bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis of Initial Slow Waves (ISWs) at the Seizure Onset in Patients with Drug Resistant Temporal Lobe Epilepsy
Authors: Bragin Anatol , Claeys Pieter , Vonck Kristl , Van Roost Dirk , Wilson Charles , Boon Paul , Engel Jerome
Published: June 2007

Summary:  Rationale: The goal of this study is to analyze initial slow waves (ISWs) at seizure onset in patients with refractory temporal lobe epilepsy. ISWs are a specific type of ictal EEG pattern characterized by a slow wave at the seizure onset followed by low voltage fast activity.

Methods: Investigations were carried out on 14 patients from the UCLA hospital (USA) and 10 from the Ghent University Hospital (Belgium) implanted with depth and grid electrodes for localization of the epileptogenic zone.

Results: Sixty‐one seizures in the UCLA group and 30 seizures in the Ghent group were analyzed. Fourteen UCLA and seven Ghent patients had ISWs at seizure onset. The duration of ISWs varied between 0.3 to 6.0 s and maximum amplitude varied from 0.2 to 1.4 mV. ISWs in three of 14 UCLA patients (30% of seizures) had a consistent positive polarity at the deepest contacts that were located in the amygdala, hippocampus, or entorhinal cortex and reversed polarity outside of these brain areas (ISWs1). ISWs in 11 of 14 UCLA patients (70% of seizures) had negative polarity at the deepest electrodes and their amplitude increased toward the recording contacts located in the white matter or neocortex (ISWs2). All ISWs from the seven Ghent patients were negative in the depth contacts (ISWs2) and positive on grid electrodes at the cortical surface. ISWs1 were associated with EEG spikes at the onset and on increase in amplitude of 10–20 Hz sinusoidal activity. In contrast, ISWs2 were associated with suppression of EEG amplitude, an increase in frequency in the range of 20–50 Hz, and did not have EEG spikes at the onset. Multiunit neuronal activity showed strong synchronization of neuronal discharges during interictal spikes, but multiunit synchronization was not obvious during ISWs2.

Conclusion: The existence of EEG spikes and phase reversal with ISWs1 indicates this type of seizure may be triggered by hypersynchronous neuronal discharges; however, seizures with ISWs2 at the onset may be triggered by different mechanisms, perhaps nonneuronal.
Simplifying Alcohol Assessment: Two Questions to Identify Alcohol Use Disorders
Authors: Vinson Daniel C. , Kruse Robin L. , Seale J. Paul
Published: June 2007

Background: Previous work has validated a single question to screen for hazardous or harmful drinking, but identifying those patients who have an alcohol use disorder (AUD) among those who screen positive is still time consuming. We therefore sought to develop and validate a brief assessment instrument using DSM‐IV criteria for use in primary care medical practice.

Methods: Four cross‐sectional surveys of past‐year drinkers. The developmental sample included patients presenting to emergency departments with an acute injury. The second sample, from the same study, was recruited by random‐digit dialing. The third sample was recruited in 5 family medicine practices in Georgia. The fourth sample was the National Epidemiologic Survey on Alcohol and Related Conditions. Interviews with the first 3 samples used the Diagnostic Interview Schedule. The National Epidemiologic Survey on Alcohol and Related Conditions (NESARC) used the Alcohol Use Disorder and Associated Disabilities Interview Schedule.

Results: Two constructs with promising test characteristics were identified: recurrent drinking in hazardous situations and drinking more than intended. Among those who screened positive with the single question in the developmental sample (N=959), if either of the 2 items was positive, the sensitivity for current AUD was 95% and the specificity was 77%. In the second (N=494) and third (N=280) samples, the sensitivity was 94 and 95% and the specificity was 62 and 66%, respectively, among those with a positive screen. In the NESARC sample, including those with at least 1 occasion in the past year of drinking 5 or more drinks (N=7,890), the sensitivity and specificity were 77 and 86%, respectively.

Conclusions: The sensitivity and specificity of these 2 items across 4 samples suggest that they could be formulated into 2 questions, potentially providing busy primary care clinicians with an efficient, reasonably accurate assessment instrument to identify AUD among those patients who screen positive with the single screening question.
Osteoblast Differentiation Is Enhanced in Rotary Cell Culture Simulated Microgravity Environments
Authors: Ko Y. Joon , Zaharias Rebecca S. , Seabold Denise A. , Lafoon John , Schneider Galen B.
Published: June 2007

Purpose:
As the aging population increases, more people will become reliant on regenerative dental medicine for implant therapy. The objective of this study was to test the hypothesis that 3D rotary cell culture (RCC) environments created by simulated microgravity would enhance osteogenic gene expression using integrin mediated pathways.

Materials and Methods:
Human embryonic palatal mesenchymal (HEPM, ATCC 1486) pre‐osteoblasts were cultured in either RCC to create 3D environments or in 2D monolayers for 72 hours. Gross phenotypic analysis was performed using Alizarin Red S staining for calcium and microscopy. Real‐time PCR analysis was used to detect differences in osteoblast gene expression. Aggregates developed in 3D RCC environments were treated with or without antibody to the collagen‐I integrin receptor α2β1 to determine whether this molecular pathway might contribute to the development of a mineralized matrix.

Results:
Microscopic analysis demonstrated that RCC environments promoted 3D aggregate formation by 72 hours without any scaffold. The mass appeared osseous‐like with a white, shiny, translucent surface. The center was amorphous with areas of vacuolization, tubule‐like structures, and fibrous‐like extensions. Real‐time PCR data showed that 3D environments enhanced osteogenic gene expression as compared with 2D monolayer culturing conditions. At 72 hours, changes in levels of osteogenic gene expression were noted. Cbfa1, a necessary transcription factor for osteoblast differentiation, was expressed 33% higher (p= 0.26); Collagen 1, 69% higher (p= 0.05); Osterix, 49% higher (p= 0.001); and BSPII, 54% higher (p= 0.001) than osteoblasts cultured for 72 hours in standard 2D monolayer conditions. When cultured in the presence of collagen α2β1 integrin receptor antibody, 3D aggregates had decreased levels of mineralization as compared with non‐treated aggregates.

Conclusion:
RCC enhances osteoblast differentiation using integrin mediated pathways.
Measuring the Radiopacity of Luting Cements, dowels, and Core Build‐up Materials with a Digital Radiography System Using a CCD Sensor
Authors: Rasimick Brian J. , Gu Steven , Deutsch Allan S. , Musikant Barry Lee
Published: June 2007

Purpose:
This study assessed the radiopacity of five luting cements, five dowels, and five core build‐up materials using two target distances.

Materials and Methods:
Materials were analyzed using a modified version of ISO protocol 4049. samples 1 mm thick were digitally radiographed alongside a stepwedge of aluminum alloy 1100 using a Trophy RVG‐4 CCD sensor and 70 kVp X‐ray generator. The gray‐scale values of the stepwedge and sample were converted to X‐ray absorbencies. The relationship between X‐ray absorbance and aluminum thickness was linear for thicknesses less than 10 mm and followed a power‐law relationship above 10 mm. These relations were used to convert the absorbencies of the samples into aluminum thicknesses. The radiopacity data was subjected to ANOVA/Student–Newman–Keuls testing.

Results:
All materials were more radiopaque than equivalent thicknesses of aluminum. Each product category contained a wide range of radiopacities. Syringe‐dispensed materials tended to be less radiopaque than materials dispensed by mechanically assisted syringe or mixed by hand (p < 0.01). Target distance did not affect the measured radiopacity so long as the exposure time was suitably adjusted (p= 0.86).

Conclusions:
All luting cements and core materials met or exceeded the ISO minimums. The tested metal‐reinforced glass ionomer core build‐up materials were extremely radiopaque. Some publications suggest that excessively radiopaque core materials can hinder a clinician's ability to spot voids or marginal defects.
Dimensional Change of Laser‐Welded Gold Alloy Induced by Heat Treatment
Authors: Watanabe Ikuya , Chang Jennifer , Chiu Yvonne
Published: June 2007

Purpose:
This study examined the effects of laser welding and heat treatment on the dimensional change of cast gold alloy frameworks.

Materials and Methods:
Pairs of cast gold alloy plates were matched, fixed in a jig, and welded in a laser‐welding machine at constant welding parameters. The specimens were welded unilaterally (on one surface) or bilaterally (on two surfaces) with five spots as follows: two ends fixed/unilaterally welded (A); two ends fixed/bilaterally welded (AA); one end fixed/unilaterally welded (B); two ends fixed/welded on one surface and then one end fixed/welded on the opposite surface (AB); or one end fixed/bilaterally welded (BB). The dimensional change was determined by measuring the gap between the jig base and one end of the specimen after each welding application. Dimensional change was also measured after two different heat treatments (softening and hardening). The results were analyzed using a two‐way ANOVA and Duncan's test (p < 0.05).

Results:
The dimensional change of the specimens fixed at only one end on either surface (AB, B, and BB) was higher compared with the two ends‐fixed specimens (A and AA) after laser welding. The heat treatments also increased the dimensional change in all groups except for the B group. The dimensional change was similar for each fixing method between the two types of heat treatment.

Conclusions:
The method of fixing the specimens in the jig significantly affected the amount of dimensional change of the gold alloys. The heat treatments of the laser‐welded specimens increased the dimensional change by releasing the residual stress.
Prosthodontists in Private Practice: Current and Future Conditions of Practice in the United States (Part I)
Authors: Nash Kent D. , Pfeifer David L.
Published: June 2007

Purpose: The purpose of this study was to use data from surveys of prosthodontists to examine the current conditions and characteristics of prosthodontists in private practice in the United States.

Materials and Methods: Characteristics of prosthodontists and conditions of practice are based on the 2002 Survey of Prosthodontists and the 2005 Survey of Prosthodontists. Both surveys were conducted by the American College of Prosthodontists. Several characteristics of private practice/practitioners are estimated including age, gender, number of patient visits, hours in the practice, employment of staff, and financial conditions (gross receipts, expenses of the practice, and net income of prosthodontists)

Results:
In 2004, the average age of private practitioners was 50 years. Years since graduation from dental school averaged 23.4 years, and years since completion of residency was 18.3 years. Prosthodontists spent an average of 35.7 hours per week in the office and 29.5 hours treating patients. In 2004, the average gross revenue per owner of a private practice reached $782,130, and mean net income was $258,490. The largest percentage of prosthodontist time was spent providing six procedures including fixed prosthodontics, implant services, complete dentures, operative care, diagnosis, and partial dentures.

Conclusion:
The United States spends about $1.8 billion on prosthodontic services provided by prosthodontists in private practice. Prosthodontists spend $1.1 billion dollars in expenses and treat an estimated 1.1 million patients per year.
A Technique to Obtain Stable Centric Occlusion Records Using Impression Plaster
Authors: Stamoulis Kostas , Hatzikyriakos Andrew Eleftherios
Published: June 2007

Recording the maxillomandibular relationship is often a challenge. In situations where there is vertical support but no horizontal stability, and the space between posterior teeth of opposing jaws is not adequate for an interocclusal record, impression plaster can be used. Despite limited clinical use, impression plaster is known for its stability. With this technique, the interocclusal record is obtained by applying the material to the buccal surfaces of the posterior teeth, resulting in a precise and stable cast relationship.
Alignment and Interaction in a Sociocognitive Approach to Second Language Acquisition
Authors: ATKINSON DWIGHT , CHURCHILL ETON , NISHINO TAKAKO , OKADA HANAKO
Published: June 2007

This article argues for the crucial role of alignment in second language acquisition, as conceptualized from a broadly sociocognitive perspective. Byalignment, we mean the complex processes through which human beings effect coordinated interaction, both with other human beings and (usually human‐engineered) environments, situations, tools, and affordances.

The article begins by summarizing what we mean by a sociocognitive approach to second language acquisition. We then develop the notion of alignment, first in terms of general learning/activity and next in relation to second language (L2) learning. Following that, we provide an extended example of alignment‐in‐action, focusing on the coordinated activities of a Japanese junior high school student and her tutor as they study English in their sociocognitively constructed world. Next, we speculate on possible uses of the alignment concept in L2 research and teaching, and finally we conclude by restating our claim—that alignment is a necessary and crucial requirement for L2 development.
Russian Emotion Vocabulary in American Learners’ Narratives
Authors: PAVLENKO ANETA , DRIAGINA VIKTORIA
Published: June 2007

This study compared the uses of emotion vocabulary in narratives elicited from monolingual speakers of Russian and English and advanced American learners of Russian. Monolingual speakers differed significantly in the distribution of emotion terms across morphosyntactic categories: English speakers favored an adjectival pattern of emotion description, and Russian speakers a verbal one. Advanced American learners of Russian shifted from the adjectival to the verbal pattern in Russian and thus began approximating the usage of native speakers of Russian. At the same time, the data revealed 6 areas where learner usage differed from the monolingual Russian corpus: morphosyntactic transfer from the first language (L1), semantic transfer from the L1, greater use of adverbial constructions, absence of a language‐specific verb frequently used by native Russian speakers, violations of appropriateness of sociolinguistic register, and a significantly lower proportion of emotion word tokens.
The U.S. National Security Strategy: Policy, Process, Problems
Authors: Doyle Richard B.
Published: June 2007

Since 1986, presidents have been required to submit an annual National Security Strategy (NSS). Recent years have seen a proliferation of national strategies of other kinds, linked in part to the NSS. The National Security Council, led by the national security advisor and employing its committee system and the interagency process, develops the NSS. The integration of all the necessary elements within the NSS involves an opaque and irregular set of rolling negotiations among national security principals. The 2006 NSS is best viewed in comparison to the 2002 version, which was issued in the immediate aftermath of 9/11. It stipulates that the United States is at war with transnational terrorism fueled by a perversion of Islam and proposes stable democracy as the primary solution, supported by aggressive efforts to control the proliferation of weapons of mass destruction and the option of taking preemptive military action. Criteria for assessing national security strategies can be process oriented or results based.
Developments in the Law: Garcetti v. Ceballos and the Workplace Freedom of Speech Rights of Public Employees
Authors: Roberts Robert
Published: June 2007

On May 30, 2006 the Supreme Court handed down a 5–4 decision in the case of Garcetti v. Ceballos, announcing that “when public employees make statements pursuant to their official duties, they are not speaking as citizens for First Amendment purposes, and the Constitution does not insulate their communications from employer discipline.” Previously, the Court had held in Pickering v. Board of Education (1968) that the First Amendment’s protection of freedom of speech generally prohibited public employers from firing or disciplining employees for speaking out on matters of “public concern.” The Pickering decision established a two‐part test that first required federal courts to determine whether the employee had spoken out on a matter of public concern and then whether the disruptive impact of the employee’s statement justified the disciplinary action. This article argues that the Garcetti decision may deter many public employees from disclosing governmental inefficiency and misconduct and presenting dissenting viewpoints on matters of clear public concern. Consequently, the decision may make it more difficult for the leadership of public agencies to uncover inefficiency and misconduct.
Putting the Resource‐Based View of Strategy and Distinctive Competencies to Work in Public Organizations
Authors: Bryson John M. , Ackermann Fran , Eden Colin
Published: June 2007

A key to the success of public organizations is their ability to identify and build capacity, particularly their distinctive competencies, in order to produce the greatest value for key stakeholders. This article grounds this proposition in the resource‐based view of organizations and presents a method for identifying and making use of distinctive competencies in the form of a “livelihood scheme”—a business model appropriate for the public sector—that links distinctive competencies to organizational aspirations and goals. The case of a major public sector training and consultancy unit that is part of the United Kingdom’s National Health Service is used as illustration. A number of conclusions are offered in the form of a set of propositions tied to the resource‐based view and related research issues. The results contribute to both public strategic management theory and practice.
Adjusting Fiscal Decentralization Programs to Improve Service Results in Bulgaria and Romania
Authors: Guess George M.
Published: June 2007

Fiscal decentralization programs are works in progress, and expenditure roles often need to be adjusted to improve service delivery. The Balkan countries of Romania and Bulgaria, both needed for accession to the European Union in 2007, must demonstrate positive results from their fiscal decentralization programs in the social services area. Focusing on social service delivery, this paper explores how the design of fiscal decentralization programs, in the form of assigning intergovernmental expenditure roles and responsibilities, affects service performance. The authors conclude that fiscal decentralization requires the proper assignment of authority to match expenditure responsibilities and the policy and administrative capacity to carry them out.
New Technologies Stuck in Old Hierarchies: The Diffusion of Geo‐Information Technologies in Dutch Public Organizations
Authors: Vonk Guido , Geertman Stan , Schot Paul
Published: June 2007

Some 25 years after the introduction of the first geo‐information technologies in public organizations, strategies to manage their diffusion are still inadequate. This is problematic in light of the new generation of geo‐information technologies that has become available and aims to invest in these new information technologies in order to advance e‐government. This study questions how strategies for diffusion of geo‐information technologies in public planning organizations can be improved. It shows that classic top‐down management often enhances informal diffusion activities that deviate from the formal diffusion strategy. A knowledge management approach, in which geo‐information specialists and planners participate in the formation of diffusion policies, can enhance the quality of the formal strategy, thereby preventing deviation and informal diffusion activities. The authors recommend that public planning organizations use this knowledge to improve their diffusion strategies for geo‐information technologies.
The “Long‐Sheath” Technique in Percutaneous Aortic Balloon Valvuloplasty
Authors: SERRUYS PATRICK W. , DI MARIO CARLO , KONING RENE , DE FEYTER PIM J , BEATT KEVIN J. , VAN DEN BRAND MARCEL
Published: June 2007

A new 100 cm long 16.5 French valvuloplasty introducer was used in 12 consecutive patients (mean age 73 years, five males and seven females) undergoing aortic balloon valvuloplasty for severe aortic stenosis. The long‐sheath was introduced into the ascending aorta along the stiff part of an exchange guidewire. The valvuloplasty procedure, which included a complete diagnostic catheterization in three patients, lasted 113 ± 47 min (211 ± 81 min in the previous 18 procedures performed with a conventional approach, P < 0.05). Introduction of balloon catheters (3 × 12 mm trefoil balloon in the 12 cases and 2 × 19 mm bifoil balloon in 2 of these cases) was possible in all patients and an increased stability of the balloon during inflation was observed. No systemic embolization or vascular complications occurred at the puncture site. The long‐sheath technique appears to be a valuable adjunct for aortic valvuloplasty in that it provides easier and quicker access for even the largest balloons and additional support and stability during balloon inflation. In our experience, this reduced the practical difficulties and the duration of the procedure.
Determinants of Left Ventricular Functional Recovery After Thrombolytic Therapy and/or Immediate Coronary Angioplasty in Acute Myocardial Infarction
Authors: LANGBURD ALAN B. , TOPOL ERIC J. , SEREIKA SUSAN M. , BATES ERIC R. , WALTON JOSEPH A. , WORDEN RAY , PITT BERTRAM , O'NEILL WILLIAM W.
Published: June 2007

To determine the effect of thrombolytic therapy and/or immediate coronary angioplasty (PTCA) on left ventricular function, 129 patients with acute transmural myocardial infarction were retrospectively studied. Treatment strategies included thrombolytic therapy alone (n = 29), PTCA alone (n = 41), and combined thrombolytic therapy and PTCA (n = 59). Left ventricular ejection fraction (LVEF) and infarct zone regional wall motion (RWM) were determined from contrast ventriculography obtained acutely and at day 7–10. In the overall group, there was a 2 ± 9% increase in LVEF (p < 0.02) and a 0.7 ± 1.2 SD/chord increase in RWM (p < 0.0001) between day 1 and day J‐10. Patients with a patent infarct vessel at day 7–10 had a more significant change (Δ) in LVEF (3 ± 8 vs −5 ± 9%, p = 0.0002) and RWM (0.8 ± 1.2 vs 0.1 ± 1.0 SD/chord, p < 0.02) than patients with an occluded vessel. Patients with a residual stenosis < 70% at day 7–10 manifested a greater ΔLVEF (3 ± 8vs‐5 ± 9%, p < 0.01) and ΔRWN (0.9 ± 1.2 vs 0.1 ± 1.0 SD/ chord, p < 0.05) than patients who were occluded. There was a negative correlation between residual stenosis and ΔRWM (p < 0.04). Patients treated < 3 hours after symptom onset demonstrated a more significant ΔRWM when compared to patients treated ≥ 3 hours (1.0 ± 1.3 vs 0.5 ± 1.1 SD/chord, p < 0.04). Patients treated with combined thrombolytic therapy and PTCA were observed to have a greater ARWM than patients treated with thrombolytic therapy alone (0.8 ± 1.2 vs 0.2 ±0.9 SD/chord, p < 0.05). Patients with an LVEF > 40% demonstrated a more significant ΔLVEF than patients; ± 40% (7 ± 8vs 1 ± 8%, p < 0.007). A significant improvement in ΔLVEF was noted only in patients with an anterior infarction when compared to patients with an inferior infarction. Age, sex, presence of multivessel disease, history of prior myocardial infarction, initial patency of the infarct vessel, and presence of collaterals had no effect on left ventricular function. Stepwise multiple regression identified residual stenosis, time to treatment, and the degree of initial global impairment as the major joint predictors of ventricular functional recovery. (J Interven Cardiol 1988:1:3)
Subselective Intracoronary Access Guide Catheters for use with the ProbeTM Balloon on a Wire Coronary Dilatation Device
Authors: LINDSEY RICHARD L. , KLEIST PAUL C.
Published: June 2007

Subselective coronary access guide catheters are described for use with the ProbeTM balloon on a wire coronary dilatation device. These access catheters provide the following advantages over the “naked” ProbeTM: (1) Guide catheter stabilization, (2) Lesion access, (3) Lesion visualization, (4) Lesion crossing, and (5) Lesion protection. The Probe/access catheter system was used in 51 patients on 132 lesions (average 2.6 lesions/patient; range 1–8 lesions/patient) of which 116 (88%) were dilated successfully. Failures tended to be in total occlusions or in eccentric subtotal occlusions that could not be crossed with the ProbeTM tip wire. No patient required emergency coronary bypass. One patient sustained a small myocardial infarction within 24 hours of the procedure. One patient developed hemopericardium after rupture of a small branch coronary artery. One patient died from intracerebral bleeding due to thrombolytic and anticoagulant therapy. The ProbeTM access catheter system has several advantages over the ProbeTM device alone, and future developments can be expected to extend these benefits. (J Inter‐ven Cardiol 1989:2:1)
Retrograde Mitral Valvuloplasty—A Further Approach to Balloon Commissurotomy
Authors: SIEVERT H. , KRÄMER P. , KALTENBACH M. , KOBER G.
Published: June 2007

Mitral valve balloon dilatation usually requires transseptal puncture. We performed a mitral valve dilatation without transseptal puncture, introducing guidewires and balloons exclusively from the arterial side in a 37‐year‐old woman with post‐rheumatic mitral stenosis. Three months later, pulmonary artery pressure had decreased from 60/35 to 40/20 mmHg and the enddiastolic pressure gradient from 20 to 8 mmHg. The mitral valve area increased from 1.3 to 2. 3 cm2. The severely disabled patient was asymptomatic following the procedure. This case demonstrates the possibility of performing retrograde balloon dilatation of the mitral valve without transseptal puncture.
Pattern of Restenosis after Percutaneous Transluminal Coronary Angioplasty of Bifurcation Stenoses
Authors: PINKERTON CASS A. , SLACK JOHN D. , NASSER WILLIAM K. , PINTO RODGER P. , CENTER DIANE , ORR CHARLES M. , VANTASSEL JAMES , WALLER BRUCE
Published: June 2007

Bifurcation stenoses have been recognized to be at a “high risk” for acute closure during percutaneous transluminal coronary angioplasty. Development of advanced techniques using simultaneous (“kissing”) balloon inflation or sequential balloon inflations, using two guidewires to preserve access to both branches while avoiding the trauma produced by inflating two balloons in a small artery simultaneously, has allowed safe and effective dilatation of bifurcation stenoses. Little is known, however, about the restenosis rate and pattern of bifurcation stenoses. This article reports on 44 patients who were treated successfully using the sequential inflation technique on their bifurcation stenoses. A total of 88 lesions were dilated. Restenosis occurred in 25 of the 88 lesions (28%) within 8.5 ± 2.25 months. Eleven patients had restenosis in one vessel while seven patients had restenosis in both branches (18 of 44–41%). All 18 underwent a second PTCA attempt and 15 patients had successful repeat PTCA. Thus, the primary restenosis rate in bifurcation stenosis is acceptably low, occurring in both branches in a minority of cases (7/18). The total restenosis rate is no greater than expected with single vessel PTCA. Repeat PTCA is usually easily accomplished with good secondary success, aided by the fact that the majority of the restenoses involve only one rather than both branches of the bifurcation stenosis. (J Interven Cardiol 1989:2:3)
Left Main Coronary Angioplasty: Assessment of a “Risk Score” to Predict Acute and Long‐Term Outcome
Authors: SAMSON MICHEL. , PLANTE SYLVAIN. , MEESTER HANNIE. , RENSING BENNO J. , DE FEYTER PIM J. , SERRUYS PATRICK W.
Published: June 2007

Due to the recent emergence of adjunctive techniques such as cardiopulmonary bypass support, left main angioplasty may become more routinely applied in the near future. In order to choose the best possible therapy, a precise risk assessment will be desirable. Twenty‐two left main angioplasties were thus reviewed and patients were divided in two groups according to a risk score adapted from a previously published jeopardy score. Group I included patients with a risk score ≤ 6 and group II patients with a risk score > 6. A cutoff criterion of six points was chosen because it represents the maximal amount of myocardium put at jeopardy from a single coronary stenosis. The success rate of the procedure was 77% and was similar in both groups. Of the 12 patients in group I, two patients underwent in‐hospital bypass surgery and one of them died. Among the ten patients of group II, one sustained a myocardial infarction, three underwent acute surgery, and one patient died postoperatively. After a mean follow‐up of 41 months, the total mortality rate was 17% in group I and 30% in group II. The long‐term event‐free survival rate was 75% in group I and 10% in group II (P = 0.004). The risk score was found to be a potentially important predictor of sustained success (long‐term success: 4.4 ± 2.9 vs no long‐term success: 8.3 ± 3.4; P = 0.01), although sophisticated statistical analysis was limited by the small number of patients. Thus, in patients with a low risk score, angioplasty seems to be an appropriate treatment while it appears that surgery should remain the standard therapy for patients with a calculated high risk score. However, the clinical significance of this new risk score remains to be determined with more elaborate statistical analysis applied to a larger number of patients.
Clinical Experience with the Combination of an Antitachycardia Pacemaker (Orthocor II) and the Implantable Cardioverter‐Defibrillator in Drug‐Refractory Ventricular Tachycardia
Authors: MALONEY JAMES D. , PINSKI SERGIO L. , MASTERSON MARTIN. , WILKOFF BRUCE. , SIMMONS TONY. , MORANT VICTOR A. , GOLDING LEONARD. , CASTLE LON W.
Published: June 2007

Four men with remote myocardial infarction, left ventricular dysfunction, aborted episodes of sudden death, and recurrent ventricular tachycardia (VT) slowed but not controlled by drugs (mean five trials) were treated with an automatic antitachycardia pacemaker (ATP) (Orthocor II) and an implantable cardioverter‐defibrillator (ICD). Cardiac electrophysiological evaluation had disclosed that the VT could be reliably terminated with decremental extrastimuli. Two defibrillation patches and two epimyocardial sensing electrodes were used. The ATP was implanted separately using a bipolar endocardial electrode. During follow‐up three patients died. One from hepatitis B at two months, and two from sudden cardiac death at 10 and 13 months. One of these deaths was related to ICD battery depletion, the other to a high defibrillation threshold. One patient is alive after 41 months. During the first year postimplant, 359 episodes of VT occurred and there were 105 ICD discharges. The rate and duration of VT episodes terminated by the ICD were 208 ± 7 bpm and 22 ± 9 seconds; and of VT episodes terminated by the ATP were 158 ± 15 bpm and 6 ± 1.8 seconds, respectively. Deleterious device‐to‐device interactions could be avoided. All patients required full antiarrhythmic drug therapy. Conclusions: (1) In highly selected patients, drug‐resistant VT can be terminated by antitachycardia pacing unperceived by the patient; (2) An ICD must provide reliable back‐up defibrillation capability for rapid or accelerated VT or ventricular fibrillation; (3) this initial experience demonstrates the feasibility of utilizing the Orthocor II ATP in combination with an ICD as therapy for refractory clinically recurrent VT.
Percutaneous Coronary Laser Thermal Angioplasty of Accelerated Transplant Atherosclerosis
Authors: HEILBRUNN STEVEN M. , DEUTSCH EZRA , KLEAVELAND J. PATRICK , ALPERN JEFFREY B. , KOLFF JACOB
Published: June 2007

Percutaneous coronary laser thermal angioplasty was successfully performed on a 57‐year‐old white male with a total occlusion of the left anterior descending coronary artery. The patient was the recipient of an orthotopic heart transplant 3 years previously secondary to end‐stage heart disease due to idiopathic dilated cardiomyopathy. The lesion was reduced from 100% to 33% residual stenosis following a single 4‐second pulse of 12 W of continuous wave Nd:YAG (neodymium:yttrium‐aluminum‐garnet) laser energy delivered to a distal thermal probe. Conventional balloon angioplasty reduced the remaining stenosis to 22%, without evidence of vessel perforation, spasm, dissection, or embolization of debris. This case represents the first known use of thermal laser energy as an adjunct to conventional angioplasty for the treatment of coronary artery disease in a heart transplant recipient. Additional studies are indicated to determine the clinical role of this procedure in relation to established methods of revascularization for the treatment of accelerated transplant atherosclerosis.
Double‐Umbrella Device for Transvenous Closure of Patent Ductus Arteriosus and Atrial Septal Defect: First Experience
Authors: BABIC UROS U. , GRUJICIC SRETEN , POPOVIC ZORAN , DJURISIC ZORAN , VUCINIC MIHAJLO , PEJCIC PETAR
Published: June 2007

A new device for transcatheter closure of heart defects was constructed and used to close a patent ductus arteriosus (PDA) in seven adult patients and an atrial septal defect (ASD) in six adult patients. The device consisted of two self‐opening umbrellas and a piece of Ivalon. A Dacron patch was sewn on the “male” umbrella for the ASD closure. The device required a 9 Fr introducing venous sheath for PDA and a 14 Fr sheath for the ASD. The venoarterial (right femoral vein‐PDA or ASD‐left femoral artery) long wire track was arranged. The “male” umbrella and the Ivalon were inserted transvenously one after another, advanced over the. long wire across the PDA or ASD and extruded into the aorta or left atrium, respectively. The “female” umbrella was advanced transvenously over the long wire into the pulmonary artery (for PDA) or into the right atrium (for ASD). The metal conus on the long wire was used to pull the “male” umbrella while a special stiff pusher was used to bring the “female” umbrella to the “male” umbrella along the long wire. By these means the umbrellas interlocked at the defect level and closed it. The long wire was then removed through the left femoral artery. Protrusion of the interlocked device through the PDA occurred in one patient and through the ASD in two patients. In all three patients the device was kept on the wire until surgery and an early postrelease device embolization was avoided. In all other patients the defects were successfully closed. The follow‐up of 3–27 months was uneventful in all patients. These results indicate that the described procedure is effective and safe, and warrants further clinical trial. (J Interven Cardiol 1991; 4:283–294)
Coronary Directional Atherectomy: Rescue for Failed Balloon Angioplasty and Treatment of Complicated Lesions
Authors: VON POELNITZ A. , BACKA D. , BAURIEDEL G. , NERLICH A. , HOEFLING B.
Published: June 2007

Balloon angioplasty of the coronaries is still limited by the problems of acute complication and restenosis. Percutaneous directional atherectomy was conceived as a method to remove obstructive material from within the vessel. After encouraging results were obtained in peripheral vessels, coronary atherectomy has been selectively performed in 25 patients with lesions either not well suited for PTCA (n = 11), or as a bail‐out after resistant (n = 2) or failed PTCA (n = 12). Twenty‐one LAD lesions (4 ostial, 13 proximal, 2 mid, and 2 bifurcation) and four right coronary artery (RCA) lesions with a mean length of 9 ± 6 mm (19 eccentric, and 6 concentric) could be effectively reduced from 90%± 72% to 18%± 22%. Seventy‐five percent of rescue cases could be spared emergency bypass operation. At 6 months, angiographic restenosis has been documented in 3 out of 11 patients studied to date (27%). Histologically, rescue procedures resulted in the removal of obstructing plaque material and only minimal thrombus. The occurrence of two perforations during rescue procedures, although clinically insignificant, emphasizes the need for judicious excision. In summary, directional atherectomy appears to be useful to treat lesions not well suited for PTC A, and important as a bail‐out method after failed PTCA.
Laser Angioplasty in Miniature Swine: Advantages of a Modified Fiber Tip Delivery System
Authors: WHITE CHRISTOPHER J. , RAMEE STEPHEN R. , SAMSON GENE , KOTMEL ROBERT F. , BANKS ALAN K. , AITA MICHAEL
Published: June 2007

Laser angioplasty using a spherical lensed fiber‐tip laser delivery catheter and a 200 μm bare silica fiber tip was performed in occluded atherosclerotic iliac arteries of miniature swine. Group I consisted of 8 animals with 11 totally occluded arteries in which the bare silica fiber was used. Group II included 22 animals with occlusive lesions in 41 arteries in which the silica lens tip was used. In vivo laser angioplasty was performed in both groups using an argon ion laser delivering 2 to 3 watts of power in 1 to 5 second intervals. Successful recanalization occurred in 7/11 (64%) in group I arteries and 35/41 (85%) in group II arteries. Vascular perforation occurred in 36% (4/11) in group I compared to 10% (4/41) in group II (P < 0.05). Mechanical perforation due to the bare fiber alone accounted for 50% of the perforations in group I and did not occur with the silica lens‐tip device (group II). We conclude that the atraumatic lensed fiber is more effective in recanalizing occlusive lesions and is a safer delivery system than the bare silica fiber.
Early and Long‐Term Results of Catheter Ablation in Patients with Incessant Ventricular Tachycardia
Authors: TRAPPE HANS‐JOACHIM , KLEIN HELMUT , WENZLAFF PAUL , R. LICHTLEN PAUL
Published: June 2007

Catheter ablation of sustained monomorphic ventricular tachycardia (VT) with high energy DC shock (360–400 J) was performed in 11 patients with incessant VT (duration > 24 hours), refractory to antiarrhythmic drugs, and DC cardioversion. There were ten patients with coronary disease and one patient had dilated cardiomyopathy. Direct current energy was delivered at the earliest endocardial activation in six patients (group I) or at the area of slow conduction in five patients (group II). Incessant VT was terminated by DC ablation in nine patients (82%). After the ablation procedure VT remained inducible in four patients in group 1 (67%) and in one patient (20%) in group II. Two patients in group II had to go to emergent surgery. During the mean follow‐up of 31 ± 26 (1–66) months nonfatal VT recurrences occurred in five patients in group I and in one patient in group II.
Controlled Release of Heparin Reduces Neointimal Hyperplasia in Stented Rabbit Arteries: Ramifications for Local Therapy
Authors: ROGERS CAMPBELL , EDELMAN ELAZER R.
Published: June 2007

Percutaneous coronary angioplasty is limited by neointimal hyperplasia and restenosis. Endovascular stenting has been proposed as a possible means of limiting this process. In practice stents have achieved early patency but are beset by early thrombosis and late restenosis. Heparin administered locally or systemically reduces smooth muscle cell hyperplasia following arterial injury in animals. Balloon‐expandable stainless steel stents were placed in de‐endothelialized rabbit iliac arteries to determine whether heparin released locally from perivascular matrices could reduce stent induced thrombosis and intimal hyperplasia. All animals received oral aspirin beginning 1 day prior to implantation and an IV bolus of heparin at balloon injury and stent placement. Heparin releasing ethylene‐vinyl acetate copolymer matrices were placed adjacent to the stented portion of the artery in the treated group of rabbits. Thrombosis was evident in 30% of ten control arteries 14 days after stent placement and was reduced to 0% in nine segments receiving local heparin therapy (P < 0.05). Intimal hyperplasia was present in all experimental arterial sections, but total intimal area normalized for induced injury was reduced at 14 days from 12.6 ± 0.9 mm2 in controls, to 6.8 ± 1.0 mm2 in treated arteries (P < 0.001). Our results with perivascular drug administration may shed some light on the pathobiology of the vascular response to endovascular stent insertion and might assist in the design of novel means for enhancing the utilization of angioplasty and other interventional procedures.
Acronyms in Angioplasty and Restenosis: A Summary of Recent and Ongoing Clinical Randomized Trials
Authors: LANDAU CHARLES , FAXON DAVID P.
Published: June 2007

Trials that pertain to angioplasty and restenosis are a major focus of clinical research in cardiology at present. Investigators, especially those involved in multicenter studies, have become experts in the derivation of acronyms to identify these trials. Meant to capture the spirit of the trial and the attention of those reading the eventual publication of the results, these abbreviations have proliferated in recent times. This article summarizes the major trials with acronym titles, spells out what they stand for, defines what was investigated, and reviews the reported results. (J Interven Cardiol 1992; 5:29–37)
Temporary Stents: The ACS RX Flow Support Catheter
Authors: ABDELMEGUID ALAA E. , WHITLOW PATRICK L.
Published: June 2007

Although permanent stents have been successfully used as bail‐out devices in the treatment of abrupt occlusion, the risk of stent thrombosis and of bleeding complications, as well as the cost of a prolonged hospitalization, have been deterrents to their universal acceptance. Temporary stents were conceived to provide internal scaffolding of the coronary arteries, which could stabilize occlusive dissections, yet still allow the stent to be removed before the time of peak incidence of subacute thrombosis. The ACS RX flow support catheter is a prototype temporary stent which has been recently evaluated in phase I and II clinical trials. The device is effective in improving angina score, coronary flow, and decreasing residual stenosis when used in cases of suboptimal percutaneous interventional results. However, the incidence of major complications and the need for adjunctive percutaneous interventions remain significant. Further studies are needed to define the optimal time of cage expansion as well as the clinical, anatomical, and procedural factors that predict efficacy and safety of this new device.
Long‐Term Clinical and Angiographic Follow‐Up After Placement of Palmaz‐Schatz Coronary Stent: A Single Center Experience
Authors: KIMURA TAKESHI , TAMURA TAKASHI , YOKOI HIROYOSHI , NOBUYOSHI MASAKIYO
Published: June 2007

The purpose of this study is to evaluate long‐term clinical and angiographic follow‐up results after placement of the Palmaz‐Schatz stent and angiographic follow‐up results of repeat interventions for stent restenosis. From June 1990 to September 1993, the Palmaz‐Schatz stent was placed in 411 patients, 427 lesions. Follow‐up angiography was performed in 307 lesions at 3–6 months and in 189 lesions at 1 year. Palmaz‐Schatz scent implantation resulted in 97.2% procedure success and 94.6% clinical success. Stent thrombosis was observed in 2.2%. Angiographic restenosis rate was 16.3% at 3–6 months study. At 1 year study, “new” restenosis occurred only in 2.3%. Minimal lumen diameter did not change between 6 months and 1 year (2.32 ± 0.51 mm vs 2.30 ± 0.54 mm). With the mean follow‐up interval of 22 ± 9 months, cardiac event‐free survival was achieved in 74.3%. Among 50 lesions with restenosis, stem restenosis occurred diffusely in 15 lesions (30%), focally inside the stent in 22 lesions (44%) and focally at the scent border in 13 lesions (26%). Repeat interventions were performed in 35 lesions. Restenosis at 3 months after repeat intervention was demonstrated in 9 (32.1%) out of 28 lesions restudied. Restenosis rate after repeat intervention for diffuse stent restenosis was significantly higher than that for focal instent restenosis (75% vs 7.7%). Palmaz‐Schatz stent implantation was associated with a high initial success rate and a low late restenosis rate. Luminal renarrowing did not occur beyond 6 months up to 1 year.
Experience with a 6 French Double Loop Catheter for Right Coronary Angiography
Authors: EL GAMAL MAMDOUH , BRACKE FRANK , BILTAGIU SHERIF EL , PEELS KATHINKA , VELDHUIJZEN FRANK , VAN GELDER BERRY
Published: June 2007

A 6Fr double loop diagnostic catheter was developed for angiography of the right coronary artery and tested in 101 patients. Its primary use was employed in 60 patients, and after failure of a 6Fr right Judkins diagnostic catheter in 41 patients. Primary use was successful in 56 out of 60 patients (93%);four failures were cannulated with 6Fr right Judkins diagnostic catheters. After failure of 6Fr right Judkins diagnostic catheters, 36 out of 41 patients (88%) were successfully cannulated with 6Fr double loop diagnostic catheters. Causes of failure of 6Fr right Judkins diagnostic catheters were: inadequate torque control in 24 patients, because of tortuosity of femoro iliac arteries or aorta;dilatation of the ascending aorta, abnormal origin or course of the initial segment of the right coronary artery in 17 patients. Three out of five patients in whom right Judkins diagnostic and double loop diagnostic catheters failed to intubate the right coronary artery were successfully cannulated with 7Fr diagnostic catheters (right Judkins one patient;El Gamal one patient;right coronary bypass one patient). Conclusion: 6Fr double loop diagnostic catheters increased the success rate of right coronary angiography after failure of 6Fr right Judkins diagnostic catheters.
Intraarterial Doppler Flow Measurements During Renal Artery Endovascular Stent Deployment: Abolition of Resting Impedance to Blood Flow
Authors: BATES MARK C. , DORROS GERALD , KUMAR KRISHNA
Published: June 2007

This communication details the first reported case of renal artery intraarterial pulse wave Doppler obtained prior to, and following primary stenting of a renal artery stenosis. Doppler wave forms were recorded proximal, within, and distal to the lesion and reported with the angiographic and hemodynamic results. The changes in average and maximal peak velocities following stent deployment continued the abolition of the resting transstenotic gradient and renal artery stenosis. Intraarterial pulsed wave Doppler complements angiography and translesional gradient measurements as a physiological marker of a successful procedure.
Interventional Cardiology in New Zealand
Authors: ORMISTON JOHN A. , SMITH WARREN M.
Published: June 2007

Death rates from coronary heart disease in New Zealand are among the highest in the world although they have steadily fallen since a peak in 1968. The health care system is largely publicly funded with most cardiologists being salaried, although there has been a growth in fee‐for‐service private practice. Waiting times in public hospitals for bypass surgery can be years for chronic stable angina. The publicly funded health care system is being reformed. In 1993 there were in New Zealand, for a population of just less than 3.5 million: 6,227 coronary angiograms; 1,365 percutaneous interventions; and 1,513 coronary artery bypass only operations. The percutaneous intervention rate was 391 per million. There has been an increase in new device use so that in Auckland 11% of percutaneous interventions involved new devices.