SSc patients with no history of heart disease and no PAH. Forty-five SSc patients, 42 females and 3 males, 28 with limited cutaneous SSc (lcSSc) and 17 with diffuse cutaneous SSc (dcSSc), were studied. Forty-three age- and gender-matched healthy subjects were enrolled as controls. All of them underwent a 3DE and 2DSTE ecocardiographic evaluation of the RV function. Systolic pulmonary arterial pressure (sPAP) and total pulmonary vascular resistance (tPVR) were also estimated by power doppler. RV echocardiographic parameters were compared in the different subsets of SSc patients. A statistical analysis was performed by t-test, ANOVA and multiple logistic regression. RV areas in 2DSTE and volumes in 3DE were higher and RV function parameters were reduced in SSc patients compared with controls. Also sPAP and tVPR were higher, but they did not reach pathological values. Echocardiographic alterations were more pronounced in patients with lcSSc. 3DE and 2DSTE echocardiography allowed us to detect morphological and functional alterations of the RV in a group of SSc patients with no clinical signs of heart disease and no PAH. These patients had significantly higher sPAP and tPVR than healthy controls without reporting values compatible with PAH. These data suggest that RV alterations are related to a pressure overload rather than to an intrinsic myocardial involvement in SSc.

One-and-a-half ventricle repair as a surgical alternative to Fontan revision in an adult.

We report a case of a young man with hypoplastic right ventricle, who presented with recurrent untreatable arrhythmias after a Bjork Fontan procedure in infancy. He underwent one-and-a-half ventricle repair as an alternative surgery to Fontan revision.

Recommendations for transoesophageal echocardiography: update 2010.

Transoesophageal echocardiography (TOE) is a standard and indispensable technique in clinical practice. The present recommendations represent an update and extension of the recommendations published in 2001 by the Working Group on Echocardiography of the European Society of Cardiology. New developments covered include technical advances such as 3D transoesophageal echo as well as developing applications such as transoesophageal echo in aortic valve repair and in valvular interventions, as well as a full section on perioperative TOE.

Characterisation of microbunching instability with 2D Fourier analysis.

The optimal performance of high-brightness free-electron lasers (FELs) is limited by the microbunching instability, which can cause variations in both the slice energy spread and longitudinal profile of electron beams. In this paper, we perform 2D Fourier analysis of the full bunch longitudinal phase space, such that modulations in both planes can be studied simultaneously. Unlike the standard 1D analysis, this method is able to reveal modulations in a folded phase space, which would otherwise remain uncovered. Additionally, the plasma oscillation between energy and density modulations is also revealed by this method. The damping of the microbunching instability, through the use of a laser heater, is also analysed with this technique. We confirm a mitigation of the amplitude of modulation and a red-shift of the microbunching frequency as the energy spread added increases. As an outcome of this work, a systematic experimental comparison of the development of the instability in the presence of different compression schemes is here presented for the first time.

An atypical case of pulmonary embolism from a jugular vein.

Neck venous malformations and their potentially life-threatening complications are rarely reported in the available literature. Cases of aneurysmal or hypo-plastic jugular vein thrombosis associated with systemic embolization have not been frequently reported. We present the case of a 60-year-old male, without any known risk factors for thromboembolic disease, admitted for sudden onset dyspnea. The physical examination was remarkable for a right lateral cervical mass, expanding with Valsalva maneuver. Thoracic CT with contrast established the diagnosis of bilateral pulmonary embolism and raised the suspicion of superior vena cava and right atrial thrombosis. Bedside transthoracic echocardiography confirmed the presence of a large right atrial thrombus, with intermittent protrusion through the tricuspid valve. Systemic thrombolysis with Alteplase was initiated shortly after diagnosis, in parallel with unfractionated heparin, with complete resolution of the intracavitary thrombus documented by echocardiography. The patient showed significant improvement in symptoms and was later started on oral anticoagulation. Computed vascular tomography of the neck was performed before discharge, showing hypoplasia of the left internal jugular vein and aneurismal dilation of the contralateral internal jugular vein, without thrombosis. There were no identifiable systemic causes for thrombosis. Surgical resection of the aneurismal jugular vein was excluded, because of its potential to cause intracranial hypertension. The preferred therapeutic option in this case was long-term oral anticoagulation. Learning points: Internal jugular venous malformations, such as aneurisms or hypoplasia, could be associated with an increased risk of thrombosis and major embolic events. Systemic thrombolysis can be an efficient solution in cases of pulmonary embolism with right heart thrombosis. Multimodality imaging is greatly valuable in clarifying the diagnosis of atypical cases.

Coherent THz Emission Enhanced by Coherent Synchrotron Radiation Wakefield.

We demonstrate that emission of coherent transition radiation by a ∼1 GeV energy-electron beam passing through an Al foil is enhanced in intensity and extended in frequency spectral range, by the energy correlation established along the beam by coherent synchrotron radiation wakefield, in the presence of a proper electron optics in the beam delivery system. Analytical and numerical models, based on experimental electron beam parameters collected at the FERMI free electron laser (FEL), predict transition radiation with two intensity peaks at ∼0.3 THz and ∼1.5 THz, and extending up to 8.5 THz with intensity above 20 dB w.r.t. the main peak. Up to 80-µJ pulse energy integrated over the full bandwidth is expected at the source, and in agreement with experimental pulse energy measurements. By virtue of its implementation in an FEL beam dump line, this work promises dissemination of user-oriented multi-THz beamlines parasitic and self-synchronized to EUV and x-ray FELs.

Electrocardiographic evolutionary changes and left ventricular remodeling after acute myocardial infarction: results of the GISSI-3 Echo substudy.

OBJECTIVES: The aim of this study was to describe the electrocardiographic (ECG) evolutionary changes after an acute myocardial infarction (AMI) and to evaluate their correlation with left ventricular function and remodeling. BACKGROUND: The QRS complex changes after AMI have been correlated with infarct size and left ventricular function. By contrast, the significance of T wave changes is controversial. METHODS: We studied 536 patients enrolled in the GISSI-3-Echo substudy who underwent ECG and echocardiographic studies at 24 to 48 h (S1), at hospital discharge (S2), at six weeks (S3) and six months (S4) after AMI. RESULTS: The number of Qwaves (nQ) and QRS quantitative score (QRSs) did not change over time. From S2 to S4, the number of negative T waves (nT NEG) decreased (p < 0.0001), wall motion abnormalities (%WMA) improved (p < 0.001), ventricular volumes increased (p < 0.0001) while ejection fraction remained stable. According to the T wave changes after hospital discharge, patients were divided into four groups: stable positive T waves (group 1, n = 35), patients who showed a decrease > or =1 in nT NEG (group 2, n = 361), patients with no change in nT NEG (group 3, n = 64) and those with an increase > or =1 in nT NEG (group 4, n = 76). The QRSs and nQ remained stable in all groups. Groups 3 and 4 showed less recovery in %WMA, more pronounced ventricular enlargement and progressive decline in ejection fraction than groups 1 and 2 (interaction time x groups p < 0.0001). CONCLUSIONS: The analysis of serial ECG can predict postinfarct left ventricular remodeling. Normalization of negative T waves during the follow-up appears more strictly related to recovery of regional dysfunction than QRS changes. Lack of resolution and late appearance of new negative T predict unfavorable remodeling with progressive deterioration of ventricular function.

Relation of right ventricular morphology and function in pectus excavatum to the severity of the chest wall deformity.

Although pectus excavatum (PE) is thought to impair right ventricular (RV) performance, the degree of RV dysfunction, if any, produced by this chest wall deformity remains controversial. To address this issue, we performed 2-dimensional echocardiography and chest wall radiography in 28 subjects with mild-to-severe degrees of PE to assess RV morphology and function in relation to the degree of the chest wall deformity. Measurements of RV anatomy and function obtained in these patients were compared to those of 24 normal control subjects of similar age and sex. In subjects with PE, mean RV outflow tract diameter at the aortic root level was narrower (1.4 +/- 0.3 cm/m2) and end-diastolic (10 +/- 2.3 cm2/m2) and end-systolic (5.8 +/- 1.4 cm2/m2) areas were larger than those in normal controls (1.6 +/- 0.3, 8.6 +/- 1.7, and 4.5 +/- 1.2 cm2/m2, respectively; p < 0.013). The magnitude of these abnormalities was related to the degree of the chest wall deformity evaluated on the chest radiogram (r = 0.54, 0.51, and 0.49, respectively). RV planar emptying fraction, an index of RV systolic function, was reduced in subjects with PE (42 +/- 10%) compared to the normal controls (48 +/- 10%; p = 0.047). No relation could be found, however, between this index and the severity of the chest wall deformity.(ABSTRACT TRUNCATED AT 250 WORDS)

Left ventricular myocardial function in myotonic dystrophy.

Myotonic dystrophy is an autosomal dominant disease affecting many organ systems, including the heart. Abnormalities of the cardiac conduction system are a frequent and well-documented finding in this neuromuscular disease, whereas overt signs of heart failure are rarely reported. However, controversy exists about the prevalence of preclinical left ventricular (LV) dysfunction in patients with myotonic dystrophy who have no symptoms of heart failure. To address this issue, load-independent LV function indexes were compared in patients with myotonic dystrophy and in normal subjects. LV measurements were obtained with M-mode echocardiography in 43 consecutive patients with myotonic dystrophy (mean age 35 +/- 14 years) who had no clinical evidence of heart failure, and in 35 sex- and age-matched controls. A cuff sphygmomanometer was used to determine blood pressure. No difference was found between patients and control subjects in the percentage of LV ejection fraction predicted for end-systolic stress (103 +/- 7 vs 103 +/- 7%; p = 0.97) or in the end-systolic stress/volume index ratio (2.9 +/- 0.5 vs 2.7 +/- 0.4 dyne7/cm3; p = 0.09). Similarly, no significant difference in LV myocardial function was detected between the 19 patients with a mild degree of the neuromuscular disease and in the 24 with a moderate or severe degree of the disease. Finally, LV myocardial function was compared between patients with myotonic dystrophy and atrioventricular or intraventricular conduction disturbances (n = 8) and those without these disturbances (n = 35), but no significant difference in the percentage of LV ejection fraction predicted for end-systolic stress or in the end-systolic stress/volume index ratio could be detected.(ABSTRACT TRUNCATED AT 250 WORDS)

Changes in effective aortic valve area during ejection in adults with aortic stenosis.

Measurements of valve orifice area in aortic stenosis are based on the assumption that orifice area remains constant throughout ejection and is independent of transvalvular gradients and flow. Recent studies, however, have suggested that the calculated valve area of calcific aortic stenosis may change in different flow conditions. Therefore, we tested the hypothesis that in vivo effective orifice area of a stenotic aortic valve changes continuously during ejection, which would make a single area measurement a potentially inadequate indicator of the severity of the stenosis. Doppler measurements of flow velocity in the ascending aorta and in the left ventricular outflow tract at peak velocity, at half-peak velocity during acceleration (midacceleration), and at half-peak velocity during deceleration (mid-deceleration) were obtained in 26 patients with aortic stenosis (mean gradient 50 +/- 19 mm Hg and effective aortic orifice are 0.7 +/- 0.3 dcm2) and in 14 normal subjects of similar age and gender, to calculate instantaneous effective aortic orifice area at midacceleration, at peak velocity and at mid-deceleration. In the 26 patients with aortic stenosis, aortic valve area at midacceleration was 84 +/- 15% of valve area at peak velocity (p < 0.0001), and valve area at mid-deceleration was 113 +/- 17% of that measured at peak velocity (p < 0.01). Conversely, in normal subjects, aortic valve area remained constant during ejection and was 97 +/- 5% and 99 +/- 6% of valve area at peak velocity, respectively, at midacceleration and mid-deceleration (p > 0.05). In addition, in patients with aortic stenosis the percentage of change in effective aortic valve area from midacceleration to mid-deceleration varied widely, from -17% to +49% (mean change +26 +/- 14%). There was no relation between percentage of change in effective valve area and mean transaortic gradient (r = 0.05; p = 0.30) or effective valve area at peak velocity (r = -0.11; p = 0.14). Our results indicate that effective aortic valve area continues to change during ejection in patients with aortic stenosis, and that the magnitude of this change is independent of the usual indexes of severity of the stenosis. Conversely, effective aortic valve area remains constant during ejection in normal subjects.

Reproducibility of wall motion score and its correlation with left ventricular ejection fraction in patients with acute myocardial infarction.

The inter- and intraobserver variability, as well as the relation to left ventricular (LV) function indexes, of LV wall motion score calculated using the 16- and 11-segment models of LV segmentation were assessed in 105 patients with acute myocardial infarction who were examined at 36 +/- 7 hours from onset of symptoms. In these patients, the use of the 16-segment model of LV segmentation portends to a significantly higher inter- and intraobserver reproducibility of segmental wall motion score than the use of the 11-segment model. In addition, wall motion score assessed with the more detailed 16-segment model of LV segmentation showed a significantly higher correlation with LV ejection fraction than the wall motion score assessed using the 11-segment model.

Use of a common computerized program for echocardiogram archiving and reporting over a regional territory: feasibility and clinical and research impact during a 5-year experience.

The aims of this study were to optimize interlaboratory standardization of echocardiographic reporting (qualitative terms and quantitative parameters) and to evaluate the feasibility and clinical and research impact of collecting echocardiographic data in a standard computerized format over a geographical territory. In April 1992, a computer program of echocardiogram archiving and reporting (ARCE) was distributed at no cost to the 23 hospital echocardiographic laboratories operating in our region (Liguria). In April 1993 (1-year survey), 16 (70%) of the 23 hospital echo laboratories operating in our region were routinely using ARCE. In April 1997 (4-year survey ), 21 (87%) of the 24 echo laboratories were routinely using the system and 128,642 echocardiograms had been databased. ARCE is a powerful tool both for education and training in cardiac ultrasound and for undertaking multicenter studies by 95% of the users. Regarding the quality improvement process, we achieved 3 main goals: (1) a unique report format from 87% of Ligurian echo laboratories, which improved the communication between echocardiographers and other physicians; (2) development of specific, Ligurian population-based reference limits for M-mode and 2-dimensional quantitative parameters; and (3) interlaboratory comparison and standardization of both quantitative and semiquantitative evaluation of heart valve disease, left ventricular systolic and diastolic function, valve prosthesis function, and left ventricular hypertrophy. Regarding the scientific activity in Liguria, 9 multicenter studies in which 15 Ligurian echo laboratories took part were organized and completed in 5 years. Our 5-year experience shows that it is possible to create a large database of echocardiographic data that uses a fast, easy-access, and easy-to-use program of echo archiving and reporting that contains standardized variables. The use of this program on a regional territory scale appeared feasible and useful both for educational and training purposes. In addition, it stimulated the quality improvement process in echocardiography as well as performance of epidemiologic and clinical multicenter studies.

A large left ventricular thrombus evolving towards canalization and mimicking a left ventricular pseudoaneurysm: an echocardiographic study.

We describe a case of a large apical left ventricular thrombus evolving towards canalization and showing echocardiographic features mimicking a left ventricular pseudoaneurysm. Only serial echocardiographic studies allowed an appreciation of the changing morphologic features of the apical structure, permitting differential diagnosis between a canalization of an evolving thrombus and a myocardial free-wall rupture with pseudoaneurysm formation.

Normal echocardiographic characteristics of the Sorin Bicarbon bileaflet prosthetic heart valve in the mitral and aortic positions.

Doppler echocardiographic characteristics of normally functioning Sorin Bicarbon prostheses were prospectively assessed in 226 consecutive patients (135 male and 91 female patients, mean age 61 +/- 10 years) with 233 valves in the mitral (n = 67) and aortic (n = 166) positions whose function was considered normal by clinical and echocardiographic evaluation. Patterns of "normal" transprosthetic leakage were assessed with transthoracic echocardiography in all valves and with transesophageal echocardiography in six selected mitral valve prostheses. For the mitral valve prostheses, we found that peak and mean gradient, as well as pressure half-time, were not significantly different in either the 25 or the 31 mm valves (median values from 15 to 10 mm Hg, from 4 to 4 mm Hg, and from 70 to 83 ms; p = Not significant for all). On transthoracic study, 12 patients (17%) with a Sorin Bicarbon valve in the mitral position showed minimal transprosthetic leakage. On transesophageal study, all patients showed a transprosthetic leakage whose spatial distribution had a complex pattern: in planes orthogonal to the leaflet axis, two to four jets arising from the hinge points and converging toward the center of the valve plane could be visualized; in planes parallel to the leaflet axis, there were three jets, the two lateral ones diverging and the central one perpendicular to the valve plane. For the aortic valve prostheses, there was a significant decrease in transprosthetic gradients and an increase in effective orifice areas as prosthesis size increased. Peak and mean gradients decreased from a median value of 25 and 13 mm Hg in the 19 mm valves to 9 and 5 mm Hg in the 29 mm valves, respectively. Effective prosthetic valve area calculated with the continuity equation increased from a median value of 0.97 cm2 for the 19 mm size valves to 3.45 cm2 for the 29 mm size. With analysis of variance, effective prosthetic aortic valve area differentiated various valve sizes (F = 40.9, p < 0.0001) better than peak (F = 10.3, p < 0.0001) or mean (F = 8.04, p < 0.0001) gradients alone did. Furthermore, effective prosthetic aortic valve area correlated better than peak and mean gradients with prosthetic size (r = 0.76, r = -0.45, and r = -0.39, respectively). On transthoracic study, 109 patients (66%) showed minimal transprosthetic leakage. These normal values, obtained in a large number of patients with normofunctioning mitral and aortic Sorin Bicarbon valves, may help to identify Sorin Bicarbon prosthesis dysfunction.

[Doppler echocardiographic evaluation of functional parameters of mechanical and biological valve prostheses]. / Valutazione tramite ecocardiografia-Doppler dei parametri funzionali di protesi valvolari meccaniche e biologiche.

We studied and compared functional parameters in 314 valvular prostheses. The following parameters have been calculated: mean transvalvular gradients for aortic and mitral prostheses and functional area by Pht (pressure half time) for mitral prostheses. All patients with important depression in myocardial function, tachycardia or malfunctioning prostheses were excluded. 173 prostheses were in aortic position and 141 in mitral position. Mitral prostheses were: 31 biological and 110 mechanical. We subdivided mechanical prostheses in monoleaflet (Omnicarbon, Sorin-Carbocast and Allcarbon, Medtronic, Bjork-Shiley) and bileaflet (Sorin-Bicarbon, St. Jude). These three groups were compared: mean transvalvular gradients and area showed no differences. Aortic prostheses were: 33 biological and 140 mechanical; mechanical prostheses were subdivided in two groups: monoleaflet (Sorin Allcarbon e Carbocast, Bjork-Shiley, Medtronic, Omnicarbon) and bileaflet (Sorin-Bicarbon, St. Jude). Mean transvalvular gradients of these three groups were compared within each group for every size: bileaflet prostheses demonstrated inferior gradients than biological and monoleaflet for 19-21 and 23 sizes; in superior sizes there were no significant differences. Further analysis showed a significant correlation among gradients and body surface area in the 21 size prostheses (p = 0.004). Bileaflet prostheses in this subgroup showed less increase in mean gradient with surface area than mechanical and biological ones.

Dynamic left ventricular outflow tract obstruction: an unusual mechanism mimicking anterior myocardial infarction with cardiogenic shock.

Cardiogenic shock is a frequent and threatening complication in the course of acute myocardial infarction. Besides the well known causes (left ventricular failure, acquired interventricular defect, papillary muscle rupture, free wall rupture) other less frequent mechanisms recognize a functional substrate. The recognition of such mechanisms makes us to revert to the treatments with completely different prognostic implications. In our Coronary Care Unit we encountered, in a period of 12 months, 4 patients who presented clinical, electrocardiographic and/or echographic signs and symptoms of acute myocardial infarction, with different degrees of heart failure up to cardiogenic shock. Only 1 patient showed a severe stenosis of the left anterior descending coronary artery and a significant creatine kinase reduction. Left ventriculography, performed at admission, was unable to disclose the true mechanism of clinical presentation. Only a thorough echographic examination disclosed the presence of a dynamic left ventricular outflow tract obstruction as the cause of heart failure culminating in cardiogenic shock. Once recognized, pathophysiological treatment (administration of beta-blockers and withdrawal of vasodilators, inotropic drugs and intra-aortic balloon pump) led to a dramatic improvement, with an almost complete left ventricular function recovery. Left ventricular outflow tract obstruction is a mechanism that can lead to severe heart failure as a complication of an acute myocardial infarction. Conversely such a mechanism can be precipitated by other causes (hypotension, hypovolemia, especially in hypertensive patients) and can mimic an acute myocardial infarction. Its incidence is not negligible: in our Coronary Care Unit it accounted for about 15% of all cases of myocardial infarction requiring inotropic support. An accurate echocardiographic examination is mandatory even after coronary angiography, and always permits the physician to select the appropriate therapy.

Feasibility and clinical value of "intelligent" compression and digital storage of transthoracic echocardiograms in day-to-day practice.

BACKGROUND: The aim of this study was to assess the clinical concordance of expert cardiologists' interpretation of echocardiographic studies recorded on Super-VHS videotape or stored in magneto-optical disk, as well as the feasibility and clinical value of intelligent compression and digital storage of echocardiographic data as cine-loops and still-frames for interpretation of transthoracic echocardiographic images in clinical practice. METHODS: All clinical cardiologists experienced in echocardiography in our department (n = 10) reported on a standardized worksheet checklist the echocardiographic data of 7 consecutive patients (140 reports), and recorded them on videotape or magneto-optical disks to compare the interpretation of videotaped studies, acquired in the usual way, with clinically compressed studies stored to magneto-optical disks using a standard (Italian Society of Echocardiography) image acquisition protocol. RESULTS: The time interval between analog and digital study readings was 50 +/- 15 days. Except for tricuspid valve regurgitation grading (k = 0.28) and for left ventricular global hypokinesia (k = 0.32), the intraobserver agreement in the interpretation of the 3290 cardiovascular morphological and functional findings found on analog and digitally stored images was good (k value ranging from 0.66 to 1.00). The wall motion score index was 1.56 +/- 0.53 when interpreting analog studies, and 1.52 +/- 0.54 on digital studies (p = 0.35). Conversely, the interobserver variability of the wall motion score index (Gini index ranging from 0 to 0.80) was significantly lower when interpreting studies stored digitally than when analog ones were examined (0.48 +/- 0.021 and 0.52 +/- 0.023 respectively, p = 0.006). In comparison to videotape recordings, digital storage of echocardiographic studies significantly shortened the time to image access for study review (327 +/- 62 and 30 +/- 4 s, respectively, p < 0.0001) and the reading time (600 +/- 300 and 540 +/- 300 s respectively, p = 0.034), rendered study accessibility easier (difficult or good: 73 vs 43% of observers, fast or optimal: 27 vs 57% of observers respectively, p = 0.0011) and improved the recorded image quality perception (poor: 25 vs 10% of observers, sufficient or good: 75 vs 90% of observers respectively, p = 0.022), without loss of study completeness (insufficient: 18 vs 17% of observers, adequate or complete: 82 vs 83% of observers, respectively; p = NS). Finally, from September 1, 1999, digital storage has become routine practice for patients admitted to our Department. By December 31, 1999, 411 echo studies had been stored: 7 +/- 3 cine-loop/study, 32 +/- 18 frames/cine-loop, and 3 +/- 2 still-frames/study. The average amount of memory needed for storage was 18.6 +/- 11.9 MB/study. CONCLUSIONS: Clinical compression of echocardiographic studies seems to be an accurate summary of the complete examination recorded to videotape for the assessment of patients admitted in the coronary care unit. In addition, digitally stored studies allow a significant improvement in the interobserver reproducibility of wall motion score assessment.

[Digital revolution in the echocardiography laboratory. Current status and future perspectives] . / La rivoluzione digitale nel laboratorio di ecocardiografia. Stato attuale e prospettive future.

Echocardiography is changing from an operative modality in which most images are stored in analog fashion on videotape into one with most data stored digitally. This transition is accelerating today, fueled by several factors. First, there is widespread recognition of the value of digital storage of echocardiograms, including random access to studies as well as to images within a study, side-by-side comparison with prior studies, easier quantification, and multiplication and remote transmission of images without degradation. Second, continuous improvement of the cost/performance ratio of modern computers makes routine digital echocardiography both feasible and affordable. Finally, the formulation and acceptance within the industry of the DICOM image formatting standard for echocardiography. The acceptance of this standard allows the echo-labs around the world to be free to choose individual echo-machines on the basis of their individual merits for their laboratories with the assurance that these machines will be able to communicate with each other by an internationally agreed upon standard. Advantages of digital echocardiography are overwhelming and there is little doubt that this approach will be essential for the proper utilization of this technique. The technology will undoubtedly continue to change. Those who are waiting for it to be perfected may be waiting for a long time.

[Is a more efficient operative strategy feasible for the emergency management of the patient with acute chest pain?]. / E realizzabile una strategia operativa più efficace per la gestione in urgenza del paziente con dolore toracico acuto?

Patients with acute chest pain are a common problem and a difficult challenge for clinicians. In the United States more than 5 million patients are examined in the emergency department on a yearly basis, at a cost of 6 billion dollars. In the CHEPER registry the prevalence of patients with chest pain in the Emergency Department was 5.3%. Similarly, in 1997 at our institution the prevalence was 4.8%. Only 50% of the patients are subsequently found to have cardiac ischemia as the cause of their symptoms and 50-60% of them showed a non-diagnostic electrocardiogram (ECG). Twenty-five-50% of chest pain patients are not appropriately admitted to the hospital and despite this conservative approach, acute myocardial infarction is misdiagnosed up to 8% of patients with acute chest pain who are released from the emergency department without further evaluation, accounting for approximately 20% of emergency department malpractice in the United States. Important diagnostic information is covered by the patient's medical history, physical examination, and ECG, but often this approach is inadequate for a definitive diagnosis. Creatine kinase (CK) and CK isoenzyme--cardiac muscle subunit (CK-MB)--are traditionally obtained in the emergency department in patients admitted for suspected acute coronary syndrome. Mass measurements of CK-MB have improved sensitivity and specificity, and to date this is the gold standard test for diagnosis of acute myocardial infarction. CK-MB, however, is not a perfect marker because it is not totally cardiac specific and does not identify patients with unstable angina and minimal myocardial damage. There are no controlled clinical impact trials showing that these tests are effective in deciding whether to discharge or to appropriately admit the patient with suspected acute coronary syndrome. Relevant investigative interest has recently been focused on new markers for myocardial injury, including myoglobin, cardiac troponins T and I. Myoglobin, a sensitive but not specific marker for cardiac damage, increases earlier than CK-MB and cardiac troponins. It should be used early after symptom onset and in conjunction with a more specific marker of myocardial damage. Cardiac troponins T and I are highly specific markers for cardiac damage, rise parallel to CK-MB and remain elevated longer, up to 5 to 9 days. They are useful for detection of less severe degrees of myocardial injury, which may occur in several patients with unstable angina who are at higher risk of cardiac events. Recent studies suggest that cardiac troponins have good diagnostic performance and prognostic value in the heterogeneous population of patients seen in the Emergency Department with acute chest pain. Despite these promising data, several analytical and interpretative problems in the routine use of cardiac troponins must be solved. Incremental value of echocardiography in acute chest pain patients is still uncertain. Echocardiography can be recommended as an adjunctive test if readily available during acute chest pain or prolonged pain, especially in patients without previous myocardial infarction. Rest myocardial radionuclide imaging has been studied in the emergency department setting and although the overall diagnostic performance and prognostic value of sestamibi has been found to be promising, it is not suitable, in our country, for extensive clinical use. ECG exercise stress test in the emergency department population has been shown to be safe and it has a good negative predictive value for cardiac events. It should be recommended that any institution identify specific and shared protocol and strategies for management of patients with chest pain. These should include basal clinical evaluation, serial ECG and the use of specific and sensitive myocardial markers. Adjunctive tests, such as echocardiography, nuclear studies and stress tests should be employed when indicated taking into account local facilities.