小剂量多巴酚丁胺及其合用硝酸酯超声心动图试验识别冬眠心肌的对比研究

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Assessment of viable myocardium by dobutamine transesophageal echocardiography and comparison with fluorine-18 fluorodeoxyglucose positron emission tomography

Objectives. The aim of this study was to assess whether dobutamine transesophageal echocardiography can identify viable myocardium in patients with chronic myocardial infarction.Background. Experimental and clinical studies have shown that dobutamine can recruit a contraction reserve in postischemic viable but akinetic segments, indicating that dobutamine-induced functional recovery is a potential ultrasound marker of myocardial viability.Methods. Forty patients underwent rest and dobutamine transesophageal echocardiography (dobutamine 5, 10 and 20 μg/kg body weight per min) and fluorine-18 (F-18) fluorodeoxyglucose positron emission tomography at rest. Three representative shortaxis tomograms and a transverse four-chamber-view were used for wall motion and F-18 fluorodeoxyglucose-uptake analysis in corresponding myocardial regions. A basally asynergic segment was considered viable by transesophageal echocardiography if dobutamine-induced systolic wall motion could be observed. Viability by positron emission tomography was defined as F-18 fluorodeoxyglucose uptake ≥50% of the maximal uptake in a region with normal wall motion by left ventriculography.Results. Functional recovery within the infarct region was found in 21 (53%) of 40 patients during dobutamine infusion. Infarct region-related viability by F-18 fluorodeoxyglucose uptake was diagnosed in 25 (63%) of 40 patients, yielding a diagnostic agreement between both techniques in 90% of patients. In 210 (89%) of 235 akinetic segments at rest, data on myocardial viability were concordant by the two techniques. The positive and negative predictive accuracy of dobutamine transesophageal echocardiography for viability defined by F-18 fluorodeoxyglucose uptake was 81% and 97%, respectively. Such uptake was significantly different (p < 0.001) between segments remaining akinetic (mean ± SD 45 ± 9%) during dobutamine infusion and segments with a dobutamine-induced contraction reserve (68 ± 11%).Conclusions. Dobutamine transesophageal echocardiography provides a promising low cost and widely available approach to unmask myocardial viability in patients with chronic myocardial infarction, and results compare favorably with those of F-18 fluorodeoxyglucose positron emission tomography.     

Comparison of dobutamine echocardiography and positron emission tomography in patients with chronic ischemic left ventricular dysfunction

Objectives. The aim of this study was to correlate dobutamine-induced contractile reserve as detected by echocardiography with findings on positron emission tomography in patients with chronic ischemic left ventricular dysfunction.

Background. Contractile reserve induced by low dose dobutamine infusion has been proposed as a marker of myocardial viability.

Methods. Sixty patients with stable coronary artery disease and left ventricular dysfunction (mean ejection fraction [± SD] 29 ± 10%) underwent transthoracic echocardiography with dobutamine infusion (up to 10 μg/kg body weight per min) and positron emission tomography with nitrogen-13 ammonia and fluorine-18 (F-18) fluorodeoxyglucose as a perfusion and a metabolic tracer, respectively. Regional wall motion, perfusion and metabolism were analyzed semiquantitatively by using a 16-segment model. Segments with F-18 fluorodeoxyglucose uptake > 50% were considered viable on positron emission tomography.

Results. After dobutamine infusion, hemodynamic variables changed significantly, and myocardial ischemia was evident in 17 patients. All 60 patients had dysfunctional myocardium considered viable on positron emission tomography (8 ± 4 segments/patient), whereas 52 patients had dysfunctional myocardium with contractile enhancement by dobutamine echocardiography (4 ± 2 segments/patient, P = 0.01). The extent of dysfunctional myocardium with contractile reserve appeared to correlate less closely with the total extent of viable dysfunctional myocardium identified by positron emission tomography than with the number of such segments associated with a pattern of perfusion-metabolism mismatch.

Conclusions. In patients with chronic ischemic left ventricular dysfunction, echocardiography can be used to identify enhancement in the contractile function of viable dysfunctional myocardium after infusion of low dose dobutamine. In this study, the presence and extent of such enhancement were relatively less than the values obtained from positron emission tomography.     

Predictive value of M-mode echocardiography in patients with congestive heart failure

The M-mode echocardiogram (ECHO) is widely used to follow patients with congestive heart failure (CHF), but the value of ECHO for this purpose is unclear. In 49 patients with symptomatic CHF, we obtained ECHO during baseline evaluation to determine the value of ECHO for predicting 1-year survival or maximal oxygen uptake during exercise (VOmax). The cause of CHF was coronary artery disease in 12 patients and idiopathic dilated cardiomyopathy in 37 patients. Overall mortality at 1 year was 10 of 49 (20%), but was higher in patients with coronary artery disease (42%) compared to those with idiopathic dilated cardiomyopathy (14%), p less than 0.001. ECHO indices of left ventricular contractility were greater in survivors (S) in whom shortening fraction averaged 16 +/- 8 (SD)% vs 10 +/- 4% in nonsurvivors (NOS), p less than 0.025. Velocity of circumferential fiber shortening averaged 0.53 +/- 0.25 Hz in S vs 0.35 +/- 0.15 Hz in NOS, p less than 0.05. No left ventricular dimensions, including systolic and diastolic diameters, volume, wall thickness, and mass differed significantly between S and NOS. No ECHO measure of left ventricular dimensions or contractility correlated significantly with VOmax. Thus, ECHO may be useful to predict survival but not functional capacity in patients with CHF.     

Identification of viable myocardium by echocardiography during dobutamine infusion in patients with myocardial infarction after thrombolytic therapy: comparison with positron emission tomography

To assess the presence of viable myocardium salvaged by coronary artery reperfusion, 17 patients with acute anterior myocardial infarction were studied. Each received intravenous thrombolysis within the first 3 h of symptoms and underwent two-dimensional echocardiography before and during dobutamine infusion (10 micrograms/kg per min) 7 +/- 4 days after admission and positron emission tomography 9 +/- 5 days after admission. Echocardiography and positron emission tomography were again performed 9 +/- 7 months later. Six comparable segments specific for the territory of the left anterior descending artery were selected for comparison of the two techniques. Wall thickening was evaluated by using an echocardiographic score index. Segmental perfusion and glucose uptake were measured and normalized to the peak activity. A ratio of glucose uptake to perfusion was calculated for each segment. Concordant interpretation of the two techniques was found in 79% of affected segments for both acute and follow-up studies. Positron emission tomography revealed the presence of viable myocardium in 11 patients (group 1); perfusion was within normal limits in 5 of these (group 1A). Myocardial thickening improved with dobutamine infusion in these five patients, the echocardiographic score index decreasing from 12 +/- 2 at rest to 7.8 +/- 1.3 during dobutamine infusion (p = 0.003). Functional recovery was demonstrated in all five patients (follow-up score index 7.4 +/- 1.7). Six patients exhibited decreased perfusion but an abnormally high glucose to perfusion ratio (group 1B); their score index improved with dobutamine from 14.8 +/- 2.2 to 12 +/- 2.1 (p = 0.05), but late functional recovery was found in only one of the six patients (mean follow-up score index in group 1B 16 +/- 1.7). In the six remaining patients in whom no viable myocardium was detected with positron emission tomography (group 2), the echocardiographic score index did not change with dobutamine (15 +/- 0.9 to 14.7 +/- 0.8, p = NS) and there was no functional recovery (follow-up score index 15.5 +/- 1.0). Echocardiography during dobutamine infusion is a promising method to unmask viable myocardium in acute myocardial infarction. Early recovery of perfusion in the area at risk is associated with a good functional outcome, whereas a high glucose to perfusion ratio indicates jeopardized myocardium that frequently loses viability.     

Prognostic value of treadmill exercise and dobutamine stress positron emission tomography

BACKGROUND:

Although positron emission tomography (PET) is routinely performed using vasodilator stress, exercise and dobutamine stress are available alternatives. Evidence suggests that vasodilator PET myocardial perfusion imaging (MPI) has prognostic value, but the prognostic value of treadmill exercise and dobutamine PET MPI is unknown.

OBJECTIVE:

To determine the potential prognostic value of nonvasodilator stress PET MPI.

METHODS:

Patients underwent treadmill exercise or dobutamine PET MPI. Images were assessed qualitatively and semiquantitatively. PET results were categorized as normal (summed stress score [SSS] of less than 4), abnormal (SSS of 4 or greater) or inconclusive (SSS of less than 4 and submaximal peak stress heart rate). Patient follow-up (cardiac death, nonfatal myocardial infarction [MI] and/or late revascularization) was performed.

RESULTS:

Of the 124 patients (mean follow-up period of 2.3±1.6 years), 46 patients (37%) had a normal study, 15 patients (12%) had an inconclusive study and 63 (51%) had an abnormal PET. Patients with a normal PET had no deaths or nonfatal MI. One patient with a normal PET underwent late revascularization (annual event rate of 1.7%). Patients with an abnormal PET had 15 cardiac events (one cardiac death, four nonfatal MIs and 10 late revascularizations), with an annual event rate of 13.0% (P=0.002).

CONCLUSIONS:

Although small, the present study suggests that defects seen on PET myocardial perfusion, resulting from stressors (treadmill exercise and dobutamine) that increase myocardial oxygen demand, may have prognostic value.     

Predictive value of low dose dobutamine transesophageal echocardiography and fluorine-18 fluorodeoxyglucose positron emission tomography for recovery of regional left ventricular function after successful revascularization

Objectives. This study was designed to assess the predictive value of myocardial viability diagnosed by dobutamine transesophageal echocardiography and fluorine (F)-18 fluorodeoxyglucose positron emission tomography for left ventricular functional recovery after revascularization in patients with chronic left ventricular dysfunction.Background. The identification of akinetic but viable myocardium is of particular importance for the selection of patients with a compromised left ventricle who will benefit from coronary revascularization.Methods. Multiplane rest and dobutamine transesophageal echocardiography (dobutamine, 5 and 10 μg/min per kg) studies and F-18 fluorodeoxyglucose positron emission tomographic studies at rest were performed in 42 patients with 1) previous myocardial infarction and regional akinesia, 2) a stenosed infarct-related coronary artery, and 3) a patent infarct-related vessel after revascularization. A basally akinetic segment was considered viable by transesophageal echocardiography if dobutamine-induced contractile reserve could be observed. Viability by positron emission tomography was defined as F-18 fluorodeoxyglucose uptake ≥50% of the maximal uptake in a region with normal wall motion. Recovery of regional left ventricular function 4 t0 6 months after revascularization was diagnosed by transesophageal echocardiography if ≥50% of segments akinetic at baseline had improved wall thickening.Results. Dobutamine transesophageal echocardiography identified viable infarct regions in 25 (59%) of 42 patients, and F-18 fluorodeoxyglucose positron emission tomography in 30 (71%) of 42 patients, yielding diagnostic agreement in 86% of patients. Sensitivity and specificity for prediction of left ventricular functional recovery in individual patients was 92% and 88%, respectively, for dobutamine transesophageal echocardiography versus 96% and 69% for F-18 fluorodeoxyglucose positron emission tomography. Segments remaining akinetic after revascularization had a significantly lower (p < 0.001) F-18 fluorodeoxyglucose uptake (48 ± 15%) than that (73 ± 15%) of segments with recovery of regional left ventricular function.Conclusions. Both dobutamine transesophageal echocardiography and F-18 fluorodeoxyglucose positron emission tomography were highly sensitive in predicting functional recovery of chronically kinetic or dyskinetic myocardium after successful revascularization. Thus, dobutamine transesophageal echocardiography is a clinically valuable alternative to F-18 fluorodeoxyglucose positron emission tomography for assessing residual viability and predicting functional recovery after revascularization.     

Identification of ischemic and hibernating myocardium: feasibility of post-exercise F-18 deoxyglucose positron emission tomography

The identification of ischemic and hibernating myocardium facilitates the selection of patients most likely to benefit from revascularization. This study examined the feasibility of metabolic imaging, using post-exercise F-18 deoxyglucose positron emission tomography (FDG-PET) for the diagnosis of both ischemia and hibernation in 27 patients with known coronary anatomy. Normal post-exercise FDG uptake was defined in each patient by reference to normal resting perfusion and normal coronary supply. Abnormal elevation of FDG (ischemia or hibernation) was compared in 13 myocardial segments in each patient, with the results of dipyridamole stress perfusion imaging performed by rubidium-82 positron emission tomography (Rb-PET). Myocardial ischemia was diagnosed by either FDG-PET or Rb-PET in 34 segments subtended by significant local coronary stenoses. Increased FDG uptake was present in 32/34 (94%) and a reversible perfusion defect was identified by Rb-PET in 22/34 (65%, p less than .01). In 3 patients, ischemia was identified by metabolic imaging alone. In 16 patients with previous myocardial infarction, perfusion defects were present at rest in 89 regions, 30 of which (34%) demonstrated increased FDG uptake, consistent with the presence of hibernation. Increased post-exercise FDG uptake appears to be a sensitive indicator of ischemia and myocardial hibernation. This test may be useful in selecting post-infarction patients for revascularization.     

Predictive value of early 18F-fluoro-deoxyglucose positron emission tomography in chemosensitive relapsed lymphoma

18F-fluoro-deoxyglucose (FDG) positron emission tomography (PET) might be a better tool than computerized tomography (CT) in predicting long-term treatment outcome in patients with relapsed chemosensitive lymphoma who are candidates for autologous stem cell transplantation (ASCT). We studied patients with recurrent or persistent aggressive non-Hodgkin's lymphoma (NHL) and Hodgkin's disease (HD), who were treated with three courses of second-line induction chemotherapy [DHAP-VIM (dexamethasone, cytarabine, cisplatin followed by etoposide, iphosphamide and methotrexate)-DHAP], followed by myeloablative therapy and ASCT if chemosensitive. FDG-PET was performed in parallel to conventional diagnostic methods before starting, and after two courses of, second-line therapy. Of 68 relapsed lymphoma patients, 46 chemosensitive patients (33 NHL and 13 HD) were included, of whom 39 were transplanted. After DHAP-VIM, the second PET scan was normalized in 15/46 patients; progression-free survival at 2 years was 62% for PET-negative patients versus 32% for PET-positive patients (P = 0.048). The relative risk for progressive disease in patients with < 90% intensity reduction was 2.85 (95% confidence interval 1.15-7.05, P = 0.018). Early FDG-PET may help to predict the long-term treatment outcome of ASCT in chemosensitive patients with relapsed lymphoma and identify those patients who need extra or alternative treatment. Disappearance or > 90% reduction of intensity of abnormal FDG uptake after two courses of reinduction therapy was correlated with a favourable outcome.     

Comparison of real-time myocardial contrast echocardiography for the assessment of myocardial viability with fluorodeoxyglucose-18 positron emission tomography and dobutamine stress echocardiography

Little is known about the diagnostic value of real-time myocardial contrast echocardiography (MCE) for the assessment of myocardial viability. We compared the diagnostic accuracy of MCE with that of low-dose dobutamine stress echocardiography (DSE) and of combined technetium-99 sestamibi single-photon emission computed tomography and fluorodeoxyglucose-18 positron emission tomography and investigated whether quantitative assessment of myocardial blood flow could increase its diagnostic value. Cardiac imaging was performed with these 3 methods in 41 patients who had ischemic heart disease (ejection fraction < 40%) and were being considered for revascularization. Follow-up echocardiograms were obtained after 3 to 6 months in revascularized patients, and increased regional function served as a standard reference for assessment of myocardial viability. A control group of 25 patients who had no coronary artery disease underwent MCE to assess normal values of myocardial perfusion parameters. Recovery of myocardial function was predicted by MCE with a sensitivity of 86% and a specificity of 43%. Nuclear imaging was comparably sensitive (90%) and specific (44%), whereas low-dose DSE was similarly sensitive (83%) but more specific (76%). Normalization of myocardial signal intensity to that of the control group significantly increased the specificity of MCE from 43% to 64% and the accuracy from 73% to 81%. A combination of quantitative MCE and DSE provided the best diagnostic characteristics, with a sensitivity of 96%, a specificity of 63%, and an accuracy of 83%. Thus, MCE is useful for assessing myocardial viability. Normalization of contrast intensity to that of a reference control group is a valid approach for detection of myocardial viability and expands on information obtained from visual MCE and DSE.     

Prediction of functional recovery in patients with myocardial infarction after revascularization--comparison of low-dose dobutamine stress echocardiography with fluorine-18 fluorodeoxyglucose positron emission tomography

The present study investigated the agreement between low-dose dobutamine stress echocardiography (LDDSE) and fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET) and compared each technique's ability to detect myocardial viability and predict functional recovery in 30 patients. All patients underwent revascularization, followed by echocardiography 5+/-3 months. Of the 390 segments analyzed by echocardiography before revascularization, 110 (28%) had abnormal wall motion. LDDSE showed viability in 66 sites of the 110 dyssynergic segments and 58 of these viable segments recovered their wall motion. With FDG-PET, 78 of the 110 dyssynergic segments were diagnosed as viable and 62 of these showed improvement of the wall motion. The sensitivities for LDDSE and FDG-PET to assess functional recovery were 84% and 90%, respectively; specificities were 80% and 64%, respectively. Positive predictive values for LDDSE and FDG-PET were 88% and 79%; negative predictive values were 75% and 78%, respectively. Both methods had good sensitivity for detecting improvement in regional function after revascularization, but LDDSE had a higher specificity for detecting viability and a better positive predictive value for left ventricular functional recovery.     

小剂量多巴酚丁胺合用硝酸酯超声心动图识别冬眠心肌

目的评价小剂量多巴酚丁胺（Ｄｏｂｕ）合用硝酸异山梨酯（异舒吉）二维超声心动图（２ＤＥ）试验识别冬眠心肌的准确性和安全性。方法陈旧性心肌梗塞患者２３例，行小剂量Ｄｏｂｕ（３～５μｇ·ｋｇ－１·ｍｉｎ－１）合用异舒吉（２４０～３００μｇ／ｍｉｎ）２ＤＥ试验，并成功进行了冠状动脉血运重建术（ＣＲＶ），术后３个月左右完成２ＤＥ随访。用１６节段半定量法分析各节段收缩运动和增厚情况并予分级和计分。将该试验检出的冬眠心肌节段与ＣＲＶ术后其收缩功能改善的实际对比，计算出识别冬眠心肌的准确性，并评价其安全性。结果在１２２个异常节段中，小剂量Ｄｏｂｕ合用异舒吉２ＤＥ检出了６７２％～６８０％的冬眠心肌节段，与ＣＲＶ术后对比识别冬眠心肌的敏感性，特异性和准确性分别为８４６％～８５７％，８３．９％和８４４％～８５３％。副作用轻。结论小剂量Ｄｏｂｕ合用异舒吉２ＤＥ试验是识别冬眠心肌的准确方法，且由于异舒吉抗心肌缺血及Ｄｏｂｕ用量小而更安全     

Predictive value of admission electrocardiography in patients with heart failure

Admission electrocardiography (ECG) in heart failure (HF) patients provides important diagnostic information; however, there are limited data regarding the prognostic significance of ECG parameters for predicting cardiac events (CEs). The ECGs of 246 patients admitted with acute HF were evaluated for heart rate, rhythm, QRS and ST-T wave abnormalities, QTc duration, QT peak corrected (QTpc), T amplitude, and axis. The end points included rehospitalization for a CE or death during 30-day follow-up. There were 71 (29%) patients with CEs. In patients with CEs, atrial fibrillation (AF) was observed more frequently (27% vs 13%, respectively; P=.009) and QTpc was shorter (370+/-43 vs 386+/-44 ms, respectively; P=.020). Multivariate logistic regression analysis revealed that QTpc 相似文献   

硝酸酯、小剂量多巴酚丁胺及其合用超声心动图试验识别急性心肌梗死存活心肌的对比研究

目的对比硝酸酯、小剂量多巴酚丁胺(Dob)及其合用二维超声心动图(2DE)试验识别急性心肌梗死(AMI)存活心肌的准确性和安全性。方法AMI患者31例,于发病后7～14(10±3)d行硝酸酯、小剂量Dob及其合用2DE试验,后行冠状动脉血运重建(CRV)术成功,术后6个月左右(167±18)d复查2DE。用16节段半定量分析法对左室各节段收缩运动和增厚情况给予分级记分。将2DE试验所检的存活心肌与CRV术后其收缩功能改善的实际对比,评价识别AMI存活心肌的准确性和安全性。结果31例AMI患者共有221个异常节段。与硝酸酯和Dob3μg单用时相比,两者合用2DE试验对AMI区存活心肌节段的检出率均显著提高（50.2%对37.6%和40.7%,P均<0.05）,识别敏感性和准确性也均显著提高（77.6%对56.8%和61.6%,81.0%对70.1%和72.4%,P<0.05～0.01）;而硝酸酯合用Dob5μg2DE试验对存活心肌的检出率、识别敏感性和准确性均已达Dob10μg单用时的水平（55.7%对55.8%,87.2%对89.5%和86.4%对87.9%,P均>0.05）,而又无Dob10μg诱发心肌缺血的副作用。结论硝酸酯与小剂量(3、5μg     

Prediction of functional recovery of hibernating myocardium using harmonic power Doppler imaging and dobutamine stress echocardiography in patients with coronary artery disease

The aim of this study was to compare the accuracy of harmonic power Doppler imaging (HPDI) and dobutamine stress echocardiography (DSE) in predicting recovery of myocardial function after bypass surgery. HPDI using triggering imaging with the administration of Levovist (Shering AG, Berlin, Germany) and DSE were performed in 34 patients (mean age 64 ± 5 years) with left ventricular dysfunction. A repeat echocardiogram at rest was performed 3 months after revascularization. Of the 408 revascularized dysfunctional segments, 188 (45%) improved on the repeat echocardiogram. HPDI exhibited overall similar sensitivity (88% vs 87%) and accuracy (74% vs 79%) but lower specificity (61% vs 72%, p<0.05) compared with DSE for predicting recovery of myocardial function. Only delayed opacification at the 1:8 triggering point, demonstrated in 62% of viable segments, exhibited higher sensitivity (63%) and positive (58%) and negative (66%) predictive values than early opacification at 1:4 (25%, p<0.001; 35%, p<0.001; and 49%, p<0.001, respectively) in predicting functional recovery. The presence of contrast enhancement within the revascularized area resulted in a significant improvement after revascularization in wall motion score index and ejection fraction compared with areas with residual contrast defect (1.9 ± 0.3 vs 2.3 ± 0.3, p<0.01; 36 ± 6% vs 29 ± 5%, p<0.01, respectively). Significant correlations were observed between the contrast score index and the follow-up wall motion score index (r = −0.67) and between the contrast score index and the follow-up ejection fraction change (r = 0.65). Triggered HPDI has high sensitivity in detecting hibernating myocardium and can accurately predict the potential for recovery of ischemic left ventricular dysfunction 3 months after revascularization.     

Assessment of myocardial viability by dobutamine echocardiography,positron emission tomography and thallium-201 SPECT: Correlation with histopathology in explanted hearts

Objectives. We examined the relationship among viability assessment by dobutamine echocardiography (DE), positron emission tomography (PET) and thallium-201 single-photon emission computed tomography (Tl-SPECT) to the degree of fibrosis.Background. DE, PET and Tl-SPECT have been shown to be sensitive in identifying viability of asynergic myocardium. However, PET and Tl-SPECT indicated viability in a significant percentage of segments without dobutamine response or functional improvement after revascularization.Methods. Twelve patients with coronary artery disease and severely reduced left ventricular function (EF 14.5 ± 5.2%) were studied with DE prior to cardiac transplantation: 5 had additional PET and 7 had Tl-SPECT studies. Results of the three techniques were compared to histologic findings of the explanted hearts.Results. Segments with >75% viable myocytes by histology were determined to be viable in 78%, 89% and 87% by DE, PET and Tl-SPECT; those with 50–75% viable myocytes in 71%, 50% and 87%, respectively. Segments with 25–50% viable myocytes showed response to dobutamine in only 15%, but were viable in 60% by PET and 82% by Tl-SPECT. Segments with <25% viable myocytes responded to dobutamine in 19%; however, PET and Tl-SPECT demonstrated viability in 33% and 38%, respectively. Discrepant segments without dobutamine response but viability by PET and SPECT had significantly more viable myocytes by pathology than did those classified in agreement to be nonviable but had significantly less viable myocytes than those classified in agreement to be viable (p < .001).Conclusions. These findings suggest that contractile reserve as evidenced by a positive dobutamine response requires at least 50% viable myocytes in a given segment whereas scintigraphic methods also identify segments with less viable myocytes. Thus, the methods may provide complementary information: Nuclear techniques appear to be highly sensitive for the detection of myocardial viability, and negative tests make it highly unlikely that a significant number of viable myocytes are present in a given segment. Conversely, dobutamine echo may be particularly useful for predicting recovery of systolic function after revascularization.     

N末端B型利钠肽原对单纯主动脉瓣狭窄心力衰竭患者的诊断价值

目的 评价N末端B型利钠肽原(NT-proBNP)对单纯主动脉瓣狭窄(AS)心力衰竭(心衰)患者的诊断价值.方法 使用酶联免疫的方法对40例AS心衰患者(AS心衰组)和76例正常对照者(正常组)行NT-pmBNP测定,评价其对AS心衰的诊断价值.结果 与正常组相比,AS心衰组NT-proBNP水平显著增高(P<0.01)且在纽约心功能分级(NYHA分级)Ⅱ、Ⅲ和Ⅳ级者呈逐级显著升高(均为P<0.01);其中,临床代偿心衰差异无统计学意义(P>0.05),而临床失代偿心衰升高8倍(P<0.01);在左室舒张期末内径(LVEDD)>50 mm组显著高于LVEDD≤50mm组(P<0.05),左室射血分数(LVEF)≤60%组显著高于LVEF>60%组(P<0.01);在合并心房颤动组显著高于窦性心律组(P<0.05).NT-pmBNP阈值在1360 ng/L时,是诊断心衰(ROC曲线下面积=0.762,P<0.01)及失代偿心衰(ROC曲线下面积=0.997,P<0.01)的最佳阈值;心衰与失代偿心衰诊断的敏感性分别为67.50%和100.00%,特异性均为96.05%,准确性分别为86.21%和95.83%.单因素和多元逐步回归分析一致显示,Log(NT-proBNP)与NYHA分级和LVEF呈显著正、负相关(P<0.05),且呈独立相关.结论 NT-pwBNP对单纯As心衰患者也有重要诊断价值.建议临床采用1360 ng/L作为阈值,诊断单纯AS伴心衰者准确性高达86.21%,尤其对失代偿者准确性高达95.83%.