Publications by authors named "Moussa Saleh"

21 Publications

  • Page 1 of 1

Increased Inpatient Mortality for Cardiovascular Patients During the First Wave of the COVID-19 Epidemic in New York.

J Am Heart Assoc 2021 08 13;10(16):e020255. Epub 2021 Aug 13.

Department of Cardiology Northwell Health Manhasset NY.

Background The acuity and magnitude of the first wave of the COVID-19 epidemic in New York mandated a drastic change in healthcare access and delivery of care. Methods and Results We retrospectively studied patients admitted with an acute cardiovascular syndrome as their principal diagnosis to 13 hospitals across Northwell Health during March 11 through May 26, 2020 (first COVID-19 epidemic wave) and the same period in 2019. Three thousand sixteen patients (242 COVID-19 positive) were admitted for an acute cardiovascular syndrome during the first COVID-19 wave compared with 9422 patients 1 year prior (decrease of 68.0%, <0.001). During this time, patients with cardiovascular disease presented later to the hospital (360 versus 120 minutes for acute myocardial infarction), underwent fewer procedures (34.6% versus 45.6%, <0.001), were less likely to be treated in an intensive care unit setting (8.7% versus 10.8%, <0.001), and had a longer hospital stay (2.91 [1.71-6.05] versus 2.87 [1.82-4.95] days, =0.033). Inpatient cardiovascular mortality during the first epidemic outbreak increased by 111.1% (3.8 versus 1.8, <0.001) and was not related to COVID-19-related admissions, all cause in-hospital mortality, or incidence of out-of-hospital cardiac deaths in New York. Admission during the first COVID-19 surge along with age and positive COVID-19 test independently predicted mortality for cardiovascular admissions (odds ratios, 1.30, 1.05, and 5.09, respectively, <0.0001). Conclusions A lower rate and later presentation of patients with cardiovascular pathology, coupled with deviation from common clinical practice mandated by the first wave of the COVID-19 pandemic, might have accounted for higher in-hospital cardiovascular mortality during that period.
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http://dx.doi.org/10.1161/JAHA.120.020255DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8475060PMC
August 2021

Clinical predictors of heart block during atrioventricular nodal reentrant tachycardia ablation: A multicenter 18-year experience.

J Cardiovasc Electrophysiol 2021 06 21;32(6):1658-1664. Epub 2021 Apr 21.

Department of Cardiac Electrophysiology, Northwell Health, New York, New York, USA.

Background: Catheter ablation is considered the first-line treatment of symptomatic atrioventricular nodal reentrant tachycardia (AVNRT). It has been associated with a risk of heart block (HB) requiring a pacemaker. This study aims to determine potential clinical predictors of complete heart block as a result AVNRT ablation.

Methods: Consecutive patients undergoing catheter ablation for AVNRT from January 2001 to June 2019 at two tertiary hospitals were included. We defined ablation-related HB as the unscheduled implantation of pacemaker within a month of the index procedure. Use of electroanatomic mapping (EAM), operator experience, inpatient status, age, sex, fluoroscopy time, baseline PR interval, and baseline HV interval was included in univariate and multivariate models to predict HB post ablation.

Results: In 1708 patients (56.4 ± 17.0 years, 61% females), acute procedural success was 97.1%. The overall incidence of HB was 1.3%. Multivariate analysis showed that age more than 70 (odds ratio [OR] 7.907, p ≤ .001, confidence interval [CI] 2.759-22.666), baseline PR ≥ 190 ms (OR 2.867, p = .026, CI 1.135-7.239) and no use of EAM (OR 0.306, p = .037, CI 0.101-0.032) were independent predictors of HB.

Conclusion: Although the incidence of HB post AVNRT ablation is generally low, patients can be further stratified using three simple predictors.
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http://dx.doi.org/10.1111/jce.15037DOI Listing
June 2021

Use of general anesthesia to suppress incessant atrial fibrillation in a patient undergoing ablation for supraventricular tachycardia.

HeartRhythm Case Rep 2021 Feb 19;7(2):87-90. Epub 2020 Nov 19.

Department of Cardiology, Arrhythmia Services, North Shore University Hospital, Manhasset, New York.

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http://dx.doi.org/10.1016/j.hrcr.2020.11.007DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7897722PMC
February 2021

Atrial fibrillation is an independent predictor for in-hospital mortality in patients admitted with SARS-CoV-2 infection.

Heart Rhythm 2021 04 22;18(4):501-507. Epub 2021 Jan 22.

Department of Cardiology, Northwell Health, New York, New York.

Background: Atrial fibrillation (AF) is the most encountered arrhythmia and has been associated with worse in-hospital outcomes.

Objective: This study was to determine the incidence of AF in patients hospitalized with coronavirus disease 2019 (COVID-19) as well as its impact on in-hospital mortality.

Methods: Patients hospitalized with a positive COVID-19 polymerase chain reaction test between March 1 and April 27, 2020, were identified from the common medical record system of 13 Northwell Health hospitals. Natural language processing search algorithms were used to identify and classify AF. Patients were classified as having AF or not. AF was further classified as new-onset AF vs history of AF.

Results: AF occurred in 1687 of 9564 patients (17.6%). Of those, 1109 patients (65.7%) had new-onset AF. Propensity score matching of 1238 pairs of patients with AF and without AF showed higher in-hospital mortality in the AF group (54.3% vs 37.2%; P < .0001). Within the AF group, propensity score matching of 500 pairs showed higher in-hospital mortality in patients with new-onset AF as compared with those with a history of AF (55.2% vs 46.8%; P = .009). The risk ratio of in-hospital mortality for new-onset AF in patients with sinus rhythm was 1.56 (95% confidence interval 1.42-1.71; P < .0001). The presence of cardiac disease was not associated with a higher risk of in-hospital mortality in patients with AF (P = .1).

Conclusion: In patients hospitalized with COVID-19, 17.6% experienced AF. AF, particularly new-onset, was an independent predictor of in-hospital mortality.
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http://dx.doi.org/10.1016/j.hrthm.2021.01.018DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7825902PMC
April 2021

Association between regional distributions of SARS-CoV-2 seroconversion and out-of-hospital sudden death during the first epidemic outbreak in New York.

Heart Rhythm 2021 02;18(2):215-218

Department of Cardiac Electrophysiology, Lenox Hill Hospital, New York, New York.

Background: Increased incidence of out-of-hospital sudden death (OHSD) has been reported during the coronavirus 2019 (COVID-19) pandemic. New York City (NYC) represents a unique opportunity to examine the epidemiologic association between the two given the variable regional distribution of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in its highly diverse neighborhoods.

Objective: The purpose of this study was to examine the association between OHSD and SARS-CoV-2 epidemiologic burden during the first COVID-19 pandemic across the highly diverse neighborhoods of NYC.

Methods: The incidences of OHSD between March 20 and April 22, 2019, and between March 20 and April 22, 2020, as reported by the Fire Department of New York were obtained. As a surrogate for viral epidemiologic burden, we used percentage of positive SARS-CoV-2 antibody tests performed between March 3 and August 20, 2020. Data were reported separately for the 176 zip codes of NYC. Correlation analysis and regression analysis were performed between the 2 measures to examine association.

Results: Incidence of OHSD per 10,000 inhabitants and percentage of SARS-CoV-2 seroconversion were highly variable across NYC neighborhoods, varying from 0.0 to 22.9 and 12.4% to 50.9%, respectively. Correlation analysis showed a moderate positive correlation between neighborhood data on OHSD and percentage of positive antibody tests to SARS-CoV-2 (Spearman ρ 0.506; P <.001). Regression analysis showed that seroconversion to SARS-CoV-2 and OHSD in 2019 were independent predictors for OHSD during the first epidemic surge in NYC (R = 0.645).

Conclusion: The association in geographic distribution between OHSD and SARS-CoV-2 epidemiologic burden suggests either a causality between the 2 syndromes or the presence of local determinants affecting both measures in a similar fashion.
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http://dx.doi.org/10.1016/j.hrthm.2020.11.022DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7831674PMC
February 2021

Surface unipolar electrogram characteristics to predict site of origin of outflow tract arrhythmias using noninvasive mapping.

J Cardiovasc Electrophysiol 2021 02 6;32(2):391-399. Epub 2021 Jan 6.

Department of Cardiac Electrophysiology, Northwell Health-Lenox Hill Heart and Lung, New York, New York, USA.

Background: Noninvasive electroanatomic mapping (NIEAM) demonstrate patterns of depolarization that are useful in identifying the chamber of origin (COO) in outflow tract ventricular arrhythmias (OTVA). However, its use in predicting exact site of origin (SOO) has not yet been validated.

Methods: NIEAMs (CardioInsight, Medtronic) from 40 patients (age 62.5 ± 2.6) undergoing ablation for OTVA were reviewed for diagnostic accuracy in predicting the SOO. Earliest arrhythmia breakout and directionality of earliest instantaneous unipolar electrograms (uEGMs) on NIEAMs were evaluated subjectively by two observers for quality and amplitude. Sites with most negative earliest uEGMs on right and left ventricular outflow tracts, as well as epicardial surface were manually identified. Using NIEAM-based activation timing of the lateral mitral annulus and basal septum COO was identified for each OTVA. Predictions of SOO using NIEAMs was compared with true SOO from invasive study. NIEAMs SOO predictions were compared with subjective 12 lead electrocardiogram (ECG) review by two observers.

Results: Review of arrhythmia breakout and signal directionality had poor diagnostic value in predicting SOO in OTVA (50.6% and 49.4%, 56.6% and 43.4%, respectively) and underperformed compared with ECG interpretation (59.1% and 80.5%). After excluding uEGMs with poor characteristics, the uEGM with most negative amplitude at the COO was predictive of the true SOO with 96.4% sensitivity and specificity.

Conclusion: We propose a stepwise approach when interpreting NIEAMs for OTVA where patterns of activation are evaluated first to determine the COO, followed by identification of the site with most negative amplitude instantaneous uEGM to determine SOO.
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http://dx.doi.org/10.1111/jce.14857DOI Listing
February 2021

Intracardiac echocardiography guided nonocclusive balloon cryothermal applications to achieve antral isolation during pulmonary vein isolation.

J Interv Card Electrophysiol 2021 Nov 27;62(2):329-336. Epub 2020 Oct 27.

Department of Cardiac Electrophysiology, Northwell Health - Lenox Hill Heart and Lung, 100 East 77th Street 2 Lachman, New York, NY, 10075, USA.

Objective: Ablation for atrial fibrillation (AF) requires electrical isolation of the pulmonary veins (PV) by wide-area circumferential PV antral isolation (PVAI). Cryoballoon ablation delivers cryoenergy circumferentially after occlusion of the PV by the cryoballoon; thus, it is likely that the level of isolation, determined by adequate balloon-tissue contact, depends on PV anatomy. We sought to examine the need for nonocclusive segmental cryoballoon ablation in achieving antral isolation, describe methods of accurate visualization of the cryoballoon using intracardiac echocardiography (ICE), and provide data on biophysical characteristics of an effective nonocclusive cryothermal lesion.

Methods: Forty consecutive patients undergoing catheter ablation with a second-generation 28-mm cryoballoon and electroanatomic mapping (EAM) were included. Balloon was visualized with ICE, and its location was registered in EAM using available technology (CARTOSOUND, Biosense Webster). Need for delivery of nonocclusive lesions was based on level of isolation post occlusive lesions.

Results: Nonocclusive lesions to PVAI was required in 26 of 40 patients (65%) or 46 out of 148 veins (31%). Left PVs > 19.4 ± 2.9 mm, right superior PV > 20.2 ± 4.7mm, funnel-shaped PVs, and right PVs not converging to a carina were more likely to require nonocclusive lesions to achieve an antral level of isolation. Projection of balloon contour on EAM using CARTOSOUND successfully predicted level of isolation by voltage mapping.

Conclusion: Nonocclusive cryoballoon applications are commonly required to achieve antral isolation. Use of ICE can be helpful in determining the accurate location of the balloon and in predicting the level of isolation by voltage map.
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http://dx.doi.org/10.1007/s10840-020-00905-9DOI Listing
November 2021

Safely Administering Potential QTc Prolonging Therapy Across a Large Health Care System in the COVID-19 Era.

Circ Arrhythm Electrophysiol 2020 11 1;13(11):e008937. Epub 2020 Oct 1.

Department of Cardiology (M.S., J.G., D.C., S.E.M., L.M.E.), The Feinstein Institutes for Medical Research, Northwell Health, NY.

Background: The severe acute respiratory syndrome coronavirus 2 (SARs-CoV-2) has resulted in a global pandemic. Hydroxychloroquine±azithromycin have been widely used to treat coronavirus disease 2019 (COVID-19) despite a paucity of evidence regarding efficacy. The incidence of torsade de pointes remains unknown. Widespread use of these medications forced overwhelmed health care systems to search for ways to effectively monitor these patients while simultaneously trying to minimize health care provider exposure and use of personal protective equipment.

Methods: Patients with COVID-19 positive who received hydroxychloroquine±azithromycin across 13 hospitals between March 1 and April 15 were included in this study. A comprehensive search of the electronic medical records was performed using a proprietary python script to identify any mention of QT prolongation, ventricular tachy-arrhythmias and cardiac arrest.

Results: The primary outcome of torsade de pointes was observed in 1 (0.015%) out of 6476 hospitalized patients with COVID-19 receiving hydroxychloroquine±azithromycin. Sixty-seven (1.03%) had hydroxychloroquine±azithromycin held or discontinued due to an average QT prolongation of 60.5±40.5 ms from a baseline QTc of 473.7±35.9 ms to a peak QTc of 532.6±31.6 ms. Of these patients, hydroxychloroquine±azithromycin were discontinued in 58 patients (86.6%), while one or more doses of therapy were held in the remaining nine (13.4%). A simplified approach to monitoring for QT prolongation and arrythmia was implemented on April 5. There were no deaths related to the medications with the simplified monitoring approach and health care provider exposure was reduced.

Conclusions: The risk of torsade de pointes is low in hospitalized patients with COVID-19 receiving hydroxychloroquine±azithromycin therapy.
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http://dx.doi.org/10.1161/CIRCEP.120.008937DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7668332PMC
November 2020

Anatomic predictors of recurrence after cryoablation for atrial fibrillation: a computed tomography based composite score.

J Interv Card Electrophysiol 2021 Aug 30;61(2):293-302. Epub 2020 Jun 30.

Division of Cardiac Electrophysiology, Department of Cardiology, Northwell Health- Lenox Hill Heart and Lung, 100 East 77th Street, 2 Lachman, New York, NY, 10075, USA.

Background: Effective pulmonary vein isolation (PVI) with cryoablation depends on adequate occlusion of pulmonary veins (PV) by the cryoballoon and is therefore likely to be affected by PV and left atrial (LA) anatomical characteristics and variants. Thus, the objective of this study was to investigate the effect of LA and PV anatomy, evaluated by computed tomography (CT), on acute and long-term outcomes of cryoablation for atrial fibrillation (AF).

Methods: Fifty-eight patients (64.72 + 9.44 years, 60.3% male) undergoing cryoablation for paroxysmal or early persistent AF were included. Pre-procedural CT images were analyzed to evaluate LA dimensions and PV anatomical characteristics. Predictors of recurrence were identified using regression analysis.

Results: 60.3% of patients had two PVs on each side with separate ostia, whereas 29.3% and 10.3% had right middle and left common PVs, respectively. The following anatomic characteristics were found to be independent predictors of recurrence: right superior PV ostial max:min diameter ratio > 1.32, left superior PV ostial max:min diameter ratio > 1.2, right superior PV antral circumference > 69.1 mm, right inferior PV antral circumference > 61.38 mm, right superior PV angle > 22.7°. Using these factors, LA diameter and right middle PV, a scoring model was created for prediction of "unfavorable" LA-PV anatomy (AUC = 0.867, p = 0.000009, score range = 0-7). Score of ≥ 4 predicted need for longer cryoenergy ablation (p = 0.039) and more frequent switch to radiofrequency energy (p = 0.066) to achieve PVI, and had a sensitivity of 83.3% and specificity of 82.5% to predict clinical recurrence.

Conclusion: CT-based scoring system is useful to identify "unfavorable" anatomy prior to cryo-PVI, which can result in procedural difficulty and poor outcomes.
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http://dx.doi.org/10.1007/s10840-020-00799-7DOI Listing
August 2021

Inpatient use of mobile continuous telemetry for COVID-19 patients treated with hydroxychloroquine and azithromycin.

HeartRhythm Case Rep 2020 May 1;6(5):241-243. Epub 2020 Apr 1.

Department of Cardiology, Division of Electrophysiology, North Shore University Hospital, Northwell Health, Manhasset, New York.

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http://dx.doi.org/10.1016/j.hrcr.2020.03.017DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7194904PMC
May 2020

Effect of Chloroquine, Hydroxychloroquine, and Azithromycin on the Corrected QT Interval in Patients With SARS-CoV-2 Infection.

Circ Arrhythm Electrophysiol 2020 06 29;13(6):e008662. Epub 2020 Apr 29.

Division of Electrophysiology, Department of Cardiology, North Shore University Hospital, Northwell Health, Manhasset, NY (M.S., J.G., D.C., B.S.K., A.M., E.M., P.M., J.W., S.B., R.M., R.J., L.M.E.).

Background: The novel SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) is responsible for the global coronavirus disease 2019 pandemic. Small studies have shown a potential benefit of chloroquine/hydroxychloroquine±azithromycin for the treatment of coronavirus disease 2019. Use of these medications alone, or in combination, can lead to a prolongation of the QT interval, possibly increasing the risk of Torsade de pointes and sudden cardiac death.

Methods: Hospitalized patients treated with chloroquine/hydroxychloroquine±azithromycin from March 1 to the 23 at 3 hospitals within the Northwell Health system were included in this prospective, observational study. Serial assessments of the QT interval were performed. The primary outcome was QT prolongation resulting in Torsade de pointes. Secondary outcomes included QT prolongation, the need to prematurely discontinue any of the medications due to QT prolongation, and arrhythmogenic death.

Results: Two hundred one patients were treated for coronavirus disease 2019 with chloroquine/hydroxychloroquine. Ten patients (5.0%) received chloroquine, 191 (95.0%) received hydroxychloroquine, and 119 (59.2%) also received azithromycin. The primary outcome of torsade de pointes was not observed in the entire population. Baseline corrected QT interval intervals did not differ between patients treated with chloroquine/hydroxychloroquine (monotherapy group) versus those treated with combination group (chloroquine/hydroxychloroquine and azithromycin; 440.6±24.9 versus 439.9±24.7 ms, =0.834). The maximum corrected QT interval during treatment was significantly longer in the combination group versus the monotherapy group (470.4±45.0 ms versus 453.3±37.0 ms, =0.004). Seven patients (3.5%) required discontinuation of these medications due to corrected QT interval prolongation. No arrhythmogenic deaths were reported.

Conclusions: In the largest reported cohort of coronavirus disease 2019 patients to date treated with chloroquine/hydroxychloroquine±azithromycin, no instances of Torsade de pointes, or arrhythmogenic death were reported. Although use of these medications resulted in QT prolongation, clinicians seldomly needed to discontinue therapy. Further study of the need for QT interval monitoring is needed before final recommendations can be made.
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http://dx.doi.org/10.1161/CIRCEP.120.008662DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7299095PMC
June 2020

COVID-19 Infection Unmasking Brugada Syndrome.

HeartRhythm Case Rep 2020 May 25;6(5):237-240. Epub 2020 Mar 25.

Department of Cardiology, Division of Electrophysiology, North Shore University Hospital, Northwell Health, Manhasset, New York.

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http://dx.doi.org/10.1016/j.hrcr.2020.03.012DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7138191PMC
May 2020

Non-invasive electroanatomic mapping to reduce mapping time during catheter ablation of outflow tract ventricular premature depolarizations.

J Interv Card Electrophysiol 2021 Mar 13;60(2):295-302. Epub 2020 Apr 13.

Department of Cardiac Electrophysiology, Northwell Health-Lenox Hill Heart and Lung, 100 East 77th Street, New York, NY, 10075, USA.

Purpose: Ventricular premature depolarizations (VPD) commonly arise from the septal anterior right ventricular outflow tract (sRVOT), the left coronary cusp (LCC), and the distal great cardiac vein (dGCV), and share common ECG characteristics. To assess the diagnostic accuracy of non-invasive electroanatomic mapping (NIEAM) in differentiating VPD origin between sRVOT, LCC and dGCV and quantify its clinical utility in eliminating unnecessary mapping and ablation.

Methods: ECGs and NIEAMs (CardioInsight, Medtronic) from 32 patients (56.3 ± 15.2 years) undergoing ablation for VPDs originating from sRVOT, LCC, or dGCV were blindly reviewed for their diagnostic accuracy in predicting the SOO. A 2-step algorithm using NIEAM-based activation timing of the superior basal septum of < 22.5 ms and lateral mitral annulus of > 60.5 ms was compared with subjective ECG evaluation, the maximum deflection index (MDI), and the V transitional ratio in predicting SOO. We calculated the mapping and ablation time that could have been avoided had the operators relied on activation timing by NIEAM in designing their mapping and ablation strategy.

Results: NIEAM was superior to subjective ECG evaluation, MDI, and V transition ratio in predicting the SOO yielding a sensitivity and specificity of 96.9% and 98.4% respectively. Using NIEAM in determining the SOO would have obviated 22 ± 4.5 min of mapping in the wrong chamber and prevented unnecessary ablation of 4.5 ± 1.8 min.

Conclusion: NIEAM has high diagnostic accuracy in differentiating between sRVOT, LCC, and dGCV VPDs, and can significantly reduce mapping time, obviating the need for unnecessary access and ablation.
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http://dx.doi.org/10.1007/s10840-020-00731-zDOI Listing
March 2021

Understanding myocardial infarction.

F1000Res 2018 3;7. Epub 2018 Sep 3.

Division of Cardiology, Department of Internal Medicine, University of California San Francisco-Fresno, 2335 E. Kashian Lane, Suite 460, Fresno, CA 97301, USA.

Over the last 40 years, our understanding of the pathogenesis of myocardial infarction has evolved and allowed new treatment strategies that have greatly improved survival. Over the years, there has been a radical shift in therapy from passive healing of the infarction through weeks of bed rest to early discharge usually within 2 to 3 days as a result of immediate reperfusion strategies and other guideline-directed medical therapies. Nevertheless, challenges remain. Patients who develop cardiogenic shock still face a high 30-day mortality of at least 40%. Perhaps even more important is how do we identify and prevent patients from developing myocardial infarction in the first place? This article discusses these milestones of therapy and considers important issues for progress in the future.
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http://dx.doi.org/10.12688/f1000research.15096.1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6124376PMC
July 2019

Initial Surgery in Tailoring Treatment for Children With Stage II and III Wilms' Tumor: An Experience From Resource Challenged Settings.

World J Oncol 2015 Oct 26;6(5):441-445. Epub 2015 Oct 26.

Department of Surgery, College of Medicine, King Faisal University, Al Ahsa, KSA.

Background: Although Wilms' tumor (WT) is ranked first among primary childhood's renal neoplasm, controversy still exists regarding the best approach for its management. The study aimed at evaluating the role of initial surgery in treatment of stage II and III pediatric WT as a part of the short administration schedule as in National Wilms' Tumor Study (NWTS)-4 and evaluating its effectiveness compared to the long administration schedule.

Methods: The study included 30 children who were primarily diagnosed as stage II and III WT. They were divided into two equal groups. Group I (n = 15) included those children who had undergone neoadjuvant chemotherapy followed by surgery and postoperative chemotherapy, while group II (n = 15) included those children who had undergone primary surgery as an initial management followed by chemotherapy. After a mean postoperative follow-up period of 14 ± 5 months, clinical and radiological evaluation was performed to all patients.

Results: In group I, 10 patients were preoperatively diagnosed as stage II and five patients as stage III while in group II, 11 patients were proved to be stage II and four patients were stage III. After a follow-up period, clinical and radiological evaluation using CT was performed to all patients. In patients with stage II, evidence of recurrence was noted in three patients of group I whereas no patient showed any evidence of recurrence in group II. In patients with stage III, rebound increase in size was seen in two patients in group I and only one patient in group II.

Conclusions: Initial surgical intervention with appropriate adjuvant therapy has better outcomes than the neoadjuvant chemotherapy and delayed surgery for children primarily diagnosed as stage II and III WT. Moreover, it may act as a short administration schedule for the treatment as it is not less effective than the long administration schedule and can be administered at a substantially lower total treatment cost.
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http://dx.doi.org/10.14740/wjon876wDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5624669PMC
October 2015

Atomically precise bottom-up fabrication of graphene nanoribbons.

Nature 2010 Jul;466(7305):470-3

Empa, Swiss Federal Laboratories for Materials Science and Technology, Thun and 8600 Dübendorf, Switzerland.

Graphene nanoribbons-narrow and straight-edged stripes of graphene, or single-layer graphite-are predicted to exhibit electronic properties that make them attractive for the fabrication of nanoscale electronic devices. In particular, although the two-dimensional parent material graphene exhibits semimetallic behaviour, quantum confinement and edge effects should render all graphene nanoribbons with widths smaller than 10 nm semiconducting. But exploring the potential of graphene nanoribbons is hampered by their limited availability: although they have been made using chemical, sonochemical and lithographic methods as well as through the unzipping of carbon nanotubes, the reliable production of graphene nanoribbons smaller than 10 nm with chemical precision remains a significant challenge. Here we report a simple method for the production of atomically precise graphene nanoribbons of different topologies and widths, which uses surface-assisted coupling of molecular precursors into linear polyphenylenes and their subsequent cyclodehydrogenation. The topology, width and edge periphery of the graphene nanoribbon products are defined by the structure of the precursor monomers, which can be designed to give access to a wide range of different graphene nanoribbons. We expect that our bottom-up approach to the atomically precise fabrication of graphene nanoribbons will finally enable detailed experimental investigations of the properties of this exciting class of materials. It should even provide a route to graphene nanoribbon structures with engineered chemical and electronic properties, including the theoretically predicted intraribbon quantum dots, superlattice structures and magnetic devices based on specific graphene nanoribbon edge states.
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http://dx.doi.org/10.1038/nature09211DOI Listing
July 2010

Conjugated Triphenylene Polymers for Blue OLED Devices.

Macromol Rapid Commun 2009 Jul 3;30(14):1279-83. Epub 2009 Jul 3.

Max-Planck-Institute for Polymer Research, Ackermannweg 10, D-55128 Mainz, Germany.

Three polytriphenylene derivatives with phenyl and alkyl groups as side chains have been tested as blue light emitters. The best performance in terms of turn-on voltage and luminance efficiencies was obtained for poly(2-heptyl-3-(4-octylphenyl)-1,4-diphenyl-6,11-triphenylenyl-1,4-benzene) (1), which was additionally blended with an electron-transporting and a hole-injection material in the device, and had an onset of 4.6 V and reached 0.73 cd · A(-1) .
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http://dx.doi.org/10.1002/marc.200900332DOI Listing
July 2009
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