Long‐Term Prognostic Significance of Coronary Flow Velocity Reserve in Patients with Significant Coronary Artery Disease Not Involving the Left Anterior Descending Coronary Artery (Results from the SZEGED Study)

Objective: Coronary flow velocity reserve (CFR) by pulsed Doppler echocardiography is a useful hemodynamic index to evaluate the coronary microcirculatory dysfunction in the left anterior descending coronary artery (LAD). The present study was designed to evaluate the long‐term predictive value of CFR for mortality in patients with right (RC) and/or left circumflex coronary artery (CX) stenosis without epicardial LAD disease. Methods: A total of 49 patients with significant RC and/or CX stenosis were enrolled in this prospective follow‐up study. All patients had undergone coronary angiography demonstrating significant RC and/or CX stenosis without LAD disease and dipyridamole stress transoesophageal echocardiography as CFR measurement. Results: The success rate of follow‐up was 43 out of 49 (88%). During a mean follow‐up of 97 ± 29 months, 14 patients suffered cardiovascular deaths (12 sudden cardiac deaths and 2 strokes), and 1 patient died of pulmonal tumor. Patients who died during the follow‐up had significantly lower CFR values (1.85 ± 0.43 vs. 2.31 ± 0.57, P < 0.05). Using ROC analysis, CFR <2.09 had the highest accuracy in predicting cardiovascular survival (sensitivity 80%, specificity 57%, area under the curve 73%, P = 0.003). The logistic regression model identified only CFR as an independent predictor of survival (hazard ratio [HR] 6.26, 95% CI of HR 1.23–19.61, P = 0.024). Conclusions: Long‐term prognostic significance of CFR for the prediction of mortality has been demonstrated during a 9‐year follow‐up in patients with significant coronary artery disease not involving the LAD. (Echocardiography 2010;27:306‐310)     

Comparison of transthoracic Doppler echocardiography to intracoronary Doppler guidewire measurements for assessment of coronary flow reserve in the left anterior descending artery for detection of restenosis after coronary angioplasty

Transthoracic Doppler echocardiography (TDE) has been described as a feasible and accurate technique to noninvasively assess coronary flow reserve (CFR) in the left anterior descending artery (LAD). This study was designed to evaluate whether serial assessment of CFR in the LAD using TDE allows detection of restenosis after previously performed angioplasty. Thirty-three consecutive patients with single-vessel coronary artery disease of the LAD scheduled for angioplasty underwent assessment of coronary flow velocity at rest and during adenosine-induced hyperemia in the distal LAD using high-frequency TDE. CFR was calculated as the ratio of hyperemic to basal systolic/diastolic mean velocity. Investigations were performed before and immediately after angioplasty, and at the time of control angiography after 3 months. CFR results by TDE were compared with intracoronary Doppler guide wire measurements. Adequate pulse-wave Doppler signals to measure CFR were obtained in 30 patients (91%) using TDE. There was close correlation between echocardiographically and intracoronary derived CFR results (r = 0.80, 0.79, and 0.87 before angioplasty, early after, and at 3- month control angiography, respectively; p <0.001). Using a cut-off value of CFR < or =2.0 to identify significant coronary artery disease, TDE detected LAD restenosis with a sensitivity of 89% and specificity of 90%. Thus, high-frequency TDE is a feasible technique to noninvasively assess CFR in the LAD with results closely corresponding to invasive measurements. Defining a cut-off value of CFR < or =2.0, the technique has the potential to reliably detect LAD stenosis after coronary intervention.     

Diagnostic value of the 16-detector row multislice spiral computed tomography for the detection of coronary artery stenosis in comparison to invasive coronary angiography

OBJECTIVES: The aim of this study was to determine the diagnostic accuracy of 16-slice multislice spiral computed tomography (MSCT) of the coronaries and to provide data in a real clinical setting. Previous 16-slice MSCT studies presented data excluding patients with calcification, vessels of < 1.5 or 2 mm, and segments with impaired image quality. By including these data for 16-slice MSCT, a direct comparison with new data from 64-slice MSCT is possible. METHODS AND RESULTS: Sixty two patients with suspected or known coronary artery disease (CAD) were prospectively enrolled and underwent computed tomography angiography (CTA) and invasive coronary angiography (ICA). All vessels were evaluated for the presence of a significant coronary artery stenosis (>50%) using the American Heart Association (AHA) 15-segment model. From the evaluation of 917 segments, sensitivity, specificity, and positive and negative predictive value (NPV) (positive predictive value [PPV] and NPV) for the presence of relevant coronary stenosis were 73, 98, and 71 and 98% per segment and 94, 90, and 91 and 93% per patient, respectively. The influence of age, gender, body surface area (BSA), heart rate (HR), stents, and Ca(2+)-score value was analyzed. High Ca(2+)-score values were the only statistically significant predictor for impaired diagnostic accuracy. CONCLUSIONS: In summary, CTA with evaluation of all vessel segments in a broad spectrum of patients allowed accurate and fast noninvasive coronary artery evaluation, including evaluation of stented segments. These data are very similar to those published recently for 64-slice scanners.     

Clinical Outcome in Patients with Intermediate Stenosis of Left Anterior Descending Coronary Artery after Deferral of Revascularization on the Basis of Noninvasive Coronary Flow Reserve Measurement

Background: Several reports suggest that noninvasive measurements of coronary flow reserve (CFR) by use of echocardiography may support decision making in intermediate stenosis of the left anterior descending coronary artery (LAD). The aim of the present study was therefore to analyze the clinical outcome in patients with intermediate stenosis of LAD after deferral of coronary revascularization on the basis of noninvasive CFR measurement. Methods: the study population included 280 patients with intermediate LAD stenosis (50–70% by angiography) (62.2 ± 9.6 years). All the patients underwent transthoracic CFR assessment of LAD (after dipyridamole infusion) within 2 weeks from coronary angiography. If CFR of LAD was ≤ 2, PTCA was recommended; if CFR was > 2, medical treatment was chosen. Primary end points were cardiac death, myocardial infarction, coronary revascularization procedure, and unstable angina. Results: mean follow-up was 43 ± 11 months (range 12–52 months). In 150 patients (53.6%) (CFR ≤ 2), coronary artery revascularization was performed (PTCA group); the remaining 130 patients (46.4%) (CFR > 2) were medically treated (medical group). Survival from cardiac death was 94% in the PTCA group and 92.4% in the medical group (P = 0.56). As for all cardiac events, the Kaplan–Meier percentage survival from cardiac events was 88.3% in the PTCA group and 86.4% in the medical group (P = 0.36). Conclusions: even if CFR as a "stand-alone" diagnostic criterion suffers from several structural limitations, a combined strategy including also other clinical and instrumental measurements before undergoing interventional procedures could improve the cost–benefit practice, in particular, for the management of patients with intermediate LAD stenosis.     

64层螺旋CT血管成像在冠心病诊断中的应用

目的评价64层螺旋CT(MSCT)血管成像在冠心病诊断中的应用价值。方法选择80例冠心病或可疑冠心病患者行心电门控的MSCT冠状动脉成像,在特定工作站完成图像重建,并与冠状动脉造影结果对照,分析64层MSCT冠状动脉成像在诊断冠心病中的应用价值。结果80例患者中共1200个冠状动脉节段,其中1096个冠状动脉节段可供临床诊断分析,104(8．7%)个冠状动脉节段因图像质量差不能进行诊断分析。在所有可供分析的78例患者中MSCT诊断冠心病的敏感度、特异度、阳性预测值、阴性预测值和诊断准确度分别是96．1%、85．2%、92%和92．3%。1096个可供评价的冠状动脉节段中MSCT识别直径狭窄≥50%病变的敏感度、特异度、阳性预测值、阴性预测值分别为93．2%、89．3%、85．6%、95．2%和92．3%。结论64层MSCT冠状动脉成像对冠心病的诊断有良好的准确性。     

Diagnostic accuracy of computed tomography coronary angiography in routine practice

OBJECTIVES: The recent newer advances in computed tomography have dramatically changed our approach to imaging cardiac disease. This study sought to compare the diagnostic value of 16-multi-detector spiral computed tomography (MSCT) for detecting coronary artery stenosis. METHODS: A total of 88 consecutive patients (52 men, mean age 68 +/- 8 years) with atypical chest pain, stable angina or suspicion of ischaemia at stress test were studied by MSCT and invasive coronary angiography (ICA). The MSCT images and multiplanar reconstructions were analysed regarding the presence of > or =50% coronary artery lesion. RESULTS: All 88 scans obtained at a mean heart rate of 68 +/- 8 beats/min were interpretable. Sixteen coronary segments were evaluated in each patient. Of the 1320 segments examined, 148 (11%) showed poor image quality.A total of 150 significant lesions were detected using ICA, and 80 of 150 (53%) were detected by MSCT. Sensitivity, specificity, positive and negative predictive values were as follows: 53%, 97%, 68%, and 94%. Fifty-four patients had > or =50% coronary stenosis.The diagnosis was confirmed by MSCT in 42 patients and correctly ruled out in 30. By patient-based analysis, positive and negative predictive values were 91% and 71%. CONCLUSION: Although its specificity is high, the sensitivity of 16-slice MSCT for detecting > or =50% coronary stenosis in non-selected patients submitted to ICA is rather low suggesting that for daily practice the diagnostic value of this technique should be improved.     

Incremental diagnostic value of ultrasonographic assessment of coronary flow reserve with high-dose dipyridamole in patients with acute coronary syndrome

BACKGROUND: Coronary flow reserve (CFR) assessment by transthoracic Doppler echocardiography has been found to be useful in subjects with suspected coronary artery disease. An important clinical question is whether such technique can be successfully applied in patients admitted to the coronary care unit with an acute coronary syndrome to detect a significant left anterior descending (LAD) disease. METHODS: One hundred fifty-nine patients with acute coronary syndrome (93 patients with unstable angina, 66 with acute inferior or lateral myocardial infarction) were included in the present analysis. Patients underwent a high-dose dipyridamole stress (0.84 mg/kg) with combined assessment of CFR in the LAD and regional wall motion. Blood flow velocities were recorded in the mid-distal portion of the LAD using a digital ultrasonographic system and CFR was calculated as the ratio of hyperemia-induced peak diastolic velocity to resting peak diastolic flow velocity. All patients underwent coronary angiography and a significant LAD stenosis was classified for lumen narrowing > or = 70%. RESULTS: Adequate Doppler recordings in the LAD were obtained in 92% of patients. A contrast agent was used in the 39% of examinations. No major adverse reaction occurred in any patient. A receiving operating characteristic curve showed that a CFR value < 1.9 had a sensitivity of 85%, a specificity of 87%, a positive predictive value of 71%, a negative predictive value of 94% and a diagnostic accuracy of 86% for identifying a significant LAD stenosis. The area under the receiving operating characteristic curve computed for CFR was significantly higher than for wall motion score index (p < 0.001). In a stepwise forward, multiple logistic regression analysis, both CFR (OR = 4.8, 95% C.I. 3.7-5.3; p < 0.00001) and the wall motion score index for the LAD territory (OR = 4.2, 95% C.I. 2.6-6.8; p < 0.0001) were independent determinants of LAD stenosis > or = 70%. CONCLUSION: Early assessment of CFR by transthoracic Doppler echocardiography is feasible and safe and provides additional information to identify subjects with acute coronary syndrome and significant LAD stenosis.     

经胸彩色多普勒检测冠心病患者冠状动脉左前降支和右冠状动脉远端血流储备

目的评价经胸彩色多普勒超声心动图(TTDE)检测冠状动脉前降支(LAD)和右冠状动脉后降支(PDA)血流储备和开放程度的可行性。方法65例(男48例,女17例)连续临床诊断或疑似冠心病患者,平均年龄(58±14)岁,左室射血分数(49±8)%,用TTDE冠状动脉显像方式于心尖两腔切面显示LAD和PDA远端的血流,在基础状态和持续静脉注射腺苷(140μg·kg-1·min-1)情况下分别测定其冠状动脉血流储备(CFR),结果与冠状动脉造影对比。结果所有患者基础和充血状态LAD血流均得到显示(其中4例应用造影剂),55例患者PDA得到显示(5例应用造影剂),有2例患者PDA闭塞,因此LAD的检测成功率为100%(65/65),PDA的CFR检测成功率为87%(55/63),所有患者腺苷静脉注射时间均少于4min,CFR检测平均时间为(7.3±1.6)min。以CFR≤2.0和CFR≤1.8分别作为判断冠状动脉狭窄(≥50%)和显著狭窄(≥70%)的标准,准确性相近,诊断LAD和RCA狭窄的灵敏度、特异度和ROC曲线下面积分别为89%/93%,86%/84%,0.89/0.92,诊断显著狭窄的灵敏度、特异度和ROC曲线下面积分别为88%/89%,90%/83%,0.94/0.95。结论经胸多普勒超声心动图检测LAD和PDA成功率和诊断冠状动脉狭窄的准确性均较高,有重要临床价值。     

腺苷超声心动图与腺苷负荷心肌灌注显像诊断冠心病的价值

目的探讨腺苷超声心动图负荷试验(ASF)与腺苷负荷~(99m)Tc心肌灌注显像(Ad-SPECT)诊断冠心病的价值。方法选择临床拟诊断为稳定性心绞痛的住院患者86例,同期行ASE和Ad-SPECT单项及联合试验,观察腺苷静脉滴注后心率、血压及其不良反应发生情况。结果 86倒患者接受冠状动脉造影检查,阳性62例,阴性24例。ASF诊断冠心病的敏感性、特异性和准确度分别为74%、79%和76%,Ad-SPECT分别为87%、62%和80%,ASE及Ad-SPECT的联合平行试验敏感性、特异性和准确度分别为97%、63%和87%,联合系列试验分别为65%、88%和80%。联合平行试验的敏感性与各单项试验敏感性之间、联合系列试验的特异性与各单项试验特异性之间差异有统计学意义(P<0.05)。结论腺苷负荷试验安全、可靠,ASE及Ad-SPECT诊断冠心病特异性、敏感性均较高,联合试验可进一步提高诊断冠心病的价值。     

Transthoracic Doppler echocardiographic coronary flow imaging in identification of left anterior descending coronary artery stenosis in patients with left bundle branch block

Background: Conventional noninvasive methods have well‐known limitations for the detection of coronary artery disease (CAD) in patients with left bundle branch block (LBBB). However, advancements in Doppler echocardiography permit transthoracic imaging of coronary flow velocities (CFV) and measurement of coronary flow reserve (CFR). Our aim was to evaluate the diagnostic value of transthoracic CFR measurements for detection of significant left anterior descending (LAD) stenosis in patients with LBBB and compare it to that of myocardial perfusion scintigraphy (MPS). Methods: Simultaneous transthoracic CFR measurements and MPS were analyzed in 44 consecutive patients with suspected CAD and permanent LBBB. Typical diastolic predominant phasic CFV Doppler spectra of distal LAD were obtained at rest and during a two‐step (0.56–0.84 mg/kg) dipyridamole infusion protocol. CFR was defined as the ratio of peak hyperemic velocities to the baseline values. A reversible perfusion defect at LAD territory was accepted as a positive scintigraphy finding for significant LAD stenosis. A coronary angiography was performed within 5 days of the CFR studies. Results: The hyperemic diastolic peak velocity (44 ± 9 cm/sec vs 62 ± 2 cm/sec; P=0.01) and diastolic CFR (1.38 ± 0.17 vs 1.93 ± 0.3; P=0.001) were significantly lower in patients with LAD stenosis compared to those without LAD stenosis. The diastolic CFR values of <1.6 yielded a sensitivity of 100% and a specificity of 94% in the identification of significant LAD stenosis. In comparison, MPS detected LAD stenosis with a sensitivity of 100% and a specificity of 29%. Conclusions: CFR measurement by transthoracic Doppler echocardiography is an accurate method that may improve noninvasive identification of LAD stenosis in patients with LBBB.     

Detection of coronary restenosis after coronary angioplasty by contrast-enhanced transthoracic echocardiographic Doppler assessment of coronary flow velocity reserve

OBJECTIVES: This study sought to evaluate the diagnostic potential of contrast-enhanced transthoracic echocardiography (CE-TTE) during adenosine infusion, a noninvasive method for evaluating coronary flow reserve (CFR), in detecting restenosis after successful percutaneous transluminal coronary angioplasty (PTCA). BACKGROUND: Restenosis is the most important limitation of PTCA, and CFR can be impaired in patients with angiographically documented significant coronary stenosis. METHODS: We performed 6 +/- 2 months of follow-up of 53 patients after successful elective PTCA in the left anterior descending coronary artery (LAD). Coronary angiography was performed at the end of the planned follow-up period or even before, if clinically indicated. Thus, of the 53 patients, a total of 63 angiographic studies were performed; CE-TTE assessment of CFR was achieved before each of the 63 angiographic studies. RESULTS: Coronary angiography revealed the presence of restenosis (defined as >50% stenosis at a previous PTCA site) in 32 angiographic examinations (group A) and no coronary restenosis in the remaining 31 examinations (group B). Coronary flow reserve was significantly reduced in group A compared with group B (1.65 +/- 0.5 vs. 3.17 +/- 0.8, p < or = 0.001). A noninvasive CFR value < or = 2 was 93% specific and 78% sensitive for detecting significant restenosis, with positive and negative diagnostic accuracies of 92% and 80%, respectively. CONCLUSIONS: Noninvasive CFR assessment by CE-TTE is an accurate method of monitoring significant restenosis in the LAD when following up patients submitted to elective PTCA.     

Evaluation of flow in the left anterior descending coronary artery but not in the left internal mammary artery graft predicts significant stenosis of the arterial conduit

OBJECTIVES: The purpose of this study was to evaluate which Doppler-derived flow index best predicts new distal left anterior descending coronary artery (LAD) stenosis in patients with left internal mammary artery (LIMA) graft. BACKGROUND: The LIMA flow measurement has been proposed to assess graft function, but it may be misleading in case of new distal LAD stenosis and/or competitive flow from native LAD. Distal LAD coronary flow reserve (CFR: hyperemic/baseline peak flow velocity ratio) may be more appropriate. METHODS: The LIMA and distal LAD flow was measured by transthoracic Doppler echocardiography in 96 patients undergoing diagnostic/therapeutic coronary angiography, 7 +/- 4 years after cardiac bypass surgery. The LIMA flow indexes (systolic-to-diastolic peak velocity ratio [SDPVr] >1, diastolic time velocity integral fraction [DTVIf] <0.5, and CFR <2) and LAD CFR <2 were used to predict > or =70% new LAD stenosis. RESULTS: The LAD CFR <2 predicted new LAD stenosis, found in 21 of 77 patients without competitive flow from native LAD, with significantly higher diagnostic accuracy (98%) than LIMA flow indexes (SDPVr >1 = 61%, DTVIf <0.5 = 69%, and CFR <2 = 72%). The LIMA flow indexes were abnormal in 17 of 19 patients with competitive graft flow, but only 5 had graft restriction, and none had significant LAD stenosis. In a multivariate model of new distal LAD stenosis prediction, competitive flow from native LAD reduced the predictive role of LIMA but not of LAD CFR. CONCLUSIONS: In patients without competitive flow from native LAD, LAD CFR is more accurate for the detection of LAD stenosis than LIMA CFR. In patients with competitive graft flow, abnormal LIMA flow patterns and blunted LIMA CFR do not reflect downstream LAD flow as LAD CFR does.     

64排螺旋CT冠状动脉成像在冠状动脉病变诊断中的临床研究

目的探讨和评价64排螺旋CT（MSCT）在冠心病诊断中的有效性。方法选取在3周内行64排MSCT和冠状动脉造影（CAG）检查的临床可疑或确诊冠心病的患者（两项检查平均间隔时间9d）114例，其中男性62例，平均年龄65岁。将MSCT和CAG检查结果进行分析，管腔狭窄≥50％定义为明显狭窄。结果在114例患者中，CAG检出至少有1处明显狭窄的患者106例，其中单支病变占33％（38例），多支病变占60％（68例）。MSCT检出其中的104例（诊断准确度95％）。按节段分析，MSCT诊断冠状动脉明显狭窄的灵敏度、特异度、阳性预测值、阴性预测值分别为87％、96％、86％、96％。以各冠状动脉分析，MSCT诊断冠状动脉明显狭窄的灵敏度、特异度、阳性预测值、阴性预测值分别为96％、94％、95％、96％。MSCT与CAG在发现冠状动脉明显狭窄上差异无统计学意义（P〉0．05）。结论64排MSCT诊断冠状动脉狭窄的准确度较高，作为一种冠心病诊断的无创筛查手段，有广泛的临床应用价值。     

Diagnostic performance of 64-slice computed tomography coronary angiography to detect significant coronary artery stenosis

OBJECTIVE: We aimed to determine the diagnostic accuracy of 64-slice multi-slice computed tomography (MSCT) to detect significant coronary artery stenosis with comparison to conventional coronary angiography (CCA). METHODS: In 100 patients (70 men, average age 58 +/- 10 years and age range 31-75 years) scheduled to have conventional coronary angiography, MSCT was performed before catheterization (within 2 months). All patients were in sinus rhythm, able to hold breath for 15 seconds, and had serum creatinine levels < 1.5 mg/dl. MSCT scans were analysed by a radiologist and a cardiologist. Sensitivity, specificity, positive and negative predictive values for the detection of significant stenoses by MSCT in comparison with CCA were calculated on patient, vessel, and segmental bases. RESULTS: 64-slice computed tomography is able to detect significant coronary artery stenosis on a segmental basis with a sensitivity of 88% and specificity of 99% when compared with CCA. All patients with significantly stenotic coronary artery disease are correctly diagnosed. The presence of significant stenosis was correctly diagnosed by MSCT in 126 of 144 segments. Twelve non-significant lesions on CCA were overestimated by MSCT. On vessel-based analysis, the sensitivity and specificity of MSCT for detecting significant stenosis were 91% and 97%, respectively. CONCLUSION: Our results indicate that 64-slice computed coronary angiography is a reliable diagnostic modality for the detection of significant coronary artery stenosis in patients with sinus rhythm and scheduled to have CCA, but still has limitations of diagnostic performance on a per-segment and per-vessel basis.     

Diagnostic performance of 64-channel multislice computed tomography in assessment of significant coronary artery disease in symptomatic subjects

The recent development of 64-channel multislice computed tomography (MSCT) has resulted in noninvasive coronary artery imaging improvement. This study was conducted to determine the accuracy of 64-slice MSCT in a relatively unselected group of 143 patients with presentations suggestive of coronary artery disease, including those with unstable angina pectoris, who underwent both coronary computed tomographic angiography and invasive coronary angiography. No arrhythmia was considered an exclusion criterion except for atrial fibrillation or frequent extrasystoles. In patients with fast heart rates, a beta blocker was administered orally. Data were obtained using electrocardiography gated 64-slice MSCT. Computed tomographic angiography and invasive coronary angiography findings of each coronary segment were compared to determine the sensitivity, specificity, positive predictive value, and negative predictive value of MSCT in the detection of their normalcy or insignificant (<50% diameter decrease) stenosis versus significant (>or=50% diameter decrease) stenosis or total occlusion. In per-patient assessment, the calculated sensitivity, specificity, positive predictive value, and negative predictive value of MSCT were 96%, 67%, 91%, and 83%, respectively. These values in per-artery evaluation were 94%, 94%, 87%, and 97%, and corresponding values in per-segment analysis were 92%, 97%, 77%, and 99%, respectively. In conclusion, computed tomographic angiography has high diagnostic performance in the assessment of significant coronary artery disease in most patients in a daily routine practice, including those presenting with unstable angina pectoris symptoms.     

多排螺旋CT冠脉成像与冠脉造影对冠心病诊断的对比研究

目的初步评价多排螺旋CT（MSCT）在冠状动脉成像中的临床应用价值。方法18例疑诊冠状动脉狭窄患者行MSCT扫描,利用影像曲面重建,3D重建,了解冠状动脉病变情况,并与冠状动脉造影（CAG）对比。结果18例76支血管同时经MSCT和CAG成像。CAG发现狭窄27支,其中左前降支（LAD）病变11支,回旋支（LCA）病变3支,左主干（LMA）2支,右冠（RCA）病变9支,桥支病变2支。MSCT发现狭窄24支,其中LAD病变11支,LCA病变3支,LMA病变1支,RCA病变7支,桥支病变2支。MSCT与CAG结果相符的病变血管22支,MSCT成像的敏感性为82%（22/27）,特异性96%（47/49）。结论在控制心率的情况下MSCT可作为冠状动脉狭窄的一种无创筛选检查方法。     

64层螺旋CT血管成像与冠状动脉造影对冠心病诊断价值的对比研究

目的评价64层螺旋CT在冠状动脉造影方面的诊断价值。方法58例临床诊断或可疑冠心病患者行64层螺旋CT冠状动脉成像检查,分别对左主干、左前降支、回旋支和右冠状动脉及其分支的重建图像行影像学评价,所有患者均行常规选择性冠状动脉造影检查作为对照。结果58例患者共757(87.0%)节段的冠状动脉(血管直径≥1.5 mm)成像,638节段(84.3%)可用于多层螺旋CT和冠状动脉造影定量分析。冠状动脉造影共发现狭窄101节段,多层螺旋CT发现狭窄104节段,多层螺旋CT对冠状动脉狭窄诊断的敏感性为86.1%,特异性为96.8%。结论64层螺旋CT冠状动脉造影可作为诊断冠状动脉病变的一种无创筛选方法。     

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.     

腺苷负荷试验心肌灌注显像诊断冠心病的临床价值

目的　评价腺苷负荷试验心肌灌注显像诊断冠心病的准确性。方法　对 89例临床疑诊冠心病患者 ,分别静脉注射腺苷 ,剂量为 14 0 μg·kg-1·min-1,用药时间 6min(总剂量为 0 8mg/kg) ,注射过程中 ,行心电监测 ,观察患者的症状、血压和心率 ,于注射腺苷 3min末 ,静脉注射核素显像剂99mTc MIBI 92 5MBq ,1h后行心肌灌注断层显像 ,若显像异常 ,次日行静息心肌显像。所有患者行冠状动脉造影。结果　在 89例患者中 ,31例冠状动脉造影显示明显的冠状动脉狭窄病变 ,其中单支病变 10例 ,二支病变 11例 ,三支病变 10例。累及左前降支 2 8支 ,左回旋支 18支 ,右冠状动脉 16支 ,左主干 2支。腺苷负荷试验心肌灌注显像诊断冠心病的敏感性为 71%、特异性为 91%、阳性预测值81%、阴性预测值 84 %、准确性为 84 %。诊断单支、二支和三支冠状动脉病变患者的敏感性分别为5 0 %、73%、90 %。腺苷负荷试验心肌灌注显像判断血管病变的敏感性 77%、特异性 96 %、准确性 92 %。结论　腺苷负荷心肌灌注显像诊断冠心病敏感性及特异性均较高 ,具有重要的临床应用价值。     

Accuracy of thin-slice computed tomography in the detection of coronary stenoses.

AIM: Our aim was to investigate the accuracy of multislice spiral computed tomography (MSCT) in the detection of significant (>50%) coronary stenosis using a scanner equipped for 16 x 0.625 mm collimation. METHODS: In 64 patients (59 male, mean age 58 +/- 5 years) with suspected coronary artery disease, MSCT (GE Light Speed-16, collimation: 16 x 0.625 mm) was performed 20 +/- 5 days before coronary angiography (CAG). Only angiographic segments >1.5 mm were considered for analysis. RESULTS: In all patients, MSCT was carried out without complications. Three patients were excluded from the analysis. Of 729 angiographic segments, 613 (84%) were judged evaluable by MSCT. Considering only the segments judged evaluable, the sensitivity was 89%, specificity 98%, positive predictive value 90%, and negative predictive value 98%. Including all segments in the analysis (evaluable and nonevaluable), sensitivity was 78%. CONCLUSIONS: Using a scanner with a collimation of 16 x 0.625 mm, our study confirms the potential role of MSCT in the detection of significant coronary stenosis with a sensitivity of 89% and a very high specificity (98%). Exclusion criteria and less than full evaluability of the coronary arteries must still be considered limitations of the method.