Coronary flow reserve in patients with chest pain and normal coronary arteries.

BACKGROUND--Many studies have shown that coronary flow reserve is reduced in patients with chest pain and angiographically normal coronary arteries. The methods used to assess coronary blood flow have varied, but in nearly all reports dipyridamole has been used to bring about vasodilatation. This study was designed to assess whether the apparent impairment of coronary flow reserve seen with dipyridamole could be reproduced with either papaverine or adenosine, which induce maximum coronary blood flow by different mechanisms. METHODS--25 patients with chest pain and angiographically normal coronary arteries were studied with an intracoronary Doppler flow probe and quantitative angiography to determine epicardial coronary artery area, coronary blood flow velocity, coronary flow reserve, and coronary vascular resistance index (CVRI, the ratio of resistance after intervention to basal resistance). All patients received papaverine 8 mg. Eight patients with positive exercise tests received intracoronary papaverine (8 and 10 mg), intracoronary adenosine (6, 20, 60 micrograms), and high-dose intravenous dipyridamole (0.84 mg/kg). RESULTS--The velocity ratio (peak after intervention: baseline) (mean (SEM)) after 8 mg papaverine was 3.3 (0.2) (n = 25) and the coronary flow reserve was 4.1 (0.3) (n = 25). There were no differences between patients with a positive (n = 16) or negative (n = 9) exercise test. In eight patients coronary flow reserve was measured after increasing doses of papaverine, adenosine, and dipyridamole. Coronary flow reserve was 4.5 (0.3) with papaverine, 4.8 (0.3) with adenosine, and 3.5 (0.4) with dipyridamole (p = 0.08 v papaverine and adenosine). CVRI was 0.22 (0.01) with papaverine, 0.21 (0.02) with adenosine, and 0.29 (0.03) with dipyridamole (p < 0.05 v papaverine, p = 0.09 v adenosine). CONCLUSIONS--These results indicate that measurement of coronary flow reserve and CVRI in patients with chest pain and normal coronary arteries depends on the pharmacological stimulus. Normal values were obtained with papaverine in all patients, irrespective of the exercise test response. In patients with a positive exercise test significantly lower values were obtained with dipyridamole than with papaverine, or adenosine. The reported impairment of coronary flow reserve in patients with angina and normal coronary arteries may reflect the variability in response to different pharmacological agents. The mechanism underlying this variability is unknown, but may involve an abnormality of adenosine metabolism in the myocardium.     

冠状动脉造影正常的胸痛患者冠状动脉血流储备功能研究

目的 :评价冠状动脉血流储备 (CFR)功能的测定对阐明冠状动脉造影正常患者的胸痛机制的临床作用。方法 :4 0例冠状动脉造影正常的胸痛患者分为非心脏病组、X综合征组及高血压组 ,采用TIMI计帧法测定注射罂粟碱前后相关冠状动脉血流帧数的变化 ,并计算CFR。结果 :X综合征组用药前后血流速度均慢于非心脏病组 (P <0 .0 5 ,P <0 .0 1) ,高血压组静息血流速度快于非心脏病组 (P <0 .0 5 )。非心脏病组的CFR范围为2 .0～ 2 .8,X综合征组及高血压组的CFR低于非心脏病组 (P <0 .0 1)。结论 :TIMI计帧法可用于CFR的测定 ,X综合征及高血压患者CFR降低 ,原因可能与冠状动脉小血管的充血反应能力下降和 (或 )基础冠状动脉血流的增加有关     

Diminished coronary flow velocity reserve and aortic distensibility in elderly patients with chest pain and negative coronary angiograms

BACKGROUND AND AIMS: Aging is a dominant process that alters vascular stiffness, endothelial function and coronary flow regulation. The objective of our work was to assess simultaneously the elastic properties of the descending aorta and coronary flow velocity reserve (CFR) during the same transesophageal echocardiography (TEE) in elderly patients. METHODS: The following patients with normal epicardial coronary arteries were compared: 30 subjects under 55 years of age (group 1) and 17 patients over 55 years (group 2). A complete TEE examination was carried out in all patients, and the following aortic elastic properties were calculated from aortic diameter and blood pressure data: aortic elastic modulus [E(p)] and Young's circumferential static elastic modulus [E(s)]. Doppler evaluation of left anterior descending coronary flow velocity was performed in resting conditions and after administration of 0.56 mg/Kg dipyridamole over 4 min. Peak coronary flow velocities were measured at the 6th minute at maximum vasodilation. CFR was estimated as the ratio of hyperemic to basal peak diastolic coronary flow velocities. RESULTS: Peak hyperemic diastolic coronary flow velocities were significantly decreased (139.1+/-35.6 cm/s vs 105.7+/-39.7 cm/s, p<0.01) in patients >55 years. CFR was decreased (2.67+/-1.05 vs 2.13+/-0.56, p<0.05), whereas E(p) (in 103 mmHg, 0.59+/-0.49 vs 0.94+/-0.65, p<0.05) and E(s) (in 103 mmHg, 5.70+/-4.30 vs 8.47+/-5.14, p<0.05) were increased in patients >55 years. A correlation was found between CFR and E(p) (r=-0.20, p<0.05). CONCLUSIONS: CFR and aortic distensibility are altered in elderly patients. There is a relationship between these functional parameters.     

Coronary flow reserve, esophageal motility, and chest pain in patients with angiographically normal coronary arteries

PURPOSE AND METHODS: To ascertain the relative prevalence of abnormalities of coronary flow reserve and esophageal function in patients with chest pain despite angiographically normal coronary arteries, 87 patients underwent invasive study of coronary flow reserve and, during the same week, esophageal testing. RESULTS: Sixty-three of the 87 patients (72%) demonstrated abnormalities of coronary flow reserve, as evidenced by an increase in coronary resistance during the stress of rapid atrial pacing after administration of ergonovine 0.15 mg intravenously (1.33 +/- 0.36 mm Hg.minute/mL), compared with pacing at the same heart rate before ergonovine administration (1.10 +/- 0.33 mm Hg.minute/mL). This higher coronary vascular resistance occurred in the absence of significant epicardial coronary artery luminal narrowing. Fifty-seven of these 63 patients (90%) with a coronary vasoconstrictor response to ergonovine described their typical chest pain during pacing stress, compared with only six of 24 patients (25%) who demonstrated no coronary flow abnormality (p less than 0.001). After administration of dipyridamole 0.5 to 0.75 mg/kg intravenously to 65 patients, the 48 patients with ergonovine-induced vasoconstriction had a significantly higher minimum coronary resistance, compared with the 17 patients without a coronary vasoconstrictor response to ergonovine (0.65 +/- 0.21 versus 0.47 +/- 0.13 mm Hg.minute/mL, p less than 0.03). Twenty of 87 patients (23%) had abnormal esophageal motility [nutcracker esophagus (11), nonspecific motility disorder (seven), and diffuse esophageal spasm (two)], including 16 of the 63 patients (25%) with abnormal coronary flow reserve. Twenty-four (28%) patients experienced their typical chest pain during motility testing, but only five of these patients met criteria for abnormal esophageal motility. Nine of 75 patients tested (12%) had their typical chest pain during Bernstein testing, and 18 of 38 patients (47%) tested had their typical chest pain provoked by intraesophageal balloon distention. CONCLUSIONS: Seventy-one of 87 patients (82%) with anginal-like chest pain and normal epicardial vessels in our series had a disorder of either coronary flow reserve, esophageal motility, and/or reproduction of typical chest pain during acid infusion. Of interest, chest pain was commonly encountered during cardiac and esophageal testing (85% of patients), regardless of the ability to demonstrate an abnormality of coronary flow reserve or abnormal esophageal function. This suggests that pain experienced by these patients may be a consequence of myocardial ischemia, esophageal dysfunction, abnormal visceral nociception, or a combination of any or all of these entities.     

Pattern of exercise-induced ST change is related to coronary flow reserve in patients with chest pain and normal coronary angiogram

OBJECTIVE: To evaluate the usefulness of exercise treadmill test in determining the true microvasculature-induced ischemia, we compared the pattern of ST depression with coronary flow reserve (CFR) using transthoracic Doppler echocardiography (TTE) in patients with chest pain and normal coronary angiogram. DESIGN: Fifty-nine subjects (M/F=21:38, mean age 55+/-9 years) with chest pain and normal coronary angiogram underwent maximal symptom-limited exercise treadmill test (ETT). CFR was estimated with TTE and dipyridamole. Patients with a history of acute myocardial infarction, regional wall motion abnormalities, hypertrophic cardiomyopathy, ejection fraction less than 50%, or primary valvular heart disease were excluded from this study. RESULTS: No ST change was observed in 20 of 59 (34%) patients, up slope depression was observed in 20 (34%), flat depression in 13 (22%), and down slope depression in 6 (10%). Eleven of thirty nine (28%) exercise positive patients had decreased CFR <2.1. CFR was 3.1+/-0.6 in group with no ST change, 3.1+/-0.6 in group with up slope depression, 2.1+/-0.6 in group with flat depression (p<0.05 versus group with no change and group with upslope depression, respectively), and 2.0+/-0.4 in group with down slope depression (p<0.05 versus group with no change and group with up slope depression, respectively). Flat to down slope depression of ST change during ETT had sensitivity of 58% and specificity of 95% for predicting CFR <2.1. CONCLUSION: Flat and down slope depression of ST segment during ETT might increase the sensitivity and specificity to detect the true microvasculature-induced ischemia that is defined as CFR less than 2.1 in patients with chest pain and normal coronary angiogram.     

Coronary reserve and exercise ECG in patients with chest pain and normal coronary angiograms.

BACKGROUND. Coronary vasodilator reserve is reduced in some patients with a history of chest pain and angiographically normal coronary arteries. ECG changes suggestive of myocardial ischemia during exercise also can be demonstrated in a subset of these patients. METHODS AND RESULTS. We have investigated the correlation between coronary vasodilator reserve, assessed with 13N-labeled ammonia and positron emission tomography, and the ECG during exercise stress in 45 patients with a history of chest pain, angiographically normal coronary arteries, and a negative ergonovine test. ST segment depression on the ECG during exercise was present in 29 of 45 patients. Mean resting left ventricular blood flow was 1.04 +/- 0.22 ml.min-1.g-1; it increased to 1.32 +/- 0.47 ml.min-1.g-1 (p less than 0.01 versus baseline value) during atrial pacing and to 2.52 +/- 0.96 ml.min-1.g-1 (p less than 0.01 versus baseline value) after dipyridamole (0.56 mg/kg i.v.). No regional flow defects could be demonstrated in any patient during pacing or after dipyridamole. Myocardial flows after dipyridamole, however, did not show a normal frequency distribution (Kolmogorov-Smirnov test), and two patient populations could be identified. Twenty-nine (67%) patients had a mean left ventricular flow of 3.02 +/- 0.33 ml.min-1.g-1 after dipyridamole (range, 2.13-5.46 ml.min-1.g-1), and 14 (33%) patients had a mean flow of 1.48 +/- 0.29 ml.min-1.g-1 (range, 1.06-2.04 ml.min-1.g-1, p less than 0.01 versus the "high-flow group"). CONCLUSIONS. Approximately one third of patients in our series showed a reduced coronary vasodilator reserve. Although 12 of 14 patients in the "low-flow group" had ST segment depression during exercise stress, 16 of 29 patients in the high-flow group also had ST segment depression during exercise stress. Therefore, despite a good sensitivity (86%) in identifying patients with a blunted increment of coronary flow, the ECG response during exercise stress appears to have a rather low specificity (45%). This suggests that factors other than reduced coronary reserve and myocardial ischemia may play a role in the genesis of the ST segment depression in these patients.     

不同性别非冠状动脉阻塞性胸痛患者冠状动脉血流储备特点及影响因素研究

目的 探讨不同性别非冠状动脉阻塞性胸痛患者冠脉血流储备的特点及影响因素.方法 入选2011年10月至2017年9月于北京大学第三医院心内科就诊的302例影像学检查证实冠脉狭窄＜50％的胸痛患者,行经胸多普勒超声心动图测定冠状动脉左前降支的冠脉血流储备(CFR),比较男女性CFR特点.结果 研究对象平均年龄(60.1±9...     

Dynamic limitation of coronary vasodilator reserve in patients with dilated cardiomyopathy and chest pain

Twenty-six patients with dilated cardiomyopathy and angiographically normal coronary arteries, 12 of whom gave a history of anginal chest pain, underwent noninvasive and invasive hemodynamic study. During treadmill exercise testing, patients with a history of angina demonstrated worse effort tolerance (7.4 +/- 4.9 versus 13.6 +/- 5.1 minutes, p less than 0.005) and a lower end-exercise systolic blood pressure-heart rate product (17.9 +/- 3.4 versus 23.6 +/- 4.9 mm Hg.beats/min x 10(3), p less than 0.005) compared with patients without a history of angina. During rapid atrial pacing after ergonovine, 0.15 mg intravenously, 11 of the 12 patients with a history of angina experienced their typical chest pain, in contrast to only 1 of 12 patients without a history of angina. The angina group, compared with the nonangina group, had significantly lower great cardiac vein flow (118 +/- 24 versus 160 +/- 43 ml/min, p less than 0.01), and higher coronary resistance (0.87 +/- 0.21 versus 0.66 +/- 0.25 mm Hg.min/ml, p less than 0.05), significant widening of the arterial--great cardiac vein oxygen difference and a significant fall in cardiac index during pacing. Further, ergonovine resulted in higher coronary resistance during pacing in the angina group compared with pacing alone (+0.16 +/- 0.16 mm Hg min/ml, p less than 0.01), in the absence of significant reduction in epicardial coronary artery luminal diameter. After dipyridamole, 0.5 to 0.75 mg/kg intravenously, to 21 patients, the 7 patients with a history of angina had significantly lower flow (149 +/- 37 versus 218 +/- 73 ml/min, p less than 0.05) and higher coronary resistance (0.59 +/- 0.09 versus 0.43 +/- 0.17 mm Hg.min/ml, p less than 0.05) than did the nonangina group. It is concluded that patients with dilated cardiomyopathy and chest pain unrelated to epicardial coronary artery disease exhibit impaired vasodilator responses to both metabolic and pharmacologic stimuli, and an increased sensitivity to the vasoconstrictor effects of ergonovine. Whether these findings are of etiologic or long-term prognostic significance is unknown.     

Noninvasive coronary flow reserve assessed by transthoracic coronary Doppler ultrasound in patients with left anterior descending coronary artery stents

Noninvasive measurement of coronary flow reserve (CFR) (hyperemic/flow velocity ratio at rest) by transthoracic Doppler echocardiography showed normalization of flow in the left anterior descending (LAD) coronary artery early after stenting. We hypothesized that noninvasive CFR may reveal in-stent restenosis at follow-up. Therefore, we studied 134 patients, 0 to 72 months after successful proximal-middle LAD stenting, and 38 controls. LAD flow velocity was measured by transthoracic Doppler echocardiography during 90 seconds venous adenosine infusion (140 microg/kg/min). CFR was measured in diastole. According to angiography, patients who received stents were divided into 3 groups: group I, <50% LAD in-stent restenosis (n = 83); group II, nonsignificant (50% to 69%) LAD in-stent restenosis (n = 17); and group III, significant (> or = 70%) LAD in-stent restenosis (n = 34). LAD CFR was similar in group I and controls (2.90 +/- 0.58 vs 3.05 +/- 0.81; p = NS), it was slightly lower in group II (2.42 +/- 0.33) compared with controls and group I (p <0.001 vs both), and clearly abnormal (<2) in group III (1.38 +/- 0.48) compared with controls, and groups I and II (p <0.001). A CFR <2 had 91% sensitivity, 95% specificity, and 96% positive and 97% negative predictive values to detect significant stenosis in patients with LAD stents. Our data show that noninvasive Doppler assessment of CFR allows identification of significant LAD in-stent restenosis, based on a cut-off value of <2.     

Mechanisms of impaired coronary flow reserve in patients with aortic stenosis: transthoracic Doppler echocardiographic study

OBJECTIVES: Development of left ventricular hypertrophy in severe aortic stenosis is associated with coronary microcirculatory dysfunction, as demonstrated by impaired coronary flow reserve. Recently, coronary flow reserve can be assessed noninvasively by transthoracic Doppler echocardiography (TTDE). This study assessed the relationship between coronary flow reserve obtained by TTDE and the hemodynamic parameters and left ventricular mass index in patients with aortic stenosis. METHODS: Consecutive 29 patients (15 men, 14 women, mean age 72 +/- 11 years) with isolated mild to severe aortic stenosis were studied using TTDE to assess coronary flow reserve. Peak transvalvular pressure gradient across the aortic valve (peak AVG) and aortic valve area were measured by TTDE. Left ventricular mass index was measured by echocardiography. RESULTS: There were significant correlations between coronary flow reserve and peak AVG (r = -0.570, p = 0.001), left ventricular mass index (r = -0.620, p < 0.001), aortic valve area (r = 0.740, p < 0.001), and left ventricular rate pressure product (r = -0.660, p < 0.001). Multiple regression analysis showed that aortic valve area and peak AVG were independent factors for coronary flow reserve (p < 0.001, p = 0.048). CONCLUSIONS: Impairment of coronary flow reserve in patients with aortic stenosis is related to aortic valve area and peak AVG, rather than the degree of left ventricular hypertrophy.     

血流储备分数在指导冠状动脉多支病变治疗策略中的作用

目的评估冠状动脉造影筛选的冠状动脉多支病变与心肌缺血的关系,阐明血流储备分数（FFR）在指导冠状动脉多支病变治疗策略中的作用。方法纳入96例患者218处冠状动脉病变,根据FFR值分为两组,FFR〉0．80组（113处）及FFR≤0．80组（105处）。结果FFR≤0．80组冠状动脉直径狭窄程度更高[（66．2±10．5）％比（59．1±13．8）％,P〈0．001]、面积狭窄百分比更大[（87．3±7．7）％比（81．44-10．9）％,P〈0．001]、最小管腔直径更小[（0．86±0．36）mm比（1．18±0．49）mm,P〈0．001],上述指标与FFR值无明确相关（相关系数分别为r=-0．286,P〈0．001;r=-0．282,P〈0．001）。冠状动脉最小管腔直径与FFR值呈正相关（r=0．364,P〈0．001）。冠状动脉造影筛选的96例患者中,26例为三支病变,70例为双支病变;经FFR测量后,缺血相关的三支病变10例,两支病变29例,单支病变17例。QCA冠状动脉造影直径狭窄i〉70％,FFR〉0．80的病变为21处（9．6％）;QCA冠状动脉造影直径狭窄〈70％,FFR≤0．80的病变为53处（24．3％）。QCA冠状动脉造影直径狭窄1〉70％,FFR~〈0．80的病变为52处（23．9％）（Matches）;QCA冠状动脉造影直径狭窄〈70％,FFR〉0．80的病变为92处（42．2％）（Matches）。QCA冠状动脉造影面积狭窄I〉70％,FFR〉0．80的病变为89处（40．8％）（Mismatches）;QCA冠状动脉造影面积狭窄≥70％,FFR≤0．80的病变为105处（48．2％）（Matches）;QCA冠状动脉造影面积狭窄〈70％,FFR〉0．80的病变为24处（11．0％）（Matches）。结论FFR在指导冠状动脉多支病变治疗策略中具有重要意义,可显著降低缺血相关靶病变个数。     

阿托伐他汀对冠状动脉血流缓慢患者冠状动脉血流储备的影响

目的 探讨冠状动脉血流缓慢患者冠状动脉血流储备(CFR)的改变以及阿托伐他汀对这类患者CFR的影响.方法 入选有胸痛症状但冠状动脉造影结构正常的冠状动脉血流缓慢患者91例,分为治疗组(51例)和无治疗组(40例).治疗组给予阿托伐他汀20 mg治疗8周.另选26例冠状动脉造影正常且运动试验阴性的无心脏疾患者为正常对照组.治疗前后测定治疗组和无治疗组的血脂以及利用腺苷负荷超声记录左前降支远端血流频谱,并评价CFR.结果 (1)冠状动脉血流缓慢者接受阿托伐他汀8周治疗后总胆固醇(TC)和低密度脂蛋白胆固醇(LDL-C)较无治疗组及正常对照组明显减低[TC:(3.83±0.80)mmol/L比(5.30±1.18)mmol/L和(5.32±1.17)mmol/L,均P＜0.05:LDL=C:(2.26±0.64)mmol/L比(3.28±0.85)mmol/L和(3.30±0.82)mmol/L,均P＜0.05].(2)给予阿托伐他汀前,治疗组与无治疗组CFR(分别为2.32±0.30和2.25±0.33)均低于正常对照组(3.15±0.34,P＜0.05);8周后,治疗组冠状动脉血流速度(CFV)[(26.06±3.22)cm/s]较无治疗组[(29.02±3.36)cm/s]及治疗前静息状态[(28.43±3.40)cm/s]低(均P＜0.05),最大冠状动脉扩张状态CFV高于无治疗组和对照组[分别为(77.63±8.96)、(65.17±7.22)和(64.58±6.26)cm/s,P＜0.05],CFR低于治疗前和无治疗组(分别为3.07±0.29、2.28±0.35和2.32±0.30,P＜0.05),且与正常对照组差异均无统计学意义.结论 冠状动脉血流缓慢患者CFR明显减低,短期阿托伐他汀在调脂的同时可以有效改善其CFR.     

Cutaneous and coronary flow reserve in patients with microvascular angina.

Microvascular angina is characterized by exercise-induced angina in patients with normal coronary arteries and reduced coronary flow reserve. Recently, a generalized disorder of abnormal vascular reactivity in microvascular angina has been postulated. Therefore, coronary flow reserve was determined by the coronary sinus thermodilution technique and compared with the cutaneous flux ratio in 6 control subjects (group 1) and 12 patients with microvascular angina (group 2). Coronary flow reserve was calculated from maximal coronary flow after 0.5 mg/kg of dipyridamole divided by flow at rest. Cutaneous flow ratio was estimated by laser Doppler fluxmetry (right forearm) before and after 4 min of suprasystolic blood pressure occlusion. Coronary flow at rest was identical in the two groups, but after maximal vasodilation with dipyridamole, coronary flow was higher in group 1 than in group 2 (p less than 0.05). Coronary flow reserve differed significantly between the two groups (2.9 in group 1 and 1.3 in group 2; p less than 0.001). Cutaneous Doppler flux at rest was higher in group 1 than in group 2 (p less than 0.05). However, the hyperemic response was identical in both groups. It is concluded that the cutaneous flux ratio in patients with microvascular angina is not impaired. Local peripheral vasomotor tone appears to be increased in patients with microvascular angina because cutaneous flow at rest is reduced. Thus, a generalized disorder of abnormal vascular reactivity cannot be confirmed in patients with microvascular angina.     

Detection of impaired coronary flow reserve in coronary artery disease using transthoracic echocardiographic assessment of coronary sinus blood flow

In order to establish whether coronary flow reserve (CFR) can be measured by transthoracic echocardiography (TTE) with pulse wave Doppler echocardiography, 14 patients with coronary artery disease (CAD) and 12 normal subjects were studied. Coronary sinus blood flow was measured at rest and 2 minutes after intravenous injection of 0.56 mg/kg dipyridamole (DP). CFR was calculated as the DP to rest flow ratio. Patients with CAD were found to have significantly decreased CFR when compared to normal subjects. These findings suggest that TTE may be useful in diagnosing CAD.     

Prognostic effect of coronary flow reserve in women versus men with chest pain syndrome and normal dipyridamole stress echocardiography

The aim of this study was to investigate the prognostic effect of coronary flow reserve (CFR) on left anterior descending artery (LAD) in women and men with chest pain of unknown origin and normal stress echocardiogram. The study population consisted of 1,660 patients (906 women, 754 men) with chest pain syndrome, no wall motion abnormality on echocardiogram at rest, and dipyridamole (up to 0.84 mg/kg over 6 minutes) stress echocardiogram negative for wall motion criteria. All had undergone stress echocardiography with combined evaluation of CFR on LAD by Doppler. A CFR value ≤2.0 was considered abnormal. Median duration of follow-up was 19 months (interquartile range 10 to 34). Abnormal CFR was assessed in 171 women (19%) and 147 men (19%, p = 0.80). During follow-up, 80 events (20 deaths, 13 ST-elevation myocardial infarctions, and 47 non-ST-elevation myocardial infarctions) occurred. In addition, 128 patients underwent revascularization and were censored. CFR ≤2.0 on LAD was independently associated with prognosis in women (hazard ratio [HR] 16.48, 95% confidence interval [CI] 7.17 to 37.85, p <0.0001) and in men (HR 6.23, 95% CI 3.42 to 11.33, p <0.0001). Antianginal therapy at time of testing (HR 2.11, 95% CI 1.14 to 3.90, p = 0.02) was also a multivariable prognostic predictor in men. Four-year event rate associated with CFR values ≤2.0 and >2.0 were, respectively, 27% and 2% in women (p <0.0001) and 42% and 8% in men (p <0.0001). In conclusion, decreased CFR on LAD is associated with markedly increased risk in women and men with chest pain syndrome and a normal result of dipyridamole stress echocardiography. Conversely, preserved CFR on LAD predicts excellent survival, particularly in women.     

Effects of atorvastatin on coronary flow reserve in patients with slow coronary flow

BACKGROUND: Statins improve endothelial functioning in patients with coronary artery disease and hypercholesterolemia, while substantially little is known about induced changes in myocardial microcirculation. However, although previous studies have suggested that microvascular abnormalities and endothelial dysfunction is responsible for slow coronary flow (SCF), there is no study investigating possible effects of statins on coronary microvascular function in patients with SCF. HYPOTHESIS: We prospectively investigated the effects of short-term lipid-lowering therapy with atorvastatin on coronary flow reserve (CFR) reflecting coronary microvascular function in patients with SCF assessed by transthoracic Doppler echocardiography (TTDE). METHODS: In an open clinical trial, CFR was studied in 20 subjects with SCF. TTDE was used to assess CFR at baseline as well as after 8 weeks of atorvastatin therapy. Coronary flow was quantified according to TIMI frame count (TFC). Coronary diastolic peak flow velocities were measured at baseline and after dipyridamole infusion. CFR was calculated as the ratio of hyperemic to baseline diastolic peak velocities. RESULTS: CFR was independently correlated with TFC. After 8 weeks of atorvastatin therapy, CFR values increased significantly (1.95 +/- 0.38 vs. 2.54 +/- 0.56, (p < 0.001). No change in hemodynamic parameters was noted during the entire study. The improvement in CFR was not correlated to the amount of lipid-lowering effect of atorvastatin. CONCLUSIONS: These findings suggest that short-term lipid-lowering therapy with atorvastatin improved CFR, which reflects coronary microvascular functioning in patients with SCF.     

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。