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BackgroundIn contrast with the setting of acute myocardial infarction, there are limited data regarding the impact of diabetes mellitus on clinical outcomes in contemporary cohorts of patients with chronic coronary syndromes. We aimed to investigate the prevalence and prognostic impact of diabetes according to geographical regions and ethnicity.Methods and resultsCLARIFY is an observational registry of patients with chronic coronary syndromes, enrolled across 45 countries in Europe, Asia, America, Middle East, Australia, and Africa in 2009–2010, and followed up yearly for 5 years. Chronic coronary syndromes were defined by ≥1 of the following criteria: prior myocardial infarction, evidence of coronary stenosis >50%, proven symptomatic myocardial ischaemia, or prior revascularization procedure.Among 32 694 patients, 9502 (29%) had diabetes, with a regional prevalence ranging from below 20% in Northern Europe to ∼60% in the Gulf countries. In a multivariable-adjusted Cox proportional hazards model, diabetes was associated with increased risks for the primary outcome (cardiovascular death, myocardial infarction, or stroke) with an adjusted hazard ratio of 1.28 (95% confidence interval 1.18, 1.39) and for all secondary outcomes (all-cause and cardiovascular mortality, myocardial infarction, stroke, heart failure, and coronary revascularization). Differences on outcomes according to geography and ethnicity were modest.ConclusionIn patients with chronic coronary syndromes, diabetes is independently associated with mortality and cardiovascular events, including heart failure, which is not accounted by demographics, prior medical history, left ventricular ejection fraction, or use of secondary prevention medication. This is observed across multiple geographic regions and ethnicities, despite marked disparities in the prevalence of diabetes.ClinicalTrials identifierISRCTN43070564

SUMMARYMethicillin-resistantStaphylococcus aureus(MRSA) commonly causes infection in hospitalized patients. Resistance is due to the acquisition ofmecA gene located on the chromosomal element SCCmecand to date 12 types have been identified. Specific epidemic clones of MRSA have emerged with enhanced ability to spread within and among hospitals and to cross national boundaries. We studied 30 isolates from patients with MRSA infections at two hospitals in Porto Alegre city from April to December, 2008 and determined their SCCmectype by PCR. Representative strains were typed by PFGE. Eighteen (60%) isolates carried SCCmectype III and had PFGE profiles clonally related to the previously characterized Brazilian epidemic clone, and 11 (36·7%) isolates with pulsotypes closely related to the Cordobes/Chilean clone harboured SCCmectype I. To the best of our knowledge, this is the first report of the appearance of Cordobes/Chilean clone involved in nosocomial infection in Brazil.

IEEE Standard for Local and Metropolitan Area Networks (hereafter IEEE 802.16; online at http://standards.ieee.org/getieee802/802.16.html) is one of the most promising mobile and fixed broadband wireless access technologies for next-generation all-IP networks in the 3.5 GHz band (European spectrum profile). Commonly known as Universal WiMAX (worldwide inter-operability for microwave access), this access technology reaches a high bit rate and covers large areas with a single base station, making it possible to offer connectivity to end users in a cost-effective way. A further useful property of the WiMAX technology is that the transmission can be used both in line-of-sight (LOS) and non-line-of-sight (NLOS) environments, allowing highly feasible communications (WiMAX Forum 2004). Thanks to these features, IEEE 802.16 opens the way to the use of wireless technologies in the environmental monitoring of areas such as seismic and volcanic zones. Volcanic eruptions, in particular, are among the highest natural risks in the world. About 600 volcanoes have erupted in historical times, and many are located near densely populated areas. An adequate monitoring system is essential to understanding the physical processes preceding an eruption and for mitigating the risk of such an event. Active volcano surveillance is primarily based on the analysis of geophysical and geochemical parameters gathered by monitoring networks. Seismological methods are among the most useful methods for monitoring volcanoes. In fact, several types of seismic signals, e.g. , volcano-tectonic earthquakes (VT), long-period events (LP), and volcanic tremors, can occur before and during an eruption (McNutt 2005). The analysis and interpretation of these seismic signals is a very important task for volcanic eruption forecasting. WiMAX technology can be applied to provide broadband wireless access in volcano monitoring scenarios to solve some of the problems that prevent us from improving surveillance of volcanic activities during emergencies. In particular, this paper focuses on a novel …

Wir berichten uber einen 85-jahrigen Patienten, bei dem aufgrund einer Leistungsminderung (NYHA III) eine kardiologische Diagnostik erfolgte und mittels Echokardiographie und Cardio-CT ein Herztumor als Ursache diagnostiziert wurde. Die endgultige Diagnose eines Burkitt-Lymphoms konnte jedoch erst durch eine Biopsie gestellt werden. Aufgrund des fortgeschrittenen Alters des Patienten wurde auf die angestrebte chirurgische Therapie verzichtet und der Patient mit 6Zyklen einer potentiell kurativen Chemotherapie (CHOP-Schema) behandelt. Diese Therapie hat der Patient gut toleriert. Mittels Cardio-CT konnte eine komplette Remission des Tumors nachgewiesen werden, der Patient befindet sich 6Monate nach Chemotherapie im NYHA-StadiumI.

An 85-year-old patient suffered from progressive deterioration (NYHA III) for several months. Cardiac disease was suspected. Echocardiography as well as a CT scan of the heart revealed a heart tumor to be the cause. Tumor staging was negative. After transvenous biopsy, the diagnosis of a Burkitt lymphoma could be established. Due to the advanced age of the patient, the intented surgical therapy was turned down and the patient was treated with 6 courses of a potentially therapeutic chemotherapy (CHOP scheme), which was well tolerated by the patient. The following CT scan showed a complete remission of the tumor. Six months after chemotherapy the patient is in NYHA stage I.

WEBER, M., et al.: Antitachycardia Pacing for Rapid VT During ICD Charging: A Method to Prevent ICD Shocks. In patients with ICDs, rapid VTs are usually treated with shocks. It is unknown, if antitachycardia pacing (ATP) delivered once for rapid VT during capacitor charging can avoid painful shocks without increasing the risk of syncope. In patients in whom rapid monomorphic VT (cycle length 300–220 ms) could be reproducibly induced during predischarge ICD testing, the success of cardioversion (defibrillation threshold plus 10 J) and a single ATP attempt (burst with 8 or 16 stimuli) was compared using a randomized crossover study design. Consciousness of the patients was checked by the signal from a button constantly pushed by the patient. In 20 patients (ejection fraction 0.50 ± 0.19) rapid VTs (253 ± 26 ms) were reproducibly induced. A single burst successfully terminated 11 (55%) of 20 rapid VTs, 6 episodes could not be terminated with a single burst pacing and 3 VTs accelerated. Rapid VTs not terminated by ATP were significantly faster than those that could be terminated (246 vs 258 ms, P = 0.026). Cardioversion (19 ± 3 J) terminated the VTs in all cases. No patient suffered syncope during rapid VTs. A single ATP may terminate rapid VT with cycle lengths < 300 ms in 55% of patients without increasing the risk of syncope. Therefore, in rapid VTs one attempt of ATP may be suitable as an additional therapy option during ICD capacitor charging to avoid painful shocks without compromise of safety. Thus, future ICDs should implement the option of ATP during charging of capacitors.

OBJECTIVES This retrospective study was performed to provide data on ventricular tachycardias (VT) with a cycle length longer than the initially programmed tachycardia detection interval (TDI) in patients with implantable cardioverter defibrillators (ICDs). BACKGROUND It has been clinical practice to program a safety margin of 30 to 60 ms between the slowest spontaneous or inducible VT and the TDI. METHODS Baseline characteristics of 659 consecutive patients with ICDs were prospectively; follow-up information was retrospectively collected. RESULTS During a mean follow-up of 31 ± 23 months, 377 patients (57.2%) had at least one recurrent VT or ventricular fibrillation; 47 patients (7.1%) suffered 61 VTs above the TDI. The risk of a VT above the TDI ranged between 2.7% and 3.5% per year during the first four years after ICD implantation. The difference between the cycle length of the slowest VT before ICD implantation, spontaneous or induced, and the first VT above TDI was 108 ± 58 ms. Fifty-four VTs (88.5%) above the TDI were associated with significant clinical symptoms (angina or palpitation 63.9%, heart failure 6.6% and syncope 8.2%). Six patients (9.8%) had to be resuscitated. Kaplan-Meyer analysis identified New York Heart Association class II or III (p = 0.021), ejection fraction CONCLUSIONS The risk of VTs above the TDI is significantly increased in some patients, and many VTs above TDI cause significant clinical symptoms. A larger safety margin between spontaneous or inducible VTs and the TDI seems to be necessary in selected patients. This is in conflict with an increased risk of inadequate episodes and demands highly specific and sensitive detection algorithms in these patients.

Implantable cardioverter defibrillators (ICDs) are the treatment of choice in adults with symptomatic ventricular tachycardia or aborted sudden cardiac death. Treatment with implantable defibrillators is also possible in children, although experience in this patient group is scanty. A review of the literature on the subject of defibrillator therapy in combination with epicardial electrodes is provided. Endocardial electrodes, which have now become the gold standard in adult treatment, have only rarely been used in children. However, our own experience shows that endocardial electrodes can be implanted in most children, which generally obviates the need for thoracotomy.

Background and Purpose —Cardiac right-to-left shunts can be identified by transesophageal echocardiography (TEE) and by transcranial Doppler ultrasound (TCD) with the use of different contrast agents and different provocation procedures. Currently, data on an appropriate time window for the appearance of contrast bubbles in the TCD recording after the injection of the contrast medium and the comparison of different provocation maneuvers to increase right-to-left shunting are insufficient. Methods —Forty-six patients were investigated by both TEE and bilateral TCD of the middle cerebral artery. The following protocol with 6 injection modes was applied in a randomized way: (1) injection of 10 mL of agitated saline without Valsalva maneuver, (2) injection of 10 mL of agitated saline with Valsalva maneuver, (3) injection of 10 mL of a commercial galactose-based contrast agent (Echovist) without Valsalva maneuver, (4) injection of 10 mL of Echovist with Valsalva maneuver, (5) injection of 10 mL of Echovist with standardized Valsalva maneuver, and (6) injection of 10 mL of Echovist with coughing. Results —In 20 patients, a right-to-left shunt was demonstrated by TEE and contrast TCD (shunt-positive). Sixteen patients were negative in both investigations, no patient was positive on TEE and negative on TCD, and 10 patients were only positive on at least 1 TCD investigation but negative during TEE. The amount of microbubbles detected in the various tests decreased in the following order: Echovist and Valsalva maneuver, Echovist with coughing, Echovist and standardized Valsalva maneuver, saline with Valsalva maneuver, Echovist, and saline. With a time window of 20 to 25 seconds for the bubbles to appear in the TCD recording and with a sequence of first Echovist and Valsalva maneuver and then Echovist with coughing, all shunts were reliably identified with a specificity of 65% compared with TEE as the traditional gold standard. The time of first microbubble appearance was not helpful to distinguish between shunts detected on TEE and other shunts. Conclusions —TCD performed twice with 2 provocation maneuvers using Echovist is a sensitive method to identify cardiac right-to-left shunts also identified by TEE.

The aims of this study were to evaluate the clinical usefulness of magnetic resonance myelography (MR-M), to suggest technical improvements and to evaluate the results obtained by comparing them with conventional MRI and conventional myelography. A series of 14 healthy volunteers and 43 patients with myelinic or radicular disease were studied by conventional MR and MR-M on an 0.5T unit using sequences pre-optimized for the acquisition of myelographic images. MR-M did not modify the diagnosis made by conventional MRI in cases of myelinic or radicular compression, but it did provide useful additional information in 38% of cases. It provided no additional information on compressive disease. Similar results in terms of quality of information were obtained from the correlation with conventional myelography. In our opinion, MR-M is useful only for cases of discal or spondylogenetic disease.

Objectives. This retrospective study was undertaken to provide information on occurrence, risk prediction and prevention of syncope in patients with an implantable cardioverter-defibrillator (ICD).Background. ICDs effectively terminate ventricular tachycardia and fibrillation (VT/VF). Incapacitating symptoms, such as syncope, may still occur.Methods. We performed a retrospective analysis of data from 421 patients (clinical history, outpatient chart reviews and episode data) with mean (±SD) follow-up of 26 ± 18 months.Results. Of 421 patients, 229 (54.4%) had recurrent VT/VF, and 62 (14.7%) had syncope. The actuarial survival rate free of VT/VF was 58%, 45% and 37% and that for survival free of syncope was 90%, 85% and 81% at 12, 24 and 36 months after implantation, respectively. Once VT/VF had occurred, 76%, 68% and 62% of patients remained free of syncope during the following 12, 24 and 36 months, and 68%, 64% and 56% remained free of second syncope 12, 24 and 36 months after first syncope, respectively. In cases of syncope, the mean cycle length (CL) of VT was 251 ± 56 ms. A low baseline left ventricular ejection fraction (LVEF), induction of fast VT (CL 40%, fast VT had not been induced, and patients had no chronic AF; 96%, 92% and 92% of patients remained free of syncope after 12, 24 and 36 months, respectively. Once patients had a VT recurrence, syncope during the first VT and a high VT rate were the strongest risk predictors of future syncope.Conclusions. Identification of patients with an ICD with a low and high risk of syncope seems to be feasible and might help as a guide to driving restrictions in such patients.

Der Nutzen einer postoperativ routinemasig durchgefuhrten Uberprufung der Defibrillationsfunktion implantierbarer Kardioverter/Defibrillatoren (ICDs) ist unklar. Um die Indikationen zu diesen den Patienten belastenden Untersuchungen zu uberprufen, analysierten wir retrospektiv 844 ICD-Teste bei 439 Systemen und 409 Patienten. 755 ICD-Teste (89,4%) waren routinemasig (57 % vor Entlassung; 43% wahrend der Nachverfolgung) durchgefuhrt worden. Auserplanmasig erfolgten 58 ICD-Teste (6,9%) nach Aufsattigung mit einem Antiarrhythmikum und 24 ICD-Teste (2,9%) nach Austausch oder Revision einer Komponente des ICD-Systems. Sieben ICD-Teste (0,8 %) wurden durchgefuhrt, weil eine Fehlfunktion des Systems vermutet wurde. Routinemasig durchgefuhrte ICD-Teste ergaben bei sechs Patienten (0,8%) eine mangelhafte Defibrillationsfunktion. Bis auf einen Patienten fanden sich bei allen jedoch bereits vor der Testung Besonderheiten, die auf einen Fehlfunktion hatten schliesen lassen konnen. Wegen einer Anderung der Antiarrhythmika-Medikation auserplanmasig durchgefuhrte ICD-Testungen ergaben bei drei von 58 Patienten (5,2%) eine mangelhafte Defibrillationsfunktion (Amiodaron: n = 2; Flecainid: n = 1). In vier von sieben Fallen (57%), in denen eine Fehlfunktion des ICD-Systems vermutet wurde, ergab die auserplanmasige ICD-Testung eine mangelhafte Defibrillationsfunktion. Nach Revision oder Austausch einer Systemkomponente zeigte der ICD-Test stets eine effektive Defibrillation. Bei 16 ICD-Testen (1,9%) traten Komplikationen auf. Am haufigsten waren unnotige Schocks (n = 10; 1,2 %). Am schwerwiegendsten waren passagere neurologische Symptome bei vier Patienten (0,48%). Somit fuhren postoperative Uberprufungen der Defibrillationsfunktion implantierter Defibrillatoren selten zu therapierelevanten Erkenntnissen. Routinemasig erscheinen die fur den Patienten belastenden und nicht komplikationsfreien Tests verzichtbar, wenn nach einer Uberprufung der Sensing-Signale bei Sinusrhythmus, der Schrittmacherreizschwelle und der Rontgen-Thoraxbilder keine Hinweise auf eine Systemdysfunktion bestehen und intraoperativ eine Defibrillationsschwelle mit einem ausreichenden Sicherheitsabstand bestand. Nach Aufsattigung mit einem Klasse-1- oder Klasse-III-Antiarrhythmikum sollte die Defibrillationsfunktion durch einen erneuten Test sichergestellt werden.

OBJECTIVE: The aim of our study was to assess the accuracy of color Doppler imaging in diagnosing the involvement of peripancreatic vessels by pancreatic carcinoma. SUBJECTS AND METHODS: We prospectively evaluated the color Doppler images of 61 patients with pancreatic carcinoma. Our evaluations occurred before surgery and focused on vascular involvement. Absence of contact or a short contiguity (< or = 2 cm) between tumors and peripancreatic vessels was considered to be a sign of resectability on color Doppler imaging; a long contiguity (> 2 cm), compression, encasement, or thrombosis was considered to be a sign of unresectability. In all patients, the sonographic diagnosis was compared with the surgical results. RESULTS: With color Doppler imaging, we detected signs of vascular involvement in 26 of 33 patients in whom vascular involvement was found at surgery. We detected no vascular involvement in 25 of 28 patients in whom no vascular involvement was found at surgery. No false-positive diagnoses occurred when vascular encasement was revealed by color Doppler imaging. For diagnosis of vascular involvement, the sensitivity, specificity, and overall accuracy of color Doppler imaging were 79%, 89%, and 84%, respectively; positive and negative predictive values were 89% and 79%, respectively. CONCLUSION: Color Doppler imaging is a sensitive and highly specific technique in assessing vascular involvement by pancreatic cancer when absence of contact or vascular encasement is seen. When vascular encasement is detected by color Doppler imaging, a definitive diagnosis of unresectability can be made, and further diagnostic procedures can be avoided. When sonography is used in the initial evaluation of pancreatic cancer, color Doppler imaging can improve the selection of patients for further diagnostic examinations or surgical exploration.

56 patients with large CBD or intrahepatic stones underwent endoscopic and/or percutaneous treatment followed by extracorporeal shock wave lithotripsy. Percutaneous access to the biliary tract was chosen when an endoscopic approach was not possible (hepaticojejunostomy in 5 patients, 1 juxtapapillary diverticulum and I inflammatory bile duct stricture). Visualization of stones was achieved radiologically in 32 patients and by ultrasound in 24. The procedure was successful in 47 of 56 treated patients (83.9%). Clearance of the biliary tract was obtained in 25 cases (53%), whereas in 22 cases (47%) complete clearing of biliary tract was obtained only after endoscopic extraction of fragments (17 cases) or percutaneous (5 cases). The median number of shock waves in each session was 1725 (range 300–3166), which were applied during one (n=30), two (n=22) or three sessions (n=4). The only complications were 1 case of symptomatic hyperamylasemia and 3 cases of macrohematuria. In conclusion, extracorporeal lithotripsy combined with endoscopic and/or percutaneous treatment is a real alternative to surgery for difficult stones.

For most nonthoracotomy defibrillation lead systems, the transvenous anode can positioned independently of the right ventricular (RV) cathode. Usually a vertical position in the superior vena cava (SVC) is chosen. However, it is unknown if this position yields the optimal defibrillation threshold (DFT). Therefore, in 15 patients undergoing defibrillator implantation the SVC position was compared in a crossover study design with a horizontal position in the left brachiocephalic vein (BCV). Mean DFT was not different for SVC and BCV (19.2 +/- 9.6 J vs 18.5 +/- 9.1 J) but DFT of individual patients differed by up to 12 joules. A positive correlation between impedance and DFT in the BCV position (r = 0.6; P < or = 0.05) indicated that the improved geometry of the defibrillation field with the BCV position is opposed by a higher impedance found for this position (63 +/- 15 omega vs 52 +/- 7 omega). Thus, defibrillation is not improved in general although individual patients might benefit.

The authors prospectively performed serum CA 19-9 assessment, ultrasound (US), computed tomography (CT), and CT-guided fine-needle aspiration biopsy (FNAB) of the pancreas in 81 consecutive patients with suspected chronic pancreatitis or pancreatic neoplasm. The final diagnosis was pancreatic cancer in 54 patients and chronic pancreatitis in 27 patients. CA 19-9 assessment, US, CT, and FNAB were considered nondiagnostic, respectively, in 0%, 25%, 19%, and 6% of cases. When a definite diagnosis was rendered, the positive predictive value was 90% for CA 19-9 assessment, 95% for US, 98% for CT, and 100% for FNAB; the negative predictive value was, respectively, 69%, 95%, 86%, and 100%. The accuracy of all diagnostic and nondiagnostic studies was 81% for CA 19-9 assessment, 72% for US, 77% for CT, and 94% for FNAB. It is concluded that CT-guided pancreatic FNAB is the most reliable examination for enabling differential diagnosis of pancreatic cancer and chronic pancreatitis. When the pancreas is well visualized at US, the negative predictive value for pancreatic cancer is more accurate than that of CA 19-9 assessment and CT.

Admission control in diffserv-based next generation network (NGN) is still objective of the worldwide research (as in the IST projects DAIDALOS II and WEIRD) since the behavior of existing solutions does not comply with the requirements imposed by the infrastructure and the network operators. This paper describes the problem of edge-to-edge admission control in NGN, with a special attention to the admission of multicast traffic, and describes the possible way to design a decision algorithm. Moreover, this paper propose a fuzzy-logic based admission controller that is easy to implement, has a low computational cost and needs only small information, about the network controlled, to take its decision. Extensive OPNET simulations with multicast traffic validate the effectiveness of the proposed solution.

This paper analyses the current developments in terms of telecommunication networks design and investigates their limits concerning the control and management of multicast flows. An innovative approach is then introduced to extend the current architectures, so far mainly focused on unicast services, to handle multicast and broadcast services in a heterogeneous networks environment. The proposed solution aims at guaranteeing End-to-End QoS, efficiently handling the underlying network resources and integrating the emerging broadcast technologies in both intra and inter-domain scenarios. The paper is centered on the results achieved within the IST/FP6 Integrated Project DAIDALOS II (Designing Advanced network Interfaces for the Delivery and Administration of Location independent, Optimized personal Services ).

Aim of our study is to present the findings of parietal cortex alterations in patients affected by movement disorders. We observed 4 patients with movement disorders (3 parkinsonian syndromes, I diffuse dystonia) and MR evidence of cortical alterations, without additional cerebral lesions. MR was performed with a 0.5T unit, SE T1-w, TSE T2-w, and Turbo Fluid Attenuated Inversion Recovery (T-FLAIR) sequences on axial and coronal planes, contiguous slices and 5 mm slice thickness. In the parkinsonian patients, parietal atrophy was observed in 2 cases and fronto-parietal atrophy in I case; in all cases T-FLAIR sequences showed bilateral parietal cortex signal alteration. The patient with diffuse dystonia presented severe bilateral parietal atrophy with bilateral fronto-parietal signal alteration. Our findings are strongly suggestive for cortico-basal degeneration. The evidence of signal alteration within the cortex suggests a primary pathogenetic involvement of cortico-basal pathways.

Aim of this study was to evaluate the sensitivity of MR dynamic Bolus Tracking technique versus CT-cysterno graphy in Normal Pressure Hydrocephalus (NPH). Seven patients (age 64–76 yrs), clinically suspected of NPH, were retrospectively evaluated. They had been submitted to CT-cysternography, MR dynamic Bolus Tracking technique in the acqueduct (cardiac-gated flow direction evaluation by means of 12–16 FFE T2*-w acquisitions per cardiac cycle, on sagittal plane along the acqueduct, with presaturation perpendicular to the acqueduct) and finally to surgical evaluation and subsequent ventriculo-peritoneal shunt. MR showed in all cases altered cerebrospinal fluid (CSF) dynamics: 5 patients showed CSF reflux in the third ventricle during all cardiac cycle, in 2 patients an increased ejection rate through the acqueduct and into the cisterna magna was found. CT-cysternography showed CSF dynamics alterations only in 4 cases. MR dynamic Bolus Tracking technique has proven to be more sensitive than CT-cysternography in the evaluation of NPH. Even though this study has to be considered preliminary, we believe that this simple and noninvasive technique should be recommended when NPH is suspected.

An 85-year-old patient suffered from progressive deterioration (NYHA III) for several months. Cardiac disease was suspected. Echocardiography as well as a CT scan of the heart revealed a heart tumor to be the cause. Tumor staging was negative. After transvenous biopsy, the diagnosis of a Burkitt lymphoma could be established. Due to the advanced age of the patient, the intended surgical therapy was turned down and the patient was treated with 6 courses of a potentially therapeutic chemotherapy (CHOP scheme), which was well tolerated by the patient. The following CT scan showed a complete remission of the tumor. Six months after chemotherapy the patient is in NYHA stage I.

Among the anatomical and functional findings in cardiology, congenitally corrected transposition of the major vessels (ventricular inversion), bicuspid aortic valve and prolapse of the mitral valve with simultaneous mitral insufficiency have at least a potential for causing future problems. In such cases, regular cardiological checks or a further diagnostic work-up is to be recommended. The assessment of cardiac sounds can usually be correctly interpreted on the basis of the history, physical examination and auscultation. Among the electrocardiological findings, complete left bundle-branch block and prolongation of the QT segment, mandate clarification of a structural heart condition. Furthermore, in the event of ventricular extrasystoles, right-ventricular cardiomyopathy needs to be excluded. Such isolated conduction disorders as left-anterior fascicular block or right bundle-branch block are of no prognostic significance.

This retrospective study was performed to provide data on ventricular tachycardias (VT) with a cycle length longer than the initially programmed tachycardia detection interval (TDI) in patients with implantable cardioverter defibrillators (ICDs).It has been clinical practice to program a safety margin of 30 to 60 ms between the slowest spontaneous or inducible VT and the TDI.Baseline characteristics of 659 consecutive patients with ICDs were prospectively; follow-up information was retrospectively collected.During a mean follow-up of 31+/-23 months, 377 patients (57.2%) had at least one recurrent VT or ventricular fibrillation; 47 patients (7.1%) suffered 61 VTs above the TDI. The risk of a VT above the TDI ranged between 2.7% and 3.5% per year during the first four years after ICD implantation. The difference between the cycle length of the slowest VT before ICD implantation, spontaneous or induced, and the first VT above TDI was 108+/-58 ms. Fifty-four VTs (88.5%) above the TDI were associated with significant clinical symptoms (angina or palpitation 63.9%, heart failure 6.6% and syncope 8.2%). Six patients (9.8%) had to be resuscitated. Kaplan-Meyer analysis identified New York Heart Association class II or III (p = 0.021), ejection fraction0.40 (p = 0.027), spontaneous (p0.001) or inducible (p0.001) monomorphic VTs and the use of class III antiarrhythmic drugs (amiodarone, p0.001; sotalol, p = 0.004) as risk predictors of VTs above the TDI. The risk of recurrent VTs above TDI was 11.8%, 12.5% and 26.6% during the first, second and third year after first VT above TDI, respectively.The risk of VTs above the TDI is significantly increased in some patients, and many VTs above TDI cause significant clinical symptoms. A larger safety margin between spontaneous or inducible VTs and the TDI seems to be necessary in selected patients. This is in conflict with an increased risk of inadequate episodes and demands highly specific and sensitive detection algorithms in these patients.

Aims Benefits and complications of postoperative implantable cardioverter-defibrillator tests are controversial matters. This study sought to assess the necessity of defibrillation function tests after implantation. Methods and Results We retrospectively analysed 1007 implantable cardioverter-defibrillator tests in 587 systems and 556 patients. Nine hundred and thirty implantable cardioverter-defibrillator tests (89·4%) were routinely performed. Seventy-one tests (7%) were performed after a change in the antiarrhythmic drug regimen and six tests (0·60%) because of a suspected dysfunction of the implantable cardioverter-defibrillator. During routine tests, four systems (0·4%) failed to defibrillate the patient. However, in all but one test, abnormalities of the system had been observed before the test. After the addition of antiarrhythmic drugs, two of 71 implantable cardioverter-defibrillator systems (2·8%) failed to defibrillate the patient. One of six systems tested due to a suspected dysfunction failed to defibrillate the patient. During 16 tests (1·6%), complications occurred. Conclusions Our experience demonstrates that postoperative tests of the defibrillation function of implantable cardioverter-defibrillators rarely reveal dysfunctions. As testing is unpleasant for the patient and not free of complications, tests might be restricted to those patients in whom a dysfunction is suspected and to those patients in whom class I or class III antiarrhythmic drugs have been added to the antiarrhythmic drug regimen.

Skins of Potamotrygon reticulatus are light in color in vitro, exhibiting punctate melanophores. Alpha-Melanocyte stimulating hormone (EC(50) = 4.58 x 10(-9) M) and prolactin (EC(50) = 1.44 x 10(-9) M) darken the skins in a dose-dependent manner. The endothelins ET-1, ET-2 and ET-3, and the purines, ATP, and uracil triphosphate (UTP) were not able to induce either skin lightening or darkening. Forskolin and the calcium ionophore A23187 promoted a dose-dependent darkening response, whereas N(2), 2'-O-dibutyryl guanosine 3'-5'-cyclic monophosphate (db cyclic GMP), phorbol-12-myristate-13-acetate (TPA), and 1-oleoyl-2-acetyl-sn-glycerol (OAG) were ineffective. The maximal response obtained with the calcium ionophore A23187 was only 76% of maximal darkening. These results indicate that the cyclic adenosine 3'-5'-monophosphate (cAMP) pathway is probably involved in the pigment dispersion of P. reticulatus melanophores. Other experiments should be done to further investigate how cytosolic calcium may be physiologically increased, and the existence of a putative cross-talk between calcium and cAMP signals. In conclusion, the only hormones effective on P. reticulatus melanophores were prolactin and alpha-MSH. No aggregating agent has been shown to antagonize these actions. Prolactin effect on elasmobranch melanophores adds a novel physiological role to this ancient hormone. J. Exp. Zool. 284:485-491, 1999.

For the first time in the electron spin resonance (ESR) and peptide synthesis fields, a fully active spin-labeled peptide hormone was reported. The ESR spectra of this alpha-melanocyte stimulating hormone (alpha-MSH) analogue (acetyl-Toac0-alpha-MSH) where Toac is the paramagnetic amino acid probe 2,2,6,6-tetramethylpiperidine-1-oxyl-4-amino-4-carboxylic acid, suggested a pH-independent conformation and a more restricted movement comparatively to the free Toac. Owing to its equivalent biological potency in a skin pigmentation assay as compared to the native alpha-MSH and its unique characteristic (paramagnetic, naturally fluorescent and fully active), this analogue is of great potential for investigation of relevant physiological roles reported for alpha-MSH.

Primary Programming of Stability and Onset Criteria. Introduction: Inappropriate therapies are the most frequent adverse event in patients with implantable cardioverter defibrillators (ICDs). Most ICDs offer a stability criterion to discriminate ventricular tachycardia (VT) from atrial fibrillation and an onset criterion to discriminate VT from sinus tachycardia. The efficacy and safety of these criteria, if used immediately after implantation, is unknown. Methods and Results: In a case control study, 87 patients in whom stability and onset criteria had been activated immediately after ICD implantation were matched to 87 patients in whom these criteria had not been activated. The groups were matched for known predictors of inappropriate therapies. With stability and onset criteria off, 24 patients (28%) received inappropriate therapies due to atrial fibrillation (n = 14) or sinus tachycardia (n = 11); with stability and onset on, only 11 patients (13%) were treated by the ICD due to atrial fibrillation (n = 5) or sinus tachycardia (n = 7) (log rank: P = 0.029). Five patients suffered inappropriate therapies despite the fact that onset (n = 4) or stability (n = 1) criteria were not fulfilled once tachycardias continued for a prespecified duration. Only one patient experienced a failure to detect VT due to the onset criterion; none because of stability. Conclusion: The immediate use of stability and onset criteria after ICD implantation reduces inappropriate therapies due to atrial fibrillation and sinus tachycardia. Because of the potential for underdetection of VT, this approach should be limited to tachycardia rates hemodynamically tolerated by the patient.

Adults of Rana catesbeiana maintained for 4 days in 12:12 light/dark regimen exhibited a rhythmic color change of 24 hr. Under constant light, however, the rhythm disappeared, and the reflectance values gradually became greater, that is the animals became lighter. Under constant darkness, the rhythm was also abolished, but the animals tended to a darker color. On black background the skin darkening proceeded at a faster rate as compared to the skin lightening of animals adapting to a white background. The difference in color change rate suggests that the darkening responses are probably mediated by an increase in a circulating hormone, whereas skin lightening probably results from the serum level decrease of the same hormone. Most certainly, this hormone is alpha-MSH, as the in vitro assays demonstrated its high potency as a full darkening agonist (EC50 = 9 x 10(-10) M). Prolactin (EC50 = 7.7 x 10(-8) M) and endothelins 2 (EC50 = 1.3 x 10(-6) M) and 3 (EC50 = 4.8 x 10(-7) M) were also full agonists, but 100- to 1000-fold less potent than alpha-MSH. Isoproterenol, in the absence or presence of dibenamine, and endothelin-1 also elicited darkening responses in a dose-related manner, but reaching only 23% and 35% of the maximal darkening, respectively. Isoproterenol darkening effect was completely blocked by propranolol, confirming its action through beta-adrenoceptors. These results, taken together with the lack of lightening activity of norepinephrine on alpha-MSH-darkened skins, suggest that R. catesbeiana melanophores do not possess very active beta-adrenoceptors and lack alpha-adrenoceptors. On the other hand, the lightening agonist melatonin elicited only half-maximal dose-dependent reversal of MSH-induced darkening. Our results suggest that the chromatic rhythm is not endogenous, and most likely is determined by the light/dark cycle effect on alpha-MSH secretion.

This retrospective study was undertaken to provide information on occurrence, risk prediction and prevention of syncope in patients with an implantable cardioverter-defibrillator (ICD).ICDs effectively terminate ventricular tachycardia and fibrillation (VT/VF). Incapacitating symptoms, such as syncope, may still occur.We performed a retrospective analysis of data from 421 patients (clinical history, outpatient chart reviews and episode data) with mean (+/-SD) follow-up of 26 +/- 18 months.Of 421 patients, 229 (54.4%) had recurrent VT/VF, and 62 (14.7%) had syncope. The actuarial survival rate free of VT/VF was 58%, 45% and 37% and that for survival free of syncope was 90%, 85% and 81% at 12, 24 and 36 months after implantation, respectively. Once VT/VF had occurred, 76%, 68% and 62% of patients remained free of syncope during the following 12, 24 and 36 months, and 68%, 64% and 56% remained free of second syncope 12, 24 and 36 months after first syncope, respectively. In cases of syncope, the mean cycle length (CL) of VT was 251 +/- 56 ms. A low baseline left ventricular ejection fraction (LVEF), induction of fast VT (CL300 ms) during programmed ventricular stimulation and chronic atrial fibrillation (AF) were associated with an increased risk of syncope. If the LVEF was40%, fast VT had not been induced, and patients had no chronic AF; 96%, 92% and 92% of patients remained free of syncope after 12, 24 and 36 months, respectively. Once patients had a VT recurrence, syncope during the first VT and a high VT rate were the strongest risk predictors of future syncope.Identification of patients with an ICD with a low and high risk of syncope seems to be feasible and might help as a guide to driving restrictions in such patients.

We compared GRE T1 3D FS sequence with other acquisition techniques available on medium field strength MR units (.5 T) in patellofemoral cartilage studies.The imaging protocol scheduled Spin Echo (SE), Inversion Recovery (STIR), Gradient Echo (GRE), Turbo Spin Echo (TSE), Turbo-Inversion Recovery (Turbo-STIR), Gradient Spin Echo (GRASE) and Echo Planar (EPI) sequences, in some cases combined with Fat Suppression (FS) or Magnetization Transfer Contrast (MTC) sequences when suitable. In vitro studies were carried out for signal-to-noise ratio (SNR) evaluation, and in vivo on 10 healthy volunteers for contrast-to-noise ratio (CNR) evaluation between cartilage, bone marrow and fluid. The exams were carried out on MR equipment operating at .5 T, with 15 mT/m power gradients.In both in vitro and in vivo studies, GRE T1 3D FS sequences yielded better results in SNR and CNR than other sequences. The GRE T1 3D FS technique combines the advantages of the increased resolution of 3D images with the increased dynamic range of fat suppressed images, for better CNR between cartilage, fluid and bone marrow.GRE T1 3D FS sequences are the MR acquisition technique of choice in the assessment of the hyaline cartilage of the knee, even at medium field strength.

Postoperative tests of implantable cardioverter defibrillators (ICDs) are routinely performed to ensure appropriate defibrillation by the device. However, efficacy and complications of this procedure are unknown. To scrutinize the currently accepted indications to test the defibrillation function of the ICD we retrospectively analyzed 844 ICD-tests in 439 ICD-systems and 409 patients. 755 ICD-tests (89.4%) were routinely performed (57% before discharge and 43% during follow-up); 58 tests (6.9%) were performed after a change of the antiarrhythmic drug regimen, 24 tests (2.9%) after a revision of a part of the ICD-system, and seven tests (0.8%) because of a suspected dysfunction of the ICD. During routine-tests six ICD-systems (0.8%) failed to defibrillate the patient. However, in all but one test abnormalities of the ICD-system had been observed before the test. After addition of antiarrhythmic drugs, three of 58 ICD-systems (5.2%) failed to defibrillate the patient during the test (amiodarone: n = 2, flecainide: n = 1). Four of seven ICD-systems (57%) tested due to a suspected dysfunction failed to defibrillate the patient. After revisions of parts of the ICD-systems, ICD-tests never revealed a failure of defibrillation. During 16 ICD-tests (1.9%) complications occurred. The most frequent complications was inappropriate shocks (n = 10; 1.2%), the most severe one (transient) neurologic symptoms (n = 4; 0.48%). Our experience demonstrates that postoperative tests of the defibrillation function of ICDs rarely reveal ICD-dysfunction. As testing is unpleasant for the patient and not free of complications, tests might be restricted to those patients in whom an ICD-dysfunction is suspected (based on clinical presentation, results of chest-x-ray, testing of sensing signal and stimulation threshold) or class I or class III antiarrhythmic drugs have been added to the antiarrhythmic drug regimen.

The conventional Spin-Echo sequences have been the most used acquisition techniques on Magnetic Resonance Imaging (MRI) of the brain, since the beginning of 1990s. Recently, however, technological developments proposed such new fast acquisition techniques, with a dramatic reduction in acquisition time as Gradient Echo, Turbo Spin Echo, Gradient Spin Echo ed Echo Planar sequences. We investigated the comparative adequacy of the new fast sequences, in brain MR studies versus conventional sequences, on medium field strength MR equipment (.5 T). On in vitro exams S/N ratio was evaluated and on in vivo study C/N ratio between white substance grey substance and fluid were evaluated, in 15 healthy volunteers. All the exams were carried out on Philips NT5 Gyroscan MR unit operating at .5 T, with 15 mT/m power gradients. Both conventional and fast sequences Spin-Echo (SE), Inversion Recovery (IR), Gradient-Echo (GE), Turbo Spin-Echo (TSE), Gradient Spin-Echo (GRASE) and Echo Planar (EPI), all optimized to obtain T1, T2 and T1-IR weighted images, were performed. The sequences were evaluated separately comparing different acquisition techniques relative to the same type of contrast (T1, T2, and T1-IR). The results indicate the superiority of the fast acquisition techniques, both in terms of quality and acquisition times, except for T1-weighted images, where the conventional Spin-Echo sequences confirmed to be superior. In conclusion, the present study suggests that fast acquisition techniques can improve the conventional protocol of sequences, in the anatomical representation of the normal brain even with medium field strength equipment only on T2 and T1-IR weighted images. On T1-weighted imaging conventional SE acquisition technique is still the best choice. The time saving obtained with fast sequences can therefore be used for an overall improvement in the quality of images, and to apply accessory acquisition plans on routine exams.

The aim of this study is to define outcome predictors that might influence the prognosis and the mortality rate either of percutaneous drainage (DP) or open surgical drainage (DC) for abdominal abscesses. Seventy-one patients with 81 intra-abdominal abscesses were prospectively studied. They were 40 males and 31 females. Mean age was 47 +/- 15 years. Thirty-six (50.7%) patients had a simple abscess, while 35 (49.2%) had a complex abscess. Abscesses occurred most commonly in the sub-hepatic area, pelvic and para-colic space. Thirty-two (45%) patients had a percutaneous drainage, while 39 (54.9%) underwent an operative drainage management. Criteria for treatment selection were not randomized. However the two groups were statistically similar in respect to clinical features, cirrhosis, nutritional status, APACHE II scores), genesis and characteristics (simple, complex) of the abscesses. The treatment was considered successful when not requiring further drainage and the patient survived. Abdominal abscesses were cured in 53 (74.6) patients. In 13 cases (18.3%) a further drainage was necessary to obtain a complex resolution. Post drainage complications were significantly higher in the surgical drainage group (38.4% vs 12%, p0.05) because of the high incidence of wound infections. The overall mortality rate was 7%. Using an univariate analysis model, the only significant variable related to unsuccessful outcome in both the percutaneous and surgical group was abscess complexity (p0.005). Elderly (p0.005), malnutrition (p0.03), presence of cancer (p0.05), a high APACHE II score (p0.005) and the presence of a complex abscess (p0.02) were significantly identified as determinants of death.

BACKGROUND: Abdominal sonography, computed tomography (CT), angiography, and magnetic resonance (MR) imaging are the most widely used modalities for preoperative localization of insulinomas. CT and angiography are generally considered the techniques of reference, and the role of sonography and MR imaging in these patients is controversial. The purpose of this study was to compare these four modalities in a group of patients with pancreatic insulinoma and determine an effective radiological approach to this disease. METHODS: Twenty-eight patients with clinical and biochemical signs of pancreatic insulinoma underwent abdominal sonography, MR imaging at 0.5 T (spin echo technique), bolus dynamic CT, and digital subtraction angiography. Examinations were evaluated independently for the presence, size, and location of the lesions; preoperative diagnoses were compared with surgical findings based on palpation and intraoperative sonography. Tumoral vascularity was histologically graded. Sensitivities of the four imaging techniques were calculated and compared with the size, location, and vascularity of the tumors. Detection rates of combined techniques were finally determined. RESULTS: At surgery, 29 lesions in the 28 patients were found (range = 0.8-4.3 cm, average = 1.65 cm). Sensitivities of abdominal sonography. MR imaging, CT, and angiography were 79.3%, 65.5%, 44.8%, and 69% respectively. Correct localization of tumor was achieved in 96.6% of cases by a combination of sonography and MR imaging and in 72.4% of cases by using CT with angiography. CONCLUSION: In our experience, sonography and MR imaging performed well in the preoperative detection of pancreatic insulinoma. Therefore, we believe that the combination of abdominal sonography and MR imaging may represent the first radiological approach in clinically suspected insulinomas and that CT and angiography should be reserved for negative and/or doubtful cases.

We report our experience with the superselective embolization of iatrogenic vascular injuries. We used new coaxial catheters and new microcoils to assess their technical features and efficacy.Diagnostic angiography by catheterization of the main renal artery was performed in 7 patients with suspected renal vascular injury to detect injury presence and site. After super-selective catheterization of the feeding arteries with a coaxial catheter (Tracker 18), we performed embolization with platinum microcoils inserted using a coil pusher. The procedure efficacy was assessed at angiography and by comparing serum hemoglobin and hematocrit levels before and after embolization; posttreatment renal function was also studied.Selective embolization permitted complete occlusion of the arteries feeding the vascular injury in all patients, preserving as much parenchyma as possible. Hemoglobin and hematocrit levels were improved or unchanged after the maneuver (average hemoglobin level before embolization: 9.01 mg/dl versus 9.95 mg/dl after embolization; average hematocrit level before embolization: 27.3% versus 30.06% after embolization). We had no difficulty during microcoil insertion and the coaxial catheter was always stable.Superselective embolization of iatrogenic vascular injuries is an effective and definitive treatment. We recommend it in the patients with renal bleeding due to iatrogenic vascular injury after percutaneous diagnostic or therapeutic procedures.

To assess the role of interventional radiology in the conservative treatment of postoperative pancreatic fistula.A case of a high flow mixed entero-bilio-pancreatic fistula caused by dehiscence of pancreatic-jejunal anastomosis after duodenocephalopancreasectomy for endocrine neoplasm of the head of the pancreas,General Surgery Division and Diagnostic Radiology.Conservative treatment represents at the time being, due to the current possibilities in assisting critical patients and in controlling pancreatic secretory activity, the first choice in pancreatic fistula treatment. The effectiveness of this treatment depends on the severity of inflammatory disease of the pancreas. Clinical (Ranson, Glasgow, APACHE II) and radiological (Balthazar, Vernacchia) parameter evaluation is a critical step in therapeutic choice. Surgery should be used in patients with severe pancreatitis. Conservative treatment represents the first choice in stable and critical patients with mild pancreatitis.

In the last decade, magnetic resonance imaging (MRI) has played the main role in the study of diseases affect­ing the central nervous system (CNS). The main limita­tions of the first commercial units were predominantly represented by long acquisition times and low spatial resolution. The dramatic technological developments of the 1990’s have made it possible to overcome these lim­itations by selectively enhancing each parameter influ­encing the magnetic resonance (MR) signal, and have paved the way to functional studies with medium field units.

Background: To assess unenhanced and gadolinium-enhanced magnetic resonance (MR) imaging patterns of hepatocellular carcinoma (HCC) treated with transarterial chemoembolization (TACE). Methods: Thirty-two patients with 48 HCC lesions underwent MR imaging before and 15 days after TACE. Fifteen lesions were then surgically resected. The remaining 33 lesions were not removed and were followed up with MR imaging at 3, 6, 12, and 18 months after treatment. Spin echo (SE) T1- and T2-weighted and gadolinium-enhanced SE T1-weighted sequences were employed. Qualitative evaluation of signal intensity pattern of the treated lesions was performed in all cases. Histological evaluation and selective hepatic arteriography were considered the gold standard of the study for the 15 resected lesions and the 33 unresected lesions, respectively. Results: On follow-up enhanced T1-weighted images of the 15 resected lesions, seven showed no area of enhancement corresponding to complete necrosis at histologic examination. The remaining eight resected lesions showed areas of enhancement; in six of these cases, viable tumor tissue was found at histology; in the other two lesions, histologic examination revealed the presence of complete tumor necrosis. In the group of resected lesions, T2-weighted images showed no pattern characteristic of necrosis. In 24 of 33 unresected lesions, loss of enhancement on follow-up enhanced T1-weighted images was a characteristic finding, which correlated to devascularization at arteriography. Of these 24 lesions, 17 were completely hypointense on follow-up T2-weighted images; the remaining seven showed small foci of hyperintensity. The other nine unresected lesions showed enhanced portions on follow-up enhanced T1-weighted images, which corresponded to hyperintense areas on T2-weighted images. These findings correlated to persistence of hypervascular areas at arteriography. Conclusion: Gadolinium-enhanced T1-weighted MR imaging is a reliable method for evaluating the outcome of TACE treatment and is more accurate than unenhanced T2-weighted MR imaging.

To evaluate magnetic resonance (MR) imaging accuracy in the characterization of mural thrombi in abdominal aortic aneurysms (AAAs).Forty-five patients (37 men, eight women; mean age, 68 years) with an AAA with mural thrombus thicker than 1 cm at sonography underwent T1- and T2-weighted spin-echo MR imaging. The thrombi were prospectively classified as one of three signal intensity (SI) categories: category 1 corresponds to low SI on both T1- and T2-weighted images; category 2, high SI on T1-and T2-weighted images; and category 3, inhomogeneous SI with hyperintense areas on both T1- and T2-weighted images. During surgery, thrombi were classified as organized, unorganized, and partially organized. MR imaging and surgical findings were compared.SI category 1 corresponded to organized thrombi in 24 of 24 patients. Category 2 corresponded to unorganized thrombi in 11 of 11 patients. In category 3, focal hyperintense areas corresponded (both for presence and location) to unorganized portions of partially organized thrombi in 10 of 10 patients.MR imaging is accurate in AAA thrombus characterization.

A 10-year experience in surgical treatment of HCC in 122 cirrhotic patients has been reviewed in order to evaluate: perioperative mortality and morbidity, survival rates and prognostic variables by multiple-logistic analysis. Mortality rate declined from 7% in period 1983-88 to 2% in period 1989-92. Operative complications also decreased from 46% to 30%. The 3-year and 5-year overall survival rates were 42.6% and 23.3%. The 3-year and 5-year survival of patients who died only for HCC was 51.1% and 34.2% and the disease-free survival 30.6% and 19.1%. The good results of overall survival were vanished by the high rate of recurrence (19.1%). Multiple logistic regression analysis for the probability of mortality was significant for satellite nodules (RR 2.437), microvascular infiltration (RR 2.432), tumor size (RR 1.147); the model for the probability of recurrence was significant for microvascular infiltration (RR 2.290), satellite nodules (RR 2.280), lesions number (RR 2.216) and tumor size (RR 1.247).

BACKGROUND--The availability of implantable cardioverter-defibrillators (ICD) that are capable of antitachycardia pacing may lead to an increased use of ICDs in patients with haemodynamically tolerated ventricular tachycardia without a history of cardiac arrest. The frequency of potentially life-threatening fast ventricular tachycardias (cycle length < 250 ms) was investigated in patients who had a third generation ICD with endocardial leads implanted because they had haemodynamically tolerated ventricular tachycardia without a history of cardiac arrest. METHODS--Between January 1990 and October 1993, 50 patients (age (mean (SD)) 60 (11); ejection fraction 39 (16)%; 82% with coronary artery disease and 8% with dilated cardiomyopathy) with haemodynamically tolerated ventricular tachycardia (cycle length (mean (SD)) 348 (60) ms; range 250-500 ms) and without a history of cardiac arrest were treated with third generation ICDs that were capable of antitachycardia pacing. Fast ventricular tachycardia had been induced in 14 (28%) during baseline electrophysiological study. The benefit of ICD treatment was estimated as the difference between total mortality and the occurrence of fast ventricular tachycardia that would have been fatal if it had not been terminated. RESULTS--During follow up of 17 (12) months, 33 patients (66%) had a total of 3861 episodes of ventricular tachycardia. 91% of these episodes were terminated by antitachycardia pacing. 11 patients (22%) had episodes of potentially life-threatening fast ventricular tachycardia and 3 of these also had inducible fast ventricular tachycardia. One patient died suddenly 27 months after implantation. The difference between survival without fast ventricular tachycardia and total mortality was 9%, 12%, 27%, and 27% at 6, 12, 18, and 24 months, respectively. CONCLUSIONS--About a fifth of patients who had been given an ICD to treat haemodynamically tolerated ventricular tachycardia and who had no history of cardiac arrest experienced fast ventricular tachycardia during follow up requiring immediate cardioversion. Prospective studies are needed to investigate whether the prognosis of patients with a history of haemodynamically tolerated ventricular tachycardia without cardiac arrest is improved by ICD therapy.

Ultimately, implantable cardioverter-defibrillators (ICD) will one day be implantable like present pacemakers. However, due to the size of the pulse generator and the low defibrillation efficacy of monophasic shocks, only a few selected patients have been implanted transvenously-pectorally. Therefore, we have prospectively investigated whether a transvenous-pectoral approach is in general feasible with a new downsized ICD capable of delivering biphasic shocks. Out of 33 patients, 76% received a bipolar transvenous defibrillation lead system. In the first 13 consecutive patients, a randomized crossover study showed that this high efficacy was above all achieved by a superior defibrillation efficacy of the biphasic waveform in comparison to the monophasic waveform (69% vs. 23%; p = 0.03). Not a single patient could be defibrillated exclusively with the monophasic waveform. In a further 15 consecutive patients, a crossover study showed that a position of the transvenous anode within the Vena anonyma instead of the Vena cava superior is, in general, not superior (87% vs. 80%; p = 0.67). Only one patient could be exclusively defibrillated with the V. anonyma position. Intraoperatively, no complications occurred and all but one patient received a pectoral implantation of the pulse generator. Postoperatively, in five patients local complications related to the ICD system were seen; two needed a surgical revision. In two patients movements of the left shoulder joint were temporarily restricted. Thus, in the majority of patients a new downsized ICD capable of biphasic shocks can be implanted transvenously-pectorally like a pacemaker.

The purpose of this study was to assess Magnetic Resonance Imaging (MRI) patterns of hepatocellular carcinoma (HCC) treated with percutaneous ethanol injection (PEI) or Transarterial Chemoembolization (TACE) and, consequently, the potential role of MR Imaging in the follow-up of these lesions. HCC treated with PEI. Thirty-one patients with a single small HCC lesion underwent MR Imaging at 0.5 T before and after PEI. In all cases before and after treatment contrast enhanced Computed Tomography (CT) and US-guided fine-needle biopsy were performed. Twenty-seven of 31 HCC lesions in which complete tumor necrosis was obtained with PEI showed homogeneous hypointensity on SE T2-weighted MR images. This feature corresponded to an unenhanced and low-attenuation area on follow-up contrast-enhanced CT scans. All these lesions were negative for malignant cells at fine-needle biopsy follow-up. In four HCCs, high-signal areas on SE T2-weighted images and high-attenuation areas on contrast-enhanced CT scans were observed, suggesting the presence of residual tumor tissue; these lesions were positive for malignant cells at 6-month fine-needle biopsy. In each case, incomplete tumor necrosis was confirmed at pathologic examination of the surgical specimen. HCC treated with TACE. Twenty-one patients with a total of 36 HCC lesions underwent plain and Gadolinium-enhanced MR Imaging before and after TACE. 10 HCC lesions were later surgically resected; 26/36 lesions underwent MR, CT and angiographic follow-up. At short-term follow-up exams (15-30 days), hypointensity was present on enhanced SE T1 weighted sequences in those lesions (5/10) in which complete tumor necrosis was histologically confirmed. In the remaining 5/10 HCC lesions, persistent viable tumor portions were found at pathology. These areas corresponded to areas on hyperintensity of Gadolinium-enhanced SE T1-weighted images. Hypointensity on both SE T2-weighted and enhanced SE T1-weighted images was a characteristic pattern on long-term follow-up MR images in 21/26 unresected lesions; this finding was correlated with devascularization at angiography; the presence of hyperintense areas on SE T2 weighted and enhanced SE T1-weighted images corresponded to the persistence of hypervascular (viable) areas at angiography.

Inflammatory abdominal aortic aneurysms (IAAA) represent a peculiar variant compared with the common atherosclerotic origin of aortic aneurysms. Between January 1988 and March 1992, 111 aneurysmectomies were performed at our institution: 98 elective and 13 emergency procedures. In 10 cases (all males, mean age 68.5) an IAAA was found. 8/10 of those patients operated upon electively were studied preoperatively with MRI. All the IAAA but one were correctly identified preoperatively. Identification of IAAA with MRI in these cases improved the surgical approach. In conclusion, patients with IAAA can be operated upon safely especially if a preoperative diagnosis is present. MRI greatly improves our ability to characterize non invasively IAAA.

In December 1986 we attempted direct chemical litholysis using methyl-tertiary-butyl-ether (MTBE) in a sixty-year-old man with severe ischemic heart disease who had suffered frequent episodes of biliary colic due to a radiolucent gallstone. MTBE was infused for a total of 17 hrs over a period of 5 days; however the gallstone diameter remained unchanged. The patient was subsequently cholecystomized and chemical analysis revealed that the gallstone was a pigment stone. The need for accurate prediction of gallstone composition before beginning an invasive, such as MTBE infusion, is emphasized.

We prospectively compared 3D Gadolinium-enhanced and 3D-TOF MR angiographic acquisition techniques on the main cerebral arteries and cortical branches.

20 pts affected by chronic cerebrovascular disease (10) and demyelinating disease (10) were studied by means of conventional MRI and T2*-w dynamic scans (6 slices acquired in 2“, 60 dynamic scans obtained for each slice, total acquisition time ?120”) with the aim of evaluating wether different patterns could be defined between infarctions and demyelinations. 5 subjects were excluded for different reasons. Signal intensity (SI) and transit time (BPAT = Bolus Peak Arrival Time) values were calculated from ROIs positioned on affected and contralateral non affected areas in each pt. In the group affected by demyelinating diseases, data from pathological ROIs were not significantly different from the contralateral, although the basal value of the lesions started from more elevated levels. On the contrary, pts affected by vascular lesions showed significantly different values of SI between pathological ROIs and apparently normal contralateral brain (χ2 test, p

Signal intensity of temporal lobes was studied in eighteen patients with Alzheimer's disease. Fluid attenuated inversion recovery (FLAIR) sequence and fast spin-echo (TSE) sequence were employed. Diagnosis of Alzheimer's disease was achieved with clinical tests. In 11 patients (61%) pathological temporal lobe hyperintensities were detected. FLAIR sequence was more sensitive (61%) than TSE (28%).