The Acute Administration of Trimetazidine Modified Myocardial Perfusion and Left Ventricular Function in 31 Patients with Ischaemic Ventricular Dysfunction

Trimetazidine (TMZ) increases the mithocondrial oxidative metabolism and improves Tc-99m sestamibi uptake in myocardial single photon emission tomography (SPECT). The aim of this study was to evaluate whether the acute administration of TMZ improved myocardial perfusion and modified left ventricular ejection fraction (LVEF) in ischaemic left ventricular impairment. METHODS: Thirty-one patients (23 males, age 66 years) with prior myocardial infarction (>6 months) and echocardiographic LVEF < or = 45% underwent coronary angiography, rest basal myocardial SPECT (after 3-day placebo administration) and rest TMZ myocardial SPECT [after 3-day TMZ administration (60mg/die)]. The left ventricle was analysed in 16 segments. The summed placebo score (SPS) and the summed TMZ score (STS) were calculated with a 5-point scale (from 0 = normal uptake to 4 = absent uptake) by two blinded operators. The GATED Tc-99m SPECT was always provided. RESULTS: After TMZ administration GATED LVEF improved from 26.5+/-9.7% to 29.1+/-11.3% (p = 0.04) and left ventricular end-systolic volume (LVESV) was reduced from 90.2+/-40.7 to 85.6+/-39.2 ml/mq (p = 0.006). Similarly the addition of TMZ to myocardial SPECT significantly reduced the STS compared to SPS (21.5+/-11 vs. 26.6+/-10.5 p = 0.0001). Eleven patients (35.5%) had an echocardiographic LVEF < or = 30%; in these patients who had severe ventricular dysfunction, GATED LVEF and LVESV did not change after TMZ (20.2+/-5.7% vs. 21+/-6.9% p =0.6; 116.7+/-35.3 ml vs. 112.6+/-32.3 ml p = 0.08, respectively). CONCLUSION: In comparison with placebo, the addition of TMZ to myocardial Tc-99m tetrofosmin SPECT improved myocardial perfusion and LVEF, reducing LVESV. These effects were lost in patients with more severe ventricular dysfunction.     

Comparison of echocardiography using tissue harmonics and contrast harmonics with radionuclide angiography for the assessment of left ventricular function.

BACKGROUND: Left ventricular ejection fraction (LVEF) is a significant predictor of morbidity and mortality; however, the optimal noninvasive modality for the quantitative determination of LVEF is not apparent. HYPOTHESIS: We verified the hypothesis that the various echocardiographic methods of assessing LVEF using the Method of Discs with contrast (Optison human albumin microspheres; Amersham Health, Princeton, NJ) and visual assessment of LVEF using tissue harmonics and contrast harmonics compare favorably with radionuclide angiography (RNA). METHODS: In a prospective analysis, 24 consecutive patients scheduled to undergo RNA had an echocardiogram using tissue harmonics and contrast harmonics on the same day. LVEF was assessed by RNA by an experienced, blinded reader using manual determination of the region of interest. LVEF was calculated using the Method of Discs (Simpson's Rule) by a blinded sonographer. LVEF was visually estimated by two blinded readers using echocardiography with tissue harmonics and contrast harmonics on separate occasions. RESULTS: By linear regression analysis, LVEF determination by echocardiography with contrast using the Method of Discs correlated well with RNA (r = .835, p < .0005). Using Bland-Altman analysis, the second echocardiogram reader had excellent agreement with RNA, whereas the first reader had a mean difference of 5.25% (CI 1.3-9.2; p = .012) with visual assessment using tissue harmonics and a mean difference of 4.67% (CI 0.4-8.8; p = .031) with visual assessment using contrast harmonics compared with RNA. Thus, a small difference in agreement between RNA and echocardiographic visual estimation was noted that appeared to be primarily reader dependent. CONCLUSIONS: LVEF determination with echocardiography with contrast using the Method of Discs correlated well with RNA and provided agreement across a range of cardiac functions. Visual echocardiographic assessment of LVEF with both tissue harmonics and contrast harmonics correlated well with RNA, but contrast harmonics did not appear to offer an advantage over tissue harmonics alone.     

Left ventricular ejection fraction measurements: accuracy and prognostic implications in a large population of patients with known or suspected ischemic heart disease

We sought to compare the reliability and prognostic implications of left ventricular (LV) ejection fraction (EF) measurements obtained in routine clinical practice. We retrospectively selected from our clinical database a group of 422 patients with known or suspected ischemic heart disease, studied by two-dimensional echocardiography, gated single-photon emission computed tomography (SPECT) and left ventriculography (LVG) for clinical purposes. In each diagnostic procedure LVEF was measured as done routinely. The LVEF values obtained by the three methods were similar and closely related. The correlation coefficient r was equal to 0.83 between echocardiographic and LVG, to 0.75 between gated SPECT and LVG and to 0.81 between echocardiographic and SPECT. During follow-up (median 41 months), 31 patients died. The values of LVEF obtained by echocardiography, gated-SPECT and LVG were all powerful predictors of all-cause mortality: chi(2) = 12.3 for echocardiography, 14.4 for gated SPECT and 14.5 for LVG. However, including LVEF values into a model based on patient age, sex, history of angina, evidence of previous infarction and number of stenotic coronary arteries, the ability to predict patient survival significantly increased only including LVEF values measured by gated SPECT (chi(2) = 40.6, P = 0.039). Thus, in a large cohort of unselected patients with known or suspected ischemic heart disease, the values of LVEF routinely measured by echocardiography, gated SPECT and LVG were closely correlated, and provided a powerful prognostic information, that was incremental to clinical variables for gated SPECT.     

超声心动图和血管造影检测动脉导管未闭最小直径和类型的对比研究

目的 评价超声心动图检测动脉导管未闭（PDA）最小直径和类型的价值。方法 收集既有超声心动图又有血管造影测量PDA直径的患者262例,既有超声心动图又有血管造影PDA类型的患者55例,对比两种检查方法的结果。结果 超声心动图测量PDA最小直径显著高于血管造影（P＜0．01）。除5例漏斗型和6例管型PDA超声心动图与血管造影所见一致外,其余44例（80％）PDA类型超声心动图所见均与血管造影不一致。结论 选择经导管PDA封堵术适应证、封堵方法和封堵器型号目前应以血管造影为标准,超声心动图可起初步筛选作用。     

Comparison of radionuclide angiography with three echocardiographic parameters of left ventricular function in patients after myocardial infarction

Aims. Left ventricular function is an important outcome measure in patients with coronary artery disease, in particular in patients after myocardial infarction. It is reliably assessed by radionuclide angiography, but echocardiographic wall motion scoring might be an attractive alternative. Methods. Four days after reperfusion therapy for acute myocardial infarction both radionuclide angiography and echocardiography were performed in 90 patients. Segmental wall motion scoring (WMSI) and visual estimation of the left ventricular ejection fraction (LVEF) was done by 2 independent observers. Repeated analysis was performed 1 month after the first reading. In 41 patients the LVEF was assessed quantitatively by tracing of endocardial outlines of the left ventricle. Results. Both correlation with radionuclide angiography (estimated LVEF: r = 0.71, WMSI: r = ? 0.68, Tracing: r = 0.59) and inter- and intra-observer variability (estimated LVEF: 19% and 15%, WMSI: 65% and 59%) were in favour of the LVEF estimation method. Correlation with radionuclide angiography measurements was related to the quality of the echocardiogram and to the extent of coronary artery disease. Conclusion. Simple echocardiographic estimation of left ventricular ejection fraction in patients after reperfusion therapy for acute myocardial infarction proved to be superior to quantitative assessment of ejection fraction and to segmental wall motion scoring in comparison with radionuclide angiography.     

A visual approach for the accurate determination of echocardiographic left ventricular ejection fraction by medical students.

BACKGROUND: Previously published reports show that there is significant intraobserver, interobserver, and interinstitutional variability in the determination of left ventricular (LV) ejection fraction (EF) by echocardiography. With the increased deployment of echocardiography (eg, handheld devices), there exists a need for developing a simple, intuitive approach for evaluating LVEF that allows a wider range of physicians to accurately and rapidly determine LVEF. OBJECTIVE: We sought to create a system for assessing LVEF that relies on recognition and matching of patterns, rather than on mathematic calculations and geometric assumptions. METHODS: A library of videoclips of cardiac function was compiled from 54 patients who spanned the spectrum of LVEF. LVEFs were calculated for these patients using standard echocardiographic methods, with further validation of a subsample using cardiac magnetic resonance imaging measurement of LVEF. The library of images was used to create a software tool for assessing LVEF on the basis of a "template-matching" approach. The software tool was then tested on medical students (N=13) to determine whether it enabled relatively untrained individuals to make accurate LVEF estimates. RESULTS: Using a template-matching approach for interpretation of echocardiograms, medical students were able to accurately estimate LVEF after only a limited introduction to echocardiography. Their LVEF estimates showed good correlation and agreement with gold standard (r = 0.88, standard square of the estimate = 6.0, limits of agreement = +12.0%, -15.6%). CONCLUSIONS: A new visual approach for assessing cardiac function using template matching can accurately estimate LVEF. With minimal training, medical students can make LVEF estimates that correlate well with gold standard. The application of this new approach includes allowing for the interpretation of LVEF from echocardiograms to be performed by a broader spectrum of physicians.     

ECToolbox软件计算左心室射血分数的适用性

目的 评价ECToolbox软件中R0、R1、R2公式计算门控心肌灌注显像左心室射血分数(LVEF)的适用性.方法 64例患者[冠状动脉粥样硬化性心脏病(CHD)44例;高血压病20例]接受静息态门控心肌灌注显像(~(99m)Tc-MIBI)和平衡法门控心血池显像(~(99m)Tc-RBC),用ECToolbox软件中的R0、R1、R2公式分别计算LVEF,称为R0 LVEF、R1 LVEF、R2 LVEF.将三种公式的计算结果与平衡法门控心血池显像计算结果对比分析.结果 R0、R1、R2公式LVEF值与门控心血池显像LVEF值均有相关性(r=0.905、0.905、0.903,P均<0.05);χ~2检验三种公式LVEF值落入门控心血池显像LVEF值±15%准确率分别为54.30%、71.40%、22.90%,±30%的准确率为81.40%、88.60%、74.30%;Wilcoxon配对检验结果示R1公式计算结果与门控心血池显像计算结果差异无统计学意义,R0、R2公式计算结果与门控心血池显像计算结果差异有统计学意义.结论 门控心肌灌注显像用ECToolbox软件计算CHD和高血压患者的LVEF时,R1公式最为适用.     

Evaluation of left ventricular volumes and ejection fraction by automated gated myocardial SPECT versus cardiovascular magnetic resonance

BACKGROUND: Electrocardiogram-gated myocardial single-photon emission computed tomography (SPECT) with (99m)Tc-tetrofosmin allows simultaneous evaluation of myocardial perfusion and function. In this study, left ventricular volumes, ejection fraction (LVEF), and left ventricular wall volume (LVWV) derived from gated SPECT were compared with measurements from cardiovascular magnetic resonance (CMR), performed within a few hours. METHODS: The study population included 55 patients with known or suspected coronary artery disease, including 13 patients with recent acute myocardial infarction. End-diastolic (EDV) and end-systolic (ESV) volumes, LVEF and LVWV were derived automatically from gated SPECT using commercially available software (QGS). In the CMR studies, manually delineated endocardial and epicardial borders on short-axis slices were used to calculate the volumes. RESULTS: Gated SPECT underestimated EDV by 35 +/- 14 ml (mean +/- SD) (P < 0.001), ESV by 10 +/- 13 ml (P < 0.001), and LVEF by 4 +/- 7 percentage points (P < 0.001). There were no systematic difference in EDV, ESV or LVEF between the methods. SPECT underestimated LVWV by 49 +/- 30 ml (P < 0.001), with a trend towards increasing underestimation by SPECT for larger wall volumes. CONCLUSION: These findings show that gated SPECT slightly underestimates EDV, ESV and LVEF compared with CMR. This underestimation is systematic, however, indicating that ventricular volumes derived from gated SPECT are robust enough to guide clinical management. Estimates of LVWV in patients with large wall volumes are less accurate.     

Assessment of left ventricular function: comparison of cardiac multidetector-row computed tomography with two-dimension standard echocardiography for assessment of left ventricular function

OBJECTIVE: To compare global Left Ventricular (LV) systolic function assessment by 16-detector row Computed Tomography (MDCT) with Two-Dimensional Standard Echocardiography (2DSE) in a routine cardiology practice setting and to ascertain the degree of correlation between LV volumes and measurements obtained by 2DSE with those measured by MDCT. METHODS: In 52 patients with suspected coronary artery disease, a contrast enhanced MDCT study was performed using retrospective gating without dose modulation for better endocardial delineation. Eight phases of the cardiac cycle were analyzed to identify the end-diastolic and end-systolic phases. 2DSE was performed on the same day. Left ventricular systolic and diastolic volumes and ejection fraction were calculated in 4-chamber, 2-chamber and biplane (average of the two) views. Endocardial tracing was used to measure ventricular volumes by area length method for CT and Simpson's method for echocardiography. RESULTS: On MDCT, mean LV ejection fraction (LVEF) in 4-chamber, 2-chamber and biplane views were 58.4 +/- 12, 59.3 +/- 12 and 59.7 +/- 12% respectively. On 2DSE, mean LVEF in 4-chamber, 2-chamber and biplane views were 58 +/- 14, 57 +/- 16 and 58 +/- 13% respectively. LVEF correlated best using the biplane views (r = 0.59 and P < 0.01) compared to 2-chamber (r = 0.57 and P < 0.01) and 4-chamber views (r = 0.32 and P = 0.02). Biplane measurement by these two techniques correlated well for LV volumes in both diastole (r = 0.69 and P < 0.01) and systole (r = 0.73 and P < 0.01), although MDCT consistently gave higher values. CONCLUSIONS: MDCT can be a useful tool to measure LVEF while patients are undergoing CT coronary angiography.     

Comparison of myocardial gated single photon emission computerised tomography, planar radionuclide ventriculography and echocardiography in evaluating left ventricular ejection fraction, wall thickening and wall motion

Left ventricular ejection fraction (LVEF) and wall thickening are fundamental aspects of cardiac function. Recently, gated single photon emission computerised tomography (GSPECT) and anatomical M-mode echocardiography are new techniques, which have been introduced for the evaluation of left ventricular wall thickening and ejection fraction. These, however, have not been evaluated against established techniques, including equilibrium radionuclide ventriculography (ERNV), which remains the current gold standard for the evaluation of LVEF. We examined the concordance between LVEF, wall motion and wall thickening scores derived from GSPECT, echocardiography and ERNV, in a group of 16 patients with suspected ischaemic heart disease. Estimated ejection fraction correlated better between ERNV and gated SPECT (R2 = 0.93) than between echocardiography and either gated SPECT (R2 = 0.62) or ERNV (R2 = 0.71). There was poor correlation between gated SPECT and anatomical M-mode echocardiography in the assessment of wall thickening (83/150, 56%; kappa= 0.31, p < 0.05) and similar correlation (100/150, 66%; kappa = 0.29, p < 0.01) for wall motion analysis. In conclusion, estimations of ejection fraction by all the three studied modalities agreed to a degree sufficient for routine clinical practice. However, estimates of wall thickening from echocardiography cannot be used interchangeably with those derived from gated myocardial perfusion SPECT.     

Myocardial systolic synchrony measured by Doppler tissue imaging as a role of predictor of left ventricular ejection fraction improvement in severe congestive heart failure

BACKGROUND: The recovery of left ventricular ejection fraction (LVEF) appears to be prognostic of survival in congestive heart failure (CHF). The aim of our study was to evaluate which parameters appear to predict LVEF improvement in CHF. METHODS: In all, 85 patients (age 64 +/- 12 years) with CHF and LVEF <35% were enrolled. Doppler tissue imaging was performed on 5 basal and 5 midsegments to assess the time from R wave to peak systolic velocity (Ts). The standard deviation (SD) of Ts was an indicator of systolics synchrony. After at least 3 months of intensive medical therapy with beta-blocker and angiotensin-converting enzyme inhibitors, follow-up echocardiography was performed. By the change in LVEF, we divided patients into group I (<5%, n = 47) and group II (>/=5%, n = 38). RESULTS: Baseline clinical and echocardiographic parameters were similar in both groups. There was negative correlation between SD of Ts and change of LVEF ( r = -0.43, P < .001). The multivariate analysis shows that SD of Ts and dose of beta-blocker were independent predictors of LVEF improvement. CONCLUSION: Myocardial systolic synchrony measured by Doppler tissue imaging is a predictor for LVEF improvement in severe CHF independently from QRS duration, cause of CHF, baseline LVEF, and chamber dimension.     

Does a Gender Difference in Response to Cardiac Resynchronization Therapy Exist?

BACKGROUND: Cardiac resynchronization therapy (CRT) has a beneficial effect on clinical symptoms, exercise capacity, and systolic left ventricular (LV) performance in patients with heart failure. The aim of the current study was to evaluate whether a gender difference exists in response to CRT. METHODS: Consecutive patients with end-stage heart failure (New York Heart Association, NYHA, class III-IV), LV ejection fraction (LVEF) < or =35%, QRS duration >120 ms, and left bundle branch block configuration underwent CRT. At baseline and 6 months post-CRT, clinical and echocardiographic parameters were evaluated; follow-up was obtained up to 5 years. The effects of CRT were compared between women and men. RESULTS: The study population comprised 137 men and 36 women (mean age 66 +/- 11 years). No differences in baseline characteristics were observed except that nonischemic cardiomyopathy was more frequent in women than men (67% vs 38%, P < 0.05). In all patients, clinical and echocardiographic parameters improved significantly at 6-month follow-up. The magnitude of improvement in different parameters was similar between women and men, e.g., the improvement in NYHA Class was 0.9 +/- 0.6 in women and 1.0 +/- 0.7 in men (NS) and the increase in LVEF was 8 +/- 8% in women as compared to 7 +/- 9% in men (NS). The percentage of individual responders was not different between women and men (76% vs 80%, NS) and 2-year survival was comparable for women and men (84% vs 80%, NS). CONCLUSION: No gender differences were observed in response to CRT and long-term survival after CRT.     

Evaluation of myocardial glucose metabolism before and after recovery of myocardial function in patients with tachycardia-induced cardiomyopathy

BACKGROUND: We assessed left ventricular (LV) function and myocardial glucose metabolism by fluoro-18-deoxyglucose (18F-FDG) positron emission tomography (PET) in patients with tachycardia-induced cardiomyopathy (TC). METHODS: The subjects were 42 patients with heart disease, consisting of 7 patients with TC (61.4 +/- 19.0 years, LVEF 34.1%+/- 10.6%) and 35 with ischemic heart disease (IHD) (63.1 +/- 10.8 years, LVEF 49.9%+/- 13.5%). Five volunteers with normal ECG were the control group. All of the patients underwent 18F-FDG PET and echocardiography, and all of the patients with TC underwent 18F-FDG PET and echocardiography before and 6 months after antitachycardia therapy. Six patients underwent radiofrequency catheter ablation (RFCA) and 1 patient was medically treated with antitachycardia therapy. Myocardial glucose metabolism was assessed semiquantitatively by using the % dose uptake of 60 kg of BW (% dose uptake). RESULTS: Mean % dose uptake of the control group was 5.52 +/- 0.54%. After antitachycardia therapy, LVEF significantly improved (34.1 +/- 10.6% vs 54.3 +/- 13.6%, P < 0.01), and % dose uptake also significantly improved (1.26 +/- 0.55% vs 1.49 +/- 0.62%, P < 0.05). Patients with IHD showed higher % dose uptake than those with TC before antitachycardia therapy (3.18 +/- 1.36 vs 1.26 +/- 0.55%, P < 0.01), controls showed higher value of % dose uptake than TC before antitachycardia therapy (5.52 +/- 0.54% vs 1.26 +/- 0.55%, P < 0.01). CONCLUSION: Semiquantitative analysis of 18F-FDG PET showed that antitachycardia therapy improved myocardial glucose metabolism in patients with TC.     

Population-Based Study of the Use of Cardiac Stress Imaging and Referral for Coronary Angiography and Repeated Revascularization After Coronary Artery Bypass Graft Surgery

ObjectiveTo assess stress single-photon emission computed tomography (SPECT) and stress echocardiography use after coronary artery bypass grafting (CABG) and their effect on referral for coronary angiography and revascularization.Patients and MethodsThe referral, timing, and results of stress imaging after CABG; referral for coronary angiography and revascularization; and all-cause mortality were assessed in this longitudinal, population-based, retrospective study of 1138 Olmsted County, Minnesota, patients undergoing CABG between January 1, 1993, and December 31, 2003.ResultsA total of 570 patients (50.1%) underwent a stress imaging study (341 SPECT and 229 echocardiography) during the study period. Of the 1138 patients, 372 (32.7%) were referred for coronary angiography, and 144 of those patients (12.7%) underwent repeated revascularization (132 percutaneous revascularization and 12 CABG). The median interval between CABG and the index stress imaging study was 3.0 years (25th-75th percentile, 1.2-5.7 years). The results of 75.7% (258 of 341) of the stress SPECT studies and 70.7% (162 of 229) of the stress echocardiograms were abnormal. Seventy-six of 570 patients (13.3%) referred for stress imaging underwent coronary angiography within 180 days after the stress test. Repeated coronary revascularization was performed in 25 patients (4.4%) who underwent a stress imaging study within the preceding 180 days. The 5- and 10-year survival rates in the entire study cohort (83.5% and 65.1%, respectively) were not significantly different than predicted for the age- and sex-matched Minnesota population.ConclusionHalf of this community-based population of patients with CABG underwent stress SPECT or echocardiography during median follow-up of 8.9 years. Despite that approximately 75% of the results of stress imaging studies were abnormal, subsequent referral for coronary angiography within 180 days was low (13.3%), and the yield for repeated revascularization was very low (4.4%).     

Diagnosis of vasospastic angina by hyperventilation and cold-pressor stress echocardiography: comparison to I-MIBG myocardial scintigraphy.

OBJECTIVES: We assessed the usefulness of hyperventilation and cold-pressor stress echocardiography in the diagnosis of vasospastic angina compared with that of iodine-123 metaiodobenzylguanidine (123I-MIBG) myocardial scintigraphy. BACKGROUND: Various noninvasive methods have been used to detect vasospastic angina, but they are not very sensitive in the diagnosis of vasospastic angina. 123I-MIBG images and stress echocardiography have recently been proposed as a useful tool for detecting vasospastic angina. METHOD: Thirty patients (21 males and 9 females, mean age: 52 +/- 14 years) who complained of rest angina were enrolled for this study. The hyperventilation and cold-pressor stress echocardiography test consisted of hyperventilation for 6 minutes, followed by cold water pressor for 2 minutes under continuous electrocardiographic and echocardiographic monitoring. Left ventricular regional wall motion by echocardiogram was analyzed by using the 16-segment model, and wall motion ranging from normokinesis to dyskinesis was evaluated visually in each segment. Single-photon emission computed tomography images of 123I-MIBG myocardial scintigraphy were divided into 26 segments. Defect scores were established using the 4 grades. The echocardiographic criteria for coronary spasm was worsening wall motion and the scintigraphic criteria was defect score more than moderately reduced. Acetylcholine was selectively injected into the right coronary artery (20 microg and 50 microg) and left coronary artery (20 microg, 50 microg, and 100 microg). RESULTS: Of 30 patients, 20 patients had coronary spasm on coronary angiography with an intracoronary injection of acetylcholine, whereas 10 patients showed no spasm. Multivessel spasms were observed in 15 patients. Sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy of hyperventilation and cold-pressor stress echocardiography for diagnosing in patients with vasospastic angina were 90%, 90%, 95%, 82%, and 90%, respectively. However, those of 123I-MIBG myocardial scintigraphy for diagnosing in patients with vasospastic angina were 90%, 40%, 75%, 67%, and 73%, respectively. The specificity of hyperventilation and cold-pressor stress echocardiography was significantly higher than that of 123I-MIBG myocardial scintigraphy (P <.05). CONCLUSION: The specificity of hyperventilation and cold-pressor stress echocardiography in diagnosing coronary spasm were higher than that shown by 201I-MIBG myocardial scintigraphy.     

Effects of pulmonary thromboendarterectomy on right-sided echocardiographic parameters in patients with chronic thromboembolic pulmonary hypertension

OBJECTIVE: To determine the echocardiographic changes in the heart at 3 months and 1 year after pulmonary thromboendarterectomy (PTE) in patients with chronic thromboembolic pulmonary hypertension (CTEPH). PATIENTS AND METHODS: Thirty-two adult patients who underwent PTE for CTEPH at the Mayo Clinic in Rochester, Minn, from 1997 to 2003 were included in the study. All underwent transthoracic echocardiography before surgery. Follow-up echocardiography was performed within 3 months of surgery in 28 patients and 1 year postoperatively in 17 patients. The results were compared with baseline data. RESULTS: Within 3 months after PTE, the right ventricular end-diastolic area decreased from 38.4 +/- 12.8 cm2 to 32.5 +/- 10.4 cm2 (mean difference, 5.8 +/- 10.4 cm2; P = .02). The right ventricular end-systolic area decreased from 30.4 +/- 12.1 cm2 to 24.1 +/- 8.6 cm2 (mean difference, 6.3 +/- 10.1 cm2; P = .008). The right ventricular systolic pressure decreased significantly from 92.6 +/- 22.0 mm Hg to 55.0 +/- 19.8 mm Hg (mean difference, 40.0 +/- 24.8 mm Hg; P < .001). Tricuspid regurgitation (TR) improved from a mean grade of 2.5 +/- 1.2 to 1.2 +/- 1.1 (mean difference, 1.5 +/- 1.0; P < .001). At 12 months, the right ventricular end-diastolic area, right ventricular end-systolic area, right ventricular systolic pressure, and TR also were significantly lower than baseline values. CONCLUSION: In patients with CTEPH who undergo PTE, echocardiographic measurements of right ventricular size, systolic pressure, and TR show significant improvement immediately after surgery, which is sustained for up to 1 year after surgery.     

Biphasic response to dobutamine predicts improvement of left ventricular dysfunction after revascularization: correlation with positron emission and rest-redistribution 201Tl tomographies

BACKGROUND: Dobutamine echocardiography (DSE), positron emission tomography (PET) and 201Tl-single photon emission computed tomography (SPECT) have been used to identify myocardial viability. There are few reports, however, that compare high doses DSE with myocardial metabolic and perfusion imaging techniques in the same patient population. The aim of this study was to determine the correlation between high doses DSE, metabolic PET and 201Tl-SPECT imaging to predict the recovery of function after revascularization in patients with severe left ventricular (LV) dysfunction. METHODS: Twenty-five patients underwent DSE (up to 40 microg/kg/min), rest and 4-hour redistribution 201Tl SPECT, rest 13N-ammonia and 18fluoro-deoxy-glucose PET imaging and coronary angiography 7-10 days before surgical revascularization. A follow-up 2D-echocardiography was performed 6 weeks after surgery. RESULTS: Of the 109 successfully revascularized segments with severe dysfunction, 62 (57%) improved. LV ejection fraction increased from 30 +/- 10% to 42 +/- 13 at follow-up (p < 0.05). 201Tl SPECT, PET and the presence of contractile reserve determined by DSE had a similar sensitivity (77-87%) to predict recovery of function, but specificity was higher for the PET mismatch pattern and biphasic DSE (85-89%) than for any of the 201Tl viability patterns (19-64%). The highest positive predictive values were obtained by biphasic DSE and PET mismatch pattern (78-79%) compared to all other criteria (54-67%). In a multivariate model, which included evidence of viability by all imaging modalities, biphasic response was the best predictor of regional recovery of function (Odds ratio, OR: 9.9, 95% confidence intervals, 95% CI: 3.5-27.8). CONCLUSIONS: Although DSE and PET had overall comparable results, the presence of contractile reserve by the biphasic response to dobutamine was a best predictor for the improvement of LV contractile function in this group of patients.     

Noninvasive assessment of left and right internal mammary artery graft patency with high-frequency transthoracic echocardiography.

OBJECTIVES: The aim of this study was (1) to visualize internal mammary artery grafts (IMAG) on coronary artery by transthoracic echocardiography and (2) to assess the patency of the grafts. METHODS: Twenty-three patients (21 men, 56 +/- 6 years) with previous coronary artery bypass grafting were studied at baseline and after they underwent low-dose dipyridamole infusion. The parameters obtained were systolic (SPV) and diastolic (DPV) peak velocities and their ratio (DPV/SPV); the dipyridamole infusion to baseline ratio of DPV was an index of IMAG blood flow reserve (FR). Two groups of patients were selected at baseline: group A, (n = 12) with a DPV/SPV >1, and group B (n = 11), with a DPV/SPV <1. RESULTS: The IMAG was identified in all patients. Intraluminal flow signals obtained with pulsed wave Doppler showed a biphasic pattern (1 systolic and 1 diastolic wave). After dipyridamole infusion was administered, flow velocities increased in 11 of 12 patients in group A and in 5 of 11 patients in group B. In group A the DPV/SPV increased from 1.79 +/- 0.47 to 1.8 +/- 0.43 (P = not significant), and the FR was 1.8 +/- 0.4. In group B the DPV/SPV increased from 0. 46 +/- 0.05 to 0.5 +/- 0.09 (P = not significant), and the FR was 1. 3 +/- 0.41. Coronary angiography showed the graft patency in all patients in group A and in 5 patients in group B with increased flow velocity after dipyridamole infusion. In the identification of graft stenosis at baseline, DPV/SPV showed 100% sensibility and 58% specificity, and FR showed 92% sensibility and 84% specificity. CONCLUSION: Doppler echocardiographic evaluation of the IMAG is a simple noninvasive method to assess the functional impairment of the vessel.     

Single-point cardiac troponin T at coronary care unit discharge after myocardial infarction correlates with infarct size and ejection fraction

BACKGROUND: One of the major concerns in replacing creatine kinase MB (CK-MB) with cardiac troponins is the lack of evidence of the ability of troponins to estimate the size of acute myocardial infarction (AMI). We investigated the ability of a single measurement of cardiac troponin T (cTnT) at coronary care unit (CCU) discharge to estimate infarct size and assess left ventricular (LV) function in AMI patients. METHODS: We studied 65 AMI patients in whom infarct size was estimated by CK-MB peak concentrations and gated single-photon emission computed tomography (SPECT) myocardial perfusion using technetium-99m sestamibi and LV function by SPECT imaging. Measurements of cTnT and SPECT were performed 72 h (median) after admission (range, 40-160 h). SPECT was also repeated 3 months later. RESULTS: We found a significant correlation between cTnT and both the peak CK-MB concentrations (r = 0.76; P <0.001) and the perfusion defect size at SPECT (r = 0.62; P <0.001). cTnT was inversely related to LV ejection fraction (LVEF) assessed both early (r = -0.56; P <0.001) and 3 months after AMI (r = -0.70; P <0.001). cTnT >2.98 micro g/L predicted a LVEF <40% at 3 months with a sensitivity of 86.7%, specificity of 81.4%, and a likelihood ratio for a positive test of 4.7 (95% confidence interval, 4.0-5.4). CONCLUSIONS: A single cTnT measurement at CCU discharge after AMI is useful as a noninvasive estimate of infarct size and for the assessment of LV function in routine clinical setting.     

Contrast harmonic color Doppler left ventriculography: machine-interpreted left ventricular ejection fraction compared with equilibrium-gated radionuclide ventriculography.

BACKGROUND: Multi-gated acquisition (equilibrium-gated radionuclide ventriculography) (MUGA) is considered the gold standard for measuring left ventricular ejection fraction (LVEF) because it is accurate, machine interpreted, and reproducible. Echocardiographic LVEF measurements are subject to variability in image acquisition and interpretation and to the limitations of 2-dimensional (2D) versus 3-dimensional imaging. GOAL: The shortcomings of traditional echocardiography may be addressed by combining multiplane 2D harmonic imaging, echocardiographic contrast, color Doppler ultrasonography, and digital image processing to create a new imaging modality: contrast harmonic color Doppler left ventriculography. METHODS: We compared the accuracy of a new method for measuring LVEF that allows for machine interpretation and uses contrast-enhanced intermittent harmonic color Doppler ultrasonography (CHCD). Quantitative LVEF measurements by hand-traced harmonic 2D echocardiography, contrast-enhanced harmonic 2D echocardiography, CHCD, and machine-interpreted CHCD were compared with MUGA in 35 patients. RESULTS: Contrast-enhanced intermittent harmonic color Doppler provided images with vivid endocardial definition in all patients, but hand-traced harmonic 2D echocardiography and contrast-enhanced harmonic 2D echocardiography had inadequate images in 9% of patients. The MUGA LVEF range was 0. 09 to 0.70. All echocardiographic methods showed excellent correlation with the MUGA LVEF (R (2) > 0.96), but the CHCD method had the best limits of agreement. CONCLUSIONS: Contrast-enhanced intermittent harmonic color Doppler LVEF correlates with MUGA at least as well as traditional noncontrasted echocardiography, but it provides diagnostic images in a greater proportion of patients. The CHCD images have vivid endocardial delineation and can be machine interpreted.