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PubMed2002

[Interventional therapy of bypass stenoses].

BACKGROUND: Percutaneous balloon angioplasty (PTCA) of lesions in aorto-coronary saphenous vein grafts remains one of the most hazardous procedures in interventional cardiology. It is associated with a high rate of distal embolizations, increased incidence of periprocedural myocardial infarctions and amplified in-hospital and long-term mortality. Moreover, PTCA is complicated by a high rate of restenosis, which did not decline significantly after the implantation of coronary stents. LATEST STRATEGIES IN BYPASS STENOSES: Herein we review the latest advances in PTCA and stent implantation in vein grafts, discuss the impact of new stent designs, temporary antiaggregatory regimes and mechanic embolus protection devices and point towards future directions, which may help to further improve safety and efficacy of percutaneous interventions in this challenging subgroup of lesions.

Angioplasty, Balloon, Coronary↗
PubMed1994

[What's new in cardiopulmonary resuscitation? American Heart Association].

A strong consensus was reached for several changes in the guidelines for cardiopulmonary resuscitation (CPR) and emergency cardiac care (ECC) in the 1992 conference on CPR and ECC held by the Emergency Cardiac Care Committee of the American Heart Association. These new recommendations, together with differing recommendations of the European Resuscitation Council, are described. An unresponsive person with spontaneous respirations should be placed in the recovery position if no cervical trauma is suspected. Compared with endotracheal intubation, other airway-protecting devices such as combination esophageal-tracheal tubes are of minor acceptance. During ventilation, the time for filling the lungs is increased to 1.5-2 s to decrease the likelihood of gastric insufflation. Delivery of i.v. drugs can be enhanced by an i.v. flush of sodium chloride. In endotracheal drug administration, higher doses and drug dilution are recommended. In infants and children up to 6 years of age, the value of intraosseous drug administration is emphasized. For pulseless adult victims, the initial dosage of epinephrine of 1 mg i.v. remains unchanged. For repeat doses, high-dose epinephrine up to 0.1 mg/kg is classified as of uncertain but possible efficacy. For lidocaine, the recommended i.v. dosage is 1.5 mg/kg. Sodium bicarbonate and calcium are not routinely recommended for resuscitation. For atropine, the maximum dose is 0.04 mg/kg. If hypomagnesaemia is present in recurrent and refractory ventricular fibrillation, it should be corrected by administration of 1 to 2 g magnesium sulfate i.v. Thrombolytic agents are classified as useful and effective in acute myocardial infarction and should be administered as early as possible. Glucose-containing fluids are discouraged for resuscitative efforts.

Cardiopulmonary Resuscitation↗
PubMed2003

[HCV, HBV and HIV infections: risk for surgeon and staff. Results and consequences of routine screening in emergency patients].

BACKGROUND: Trauma and emergency surgeons (S) are in contact with high-risk patients (P) infected with HBV, HCV, and HIV without knowing which P is and which is not infected. The aim of this paper was to analyze routine screening (SCR) in trauma care. METHOD: Microparticle enzyme immunoassays (MEIA) (Abbott Axym system) were analyzed from routine blood samples: HBsAg (V2), HCV version 3.0, HIV 1/2gO. All positive or uncertain samples were confirmed with ELISA/PCR. RESULTS: From January 2002 to October 2002 a total of 1074 emergency P were examined. The results were available within 50 min after admittance to the emergency room. In 53 of 1074 (4.9%) the MEIA was positive or in threshold margins (LV): HBV 15 P plus 3 LV (9 secured by ELISA/PCR), prevalence (PV) 0.84%. HCV 34 P plus 1 LV (31 secured with ELISA/PCR), PV 2.9%. HIV 2 P, PV 1.86 per thousand, 1 in co-infection with HCV, 1 with HBV. Of 42 infections, 21 were unknown before screening, and in 5 P the S suspected an infection. After screening, nine surgical procedures were changed to safer procedures. CONCLUSION: MEIA is a good tool for quick SCR of HCV, HBV, and HIV in emergency surgery (ES). When the infection is known the S is more aware to perform only safe procedures during surgery (no touch technique) or to use more protective devices (e.g., fluid shield, double gloves). Our results indicate that surgeons and nurses in ES are exposed four to six times more often to infection with HCV, HBV, and HIV than represented by officially published data. We recommend routine SCR of HBV, HCV, and HIV for all P in ES. Prevention procedures are discussed.

Adolescent↗
PubMed2005

[Stenting in acute stroke].

Hemodynamic impairment caused by pseudo-occlusion or occlusion of the internal carotid artery (ICA) is a rare etiology of stroke. Acute revascularization of the vessel can restore the flow to the brain. This retrospective study shows that ICA stenting with proximal and distal protection devices in patients with acute stroke and pseudo-occlusion or occlusion of the ICA is technically feasible and can prevent further hemodynamic strokes. In contrast, selected patients have a high risk of reperfusion syndrome with intracranial hemorrhage and peri-interventional monitoring of blood pressure in an ICU is recommended.

Acute Disease↗
PubMed2003

Effects of non-invasive ventilation on middle ear function in healthy volunteers.

OBJECTIVES: To evaluate the effects of non-invasive ventilation (NIV) with facial mask or helmet on middle ear (ME). DESIGN. Prospective, randomised study. SETTING: University hospital. PARTICIPANTS: Ten healthy subjects randomly allocated in two groups of five subjects each. INTERVENTIONS: NIV for 1 h, with helmet (group H) or facial mask (group M). Flow-triggered pressure support was 10 cmH(2)O, PEEP 5 cmH(2)O, FiO(2) 0.21. MEASUREMENTS AND RESULTS: Impedenzometry was performed before NIV and 5 min after NIV ended; it was repeated 60 min later. In group H the acoustic compliance increased after NIV from 2.0+/-.6 ml to 2.3+/-.6 ml ( P<.01), suggesting that the tympanic membrane became less stiff; 1 h later the compliance returned to basal values (2.0+/-.7 ml); in group M the compliance was unaffected (from 2.0+/-.5 ml to 2.0+/-.4 ml; 1.9+/-.4 ml 1 h later). The acoustic reflex, i.e., the contraction of the stapedial muscle in response to an auditory stimulus, involving the acoustic and facial nerves, was also evaluated during impedenzometry at 250 Hz, 500 Hz, 1,000 Hz, and 4,000 Hz; no significant change of the threshold was observed. CONCLUSIONS: The tympanic membrane is tighten by the tensor tympani and a reversible loosening suggests muscle fatigue in response to the application of intermittent positive pressure applied to the external ear during NIV with helmet. The loss of tensor tympani protective action could theoretically predispose the middle and inner ear to mechanical damage during NIV with helmet, suggesting the use of protective devices (ear plugs) in selective cases requiring long-term, high-pressure treatment.

Adult↗
PubMed2006

Cognitive changes after carotid artery stenting.

INTRODUCTION: We aimed to test changes in cognitive performance after carotid artery stenting (CAS). METHOD: Ten patients were neuropsychologically tested at least 24 h before and 48 h after CAS. To diminish thromboembolic events, we used a proximal protection device. The following neuropsychological tests were selected: The Mini Mental State Examination (MMSE), symbol digit test and subtests of the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) battery (verbal fluency, constructional practice, word list memory and delayed recall). Affective state was determined by the Beck Depression Score (BDS). RESULTS: No patient suffered from depression (BDS <1) or dementia (MMSE 29.9+/-1.5). Nine of the ten patients (P=0.12) showed increased speed in the Number Connection Test (NCT) (corresponding to trail making test). Most patients showed better or similar results concerning delayed recall (P=0.31). No change was observed in the symbol digit test, word list memory, verbal fluency or constructional practice. Better results concerning NCT and delayed recall after carotid stenting might be due to improved brain perfusion. CONCLUSION: After CAS, cognitive and memory performance seem to improve. Further studies with different time intervals and more refined testing, as well as perfusion-weighted imaging, are needed.

Aged↗
PubMed2007

Carotid angioplasty and stent placement for restenosis after endarterectomy.

INTRODUCTION: Recurrent carotid stenosis following endarterectomy is a common complication, and reoperation may be associated with increased morbidity. The goal of this study was to determine the procedural safety and long-term complication rates of carotid angioplasty and stenting for recurrent stenosis. METHODS: Of 248 consecutive carotid angioplasty and/or stenting procedures performed at our institution between March 1996 and November 2005, 83 procedures for recurrent stenosis following endarterectomy were performed in 75 patients (mean age 68 years; 43 men, 32 women) without cerebral protection devices. The patients' medical records were retrospectively reviewed for vascular imaging reports and available clinical follow-up. Procedural and long-term complication rates were calculated. RESULTS: Recurrent stenosis was reduced from a mean of 80.6% to no significant stenosis in 82 of 83 procedures. The procedural stroke rate was 3 out of 83 procedures (3.6%). The procedural transient ischemic attack (TIA) rate was 2 out of 83 procedures (2.4%). Mean follow-up was 22.4 months (range 0.1 to 86.7 months) with at least 6 months follow-up for 54 of 83 procedures (65%). There were five TIAs and no strokes on follow-up (new TIAs at 25.5 and 43.4 months; recurrent TIAs at 1, 11.1, and 12 months, all with normal angiograms). The composite 30-day stroke, myocardial infarction, or death rate was 5 of 83 procedures (6.0%). CONCLUSION: In this series, angioplasty and stenting were effective in relieving stenosis secondary to recurrent carotid disease after endarterectomy, and have low rates of ischemic complications.

Aged↗
PubMed2001

Teaching hospital perspective of the quality of trauma care in Lagos, Nigeria.

Information including respiratory rate, blood pressure, Glasgow Coma Scale, and anatomic injuries were obtained for all injured patients consecutively admitted to the Lagos University Teaching Hospital (LUTH) during the 9-month period from September 1995 to May 1996. The data were analyzed using the UK Major Trauma Outcome Study (MTOS) methodology. The Revised Trauma Score (RTS), the Injury Severity Score (ISS), and the Probability of Survival (Ps) were calculated for each patient. In addition, the "M," "z," and "w" scores were calculated for blunt injuries. Of the 253 patients (median age 28 years; male/female ratio 4:1) studied, 85% suffered blunt trauma, 75% of which were due to RTA. About 60% of RTA victims were pedestrians. Only 8% of nonpedestrian victims wore protective devices. The mean ISS was 10, the mean RTS 6.98, and the mean Ps 0.96. The "m" statistic for blunt trauma was 0.91, and there were 122 survivors compared to the 163 predicted. The "z" and "w" scores were -18.49 and -24.55, respectively. Altogether, 42.7% of patients with ISS > 15 and 40.7% with RTS < 7.5 died. According to these results, the severity of injuries encountered in Lagos is comparable to those reported from the United Kingdom and the United States, but the death rate is higher.

Adolescent↗
PubMedDate not supplied

Distal embolization after stenting of the vertebral artery: diffusion-weighted magnetic resonance imaging findings.

PURPOSE: We retrospectively evaluated our experience with stenting of the vertebral artery in an effort to determine the risk of distal embolization associated with the procedure. METHODS: Between June 2000 and May 2005, 35 patients with 38 stenting procedures for atherosclerotic disease of the vertebral origin in our institution were identified. The average age of the patients was 60.3 years (range 32-76 years). Sixteen of these patients (with 18 stents) had MR imaging of the brain with diffusion-weighted imaging and an apparent diffusion coefficient map within 2 days before and after procedure. RESULTS: On seven of the 16 postprocedural diffusion-weighted MR images, a total of 57 new hyperintensities were visible. All these lesions were focal in nature. One patient demonstrated a new diffusion-weighted imaging abnormality in the anterior circulation without MR evidence of posterior circulation ischemia. Six of 16 patients had a total of 25 new lesions in the vertebrobasilar circulation in postprocedural diffusion-weighted MR images. One patient in this group was excluded from the final analysis because the procedure was complicated by basilar rupture during tandem stent deployment in the basilar artery. Hence, new diffusion-weighted imaging abnormalities were noted in the vertebrobasilar territory in 5 of 15 patients after 17 stenting procedures, giving a 29% rate of diffusion-weighted imaging abnormalities per procedure. No patient with bilateral stenting had new diffusion-weighted imaging abnormalities. CONCLUSION: Stenting of stenoses of the vertebral artery origin may be associated with a significant risk of asymptomatic distal embolization. Angiography, placement of the guiding catheter, inflation of the stent balloon, and crossing the lesion with guidewires or balloon catheters may potentially cause distal embolization. Further studies to evaluate measures to increase the safety of vertebral artery stenting, such as the use of distal protection devices or short-term postprocedural anticoagulation, should be considered for patients with clear indications for this procedure.

Adult↗
PubMed2003

Predictors of falls in elderly people during rehabilitation after hip fracture--who is at risk of a second one?

BACKGROUND: A fall in old age is known as a common consequence of frailty and decline as well as a risk factor for further falls. Studies identifying hip fracture patients who are at risk of a further fall are lacking. Therefore it was of interest to evaluate the risk factors for falling in a high-risk population, i.e., patients during rehabilitation after recent proximal femur fracture. METHODS: 935 consecutive patients who had surgical intervention after acute fracture of the proximal femur underwent a multidimensional assessment within the first two days after admission to the rehabilitation ward. Falls during the stay on the rehabilitation ward were registered. The baseline data were compared between fallers and non-fallers. FINDINGS: 11.8% of the patients fell during rehabilitation. Risk factors associated with a fall were increasing age, male gender, type of surgery, the use of a rollator and nocturnal urinary incontinence. The risk of falling increased in the middle of the second week of rehabilitation, when frailer patients gained mobility and ability to walk by themselves, while they were not yet safe enough. INTERPRETATION: It was possible to compose a risk profile for future falls. Those identified as 'at risk of a further fall' should be selectively offered protective devices and special training programs in order to prevent future fractures. As for the surgical intervention, the type of surgery in relation to age and long-term outcome is of particular interest since the use of the more expensive total hip arthroplasty procedure may be more cost effective in the long term.

Accidental Falls↗
PubMed2006

Carotid-artery stenting in a high-risk patient population--single centre, single operator results.

AIMS: The aim of this study was to assess the outcome of carotid-artery stenting (CAS) in high-risk patients in routine clinical settings while excluding the impact of multiple operators and the learning curve of individual operators on the outcome, and to determine the impact of individual risk factors, including vascular multimorbidity, on the outcome. METHODS AND RESULTS: A total of 143 consecutive patients, 100 (69.9%) males and 43 (30.1%) females, mean age 68.7+/-8 years treated between February 1999 and May 2004 in the Heart Centre Coswig by a single operator for a symptomatic (n=37) and asymptomatic (n=106) on average greater than 70% (82.3+/-10.7%) or 80% (85.0+/-9.1%) NASCET carotid-artery stenosis, respectively, were studied. At least one NASCET exclusion criteria was present in 140 patients (97.9%), and vascular multimorbidity was present in 94 (65.7%) patients. In 28 (19.6%) patients there was a complete occlusion of the contralateral internal carotid artery and in 12 (8.4%) patients the procedure was performed prior to emergency coronary bypass surgery. In all, 47 (32.9%) procedures were performed without and 96 (67.1%) were performed with thromboembolic protection. Technical success was achieved in all patients. Combined neurological complications, TIA, PRIND and stroke, occurred in 5 (3.5%) patients, of which 3 (2.1%) were PRIND and 2 (1.4%) were strokes. The neurological complications were more frequent and more severe in symptomatic patients compared to asymptomatic patients (PRIND 2.7% vs 1.9%; stroke 0% vs 5.4%). In patients in whom thromboembolic protection was used, the rate of neurological complications was lower compared to those without protection (PRIND 1.0% vs 4.3%; stroke 1.0% vs. 2.1%). There was no death related to the procedure. Neurological complications were more frequent and more severe in patients with vascular multimorbidity compared to those with an isolated carotid-artery stenosis (4.2% vs 2.0%). The rate of neurological complications was similar in type II diabetics and nondiabetics (2.9% vs 4.1%). In 4.2%, minor complications related to the arterial puncture site were observed (3.5% hematoma not requiring blood transfusion, 0.7% pseudoaneurysm). At follow-up after a minimum of 6 months, 9 (6.3%) patients had died, the majority of whom had died of cardiovascular disease (3.5%). CONCLUSIONS: CAS can be performed with an acceptable risk in high-risk patients in routine clinical settings when it is performed by an experienced operator. The use of thromboembolic protection devices reduces the risk of neurological complications. Presence of vascular multimorbidity, but not diabetes, appears to increase the risk of all causes and of neurological complications.

Aged↗
PubMed2005

Risk factors for periprocedural complications in carotid artery stenting without filter protection: A serial diffusion-weighted MRI study.

INTRODUCTION: In high-grade stenosis, carotid artery stenting (CAS) may be chosen as an alternative to carotid surgery. Ischemic periprocedural complications may be documented best with diffusion-weighted MRI (DWMRI). In this prospective study serial DW-MRI and color-coded duplex sonography (CCDS) were used to identify carotid stenosis, which is associated with an increased risk of ischemic events due to CAS. METHODS: High resolution DW-MRI were performed in 74 out of 77 patients before and after CAS. All MRI scans were analyzed in a blinded manner. With CCDS each carotid stenosis was evaluated according to the grade, length, echo properties and plaque surface. RESULTS: In 42 out of 74 patients (56.8 %) a total of 188 new procedure- related DWI-lesions could be detected, while in 32 patients MRI-controls remained normal. Of the lesions 79.25 % had a size < 1 cm. In one major and two minor strokes due to CAS (total complication rate 3.9 %) corresponding territorial infarcts could be demonstrated. A highly significant correlation was found between the length of the stenosis and the incidence of new DWI-lesions (p = 0.0141). In contrast, neither the grade of ICA stenosis nor the sonographic plaque morphology or plaque surface correlated with the number of DWI-lesion in postinterventional scans. CONCLUSIONS: The length-and not the degree-of an ICA stenosis seems to be the most decisive sonographic factor for estimating the periprocedural risk of embolism. DWI-lesions are much more frequent than clinical complications and may represent an important surrogate marker for improving the techniques of carotid artery stenting, especially comparing the benefit of different mechanical protection devices.

Aged↗
PubMed2004

Transcervical carotid artery angioplasty and stenting with carotid flow reversal: surgical technique.

We have performed this technique in 40 patients with carotid artery stenosis. No deaths or strokes have occured. During the initial experience, one patient in whom flow reversal was not properly established sutained an hemispheric transient ischemic attack. Transcervical carotid artery balloon dilatation and stenting is feasible and safe. It establishes reliable cerebral protection before the carotid lesion is instrumented by reversing flow in the internal and external carotid arteries. It can be done under local anesthesia, and it avoids the potential limitations, complications, and additional cost of the transfemoral approach with protection devices.

Angioplasty↗
PubMed2005

Analysis of anatomic factors and age in patients undergoing carotid angioplasty and stenting.

Recent data suggest that patient age >80 years may be associated with increased risk of periprocedural complications from carotid angioplasty and stenting (CAS). In this study, we analyzed anatomic risk factors in patients undergoing CAS based on age >80 or <80 years. Our hypothesis was that patients >80 would have more challenging anatomy. Between February 2003 and August 2004, 82 patients underwent CAS. Images for 57 lesions were available for review. Eighteen patients were > or =80 years old and 39 were <80. Cerebral protection devices, including EPI Filterwire, Percusurge, Accunet, and Angioguard, were used in all but two cases; and self-expanding stents (Wallstent, NexStent, Acculink, Precise) were placed in all. Arterial anatomic characteristics were assigned a score based on complexity and associated procedural risk. Characteristics evaluated using angiographic images were aortic arch elongation classification, arch calcification, common carotid/innominate stenosis, common carotid tortuosity, internal carotid tortuosity, index lesion length, index lesion calcification, and index lesion stenosis. Statistical analysis was performed using Fisher's exact test. CAS was successfully completed in 98% of cases. The two patients in whom we could not perform CAS were 79 and 83 years old. The anatomic characteristics that were statistically significantly more complex/severe in patients > or =80 were arch calcification (p = 0.045), common carotid/innominate stenosis (p = 0.023), common carotid tortuosity (p = 0.049), and internal carotid tortuosity (p = 0.032). There was no statistically significant difference in arch elongation classification, lesion length, lesion calcification, or stenosis severity (p = nonsignificant). Overall, patients > or =80 years had an increased incidence of complex anatomic risk factors compared to younger patients (p < 0.001). Cerebrovascular accident without residual deficits occurred in two patients; both were >80 years old. Complex arterial anatomy is more often present in patients >80 years and may explain the increased complication rates associated with CAS. Pre- or intraoperative consideration of these characteristics may help provide better risk assessment in candidates for CAS.

Age Factors↗
PubMed2000

Treatment strategies for microvascular dysfunction following acute myocardial infarction.

Successful reperfusion following acute myocardial infarction is considered to be restoration of epicardial infarct vessel patency, but recent studies suggest that disrupted microvascular function and inadequate myocardial tissue perfusion are often present despite epicardial patency. New angiographic techniques, including the corrected Thrombolysis in Myocardial Infarction (TIMI) frame count and myocardial blush grade, have been used to demonstrate that restoration of downstream coronary flow and tissue perfusion may be the key links to improved clinical outcomes. Additionally, other diagnostic techniques, including infarct size measurement with cardiac marker release patterns, or (99m) Tc-sestamibi single photon emission computed tomography imaging, and analysis of ST-segment resolution have also been used to assess microvascular function and tissue perfusion. Promising adjunctive therapies that target microvascular dysfunction, including platelet glycoprotein IIb/IIIa inhibitors, anti-inflammatory agents, vasodilators, glucose-insulin-potassium, and embolization protection devices, may ameliorate microvascular dysfunction following epicardial reperfusion. However, these therapies have not yet been shown to improve clinical outcomes and are thus currently being studied together with fibrinolytics and primary angioplasty in clinical trials. Therefore, shifting the focus of reperfusion therapy to the microcirculation offers the potential to further improve myocardial salvage and clinical outcomes following acute myocardial infarction.

Coronary Angiography↗
PubMed2002

[Role of glycoprotein IIb/IIIa inhibitors in the treatment of degenerated aortocoronary saphenous vein grafts].

Treatment of degenerated vein grafts is a large, growing portion of interventional procedures. Because the operative risk of repeat bypass surgery is substantially increased, percutaneous transluminal coronary angioplasty has been accepted as a less invasive treatment in symptomatic patients with significant stenoses of vein grafts. Stent placement has been established in the randomized SAVED trial as a safe and efficient treatment strategy of degenerated saphenous vein grafts, enhancing acute success, reducing the incidence of subsequent angiographic restenosis, and improving event-free survival. Despite coronary stents and new technological innovations like directional and transluminal extraction atherectomy distal embolization is still a frequent occurrence, with a reported incidence of 10-15% associated with an increased in-hospital mortality. Blockade of the platelet surface glycoprotein IIb/IIIa receptors has been convincingly demonstrated to reduce the ischemic complications of angioplasty in native coronary arteries. In degenerated vein grafts the efficacy of glycoprotein IIb/IIIa inhibitors in reducing distal embolization is uncertain. Major clinical events could not be reduced by glycoprotein IIb/IIIa antagonists administered periprocedurally. But prospective randomized trials are lacking. Protection devices could reduce the incidence of distal embolization during interventions in degenerated saphenous vein grafts. The relative role of these devices compared to pharmacologic interventions will require careful assessment in future clinical trials.

Abciximab↗
PubMed1996

Safety-belt effectiveness: the influence of crash severity and selective recruitment.

While theoretical considerations show that the effectiveness of occupant protection devices declines from 100% at very low crash severity to 0% at high severity, empirical details have been lacking. When overall in-use effectiveness is estimated by applying traditional methods to data sets that lack a measure of severity, large biases are introduced because non-wearing drivers are riskier drivers, an effect that has been called selective recruitment. These effects are investigated empirically using National Accident Sampling System (NASS) data in which crash severity is measured by delta-v, the estimated change in the speed of the car as a result of the crash. Supplemental results are obtained using published police-reported data containing a more easily obtained but less objective severity measure. Both data sets provide information on driver fatalities and injuries, thus allowing four comparisons of effectiveness estimates based only on total casualties with ones taking into account the different severities of crashes by belted and unbelted drivers. The data show consistently that the probability that a driver is belted declines as crash severity increases. Belt effectiveness estimates ignoring this effect are biased upwards by large amounts (for example, 60% compared to 40% for injuries using NASS data). Belts appear more effective at preventing fatalities than at preventing injuries. The results are consistent with a prior estimate, derived using a method unaffected by the biases discussed here, which found that, averaged over all crashes, safety belts reduce driver fatality risk by (42 +/- 4).

Accidents, Traffic↗