Prognostic performance of the IABP-SHOCK II Risk Score among cardiogenic shock subtypes in the critical care cardiology trials network registry.

BACKGROUND: Risk stratification has potential to guide triage and decision-making in cardiogenic shock (CS). We assessed the prognostic performance of the IABP-SHOCK II score, derived in Europe for acute myocardial infarct-related CS (AMI-CS), in a contemporary North American cohort, including different CS phenotypes. METHODS: The critical care cardiology trials network (CCCTN) coordinated by the TIMI study group is a multicenter network of cardiac intensive care units (CICU). Participating centers annually contribute ≥2 months of consecutive medical CICU admissions. The IABP-SHOCK II risk score includes age > 73 years, prior stroke, admission glucose > 191 mg/dl, creatinine > 1.5 mg/dl, lactate > 5 mmol/l, and post-PCI TIMI flow grade < 3. We assessed the risk score across various CS etiologies. RESULTS: Of 17,852 medical CICU admissions 5,340 patients across 35 sites were admitted with CS. In patients with AMI-CS (n = 912), the IABP-SHOCK II score predicted a >3-fold gradient in in-hospital mortality (low risk = 26.5%, intermediate risk = 52.2%, high risk = 77.5%, P < .0001; c-statistic = 0.67; Hosmer-Lemeshow P = .79). The score showed a similar gradient of in-hospital mortality in patients with non-AMI-related CS (n = 2,517, P < .0001) and mixed shock (n = 923, P < .001), as well as in left ventricular (<0.0001), right ventricular (P = .0163) or biventricular (<0.0001) CS. The correlation between the IABP-SHOCK II score and SOFA was moderate (r2 = 0.17) and the IABP-SHOCK II score revealed a significant risk gradient within each SCAI stage. CONCLUSIONS: In an unselected international multicenter registry of patients admitted with CS, the IABP- SHOCK II score only moderately predicted in-hospital mortality in a broad population of CS regardless of etiology or irrespective of right, left, or bi-ventricular involvement.

Missed Opportunities in Identifying Cardiomyopathy Aetiology Prior to Advanced Heart Failure Therapy.

BACKGROUND: Specific aetiologies of cardiomyopathy can significantly impact treatment options as well as appropriateness and prioritisation for advanced heart failure therapies such as ventricular assist device (VAD) or orthotopic heart transplantation (OHT). We reviewed the tissue diagnoses of patients who underwent advanced therapies for heart failure (HF) to identify diagnostic discrepancies. METHODS: This study presents a retrospective cohort of the aetiology of cardiomyopathy in 118 patients receiving either durable VAD or OHT. Discrepancies between the preoperative aetiological diagnosis of cardiomyopathy with the pathological diagnosis were recorded. Echocardiographic and haemodynamic data were reviewed to examine differences in patients with differing aetiological diagnoses. RESULTS: Twelve (12) of 118 (12/118) (10.2%) had a pathological diagnosis that was discordant with pre-surgical diagnosis. The most common missed diagnoses were infiltrative cardiomyopathy (5) and hypertrophic cardiomyopathy (3). Patients with misidentified aetiology of cardiomyopathy had smaller left ventricular (LV) dimensions on echocardiography than patients with dilated cardiomyopathy (5.8±0.9 vs 6.7±1.1 respectively p=0.01). CONCLUSIONS: Most HF patients undergoing VAD and OHT had a correct diagnosis for their heart failure prior to treatment, but a missed diagnosis at time of intervention (VAD or OHT) was not uncommon. Smaller LV dimension on echocardiogram in a patient with a non-ischaemic cardiomyopathy warrants further workup for a more specific aetiology.

Predictive Performance of the International Takotsubo Registry Score in the Diagnosis of Takotsubo Syndrome Among Women with Non-ST Segment Elevation Myocardial Infarction.

Background: The International Takotsubo Registry (InterTAK) score was developed to assess the probability of takotsubo syndrome (TTS) and to distinguish it from acute coronary syndrome, which has a similar clinical presentation. A European Society of Cardiology (ESC) consensus statement suggests invasive coronary angiography may be deferred in patients with non-ST segment elevation myocardial infarction (NSTEMI) and high probability of TTS. We aimed to determine the predictive performance of the InterTAK score in a real-world population of NSTEMIs. Materials and Methods: The InterTAK score was retrospectively calculated for consecutive female patients with NSTEMI who underwent invasive coronary angiography at two academic medical centers in New York City from March 2016 to August 2018. Results: Among 375 women with NSTEMI, 15 (4%) had InterTAK score >70, indicating high probability of TTS. Ten (67%) met ESC TTS criteria for a noninvasive strategy, among whom seven had TTS, two had spontaneous coronary artery dissection (SCAD), and one had coronary artery disease requiring revascularization. A total of 48 women (13% of cohort) had a final diagnosis of TTS. The InterTAK score had an area under the receiver operating characteristics curve (AUC) of 0.82 (95% confidence interval, 0.75-0.88) for TTS, with 21% sensitivity and 98% specificity at score >70. Conclusions: In this real-world sample of consecutive female NSTEMI patients, the InterTAK score was predictive of TTS but a high score was rare, and use of the score to obviate invasive angiography could have resulted in delay of revascularization and missed diagnosis of SCAD for a small number of patients. The InterTAK score should be used in conjunction with other clinical variables for angiographic referral.

Mitral annular calcification in hypertrophic cardiomyopathy.

BACKGROUND: Changes in mitral valve anatomy contribute to left ventricular outflow tract obstruction (LVOTO) in hypertrophic cardiomyopathy (HCM). Mitral annular calcification (MAC) is common among patients with HCM but its implications are currently unknown. METHODS: We tested the hypothesis that echocardiographic MAC would be associated with anterior displacement of the mitral valve and LVOTO in a cohort of 304 patients with HCM aged ≥ 60 years (mean [SD] age 71.6 [7.7] years, 52% women). RESULTS: MAC was present in 141 (46%) patients. The mean (SD) MAC offset distance was 9.8 (4.8) mm. A higher proportion of those with MAC compared to those without MAC had SAM (84.2 vs. 63.8%, p < 0.001) and LVOTO (80.9 vs. 57.9%, p < 0.001). In patients with MAC, the septal-mitral valve distance was shorter compared to those without (19.4 [4.0] vs 21.5 [4.9] mm, p < 0.001). The mitral valve position ratio was greater in those with MAC compared to those without (1.00 [0.79, 1.22] vs. 0.86 [0.67, 1.05], p < 0.001) denoting greater anterior displacement, especially in those with MAC and LVOTO. After multivariable adjustment, MAC offset distance was associated with LVOTO (OR 1.16 [95% CI 1.07, 1.28] per mm, p = 0.001). Over a median follow-up of 2.7 years, 42 (29.8%) patients with MAC underwent surgery to relieve LVOTO, with no deaths. CONCLUSION: This study adds MAC to the known geometrical alterations of the mitral valve that predispose to LVOTO and suggests that surgical relief of LVOTO in the presence of MAC is safe when performed by an experienced surgeon.

Inflammatory Cardiomyopathy: Case-based Review on Clinical Presentation, Diagnosis, and Management.

Inflammatory cardiomyopathy is a broad term encompassing any disease leading to myocardial inflammation with associated cardiac dysfunction. While endomyocardial biopsy remains the gold standard for diagnosis, noninvasive imaging techniques, such as cardiac magnetic resonance imaging and positron emission tomography, have become powerful tools to facilitate the identification of underlying myocardial inflammation. This review presents a series of clinical cases with some common etiologies of inflammatory cardiomyopathy, including diagnosis and management.

Myocarditis in Relation to Angiographic Findings in Patients With Provisional Diagnoses of MINOCA.

OBJECTIVES: The aim of this study was to determine the prevalence of myocarditis among patients presenting with myocardial infarction with nonobstructive coronary arteries (MINOCA) in relation to the angiographic severity of nonobstructive coronary artery disease (CAD). BACKGROUND: MINOCA represents about 6% of all cases of acute myocardial infarction. Myocarditis is a diagnosis that may be identified by cardiac magnetic resonance (CMR) imaging in patients with a provisional diagnosis of MINOCA. METHODS: A systematic review was performed to identify studies reporting the results of CMR findings in MINOCA patients with nonobstructive CAD or normal coronary arteries. Study-level and individual patient data meta-analyses were performed using fixed- and random-effects methods. RESULTS: Twenty-seven papers were included, with 2,921 patients with MINOCA; CMR findings were reported in 2,866 (98.1%). Myocarditis prevalence was 34.5% (95% confidence interval [CI]: 27.2% to 42.2%) overall and was numerically higher in studies that defined MINOCA as myocardial infarction with angiographically normal coronary arteries compared with a definition that permitted nonobstructive CAD (45.9% vs. 32.3%; p = 0.16). In a meta-analysis of individual patient data from 9 of the 27 studies, the pooled prevalence of CMR-confirmed myocarditis was greater in patients with angiographically normal coronary arteries than in those with nonobstructive CAD (51% [95% CI: 47% to 56%] vs. 23% [95% CI: 18% to 27%]; p < 0.001). Men and younger patients with MINOCA were more likely to have myocarditis. Angiographically normal coronary arteries were associated with increased odds of myocarditis after adjustment for age and sex (adjusted odds ratio: 2.30; 95% CI: 1.12 to 4.71; p = 0.023). CONCLUSIONS: Patients with a provisional diagnosis of MINOCA are more likely to have CMR findings consistent with myocarditis if they have angiographically normal coronary arteries.

Cardiac AA amyloidosis in a patient with obstructive hypertrophic cardiomyopathy.

Cardiac amyloid A (AA) amyloidosis is rare. We present the case of a 72-year-old woman with obstructive hypertrophic cardiomyopathy (HCM) and biopsy-proven renal AA amyloidosis whose dyspnea and exercise intolerance had worsened over the previous year. Her AA amyloidosis was suspected to be secondary to chronic diverticulitis for which she had undergone hemicolectomy and sigmoidectomy 3 years prior. Echocardiographic findings were consistent with worsening left ventricular outflow tract obstruction at rest. Cardiac magnetic resonance imaging revealed patchy areas of midwall late gadolinium enhancement. Right ventricular endomyocardial biopsy did not reveal amyloid deposition, and cardiac technetium-99m pyrophosphate scintigraphy did not suggest transthyretin amyloidosis. The patient underwent septal myectomy with resection of an accessory papillary muscle. Pathological examination of the myectomy specimen was consistent with HCM. In addition, there was a thick layer of diffuse endocardial and vascular amyloid deposition that was identified as AA type by laser-microdissection with liquid chromatography-coupled tandem-mass spectrometry. This case report highlights the presence of 2 distinct disease processes occurring simultaneously and the importance of tissue diagnosis of AA amyloidosis, a condition that is not commonly associated with HCM.

Adverse Event Profile Associated with Prolonged Use of CentriMag Ventricular Assist Device for Refractory Cardiogenic Shock.

Several studies have investigated early outcomes with a surgical short-term ventricular assist device (VAD), but little is known about adverse event profile during prolonged support with a surgical short-term VAD. This is a retrospective analysis of 161 patients who received a CentriMag ventricular assist system (Abbott Laboratories, Abbott Park, IL) at our institution between January 2007 and June 2014. Device-related adverse events include major bleeding, infection, and stroke incidents occurring during CentriMag support. Cumulative frequency of adverse events was estimated by Nelson's nonparametric method. One hundred and forty-three (88.8%) patients had biventricular VAD and 18 (11.2%) had isolated left VAD. Median duration of support was 16 days (interquartile range [IQR]: 10-29). Mortality was 24.8% and 1 year overall survival is 51.8% (95% CI: 43.3-59.5%). The most common adverse event during support was major bleeding (n = 121, 75.1%). Ninety-five (59.0%) developed major infections such as pneumonia and urinary tract infection. Sixteen patients (10%) experienced stroke. Cumulative data analysis showed that stroke and reoperation caused by bleeding were rare beyond 30 days, whereas infection and nonsurgical bleeding events were directly related to support time. In conclusion, temporary VAD with CentriMag support is an effective treatment for patients in refractory cardiogenic shock. Despite its side effect, profile including a high rate of blood transfusion early in the immediate postoperative period of CentriMag support, aggressive use of the CentriMag support device has acceptable survival to discharge and 1 year survival.

Isolated Right Ventricular Mechanical Support: Outcomes and Prognosis.

Right ventricular (RV) failure that necessitates isolated mechanical support is extremely rare. Outcomes have not been described and are limited to case reports. We sought to evaluate this select group of patients and determine their 30 day and 1 year survival. We retrospectively reviewed the Mechanical Assist Device Database at Columbia University from 2007 to 2015. Inclusion criteria consisted of patients who received isolated RV assist devices (RVADs) without mechanical support of the left ventricle. We evaluated survival, duration of support, intensive care unit (ICU) length of stay, and adverse events. There were 55 patients who underwent RVAD placement between February 2007 and April 2015. Eleven of these patients received isolated RVADs in the absence of mechanical circulatory support of the left ventricle. Average duration of support was 13.6 days with a median duration of 12 days. Thirty day and 1 year survival was 72.7% and 54.6%, respectively. This case series is the first to describe 30 day and 1 year outcomes for patients with isolated RV mechanical support. We propose an interdisciplinary institutional algorithm based on our study population that maximizes medical therapy and then pursues invasive forms of mechanical support when end-organ damage persists.

Outcome of heart transplantation after bridge-to-transplant strategy using various mechanical circulatory support devices.

OBJECTIVES: Orthotopic heart transplantation (OHT) is limited by a chronic shortage of donors. With the evolution of technology, more patients have been bridged to transplant (BTT) through various pathways using various types of mechanical circulatory support. We compared short- and long-term outcomes among these various strategies of BTT. METHODS: We retrospectively reviewed 410 patients who had OHT between January 2009 and April 2015. Patients were divided into 4 groups according to BTT status: primary OHT without bridging (Group A, n = 246); bridge with implantable continuous-flow left ventricular assist device (CF-LVAD) (Group B, n = 130); bridge with short-term mechanical circulatory support (Group C, n = 16) and bridge with multiple mechanical circulatory supports, including short-term mechanical circulatory support and CF-LVAD (Group D, n = 18). Early and late outcomes after OHT were compared among the groups. RESULTS: The total duration of device support was 110.4 patient-years, 1.8 patient-years and 21.0 patient-years in Groups B, C and D, respectively. Patients who were bridged with CF-LVAD (Groups B and D) were more likely to have larger body size, blood type O, idiopathic dilated cardiomyopathy and ischaemic cardiomyopathy as an aetiology, lower total bilirubin level and longer waiting time on the United Network for Organ Sharing Status 1A. There was no statistical difference between the 4 groups in serum panel reactive antigen levels before OHT. Hospital mortality was 4% in Group A, 8% in Group B, 13% in Group C and 6% in Group D (P = 0.307). Post-transplant survival at 3 years was 80% in Group A, 82% in Group B, 75% in Group C and 88% in Group D (P = 0.752). CONCLUSIONS: BTT strategies using various mechanical circulatory support devices can provide comparable clinical outcomes to primary OHT. Flexibility in the use of both short-term mechanical circulatory support and CF-LVAD is necessary depending on the patient's background.

Combined Therapy of Ventricular Assist Device and Membrane Oxygenator for Profound Acute Cardiopulmonary Failure.

Short-term ventricular assist devices (ST-VADs) have been effective in treating the patients with refractory cardiogenic shock. Membrane oxygenators (MOs) can be added to the circuit for concomitant, profound refractory hypoxia. This study reports the outcomes of combined therapy in this portion of patients. This is a retrospective review of 166 patients who received an ST-biventricular assist device (BiVAD) or right ventricular assist device (RVAD) for cardiogenic shock between November 2007 and November 2014. An MO was added to the RVAD for profound hypoxia refractory to maximized ventilation. Patients were divided into two groups: 33 with (MO-VAD [MV]) and 133 without (VAD only [VO]) an MO. Survival to discharge and adverse events were compared between groups. More MV than VO patients were intubated (93.9% vs. 59.4%; p < 0.001) and on veno-arterial extracorporeal membrane oxygenator (VA-ECMO) (72.7% vs. 19.5%; p < 0.001) before implantation. Survival to discharge (51.5% MV vs. 52.6% VO; p = 0.515) and 1 year survival (54.4% MV vs. 48.6% VO; p = 0.955) were not significantly different. MV patients had more prolonged intubation (69.7% vs. 37.6%; p < 0.001), tracheostomies (39.4% vs. 16.5%; p = 0.008), and a higher risk for bleeding (p = 0.037). Patients suffering from cardiogenic shock with refractory hypoxia requiring combined ST-VAD and MO therapy appear to achieve similar mid-term survival despite increased risk for early complications.

Improved outcomes from extracorporeal membrane oxygenation versus ventricular assist device temporary support of primary graft dysfunction in heart transplant.

BACKGROUND: Primary graft dysfunction (PGD) is one of the most common causes of early death after orthotopic heart transplantation. Mechanical circulatory support devices are required for severe forms of PGD. Venoarterial extracorporeal membrane oxygenation (VA-ECMO) and temporary ventricular assist device (VAD) support have both been reported to be useful for severe PGD. METHODS: Between January 2007 and December 2015, 597 patients received a heart transplant at our center. Of those, severe PGD developed in 44 patients (7.4%), and they received a continuous-flow external VAD (n = 17) or VA-ECMO (n = 27) support within 24 hours after transplant. We compared early and late outcomes between groups. RESULTS: Baseline characteristics were similar between groups. Implantation of the temporary VAD required longer cardiopulmonary bypass time compared with VA-ECMO (323 ± 86 minutes vs 216 ± 65 minutes, p < 0.0001). Patients who received a VAD were more likely to have longer support time (14 ± 17 days vs 5.2 ± 3.9 days, p = 0.011), a higher incidence of major bleeding requiring chest reexploration (77% vs 30%, p = 0.0047), and a higher incidence of renal failure requiring renal replacement therapy (53% vs 11%, p = 0.0045) after surgery. Overall hospital mortality was 27%. In-hospital mortality for VAD and VA-ECMO patients were 41% and 19%, respectively (p = 0.16). Ten patients (59%) were weaned from VAD support, and 24 (89%) were weaned from VA-ECMO support after adequate graft function recovery (p = 0.03). The 3-year post-transplant survival was 41% in the VAD group and 66% in the VA-ECMO group (p = 0.13). CONCLUSIONS: For severe PGD, support with VA-ECMO appears to result in better clinical outcomes compared with VAD.

External carotid artery stenosis after internal and common carotid stenting.

BACKGROUND: The external carotid artery (ECA) can be an important collateral for cerebral perfusion in the presence of severe internal carotid artery (ICA) disease. ICA stenting that covers the ECA origin may put the ECA at increased risk of stenosis. Our objective was to determine the rate of ECA stenosis secondary to ICA stenting, determine predictive factors, and describe any subsequent associated symptoms. METHODS: We retrospectively reviewed clinical data on all ICA stents crossing the origin of the ECA placed by vascular surgeons at our institution. We analyzed patient demographics, comorbidities, stent type and sizes, as well as medication profile to determine predictors of ECA stenosis. RESULTS: Between 2005 and 2013, there were 72 (out of 119 total ICA stenting) patients (mean age 71, 68% male) who underwent placement of ICA stents that also crossed the origin of the ECA. Six patients (8.3%) had a significantly increased ECA stenosis postprocedure. There were no occlusions. All patients with ECA stenosis maintained patency of their ICA stent and were asymptomatic. Age, gender, comorbidities, stent type and size, and medication profile were not associated with ECA stenosis after stenting. CONCLUSIONS: ECA stenosis after ICA stenting covering the ECA origin is uncommon and not clinically significant in patients with patent ICA stents. The clinical significance of concurrent ECA and ICA stenosis after stenting is unclear as it is not captured here. The potential for ECA stenosis should not deter stenting across the ECA origin if necessary. Patient and stent factors are not predictive of ECA stenosis.

Imaging the glycome in living systems.

The glycome, the full complement of glycans that cells produce, is an attractive target for molecular imaging. Imaging of the glycome in living systems has recently been enabled via bioorthogonal chemical reporter-based approaches. In this chapter, we describe two approaches to introduce bioorthogonal chemical reporters (tags) onto cell surface fucosylated glycans and glycans bearing LacNAc disaccharides, respectively. The tagged glycans can then be conjugated to imaging probes via bioorthogonal click chemistry. Similar approaches can be extended to image other sectors of the glycome in living systems.

Anti-proliferative effects of O-acyl-low-molecular-weight heparin derivatives on bovine pulmonary artery smooth muscle cells.

Heparin (HP) inhibits the growth of several cell types in vitro including bovine pulmonary artery (BPA) smooth muscle cells (SMCs). In initial studies we discovered that an O-hexanoylated low-molecular-weight (LMW) HP derivative having acyl groups with 6-carbon chain length was more potent inhibitor of BPA-SMCs than the starting HP. We prepared several O-acylated LMWHP derivatives having 4-, 6-, 8-, 10-, 12-, and 18- carbon acyl chain lengths to determine the optimal acyl chain length for maximum anti-proliferative properties of BPA-SMCs. The starting LMWHP was prepared from unfractionated HP by sodium periodate treatment followed by sodium borohydride reduction. The tri-n-butylammonium salt of this LMWHP was O-acylated with butanoic, hexanoic, octanoic, decanoic, dodecanoic, and stearyl anhydrides separately to give respective O-acylated LMWHP derivatives. Gradient polyacrylamide gel electrophoresis (PAGE) was used to examine the average molecular weights of those O-acylated LMWHP derivatives. NMR analysis indicated the presence of one O-acyl group per disaccharide residue. Measurement of the inhibition of BPA-SMCS as a function of O-acyl chain length shows two optima, at a carbon chain length of 6 (O-hexanoylated LMWHP) and at a carbon chain length 12-18 (O-dodecanoyl and O-stearyl LMWHPs). A solution competition SPR study was performed to test the ability of different O-acylated LMWHP derivatives to inhibit fibroblast growth factor (FGF) 1 and FGF2 binding to surface-immobilized heparin. All the LMWHP derivatives bound to FGF1 and FGF2 but each exhibited slightly different binding affinity.

Analysis of glycosaminoglycans in stem cell glycomics.

Glycosaminoglycans (GAGs) play a critical role in the binding and activation of growth factors in cell signal transduction required for biological development. A glycomics approach can be used to examine GAG content, composition, and structure in stem cells in order to characterize their general differentiation. Specifically, this method may be used to evaluate chondrogenic differentiations by profiling for the GAG content of the differentiated cells. Here, embryonic-like teratocarcinoma cells, NCCIT, a developmentally pluripotent cell line, were used as a model for establishing GAG glycomic methods, but will be easily transferrable to embryonic stem cell cultures.

Effect of carboxyl-reduced heparin on the growth inhibition of bovine pulmonary artery smooth muscle cells.

Heparin (HP) inhibits the proliferation of bovine pulmonary artery smooth muscle cells (BPASMC's), among other cell types in vitro. In order to develop a potential therapeutic agent to reverse vascular remodeling, we are involved in deciphering the relationship between the native HP structure and its antiproliferative potency. We have previously reported the influence of the molecular size and the effects of various O-sulfo and N-acetyl groups of HP on growth-inhibitory activity. In this study, to understand the influence of carboxyl groups in the HP structure required for endogenous activity, a chemically modified derivative of native HP was prepared by converting the carboxyl groups of hexuronic acid residues in HP to primary hydroxyl groups. This modification procedure involves the treatment of HP with N-(3-dimethylaminopropyl)-N-ethylcarbodiimide followed by reduction with NaBH(4) to yield carboxyl-reduced heparin (CR-HP). When compared to the antiproliferative potency of native HP on cultured BPASMC's at three dose levels (1, 10, and 100 microg/mL), the CR-HP showed significantly less potency at all the doses. These results suggest that hexuronic acid residues in both major and variable sequences in HP are essential for the antiproliferative properties of native HP.

Antitumor effect of butanoylated heparin with low anticoagulant activity on lung cancer growth in mice and rats.

Whole unfractionated heparin can modestly decrease tumor growth, but the dose of heparin is limited by its anticoagulant properties. To overcome this limitation, we modified the chemical structure of heparin and have prepared a heparin derivative by O-acylating low molecular weight heparin with butyric anhydride, producing a more potent antiproliferative compound, which is only weakly anticoagulant so that the dose may be escalated without threat of hemorrhage. In this study, we investigated the effect of this chemically modified heparin, butanoylated heparin, on the growth of lung cancer in vitro and in vivo. We found that butanoylated heparin a) significantly inhibited lung cancer cell proliferation in vitro and lung cancer growth in mice and rats; b) had very low anticoagulant effect; c) had no significant toxicity on heart, liver, kidney and lung; d) significantly although modestly induced apoptosis and decreased expression of the cell proliferation pathway consisting of mutant p53, phospho-Rb and E2F1 expression in the tumor tissues. We also found that butanoylated heparin significantly inhibited CXCL12 and CXCR4 expression, suggesting that CXCL12/CXCR4 axis may be involved in regulation of tumor growth inhibition by heparin. We concluded that chemically modified butanoylated heparin has potent antiproliferative activity against lung cancer and may represent a new chemical therapeutic agent for cancer patients.

Analysis of pharmaceutical heparins and potential contaminants using (1)H-NMR and PAGE.

In 2008, heparin (active pharmaceutical ingredient, API) lots were associated with anaphylactoid-type reactions. Oversulfated chondroitin sulfate (OSCS), a semi-synthetic glycosaminoglycan (GAG), was identified as a contaminant and dermatan sulfate (DS) as an impurity. While DS has no known toxicity, OSCS was toxic leading to patient deaths. Heparins, prepared before these adverse reactions, needed to be screened for impurities and contaminants. Heparins were analyzed using high-field (1)H-NMR spectroscopy. Heparinoids were mixed with a pure heparin and analyzed by (1)H-NMR to assess the utility of (1)H-NMR for screening heparin adulterants. Sensitivity of heparinoids to deaminative cleavage, a method widely used to depolymerize heparin, was evaluated with polyacrylamide gel electrophoresis to detect impurities and contaminants, giving limits of detection (LOD) ranging from 0.1% to 5%. Most pharmaceutical heparins prepared between 1941 and 2008 showed no impurities or contaminants. Some contained DS, CS, and sodium acetate impurities. Heparin prepared in 2008 contained OSCS contaminant. Heparin adulterated with heparinoids showed additional peaks in their high-field (1)H-NMR spectra, clearly supporting NMR for monitoring of heparin API with an LOD of 0.5-10%. Most of these heparinoids were stable to nitrous acid treatment suggesting its utility for evaluating impurities and contaminants in heparin API.

Sulfonation of papain-treated chitosan and its mechanism for anticoagulant activity.

The novel low-molecular-weight chitosan polysulfate (MW 5120-26,200 Da) was prepared using the depolymerization of chitosan with papain (EC. 3.4.22.2). The sulfonation of depolymerized products was performed using chlorosulfonic acid in N,N-dimethylformamide under semi-heterogeneous conditions. The structures of the products were characterized by FTIR, (13)C NMR, and (1)H NMR (1D, 2D NMR) spectroscopy. The present study sheds light on the mechanism of anticoagulant activity of chitosan polysulfate. Anticoagulant activity was investigated by an activated partial thromboplastin assay, a thrombin time assay, a prothrombin time assay, and thrombelastography. Surface plasmon resonance also provided valuable data for understanding the relationship between the molecular binding of sulfated chitosan to two important blood clotting regulators, antithrombin III and heparin cofactor II. These results show that the principal mechanism by which this chitosan polysulfate exhibits anticoagulant activity is mediated through heparin cofactor II and is dependent on polysaccharide molecular weight.