Synthesis and pharmacological evaluation of acylhydroquinone derivatives as potent antiplatelet agents

Platelets are the smallest blood cells, and their activation (platelet cohesion or aggregation) at sites of vascular injury is essential for thrombus formation. Since the use of antiplatelet therapy is an unsolved problem, there are now focused and innovative efforts to develop novel antiplatelet compounds. In this context, we assessed the antiplatelet effect of an acylhydroquinone series, synthesized by Fries rearrangement under microwave irradiation, evaluating the effect of diverse acyl chain lengths, their chlorinated derivatives, and their dimethylated derivatives both in the aromatic ring and also the effect of the introduction of a bromine atom at the terminus of the acyl chain. Findings from a primary screening of cytotoxic activity on platelets by lactate dehydrogenase assay identified 19 non-toxic compounds from the 27 acylhydroquinones evaluated. A large number of them showed IC₅₀ values less than 10 µM acting against specific pathways of platelet aggregation. The highest activity was obtained with compound 38, it exhibited sub-micromolar IC₅₀ of 0.98 ± 0.40, 1.10 ± 0.26, 3.98 ± 0.46, 6.79 ± 3.02 and 42.01 ± 3.48 µM against convulxin-, collagen-, TRAP-6-, PMA- and arachidonic acid-induced platelet aggregation, respectively. It also inhibited P-selectin and granulophysin expression. We demonstrated that the antiplatelet mechanism of compound 38 was through a decrease in a central target in human platelet activation as in mitochondrial function, and this could modulate a lower response of platelets to activating agonists. The results of this study show that the chemical space around ortho-carbonyl hydroquinone moiety is a rich source of biologically active compounds, signaling that the acylhydroquinone scaffold has a promising role in antiplatelet drug research.

Association of aspirin and other non-steroidal anti-inflammatory drugs with bleeding complications in image-guided musculoskeletal biopsies

OBJECTIVE

To evaluate the safety of continuing aspirin and other non-steroidal anti-inflammatory drugs (NSAID) in patients undergoing image-guided musculoskeletal biopsies.

MATERIAL AND METHODS

Prior to October 2017, patients undergoing image-guided musculoskeletal biopsy had aspirin and NSAIDs withheld for the preceding 5-7 days. The policy changed in October 2017 based on new guidelines from the Society of Interventional Radiology such that aspirin and other NSAIDs were not withheld. A retrospective review of patient records was performed for all biopsies prior to and after the policy change to assess for differences in biopsy-related bleeding complications. Additional clinical and biopsy factors including age, gender, liver disease, coagulopathy, biopsy tissue type, and histological diagnosis were assessed.

RESULTS

In the pre-policy change group, there were 1853 total biopsies with 43 biopsy-related bleeding complications (2.3%). Within this group, 362 patients were on aspirin with 7 bleeding complications (1.9%) and 260 patients were on NSAIDs with 5 bleeding complications (1.9%). There were 409 total biopsies in the post-policy change group and 7 bleeding complications (1.7%). Within this group, 71 patients were on aspirin with 1 bleeding complication (1.4%). No bleeding complications were recorded in patients on NSAIDs (0%). There was no significant difference in bleeding complication between the pre- and post-policy change groups overall (p = 0.58) and in patients on aspirin (p = 1.00) or other NSAIDs (p = 1.00).

CONCLUSION

Bleeding complications for musculoskeletal biopsies are rare. Leaving patients on aspirin or other NSAIDs during a musculoskeletal biopsy does not increase the incidence of bleeding complications.

A case report of a coronary artery fistula to coronary sinus with giant aneurysm: risk does not end with repair

Background

Isolated coronary arteriovenous fistulas are extremely rare, accounting for 0.08–0.4% of all congenital heart disease. Closure of the fistula is recommended in cases of large dimensions, relevant left–right shunt, or ischaemic events. Thrombosis of the coronary aneurysms may occur as a postoperative complication.

Case summary

We report a case of a coronary fistula between the circumflex artery and coronary sinus with giant aneurysm. After a failed percutaneous closure attempt, the patient was surgically treated without major postoperative complications. Despite therapeutic anticoagulation and antiplatelet therapy, she presented at clinical follow-up with thrombosis of the dilated coronary artery without signs or symptoms of ischaemia.

Discussion

Management of coronary artery fistula may be challenging in cases in which initial percutaneous closure is unsuccessful. This particular case also highlights the importance of close follow-up, despite optimal therapy, to detect potentially lethal complications related to the low flow in the dilated coronary aneurysm.

Risks and complications of robot-assisted radical prostatectomy (RARP) in patients receiving antiplatelet and/or anticoagulant therapy: a retrospective cohort study in a single institute

The objective of the study was to evaluate the risk of bleeding complications in patients undergoing robot-assisted radical prostatectomy (RARP) while taking antiplatelet (AP) and/or anticoagulant (AC) agents. We analyzed the data of 334 patients undergoing RARP from May 2015 to May 2019. Patients were categorized into AP, AC, and control groups; the bleeding complications were compared among them. The end points were the estimated blood loss, decrease in hemoglobin level, and bleeding complications. The patient characteristics did not differ significantly among groups, with the exception of ASA scores, which were significantly higher in the AP and AC groups vs. the control group. The estimated blood loss and hemoglobin decrease were not significantly different between the AP and AC groups and the control group. The frequency of bleeding complications did not differ significantly between the AP and the control groups, but was significantly higher in the AC vs. the control group (4.3% in the AP and 23.5% in the AC group vs. 3.7% in the control group; P = 0.63 and P < 0.01, respectively). There was no significant difference in bleeding complications between the AP continuation (continuation of a single AP) and the AP interruption group or between the heparin bridging and the AC interruption group. All bleeding complications observed in the AC group occurred after resuming AC therapy. RARP can be performed safely with continuation of a single AP, and in patients taking ACs by interrupting these agents or via heparin bridging, without increasing intraoperative bleeding, whereas postoperative bleeding complications may increase after resuming ACs.

Antithrombotic treatment of asymptomatic carotid atherosclerosis: a medical dilemma

Carotid artery atherosclerosis (CAAS) is a common finding in asymptomatic subjects evaluated for cardiovascular (CV)-risk stratification. Besides the careful control of CV-risk factors, antithrombotic agents, and in particular aspirin, may be considered for primary prevention in patients at CV-risk. However, there is strong controversy on the use of aspirin in primary prevention. Even if several studies confirmed the association between CAAS and CV-events, CAAS is not universally recognized as an independent risk factor and the choice to use aspirin as primary prevention in these patients remains a medical dilemma. Here we review the available evidence on the prognostic value of asymptomatic CAAS for major CV-events and on the utility of antithrombotic agents in this population. We conclude that the detection of asymptomatic CAAS can not be considered as a direct indication to carry out primary prophylaxis with antithrombotic drugs, and the choice to use aspirin should be made only after the careful estimate of the individual's CV-and hemorrhagic risk.

Long-Term Follow-Up of Pediatric Patients After Congenital Coronary Artery Fistula Closure

The surgical closure of congenital coronary artery fistulas (CAF) is associated with excellent immediate outcomes. Few studies have investigated the long-term prognosis in patients who have undergone surgery for the closure of CAF or differentiated among types of CAF or types of surgical procedures. In this study, we performed clinical examinations and computed tomography angiography (CTA) to characterize outcomes after CAF closure in pediatric patients. The medical records of 79 pediatric patients who underwent surgical closure of CAF were retrospectively reviewed. The median age of the patients included in the study at the time of surgery was 3.4 years (range 0.2 to 15.3 years). The patients had been followed up for 11 years (range 1 to 17 years) with electrocardiography, echocardiography, and coronary CTA. There were 67 medium-to-large CAF and 12 small CAF. Twenty-six (32.9%) CAF arose from the branch coronary artery (proximal type); the others arose from the parent coronary artery (distal type). The surgical procedure included endocardial closure in 16 cases, epicardial distal ligation in 51 cases, epicardial proximal and distal ligation in 12 cases. There was no instance of perioperative death among the cases included in the study. Twenty-eight patients were treated with antiplatelet medication postoperatively. No patient required re-operation during the follow-up period. Coronary thrombi were detected in 27 patients (34.2%). There was no instance of myocardial ischemia related to thrombosis. Among the patients with thrombosis, 26 had medium-to-large CAF (96.3%), and 23 had distal-type CAF (85.2%). Average age at surgery was higher among the patients with thrombosis than among the patients without thrombosis (7.4 years vs. 3.3 years, t = 5.509, P = 0.000). Among the patients with distal-type CAF, thrombosis was more common among the patients treated with ligation than treated with endocardial closure (41.5% vs. 16.7%, χ² = 3.742_, P = 0.043). There was no difference in risk for thrombosis between the patients who did vs. did not receive antiplatelet therapy (P = 0.436). The most common complication after CAF closure was thrombosis. Increased risk for thrombosis was associated with large fistulae, distal-type CAF, and older age at presentation. Antiplatelet treatment did not appear to decrease the risk of thrombosis. Among patients with distal-type CAF, risk for thrombosis was lower among patients treated with endocardial closure, compared with patients treated with epicardial ligation.

Guidelines for Transrectal Ultrasonography-Guided Prostate Biopsy: Korean Society of Urogenital Radiology Consensus Statement for Patient Preparation, Standard Technique, and Biopsy-Related Pain Management

The Korean Society of Urogenital Radiology (KSUR) aimed to present a consensus statement for patient preparation, standard technique, and pain management in relation to transrectal ultrasound-guided prostate biopsy (TRUS-Bx) to reduce the variability in TRUS-Bx methodologies and suggest a nationwide guideline. The KSUR guideline development subcommittee constructed questionnaires assessing prebiopsy anticoagulation, the cleansing enema, antimicrobial prophylaxis, local anesthesia methods such as periprostatic neurovascular bundle block (PNB) or intrarectal lidocaine gel application (IRLA), opioid usage, and the number of biopsy cores and length and diameter of the biopsy needle. The survey was conducted using an Internet-based platform, and responses were solicited from the 90 members registered on the KSUR mailing list as of 2018. A comprehensive search of relevant literature from Medline database was conducted. The strength of each recommendation was graded on the basis of the level of evidence. Among the 90 registered members, 29 doctors (32.2%) responded to this online survey. Most KSUR members stopped anticoagulants (100%) and antiplatelets (76%) one week before the procedure. All respondents performed a cleansing enema before TRUS-Bx. Approximately 86% of respondents administered prophylactic antibiotics before TRUS-Bx. The most frequently used antibiotics were third-generation cephalosporins. PNB was the most widely used pain control method, followed by a combination of PNB plus IRLA. Opioids were rarely used (6.8%), and they were used only as an adjunctive pain management approach during TRUS-Bx. The KSUR members mainly chose the 12-core biopsy method (89.7%) and 18G 16-mm or 22-mm (96.5%) needles. The KSUR recommends the 12-core biopsy scheme with PNB with or without IRLA as the standard protocol for TRUS-Bx. Anticoagulants and antiplatelet agents should be discontinued at least 5 days prior to the procedure, and antibiotic prophylaxis is highly recommended to prevent infectious complications. Glycerin cleansing enemas and administration of opioid analogues before the procedure could be helpful in some situations. The choice of biopsy needle is dependent on the practitioners' situation and preferences.

Comparison of antithrombotic strategies in patients with cryptogenic stroke and patent foramen ovale: an updated meta-analysis

PURPOSE

Patients with patent foramen ovale (PFO) and cryptogenic ischemic stroke (CS) are at risk for stroke recurrence. The optimal antithrombotic strategy in patients who undergo medical management is still debated.

METHODS

We systematically searched the literature for studies that reported on cerebrovascular event recurrences and/or death in patients with PFO treated with oral anticoagulation (OAC) or antiplatelet therapy (APT) for secondary prevention of CS. The efficacy endpoints were stroke recurrence and the composite of stroke, transient ischemic attack or all-cause death. Major bleedings represented the safety endpoint.

RESULTS

A total of 16 studies with 3953 patients (OAC = 1527, APT = 2426) were included. Weighted mean follow-up was 2.9 years. OAC was associated with a significant reduction in the risk of stroke compared with APT (RR 0.65; 95% CI 0.44-0.95; ARR 2%, NNT 49), while no difference was found regarding the composite outcome (RR 0.78; 95% CI 0.57-1.07) and the safety outcome (RR 1.57; 95% CI 0.85-2.90; p = 0.15).

CONCLUSIONS

OAC was more effective than APT in reducing the risk of stroke recurrence in patients with PFO and CS, without a significant increase in the risk of major bleedings. Our findings support the need for further randomized data focused on the comparison of antithrombotic strategies in this setting.

Data on antiplatelet aggregation, anticoagulation and antioxidant activities of Canna edulis Ker rhizome and its secondary metabolites

Canna edulis Ker rhizome has been used in Traditional Vietnamese Medicine to prevent and treat heart diseases without thorough scientific evidence. The data presented in this article characterize the antiplatelet aggregation, anticoagulant and antioxidant activity of C. edulis rhizome extracts and the bio-guided isolation of bioactive compounds from the active fraction. The data on tested bioactivities of isolated compounds were also provided. The inhibitory effect on adenosine diphosphate- and collagen-induced human platelet aggregation was evaluated through three parameters: percentage inhibition of platelet aggregation, aggregation velocity and area under the platelet aggregation curve. Prothrombin time, activated partial thromboplastine time and thrombine time were measured to examine the anticoagulant activity. The free radical scavenging ability was assessed with DPPH and ABTS assays. The structures of compounds were elucidated by NMR and MS spectroscopic methods. The data showed that the ethyl acetate fraction showed the most potent antiplatelet aggregation, anticoagulant and antioxidant activity. Seven known compounds: 5-hydroxy-6-methyl-2H-pyran-2-one (1), epimedokoreanone A (2), nepetoidin B (3), ferulic acid (4), caffeic acid (5), hydroxytyrosol (6), and 1H-indole-3-carboxaldehyde (7) were isolated from this active fraction. Moreover, this article provided experimental data on antiplatelet effect of epimedokoreanone A (2) and nepetoidine B (3), anticoagulant and antioxidant activity of epimedokoreanone A (2) and also antiplatelet and antioxidant activity of 5-hydroxy-6-methyl-2H-pyran-2-one (1).

Incidence of major adverse cardiovascular events with genotype test guided antiplatelet treatment strategy after percutaneous coronary intervention

Objective

To estimate the incidence of major adverse cardiovascular events (MACE) with genotype test-guided antiplatelet therapy in patients undergoing percutaneous coronary intervention (PCI) for acute coronary syndrome.

Methods

Patients who had undergone PCI for acute coronary syndrome as well as stable coronary artery disease were recruited. Salivary samples were obtained from these patients and genotyped for CYP2C19∗2, CYP2C19∗3 variations by sequencing method (GAAP x method). Patients were categorized as normal (GG, GG) (29%), intermediate (AG) (52%) or poor metabolizes (homozygous variant AA) (19%). Dual antiplatelets were given based on the genotyping data. Poor metabolizes received newer agent (ticagrelor), intermediate metabolizes received double-dose of clopidogrel and normal metabolizes received therapeutic doses of clopidogrel. All subjects were followed-up for six months.

Results

Based on the genotyping data of CYP2C19∗2 and CYP2C19∗3 variations, it was found that most patients were categorized as ‘intermediate’ (78, 51.65%), followed by ‘normal’ (43, 28.48%) and ‘poor’ metabolizes (30, 19.87%). Only 3 (1.5%) of 151 patients reported MACE at follow-up.

Conclusions

Genotyping for CYP2C19 variations to assess clopidogrel resistance in patients undergoing PCI and subsequent drug selection helps reduce MACE after coronary intervention.

An updated drug profile of ticagrelor with considerations on the treatment of patients with coronary artery disease and diabetes mellitus

INTRODUCTION

Ticagrelor is an antiplatelet agent acting through direct and reversible competitive inhibition of the platelet P2Y₁₂ receptor. While the clinical merits of ticagrelor in patients who experienced an acute coronary syndrome are widely accepted, its role in stable coronary artery disease is less established. Recently, large-scale trials of ticagrelor have been published in this setting, including a trial in patients with diabetes mellitus (DM).

AREAS COVERED

This review aims to inform about recent findings on ticagrelor, by appraising the current body of evidence on its use in different clinical scenarios, particularly in DM, ranging from pharmacology to clinical outcomes and future directions.

EXPERT OPINION

The results of the THEMIS trial, conducted in DM patients with stable coronary artery disease and no prior stroke or myocardial infarction, showed that although ticagrelor in addition to aspirin reduced the risk of ischemic events, this was associated with a parallel increase in bleeding complications. However, patients with history of percutaneous coronary intervention seemed to benefit more from adjunctive ticagrelor therapy. Careful bleeding and ischemic risk stratification remains crucial to define the best antithrombotic strategy for the individual patient.

Prior antiplatelet therapy in patients undergoing endovascular treatment for acute ischemic stroke: Results from the MR CLEAN Registry

Background

Antiplatelet therapy may increase the risk of symptomatic intracranial hemorrhage after endovascular treatment for ischemic stroke but may also have a beneficial effect on functional outcome. The aim of this study is to compare safety and efficacy outcomes after endovascular treatment in patients with and without prior antiplatelet therapy.

Methods

We analyzed patients registered in the MR CLEAN Registry between March 2014 and November 2017, for whom data on antiplatelet therapy were available. We used propensity score nearest-neighbor matching with replacement to balance the probability of receiving prior antiplatelet therapy between the prior antiplatelet therapy and no prior antiplatelet therapy group and adjusted for baseline prognostic factors to compare these groups. Primary outcome was symptomatic intracranial hemorrhage. Secondary outcomes were 90-day functional outcome (modified Rankin Scale), successful reperfusion (extended thrombolysis in cerebral infarction score ≥2B) and 90-day mortality.

Results

Thirty percent (n = 937) of the 3154 patients were on prior antiplatelet therapy, who were matched to 477 patients not on prior antiplatelet therapy. Symptomatic intracranial hemorrhage occurred in 74/937 (7.9%) patients on prior antiplatelet therapy and in 27/477 (5.6%) patients without prior antiplatelet therapy adjusted odds ratio 1.47, 95% confidence interval 0.86–2.49. No associations were found between prior antiplatelet therapy and functional outcome (adjusted common odds ratio 0.87, 95% confidence interval 0.65–1.16), successful reperfusion (adjusted odds ratio 1.23, 95% confidence interval 0.77–1.97), or 90-day mortality (adjusted odds ratio 1.15, 95% confidence interval 0.86–1.54).

Conclusion

We found no evidence of an association of prior antiplatelet therapy with the risk of symptomatic intracranial hemorrhage after endovascular treatment, nor on functional outcome, reperfusion, or mortality. A substantial beneficial or detrimental effect of antiplatelet therapy on clinical outcome cannot be excluded. A randomized clinical trial comparing antiplatelet therapy versus no antiplatelet therapy is needed.

A case report of absolute thrombocytopenia with ticagrelor

BACKGROUND

We report a rare case of absolute thrombocytopenia with ticagrelor after 6 h of single loading dose of ticagrelor.

CASE SUMMARY

A 68-year-old male with ischaemic cardiomyopathy, hypertension, and dyslipidaemia presented with chest pain. He was found to be in new-onset atrial flutter and ruled in for a non-ST-segment elevation myocardial infarction. An echocardiogram showed decreased left ventricular ejection fraction, estimated at 15-20% and serum troponin peaked at 0.2 ng/dL, baseline platelet count was 203 × 10³/µL. He underwent a drug-eluting stent placement to the right coronary artery with excellent angiographic results. He received 3000 units of unfractionated heparin and 180 mg of ticagrelor during the procedure. About 6 h after the procedure, he had coffee ground emesis. A complete blood count revealed a platelet count of 2 × 10³ and 0 × 10³/µL on repeat testing. Peripheral smear did not show any evidence of platelet clumping and schistocytes, serum haptoglobin and lactate dehydrogenase were normal. Ticagrelor and heparin were discontinued, while the aspirin was continued. Five units of platelet were transfused. The platelet count improved to 200 × 10³/µL. Since his CHADS₂VASC score was 3, he was discharged on apixaban and clopidogrel in addition to other medication. No thrombocytopenia was seen on outpatient follow-up.

DISCUSSION

The common side effects of ticagrelor include bleeding, dyspnoea, gynaecomastia, and rarely thrombotic thrombocytopenic purpura. Although extremely rare, absolute or profound thrombocytopenia can occur with ticagrelor, hours after administration and should be considered when other potential causes of thrombocytopenia have been ruled out.

Early Anticoagulation or Antiplatelet Therapy Is Critical in Craniocervical Artery Dissection: Results from the COMPASS Registry

INTRODUCTION

Craniocervical artery dissection (CeAD) is a leading cause of stroke in the young patient population. Recent studies reported a low rate of major adverse cardiac events (MACEs) in patients with CeAD, with no significant difference between patients randomized to anticoagulation or antiplatelet therapy.

OBJECTIVE

To compare the effectiveness of anticoagulation and antiplatelet therapy in patients with CeAD.

METHODS

All CeAD patients from 2015 to 2017 were consecutively identified by an electronic medical record-based application and enrolled in this prospective longitudinal registry. CeAD was confirmed by imaging and graded using the Denver scale for blunt cerebrovascular injury. Patients were followed for 12 months for MACE defined as stroke, transient ischemic attack (TIA), or death.

RESULTS

The cohort included 111 CeAD patients (age 53 ± 15.9 years, 56% Caucasian, 50% female). CeAD was detected by magnetic resonance (5%), computed tomography (88%), or catheter angiography (7%). CeAD was noted in the carotid (59%), vertebral (39%), and basilar (2%) arteries, 82% of which were extracranial dissections. CeAD was classified as grade I, II, III, and IV in 16, 33, 19, and 32%, respectively. A total of 40% of dissections were due to known trauma. A predisposing factor was noted in the majority (78%) of patients, including violent sneezing (21%), carrying a heavy load (19%), sports/recreational activity (11%), chiropractic manipulation (9%), abrupt/prolonged rotation of head (9%), and prolonged phone use (9%). At presentation, 41% had a stroke, 5% had TIA, 39% had headache, and 36% were asymptomatic. Favorable outcome defined as a modified Rankin Scale score of 0-2 was noted in 68% at 3 months and 71% at 12 months. The rate of MACEs at 3 and 12 months was 11 and 14%, respectively, with more events observed in patients who were not receiving anticoagulation/antiplatelet therapy due to contraindications (p = 0.008).

CONCLUSIONS

We report diagnostic characteristics, as well as short- and long-term outcomes of CeAD. A high MACE rate was observed within the first 2 weeks of CeAD diagnosis, notably in patients not initiated on anticoagulation or antiplatelet therapy.

Racial and Gender Disparity in Achieving Optimal Medical Therapy for Inpatients with Peripheral Artery Disease

Best medical therapy for peripheral artery disease (PAD) includes statin and anti-platelet agents, a combination shown to decrease rates of major cardiovascular events. Despite these findings, many patients remain undertreated and the objective of this project was to investigate the rate of initiating anti-platelet and statin therapy for inpatients newly diagnosed with PAD with a focus on disparities by race and sex. A retrospective chart review of inpatients with newly diagnosed PAD was performed between January 1, 2016 to December 31, 2016 at a single institution. Demographics and comorbid conditions were collected. Primary outcomes included antiplatelet and statin prescription at discharge. The 44 patients included in this study were predominantly male (59% vs. 41%) and African American (61% vs. 39%). Between admission and discharge, prescriptions rose from 70% to 82% for statin and 82% to 91% for anti-platelet agents. Vascular specialists were more successful than non-vascular specialists at initiating medical therapy, with statin prescriptions increasing 22% and anti-platelet prescriptions climbing 23% for those admitted to a vascular specialist. Interestingly, when the ABI was reported in the normal range, rates of statin initiation were particularly compromised at only 40%. For the total patient sample, those discharged without a statin were more commonly African American (63%) and the majority were female (67%). All patients discharged without an antiplatelet were African American and 50% were females. Despite national guidelines, patients with PAD continue to be discharged without optimal medical therapy. This study suggests that obstacles to initiation may include race, sex, admitting service, or presence of a normal ABI. Further investigation is warranted to determine effective avenues for provider education and system-wide initiatives.

Advance of antithrombotic treatment in patients with cerebral microbleed

With the elder proportion increasing and the antithrombotic agents widely using as well as the newly magnetic resonance imaging sequence emerging, the detection rate of cerebral microbleed (CMB) is gradually raising in recent years. As we all know that CMB mainly reflects the severity of deeply small vessel lesions, which predicts hemorrhagic transformation. Whereby, to some patients with both CMB and remarkable antithrombotic indication, treatment becomes a dilemma. We have to face the challenge of weighing the pros and cons of both drug indication and bleeding risk when making a proper decision for patients. This study summarized recent advance on CMB diagnosis and treatment, to provide a useful reference to physicians in their clinical practice.

High-performance thin-layer chromatography fingerprinting, total phenolic and total flavonoid contents and anti-platelet-aggregation activities of Prosopis farcta extracts

Cardiovascular diseases are a leading cause of worldwide death and excessive platelet is closely related with their pathogenesis. Different plants and natural compounds have demonstrated anti-platelet effects. The aim of this study was to report the high-performance thin-layer chromatography (HPTLC) fingerprinting and anti-platelet-aggregation activities of different leaf extracts (n-hexane, chloroform, ethyl acetate, methanol and aqueous) of Prosopis farcta (Syrian mesquite) plant. The results showed a 100% inhibition of aggregation activity after plasmatic adenosine diphosphate (ADP) aggregation activation of ethyl acetate, ethanolic, methanolic and aqueous extracts, at 60 mg/mL concentration. The IC50 ADP value of these extracts ranged between 4.07 and 11.39 mg/mL. Moreover, these extracts reported the highest amounts of phenolic and flavonoid contents. In conclusion, phytochemicals present in P. farcta leaves have anti-platelet-aggregation activities. Future studies are needed to identify the compounds with anti-platelet potential present in P. farcta.

Post-extraction bleeding complications in patients on uninterrupted dual antiplatelet therapy-a prospective study

BACKGROUND

Dental surgeons consider patients on antiplatelet therapy (APT) to be at a risk for perioperative bleeding during dental extraction. This fear often prompts them to consider a temporary withdrawal of the medication for a few days before extraction. Such withdrawal can have serious consequences, especially in patients on dual antiplatelet therapy (DAPT).

OBJECTIVES

The purpose of this study was to analyze if patients on uninterrupted DAPT undergoing dental extractions had an increased risk of bleeding complications when compared with patients on no antiplatelet therapy.

METHODS

This prospective study included 120 DAPT patients and an equal number of age- and gender-matched non-APT patients undergoing dental extractions. Immediate and delayed bleeding complications in both groups were recorded. Interventions required to control the post-extraction hemorrhage were also analyzed.

RESULTS

Duration of DAPT medication ranged from 6 months to 13 years. Post-percutaneous coronary intervention was the most common cause for DAPT. A vast majority of patients in both groups underwent extraction of one or two teeth. Patients on DAPT had a 7-fold increased risk of immediate bleeding complications when compared with control group. All bleeding episodes were controlled with local hemostatic measures. Transalveolar extractions and localized periodontitis had a significant relationship to bleeding complications.

CONCLUSION

This study observed an increase in the risk of prolonged bleeding in uninterrupted DAPT patients undergoing dental extractions. Bleeding episodes were amenable to local hemostatic measures with favorable outcomes.

CLINICAL RELEVANCE

Dental extractions in patients on uninterrupted DAPT can be done safely. Resorting to temporary withdrawal of DAPT due to a fear of excessive bleeding is unnecessary.

Inosine, an endogenous purine nucleoside, avoids early stages of atherosclerosis development associated to eNOS activation and p38 MAPK/NF-kB inhibition in rats

Atherosclerosis is a multifactorial chronic disease, initiated by an endothelial dysfunction. Adenosine and its analogs can change a variety of inflammatory diseases and has shown important effects at different disease models. Inosine is a stable analogous of adenosine, but its effects in inflammatory diseases, like atherosclerosis, have not yet been studied. The aim of this study was to evaluate the pharmacological properties of inosine, administered sub chronically in a hypercholesterolemic model. Male Wistar rats were divided into four groups: control group (C) and control + inosine (C + INO) received standard chow, hypercholesterolemic diet group (HCD) and HCD + inosine (HCD + INO) were fed a hypercholesterolemic diet. At 31st experimentation day, the treatment with inosine was performed for C + INO and HCD + INO groups once daily in the last 15 days. We observed that the hypercholesterolemic diet promoted an increase in lipid levels and inflammatory cytokines production, while inosine treatment strongly decreased these effects. Additionally, HCD group presented a decrease in maximum relaxation acetylcholine induced and an increase in contractile response phenylephrine induced when compared to the control group, as well as it has presented an enhancement in collagen and ADP-induced platelet aggregation. On the other hand, inosine treatment promoted a decrease in contractile response to phenylephrine, evoked an improvement in endothelium-dependent vasorelaxant response and presented antiplatelet properties. Moreover, inosine activated eNOS and reduced p38 MAPK/NF-κB pathway in aortic tissues. Taken together, the present results indicate inosine as a potential drug for the treatment of cardiovascular disorders such as atherosclerosis.

Effect of antiplatelet therapy on minor dental procedures

Introduction:

Minor oral surgical procedures are very common. Acetylsalicylic acid generically known as aspirin is used clinically as an analgesic, antipyretic, anti-inflammatory, and as a medication to prevent platelet aggregation.

Objective:

The aim of this study was to determine if aspirin or clopidogrel was associated with bleeding after minor oral surgical procedures.

Materials and Methods:

One hundred patients who were planned for extraction of the third molar were divided into two groups. In Group A, patients on antiplatelets were included and in Group B, patients who discontinued the drug before 5 days of procedure were included. The bleeding time of all patients was checked before extraction. The surgical procedure involved simple extraction of a single third molar tooth under local anesthesia. The extraction socket was sutured with 3–0 silk. A pressure pack of gauze was given for 1 h. Bleeding after 1 h and 24 h was compared between two groups. A Chi-square test was used to compare the variables.

Results:

None of the patients showed active bleeding in the postoperative period. The results for postsurgical bleeding were statistically insignificant with P = 0.05.

Conclusion:

Minor surgical procedures such as single-tooth extraction can be carried out without discontinuation of the antiplatelet therapy.

Management of antiplatelet or anticoagulant therapy in endoscopy: A review of literature

Endoscopic procedures hold a basal risk of bleeding that depends on the type of procedure and patients’ comorbidities. Moreover, they are often performed in patients taking antiplatelet and anticoagulants agents, increasing the potential risk of intraprocedural and delayed bleeding. Even if the interruption of antithrombotic therapies is undoubtful effective in reducing the risk of bleeding, the thromboembolic risk that follows their suspension should not be underestimated. Therefore, it is fundamental for each endoscopist to be aware of the bleeding risk for every procedure, in order to measure the risk-benefit ratio for each patient. Moreover, knowledge of the proper management of antithrombotic agents before endoscopy, as well as the adequate timing for their resumption is essential.

This review aims to analyze current evidence from literature assessing, for each procedure, the basal risk of bleeding and the risk of bleeding in patients taking antithrombotic therapy, as well as to review the recommendation of American society for gastrointestinal endoscopy, European society of gastrointestinal endoscopy, British society of gastroenterology, Asian pacific association of gastroenterology and Asian pacific society for digestive endoscopy guidelines for the management of antithrombotic agents in urgent and elective endoscopic procedures.

In Vitro Assay of Quinoa (Chenopodium quinoa Willd.) and Lupin (Lupinus spp.) Extracts on Human Platelet Aggregation

Cardiovascular disease (CVD) is the leading cause of death throughout the world. A major risk factor for CVD is platelet aggregation. Various plant extracts exhibit anti-aggregatory action in vitro. The dietary intake of traditional plant crops such as quinoa (Chenopodium quinoa Willd) and lupin (Lupinus spp., Fabaceae family), highly recognized for their high nutritional value, is increasing worldwide. The aim of the study was to assay possible antiplatelet effects of quinoa and lupin bean extracts in vitro. The proximate chemical composition of quinoa grains and the three most widely known lupin cultivars: blue (L. angustifolius), yellow (L. luteus or mutabilis) and white (L. albus) grown in Chile were analyzed. The anti-aggregation activity of the ethanol extracts of the crops was assayed using flow cytometry in ADP-stimulated human platelets, and their inhibition of the maximal platelet aggregation was measured. All the lupin extracts exhibited a significant anti-aggregatory effect (p < 0.0001), while quinoa extracts did not exert this effect compared to control platelets. In conclusion, lupin beans extracts exhibited an anti-aggregatory effect on activated human platelets.

Aspirin in the primary prevention of cardiovascular disease on diabetic patients: Systematic review and meta-analysis

AIMS

The publication of new trials brought additional data to the controversial topic of aspirin use in diabetic patients for primary prevention. Therefore, we aimed to systematically review all randomized controlled trials evaluating the clinical impact of aspirin in this setting.

METHODS

We searched for randomized controlled trials (RCTs) evaluating the impact of aspirin in patients with diabetes in primary prevention, in MEDLINE, EMBASE, CENTRAL (November/2018). The primary outcomes were all-cause mortality and the composite outcome of major adverse cardiovascular events (MACE). A meta-analysis was performed deriving risk ratios (RR) and 95% confidence intervals (CI).

RESULTS

All-cause mortality was not significantly reduced with RR 0.96 (95% CI 0.90-1.03; 7RCT; 27,595 patients). Regarding MACE, there was an 8% risk reduction (RR 0.92, 95% CI 0.84-0.999; I²=0%; 8RCT; 29,814 patients). The risks of major bleeding (RR 1.30, 95% CI 1.10-1.53; 2RCTs, 18,019 patients), and major GI bleeding (RR 1.39, 95% CI 1.08-1.80; 2RCTs, 18,019 patients) were significantly increased. The risks of cardiovascular mortality, myocardial infarction, stroke and amputation were not significantly different from control arm.

CONCLUSIONS

Aspirin use among diabetic patients in primary prevention appears was associated with increased risk of major bleeding, a modest decrease of MACE and lack of mortality benefit.