Improved outcome with individualised antifibrinolytic therapy: what is the evidence?

Viscoelastic haemostatic testing (VHT) has been used to determine hyperfibrinolysis and hypofibrinolysis. When modified by addition of tissue plasminogen activator (tPA), VHT has been suggested to assess responses to antifibrinolytic therapy and to estimate the concentration of tranexamic acid in patients undergoing cardiac surgery. Despite some evidence that tPA-modified VHT might allow individualisation of antifibrinolytic therapy, further studies are warranted to prove its clinical benefit for postsurgical bleeding, transfusion of blood products, and thromboembolic events.

Risk Factors Associated With Exclusion of Obese Patients Ischemic Stroke With a History of Smoking From Thrombolysis Therapy.

The objective of this study is to determine risk factors that may contribute to exclusion decision from recombinant tissue plasminogen activator (rtPA) in patients with acute ischemic stroke (AIS) with a combined current or history of smoking and obesity. This study was conducted on data from 5469 patients with AIS collected from a regional stroke registry. Risk factors associated with inclusion or exclusion from rtPA were determined using multivariate logistic regression analysis. The adjusted odds ratios and 95% confidence interval for each risk factor were used to predict the increasing odds of an association of a specific risk factor with exclusion from rtPA. In the adjusted analysis, obese patients with AIS with a history of smoking (current and previous) excluded from rtPA were more likely to present with carotid artery stenosis (OR = 0.069, 95% CI 0.011-0.442), diabetes (OR = 0.604, 95% CI 0.366-0.997), higher total cholesterol (OR = 0.975, 95% CI 0.956-0.995), and history of alcohol use (OR = 0.438, 95% CI 0.232-0.828). Higher NIHSS score (OR = 1.051, 95% CI 1.017-1.086), higher triglycerides (OR = 1.004, 95% CI 1.001-1.006), and higher high-density lipoprotein (OR = 1.028, 95% CI 1.000-1.057) were associated with the inclusion for rtPA. Our findings reveal specific risk factors that contribute to the exclusion of patients with AIS with a combined effect of smoking and obesity from rtPA. These findings suggest the need to develop management strategies to improve the use of rtPA for obese patients with AIS with a history of smoking.

Preoperative co-application of bevacizumab and tissue plasminogen activator in vitrectomy for proliferative diabetic retinopathy.

PURPOSE: To investigate the clinical benefits of the co-application of bevacizumab and tissue plasminogen activator as adjuncts in the surgical treatment of proliferative diabetic retinopathy. METHODS: Patients who underwent vitrectomy for proliferative dia-betic retinopathy complications were preoperatively given in-travitreal injection with either bevacizumab and tissue plasminogen activator (Group 1) or bevacizumab alone (Group 2). Primary outcomes were surgery time and number of intraoperative iatrogenic retinal breaks. Secondary outcomes included changes in the best-corrected visual acuity and postoperative complications at 3 months postoperatively. RESULTS: The mean surgery time in Group 1 (52.95 ± 5.90 min) was significantly shorter than that in Group 2 (79.61 ± 12.63 min) (p<0.001). The mean number of iatrogenic retinal breaks was 0.50 ± 0.59 (0-2) in Group 1 and 2.00 ± 0.83 (0-3) in Group 2 (p<0.001). The best-corrected visual acuity significantly improved in both groups (p<0.001). One eye in each group developed retinal detachment. CONCLUSION: Preoperative co-application of bevacizumab and tissue plasminogen activator as adjuncts in the surgical treatment of proliferative diabetic retinopathy shortens the surgery time and reduces the number of intraoperative iatrogenic retinal breaks.

Dysregulated hemostasis in acute promyelocytic leukemia.

Acute promyelocytic leukemia (APL) is associated with a high incidence of early death, which occurs within 30 days of diagnosis. The major cause of early death in APL is severe bleeding, particularly intracranial bleeding. Although APL is known to be associated with activation of coagulation, hyperfibrinolysis, and thrombocytopenia, the precise mechanisms that cause bleeding have not yet been elucidated. I propose that a combination of four pathways may contribute to bleeding in APL: (1) tissue factor, (2) the urokinase plasminogen activator/urokinase plasminogen activator receptor, (3) the annexin A2/S100A100/tissue plasminogen activator, and (4) the podoplanin/C-type lectin-like receptor 2. A better understanding of these pathways will identify new biomarkers to determine which APL patients are at high risk of bleeding and allow the development of new treatments for APL-associated bleeding.

Association Between Hematoma Volume and Risk of Subsequent Ischemic Stroke: A MISTIE III and ATACH-2 Analysis.

BACKGROUND: Nontraumatic intracerebral hemorrhage (ICH) is independently associated with a long-term increased risk of major arterial ischemic events. While the relationship between ICH location and ischemic risk has been studied, whether hematoma volume influences this risk is poorly understood. METHODS: We pooled individual patient data from the MISTIE III (Minimally Invasive Surgery Plus Alteplase for Intracerebral Hemorrhage Evacuation Phase 3) and the ATACH-2 (Antihypertensive Treatment of Acute Cerebral Hemorrhage-2) trials. The exposure was hematoma volume, treated as a continuous measure in the primary analysis, and dichotomized by the median in the secondary analyses. The outcome was a symptomatic, clinically overt ischemic stroke, adjudicated centrally within each trial. We evaluated the association between hematoma volume and the risk of an ischemic stroke using Cox regression analyses after adjustment for demographics, vascular comorbidities, and ICH characteristics. RESULTS: Of 1470 patients with ICH, the mean age was 61.7 (SD, 12.8) years, and 574 (38.3%) were female. The median hematoma volume was 17.3 mL (interquartile range, 7.2-35.7). During a median follow-up of 107 days (interquartile range, 91-140), a total of 30 ischemic strokes occurred, of which 22 were in patients with a median ICH volume of ≥17.3 mL and a cumulative incidence of 4.6% (95% CI, 3.1-7.1). Among patients with a median ICH volume <17.3 mL, there were 8 ischemic strokes with a cumulative incidence of 3.1% (95% CI, 1.7-6.0). In primary analyses using adjusted Cox regression models, ICH volume was associated with an increased risk of ischemic stroke (hazard ratio, 1.02 per mL increase [95% CI, 1.01-1.04]). In secondary analyses, ICH volume of ≥17.3 mL was associated with an increased risk of ischemic stroke (hazard ratio, 2.5 [95% CI, 1.1-7.2]), compared with those with an ICH volume <17.3 mL. CONCLUSIONS: In a heterogeneous cohort of patients with ICH, initial hematoma volume was associated with a heightened short-term risk of ischemic stroke.

Retinal arterial and vein occlusion: is surgery ever indicated?

PURPOSE OF REVIEW: To highlight the recent progression in surgical treatments for central retinal vein occlusion (CRVO) and central retinal artery occlusion (CRAO). RECENT FINDINGS: Anti-VEGF treatment, accepted as a primary treatment for CRVO, is unable to effectively treat all types of the diseases. Regarding CRAO, there are not any accepted therapies available. There have however been recent innovations in surgery, such as utilizing robotics-assisted tools in cannulation procedures for central retinal artery occlusion, or micro-cystotomy for refractory macular edema resulting from ischemic CRVO. SUMMARY: Refractory macular edema due to CRVO can be treated with aspiration of the fluid found inside the large cysts often seen in edema. The success rate of micro-cystotomy has been reported at 78% in eyes with refractory macular edema. Recent studies have shown that cannulation with tissue plasminogen activator (tPA) is effective for eyes with CRAO due to thrombus.Recent cannulation or micro-cystotomy procedures can be enhanced with the use of robotic tools which allow us to perform this difficult procedure more easily. Newly developed technology, and consequent developments in surgical procedures, will allow us to deal with unmet needs for retinal vessel occlusive diseases.

Effect of rt-PA on Shear Wave Mechanical Assessment and Quantitative Ultrasound Properties of Blood Clot Kinetics In Vitro.

OBJECTIVE: The consequences associated with blood clots are numerous and are responsible for many deaths worldwide. The assessment of treatment efficacy is necessary for patient follow-up and to detect treatment-resistant patients. The aim of this study was to characterize the effect of treatment on blood clots in vitro using quantitative ultrasound parameters. METHODS: Blood from 10 pigs was collected to form three clots per pig in gelatin phantoms. Clots were subjected to 1) no treatment, 2) rt-PA (recombinant tissue plasminogen activator) treatment after 20 minutes of clotting, and 3) rt-PA treatment after 60 minutes of clotting. Clots were weighted before and after the experiment to assess the treatment effect by the mass loss. The clot kinetics was studied over 100 minutes using elastography (Young's modulus, shear wave dispersion, and shear wave attenuation). Homodyne K-distribution (HKD) parameters derived from speckle statistics were also studied during clot formation and dissolving (diffuse-to-total signal power ratio and intensity parameters). RESULTS: Treated clots loosed significantly more mass than non-treated ones (P < .005). A significant increase in Young's modulus was observed over time (P < .001), and significant reductions were seen for treated clots at 20 or 60 minutes compared with untreated ones (P < .001). The shear wave dispersion differed for treated clots at 60 minutes versus no treatments (P < .001). The shear wave attenuation decreased over time (P < .001), and was different for clots treated at 20 minutes versus no treatments (P < .031). The HKD intensity parameter varied over time (P < .032), and was lower for clots treated at 20 and 60 minutes than those untreated (P < .001 and P < .02). CONCLUSION: The effect of rt-PA treatment could be confirmed by a decrease in Young's modulus and HKD intensity parameter. The shear wave dispersion and shear wave attenuation were sensitive to late and early treatments, respectively. The Young's modulus, shear wave attenuation, and HKD intensity parameter varied over time despite treatment.

Performance comparison of stress hyperglycemia ratio for predicting fatal outcomes in patients with thrombolyzed acute ischemic stroke.

BACKGROUND: The stress hyperglycemia ratio (SHR), a newly developed metric, is used to assess adverse outcomes in patients with acute ischemic stroke (AIS). However, the relationship between SHR and fatal outcomes (in-hospital mortality [IHM], malignant cerebral edema [MCE], symptomatic intracerebral hemorrhage [sICH], 3-month mortality, and poor functional outcome) in AIS patients receiving recombinant tissue plasminogen activator (rt-PA) treatment is unclear, and determining the optimal threshold remains incomplete. MATERIALS AND METHODS: We retrospectively enrolled a total of 345 AIS patients treated with rt-PA during 2015-2022 and collected data on various glucose metrics, including different types of SHR, glycemic gap (GG), random plasma glucose (RPG), fasting plasma glucose (FPG), and hemoglobin A1c (HbA1c). SHR and GG were calculated using these equations: SHR1, [FPG]/[HbA1c]; SHR2, [admission RPG]/[HbA1c]; SHR3, FPG/[(1.59 × HbA1c)-2.59]; SHR4, [admission RPG]/[(1.59 × HbA1c)-2.59]; GG, admission RPG - [(1.59 × HbA1c)-2.59]. We used multivariable logistic regression analysis (MVLR) to identify the association between different glucose metrics and outcomes while comparing their predictive values. RESULTS: SHR1 had the greatest predictive power and a more significant correlation with fatal outcomes than other continuous glucose metrics. The area under the curve of the SHR1 for IHM, MCE, and sICH, 3-month mortality, and poor functional outcome were 0.75, 0.77, 0.77, 0.76, and 0.73, respectively. SHR1 (per 1-point increases) was independently associated with IHM (Odds ratios [ORs] = 5.80; 95% CI [1.96, 17.17]; p = 0.001), MCE (ORs = 4.73; 95% CI [1.71, 13.04]; p = 0.003), sICH (ORs = 4.68, 95% CI [1.48-14.82]; p = 0.009), 3-month mortality (ORs = 10.87; 95% CI [3.56, 33.21]; p<0.001), and 3-month poor functional outcome (ORs = 8.05; 95% CI [2.77, 23.39]; p<0.001) after adjustment in MVLR. In subgroup analysis, elevated SHR1 was associated with fatal outcomes in patients with non-diabetes, SBP≥ 180 mmHg, and NIHSS <16. CONCLUSION: SHR1 demonstrates an independent association with fatal outcomes in AIS patients treated with rt-PA, exhibiting superior predictive ability over other glucose metrics.

Association of IL-6 rs1800795, but not TNF-α rs1800629, and IL-1ß rs16944 polymorphisms' genotypes with recovery of ischemic stroke patients following thrombolysis.

OBJECTIVES: Inflammatory cytokines like tumor necrosis factor-α (TNF-α), interleukin (IL)-1ß, and IL-6 can cause brain injury, slow recovery, and adverse effects (ADEs) in ischemic stroke (IS) patients treated with recombinant tissue plasminogen activator (rtPA). We explored the relationship between selected polymorphisms within TNF-α, IL-1ß and IL-6 genes, and post-IS outcome and ADEs in patients treated with rtPA. METHODS: One hundred and sixty-six patients with IS treated with rtPA were included in this study. The modified Rankin Scale (mRS) was used to assess functional recovery 3 months after IS likewise thrombolytic therapy efficacy. Patients were classified into groups with favorable (0-1) or poor recovery based on their mRS score at the ninetieth day post-IS. During hospitalization, ADEs following rtPA were monitored. TNF-α-308 G/A (rs1800629), IL-1ß-511 G/A (rs16944), and IL-6-174 G/C (rs1800795) polymorphisms were genotyped using Real-Time PCR. SPSS software version 22.0 was used for statistical analyses. RESULTS: Patients with the TNF-α-308 G/A GG genotype had a higher mean NIHSS value at admission (12.75 ± 5.176) than those carrying A-allele (10.56 ± 3.979;p = 0.016). Individuals with the CC genotype of the IL-6-174 G/C polymorphism had significantly lower NIHSS scores (8.79 ± 5.053) than those with G-allele (12.06 ± 6.562) 24 hours after rtPA (p = 0.050). Patients with the GG genotype of the IL-6-174 G/C polymorphism had a significantly poorer outcome (p = 0.024; OR = 2.339; 95%CI 1.121-4.880), while patients who were G-allele carriers of the Il-6-174 G/C polymorphism and had the AA genotype of the IL-1ß-511 G/A polymorphism were statistically significantly more likely to experience hemorrhagic transformation (p = 0.046; OR = 2.7273; 95%CI 1.0414-7.1426). CONCLUSION: GG genotype of the IL-6-174 G/C polymorphism is associated with poor recovery after IS treated with rtPA therapy.

Outcomes of Pleural Space Infections in Patients With Indwelling Pleural Catheters for Active Malignancies.

BACKGROUND: Pleural infections related to indwelling pleural catheters (IPCs) are an uncommon clinical problem. However, management decisions can be complex for patients with active malignancies due to their comorbidities and limited life expectancies. There are limited studies on the management of IPC-related infections, including whether to remove the IPC or use intrapleural fibrinolytics. METHODS: We conducted a retrospective cohort study of patients with active malignancies and IPC-related empyemas at our institution between January 1, 2005 and May 31, 2021. The primary outcome was to evaluate clinical outcomes in patients with malignant pleural effusions and IPC-related empyemas treated with intrapleural tissue plasminogen activator (tPA) and deoxyribonuclease (DNase) compared with those treated with tPA alone or no intrapleural fibrinolytic therapy. The secondary outcome evaluated was the incidence of bleeding complications. RESULTS: We identified 69 patients with a malignant pleural effusion and an IPC-related empyema. Twenty patients received tPA/DNase, 9 received tPA alone, and 40 were managed without fibrinolytics. Those treated with fibrinolytics were more likely to have their IPCs removed as part of the initial management strategy ( P =0.004). The rate of surgical intervention and mortality attributable to the empyema were not significantly different between treatment groups. There were no bleeding events in any group. CONCLUSION: In patients with IPC-related empyemas, we did not find significant differences in the rates of surgical intervention, empyema-related mortality, or bleeding complications in those treated with intrapleural tPA/DNase, tPA alone, or no fibrinolytics. More patients who received intrapleural fibrinolytics had their IPCs removed, which may have been due to selection bias.

[Initial Treatment for Cerebral Infarction].

The treatment protocol for ischemic stroke has changed drastically in the past 20 years. In particular, the indications for recombinant tissue plasminogen activator(rt-PA)and thrombectomy have expanded. Using rt-PA or thrombectomy may be selected smoothly by receiving a call from the emergency team and efficiently collecting patient information, computed tomography scans, and blood samples. The total time required to prepare the equipment and devices should be reduced. To save as many patients as possible, a system should be established. A multidisciplinary approach is necessary from delivery to treatment to overcome the limitations of an individual doctor. Herein, we present our hospital's innovations to help other hospitals develop such systems.

Treatments for Acute Nonarteritic Central Retinal Artery Occlusion: Findings From a Cochrane Systematic Review.

Many interventions for nonarteritic central retinal artery occlusion (CRAO) are associated with serious complications and little effect on visual outcomes. We report on the findings of a Cochrane systematic review that searched seven databases for peer-reviewed articles reporting on treatments for acute nonarteritic CRAO. We assessed six randomized controlled trials, including interventions such as tissue plasminogen activator (t-PA), isovolumic hemodilution, eyeball massage, intraocular pressure reduction, anticoagulation, vasodilation, oxygen inhalation, laser embolysis, transcorneal electrical stimulation, thrombolysis, pentoxifylline, and enhanced external counterpulsation. However, none of the randomized controlled trials demonstrated significant improvement in visual acuity at 1 month compared to observation, and some patients treated with t-PA experienced serious adverse effects including intracranial hemorrhage. Proposed interventions for acute nonarteritic CRAO may not be better than observation, but the evidence is uncertain. Larger, well-designed studies are necessary to determine the most effective management option for acute nonarteritic CRAO. [Ophthalmic Surg Lasers Imaging Retina 2023;54:650-653.].

Current Management of Subretinal Hemorrhage in Neovascular Age-Related Macular Degeneration.

Age-related macular degeneration (AMD) is the leading cause of irreversible vision loss among individuals aged 65 years and older in the USA. For individuals diagnosed with AMD, approximately 12% experience varying levels of subretinal hemorrhage (SRH), which can be further classified by size into small, medium, and massive measured in disc diameters. SRH is an acute and rare sight-threatening complication characterized by an accumulation of blood under the retina arising from the choroidal or retinal circulation. Released iron toxins, reduced nutrient supply, fibrin meshwork contraction, and outer retinal shear forces created by SRH contribute to visual loss, macular scarring, and photoreceptor damage. SRH treatment strategies aim to displace hemorrhage from the foveal region and prevent further bleeding. Although there are no standardized treatment protocols for SRH, several surgical and nonsurgical therapeutical approaches may be employed. The most common surgical approaches that have been utilized are pars plana vitrectomy (PPV) combined with multiple maneuvers such as the removal of choroidal neovascularization lesions, macular translocation, retinal pigment epithelium patch repair, SRH drainage, intravitreal injection of recombinant-tissue plasminogen activator (tPA), expansile gas and air displacement, and anti-vascular endothelial growth factor (anti-VEGF) injections. Nonsurgical therapeutical approaches include intravitreal anti-VEGF monotherapy, intravitreal tPA administration without PPV, and photodynamic therapy. This review article aims to explore the current treatment strategies and supporting literature regarding both surgical and nonsurgical, of SRH in patients with AMD. Moreover, this article also aims to highlight the distinct treatment modalities corresponding to different sizes of SRH.

Minimally Invasive Surgery With Thrombolysis for Intracerebral Hemorrhage Evacuation: Bayesian Reanalysis of a Randomized Controlled Trial.

BACKGROUND AND OBJECTIVES: Bayesian analysis of randomized controlled trials (RCTs) can extend the value of trial data beyond interpretations based on conventional p value-based binary cutoffs. We conducted an exploratory post hoc Bayesian reanalysis of the minimally invasive surgery with thrombolysis for intracerebral hemorrhage (ICH) evacuation (MISTIE-3) trial and derived probabilities of potential intervention effect on functional and survival outcomes. METHODS: MISTIE-3 was a multicenter phase 3 RCT designed to evaluate the efficacy and safety of the MISTIE intervention. Five hundred and six adults (18 years or older) with spontaneous, nontraumatic, supratentorial ICH of ≥30 mL were randomized to receive either the MISTIE intervention (n = 255) or standard medical care (n = 251). We provide Bayesian-derived estimates of the effect of the MISTIE intervention on achieving a good 365-day modified Rankin Scale score (mRS score 0-3) as relative risk (RR) and absolute risk difference (ARD), and the probabilities that these treatment effects are greater than prespecified thresholds. We used 2 sets of prior distributions: (1) reference priors, including minimally informative, enthusiastic, and skeptical priors, and (2) data-derived prior distribution, using a hierarchical random effects model. We additionally evaluated the potential effects of the MISTIE intervention on 180-day and 30-day mRS and 365-, 180-, and 30-day mortality using data-derived priors. RESULTS: The Bayesian-derived probability that MISTIE intervention has any beneficial effect (RR >1) on achieving a good 365-day mRS score was 70% using minimally informative prior, 87% with enthusiastic prior, 68% with skeptical prior, and 73% with data-derived prior. However, these probabilities were ≤55% for RR >1.10 and 0% for RR >1.52 across a range of priors. The probabilities of achieving RR >1 for 180- and 30-day mRS scores are 65% and 80%, respectively. Furthermore, the probabilities of achieving RR <1 for 365-, 180-, and 30-day mortality are 93%, 98%, and 99%, respectively. DISCUSSION: Our exploratory analyses indicate that across a range of priors, the Bayesian-derived probability of MISTIE intervention having any beneficial effect on 365-day mRS for patients with ICH is between 68% and 87%. These analyses do not change the frequentist-based interpretation of the trial. However, unlike the frequentist p values, which indirectly evaluate treatment effects and only provide an arbitrary binary cutoff (such as 0.05), the Bayesian framework directly estimates the probabilities of potential treatment effects. TRIAL REGISTRATION INFORMATION: ClinicalTrials.gov/ct2/show/NCT01827046. CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that minimally invasive surgery (MIS) + recombinant tissue plasminogen activator (rt-PA) does not significantly improve functional outcome in patients with ICH. However, this study lacks the precision to exclude a potential benefit of MIS + rt-PA.

Combined intrapleural alteplase and DNase therapy in complicated pleural infection arising from postsurgery oesophageal leak.

Managing a complicated pleural infection related to postsurgery can pose a clinical challenge, especially when initial interventions such as intercostal chest drain and antibiotics prove ineffective. We describe a man in his mid-60s who developed a recurrence of exudative pleural effusion caused by an oesophageal leak following laparoscopic total gastrectomy with Roux-y oesophagojejunostomy for gastric adenocarcinoma. Surgical repairs and oesophageal stenting were performed to address the oesophageal leak. Despite attempts at intercostal chest tube drainage, ultrasonography-guided targeted drainage of the locule and antibiotics, he did not show any improvement. He was unfit for surgical decortication. Due to the risk of bleeding, we chose a modified dose of intrapleural alteplase 5 mg and DNase 5 mg at 12-hour intervals for a total of three doses. This led to the complete resolution of the effusion. This case highlights that intrapleural tPA/DNase can be an adjunctive therapy in postsurgery-related complicated pleural effusion.

A Successful Treatment Approach in 2 Patients With Type 1 Plasminogen Deficiency: Intratracheal Application of Fresh Frozen Plasma and Tissue Plasminogen Activator.

BACKGROUND: Respiratory system involvement is common in congenital plasminogen deficiency. Although many treatment approaches have been tried, there is still no definitive treatment for respiratory system involvement. OBSERVATIONS: We report 2 congenital plasminogen deficiency cases, who presented with severe respiratory symptoms, for whom a novel treatment modality was tried. After intravenous administration of FFP (fresh frozen plasma), tissue plasminogen activator and FFP were administered intratracheally, and respiratory system findings improved. CONCLUSIONS: Intratracheal administration of tissue plasminogen activator and FFP is an available treatment modality for patients with lung involvement. Fibrin plaques should be carefully removed and new lesion formation should be prevented.

The Role of Subretinal Injection in Ophthalmic Surgery: Therapeutic Agent Delivery and Other Indications.

Subretinal injection is performed in vitreoretinal surgery with two main aims, namely, the subretinal delivery of therapeutic agents and subretinal injection of fluid to induce a controlled and localized macular detachment. The growing interest in this technique is mainly related to its suitability to deliver gene therapy in direct contact with target tissues. However, subretinal injection has been also used for the surgical management of submacular hemorrhage through the subretinal delivery of tissue plasminogen activator, and for the repair of full-thickness macular holes, in particular refractory ones. In the light of the increasing importance of this maneuver in vitreoretinal surgery as well as of the lack of a standardized surgical approach, we conducted a comprehensive overview on the current indications for subretinal injection, surgical technique with the available variations, and the potential complications.

Fibrinolytic and antibiotic treatment of prosthetic vascular graft infections in a novel rat model.

OBJECTIVES: We developed a rat model of prosthetic vascular graft infection to assess, whether the fibrinolytic tissue plasminogen activator (tPA) could increase the efficacy of antibiotic therapy. MATERIALS AND METHODS: Rats were implanted a polyethylene graft in the common carotid artery, pre-inoculated with approx. 6 log10 colony forming units (CFU) of methicillin resistant Staphylococcus aureus. Ten days after surgery, rats were randomized to either: 0.9% NaCl (n = 8), vancomycin (n = 8), vancomycin + tPA (n = 8), vancomycin + rifampicin (n = 18) or vancomycin + rifampicin + tPA (n = 18). Treatment duration was seven days. Approximately 36 hours after the end of treatment, the rats were euthanized, and grafts and organs were harvested for CFU enumeration. RESULTS: All animals in the control group had significantly higher CFU at the time of euthanization compared to bacterial load found on the grafts prior to inoculation (6.45 vs. 4.36 mean log10 CFU/mL, p = 0.0011), and both the procedure and infection were well tolerated. Vancomycin and rifampicin treatment were superior to monotherapy with vancomycin, as it lead to a marked decrease in median bacterial load on the grafts (3.50 vs. 6.56 log10 CFU/mL, p = 0.0016). The addition of tPA to vancomycin and rifampicin combination treatment did not show a further decrease in bacterial load (4.078 vs. 3.50 log10 CFU/mL, p = 0.26). The cure rate was 16% in the vancomycin + rifampicin group vs. 37.5% cure rate in the vancomycin + rifampicin + tPA group. Whilst interesting, this trend was not significant at our sample size (p = 0.24). CONCLUSION: We developed the first functional model of an arterial prosthetic vascular graft infection in rats. Antibiotic combination therapy with vancomycin and rifampicin was superior to vancomycin monotherapy, and the addition of tPA did not significantly reduce bacterial load, nor significantly increase cure rate.

Visual Recovery and Prognosis in the Treatment of Submacular Hemorrhage due to Polypoidal Choroidal Vasculopathy and Retinal Arterial Macroaneurysm: A Retrospective Study.

Purpose: This study was carried out to evaluate the visual acuity (VA), complications, and prognosis of patients diagnosed with submacular hemorrhage (SMH) from polypoidal choroidal vasculopathy (PCV) and retinal arterial macroaneurysm (RAM) treated by pars plana vitrectomy (PPV), subretinal tissue plasminogen activator (tPA), and air tamponade in vitreous cavity. It facilitates the development of generic treatment methods that can be widely used to improve vision and treat potential complications in patients with SMH, regardless of the underlying pathophysiological condition, such as PCV or RAM. Methods: In this retrospective study, SMH patients were divided into two groups based on their diagnosis: (1) polypoidal choroidal vasculopathy (PCV) and (2) retinal arterial macroaneurysm (RAM). The visual recovery and complications of patients with PCV and RAM after PPV + tPA (subretinal) surgery were analyzed. Results: A total of 36 eyes of 36 patients were included: PCV (47.22%, 17/36) and RAM (52.78%, 19/36). The mean age of the patients was 64 years, and 63.89% of the patients (23/36) were female. The median VA was 1.85 logMAR before surgery, 0.93 and 0.98 logMAR at 1 and 3 months after surgery, respectively, indicating that most patients' vision improved after surgery. At the 1 and 3 months postoperative follow-up, each patient was diagnosed with rhegmatogenous retinal detachment at 1 month and 3 months postoperatively, and four patients had vitreous hemorrhage at 3 months postoperatively. Preoperatively, patients exhibited macular subretinal hemorrhage, retinal bulge, and exudation around the blood clot. Postoperatively, most patients showed dispersal of subretinal hemorrhage. Optical coherence tomography results revealed retinal hemorrhage involving the macula and hemorrhagic bulges under both the neuroepithelium and the pigment epithelium under the fovea preoperatively. After surgery, the air injected into the vitreous cavity was completely absorbed and the subretinal hemorrhage was dispersed. Conclusion: PPV combined with subretinal tPA injection and air tamponade in the vitreous cavity can facilitate modest visual recovery in patients with SMH due to PCV and RAM. However, some complications may occur, and their management remains challenging.