Prevention and treatment of thromboembolic and ischemic complications associated with endovascular procedures: Part II--Clinical aspects and recommendations

We reviewed the incidence, risk factors, and clinical features of thromboembolic and ischemic events associated with diagnostic cerebral angiography, endovascular treatment of aneurysms using coils or balloons, angioplasty and stent placement to treat extracranial carotid artery stenosis, and embolization of arteriovenous malformations using glue or other embolic agents. We performed a cumulative analysis to determine the frequency and characteristics of these events and a subset analysis (whenever possible) to determine the benefits of various strategies for complication avoidance. Of the 1,547 patients who underwent Guglielmi detachable coil treatment, thromboembolic events were observed for 127 (8.2%), consisting of asymptomatic events for 12 patients, transient ischemic attacks for 29, and strokes for 86. The outcomes for the 86 patients with strokes were categorized as full recovery for 15, good recovery for 27, partial recovery for 19, no recovery for 11, death for 12, and undetermined outcome for 2. Of the 834 patients who underwent carotid angioplasty and stent placement, thromboembolic events were observed for 73 (8.8%), consisting of transient ischemic attacks for 26 patients and strokes for 47. The outcomes for the patients with strokes were categorized as full recovery for 20, good recovery for 15, partial recovery for 6, no recovery for 2, and death for 4. High rates of thromboembolic events were also observed with balloon occlusion of aneurysms (11%) or parent arteries (19%) and carotid angioplasty alone (5.9%). Arteriovenous malformation embolization was associated with an ischemic event/procedure rate of 9.4%. High rates of thromboembolic and ischemic complications, with subsequent morbidity and death, are associated with most endovascular procedures. Further research and the formulation of standard preventive guidelines may help to reduce these risks and improve the overall success of these procedures.     

Factors associated with aneurysm size in patients with subarachnoid hemorrhage: effect of smoking and aneurysm location

OBJECTIVE: Intracranial aneurysm size is an important determinant of risk of rupture and outcome after rupture. Risk factors influencing aneurysm formation and growth are not well defined. In this study, we examined the association between known risk factors for cerebrovascular disease and size of intracranial aneurysms in patients with aneurysmal subarachnoid hemorrhage. METHODS: We analyzed prospectively collected data from the placebo-treated group in a multicenter clinical trial conducted at 54 neurosurgical centers in North America. The presence, location, and size of intracranial aneurysms were determined by review of the admission angiograms. Pertinent information regarding the presence of various cerebrovascular risk factors was collected for each patient. Using logistic regression analysis, we identified independent determinants of aneurysm size from demographic, clinical, and angiographic characteristics of the participants. The impact of aneurysm size on 3-month mortality was analyzed after adjusting for potential confounding factors. RESULTS: For 298 patients admitted with subarachnoid hemorrhage, the ruptured aneurysms were graded as small (<13 mm) in 235 patients (79%) and large (> or =13 mm) in 63 patients (21%). In the logistic regression model, both smoking at any time (odds ratio, 2.2; 95% confidence interval, 1.1-4.5) and middle cerebral artery origin (odds ratio, 2.5; 95% confidence interval, 1.3-4.9) were independently associated with large aneurysms. Neither hypertension, diabetes mellitus, nor alcohol and illicit drug use were associated with large-sized aneurysms. After adjusting for initial Glasgow Coma Scale score and age in the logistic regression model, the presence of large-sized aneurysms was independently associated with 3-month mortality (odds ratio, 2.3; 95% confidence interval, 1.1-4.8). CONCLUSION: Cigarette smoking and middle cerebral artery origin seem to increase the risk for developing large aneurysms in patients predisposed to intracranial aneurysm formation. Further studies are required to investigate the mechanism underlying the association between cigarette smoking and intracranial aneurysm formation.     

Intraplacental Choriocarcinoma Associated with Viable Pregnancy: Pathologic Features and Implications for the Mother and Infant

Choriocarcinoma arising in the placenta, or intraplacental choriocarcinoma, has seldom been reported, particularly in the absence of maternal metastases. Reluctance to diagnose choriocarcinoma in the presence of chorionic villi can delay diagnosis; however, timely diagnosis of choriocarcinoma is prognostically important, both for the mother and infant. We report the clinicopathologic findings in five mothers and infants in whom choriocarcinoma was identified in the placenta. None of the mothers had a history of gestational trophoblastic disease in previous pregnancies. Three placentas were similar with a single small lesion grossly suggesting a small infarct; microscopically these consisted of infarcted areas surrounded by choriocarcinoma. These three mothers were unusual in that none had metastatic choriocarcinoma; two were treated with chemotherapy and remained disease-free; the third was lost to follow-up shortly following delivery. The remaining two mothers had known pulmonary metastases at time of delivery. One of these latter two placentas contained a large marginal lesion microscopically identified as choriocarcinoma. The fifth placenta had rare microscopic foci of choriocarcinoma, and sheets of necrotic choriocarcinoma were identified in “blood clot” submitted with the placenta. In four of the five cases the choriocarcinoma appeared to be arising from otherwise normal chorionic villi, and in no case was there invasion of the villous stroma. All of the infants survived, and none had evidence of choriocarcinoma. These cases support the concept that choriocarcinoma associated with otherwise normal pregnancy arises in the placenta and may be more common than reported. Received August 11, 1997; accepted December 8, 1997.     

Post‐COVID‐19 splenic infarction in a patient with chronic atrial fibrillation: A case report

We describe splenic infarction (SI), an infrequent condition, in an 82‐year‐old COVID‐19 patient with chronic atrial fibrillation (AF). COVID‐19 may cause thrombosis, and AF is a predisposing factor for splenic infarction. Suspicion of SI may be warranted in COVID‐19 patients with abdominal pain, especially if a predisposing factor exists.     

Flexural Performance of Encased Pultruded GFRP I-Beam with High Strength Concrete under Static Loading

There is an interesting potential for the use of GFRP-pultruded profiles in hybrid GFRP-concrete structural elements, either for new constructions or for the rehabilitation of existing structures. This paper provides experimental and numerical investigations on the flexural performance of reinforced concrete (RC) specimens composite with encased pultruded GFRP I-sections. Five simply supported composite beams were tested in this experimental program to investigate the static flexural behavior of encased GFRP beams with high-strength concrete. Besides, the effect of using shear studs to improve the composite interaction between the GFRP beam and concrete as well as the effect of web stiffeners of GFRP were explored. Encasing the GFRP beam with concrete enhanced the peak load by 58.3%. Using shear connectors, web stiffeners, and both improved the peak loads by 100.6%, 97.3%, and 130.8%, respectively. The GFRP beams improved ductility by 21.6% relative to the reference one without the GFRP beam. Moreover, the shear connectors, web stiffeners, and both improved ductility by 185.5%, 119.8%, and 128.4%, respectively, relative to the encased reference beam. Furthermore, a non-linear Finite Element (FE) model was developed and validated by the experimental results to conduct a parametric study to investigate the effect of the concrete compressive strength and tensile strength of the GFRP beam. The developed FE model provided good agreement with the experimental results regarding deformations and damaged patterns.     

Weekly Nowcasting of New COVID-19 Cases Using Past Viral Load Measurements

The rapid spread of the coronavirus disease COVID-19 has imposed clinical and financial burdens on hospitals and governments attempting to provide patients with medical care and implement disease-controlling policies. The transmissibility of the disease was shown to be correlated with the patient’s viral load, which can be measured during testing using the cycle threshold (Ct). Previous models have utilized Ct to forecast the trajectory of the spread, which can provide valuable information to better allocate resources and change policies. However, these models combined other variables specific to medical institutions or came in the form of compartmental models that rely on epidemiological assumptions, all of which could impose prediction uncertainties. In this study, we overcome these limitations using data-driven modeling that utilizes Ct and previous number of cases, two institution-independent variables. We collected three groups of patients (n = 6296, n = 3228, and n = 12,096) from different time periods to train, validate, and independently validate the models. We used three machine learning algorithms and three deep learning algorithms that can model the temporal dynamic behavior of the number of cases. The endpoint was 7-week forward number of cases, and the prediction was evaluated using mean square error (MSE). The sequence-to-sequence model showed the best prediction during validation (MSE = 0.025), while polynomial regression (OLS) and support vector machine regression (SVR) had better performance during independent validation (MSE = 0.1596, and MSE = 0.16754, respectively), which exhibited better generalizability of the latter. The OLS and SVR models were used on a dataset from an external institution and showed promise in predicting COVID-19 incidences across institutions. These models may support clinical and logistic decision-making after prospective validation.     

Role of second-line systemic treatment post-docetaxel in metastatic castrate resistant prostate cancer- current strategies and future directions

Treatment of metastatic castrate resistant prostate cancer (mCRPC) after progression on docetaxel chemotherapy is a challenging clinical scenario with limited availability of treatment options. Re-treatment with docetaxel, either as monotherapy or in combination with other cytotoxics or targeted agents has shown durable responses. However, most docetaxel re-treatment studies have been either retrospective or early phase non-randomised studies which have not formally assessed Quality of life or survival gain with re-treatment. Despite limited evidence for efficacy of mitoxantrone in the second-line, it continues to remain widely used, largely due to lack of available suitable alternatives. Cabazitaxel in combination with prednisolone is the only chemotherapy to have shown a significant survival benefit and receive approval by the U.S. Food and Drug Administration for patients with mCRPC previously treated with a docetaxel-based regimen. Abiraterone acetate has recently demonstrated a significant improvement in survival when compared to placebo in patients with docetaxel-treated mCRPC. This review aims to summarize the current evidence and discuss future strategies for treatment of mCRPC patients following failure of docetaxel chemotherapy.     

Bilateral proximal deep vein thrombosis and COVID‐19 in a patient with absence of inferior vena cava: A case report and review of literature

Bilateral proximal deep vein thrombosis (DVT) in the lower extremities of young patients should raise suspicion over pro‐thrombotic conditions and venous anatomical abnormalities, even in the presence of other precipitating factors, such as viral infection. The authors present a 33‐year‐old man with bilateral DVT and absence of inferior vena cava (AIVC), who also had concurrent COVID‐19, and discuss the management of this patient.