Carotid intraplaque hemorrhage: the significance of neovascularity

Renewed interest in the neovascularity of atherosclerotic plaques has followed the work of Imparato et al., which confirmed the importance of carotid intraplaque hemorrhage in the production of symptomatic extracranial vascular disease. We have studied the detailed histology of 91 carotid atheromatous plaques with particular regard to hemorrhage and neovascularity and have confirmed the findings of earlier investigators while observing degenerative changes (not previously reported) in these new vessels. The possible role of systemic hypertension in intraplaque hemorrhage and the acceleration of the atherosclerotic process is discussed.     

Carotid intraplaque hemorrhage detected by magnetic resonance imaging predicts embolization during carotid endarterectomy

BACKGROUND: Microembolization detected during the dissection phase of carotid endarterectomy (CEA) is associated with plaque instability and might be associated with perioperative morbidity. Intraplaque hemorrhage is found in unstable plaques and is detectable using magnetic resonance imaging (MRI). We aimed to ascertain whether intraplaque hemorrhage as seen on carotid MRI predicts particulate embolization in the dissection phase of CEA. METHODS: Patients with high-grade symptomatic carotid stenosis undergoing CEA were prospectively enrolled. All underwent preoperative MRI assessment of the carotid arteries for intraplaque hemorrhage and transcranial Doppler scanning during the dissection phase of the CEA to assess the presence of microembolic signals. Associations between intraplaque hemorrhage and intraoperative microembolic signals were studied. RESULTS: Analysis was undertaken on 60 participants; of these, 36 (60%) showed ipsilateral carotid MRI intraplaque hemorrhage, and 24 (40%) did not. Microembolic signals were detected during the dissection phase in 23 (38.3%) participants, and 19 had MRI-detected intraplaque hemorrhage. The association between carotid intraplaque hemorrhage and the presence of dissection phase microembolic signals was significant (odds ratio [OR], 5.6; 95% confidence interval [CI], 1.6 to 19.7, P = .007), even after controlling for age, sex, individual surgeon, degree of stenosis, and delay from symptom to CEA (adjusted OR, 5.8; 95% CI, 1.1 to 30.4, P = .037). CONCLUSION: Intraplaque hemorrhage as detected by carotid MRI predicts particulate embolization during the dissection phase of CEA. This imaging technique can be used to identify patients with increased intraoperative thromboembolic risk, and this could influence preventive strategies.     

Carotid arterial hemorrhage after radical head and neck surgery.

From 1960 to 1974, 63 patients treated by the Head and Neck Service of Memorial Hospital underwent carotid arterial ligation for control of actual or threatened carotid rupture. Twenty-one of these patients died without leaving the hospital. Fourteen of these deaths were the direct result of carotid ligation or hemorrhage. Five of the surviving patients suffered permanent neurologic damage. Factors predisposing to carotid rupture included a history of radiation, advanced disease, the presence of an oral or pharyngeal suture line in continuity with a dissected neck, and the postoperative development of skin necrosis or fistulas. Because elective carotid ligation did not prevent the consequences of carotid rupture and because reestablishment of vascular continuity is almost never possible, all attempts should be made to avoid the conditions that are precursors to this most serious complication of radical head and neck surgery.     

无症状颈动脉粥样硬化斑块内出血与冠状动脉支架植入手术后脑梗塞和死亡的分析

目的 探讨无症状颈动脉狭窄（ACS）患者冠状动脉支架植入手术后并发脑梗塞和死亡的危险因素。方法 110例颈动脉面积狭窄达50%或以上的患者被纳入研究。回顾性分析术前颈动脉粥样硬化斑块内出血（IPH）等因素与术后同侧脑梗塞及死亡率的关系。结果 110例ACS患者中共发生16例IPH（14.5%）,其中有6例IPH（37.5%）和6例（6.4%）分别发生同侧脑梗塞和全因死亡。多变量Cox回归分析显示IPH是同侧脑梗塞和全因死亡率的预测因素（HR：18.47,95%CI：5.14~76.08,P<0.001）和全因死亡率（HR：4.26,95%CI：1.48~11.76,P=0.016）。结论 在接受冠状动脉支架植入手术的ACS患者中,IPH与术后脑梗塞和全因死亡率的高风险密切相关。     

Carotid plaque hemorrhage. Its role in production of cerebral ischemia

A prospective study of carotid endarterectomy specimens showed an acute or recent intraplaque hemorrhage in 49 of 53 plaques (92.5%) from symptomatic patients, compared with seven of 26 plaques (27%) from nonsymptomatic patients. Luminal stenosis of greater than 50% was noted in 46 of 53 symptomatic patients (75%), 43 of whose plaques had evidence of multiple hemorrhages. Intimal disruption (ulceration) occurred over protruding mounds of intraplaque hemorrhage and was associated with retinal cholesterol emboli and prolonged neurologic deficits. Mural recesses with the angiographic appearance of ulceration seldom showed intimal breakdown. Eighteen patients continued to have symptoms while receiving aspirin, 13 of whom had had multiple intraplaque hemorrhages. Angioneogenesis occurred within the plaques in response to hemorrhage, creating vascular lesions vulnerable to mechanical stress and capable of producing further hemorrhage or intimal disruption.     

Experimental simulation study on hemodynamics in multiple cerebral arterial stenoses and EC-IC bypass

In recent years, unilateral or bilateral multiple stenoses in the internal carotid artery have been increasing in number. Full understanding and complete analysis of these hemodynamics are, however, sometimes difficult because multiple factors such as number, size and location of the stenotic lesions, and capacity of collateral circulation differ with individual cases and are related mutually in complex fashions. One of the effective means to solve these problems is to study the hemodynamics and to simulate their changes after an expected operative procedure by the use of a hydraulic vascular model, where any factor can be managed independently. A vascular model of the internal carotid artery (ICA) has been manufactured with silicone and glass tubes in similar dimensions to averaged adults. Peripheral vascular resistance (Rp) is so adjusted as to obtain an arterial flow of 180 ml/min at an intraluminal pressure of 60 mmHg. Four kinds of stenosis segments, Ra (2.59 mm in diameter), Rb (1.94 mm), Rc (1.12 mm) and Rd (0.84 mm) are prepared and used in various models simulating unilateral multiple stenoses, unilateral solitary long stenosis and bilateral multiple stenosis. The results obtained are; 1. In case of two stenoses of different degree arranged in series, advanced one was found to have a dominant effect on flow reduction. This implies that only its removal can results in good augmentation of flow in unilateral multiple stenoses of the ICA. 2. In case of more than three stenoses of the some degree arranged in series, increase in flow can not be obtained until the last one is cleared.(ABSTRACT TRUNCATED AT 250 WORDS)     

Effects of head posture on cerebral hemodynamics: its influences on intracranial pressure, cerebral perfusion pressure, and cerebral oxygenation

OBJECTIVE: Severely head-injured patients have traditionally been maintained in the head-up position to ameliorate the effects of increased intracranial pressure (ICP). However, it has been reported that the supine position may improve cerebral perfusion pressure (CPP) and outcome. We sought to determine the impact of supine and 30 degrees semirecumbent postures on cerebrovascular dynamics and global as well as regional cerebral oxygenation within 24 hours of trauma. METHODS: Patients with a closed head injury and a Glasgow Coma Scale score of 8 or less were included in the study. On admission to the neurocritical care unit, a standardized protocol aimed at minimizing secondary insults was instituted, and the influences of head posture were evaluated after all acute necessary interventions had been performed. ICP, CPP, mean arterial pressure, global cerebral oxygenation, and regional cerebral oxygenation were noted at 0 and 30 degrees of head elevation. RESULTS: We studied 38 patients with severe closed head injury. The median Glasgow Coma Scale score was 7.0, and the mean age was 34.05 +/- 16.02 years. ICP was significantly lower at 30 degrees than at 0 degrees of head elevation (P = 0.0005). Mean arterial pressure remained relatively unchanged. CPP was slightly but not significantly higher at 30 degrees than at 0 degrees (P = 0.412). However, global venous cerebral oxygenation and regional cerebral oxygenation were not affected significantly by head elevation. All global venous cerebral oxygenation values were above the critical threshold for ischemia at 0 and 30 degrees. CONCLUSION: Routine nursing of patients with severe head injury at 30 degrees of head elevation within 24 hours after trauma leads to a consistent reduction of ICP (statistically significant) and an improvement in CPP (although not statistically significant) without concomitant deleterious changes in cerebral oxygenation.     

Carotid and vertebral arterial injuries

Injuries of the extracranial cerebral vessels represent only a small fraction of all reported arterial injuries but pose a significant dilemma over whether to repair or ligate the involved vessel. This article reviews recognition and repair of both penetrating and blunt injuries of the carotid and vertebral arteries, with special comment on the surgical exposure of the less accessible injuries.     

Clinical relevance of intraplaque hemorrhage in the internal carotid artery.

In this study the correlation between hemispherical ischemic symptoms and the presence of intraplaque hemorrhage in carotid plaques has been evaluated. 38 patients who had undergone carotid endarterectomy were examined clinically and the specimens obtained from operation were studied morphologically. The patients were divided into two groups, asymptomatic and symptomatic regarding the territory of the supplying carotid artery. The presence of intraplaque hemorrhage, shown by Ladewig's Trichrom stain, as well as evidence of iron, immunohistochemical stain of hemoglobin and native fluorescence microscopy was noted, and, according to their extension, classified into three degrees. As a result, there was neither a correlation between history of ischemic brain symptoms and the presence of intraplaque hemorrhage, nor between clinical symptoms and extension of hemorrhage. The plaques were high degree stenotic (greater than 80%) in most of the patients and showed various degenerative changes. In 97% of all plaques with hemorrhages surface defects were seen. Our results confirm that intraplaque hemorrhage is one out of a series of pathological events which occurs during advanced atherosclerosis. Blood inflow from the lumen through an already damaged plaque surface is a common event and a correlation with the onset of symptoms is unlikely.     

气流冲击法清除气囊上滞留物对重症脑出血患者脑血流动力学的影响

目的 探讨气流冲击法清除气囊上滞留物对重症脑出血患者颅内压及脑灌注压的影响,了解此操作用于颅内压增高风险患者的可行性.方法 采用前瞻性研究方法,选取重症脑出血机械通气患者40例,采用气流冲击法清除人工气道气囊上滞留物,记录并比较操作前中后各观察指标变化.结果 气流冲击法操作不同时间患者颅内压、心率、平均动脉压比较,差异有统计学意义(均P＜0.01);操作中患者颅内压、心率、平均动脉压显著高于操作前后,脉搏氧饱和度显著低于操作前后(均P＜0.01);操作前中后脑灌注压差异无统计学意义(P＞0.05).气流冲击法操作后患者呼吸频率显著低于操作前(P＜0.05),潮气量及分钟通气量操作前后差异无统计学意义(均P＞o.05).结论 对重症脑出血患者采用气流冲击法清除气囊上滞留物,可引起重症脑出血患者短暂颅内压波动及脉搏氧饱和度、心率、平均动脉压变化,但均在正常范围波动,对患者脑氧合及脑灌注量影响较小.     

Association of acromegaly and a cerebral arterial aneurysm disclosed by a subarachnoid hemorrhage

The association of acromegaly and cerebral aneurysm is an infrequent clinical finding, being few the cases reported in literature. A major incidence of cerebral aneurysm in patients with other pituitary adenoma and cerebral tumour has been described, in relation to the general population. We have studied a male patient, aged 37 years old, with an acromegaly disease initiated 5 years before, that came to our hospital because of subarachnoid hemorrhage symptomatology. A right middle cerebral aneurysm was found in surgery. Hormonal studies confirmed a high basal Growth Hormone (64 ng/ml) that was not suppressed during an Oral Glucose Tolerance Test (75 g). A triple stimulus test (Insulin, TRH, LHRH) demonstrated non-response of GH to TRH and hypoglycemia others hormones were normal. Radiological studies were suggestive of Acromegaly disease. Computed axial tomography showed an intra-sellar tumour. The patient was operated (Transsphenoidal surgery) and a GH pituitary secreting tumour found, without suprasellar extension. The clinical significance and importance of the coexistence of the Acromegaly and Cerebral Aneurysm is discussed, with a review of hypothesis implicated.     

颈动脉内膜切除术与脑保护

目前颈动脉硬化闭塞性疾病已公认为是引起脑中风的主要原因，而早期、及时的诊治是降低脑中风发病率的关键。     

Idiopathic arterial calcification of infancy

Summary We describe two twin sisters in whom calcification of different arteries was detected in the first weeks of life. Transient renal insufficiency, arterial hypertension, and skeletal abnormalities were also observed. One child had anasarca and heart decompensation at birth. Prenatal infarction of one kidney had occurred in the same infant. A kidney biopsy showed calcium deposits in all the layers of the arteries. Most findings in these patients are compatible with idiopathic arterial calcification of infancy (IACI). Investigation of calcium and phosphorus metabolism revealed spontaneously receding hypercalciuria, increased intraerythrocytic calcium levels, and transient X-ray abnormalities of the long bones. Treatment initially consisted of biphosphonate and later, the calcium antagonist flunarizin. A progressive diminution of the arterial calcification was observed in the course of both treatments.     

Carotid doppler hemodynamics in posttraumatic intracranial hypertension

Repeated Doppler sonograms were performed on the common carotid arteries of patients with severe brain injury. The evolution of the flow-wave shape in 9 patients who developed massive intracranial hypertension and finally died with cerebral circulatory arrest demonstrated that, with increasing peripheral vascular resistance, the diastolic flow diminished while the peak systolic flow was not significantly affected. Thus, the so-called pulsatility index, a measure of the pulsatile characteristic of the sonogram, can be used as a semiquantitative measure of intracranial perfusion. Measurements on healthy control subjects provided pulsatility indexes between 1.5 and 2.0. In cases of posttraumatic brain edema, these values increased gradually. These data suggest that values higher than 3 are associated with severe intracranial hypertension and the decerebrate state. In angiographically demonstrated cerebral circulatory arrest, the pulsatility index was found to range between 6 and 8.     

Deficiencies of physiologic calcification inhibitors and low-grade inflammation in arterial calcification: lessons for cartilage calcification

Apart from clinical parallels, similarities in the pathogenesis of arterial and articular cartilage calcification have come to light in recent years. These include the roles of aging, of chronic low-grade inflammation and of genetic and acquired dysregulation of inorganic pyrophosphate (PP(i)) metabolism. This review focuses on recent developments in understanding the pathogenesis of artery calcification pertinent to interpretation of the mechanistic basis for articular cartilage calcification in aging and osteoarthritis.