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Background: Left bundle branch block (LBBB) may occur with or without structural heart disease. In patients with coronary artery disease the presence of LBBB is associated with an increased risk of cardiovascular events.Methods and Results: This study examined the outcome of 293 medically treated patients with LBBB and symptoms who were undergoing stress thallium-201 single photon emission computed tomography imaging. One hundred seventy-three men and 120 women with an age range of 67 +/- 9 years and a pretest probability of coronary artery disease of 77% +/- 28% were studied. During a mean follow-up of 33 months 58 hard cardiac events (death or nonfatal myocardial infarction) and 112 total events (hard events, coronary angioplasty, coronary bypass surgery, or cardiac transplantation) occurred. Univariate and multivariate Cox survival analysis with clinical, stress, hemodynamic, and single photon emission computed tomography variables identified the perfusion defect size (chi square = 27, p = 0.0001) and increased lung thallium uptake as the most important independent predictors of hard or total cardiac events. The hard event-free survival rate was 91% in patients with no or small defects (<15% of left ventricular myocardium) and 72% in patients with large defects (p = 0.0001, RR = 3.2, 95% CI 1.7 to 5.9). The total event-free survival rate was 81% in patients with small defects and 48% in patients with large defects (p = 0.0001, RR = 2.7, 95% CI 1.9 to 4.0). The total event rate was 54% in patients with large perfusion defects and increased lung uptake and 17% in patients with no or small abnormality and normal lung thallium uptake (p = 0.0001).Conclusion: Single photon emission computed tomography perfusion imaging is useful in predicting outcome in patients with LBBB and intermediate pretest probability of coronary artery disease. The size of perfusion abnormality and lung thallium uptake stratified patients into high and low risk groups with a threefold difference in hard and total cardiac events. [ABSTRACT FROM AUTHOR]

Background: The lack of health education resources specific to people with disabilities contributes to disparities in outcomes. Developing user-centered materials with representative images tailored to people with disabilities could help improve knowledge and outcomes., Objective: As a first step in developing an online sexual health resource for adolescents with physical disabilities, we sought end-user feedback to create illustrated characters for use in educational materials., Methods: Two styles of characters were developed by the research team, which included a professional disability artist. Verbal and online survey feedback was obtained at the Spina Bifida Association's Clinical Care Conference. A new image was created incorporating initial feedback. The new image and favored image from the first round were then tested through an online survey advertised on the Spina Bifida Association's Instagram story feed. Open-ended comments were organized by categories and overlapping themes., Results: Feedback was obtained from 139 audience members and 25 survey respondents from the conference and 156 Instagram survey respondents. Themes included depiction of disability, nondisability diversity, other physical appearance, emotional response, and design style. Most frequently, participants suggested the inclusion of characters with a range of accurately depicted mobility aids and of characters without mobility aids. Participants also wanted a larger, more diverse group of happy, strong people of all ages., Conclusions: This work culminated in the codevelopment of an illustration that represents how people impacted by spina bifida view themselves and their community. We anticipate that using these images in educational materials will improve their acceptance and effectiveness., (Copyright © 2023 Elsevier Inc. All rights reserved.)

In present investigation, we developed paclitaxel (PTX)-loaded adenosine (ADN)-conjugated PLGA nanoparticles for combating triple-negative breast cancer (TNBC), where ADN acts as a substrate for adenosine receptors (AR) that are overexpressed in TNBC. Using synthesized PLGA-PEG-ADN, PTX-loaded nanoparticles (PTX ADN-PEG-PLGA NPs) were prepared via emulsion diffusion evaporation process that rendered particles of size 135 ± 12 nm, PDI of 0.119 ± 0.03, and entrapment-efficiency of 79.26 ± 2.52%. The NPs showed higher %cumulative release at pH 5.5 over 7.4 with Higuchi release kinetics. The PTX ADN-PEG-PLGA NPs showed ~ 4.87- and 5.22-fold decrease in %hemolysis in comparison to free PTX and Intaxel ® , indicating their hemocompatible nature. The ADN modification assisted cytoplasmic internalization of particles via AR-mediated endocytosis that resulted in ~ 3.77- and 3.51-fold reduction in IC 50 and showed apoptosis index of 0.93 and 1.18 in MDA-MB-231 and 4T1 cells respectively. The pharmacokinetic profile of ADN-PEG-PLGA NPs revealed higher AUC and t1/2 than Intaxel ® and Nanoxel ®  pharmacodynamic activity showed ~ 18.90-fold lower %tumor burden than control. The kidney and liver function biomarkers showed insignificant change in the levels, when treated with PTX ADN-PEG-PLGA NPs and exhibited no histological alterations in the liver, spleen, and kidney. Overall, the optimized particles were found to be biocompatible with improved anti-TNBC activity., (© 2022. Controlled Release Society.)

Sildenafil (SLD) is employed for the management of erectile dysfunction and pulmonary arterial hypertension. It exhibits meagre water solubility and is available in the form of citrate salt hydrate to improve the solubility. However, it still exhibits moderate solubility, high first-pass metabolism, resulting in very less oral bioavailability. The present study demonstrates the preparation of self-nanoemulsifying drug delivery system for augmenting the oral bioavailability of SLD. Oleic acid and Capmul MCM C8 blend (oil phase), Cremophor ® RH40 (surfactant), and Labrafil ® M1944 CS (cosurfactant) were selected as main constituents for making liquid preconcentrate based on the solubility and emulsification study. The preconcentrate upon dilution and emulsification showed droplet size 52.03 ± 13.03 nm, PDI 0.143 ± 0.028, and % transmittance was 99.77 ± 1.86% with SLD load of 40 mg/g of formulation. The prepared formulation was further assessed for stability, in vitro release, Caco-2 cell uptake, and in vivo pharmacokinetic performance. SLD-SNEDDS formulation was found to be robust in terms of stability against several folds dilution in the gastrointestinal tract (GIT), freeze-thaw cycles, and had a storage stability of 3 months at 4 °C and 25 °C. SLD-SNEDDS showed ~4.7-fold and ~5-fold increase in time- and concentration-dependent cellular uptake as against SLD cultured with Caco-2 cells. In vivo pharmacokinetic study revealed ~5.8- and ~2.5-fold increase in AUC 0-∞ values in case of SLD-SNEDDS as against SLD suspension and SLD citrate solution, respectively., (© 2022. Controlled Release Society.)

Triple-negative breast cancer (TNBC) belongs to the category of the most destructive forms of breast cancer. Being a highly potent chemotherapeutic agent, paclitaxel (PTX) is extensively utilized in the management of various cancers. Commercially available PTX formulations contain non-targeted drug carriers that result in low antitumor activity because of non-specific tissue distribution. Thus, to resolve this issue, we designed PTX-loaded pH-sensitive liposomes (pH Lipos) in the present investigation and used adenosine (ADN) as a targeting ligand. Further, d-α-tocopheryl polyethylene glycol succinate (TPGS) was incorporated into the liposomes to impart a stealth effect to the system. For the development of these pH Lipos, different conjugates were synthesized (ADN-CHEMS and TPGS-ADN) and further utilized for the preparation of ADN-PEG-pH Lipo and ADN-pH Lipo by a thin-film hydration method. DOPE:HSPC:CHEMS:cholesterol at a molar ratio of 3:3:2:2 was selected for the preparation of pH-Lipo possessing 7.5% w/w drug loading. They showed a particle size below 140 nm, a PDI below 0.205, and a % EE greater than 60%. All of the pH Lipos displayed a biphasic pattern of PTX release at pH 7.4 and 5.5. However, the percent drug release at pH 5.5 was substantially greater because of the pH-sensitive nature of the liposomes. The MDA MB 231 and 4T1 cell lines depicted improvement in the qualitative as well as quantitative cellular uptake of PTX ADN-PEG-pH Lipo with a substantial decrease in the IC 50 value. Moreover, a higher apoptotic index was observed with pH Lipo compared to free PTX. PTX ADN-PEG-pH Lipo revealed a 3.98- and 3.41-fold rise in the AUC and t 1/2 values of PTX compared to Intaxel, respectively. Overall, characteristic decreases in tumor volume and serum toxicity marker levels were observed, which confirmed the development of an efficient and safe formulation.

The harvested plant products, specifically, the grains of cereals are major drivers of soil phosphorus (P) depletion. However, the breeding or biotechnology efforts to develop low P seeds have not been attempted because of possible adverse effects on seedling vigour and crop establishment. Several studies have contradictory observations on influence of seed P on seedling vigour. Lack of appropriate genetic material has been the major bottleneck in reaching the consensus. In this study, we used 30 EMS induced mutants of rice cultivar Nagina22 to understand the role of seed P on seedling vigour and associated physiological processes. Seedling vigour, morpho-physiological characteristics, acid phosphatases, alpha-amylase, and expression of P transporter genes were analyzed in seedlings obtained from seeds of high and low grain P mutants. The study suggests that seed P has a significant role on seedling vigour, chlorophyll content and photosynthesis process of young seedlings, and P transport from roots. Notably, we identified few mutants such as NH4791, NH4785, NH4714, NH4663, NH4614, and NH4618 which showed least influence of low seed P on seedling vigour and other metabolic processes. Therefore, these mutants can be used in breeding programs aiming for development of low P grains. Also, these and other identified mutants can be used to decipher the genetic and molecular mechanisms regulating the differential response of seed P on germination, seedling vigour and several other physiological processes influencing the crop growth and establishment., (© 2022. The Author(s).)

With the current COVID19 pandemic, we have to weigh human life, prosperity, and value, while implicitly acknowledging that controlling case spread and mortality is a challenge. Identifying COVID19-infected patients and disconnecting them to avoid COVID transmission is one of the most difficult tasks for clinicians. As a result, figuring out who infected with covid19 is crucial. COVID19 is identified using a 4-6-hour reverse transcription-polymerase chain reaction (RT-PCR). Another way to detect Coronavirus early in the disease process is by using chest X-rays (CXR).We extracted characteristics from chest X-ray images using VGG16 and ResNet50 deep learning algorithms, then classified them into three groups: viral pneumonia, normal, and COVID19. We ran 15,153 images through the models to see how accurate they were in real-world situations. For detecting COVID19 cases, the VGG16 model has an average accuracy of 89.34 %, whereas ResNet50 has an accuracy of 91.39 %. When utilizing deep learning to identify COVID19, however, a larger dataset is necessary. It has the desired effect of detecting situations accurately., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the scientific committee of the International Conference on Advanced Materials for Innovation and Sustainability.)

Combination therapy, which combines anti-cancer drugs with different oligonucleotides, have shown potential in cancer treatment. However, delivering a hydrophobic anti-cancer drug and a hydrophilic oligonucleotide simultaneously is a herculean task. This study takes advantage of interactions between histidine-lauric acid-based green surfactant and poly(amidoamine) dendrimers to achieve this aim. The green surfactant was synthesized by carbodiimide chemistry and characterized by FTIR, 1 H-NMR, and mass spectroscopy. Further, green surfactant-dendrimer aggregates encapsulating DTX and complexing SIRT 1 shRNA i.e., "aggreplexes" were developed and characterized. The term "aggreplexes" signifies complexes which are formed between green-surfactant-dendrimer aggregates and SIRT-1 shRNA via electrostatic interaction. The aggreplexes displayed particle size of 262.33 ± 3.87 nm, PDI of 0.25 and entrapment efficiency of 70.56 %. The TEM images revealed spherical shape of aggreplexes with irregular outer surface and corroborated particle size obtained from zetasizer. The in-vitro release study revealed biphasic release patterns of DTX from aggreplexes and were compatible for intravenous administration. Further, aggreplexes augmented cellular uptake in MDA-MB-231 cells by ∼1.87-fold compared to free DTX. Also, EGFP expression revealed significantly higher transfection of aggreplexes compared to naked shRNA and Superfect™ complexes. Further, aggreplexes showed higher cytotoxicity in MDA-MB-231 cells and ∼4.16-fold reduction in IC 50 value compared to free DTX. Finally, apoptosis-index observed in case of aggreplexes was ∼3.57-fold higher than free DTX. These novel aggreplexes showed increased drug loading capacity and superior gene transfection potential. Thus, they open new avenues for co-delivery of hydrophobic anti-cancer drugs and hydrophilic therapeutic genes for improving current standards of cancer therapy., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Background: Historically, pulmonary hypertension (PH) has been considered as one of the contraindications for lung volume reduction surgery (LVRS). Newer studies have shown that LVRS is successful in select emphysema patients with PH., Methods: In-hospital and 1-year functional and quality of life (QOL) outcomes were studied in patients with PH post-LVRS. PH was defined as pulmonary artery pressure (PAP) exceeding 35 mm Hg by right heart catheterization (RHC), where available, or else exceeding 35 mm Hg by echocardiogram., Results: Of 124 patients who underwent LVRS, 56 (45%) had PH (mean PAP, 41 mm Hg) with 48 mild to moderate and 8 severe PH. In-hospital outcomes were similar between patients with and without PH: hours of artificial ventilation (1.8 vs 0.06, P = .882), days in intensive care (4 vs 6, P = .263), prolonged air leak (12% vs 19%, P = .402), and days of hospital stay (13 vs 16, P = .072). Lung function improved significantly at the 1-year follow-up in patients with PH: forced expiratory volume in 1 second % predicted (26 vs 38, P = .001), forced vital capacity % (62 vs 90, P = .001), residual volume % predicted (224 vs 174, P = .001), diffusion capacity of the lung for carbon monoxide % predicted (36 vs 43, P = .001), 6-minute walk distance test (1104 vs 1232 feet, P = .001), and QOL utility scores (0.67 vs 0.77, P = .001). There were no differences in in-hospital, baseline, and follow-up functional and QOL outcomes between patients with and without PH., Conclusions: In this small, single-institution cohort, outcomes of patients undergoing LVRS for emphysema with PH were similar to those of patients without PH. LVRS may be a potential option for select emphysema patients with PH., (Copyright © 2020 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Among many, the oral route of delivery is considered to be the most favorable route with the highest patient compliance. The main issue with oral delivery is the environmental vulnerability of gastro intestinal tract (G.I.T). The bioavailability could further decrease when drug has poor aqueous solubility and permeability through biological membrane. This drawback could be resolved by employing drug-phospholipid complex strategy, as they utilize mechanism which is similar to the absorption mechanism of nutritional constituents form G.I.T. The drug-phospholipid complexes are considered ideal for oral delivery as they are biodegradable and non-toxic, which enable them to be employed as solubilizer, emulsifier, and as a matrix forming excipient for dugs with poor solubility and/or permeability. The present review compiles the basic know how about the phospholipids and the mechanism through which it improves the bioavailability of drugs. Further, it also compiles the crucial formulation aspects and methods of preparations of drug-phospholipid complex along with its physical and in silico characterization techniques. The increase in number of recent reports involving the utilization of drug-phospholipid complex to improve oral bioavailability of drugs thus explains how vital the strategy is for a successful oral delivery.

Physical characterization of solid form of drug is of paramount importance as its biopharmaceutical properties and/or its processing behavior may be altered. Early identification and monitoring of solid state transformation is a critical requirement for pharmaceutical product development. In combination with chemometrics, a non destructive and non invasive technique like NIR is a powerful tool for solid state characterization. Main focus of this review is application of NIR for qualitative and quantitative analysis of solid forms of drugs and excipients. In addition, this review also sheds light on recent advancement in NIR, such as NIR chemical imaging and NIR based hyphenated techniques., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Maxillofacial surgery, like any other surgical specialty is greatly dependent on the discipline of radiology. This poses a greater challenge because of the complex anatomy of this region. Various investigation modalities have been applied in diagnosing various diseases which are found in the maxillofacial region, including IOPA, PET, USG, CT, MRI and panoramic radiographs. Of these, USG can easily diagnose non invasive and soft tissue diseases. It is very useful in diagnosing the diseases which are not usually evident on a conventional radiograph. However; many of the dentists are not aware of the benefits of USG in diagnosis of oral diseases. In this article, the use of ultrasound in diagnosing the various pathologies of maxillofacial region is elaborated.

Background: Stress cardiomyopathy (SCM) is a newly described reversible cardiomyopathy of largely unclear etiology. We studied SCM in a large cohort to gain further insights., Methods: We retrospectively identified 114 cases of SCM from among 12,150 consecutive North American patients diagnosed as Troponin-positive acute coronary syndrome, from January 2000 through December 2007, at two 24-h coronary angioplasty-capable centers. Left ventriculographic wall contractility was analyzed and scored in 107 patients on the right anterior oblique view., Results: In 107 patients (66+/-14 years, 99 females), variable regional contractility or "ballooning" was observed including: postero-basal, 1%; basal+mid-ventricular, 1%; diaphragmatic, 2%; localized apical, 2%; antero-lateral, 11%; complete mid-ventricular, 29%; and classical variant, 54%. The localized and complete mid-ventricular variants (n=45, 40 females) had a younger median age at presentation (64 vs. 71 years, p=0.008) and higher median LV ejection fraction (45% vs. 35%, p=0.006) than the classical or tako-tsubo variants (n=58, 55 females) with similar baseline exposure to stressors, risk factor and in-hospital complications. Frequency of involvement and mean contractile score (dysfunction) of the antero-lateral segment was significantly (p<0.05) greater in the order, antero-lateral>diaphragmatic>apical>basal., Conclusion: From a single large cohort of SCM, evidence on significant individual variation in clinical and morphological pattern was confirmed. Frequency and vulnerability to transient dysfunction differs within segments with antero-lateral involvement significantly greater than diaphragmatic, apical, basal-anterior and basal-posterior LV segments. Further studies in phenotype should be undertaken for proper identification, classification and pathophysiological implications., (Copyright (c) 2008 Elsevier Ireland Ltd. All rights reserved.)

Objectives: To evaluate predictor variables and accuracy of left atrial appendage (LAA) filling defects seen on multidetector computed tomographic (MDCT) scan in predicting LAA thrombus in patients undergoing pulmonary vein (PV) isolation procedure., Methods: Electrocardiogram-gated 64-slice MDCT and transesophageal echocardiography (TEE) were undertaken in 51 consecutive patients with nonvalvular atrial fibrillation who were referred for circumferential antral pulmonary vein isolation., Results: In 51 patients (37 men; mean age, 64 years), left atrium (LA) diameter emerged as the predictor of LAA filling defects (odds ratio, 4.9; 95% confidence interval, 1.19-20.25). Left atrial appendage filling defects had sensitivity of 100%, specificity of 95.92%, positive predictive value of 0.5, and negative predictive value of 1, for thrombi seen on TEE image. A mean LAA/ascending aorta Hounsfield unit ratio of 0.78 or less was identified as a sensitive predictor of thrombus on TEE (sensitivity, 100%; specificity, 87.8%; positive predictive value, 0.25; and negative predictive value, 1)., Conclusions: A larger LA predisposes to LAA filling defects on MDCT scan. Pending prospective validation, absence of LAA filling defects on 64-slice MDCT may reliably exclude LAA thrombi in patients with nonvalvular atrial fibrillation obviating the need for TEE.

Styrene monooxygenase (SMO) from Pseudomonas putida S12 is a two-component flavoenzyme composed of the NADH-specific flavin reductase, SMOB, and FAD-specific styrene epoxidase, SMOA. Here, we report the cloning, and expression of native and histidine-tagged versions of SMOA and SMOB and studies of the flavin transfer and styrene oxygenation reactions. In the reductive half-reaction, SMOB catalyzes the two-electron reduction of FAD with a turnover number of 3200 s(-1). Single turnover studies of the reaction of reduced SMOA with substrates indicate the formation of a stable oxygen intermediate with the absorbance characteristics of a flavin hydroperoxide. Based on the results of numerical simulations of the steady-state mechanism of SMO, we find that the observed coupling of NADH and styrene oxidation can be best explained by a model, which includes both the direct transfer and passive diffusion of reduced FAD from SMOB to SMOA.

Chemical investigation of a soft coral species of the genus Lobophytum has resulted in the isolation of three new sphingolipids--(2S,3S,4R)-2-nonadecanoylamino-octadecane-1,3,4-triol (1), (2S,3R,4E,8E)-[(2'R)-2'-hydroxyheptadecanoylamino]-4,8-octadecadiene-1,3-diol (2), 1-O-(beta-D-glucopyranosyl)-(2S,3R,4E,8E)-2-[(2'R)-2'-hydroxynonadecanoylamino]-9-methyl-4,8-octadecadiene-1,3-diol (3) and a sterol--(24S)-ergost-5-en-3beta,7beta-diol (4) along with the known sphingolipid--(2S,3R,4E,8E)-2-hexadecanoylamino-4,8-octadecadien-1,3-diol (5) which showed cytotoxicity against human peripheral blood mononuclear cells (PBMC).

Chemical examination of the marine sponge Iotrochota baculifera of the Indian Ocean furnished a sphingolipid (1), a new glycosphingolipid (iotroridoside-B, 2) and a four-component mixture of sphingolipids (3a-d) with two new components. Structure elucidation was carried out by spectral and chemical methods.

Previous studies have examined the predictors of outcome in medically treated patients with coronary artery disease (CAD). There is limited information on predictors of outcome after coronary artery bypass grafting (CABG). This study examined the predictors of outcome of 255 patients with CAD, at a mean time of 5 years after CABG for angina pectoris. The 255 patients underwent coronary angiography and stress single-photon emission computed tomography (SPECT) myocardial perfusion imaging after CABG. During a mean follow-up of 41 +/- 28 months after stress testing, there were 34 hard events (24 cardiac deaths and 10 nonfatal myocardial infarctions). The hemodynamics during stress testing, and age and gender were not predictors of events. The SPECT variables of multivessel perfusion abnormality, perfusion deficit size, and increased lung thallium uptake were predictors of death and total events by uni- and multivariate survival analysis. There were 14 events in 45 patients (31%) with multivessel abnormality and increased lung thallium uptake, 14 events in 101 patients (14%) with either multivessel abnormality or increased lung uptake, and 6 events in 109 patients (6%) with neither of these 2 variables (p = 0.0001). The annual mortality and total event rates were 7.5% and 9.5% with both variables, 3.4% and 4.3% with either variable, and 0.6% and 1.7% with neither of the variables (p = 0.01). Thus, stress SPECT perfusion imaging is useful to stratify patients after CABG into low, intermediate, and high risk groups for future cardiac events.

The influence of the clinical presentation on the long-term outcome in 213 consecutive patients with ICDs, ECG storage capability, and nonthoracotomy leads, was analyzed. Sixty-six patients presented with cardiac arrest (CA), 81 patients with hemodynamically stable VT, and 66 patients with syncope (SY). Patient characteristics were: mean age CA 62, VT 61, SY 61 years; mean ejection fraction CA 31%, VT 29%, SY 30%; coronary artery disease CA 71%, VT 71%, SY 64% (all P > 0.05 Fisher's exact test); female gender CA 40%, VT 14%, SY 19% (CA vs VT and SY, P < 0.005); inducibility by programmed stimulation CA 50%, VT 84%, SY 61% (VT vs CA and SY, P < 0.001, CA vs SY, P > 0.05). During a mean follow-up of 14.5 months, 29 patients died: CA 12%, VT 14%, SY 9% (P > 0.05). Comparing Kaplan-Meier curves, no difference in the time course of overall mortality was found (log-rank P > 0.05). In the CA, VT, and SY groups, 543, 1,630, and 189 ICD therapies (including antitachycardia pacing, low energy cardioversion, and defibrillation) were observed, respectively. Actuarial analysis showed a shorter interval between implantation and first ICD therapy for VT versus CA and SY (log-rank P < 0.005). Patients presenting with VT experienced earlier and more frequent ICD therapies than patients with CA or SY independent of age, ejection fraction, and heart disease. No difference in overall mortality and time course of fatal events was observed among the three groups.

Objectives: This study sought to document postoperative complications attributable to nonthoracotomy defibrillation lead systems in a large cohort., Background: The incidence of postoperative complications specifically associated with nonthoracotomy defibrillation lead systems is unknown., Methods: Postoperative lead-related complications were evaluated in 170 patients with a nonthoracotomy defibrillation lead system who were followed up for a mean (+/- SD) of 17 +/- 12 months. Each system incorporated one or more intravascular leads. In 117 patients (69%), the system incorporated a subcutaneous defibrillation patch. All implantations were performed in an operating room by cardiothoracic surgeons. Defibrillation thresholds were measured at implantation, before hospital discharge (mean 3 +/- 2 days) and at 4 to 18 weeks after implantation. Patients were evaluated every 2 to 3 months after implantation or as indicated by clinical exigency., Results: Twenty-seven patients (15.9%) were diagnosed with a lead-related complication that either extended the initial hospital period or led to a second hospital admission. Complications included endocardial lead or subcutaneous defibrillation patch dislodgment in eight patients (4.7%), which was diagnosed between 2 and 345 days after implantation; endocardial or subcutaneous patch lead fracture in six (3.5%), which was diagnosed between 53 and 600 days after implantation; subcutaneous patch mesh fracture in one, which was diagnosed at 150 days after implantation; subclavian vein thrombosis in three (1.8%), which was diagnosed at 2 to 50 days after implantation; and unacceptably elevated defibrillation threshold (within 5 J of maximal device output) in nine (5.3%), which was documented at one of the two postimplantation evaluations in eight patients or at the time of failure to terminate a spontaneous ventricular tachycardia in one. Seventeen of the 27 patients required reoperation for correction of their complication. In addition, system infection requiring complete explantation occurred in seven other patients (4.1%) at an interval from implantation ranging from 14 to 120 days., Conclusions: Postoperative complications related to a nonthoracotomy defibrillation lead system were common and frequently required reoperation for correction. The rate of system explantation due to infection was also significant. Postoperative defibrillation testing and vigilant outpatient follow-up evaluation are necessary to ensure normal lead function.

Objectives: This study compared the diagnostic accuracy of exercise thallium-201 single-photon emission computed tomography (SPECT) with the exercise electrocardiographic (ECG) response in patients with normal baseline ECG results., Background: Previous studies comparing exercise thallium imaging with exercise electrocardiography have included patients with abnormal rest ECG results that may have biased the results in favor of thallium imaging., Methods: Of 321 patients with a pretest likelihood of coronary artery disease of 70 +/- 29% (mean +/- SD) who underwent exercise stress testing and coronary angiography, 68 had no coronary artery disease; 94 had one-vessel disease; 79 had two-vessel disease; and 80 had three-vessel or left main coronary artery disease., Results: The diagnostic accuracy of SPECT was higher than that of the ECG response (79% vs. 49%, p < 0.0001). Patients with extensive (left main or three-vessel) coronary artery disease were older and had a lower work load, lower heart rate, greater ST segment depression and more extensive perfusion abnormalities than patients with no disease or one- or two-vessel disease. Multivariate discriminant analysis of exercise and thallium variables identified multivessel thallium abnormalities (F = 35), exercise heart rate (F = 18) and extent of ST segment depression (F = 6) as independent predictors of extensive disease. Of the 80 patients with left main or three-vessel disease, 37 (46%) had > or = 2-mm ST segment depression, 44 (55%) had multivessel SPECT abnormalities, and 61 (76%) had either > or = 2-mm ST depression or multivessel SPECT abnormalities (p = 0.0005 vs. the ECG response; p = 0.01 vs. SPECT)., Conclusions: In patients with an intermediate to high pretest probability of coronary artery disease and normal baseline ECG results, SPECT is superior to the ECG response in detecting coronary disease. Further, SPECT provides incremental power in identifying patients with extensive (left main or three-vessel) coronary disease.

Experimentally, heparin inhibits mechanisms that promote fibrosis, neointimal cellular proliferation, and thrombin bound to fibrin at the surface of intraluminal thrombus, but only in relatively high concentrations. A preliminary hypothesis was tested and confirmed in vitro that initial binding of 3H-heparin to mechanically injured porcine aorta is concentration-dependent over a 1,000-50,000 units/ml range (r = 0.9). The hypothesis was then tested in vitro that thermal exposure during contact of heparin to arterial tissue and to clot would enhance binding of the drug. 3H-heparin binding to clot, whole blood particulates, and washed erythrocytes was markedly enhanced by exposure to temperatures > 70 degrees C. Thermal exposure (80 degrees C x 40 s) also enhanced tissue persistence of the drug within porcine aorta subjected to a shear rate of 1,100(-1) in an annular Baumgartner chamber perfused with normal saline at 37 degrees C for 48 h. Heparin in vitro anticoagulant activity persisted after thermal exposure and binding to tissues. A new method was developed for local application of a heparin film that provides a maximum concentration with a tolerable systemic dose during an angioplasty procedure. In an in vivo rabbit model of mural fibrosis after iliac artery angioplasty, the 1-month mean angiographic luminal diameter loss (23% compared to the acute postangioplasty result by computer image analysis) in response to conventional balloon angioplasty (BA) and laser balloon angioplasty (LBA) was the same (P > 0.05). Local application of a heparin film (3,000 units at a concentration > 100,000 units/g), however, reduced the mean % loss in diameter 1 month after LBA (12%), but not after BA (29%), compared to arteries subjected to angioplasty without local heparin (P < .05). The results are consistent with the hypothesis that thermal energy enhances heparin binding to tissues and that local application of a heparin film favorably modulates arterial luminal responses to LBA, but not to BA, in this animal model.