Acute Thromboembolic Occlusion Research Articles

Endovascular and open surgery for acute occlusion of the superior mesenteric artery

Acute thromboembolic occlusion of the superior mesenteric artery (SMA) is associated with high mortality. Recent advances in diagnostics and surgical techniques may affect outcome. Through the Swedish Vascular Registry (Swedvasc), 121 open and 42 endovascular revascularizations of the SMA at 28 hospitals during 1999 to 2006 were identified. Patient medical records were retrieved, and survival was analyzed with multivariate Cox-regression analysis. The number of revascularizations of the SMA increased over time with 41 operations in 2006, compared to 10 in 1999. Endovascular approach increased sixfold by 2006 as compared to 1999. The endovascular group had thrombotic occlusion (P < .001) and history of abdominal angina (P = .042) more often, the open group had atrial fibrillation more frequently (P = .031). All the patients in the endovascular group, but only 34% after open surgery, underwent completion control of the vascular reconstruction (P < .001). Bowel resection (P < .001) and short bowel syndrome (SBS; P = .009) occurred more frequently in the open group. SBS (hazard ratio [HR], 2.6; 95% confidence interval [CI], 1.3-5.0) and age (HR, 1.03/year; 95% CI, 1.00-1.06) were independently associated with increased long-term mortality. Thirty-day and 1-year mortality rates were 42% vs 28% (P = .03) and 58% vs 39% (P = .02), for open and endovascular surgery, respectively. Long-term survival after endovascular treatment was better than after open surgery (log-rank, P = .02). The results after endovascular and open surgical revascularization of acute SMA occlusion were favorable, in particular among the endovascularly treated patients. Group differences need to be confirmed in a randomized trial.

Use of the Enterprise™ Intracranial Stent for Revascularization of Large Vessel Occlusions in Acute Stroke

Major cerebral thromboembolism often resists recanalization with currently available techniques. The authors present their initial experience with a self-expanding stent for use in intracranial vascular reconstruction, permitting immediate recanalization of acute thromboembolic occlusions of the anterior circulation. Patients treated with the Cordis Enterprise™ self-expanding intracranial stent system for acute thromboembolic occlusion of the major anterior cerebral arteries were included. Treatment comprised systemic and intraarterial thrombolysis, mechanical thrombectomy, and stent placement. Stent deployment, recanalization rate by means of Thrombolysis In Cerebral Infarction (TICI) scores and the clinical outcome were all assessed. Six patients presenting with acute carotid T (n = 2) or proximal middle cerebral artery occlusion (n = 4) were treated. The mean National Institutes of Health Stroke Scale (NIHSS) score at presentation was 14; the mean age was 57 years. Successful stent deployment and immediate recanalization were achieved in all six with a TICI score of ≥ 2. Neither distal emboli nor any procedure-related complications were encountered. One patient developed symptomatic intracerebral hemorrhage and two patients needed decompressive craniectomy after treatment. The mean NIHSS score at 10 days was 10, but only one patient showed a complete recovery at 3 months. Intracranial placement of the Enterprise™ self-expanding stent has proven to be feasible and efficient in achieving immediate recanalization of occluded main cerebral arteries. The use of antiplatelet therapy after treatment may, however, increase the risk of reperfusion intracerebral hemorrhage.

Radiologisch-interventionelle Maßnahmen beim akuten Abdomen

In patients with acute thrombo-embolic occlusion of the superior mesenteric artery, catheter-assisted thrombolytic therapy represents a procedure of increasing importance in addition to surgery and intensive care treatment. The thrombolytic drugs utilized for this purpose are urokinase, streptokinase and recombinant tissue plasminogen activator (rtPA).Therapeutic embolization is predominantly used in the treatment of arterial bleeding from the gastro-intestinal tract, the liver, the intestines (due to an aneurysm or vascular malformation) and in bleeding from intestinal anastomoses. Polyvinyl alcohol particles, embospheres, gelfoam and microcoils can be utilized as embolic agents. Percutaneous transhepatic cholangiodrainage and stent implantation are applied in patients with biliary obstructions caused by inoperable tumors of the gall bladder or bile ducts, of the pancreatic head or duodenum and by metastases located in the liver parenchyma or hepatic hilum.Image-guided percutaneous drainage is a valuable option in the management of abscesses in the peritoneal cavity; less common indications are lymphoceles, biliomas, urinomas, hematomas, necrosis and pseudocysts.

Brain salvage for cardiac cerebral embolism following myocardial infarction

Acute ischemic stroke due to thromboembolism from the left ventricle is a serious complication following myocardial infarction (MI). Despite the attention given to acute stroke intervention, peri-MI ischemic stroke is an underappreciated condition. Here, we describe a case of acute cardiac thromboembolic occlusion of the middle cerebral artery with preceding MI in which brain salvage was achieved by balloon angioplasty.

Penumbra System: A Novel Mechanical Thrombectomy Device for Large-Vessel Occlusions in Acute Stroke

Large IC artery occlusion is often resistant to recanalization. We present our initial experience with the PS. Presenting with a severe acute ischemic stroke, the first 27 consecutive patients were considered for thromboaspiration therapy and retrospective data base analysis. All patients received standard thrombectomy treatment as monotherapy or in combination with thrombolysis or IC stent placement. The primary end point was revascularization of the target vessel to grade 2 or 3 on the TICI scale. Secondary end points were improvement of >4 points on the NIHSS score at discharge and favorable outcome, and improvement in overall mortality at 3 months and in sICH- and procedure-related adverse events. At baseline, the mean age was 66 +/- 14 years and the mean NIHSS score was 14 +/- 7. The anterior circulation was affected in 23 patients, and there were 4 basilar artery occlusions. Intracranial stent placement was performed in 4 patients. A recanalization to TICI 2 or 3 was achieved in 25 patients (93%). None of the patients developed sICH. At hospital discharge, 15 patients (56%) had an NIHSS improvement of >4 and 13 patients (48%) had an mRS score of <2 at 3 months. There was a significant correlation between complete vessel recanalization and favorable outcome. The all-cause mortality at 3 months was 11%. The PS showed a high potential for recanalization of acute thromboembolic occlusions of the large cerebral arteries. Complete recanalization was strongly correlated with good clinical outcome.

Sudden death from acute thromboembolic occlusion of the left coronary ostium

The patient was a 55-year-old woman who experienced anterior chest pain after drinking a cup of coffee. The patient had no risk factor for cardiac disease other than mild non- insulin-dependent diabetes mellitus. The patient did have a history of asthma and was on a steroid taper, taking 20 mg of prednisone daily. The patient's physical examination results were within normal limits. Her laboratory data were normal, except for a glucose level of 499 mg/dl and a urinalysis revealing more than 4+ glucose with large ketones. Venous blood gas pH was 7.36, and troponin I, creatinine kinase-MB, electrocardiogram, and chest film were normal. The patient was admitted to rule out acute coronary syndrome. During the placement into an inpatient bed, the patient sustained a cardiac arrest with a narrow complex ventricular rhythm without pulse, from which she could not be resuscitated. The postmortem examination of the lungs revealed no evidence of thromboemboli. The coronary arteries revealed mild atherosclerosis. Examination of the aortic root revealed complete occlusion of the left coronary ostium by a large premortem nonorganized fresh thromboembolus, which was easily removed by passing a probe retrograde from the left main coronary artery (Fig. 1). Microscopically, there were also small thromboemboli in both the distal right and left coronary intramyocardial vessels. An extensive search of the heart and all major vessels was undertaken to identify the source of the possible thromboemboli, and none could be identified. A Medline search of the literature revealed no other similar case.

Impact of MDCT with intravenous contrast on the survival in patients with acute superior mesenteric artery occlusion

Acute thromboembolic occlusion in the superior mesenteric artery (SMA) is a condition with high mortality and morbidity. Multi-detector computerised tomography with intravenous contrast enhancement (MDCTiv) may improve diagnostic accuracy and survival. Patients with acute SMA occlusion were identified between 2004 and 2008 at Malmö University Hospital, Sweden. Medical records were analysed. Each MDCTiv was re-evaluated. A total of 67 patients were identified with SMA occlusion, of which 36 were examined with MDCTiv and ten with plain MDCT without intravenous contrast. In all, 24 (67%) of the 36 patients were correctly diagnosed by MDCTiv at first evaluation. Clinical suspicion of intestinal ischemia followed by a distinct inquiry for intestinal ischemia was associated with trend for a higher rate of correct radiological diagnosis, 18 of 23 (78%), at first evaluation (0.06) but without affecting in-hospital survival (p = 0.27). At re-evaluation, SMA occlusion was found in all cases with MDCTiv, whereas intestinal findings were present in half. In-hospital mortality rate was 42% for patients who underwent MDCTiv, which was significantly lower compared to 90% for the ten patients examined with plain MDCT (p = 0.007) and 71% for patients not examined with MDCTiv or plain MDCT (p = 0.031). Patients that underwent plain MDCT had higher levels of creatinine compared to those examined with MDCTiv (p = 0.005). Patients who underwent intestinal revascularisation, endovascular or open, had higher survival rate (p = 0.001). Examination with MDCTiv in patients with acute SMA occlusion was associated with survival benefit. Hence, MDCTiv seems to be the method of choice in the workup phase. Radiologists should routinely describe the mesenteric vessels in patients with acute abdomen even when the diagnosis is not asked for. Patients with high creatinine levels are at risk to be examined without intravenous contrast, and survival in these patients is poor.

Intra-Arterial Thrombolytic Therapy for Acute Basilar Occlusion

Acute thromboembolic occlusion of the basilar artery accounts for 6% to 10% of large-vessel stroke in humans. Because of the brain region supplied by this artery, the case fatality rate is the highest for all ischemic stroke subtypes, ranging from 40% to 86%. Patients who undergo successful recanalization of the basilar artery by intra-arterial thrombolysis have lower mortality of approximately 39%. Considering all published series, a consistent survival benefit is predicted by revascularization (mortality 87% nonrecanalized compared with 39% recanalized; P<0.001). Although no large randomized studies of revascularization for acute basilar artery occlusion have been performed, it is unlikely that endovascular efforts are inferior to the natural history of the disease, and it is likely that patients benefit from this aggressive approach.

Progression of Middle Cerebral Artery Susceptibility Sign on T2*-Weighted Images: Its Effect on Recanalization and Clinical Outcome After Thrombolysis

The middle cerebral artery (MCA) "susceptibility sign" on T2*-weighted imaging has been reported to indicate acute thrombotic occlusion. We evaluated the serial progression of this susceptibility sign on follow-up MRI and its effect on recanalization and clinical outcome after intraarterial thrombolysis. Thirty-three acute ischemic stroke patients who were treated with intraarterial thrombolysis and underwent MRI within 6 hours of symptom onset were enrolled in this study. All study participants had either M1 or M2 occlusion on digital subtraction angiography before thrombolysis and underwent follow-up MRI 2-3 days after thrombolysis. Recanalization status was evaluated using the thrombolysis in myocardial infarction (TIMI) flow grade on digital subtraction angiography immediately after thrombolysis. The serial progression of the susceptibility sign on follow-up T2*-weighted imaging was compared with the MR angiographic findings. Baseline clinical parameters and clinical outcome were also reviewed. A positive MCA susceptibility sign on the initial T2*-weighted imaging was detected in 16 (48%) of the 33 patients. The mean TIMI grade was higher in the patients with a positive sign on imaging than in those without the sign (2.3 vs 1.0, respectively; p < 0.005). In the risk factor analysis, a history of atrial fibrillation was significantly higher in the patients with the MCA susceptibility sign than in those with negative findings for the sign (13/16 [81%] vs 4/17 [24%], respectively). In 14 of the 16 patients with the positive sign, the sign disappeared on follow-up MRI, and that finding (i.e., disappearance of the sign) was well correlated with complete recanalization on follow-up MR angiography in 12 patients. Multivariate logistic regression analysis showed that this sign was not associated with a favorable functional outcome 30 days after thrombolytic treatment. The MCA susceptibility sign can be indicative of acute thromboembolic occlusion and can be used to predict the immediate effectiveness of intraarterial thrombolysis. However, the appearance of this sign was not associated with a favorable clinical outcome after thrombolysis in our small series study.

Direct aspiration using rapid‐exchange and low‐profile device for acute thrombo‐embolic occlusion of the superior mesenteric artery

Acute thrombo-embolic occlusion of the superior mesenteric artery (SMA) is potentially fatal vascular emergency that requires rapid restoration of mesenteric blood flow as well as early diagnosis. Selective thrombolysis has been employed for this life-threatening event. Although failed thrombolysis is a well known phenomenon, which is directly connected with bowel necrosis, emergent laparotomy, and patient death, little progress has been made in its treatment strategy. Recently, direct aspiration using rapid-exchange and low-profile aspiration device has been reported as a simple, safe, and effective strategy to thrombus in coronary artery. We describe the utility of direct aspiration using this sort of aspiration device for failed thrombolysis of SMA thrombo-embolism.

Acute lower limb ischemia due to thrombo-embolic arterial occlusions in two previously healthy men with markedly elevated Lp(a)

Lipoprotein (a) (Lp(a)) is a well-documented risk factor for atherosclerotic cardiovascular disease. Its role in acute thrombo-embolic occlusions of peripheral arteries is not known. We describe two cases of multiple, acute, peripheral arterial occlusions in two previously healthy men with markedly elevated Lp(a). Both cases had unsatisfactory results after percutaneous and surgical revascularization procedures. Experience yielded in these two cases suggests that when an unfavorable outcome occurs in a peripheral artery disease patient in the absence of the regular risk factors, Lp(a) should be determined and its role investigated.

Percutaneous endovascular treatment of acute sequential systemic emboli

A 65-year-old woman was evaluated for acute right lower-extremity ischemia secondary to embolization from atrial fibrillation and subtherapeutic anticoagulation. Her symptoms quickly evolved in a dynamic fashion to involve multiple vascular beds, including a transient ischemic attack, abdominal pain secondary to mesenteric ischemia, and contralateral lower-extremity ischemia. Synchronous emboli were treated by using mechanical and pharmacologic thrombolysis via an endovascular approach under local anesthesia. This intervention allows prompt evaluation of multiple vascular beds with good short-term outcomes and minimal morbidity.

Clinical Implications for the Management of Acute Thromboembolic Occlusion of the Superior Mesenteric Artery

To study findings at autopsy in patients with fatal acute thromboembolic occlusion of the superior mesenteric artery (SMA). Acute occlusion of the SMA is difficult to diagnose and mortality remains high. In Malmo, Sweden, the autopsy rate between 1970 and 1982 was 87%, creating possibilities for a population-based study. Among 23,496 clinical autopsies and 7569 forensic autopsies, 213 cases with acute thromboembolic occlusion of the SMA and intestinal infarction were identified. A clinical suspicion of intestinal infarction was documented in 32% of the patients, only 35% being in the care of surgeons. The embolus/thrombus ratio was 1.4 to 1. Thrombotic occlusions were located more proximally than embolic occlusions (P < 0.001), intestinal infarction was more extensive (P = 0.025) and thrombotic occlusions were associated with old brain infarction (P = 0.048), aortic wall thrombosis (P = 0.080), and disseminated cancer (P = 0.079). Patients with embolic occlusions (n = 122) had a higher frequency of acute myocardial infarction (AMI) than patients with thrombotic occlusions (P = 0.049). The embolic source was identified in 80%. In 115 (94%), synchronous embolism and/or source of embolus were present. There were findings of remaining cardiac thrombi in 58 (48%) and synchronous emboli affected 273 other arterial segments in 83 (68%). Early recognition and revascularization would have been a prerequisite for survival in at least half of the patients, since the jejunum, ileum, and colon were affected by infarction. A minority of all patients were under surgical care. AMI, cardiac thrombi, and synchronous emboli were common findings among patients with embolic occlusions.

Fibrinolysis of Acute Peripheral Arterial Occlusion with Tenecteplase?A New Weight-Optimized Treatment Regimen

Peripheral arterial occlusions are associated with high morbidity. Thrombolysis has become established as effective treatment in clinical practice. Tenecteplase is a new thrombolytic agent that offers advantages over existing drugs with respect to mechanism of action and adverse effects. This case report describes successful thrombolysis of an acute thromboembolic brachial artery subtotal occlusion in a 76-year-old woman. In contrast to previously published data, tenecteplase was administered in a weight-adapted dose regimen over six hours, with application of one-fourth of the dose usually given in patients with myocardial infarction. Tenecteplase was immediately effective, and proved safe and well tolerated.

Strategy for the Treatment of Acute Thromboembolic Stroke Involving an Internal Carotid Artery

With the recent improvement of endovascular techniques, intra-arterial local fibrinolytic therapy has become widely available for treatment of acute embolic stroke and there is some evidence that it could be superior to conventional approaches (1-6). However, because of high mortality and morbidity, strokes involving the internal carotid artery (ICA) and featuring acute thromboembolic occlusion remain problematic (7). We have successfully performed intra-arterial local fibrinolytic therapy via the anterior communicating artery through the contra-lateral ICA in two consecutive cases of thromboembolic occlusion of the ICA, anterior cerebral artery (ACA) and middle cerebral artery (MCA), and obtained satisfactory results.We here present details of this new technique applied for the two cases and discuss the efficacy of this method compared with conventional approaches.

Incidence of Acute Thrombo-Embolic Occlusion of the Superior Mesenteric Artery—A Population-based Study

Objective. To determine the incidence of acute thrombo-embolic occlusion of the superior mesenteric artery (AOSMA) in a population-based study.Material. All clinical (n=23,446) and forensic (n=7569) autopsies performed in the city of Malmö between 1970 and 1982 (population 264,000–230,000 inhabitants). The autopsy rate was 87%.Methods. Calculation of the incidence of AOSMA with intestinal gangrene in those autopsies coded for bowel ischaemia (997/23,446 clinical and 9/7569 forensic autopsies). The operative procedures performed in 1970, 1976 and 1982 were also analysed.Results. Two forensic and 211 clinical autopsies demonstrated AOSMA with intestinal gangrene. Previous suspicion of intestinal ischaemia was noted in only 33%. Sixteen patients were operated. The cause-specific mortality was 6.0/1000 deaths. The incidence was 8.6/100,000 person years, increasing exponentially with age (p<0.001). Mortality was 93%.Conclusions. The incidence and mortality of AOSMA is higher than previously reported from clinical series. There is seldom any suspicion of the diagnosis prior to death.

Acute thrombo-embolic occlusion of the superior mesenteric artery: A prospective study in a well defined population

Objectives: to characterize the clinical presentation of patients with acute thrombo-embolic occlusion of the superior mesenteric artery (SMA). Design: prospective study. Materials: twenty-four consecutive patients admitted to Blekinge County Hospital, Karlskrona, Sweden, with acute thrombo-embolic occlusion of the SMA, over a three-year period from April 1999 through March 2002. Methods: clinical data were registered prospectively. Incidence, diagnostic procedures and factors associated with survival were analysed. Results: the diagnosis was verified at operation in 20, and at autopsy in 4 patients. The incidence was 5.3 per 100 000 inhabitants per year. Among the 20 patients with embolic disease, atrial fibrillation was present in 95%, synchronous embolic events in 30% and warfarin treatment in 10%. D-dimer was elevated on admission in 13/13. Four patients were diagnosed at first consultation. Fifteen underwent curative revascularisation (6) or bowel resection only (9). Five were alive at one-year follow-up, of whom one had short bowel syndrome. Length of bowel ischaemia predicted institutional (p = 0.004) and one-year mortality (p = 0.005). Conclusions: the incidence was higher than expected. Embolic occlusions predominated. Old age, atrial fibrillation, severe abdominal pain and synchronous embolus suggest the diagnosis of acute bowel ischaemia. Length of bowel ischaemia predicted outcome.Eur J Vasc Endovasc Surg 26, 179-183 (2003)

Revascularization of the superior mesenteric artery after acute thromboembolic occlusion.

The outcome and prognostic factors after revascularization of acute thromboembolic occlusion of the superior mesenteric artery (SMA) are poorly documented. Sixty patients with acute thromboembolic occlusion of the SMA had revascularization procedures at 21 hospitals from 1987 to 1998. They were registered prospectively in the Swedish Vascular Registry. Patient files were analysed retrospectively. The median age of the patients was 76 years; 73 per cent suffered from cardiac disease and 23 per cent had previous vascular surgery. Onset of symptoms was classified as sudden (30 per cent), acute (33 per cent) or insidious (37 per cent). The occlusions were thought to be either embolic (67 per cent) or thrombotic (33 per cent). The diagnosis was suspected on first examination in 32 per cent of patients, a group whose median time to operation was shorter (P = 0.01). Fifty-eight patients had an exploratory laparotomy and subsequent revascularization, and two were treated with thrombolysis alone. Second-look laparotomy was performed in 41, and third look in eight patients; 19 required an additional bowel resection. The overall mortality rates were 43, 52, 60 and 67 per cent at 30 days, discharge, 1 and 5 years, respectively. No patient was dependent on intravenous nutrition after 1 year. Previous vascular surgery resulted in a higher institutional mortality rate (79 per cent; P = 0.02). Patients who had a sudden onset of symptoms outside hospital had a better outcome (mortality rate 27 per cent; P = 0.02). Many non-diagnostic radiological examinations were performed and a routine second-look is warranted. The results suggest that attempts at revascularization procedures for acute mesenteric ischaemia may improve the outcome.

Rt-PA thrombolysis in acute thromboembolic upper-extremity arterial occlusion.

Retrospective analysis of the results of rt-PA thrombolysis in the treatment of acute thromboembolic occlusion of the upper limb. Of 55 patients with demonstrated acute embolic arterial occlusion, rt-PA thrombolysis was performed on 40 occlusions in 38 patients (23 women with a mean age of 62 years, range 32-85 years; 15 men with a mean age of 65 years, range 32-92 years) according to the following design: 6 mg rt-PA/hr for 30 min, 3 mg rt-PA/hr for the next 30 min, 1 mg rt-PA/hr for 7 hr, and 0.4 mg rt-PA/hr until the end of lysis. Onset of symptoms varied from 1 to 14 days. Included were three isolated upper-arm occlusions, nine combined brachial and forearm occlusions, and 28 forearm and hand artery occlusions. The overall success rate was 55%. The lysis results for isolated upper arm, combined brachial and forearm occlusions, and forearm and hand artery occlusions were 100%, 66%, and 46%, respectively. In eight patients surgical embolectomy had to be performed after failed thrombolysis. No amputation was required in the follow-up period. No lethal complications occurred. Interventional rt-PA treatment of proximal upper-extremity arterial occlusions may be performed with comparable success rates to surgical embolectomy and without severe complications. For distal occlusions the results are inferior to the success rates obtained with surgery.

Understanding and managing ischemic stroke

Transient or permanent focal brain injury following acute thromboembolic occlusion develops from a complex cascade of pathophysiological events. The processes of excitotoxicity, peri-infarct depolarisation, inflammation, and apoptosis within the ischemic penumbra are proposed. While the translation of therapeutic agents from the animal models to human clinical trials have been disappointing, there remains an atmosphere of optimism as a result of the development of new diagnostic and therapeutic approaches, which include physiological, as opposed to pharmacological, intervention. This article provides an insight into the understanding of cerebral ischemia, together with current and future treatment strategies.