Impact of occluder device type on success of percutaneous closure of atrial septal defects--a medium-term follow-up study.

OBJECTIVE: To identify differences between various occluder types regarding thromboembolic event rates and existence of residual shunts during medium-term follow-up. METHODS: Three hundred nine consecutive patients with presumed paradoxical embolism and scheduled for percutaneous closure of patent foramen ovale or atrial septal defect between 1997 and 2006 were considered for this study. Device implantation failed in seven patients (nonstable device position), so 302 patients (46 +/- 12 years, 190 males) formed the study group using Amplatzer (n = 208), Starflex (n = 61), and Cardiastar (n = 33) occluders. Follow-up transesophageal echocardiography was performed 1, 3, and 6 months after implantation. RESULTS: Periinterventional complications occurred in two patients (cardiac arrhythmias). There were more residual shunts in the Starflex and Cardiastar group than in the Amplatzer group at 6-month follow-up (8/61 vs. 7/33 vs. 8/208, P = 0.0005). Performing logistic regression, the type of occluder device was a significant risk factor for the presence of residual shunt 6 months after implantation (P = 0.0033; Cardiastar vs. Amplatzer OR 6.346, 95% CI 1.998 - 20.156; Starflex vs. Amplatzer OR 4.369, 95% CI 1.444 - 13.222). During mean follow-up of 31 +/- 8 months 16 recurrent thromboembolic events occurred; the annual recurrence was 2.1% for combined end-point stroke, TIA, and peripheral embolism (Amplatzer: 1.3%, Starflex: 3.9%, and Cardiastar: 3.6%, P = 0.0467). The presence of an atrial septal aneurysm was the only significant risk factor (P = 0.0168, OR 3.664, 95% CI 1.263 - 10.630) for the occurrence of thromboembolic events. CONCLUSIONS: Percutaneous closure of patent foramen ovale or atrial septal defect is a safe procedure with little incidence of peri- and postprocedural complications. There is a significant difference between the Amplatzer, Cardiastar, and Starflex occluders in regard to complete closure of the defects and annual recurrence of thromboembolic events.

Serial measurements of whole blood nitrite in an intensive care setting.

Nitrite plays an eminent role in cardiovascular physiology and pathology, mediating hypoxic vasodilation, reducing ischemia-reperfusion injury, and regulating cardiac energetics and function. The role of circulating nitrite in critically ill patients has not been examined so far. To investigate whether whole blood nitrite can be determined reproducibly in an intensive care setting, 30 patients from a cardiology intensive care unit were enrolled in this study, no matter what the underlying disease. Blood was drawn from an arterial catheter and whole blood nitrite was determined, using a tri-iodide/ozone-based chemiluminescence assay after incubation with a ferricyanide-containing stabilization solution. Whole blood nitrite levels ranged from 35 to 1193 nmol/L (mean+/-SEM: 220+/-20 nmol/L). Myocardial infarction was associated with lower whole blood nitrite levels (200+/-53 nmol/L for elevated serum CK MB levels vs 432+/-95 nmol/L in the normal CK MB range, p=0.039). Neither impaired kidney function nor an inflammatory state was associated with higher or lower whole blood nitrite levels. In conclusion, whole blood nitrite can be measured easily and reproducibly in critically ill patients, regardless of renal function and inflammation. The origin of decreased nitrite levels in myocardial infarction is currently unclear and needs to be further elucidated.

Myocardial contrast echocardiography versus Thrombolysis In Myocardial Infarction score in patients presenting to the emergency department with chest pain and a nondiagnostic electrocardiogram.

OBJECTIVES: We hypothesized that regional function (RF) and myocardial perfusion (MP) are superior to the Thrombolysis In Myocardial Infarction (TIMI) score for diagnosis and prognostication in patients presenting to the emergency department (ED) with chest pain (CP) and a nondiagnostic electrocardiogram. BACKGROUND: Rapid diagnosis and prognostication is difficult in patients presenting to the ED with suspected cardiac CP. METHODS: Contrast echocardiography was performed to assess RF and MP on 957 patients presenting to the ED with suspected cardiac CP and a nondiagnostic electrocardiogram. A modified TIMI (mTIMI) score was calculated from six immediately available variables. A full TIMI score also was derived after troponin levels were able to be accessed adequately. Follow-up was performed for early (within 24 h), intermediate (30 day), and late primary (death and myocardial infarction) or secondary (unstable angina and revascularization) events. RESULTS: The mTIMI score was unable to discriminate between intermediate- compared to high-risk patients at any follow-up time point, whereas only 2 of 523 patients with normal RF had an early primary event. Regional function provided incremental prognostic value over mTIMI scores for predicting intermediate and late events. In patients with abnormal RF, MP further classified patients into intermediate- and high-risk groups. The full TIMI score could not improve upon these results at any follow-up time point. CONCLUSIONS: Contrast echocardiography can rapidly and accurately provide short-, intermediate-, and long-term prognostic information in patients presenting to the ED with suspected cardiac CP even before serum cardiac markers are known. Integrating contrast echocardiography into the ED evaluation of CP may improve the risk stratification of such patients.

Association of C-reactive protein and myocardial perfusion in patients with ST-elevation acute myocardial infarction.

This study sought to evaluate the relation between C-reactive protein (CRP) on admission of patients with acute myocardial infarction (AMI) and myocardial perfusion as defined by postintervention angiographic myocardial blush grade (MBG) and their impact on subsequent mortality. The patient population comprised 191 consecutive patients with AMI undergoing PTCA within 12h of symptom onset on a native vessel. Patients were divided based on the CRP level on admission (Rolf Greiner BioChemica, Germany, cutpoint for the assay CRP: 5mg/l) into a group with elevated CRP (>or=5mg/l) and a group with normal CRP. Angiographic myocardial blush grade (MBG) after revascularization of the infarct-related artery was determined to evaluate myocardial reperfusion. Revascularization of the infarct-related artery was successful in 176 (92.6%) patients. The frequency of impaired perfusion (MBG 0-2) was higher in the elevated CRP group than in the normal CRP group (74.5% versus 59.7%, respectively, p=0.046). Elevated CRP on admission was an independent predictor of impaired myocardial perfusion (MBG 0-2, OR 1.92, 95% CI 1.02-4.01, p=0.042) in addition to age >70 years. Elevated CRP (OR 2.64, 95% CI 1.26-5.53, p=0.009) and MBG 0-2 (OR 4.58; 95% 1.73-12.20, p=0.002) were independent predictors of mortality during a 22.4+/-15.3 months follow-up in addition to heart rate on admission >100 beats/min (OR 3.07; 95% CI 1.30-7.25, p=0.009). In sequential Cox models, the predictive power of clinical data and MBG for mortality (model chi-squared 18.3) was strengthened by the inclusion of CRP levels (model chi-squared 24.3). In conclusion, there is a relation between elevated admission CRP and impaired reperfusion in the myocardium subtended to the infarct-related artery. The combination of clinical data, myocardial reperfusion levels after primary angioplasty for AMI and admission CRP increases the predictive value for subsequent survival.

Prediction of clinical outcome after mechanical revascularization in acute myocardial infarction by markers of myocardial reperfusion.

OBJECTIVES: We sought to evaluate and compare recently suggested parameters of reperfusion after angioplasty in acute myocardial infarction (AMI) for risk stratification during long-term follow-up. BACKGROUND: Abnormal myocardial perfusion has a detrimental impact on survival. Several parameters of reperfusion have been evaluated in controlled study populations for risk stratification. METHODS: In 253 consecutive patients undergoing intervention in AMI on a native coronary vessel, angiographic myocardial blush grade (MBG), corrected TIMI (thrombolysis in myocardial infarction) frame count (CTFC) and persistent ST-segment elevation (STE) were determined to evaluate reperfusion. This was a high-risk population, including referral for treatment failure at a primary center in 29.2%, failed thrombolysis in 22.1% and cardiogenic shock in 13.4% of cases. RESULTS: In addition to age, patient referral, LBBB and heart rate on admission, MBG 0 to 1 (odds ratio [OR] = 3.23, p < 0.001), CTFC (OR = 1.01, p = 0.015) and persistent STE >2 leads (OR = 3.46, p = 0.010) were univariate predictors of mortality during a 22.1 +/- 15.6 months follow-up. Myocardial blush grade 0 to 1 (OR = 2.17, p = 0.033) and persistent STE (OR = 3.61, p = 0.017) persisted as independent predictors of mortality, whereas CTFC failed. Differences in mortality between reperfusion groups at 30 days remained throughout the complete follow-up. In sequential Cox models, the predictive power of clinical data alone for mortality (model chi-squared 55.8) was strengthened by adding MBG (model chi-squared 64.2) and ECG postintervention (model chi-squared 69.2). CONCLUSIONS: Myocardial blush grade 0 to 1 and persistent STE are independent predictors for long-term mortality after angioplasty in AMI. Corrected TIMI frame count is a less powerful predictor. Combining both parameters to consider quality of reperfusion in the myocardium at risk and extent of the infarct zone increases the predictive power.

Detection of myocardial viability by contrast echocardiography in acute infarction predicts recovery of resting function and contractile reserve.

OBJECTIVES: We sought to determine whether myocardial contrast echocardiography (MCE) performed before and early after primary coronary stenting (PCS) in patients with acute myocardial infarction (AMI) could predict recovery of resting left ventricular systolic function and contractile reserve. BACKGROUND: Myocardial contrast echocardiography can be used to assess perfusion within the risk area before PCS and the extent of necrosis soon after PCS. METHODS: In 30 patients with AMI, MCE and two-dimensional echocardiography were performed before PCS and 3 to 5 days and 4 weeks after PCS. Contractile reserve was assessed by dobutamine echocardiography at four weeks in patients with persistent severe wall-motion abnormalities. RESULTS: Of segments without perfusion at 3 to 5 days, 95% had severe hypokinesis to akinesis at 4 weeks. Of segments with normal perfusion at 3 to 5 days, 90% had normal wall motion or mild hypokinesis at 4 weeks, whereas those with partial perfusion at 3 to 5 days were evenly divided between normal wall motion, hypokinesis, and akinesis. In segments with persistent severe wall-motion abnormalities at four weeks, contractile reserve was found in >80% of segments with perfusion, compared with only 10% of segments without detectable perfusion (p < 0.01). The presence of myocardial perfusion by MCE before PCS was associated with maintained or improved perfusion at 3 to 5 days and eventual recovery of resting wall motion. CONCLUSIONS: Myocardial contrast echocardiography performed early after PCS provides information on the extent of infarction, and hence the likelihood for recovery of resting systolic function or contractile reserve. The presence of perfusion before PCS, from either collateral or antegrade flow, predicts the maintenance of perfusion and recovery of systolic function.

Repeated assessment of coronary flow velocity pattern in patients with first acute myocardial infarction.

OBJECTIVES: The aim of this study was to evaluate the coronary blood flow velocity pattern immediately and 24 h after percutaneous transluminal coronary angioplasty (PTCA) for acute myocardial infarction (AMI) in relation to myocardial reperfusion and follow-up left ventricular (LV) function. BACKGROUND: Analysis of coronary blood flow velocity pattern after AMI may provide information about microvascular damage and the occurrence of a reperfusion injury. METHODS: Measurement of coronary blood flow velocity pattern was performed immediately after PTCA and after 24 h in 25 patients with first AMI using a Doppler guidewire. Measurements were related to reperfusion determined by intravenous myocardial contrast echocardiography (MCE) performed before PTCA and at 24 h and to LV function at four weeks. RESULTS: Using MCE, 13 patients showed reperfusion and 12 patients showed nonreperfusion. Compared with patients with reperfusion, patients with MCE nonreperfusion had a lower systolic peak flow velocity immediately after PTCA (10.0 +/- 0.3 cm/s vs. 19.3 +/- 0.8 cm/s, respectively) and after 24 h (12.3 +/- 0.4 cm/s vs. 21.3 +/- 0.1 cm/s, respectively, p = 0.0022), more frequent early systolic retrograde flow (6/12 vs. 0/13, p = 0.0052 immediately after PTCA and 24 h later) and a shorter diastolic deceleration time immediately after PTCA (483 +/- 6 ms vs. 737 +/- 0 ms, respectively) and after 24 h (551 +/- 9 ms vs. 823 +/- 2 ms, respectively, p = 0.0091). Similarly, patients with impaired LV function at four weeks had altered coronary flow pattern compared with patients with preserved function. The coronary flow velocity pattern showed a tendency for improvement after 24 h in the reperfusion and the nonreperfusion groups. CONCLUSIONS: The coronary flow velocity pattern immediately and 24 h after PTCA for AMI relates to myocardial perfusion determined by MCE and LV function at four weeks. The flow velocity pattern shows slight improvement during the first 24 h after revascularization, indicating the absence of a major reperfusion injury.

Myocardial perfusion assessment in patients with medium probability of coronary artery disease and no prior myocardial infarction: comparison of myocardial contrast echocardiography with 99mTc single-photon emission computed tomography.

BACKGROUND: No previous studies have compared myocardial contrast echocardiography (MCE) and single-photon emission computerized tomography (SPECT) for the detection of coronary artery disease (CAD) in patients with a medium likelihood of CAD. This study was developed to test the hypothesis that MCE is superior to SPECT for the detection of CAD. METHODS: Fifty-five patients with a medium probability of CAD and no previous myocardial infarction were recruited. Results of MCE and SPECT were compared to quantitative coronary arteriography, where CAD was defined as >50% stenosis. Each patient was examined for the anterior and posterior circulations. RESULTS: On a coronary circulation basis (n = 110), the sensitivity of MCE was significantly greater than that of SPECT for the detection of CAD (86% vs 43%, P <.0001). However, the specificities were similar (88% and 93%, P =.52). Both techniques were marginally more accurate in the anterior compared to the posterior circulation (88% vs 76%, P =.07 for MCE and 79% vs 63%, P =.19, for SPECT). On a patient basis (n = 55), MCE had a higher sensitivity than SPECT for the detection of CAD (83% vs 49%, P <.05). Although specificity tended to be higher for SPECT than MCE (92% vs 58%), it was not significant (P =.33). When CAD was defined as >40% coronary stenosis, the specificity of MCE increased to 83% without any change in sensitivity. CONCLUSION: In this preliminary study, MCE was found to be superior to SPECT during dipyridamole stress for the diagnosis of CAD in patients with a medium pretest probability of CAD. Larger studies are required to confirm these findings.

Usefulness of myocardial blush grade early and late after primary coronary angioplasty for acute myocardial infarction in predicting left ventricular function.

This study sought to analyze the evolution of myocardial perfusion during follow-up after primary angioplasty for acute myocardial infarction (AMI) and relate it to final left ventricular (LV) function. In 101 patients with a first AMI, angiographic myocardial blush grade (MBG) was analyzed immediately after intervention and at follow-up 7.5 +/- 5.6 months later. Cine ventriculography was performed at follow-up angiography to define LV function. Five patients had occluded stents or flow-limiting restenosis. In the remaining patients, myocardial perfusion at follow-up, as defined by MBG, was persistently abnormal in 19 patients (20%), had become normalized from previously abnormal MBG in 30 patients (31%), remained normal in 40 patients (42%), and deteriorated from normal to abnormal in 7 patients (7%). Patients with improvement of abnormal blush determined immediately after intervention to normal blush at follow-up (n = 30) compared with patients with persistently abnormal blush (n = 19) had a better LV ejection fraction at follow-up (53.7 +/- 11.1 vs. 37.4 +/- 9.7%, p <0.001). Evolution of MBG had a better predictive value for LV ejection fraction at follow-up than acute MBG only. Multivariate analysis proved evolution of MBG from AMI to follow-up to be an independent predictor of LV function (R(2) = 0.177, p <0.001) in addition to the initial size of jeopardized myocardium as defined by the sum of ST-segment elevation (R(2) = 0.138, p = 0.001) and infarct location (R(2) = 0.044, p = 0.033). In conclusion, tissue reperfusion after angioplasty for AMI is characterized by frequent improvement over time, as indicated by repeated MBG analysis. Patients with recovery of perfusion have better, final LV function.

Assessment of the vascularity of a left ventricular mass using myocardial contrast echocardiography.

In addition to a thrombus, an intracardiac mass lesion can represent a primary cardiac tumor, or a metastatic lesion to the heart. The echocardiographic appearance and location of the mass, as well as the associated clinical scenario provide useful clues regarding cause, but these echocardiographic features alone may not always be diagnostic. Because most benign cardiac tumors are relatively avascular, the vascularity of a mass may be a feature that can help differentiate benign from malignant tumors. We present a case of a patient with a history of malignant melanoma who was found incidentally to have a cardiac mass on echocardiography. Contrast echocardiography (CE) was used to evaluate the vascularity of the mass. This case is compared with another patient with an apical thrombus, which represents an "avascular" intracardiac structure.

Intravenous myocardial contrast echocardiography predicts left ventricular remodeling in patients with acute myocardial infarction.

BACKGROUND: This study evaluated the ability of intravenous myocardial contrast echocardiography (MCE) performed in the setting of acute myocardial infarction for prediction of left ventricular (LV) remodeling. METHODS: Intravenous MCE was performed immediately before, 1 hour, and 24 hours after primary percutaneous transluminal coronary angioplasty (PTCA) in 35 patients with a first myocardial infarction. The MCE was used to define the relative perfusion defect size (in %; relMCD). Two-dimensional echocardiography was performed directly after angioplasty and after 4 weeks to determine LV end-diastolic volumes (LVEDV). The increase in LVEDV at 4 weeks defined a remodeling (> 15% increase) and a nonremodeling group (< or = 15% increase). RESULTS: Patients with remodeling had larger relMCD before (22.0 +/- 16.1 vs 8.0 +/- 11.9, P =.015), 1 hour (20.0 +/- 13.0 vs 4.9 +/- 11.6, P =.001), and 24 hours after PTCA (22.9 +/- 14.1 vs 1.2 +/- 2.8, P <.001). There was a significant correlation between relMCD 24 hours after PTCA and the increase in LVEDV at 4 weeks (r = 0.648; P <.001). Receiver operating characteristic (ROC) curve analysis revealed a relMCD at 24 hours of 5.1% or more to predict remodeling with a sensitivity of 94% and a specificity of 87% (area under ROC curve = 0.917; SE = 0.054). Multivariate analysis demonstrated relMCD at 24 hours to be the only predictor of remodeling (odds ratio = 173.4; P =.022). CONCLUSION: The size of the persistent MCE perfusion defect after revascularization for acute myocardial infarction has a high predictive value for LV remodeling during a 4-week follow-up period.

TNF-α, myocardial perfusion and function in patients with ST-segment elevation myocardial infarction and primary percutaneous coronary intervention.

AIMS: To characterize the time course of tumor necrosis factor-α (TNF-α) serum levels along with myocardial perfusion and contractile function in patients with ST-segment elevation myocardial infarction (STEMI) and successful primary percutaneous coronary intervention (PCI). METHODS: Serum levels of TNF-α, interleukin 6 (IL-6), and C-reactive protein (CRP) were measured in 42 patients with STEMI before, one and 6 days after successful PCI. Myocardial perfusion was assessed by contrast-enhanced echocardiography (ceEcho), contractile function by unenhanced two-dimensional (2DE) and real-time three-dimensional echocardiography. In a subset of 18 patients, infarct size was quantified by late gadolinium enhancement cardiovascular magnetic resonance imaging (LGE-CMR) on day six. RESULTS: TNF-α serum levels were in the upper normal range within the first 12 h from symptom onset and increased continuously until day six, while IL-6 and CRP increased subsequently with a peak on day one after STEMI. Serum TNF-α on day one after PCI correlated with perfusion defects, wall motion abnormalities, and infarct size (ceEcho: r = 0.52, p = 0.005; 2DE: r = 0.56, p = 0.002; LGE-CMR: r = 0.83-0.86; p < 0.0001). Using multiple regression linear analysis, infarct size on day six was predicted by serum TNF-α 1 day after PCI (p = 0.006, adjusted R (2) 0.638). CONCLUSION: Our data reflect the clinical significance of early TNF-α elevation in patients with STEMI and primary PCI (Controlled Clinical Trials number, NCT00529607).

Fractional flow reserve of infarct-related arteries identifies reversible defects on noninvasive myocardial perfusion imaging early after myocardial infarction.

OBJECTIVES: We hypothesized that fractional flow reserve (FFR) of an infarct-related artery (IRA) early after myocardial infarction (MI) identifies inducible ischemia on noninvasive imaging. BACKGROUND: Early after MI, IRAs frequently have angiographically indeterminant lesions. Whether FFR can detect reversible perfusion defects early after MI when dynamic microvascular abnormalities are present is not known. METHODS: Rest and dipyridamole (DP)-stress 99mTc sestamibi single-photon emission computed tomography (SPECT) were performed in 48 patients 3.7 +/- 1.3 days after MI, with 23 patients undergoing concurrent myocardial contrast echocardiography (MCE). Angiography, FFR, and percutaneous coronary intervention (PCI) of the IRA (as necessary) were subsequently performed. Follow-up SPECT was performed 11 weeks after PCI to identify true reversibility on baseline SPECT. RESULTS: The sensitivity, specificity, positive and negative predictive value, and concordance of FFR < or =0.75 for detecting reversibility on SPECT were 88%, 50%, 68%, 89%, and 71% (chi-square <0.001), respectively; which improved to 88%, 93%, 88%, 93%, and 91% (chi-square <0.001), respectively, for the detection of true reversibility. The corresponding values of FFR < or =0.75 for detecting reversibility on DP-MCE were 90%, 100%, 100%, 75%, and 93% (chi-square <0.001), respectively, and on either SPECT or MCE were 88%, 93%, 91%, 91%, and 91% (chi-square <0.001), respectively. The optimal FFR value for discriminating inducible ischemia on noninvasive imaging was 0.78. CONCLUSIONS: Fractional flow reserve of the IRA accurately identifies reversibility on noninvasive imaging early after MI. These findings support the utility of FFR early after MI.

Comparison of the 6-minute walk test with established parameters for assessment of cardiopulmonary capacity in adults with complex congenital cardiac disease.

BACKGROUND: Objective assessment of the cardiopulmonary capacity in patients with complex congenital cardiac disease often remains difficult in clinical practice. The cardiopulmonary exercise test and determination of the levels of brain natriuretic peptide in the plasma are established tests, but expensive. The 6-minute walk test is also validated, but has not often been used in patients with heart failure due to congenital heart disease, nor compared with other tests. We sought to compare its value with the results of cardiopulmonary exercise testing and measuring the levels of brain natriuretic peptide in the plasma. METHODS: We carried out a standardized 6-minute walk test in 31 patients with complex congenital cardiac disease on the same day that they underwent cardiopulmonary exercise testing and determination of levels of brain natriuretic peptide in the plasma. Of the patients, 7 had functionally univentricular hearts, 9 had transposition, 9 had tetralogy of Fallot, 3 had common arterial trunk, and 3 had pulmonary atresia with intact interventricular septum. Uptakes of oxygen at peak exercise, and at the anaerobic threshold, were determined using cardiopulmonary exercise testing, and classified as suggested by Weber. The 6-minute walk test was performed according to a standard protocol. RESULTS: There was a significant correlation between brain natriuretic peptide, oxygen uptakes at peak exercise and 6-minute walk. The correlation between the 6-minute walk test and oxygen uptakes at the anaerobic threshold, however, was not significant. CONCLUSIONS: The 6-minute walk test can be performed easily, is inexpensive, widely available, and correlates well with measurements of brain natriuretic peptide and cardiopulmonary exercise testing, even in patients with corrected or palliated congenital cardiac malformations. A cut-off value of 450 metres in the 6-minute walk test allows a semi-quantitative classification in analogy to the classification suggested by Weber for cardiopulmonary exercise testing, and to a level of brain natriuretic peptide in the plasma of less or more than 100 picograms per millilitre.

Regional left ventricular perfusion and function in patients presenting to the emergency department with chest pain and no ST-segment elevation.

AIMS: We hypothesized that the assessment of left ventricular regional function (RF) and myocardial perfusion (MP) will provide incremental value over routine evaluation in patients who present to the emergency department (ED) with chest pain (CP) and no ST-segment elevation. METHODS AND RESULTS: In addition to routine clinical evaluation, patients with suspected cardiac CP and no ST-segment elevation were evaluated in the ED for RF and MP using contrast echocardiography (CE). Cardiac-related death, acute myocardial infarction, unstable angina pectoris, congestive heart failure (CHF), and revascularization were considered as events within 48 h (early). Of the 1017 patients studied, 166 (16.3%) had early events. Adding RF increased the prognostic information of clinical and EKG variables significantly (Bonferroni corrected P<0.0001) for predicting these events. When MP was added, significant additional prognostic information was obtained (Bonferroni corrected P=0.0002). All patients were followed for a median of 7.7 months (25th-75th percentiles: 2.7-12.5) Of these, 292 (28.7%) had events. Adding RF increased the prognostic information of clinical and EKG variables for determining the risk of events significantly (Bonferroni corrected P<0.0001), which was further increased by adding MP (Bonferroni corrected P<0.0001). CONCLUSION: Early assessment of RF on CE adds significant diagnostic and prognostic value to routine evaluation in patients presenting to the ED with suspected cardiac CP and no ST-segment elevation. MP provides additional significant value. CE could be a valuable tool in the early triage and management of CP patients presenting to the ED.

Quantitative evaluation of myocardial perfusion in patients with revascularized myocardial infarction: comparison between intravenous myocardial contrast echocardiography and 99mTc-sestamibi single photon emission computed tomography.

AIMS: This two-center study compared quantitative segmental perfusion mapping by intravenous myocardial contrast echocardiography (ivMCE) and scintigraphy (SPECT) in patients in the subacute phase of myocardial infarction (AMI). METHODS AND RESULTS: Sixteen patients underwent ivMCE using 1:1 intermittent harmonic imaging 24 h after first AMI treated with PTCA and stenting. Apical contrast echocardiograms were obtained after the injections of Sonazoid. Baseline-corrected peak myocardial videointensity (bcPMVI) was determined automatically in 16 segments. Resting 99mTc-sestamibi SPECT was performed within one day after ivMCE. SPECT images were reoriented matching the ivMCE views, and divided into the same segments as in ivMCE, from which mean count rate values were obtained. After exclusion due to artifacts or attenuation, 208/256 (82%) segments remained for analysis. Normalized SPECT count rate and bcPMVI correlated linearly: bcPMVI = 1.237 x SPECT - 35; r = 0.74, p < 0.0001. The relation remained identical in subgroup analysis based on participating center, echocardiographic view, perfusion territory, infarct zone, or function. Using SPECT as reference, mean bcPMVI was 77+/-19% in normal segments, 53+/-29% in mild-moderate defects and 25+/-18% in severe defects (p<0.001 for all comparisons). CONCLUSION: The videointensity increase observed in quantitative ivMCE clearly correlated with SPECT tracer uptake. This further substantiates the use of ivMCE as a valid technique for myocardial perfusion imaging.

Impact of flow level on coronary flow velocity pattern. A doppler flow study in patients with first acute myocardial infarction.

Analysis of coronary flow velocity pattern has been used to assess microvascular function post acute myocardial infarction (AMI). This study sought to analyze whether the flow level has an impact on parameters of coronary flow velocity pattern. Parameters of coronary flow velocity pattern were determined at baseline and during increased flow due to maximal hyperemia induced by adenosine in 25 patients after PTCA for first AMI using Doppler flow wires. Patients were divided into those with depressed (global wall motion index (GWMI) > or = 1.5; n = 14) and those with preserved (GWMI < 1.5; n = 11) left ventricular (LV) function at 4 weeks. Coronary flow velocity pattern at rest was different between patients with depressed and patients with preserved LV function at follow-up. A difference in flow pattern between the groups remained at increased flow level. However, increase of flow altered parameters of flow pattern. Diastolic deceleration rate (DSR) increased for patients with preserved LV function (53.7+/-25.6 at baseline vs. 67.0+/-29.8 cm/s2 with adenosine) and depressed LV function (95.3+/-58.6 vs. 110.7+/-61.4 cm/s2, respectively, p = 0.0012). Induction of hyperemia resulted also in increased systolic and diastolic peak flow velocity and diastolic deceleration time (DDT). Higher flow had no impact on early systolic retrograde flow, systolic flow duration and diastolic-systolic velocity ratio (DSVR). The coronary flow velocity pattern allows prediction of LV function at 4 weeks after AMI. However, it should be considered that some parameters of the flow velocity pattern are affected by the coronary flow level.