Early Postmarket Results with EmboTrap II Stent Retriever for Mechanical Thrombectomy: A Multicenter Experience

BACKGROUND AND PURPOSE

EmboTrap II is a novel stent retriever with a dual-layer design and distal mesh designed for acute ischemic stroke emergent large-vessel occlusions. We present the first postmarket prospective multicenter experience with the EmboTrap II stent retriever.

MATERIALS AND METHODS

A prospective registry of patients treated with EmboTrap II at 7 centers following FDA approval was maintained with baseline patient characteristics, treatment details, and clinical/radiographic follow-up.

RESULTS

Seventy patients were treated with EmboTrap II (mean age, 69.9 years; 48.6% women). Intravenous thrombolysis was given in 34.3%, and emergent large-vessel occlusions were located in the ICA (n = 18), M1 (n = 38), M2 or M3 (n = 13), and basilar artery (n = 1). The 5 × 33 mm device was used in 88% of cases. TICI ≥ 2b recanalization was achieved in 95.7% (82.3% in EmboTrap II-only cases), and first-pass efficacy was achieved in 35.7%. The NIHSS score improved from a preoperative average of 16.3 to 12.1 postprocedure and to 10.5 at discharge. An average of 2.5 [SD, 1.8] passes was recorded per treatment, including non-EmboTrap attempts. Definitive treatment was performed with an alternative device (aspiration or stent retriever) in 9 cases (12.9%). Some hemorrhagic conversion was noted in 22.9% of cases, of which 4.3% were symptomatic. There were no device-related complications.

CONCLUSIONS

Initial postmarket results with the EmboTrap II stent retriever are favorable and comparable with those of other commercially available stent retrievers. Compared with EmboTrap II, the first-generation EmboTrap may have a higher first-pass efficacy; however, data are limited by retrospective case analysis, incomplete clinical follow-up, and small sample size, necessitating future trials.

Applications of a Novel Microangioscope for Neuroendovascular Intervention

BACKGROUND AND PURPOSE

Visualization in neuroendovascular intervention currently relies on biplanar fluoroscopy and contrast administration. With the advent of endoscopy, direct visualization of the intracranial intravascular space has become possible with microangioscopes. We analyzed the efficacy of our novel microangioscope to enable direct observation and inspection of the cerebrovasculature, complementary to a standard fluoroscopic technique.

MATERIALS AND METHODS

Iterations of microangioscopes were systematically evaluated for use in neurodiagnostics and neurointerventions in both live animal and human cadaveric models. Imaging quality, trackability, and navigability were assessed. Diagnostic procedures assessed included clot identification and differentiation, plaque identification, inspection for vessel wall injury, and assessment of stent apposition. Interventions performed included angioscope-assisted stent-retriever thrombectomy, clot aspiration, and coil embolization.

RESULTS

The microangioscope was found helpful in both diagnosis and interventions by independent evaluators. Mean ratings of the imaging quality on a 5-point scale ranged from 3.0 (clot identification) to 4.7 (Pipeline follow-up). Mean ratings for clinical utility ranged from 3.0 (aspiration thrombectomy) to 4.7 (aneurysm treatment by coil embolization and WEB device).

CONCLUSIONS

This fiber optic microangioscope can safely navigate and visualize the intravascular space in human cadaveric and in vivo animal models with satisfactory resolution. It has potential value in diagnostic and neurointerventional applications.

QTc: how long is too long?

Congenital long QT syndrome (LQTS) affects an estimated 1 in 2500 people and typically presents with syncope, seizures or sudden death. Whereas someone exhibiting marked prolongation of the QT interval with QTc exceeding 500 ms who was just externally defibrillated from torsades de pointes while swimming poses negligible diagnostic challenge as to the unequivocal probability of LQTS, the certainty is considerably less for the otherwise asymptomatic person who happens to host a QTc value coined "borderline" (QTc > or = 440 ms). Although a normal QT interval imparts a much lower risk of life-threatening events, it does not preclude a patient from nevertheless harbouring a potentially lethal LQTS-causing genetic mutation. Indeed, genetic testing exerts significant diagnostic, prognostic and therapeutic implications. However, the 12-lead ECG remains the universal initial diagnostic test in the evaluation of LQTS and is subject to miscalculation, misinterpretation and mishandling. This review discusses the components of accurate QTc measurement and diagnosis, re-examines what is known about factors affecting QT interval measurement, and clarifies current recommendations regarding diagnosis of so-called "borderline" QT interval prolongation. The current guideline recommendations for the athlete with LQTS are also summarised.

Identification of a possible pathogenic link between congenital long QT syndrome and epilepsy

BACKGROUND

Long QT syndrome (LQTS) typically presents with syncope, seizures, or sudden death. Patients with LQTS have been misdiagnosed with a seizure disorder or epilepsy and treated with antiepileptic drug (AED) medication. The gene, KCNH2, responsible for type 2 LQTS (LQT2), was cloned originally from the hippocampus and encodes a potassium channel active in hippocampal astrocytes. We sought to test the hypothesis that a "seizure phenotype" was ascribed more commonly to patients with LQT2.

METHODS

Charts were reviewed for 343 consecutive, unrelated patients (232 females, average age at diagnosis 27 +/- 18 years, QTc 471 +/- 57 msec) clinically evaluated and genetically tested for LQTS from 1998 to 2006 at two large LQTS referral centers. A positive seizure phenotype was defined as the presence of either a personal or family history of seizures or history of AED therapy.

RESULTS

A seizure phenotype was recorded in 98/343 (29%) probands. A seizure phenotype was more common in LQT2 (36/77, 47%) than LQT1 (16/72, 22%, p < 0.002) and LQT3 (7/28, 25%, p < 0.05, NS). LQT1 and LQT3 combined cohorts did not differ significantly from expected, background rates of a seizure phenotype. A personal history of seizures was more common in LQT2 (30/77, 39%) than all other subtypes of LQTS (11/106, 10%, p < 0.001).

CONCLUSIONS

A diagnostic consideration of epilepsy and treatment with antiepileptic drug medications was more common in patients with LQT2. Like noncardiac organ phenotypes observed in other LQTS-susceptibility genes such as KCNQ1/deafness and SCN5A/gastrointestinal symptoms, this novel LQT2-epilepsy association raises the possibility that LQT2-causing perturbations in the KCNH2-encoded potassium channel may confer susceptibility for recurrent seizure activity.

Nanosecond freezing of water under multiple shock wave compression: continuum modeling and wave profile measurements

Using real time optical transmission and imaging measurements in multiple shock wave compression experiments, water was shown to solidify on nanosecond time scales [D. H. Dolan and Y. M. Gupta, J. Chem. Phys. 121, 9050 (2004)]. Continuum modeling and wave profile measurements, presented here, provide a complementary approach to examine the freezing of shocked water. The water model consisted of thermodynamically consistent descriptions of liquid and solid (ice VII) water, relationships for phase coexistence, and a time-dependent transition description to simulate freezing dynamics. Continuum calculations using the water model demonstrate that, unlike single shock compression, multiple shock compression results in pressure-temperature conditions where the ice VIII phase is thermodynamically favored over the liquid phase. Wave profile measurements, using laser interferometry, were obtained with quartz and sapphire windows at a peak pressure of 5 GPa. For water confined between sapphire windows, numerical simulations corresponding to a purely liquid response are in excellent agreement with the measured wave profile. For water confined between quartz windows (to provide a nucleating surface), wave profile measurements demonstrate a pure liquid response for an incubation time of approximately 100 ns followed by a time-dependent transformation. Analysis of the wave profiles after the onset of transformation suggests that water changes from a metastable liquid to a denser phase, consistent with the formation of a high-pressure ice phase. Continuum analyses and simulations underscore the need for multiple time scales to model the freezing transition. Findings from the present continuum work are extremely consistent with optical results reported previously. These studies constitute the first comprehensive investigation reported for freezing of a liquid at very short time scales.

Prevalence of glucose intolerance in primary hyperparathyroidism and the benefit of parathyroidectomy

BACKGROUND

Increased prevalence of diabetes mellitus (DM) in primary hyperparathyroidism (PHPT) is established, but not glucose intolerance (GI), nor benefit from parathyroidectomy on GI. We determined these during management of a continuous series of patients with PHPT routinely followed after surgery.

PATIENTS AND METHODS

WHO criteria classified 75 g oral glucose tolerance tests (OGTT) in 51/54 consecutively proven PHPT patients, into normal glucose tolerance (NGT), DM, impaired glucose tolerance (IGT) or impaired fasting glucose (IFG); GI was derived by adding those with DM and IGT/IFG. OGTT were repeated after parathyroidectomy (mean follow up 2.4 +/- SD 1.6 years). Paired student t tests were used to compare fasting and 2-h plasma glucose (PG).

RESULTS

At presentation 32/54 patients (59%) had NGT, 10 IGT/IFG (19%) and 12 type 2 DM (22%), nine newly diagnosed. Before parathyroidectomy 17/35 patients had NGT (49%), 18 GI (51%), 12 DM (34%) and 6 IGT/IFG (17%). Five out of six patients with IGT/IFG had NGT, one with NGT developed IGT. At completion 23 patients (66%) had NGT, 12 GI (34%), 4 IGT/IFG (11%) and 8 DM (23%). After parathyroidectomy fasting and 2-h. PG fell in 30/34 normocalcaemic patients not on hypoglycaemic agents, 5.6 +/- 1.0 to 5.4 +/- 0.8 mmol/l, 7.2 +/- 3.0 to 6.3 +/- 3.1 mmol/l (p < 0.05, p < 0.01).

CONCLUSIONS

1. At presentation with PHPT, OGTT commonly identifies Type 2 DM and GI.2. After successful parathyroidectomy fasting and 2-h. PG fall significantly (p < 0.05, p < 0.01). DM and IGT/IFG often ameliorates to IGT or NGT, persistently.

Comparison of extraperitoneal and transperitoneal methods of aorto-iliac reconstruction. Twenty years experience

The operative technique of extraperitoneal approach to the aorta is described. The results of operation on the aorta using this technique are compared with those using the standard transperitoneal approach.

Effects of propranolol on hepatic haemodynamics in the cirrhotic and non-cirrhotic rat

The effects of systemic and intraportal administration of propranolol on hepatic haemodynamics were studied in cirrhotic and non-cirrhotic rats. In the non-cirrhotic rat systemic infusion of 4 micrograms (kg body wt)-1 min-1 propranolol significantly decreased portal pressure, wedged hepatic venous pressure, portal venous flow and liver blood flow without affecting heart rate. Similar changes were observed in the cirrhotic rat following an infusion of 2 micrograms (kg body wt)-1 min-1 propranolol. Higher rates of propranolol infusion produced greater reductions in portal pressure, wedged hepatic venous pressure, portal venous flow and liver blood flow in cirrhotic and non-cirrhotic rats but these changes were accompanied by a bradycardia. The reduction in portal pressure effected by propranolol was accompanied by an increased splanchnic vascular resistance. Intraportal injection of propranolol resulted in a rapid but transient fall in portal pressure. The decrease in portal pressure was sustained if propranolol was infused intraportally. The results indicate that propranolol effects a reduction in portal pressure via a combination of increased splanchnic vascular resistance, increased hepatic arterial resistance and reduced cardiac output. The observation that propranolol can significantly reduce portal pressure without affecting heart rate may be clinically important in the long-term management of portal hypertension. Furthermore, the rapid reduction in portal pressure following intravenous administration suggests that propranolol may be of value in the acute control of variceal haemorrhage.

The effect of repeated mating at short intervals on reproductive performance of gilts

Three trials involving 87 gilts were completed to investigate the role of additional sexual stimulation on various reproductive parameters. Forty-five gilts were mated twice at 12-h intervals at second pubertal estrus with intact boars beginning 12 h after detection of sexual receptivity (control group). Forty-two gilts were exposed to a vasectomized boar 15 min following each fertile mating to provide additional copulatory stimulus (treatment group). This additional exposure improved (P less than .01) conception rate (100 vs 84%). No statistical differences were observed in number of corpora lutea (CL), number of viable embryos (VE) or number of total embryos (TE) at d 30. These results suggest that additional mating stimuli may have a beneficial effect on conception rate. While the use of additional males resulted in more pregnant females, it likely did not have an effect on litter size.

The effect of povidone-iodine irrigation on perineal wound healing following proctectomy for carcinoma

Fifty-six patients undergoing abdomino-perineal excision of the rectum for carcinoma were randomized to receive twice daily irrigation of the perineal wound with either 1% povidone-iodine (PVP-I) or normal saline for 5 days following surgery. The incidence of perineal wound infection, primary and delayed wound healing and persistent sinus formation was recorded. There was a highly significant reduction in perineal wound infection in the PVP-I group (P less than 0.01) and this was true even if perineal wound contamination had occurred during operation (P less than 0.05). Primary wound healing was significantly improved in the treatment group (P less than 0.02) and this was found also in the presence of contamination (P less than 0.005). There was no significant difference between the treated and control group in the incidence of delayed wound healing and persistent sinus formation.

Herpes zoster and paralytic ileus: a case report

A case of herpes zoster presenting as intestinal obstruction is described. Clinical and radiological evidence of intestinal obstruction was obtained. The mechanisms by which herpes zoster may cause an ileus are discussed.