Transcranial Doppler monitoring during percutaneous transluminal aortic valvuloplasty

Cerebral blood flow was studied in 12 elderly patients with severe calcific aortic stenosis by means of transcranial Doppler sonography (TCD) during percutaneous transluminal aortic valvuloplasty (PTAV). In 8 of these 12 patients duplex sonography revealed a stenosis of the internal carotid artery (ICA) exceeding 50%. Frequency spectra of 10 patients showed a satisfactory quality and were analyzed. In 7 subjects balloon inflation was well tolerated and systolic blood pressure did not drop below 75 mmHg. In these patients, whether they had a stenosis of the ICA or not, blood flow velocity in the middle cerebral artery (MCA) did not decrease to a critical level. The authors defined "critical" as a reduction of mean blood flow velocity in the MCA exceeding 50% or a decrease below 35 cm/sec. Three patients showed a rapid decrease of systolic aortic pressure below 75 mmHg. In these subjects mean blood flow velocity in the MCA dropped to levels below 35 cm/sec. Deflation and retraction of the balloon resulted in a rapid increase of systemic blood pressure and flow velocity in the MCA. This report demonstrates TCD to be a useful monitoring method of determining residual perfusion in patients with aortic stenosis during PTAV.     

一侧颈内动脉重度狭窄或闭塞后前交通动脉开放对另一侧颅内外动脉血流动力学的影响

目的研究一侧颈内动脉（ICA）颅外段重度狭窄（狭窄率为70％～99％）或闭塞后,前交通动脉（ACoA）开放对另一侧颅内、外动脉血流动力学的影响。方法选择一侧ICA颅外段重度狭窄或闭塞,另一侧ICA颅外段正常或狭窄率〈50％（简称相对正常侧）的患者228例,其中ACoA未开放者115例,开放者113例。采用彩色多普勒血流显像（CDFI）测量双侧ICA顿外段近段管径、收缩期峰值流速（PSV）、舒张期末流速（EDV）,血管阻力指数（RI）;经颅多普勒（TCD）测量双侧大脑中动脉（MCA）、大脑前动脉（ACA）的PSV,EDV及血管搏动指数（PI）。分析ACoA开放对相对正常侧ICA、MCA、ACAm流动力学的影响。结果①ACoA未开放组和开放组的相对正常侧的ICA颅外段管径差异尤统计学意义。ACoA开放组相对正常侧ICA的PSV、EDV均高于未开放组（P=0．000）,RI值低于未开放组（P=0．001）。②ACoA开放组相对正常侧的MCA、ACA的PSV和EDV均高丁未开放组（P=0．000）,PI值低于未开放组,但两组间仅ACA的PI差异有统计学意义（P=0．007）。③相关性分析显示,相对正常侧MCA和ACA的平均血流速度与ICA颅外段的平均血流速度呈正相关关系（r=0．587,r=0．346,P=0．000）。结论一侧ICA颅外段重度狭窄或闭塞时,ACoA的开放直接影响另一侧ICA颅外段及MCA、ACA的血流动力学变化。     

The impact of different spectral Doppler criteria on the proportion of high-grade internal carotid artery stenosis in patients undergoing duplex scanning

AIM: To investigate the impact of different spectral Doppler criteria on the proportion of high-grade ICA stenosis in patients undergoing carotid artery duplex scanning. MATERIAL AND METHODS: Duplex scans of 4,548 internal carotid arteries (ICA) in 2,349 patients were retrospectively analyzed. The following different criteria were applied for each scan for definition of ICA stenosis > or = 70%: Criteria I=ICA peak systolic velocity (PSV) > 130 cm/sec and ICA end-diastolic (EDV) > 100 cm/sec, Criteria II=PSV ICA/common carotid artery (CCA) ratio > 4, Criteria III=ICA PSV > or = 230 cm/sec, Criteria IV=ICA PSV > 230 cm/sec and/or ICA EDV > or = 100 cm/sec and/or PSV ICA/CCA ratio > or = 3.2. RESULTS: The frequency of detecting a > or = 70% ICA stenosis with criteria I, II, III, and IV were 5.5%, 6.8%, 8.4%, and 9.6%, respectively (p < 0.05). CONCLUSION: The use of various duplex criteria significantly affected the number of scans receiving a diagnosis of ICA stenosis of > or = 70%.     

Validation of a new noninvasive method (contrast-enhanced transthoracic second harmonic echo Doppler) for the evaluation of coronary flow reserve: comparison with intracoronary Doppler flow wire.

OBJECTIVES: We tested the hypothesis that coronary flow reserve (CFR) in the left anterior descending coronary artery (LAD) as assessed by a new noninvasive method (contrast-enhanced transthoracic second harmonic echo Doppler) is in agreement with CFR measurements assessed by intracoronary Doppler flow wire. BACKGROUND: Contrast-enhanced transthoracic second harmonic echo Doppler is a novel noninvasive method to detect blood flow velocity and reserve in the LAD. However, it has not yet been validated versus a gold-standard method. METHODS: Twenty-five patients undergoing CFR assessment in the LAD by Doppler flow wire were also evaluated by contrast-enhanced transthoracic Doppler to record blood flow in the distal LAD at rest and during hyperemia obtained by adenosine i.v. infusion. In five patients CFR was evaluated twice (before and after angioplasty). RESULTS: As a result of the combined use of i.v. contrast and second harmonic Doppler technology, feasibility in assessing coronary flow reserve equaled 100%. The agreement between the two methods was high. In fact, in all but five patients the maximum difference between the two CFR measurements was 0.38. Overall, the prediction (95%) interval of individual differences was -0.69 to +0.72. Reproducibility of CFR measurements was also high. The limits of the agreement (95%) between the two measurements were -0.32 to +0.32. CONCLUSIONS: Coronary flow reserve in the LAD as assessed by contrast-enhanced transthoracic echo Doppler along with harmonic mode concurs very closely with Doppler flow wire CFR measurements. This new noninvasive method allows feasible, reliable and reproducible assessment of CFR in the LAD.     

Ultrasound velocity criteria for carotid in-stent restenosis.

OBJECTIVE: To examine duplex ultrasound (US) criteria for carotid in-stent restenosis (ISR). BACKGROUND: Carotid artery stent (CAS) placement is an alternative to surgery for the treatment of carotid stenosis in high surgical risk patients. US is the primary method used to follow carotid stent patency. This study investigates US velocity measurements in carotid ISR. METHODS: Two hundred sixty consecutive patients with CAS placement from June 2000 to June 2004 were followed with serial US. ISR was determined by using the standard US velocity criteria for nonstented carotid artery using peak systolic velocity (PSV), end-diastolic velocity (EDV), and internal carotid artery to common carotid velocity ratio (ICA/CCA ratio). Patients suspected of having carotid ISR > or =50% by US, underwent invasive angiography with stenosis graded by NASCET criteria. Results were compared to patients with nonstented carotid artery stenosis using Two-tailed Student's t-test. RESULTS: PSV and ICA/CCA ratio increased to a greater degree in ISR. In 50-69% stenotic arteries, the mean ICA/CCA ratio was 2.76 +/- 0.7 in the ISR group compared to 2.04 +/- 0.3 in the nonstented carotid group (P < 0.05). In > or =70% stenotic arteries, there were increases in PSV (520 +/- 93 vs. 362 +/- 60, P < 0.05) and ICA/CCA ratio (7.58 +/- 2 vs. 4.51 +/- 1.3, P < 0.05) in ISR versus nonstented carotid arteries, respectively. CONCLUSION: PSV and ICA/CCA ratio in ISR increased to a greater extent for angiographic stenosis > or =50%. PSV 240 cm/sec and ICA/CCA ratio 2.45 are optimal thresholds for > or =50% ISR, and PSV 450 cm/sec and ICA/CCA ratio 4.3 are optimal thresholds for > or =70% ISR.     

非增殖期糖尿病视网膜病变患者眼血流动力学改变

目的　探讨非增殖期糖尿病视网膜病变(non-proliferativediabeticretinopathy,NPDR)对视网膜中央动脉(centralretinalartery,CRA)、静脉(centralretinalvein ,CRV)血流动力学影响。方法　用彩色多普勒超声(colorDopplerflowimaging,CDFI)检测5 6例(1 0 8只眼)非增殖期糖尿病视网膜病变患者的视网膜中央动脉、静脉血流状态,并与40例(80只眼)正常人的视网膜中央动脉、静脉血流进行比较。5 6例非增殖期糖尿病视网膜病变患者并作眼底荧光素血管造影(fundusfluoresceinangiography,FFA)检查。结果　NPDR组与对照组相比,CRA的收缩期血流峰速(peaksystolicvelocity,PSV) ,舒张末期流速(enddiastolicvelocity ,EDV) ,平均流速(meanvelocity ,Vm)均降低,搏动指数(Pulseindex,PI)和阻力指数(resistanceindex,RI)均增高,但CRV的收缩期血流峰速,舒张末期流速,平均流速均增高。结论　非增殖期糖尿病视网膜病变患者CRA的血流速度降低,CRV血流速度增加,视网膜循环阻力升高,视网膜血液供应不良,CDFI检测对DR早期诊断有一定意义。     

彩色多普勒超声对双侧颈内动脉狭窄血流速度高估的研究

目的探讨彩色多普勒超声（CDU）与经颅多普勒超声（TCD）联合评价双侧颈内动脉狭窄后一侧颈内动脉（ICA）狭窄率为70％～99％或闭塞时,对另一侧的ICA（狭窄率为50％～69％）血流动力学的影响。方法连续纳入2005年6月_2011年6月由彩色多普勒血流显像（CDFI）与TCD联合筛查、DSA证实的双侧ICA狭窄（一侧颈内动脉狭窄率为70％～99％或闭塞,另一侧为50％-69％）的患者102例作为研究组（A组）,同期选择单侧ICA狭窄率为50％～69％、对侧正常的患者89例为对照组（B组）。比较两组患者中狭窄率为50％～69％狭窄侧的ICA和大脑前动脉（ACA）的收缩期峰值流速（PSV）、舒张期末流速（EDV）、血管阻力指数（RI）和血管搏动指数（PI）的差异。并根据TCD和DSA检测的结果,将A组分为前交通支开放组（A1组54例）与未开放组（A2组48例）,进一步比较两组间中狭窄率为50％～69％狭窄侧ICA、ACA血流动力学参数的差异及血流动力学变化的相关性。结果①A组患者中狭窄率为50％～69％侧ICA、ACA的PSV、EDV高于B组（均P〈0．05）,RI及PI值较B组降低（P=0．001,P=0．000）。②A1组中狭窄率为50％～69％狭窄侧ICA、ACA的PSV、EDV均高于A2组（均P〈0．01）,但A1组ICA的RI值及ACA的PI均低于A2组（P=0．000,P=0．000）,差异均有统计学意义。@ICA的PSV、EDV与ACA的呈正相关（r=0．327、r=0．422,P=0．007、P=0．000）。结论当一侧ICA狭窄率为70％～99％,狭窄率为50％～69％狭窄侧ICA的流速测值明显高于实际病变程度的诊断标准。前交通支开放是双侧ICA狭窄的血流动力学变化的基础,双侧ICA狭窄程度的判断应结合颅内外血流动力学变化进行综合评价。     

超声对单侧颈内动脉严重狭窄或闭塞时颅内动脉血流动力学变化的研究

目的:分析并评价单侧颅外段颈内动脉(ICA)严重狭窄(≥70%)或闭塞时颅内侧支循环建立的情况。方法:彩色多普勒显像(CDFI)筛选出单侧颅外段ICA严重狭窄或闭塞患者42例,应用经颅彩色多普勒(TCCD)评价颅内主要动脉的血流动力学变化,并经数字减影血管造影术(DSA)检查结果证实。结果:1.与DSA比较:TCCD探测前交通动脉(AcoA)和眼动脉(OA)具有较高的敏感性、特异性,对AcoA探测的价值最大,其次是后交通动脉(PcoA)。2.AcoA的开放与卒中的发生呈负相关。3.患侧大脑中动脉(MCA)的收缩期峰值流速(PSV)及搏动指数(PI)值均较健侧明显减低(P<0.05)。卒中组和短暂性脑缺血发作(TIA)组患侧OA的PI值明显低于健侧(P<0.05)。结论:CDFI和TCCD检测可综合分析颅内主要动脉的血流动力学变化,准确、可靠及无创地评价颅内侧支循环的情况,对单侧ICA严重狭窄或闭塞患者的治疗和预后的判断具有重要的临床价值。     

Coronary artery blood flow velocity non-invasively measured using a vessel-tracking pulsed Doppler system

A newly-developed noninvasive method was used to measure left coronary blood flow during phantom experiments. Two techniques were used in which: (1) the sample position can always be set in a fluctuating vessel using a wall echo-tracking method with a phase-locked-loop, and (2) the Doppler reference signal was generated separately synchronous with the wall echo signal. These techniques were combined, using a commercially available pulsed Doppler apparatus (SSH-40B: Toshiba). Basic experiments were performed using a blood vessel phantom to verify the validity of these systems. Blood flow velocity in the fluctuating tube could be measured clearly using a vessel-tracking method. The blood flow velocity of the left anterior descending artery was measured in three normal subjects and in seven patients from the third intercostal space along the left sternal border. The velocity pattern was characterized by a crescendo-decrescendo shape in diastole. The peak velocity which appeared in diastole ranged from 19 to 69 cm/sec, with no difference by disease entity. However, in all cases, the blood flow velocity signals were marred by extraneous signals, making it impossible to measure blood flow velocity during systole. Further improvement of the system is mandatory in order to use this flowmeter clinically.     

Transthoracic Doppler echocardiographic analysis of phasic coronary blood flow velocity in hypertrophic cardiomyopathy.

OBJECTIVE: To use transthoracic Doppler echocardiography to assess coronary blood flow non-invasively in patients with hypertrophic cardiomyopathy. DESIGN: High frequency transthoracic Doppler echocardiography was used to assess resting phasic coronary velocity patterns in patients with hypertrophic cardiomyopathy and to define the relation between coronary flow patterns and clinical, echocardiographic, and haemodynamic manifestations of this condition. SETTING: A tertiary referral cardiothoracic centre. METHODS: Fifteen patients (10 men and five women, mean (SD) age 49 (10.3) years) with asymmetric hypertrophic cardiomyopathy underwent high frequency (5 MHz) transthoracic Doppler echocardiographic assessment of the left anterior descending coronary artery. In addition, standard two dimensional echocardiography was performed. The results were compared with 16 normal participants (nine men and seven women, mean age 61.2 (10.7) years) who had no evidence of cardiac disease. RESULTS: Biphasic diastolic predominant coronary artery blood velocity profiles were obtained in all patients and controls. Systolic peak blood velocity and velocity time integral were significantly reduced in the hypertrophic cardiomyopathy group compared with controls (11.3 (15.8) cm/s and 1.09 (1.78) cm v 20.5 (13.1) cm/s and 4.23 (2.80) cm, respectively, P < 0.05). A reversed pattern of systolic blood flow velocity was found in three patients with severe anterior wall and septal hypertrophy. During diastole there was prolongation of the diastolic acceleration (203 (53) ms v 110 (60) ms in controls, P < 0.05) and deceleration times (487 (200) ms v 210 (90) ms in controls, P < 0.05). There was no significant difference between those with and without symptoms or a left ventricular outflow tract gradient. CONCLUSIONS: Patients with hypertrophic cardiomyopathy have abnormal systolic and diastolic coronary flow profiles at rest when measured by transthoracic echocardiography.     

Contrast-enhanced transthoracic second harmonic echo Doppler with adenosine: a noninvasive, rapid and effective method for coronary flow reserve assessment.

OBJECTIVES: The purpose of this study is to evaluate the feasibility in detecting blood flow in the left anterior descending coronary artery (LAD) using transthoracic color Doppler (CD) imaging (in both second harmonic and fundamental mode) along with contrast enhancement and to verify if this new noninvasive method along with adenosine is safe, rapid and effective in assessing coronary flow reserve (CFR). BACKGROUND: Feasibility of contrast-enhanced transthoracic Doppler recording (in both second harmonic and fundamental mode) of blood flow velocity in the LAD has not been assessed. Adenosine has a greater vasodilator potency and more favorable kinetics than dipyridamole and thus it can be more suitable for assessing CFR in conjunction with this method. METHODS: Sixty-one patients with angiographically patent LAD underwent CD (both in fundamental and harmonic mode) as well as color-guided pulsed wave (PW) Doppler recording of blood flow velocity in the distal LAD before and after intravenous contrast injection. A second group of patients (n = 77), undergoing coronary angiography, was submitted to transthoracic contrast-enhanced PW Doppler recording of blood flow velocity in the LAD using harmonic CD as a guide, at rest and during adenosine-induced hyperemia. RESULTS: Harmonic CD along with echo contrast consistently improved blood flow detection in the LAD; the success rate in detecting flow of optimal quality was 88% with this approach, whereas it was 11% and 16% with CD in fundamental mode, respectively, before and after contrast. Pulsed wave Doppler results paralleled those of harmonic CD (p < 0.001 contrast harmonic vs. fundamental). In the second group of patients coronary angiography revealed 0% to <40% stenosis in 24 patients (group I), > or =40% to < or =75% in 17 patients (group II) and >75% stenosis in 34 patients (group III). There was a significant difference in CFR among the three groups of patients; CFR for peak diastolic velocity was (mean +/- SD): 2.88+/-0.7 (group I), 2.09+/-0.5 (group II) and 1.51+/-0.5 cm/s (group II) (p < 0.05 group I vs. both group II and group III; p < 0.05 group II vs. group III). The whole examination took less than 10 min. CONCLUSIONS: Contrast-enhanced second harmonic Doppler recording of blood velocity in the LAD is highly feasible and in combination with adenosine it is a rapid, safe and effective method for assessing CFR ratio.     

应用经胸冠状动脉血流显像技术评价支架术前后冠脉血流储备

目的采用经胸多普勒超声心动图冠状动脉血流显像技术观察支架术前后冠状动脉血流速度的变化,评价其对冠状动脉血流储备（CFR）的影响。方法22例冠心病患者(男18例,女4例),平均年龄（53.2±6.7）岁。对狭窄的冠状动脉行经皮冠状动脉腔内成形术（PTCA）后各置入一枚支架。分别于木前、术后72h内采用经胸多普勒冠状动脉血流显像技术记录狭窄远端静息舒张期血流峰速(r-Vd)、注射潘生丁及等长握力实验时最大舒张期血流峰速(d-Vd)及CFR。结果22例患者行支架术均获成功,狭窄率由术前(83.5±8.9)%,降至术后(5.2±9)%(P<0.05)。20支冠脉获得理想多普勒频谱（检出率90.9％）;支架术后r-Vd较术前r-Vd有增加趋势,但无统计学意义;术后静脉注射潘生丁后最大d-Vd及CFR均较术前明显增加［（0.92±0.22)m/svs(0.52±0.18)m/s,2.94±1.16vs1.88±0.40,P均<0.01］。30％患者术后CFR仍<2.0,此组与CFR≥2.0患者组比较,支架术后r-Vd明显增高［(0.45±0.19)m/svs(0.27±0.12)m/s,P<0.05］。少数患者(约18%,4／22)术前出现心绞痛,头昏等不适,静注氨茶碱或(和)含化硝酸甘油可迅速缓解。结论支架术能明显增加冠状动脉血流储备。采用经胸多普勒冠脉血流显像技术结合潘生丁、握力试验是一可行的无创性评价冠心病患者冠脉血流储备及介入治疗疗效的新方法。     

Thyroid vascularity is increased in patients with active acromegaly

OBJECTIVE: To determine whether acromegalic patients have increased thyroidal vascularity and blood flow on colour flow Doppler sonography (CFDS). DESIGN: Prospective study of consecutive patients. PATIENTS: Twenty-four acromegalic patients (11 men, 13 women, age 49 +/- 9 years); 38 patients with nontoxic goitre (NTG; 12 men, 26 women, age 50 +/- 7 years); 36 normal subjects (controls; 16 men, 20 women, age 46 +/- 9 years). Among acromegalic patients, 10 had active, untreated disease (Acro-U), seven were in remission after surgery (Acro-R), seven had active disease under treatment with somatostatin analogues (SMSa) (Acro-SA) (Sandostatin LAR, 20 mg, every 28 days). MEASUREMENTS: CFDS pattern and intrathyroidal peak systolic velocity (PSV) were determined by a colour Doppler system with a 7.5-MHz linear transducer. PSV measurements were made at the level of the intrathyroidal arteries (normal values 3.8 +/- 1.0 cm/s). Thyroid volume was calculated by the ellipsoidal model. Assays included measurements of serum GH, IGF-I, free T4, free T3, TSH, antithyroglobulin (anti-Tg) and antithyroperoxidase (anti-TPO) antibodies, TSH-receptor antibodies (TRAb). RESULTS: Serum GH (+/- SD) and IGF-I (+/- SD) levels were: Acro-U: GH 26 +/- 31 microg/l, IGF-I 783 +/- 299 microg/l; Acro-SA: GH 15 +/- 25 microg/l, IGF-I 366 +/- 212 microg/l; Acro-R: GH 1.3 +/- 1.0 microg/l, IGF-I 241 +/- 99 microg/l. To convert values for serum GH to mU/l multiply by 2.6; to convert values for serum IGF-I to nmol/l multiply by 0.13075. All controls had CFDS pattern 0 (absent vascularity or minimal spots); among NTG patients, 36 had pattern 0 and two had pattern I (parenchymal blood flow with patchy uneven distribution). Five patients with acromegaly had pattern 0, 12 had pattern I and seven pattern II (mild increase of colour flow Doppler signal with patchy distribution). Among the five acromegalic patients with pattern 0, three were Acro-R and two were Acro-SA. Among patients with pattern I, six were Acro-U, two were Acro-SA and four were Acro-R. Among patients with pattern II, four were Acro-U and three Acro-SA; two patients of the latter group had elevated serum IGF-I under SMSa treatment. Intrathyroidal PSV was 3.8 +/- 1.0 cm/s in controls, 4.0 +/- 1.1 cm/s in NTG, 7.4 +/- 0.8 cm/s in Acro-U, 4.9 +/- 1.3 cm/s in Acro-SA treatment and 4.5 +/- 1.0 in Acro-R. (Acro-U vs. Acro-SA, P = 0.0003; vs. Acro-R, Controls, or NTG, P < 0.0001). PSV values in Acro-SA were higher than those observed in NTG or controls (P = 0.05, P = 0.01, respectively); PSV values in Acro-R did not differ from those in NTG or controls. Intrathyroidal PSV values were correlated with serum IGF-I (r = 0.73, P < 0.0001) and, although less strongly, GH levels (r = 0.54, P = 0.01). Goitre was present in 19 of 24 patients; diffuse in three and nodular in 16. Thyroid function was normal in all subgroups of acromegalic patients. Anti-Tg, anti-TPO antibodies and TRAb were negative in all subjects. CONCLUSIONS: Patients with active acromegaly have increased intrathyroidal blood flow (colour flow Doppler sonography pattern II, increased peak systolic velocity values); this was not observed in the large majority of patients under treatment with somatostatin analogues and in any patient in remission. Accordingly, colour flow Doppler sonography and peak systolic velocity measurements may be considered an additional useful peripheral parameter for rapid assessment of the activity of acromegaly.     

超声检测大脑中动脉慢性闭塞患者脑血流与脑梗死的相关性

目的探讨大脑中动脉慢性闭塞(CMCAO)患者大脑前动脉(ACA)脑膜支代偿(LMA)对脑梗死大小的影响,分析大脑中动脉(MCA)流速与脑梗死面积的相关性。方法回顾性连续纳入2014年6月至2016年6月延边大学附属医院神经内科35例和首都医科大学宣武医院神经内科的CMCAO患者74例,对所有患者采用经颅多普勒超声(TCD)和(或)经颅彩色多普勒超声(TCCS)诊断为一侧CMCAO而对侧MCA正常,并经DSA证实。根据DSA显示ACA有无脑膜支,分为LMA组49例及无LMA组(NLMA)60例。采用TCCS和(或)TCD测量,记录患侧与健侧MCA的收缩期峰值流速(PSV)及平均流速(MFV),并计算健侧、患侧PSV比值(PSV_(健侧)/PSV_(患侧))。根据磁共振扩散加权成像(DWI)检查结果分为脑组织正常、腔隙性脑梗死、中小面积脑梗死及大面积脑梗死4级,采用秩和检验比较LMA组与NLMA组脑梗死面积的差异,并采用Spearman秩相关分析患侧MCA的血流参数与脑梗死面积的相关性。结果 (1)两组患者的患侧与健侧MCA的PSV、MFV及PSV_(健侧)/PSV_(患侧)差异均无统计学意义(均P0.05)。(2)NLMA组中卒中者占90.0%(54例),明显高于LAM组71.4%(35例),两组间差异有统计学意义(P0.05);LMA组DWI以腔隙性脑梗死为主(51.0%,25例),NLMA组多以中小面积脑梗死为主(45.0%,27例),并且大面积脑梗死发生率(21.7%,13例)高于LMA组(4.1%,2例),两组差异有统计学意义(P0.01)。(3)NLMA组患者脑梗死面积与MCA的PSV呈中度负相关(r=-0.736,P0.01),并随PSV_(健侧)/PSV_(患侧)的升高而增加,呈高度正相关(r=0.849,P0.01)。结论 CMCAO患者ACA的LMA状态与脑梗死严重程度相关,患侧MCA血流速度的减低与脑梗死面积存在明显相关性。     

Genetic and environmental effects on carotid flow velocities: An international twin study

Introduction

Altered carotid blood flow velocities (CFV) have a complex background but the underlying genetic contribution is still unclear. We sought to evaluate the influence of genetics, shared and unshared environmental components on individual differences of CFV.

Methods

193 healthy twin pairs, 126 monozygotic (MZ) and 67 dizygotic (DZ) (mean age 53 ± 14 years) recruited in Italy, in the United States and in Hungary underwent bilateral color-coded Doppler flow assessment of the common carotid artery (CCA) and of the internal carotid artery (ICA) in order to assess the peak systolic (PSV) and end diastolic (EDV) velocities. Means of bilateral CFV values were used in the analysis.

Results

Age- and country-adjusted intra-class correlations were higher in monozygotic than in dizygotic pairs for mean PSV of the ICA indicating a heritability of 63%. Unique environmental factors contributed to 37% of ICA PSV. With regards to the mean PSV and EDV of the CCA, and EDV of the ICA, heritability analysis indicated no discernible role for genetic components, while the contributions of shared and unshared environmental factors ranged between 56% and 63%, and between 37% and 44% adjusted for age and country, respectively. Mean ICA/CCA ratio was driven by unique environmental factors (82%) with modest heritability (18%).

Conclusions

Our study showed that the heritability of ICA PSV and ICA/CCA ratio is moderate, while the findings do not support heritability of other investigated CFV values. Environmental effects account for a moderate to major portion of the variance. These findings support the value of early ultrasound screening as well as the prevention of modifiable environmental factors in case of altered carotid flow velocities.     

Extracranial carotid Doppler ultrasound evaluation of cerebral blood flow volume in COPD patients

OBJECTIVE: Doppler ultrasound of extracranial internal carotid artery (ICA) and vertebral artery (VA) were performed and total cerebral blood flow volume (tCBFV) was evaluated in chronic obstructive pulmonary disease (COPD) patients. CBFV changes due to blood gas changes were also evaluated. METHODS: Bilateral ICA and VA have been examined with 7.5 MHz linear array transducer in COPD patients. Angle-corrected time averaged flow velocity and cross-sectional areas of vessels have been measured. Flow volumes and tCBFV have been calculated. Flow velocities and waveform parameters have been measured. RESULTS: tCBFV, anterior-posterior CBFVs, left-right ICA flow volumes, bilateral ICA and VA cross-sectional areas and left ICA peak-systolic velocity were significantly higher in COPD patients than control group. Among COPD patients tCBFVs were highest in hypoxemic-hypercapnic ones, and lowest in normocapnic ones. Bilateral VA flow volumes, bilateral ICA (except left ICA V(ps)) and VA flow velocities and waveform parameters were not different in COPD patients compared with control group. When compared among the subgroups of COPD patients, there were no significant differences for all parameters. CONCLUSION: tCBFVs were found to be significantly higher in COPD patients. This increment which is probably due to balancing the oxygen deficit is low with hypoxemia and high with hypercapnia and hypoxemia. Particularly, bilateral ICA and VA cross-sectional area changes and increased left ICA V(ps) were considered as the main reason for increased tCBFV in COPD patients.     

Transcranial Doppler sonography for blood flow velocity measurement during pharmacological tests

Transcranial Doppler sonography, using a 2 MHz pulsed Doppler system, is suitable for non-invasive continuous monitoring of middle cerebral artery blood flow velocity during pharmacological studies. Methodological problems, and factors affecting cerebral blood flow have to be discussed (vasomotor spontaneous changes, intracranial blood pressure, blood viscosity, heart rate, vascular risk factors, etc.). Arguing from a previous study in 28 subjects (11 healthy volunteers, 8 hypertensive patients, 9 patients with middle cerebral artery stenosis), showing the hypotensive action of Nifedipine, without significant decrease of cerebral blood flow in 83% of cases, we emphasize the advantages and limits of this new non-invasive method for cerebral blood flow monitoring.     

The effect of angiotensin II type-1 receptor gene polymorphisms on doppler blood flow parameters of carotid and brachial arteries in patients with myocardial infarction

BACKGROUND: Genetic influence on Doppler blood flow parameters of carotid and brachial arteries (BA) is uncertain. We investigated the relationship between the angiotensin II type-1 receptor (AT1R) gene polymorphism and the blood flow characteristics of common carotid arteries (CCA) and BA by color Doppler ultrasound (CDUS) in patients with a first anterior acute myocardial infarction (AMI). METHODS AND RESULTS: Sixty-seven patients (15 women and 52 men), aged 25-77 years, with anterior AMI were studied. The AT1R genotypes were established. Based on the polymorphism of the AT1R, they were classified into three groups: AT1R AA genotype (Group1, n = 42 patients), AT1R AC genotype (Group 2, n = 17 patients), and AT1R CC genotype (Group 3, n = 8 patients). Peak-systolic velocity (PSV) and end-diastolic velocity (EDV) of right and left CCA, PSV of right BA, and intimal-medial thickness (IMT) of both CCA were measured by CDUS. All results evaluated statistically. The AT1R genotypes were distributed as follows: 63% AA, 25% AC, and 12% CC. PSV of BA and both CCA were higher in patients with CC and AC than AA (P < 0.05). Also, IMT of both CCA were also higher in the same groups (P < 0.05). CONCLUSIONS: Our results suggest that AT1R gene polymorphism influences Doppler blood flow parameters of both BA and CCA, and IMT of CCA. Although further studies are required.     

Carotid artery fibromuscular dysplasia: Ultrasound and CT imaging

An asymptomatic 54‐year‐old Caucasian female was found to have a right carotid bruit located high in the cervical region. Carotid duplex ultrasound revealed carotid intimal disease with increased Doppler flow in the mid‐distal right internal carotid artery (RICA) with color Doppler turbulence in the distal RICA. Computed tomography angiography (CTA) revealed a typical “string‐of‐beads” sign in both distal internal carotid artery (ICAs), diagnostic of fibromuscular dysplasia (FMD). While often not diagnostic, carotid duplex ultrasound may yield clues as to diagnosis of FMD with elevated Doppler velocity in the distal carotid, turbulent distal carotid flow, and possibly a “string‐of‐beads” sign. An “S‐curve” distal ICA is associated with FMD and may warrant further evaluation. Magnetic resonance angiography and CTA appear to be better for diagnosis of carotid FMD. The typical “string‐of‐beads” may be readily identified. While invasive angiography is considered the “gold standard” for diagnosis of carotid FMD, it is infrequently required. Generally, invasive angiography is performed in symptomatic patients in planning for interventional therapy.