Mitral Annular Calcification Detected by Transthoracic Echocardiography is a Marker for High Prevalence and Severity of Angiographically Proven Coronary Artery Disease

Background: MAC was defined as a dense, localized, highly reflective area at the base of the posterior mitral leaflet detected by TTE. Obstructive CAD was defined as either 50% reduction of the internal diameter of the left main coronary artery or 70% reduction of the internal diameter of the left anterior descending, right coronary, or left circumflex artery distribution. Objective: The aim of the study was to evaluate the role of echocardiographically detected MAC as a predictor of coronary artery disease (CAD).Material & Methods:In this prospective, observational, case-control study, coronary angiography was done in 50 patients with MAC and equal number of patients without MAC, detected with transthoracic echocardiography. Analysis was done to observe the association and correlation of MAC with angiographic findings.Results:Mean age of the case control was 55.16 � 10.73 years and control was 49.80 � 8.84 years. In this study 34% of patients with MAC and 32% patients without MAC had single vessel disease, 16% of patients with MAC and 24% patients without MAC had double vessel disease, 42% of patients with MAC and 22% patients without MAC had triple vessel disease (TVD), 16% of patients with MAC and 4% patients without MAC had Left main coronary artery disease and 8% of patients with MAC and 22% patients without MAC had no significant CAD.Multivariate analysis shows MAC (p=0.049) as an independent predictor for coronary artery disease (CAD).Conclusions:Transthoracic echocardiographically detected MAC is an independent predictor of coronary artery disease. The low cost, portable and radiation free nature of the ultrasound approach make MAC an attractive parameter in the ongoing search for the ideal marker of coronary artery disease (CAD).

Surgical Treatment of Intracranial Angiographically Occult Vascular Malformations Hemorrhage:40 Cases Report / 中国康复理论与实践

@#ObjectiveTo review the surgical technique and outcome of intracranial angiographically occult vascular malformations (AOVM) hemorrhage. Methods40 patients with spontaneous intracranial hemorrhage episodes and accepted microsurgery were analyzed retrospectively. ResultsAll AOVMs were successfully resected. No operative death occurred.36 patients were followed up for mean 28 months. CT and/or MRI revealed no residual lesions. Most neurological complications improved postoperatively. 1 case demonstrated rebleeding in surgical site 48 months after operation. Another case, a follow-up MRI scan revealed a contralateral denovo lesion 44 months after operation.ConclusionA current neurosurgical procedure is a satisfactory method to prevents AOVMs rebleeding. Long-term follow-up evaluation is necessary despite the lesion has been totally resected.

Assessment of Coronary Flow Velocity Reserve by Noninvasive Transthoracic Doppler Echocardiography in Patients with Angiographically Normal Coronary Arteries / 华中科技大学学报（医学）（英德文版）

The measurement of coronary flow velocity reserve (CFVR) by transthoracic Doppler echocardiography (TTDE) with invasive intracoronary Doppler flow wire technique (ICD) was validated and the pathologicalfactors which influence CFVR in patients with angiographically normal coronary arteries were analyzed. CFVR was determined successfully in left anterior descending artery (LAD) in 37 of 40 patients with angiographically normal coronary arteries (men 22, women 15, age 20-75 years, mean age 54 ± 12 years). Coronary flow velocity was measured in the distal LAD by TTDE with contrast enhancement at baseline and during intravenous adenosine infusion of 140 μg/kg per min within 48 h after ICD technique. Average peak velocity at baseline (APVb), average peak velocity during hyperemia (APVh) and CFVR determined from TTDE were correlated closely with those from ICD measurements (APVb: y=0. 64x+5. 04, r=0. 86, P＜0. 001;APVh: y=0.63x+14.36, r=0.82, P＜0.001; CFVR: y=0.65x+0.92, r=0.88, P＜0. 001).For CFVR measurements, the mean differences between TTDE and ICD methods were 0. 12 ±0.39. CFVR in patients with history of hypertension was significantly lower than that in patients without history of hypertension (P＜0.05). Intravascular ultrasound (IVUS) was performed in 34patients. Plaque formation was found in LAD by IVUS in 17 (50 %) patients. No significant difference in CFVR was found between the patients without plaque formation (3. 11±0. 49) and those with plaque formation (2. 76±0.53, P=0. 056). It is suggested that TTDE with contrast enhancement provides reliable measurement of APV and CFVR in the distal LAD. The early stage of atherosclerosis could be detected by IVUS, which may be normal in angiography. CFVR is impaired in patients with history of hypertension compared with that in patients without history of hypertension.

Clinical Experience of LINAC-based Stereotactic Radiosurgery for Angiographically Occult Vascular Malformations / 대한방사선종양학회지

PURPOSE: To establish the role of stereotactic radiosurgery (SRS) for the treatment of patients with angiographically occult vascular malformation (AOVM). MATERIALS AND METHODS: Eleven patients (12 lesions) with AOVM were treated with linear accelerator-based SRS between February 1995 and December 1999. A magnetic resonance imaging of each patients showed well-circumscribed vascular lesion with reticulated core of heterogeneous signal intensity and peripheral rim of low signal intensity. SRS were performed with the median peripheral dose of 16 Gy (range 13~25). A single isocenter was used with median collimator size of 14 mm (range 8~20) diameter. RESULTS: With a median follow-up period of 42 months (range 12~56), rebleeding occurred in 3 AOVMs at 5, 6 and 12 months after SRS but no further bleeding did. Two patients experienced radiation-induced necrosis associated with permanent neurologic deficit and one patient showed transient edema of increased T2 signal intensity. CONCLUSION: SRS may be effective for the prevention of rebleeding in AOVM located in surgically inaccessible region of the brain. Careful consideration should be needed in the decision of case selection and dose prescription because the incidence of radiation-induced complications is too high to be accepted.

Analysis of Angiographically Unrecognized, Incidental Microaneurysm during Aneurysmal Operation

OBJECT: Microaneuryms were unvisible in angiograms and incidentaly detected during operation. Increasing the frequency of endovascular surgery, they have dangerous risk during procedure. So we analyzed the unvisible reason and report operation method. MATERIAL AND METHOD: Twenty-six cases of angiographically unrecognized microaneurysm were operated from January 1993 to May 1998. They consisted of 3.8% of 684 operated cases of intracranial aneurysms at the same period. The most common site of angiographically unrecognized microaneurysm was the internal carotid artery(11 cases): one arose from the posterior communicating artery, 9 from the anterior choroidal artery, 1 from the internal carotid artery bifurcation. RESULT: According to the intraoperative findings, we analyzed the possible reasons why these microaneurysms were not visible in the pre-operative angiograms; 19 cases in low type, 4 cases in hidden type, 3 cases in sandwiched type. We performed direct aneurysmal neck clippings in 9 cases and wrap-clip reinforcements in 8 cases, wrappings in 9 cases. CONCLUSION: We have to consider that angiographically unrecognized microaneurysm may be found during the direct operation of intracranial aneurysm and also during the endovascular surgery. Also, the wrapping technique is found to be less secure and needs regular follow-up angiography.

Three-Dimensional Computed Tomographic Angiography(3-D CTA) in Acute Subarachnoid Hemorrhage: A Case Report

In almost one in six patients with spontaneous subarachnoid hemorrhage(SAH) no lesion responsible for the bleed will be found by cerebral angiography. Current management strategies include repeat cerebral angiography after a period of 1-8 weeks during which a number of these patients will rebleed with considerable morbidity and even mortality. We report the case of a 51-year-old female patient with spontaneous SAH. Brain computed tomography (CT) demonstrated localized focal hematoma in the basal frontal interhemispheric fissure suggesting the presence of an anterior communicating artery(ACoA) aneurysm. Cerebral angiography was incomplete because of severe arther-osclerosis of left internal carotid artery and findings were negative. Cerebral three-dimensional computed tomographic angiography(3-D CTA) performed the next day showed a small aneurym arising from the ACoA. This was confirmed at surgery. It is suggested that 3-D CTA, guided by the CT findings, probably is useful in the diagnosis of patients with acute SAH and has a place in the management of patient with SAH of "unknown etiology" before repeat catheter angiography is undertaken.

The Results of Gamma Knife Radiosurgery for Vascular Lesions of the Brainstem

The optimal management of lesions located in the brainstem(BS) is problematic. As an alternative to microsurgical resection, stereotactic radiosurgery employing the Gamma unit has been used to manage BS lesions, and this can provide relatively safe and effective management. This study describes our experience with 17 patients who underwent Gamma Knife radiosurgery(GKR) for vascular lesions of the brainstem between June 1989 and May 1996. Six of these had BS arteriovenous malformations(AVMs). The minimal radiation dose to the margin of AVMs ranged from 15 to 25Gy(mean, 18.9Gy). Four of six cases were partially obliterated, and on follow-up angiography, one small AVM was seen to be completely obliterated. Twelve months after GKR, one patient experienced a temporary neurologic deficit due to the effects of radiation and another patient, who had a large AVM, showed a permanent deficit as a direct result of treatment. There have been no instances of hemorrhage after GKR and all the patients are still alive. GKR was used to manage 11 patients with angiographically occult vascular malformations (AOVMs) of the BS. The periphery of the lesions received a radiosurgical dose of between 12 and 20Gy(mean, 15.5Gy). In four patients, the lesions became smaller, but in one, an increase was seen. In the remaining six, size change was not documented. One patient's neurological deficit worsened, though that might be related not to GKR but to non-fatal post-GKR rebleeding. At seven months, one patient developed a temporary neurologic deficit in association with perilesional edema that resolved over time. Three patients experienced post-GKR rebleeding, and none died during the follow-up period. We believe that GKR is an excellent option for patients with BS AVMs: when the risks of microsurgery are deemed too high, it is a course of action which seems reasonable. GKR does not, though, appear to obliterate AOVMs as effectively as it does AVMs. To assess the long-term effectiveness of the technique on these lesions, longer follow-up intervals will, however, be required.

Clinical Characteristics of Angiographically Occult and Histologically Confirmed Intracranial Vascular Malformations

The medical records of 30 patients with histologically confirmed and angiographically occult intracranial vascular malformations(AOVM), who underwent surgery between May 1988 and May 1993, were reviewed retrospectively to determine whether their radiological and clinical characteristics are helpful in differential diagnosis. Histological diagnoses were cavernous angioma(CA) in 17 cases, arteriovenous malformation(AVM) in nine, venous angioma in one and unclassified vascular malformation in three. The most common initial presenting mode was intracranial hemorrhage(ICH ; 18 cases, 60.0%), followed by seizure(11 cases, 33.3%) and headache(two cases, 6.6%). CA, once it had bled, tended to bleed repeatedly, and this occurred before surgery in seven of nine cases of CA presenting with ICH. On CT scan, calcification was observed only in CA(two cases). On MRI images obtained in 28 patients, a mottled density mass with or without adjacent ICH(ten of 16 CA's) and multiple lesions(three of 16 CA's) were pathognomonic for CA, while single stage ICH(two of eight AVM's) and signal void(three of eight AVM's) were observed only in cases of AVM. Findings of MRI such as multiple stage hemorrhage, low signal intensity rim or edema around the lesion were not helpful in differential diagnosis of the histological type of lesions. After enhancement with gadolinium, one case of AVM and another of venous angioma showed a serpentine pattern of enhancement. In 29 cases, the results of surgery were excellent ; there was no mortality and morbidity in only one case. In conclusion, CA, once it had bled, tended to rebleed and MRI was helpful in the differential diagnosis of AOVM's. MRI findings such as a mottled density mass or multiple lesions were pathognomonic for CA, while single stage hemorrhage or signal void were findings of AVM.

Diagnosis and Treatment of Brain Stem Hemorrhage Caused by Angiographically Occult Vascular Malformation(AOVM)

In cases of symptomatic AOVM of the brainstem, there is a great risk of progressive morbidity caused by repetitive hemorrhage, and the condition can even be fatal. To establish the optimum method of management of this condition, we investigated 15 patients treated between January 1991 and January 1996. Seven lesions were located in the pons, three in the medulla, three in the midbrain, and one each at the pontomedullary and pontomesencephalic junction. Surgery was performed in six cases in which the lesions were close to the dorsal pial surface of the brainstem ; the histological diagnosis was five cases of cavernous angioma and one of arteriovenous malformation. Nine patients with surgically inaccessible lesions, deep seated or located in the midbrain, were treated by gamma knife radiosurgery. All patients who underwent surgery showed neurologic improvement, and among those who underwent radiosurgery, the outcome was favorable. For symptomatic lesions located in the dorsal pial surface of the pons or medulla, surgical resection is the treatment of choice, and prevents further neurological disability and rehemorrhage. For the best possible outcome, intraoperative sonography and electrophysiologic monitoring are mandatory. Gamma knife radiosurgery can be employed in selected cases in which lesions are deep-seated and inaccessible and associated with repeated hemorrhage and progressive neurologic deficit.

Stereotactic Gamma Knife Radiosurgery for the Treatment of Angiographically Occult Vascular Malformations(AOVMs)

In recent years, an increasing number of patient with AOVMs have been recognized using MRI. When an AOVM is located in a region associated with an unacceptable surgical risk, stereotactic radiosurgery offers an alternative treatment. We treated 21 patients with AOVM using gamma knife radiosurgery from June, 1990 to December, 1993 at Asan Medical Center. The indications for radiosurgery were as follows:1) Patients who had episodes of hemorrhage from a lesion that had the characteristic images of AOVM in MRI. 2) Patients who had seizures and the focus of these seizures corresponded to the lesions. 3) Patients were excluded if the lesions were located superficially or were accessible to microsurgery. Nine patients presented with hemorrhages and twelve with seizures. The marginal dose was ranged from 10 to 25 Gy at or above the 50% isodose line. Of eight patients followed 12 months or less after radiosurgery, two patients had improved neurologic deficits and one had decreased the seizure frequency with mediciation. Among seven patients followed 12-24 months, MRI showed a reduction of the lesion in one patient and no change in five patients. One patient had perifocal edema. In two patients with seizures, one patient was seizure free without medication and one patient was controlled with medication. In six patients between 24 and 44 months, two patients had smaller lesions and three patients had perifocal edema. Among four patients who had seizures, one patient was seizure free without medication and three had decreased the seizure frequency with medication. Postoperative complications developed two patients, but one patient showed improvement of neurologic deficits after a short period of steroid medication. Stereotactic radiosurgery offers a treatment to a selective patients with intracranial AOVMs.

Angiographically Occult Cerebral Vascular Malformations

In order to obtain more accurate pathological diagosis of the angiographically occult vascular malformations(AOVM) of the brain in the future and to examine the clinical, and radiological characteristics and management outcome of the AOVM, the authors retrospectively reviewed the 30 cases of AOVM in which patients were treated at our instituition during the past 11-year period. The pathological specimens were reexamined, and the lesions were reclassified according to the strict histopathological criteria. The clinical characteristics, radiological features, the difference between the clinical and pathological diagnosis and the management results were studied. There were 15 males and 15 females. The mean age at the time of diagnosis was 31 years, ranging from 3 months to 74 years. The clinical diagnosis were arteriovenous malformation(AVM) in 18 cases, cavernous angioma in 11 and mixed lesion in 1. The pathologic diagnosis was AVM in 14 cases, cavernous angioma in 2, and unclassified lesion in 12. The common presenting symptoms were hemorrhage(53.3%), seizure(20.0%) and mass lesions(20.0%). Twenty four lesions were located at the supratentorial region, 4 at cerebellum and 2 at pons. Most of the lesions were revealed as high density masses with minimal or no contrast enhancement on CT and a core of mixed signal intensity with a peripheral low signal intensity rim on T2-weight MRI. Preoperative clinically significant recurrent hemorrhages were noted in 8 cases and one of them showed marked deterioration of the neurological functions a result of recurrent hemorrhage. Twenty-eight patients underwent surgery and all except one improved neurologically. Six patients initially presented with seizure showed improvement in seizure frequency after operation. One patient who had the lesion at the pons was managed by a radiosurgery and one patient who refused surgery was managed by a conservative method. The conservatively managed patient and another patient who was not found AVM at the hematoma cavity during initial operation rebled about 2 years later following diagnosis and surgery. Thse findings suggest that the complete microsurgical excision, which prevents rebleeding and suppresses seizure activity, represents the treatment of choice for patients with clinically symptomatic AOVM. Avoiding the injury of the vascular mass, obtaining sufficient biopsy specimen during surgery, together with careful histopathological observation of operative specimens through complete clinical-radiological-pathological context are necessary to obtain more accurate pathological diagnosis.

Angiographically Occult Vascular Malformations of the Brain: Report of Three Cases

The authors experience 3 cases of angiographically occult vascular malformation(AVOM) of the brain during the last 3 months in 1990. All cases were diagnosis of either operative or pathological finding and were associated with intracerebral hemorrhage. The authors recommend that surgery should be considered even to those angiographically negative intracerebral hemorrhage cases, once clinical features are highly suggestive of AOVM. Surgery can be an effective and define therapy for these entities, which are prone to cause recurrent hemorrhage and persistent neural deficits.

Exploratory Craniotomy on the Angiographically Cryptic Aneurysms

The 121 nontraumatic subarachnoid hemorrhage patients who showed mainly subarachnoid hemorrhage without considerable intracerebral hematoma on C.T. finding admitted at Kyungpook National University Hospital for recent 1 year, were evaluated the exact causes of hemorrhage with variable diagnostic methods including 4-vessels cerebral angiography. Even with full studies of repeated 4-vessels cerebral angiography, 8 patients remained idiopathic cases without the clear causes. Out of 8 patients, authors selected 3 cases who had firm history of spontaneous subarachnoid hemorrhage, revealing some evidence of aneurysmal bleeding characteristics on brain C.T. scannings and cerebral angiographic findings, and operated on them for the perfect treatment with confirming the cause of bleeding. The operation called for treatment by clipping and coating on the aneurysmal sacs found in all the 3 patients.