Profound delayed thrombocytopenia presenting 16 days after Abciximab (Reopro®) administration.

Abciximab occasionally causes severe thrombocytopenia. This is variable in severity and usually occurs within hours of administration but has been reported to present up to 8 days later. This report describes a case of life-threatening thrombocytopenia 16 days following Abciximab administration. The patient required supportive transfusions and ultimately improved following dexamethasone and intravenous immunoglobulin. The case represents the longest delay between Abciximab administration and thrombocytopenia published to date.

Diagnostic and prognostic role of cardiac troponin I (cTnI) measured on the DPC Immulite.

OBJECTIVE: To evaluate the diagnostic and prognostic role of the Immulite cTnI assay for the detection of acute coronary syndromes (ACS). POPULATION: 150 males and 63 females with a median age of 63 years, range 28 to 88, and an interquartile range of 18 years were admitted within 24 h of chest pain and non-ST segment elevation ACS were studied. The median onset of symptoms was 3 h (range 0-23). METHODS: Venous samples were taken on admission (t = 0) and at 24 h (t = 24). The serum samples were assayed for CK, CK-MB and cTnT on an Elecsys 1010 (Roche Diagnostics, Lewes, UK). The cTnT assay CV was 5.5% at 0.32 microg/l and 5.4% at 6.0 microg/l, and the detection limit was 0.01 microg/l with an upper limit of 25 microg/l. For cTnI using the Immulite (DPC, Gwynedd, Wales), the detection limit was 0.1 microg/l, and the upper limit was 180 microg/l. Final diagnostic categorization was performed by both WHO and European Society of Cardiology criteria using cTnT as the diagnostic cardiac biomarker. Patients were followed for the major adverse cardiac events (MACE), endpoints cardiac death, AMI or need for urgent revascularization. ROC curves were constructed using final diagnosis. Outcome prediction was assessed by ROC curves and Kaplan-Meier survival curves. RESULTS: Both methods had equivalent diagnostic efficiency using WHO criteria for AMI. When ESC criteria were used the AUC for admission and 24 h cTnT and cTnI values were 0.945 vs. 0.910, P = 0.20 and 0.998 vs. 0.937, P = 0.005, respectively. Both methods predicted outcome as either death or MI or MACE and were not significantly different. CONCLUSION: The Immulite cTnI assay can be used for diagnosis and risk stratification in patients admitted with non-ST segment elevation acute coronary syndromes.

Myocardial viability assessed by dobutamine stress echocardiography predicts reduced mortality early after acute myocardial infarction: determining the risk of events after myocardial infarction (DREAM) study.

OBJECTIVE: To establish further the role of dobutamine stress echocardiography (DSE) in prognostication of outcome early after acute myocardial infarction (AMI) METHODS: Consecutive patients presenting with AMI were screened for inclusion into the study. 212 stable consenting patients underwent DSE a mean (SD) of 4.8 (1.5) days after AMI. Patients were then followed up for 803 (297) days. RESULTS: The mean (SD) resting systolic wall thickening index (SWTI) was 1.6 (0.4), 44% patients had evidence of viability at low dose, and 38% had evidence of ischaemia. During the follow up period 27 (13%) patients died and 16 (8%) had a non-fatal AMI. Independent predictors of both mortality and combined mortality and non-fatal AMI were age (hazard ratio (HR) 1.04/year, p = 0.01, and HR 1.03/year, p = 0.04, respectively) and SWTI at low dose (HR 3.6, p < 0.01, and HR 2.5, p = 0.02, respectively). Low dose DSE provided incremental information over clinical and resting left ventricular function data for predicting death and non-fatal AMI. For patients who were not revascularised SWTI at peak dose dobutamine was the only independent predictor of mortality. CONCLUSION: DSE is a powerful predictor of outcome in stable survivors of AMI. The presence of myocardial viability has a positive impact on survival.

Wall thickening assessment with tissue harmonic echocardiography results in improved risk stratification for patients with non-ST-segment elevation acute chest pain.

OBJECTIVES: To demonstrate whether the improved imaging quality gained by using tissue harmonic echocardiography in place of fundamental echocardiography results in the improved risk stratification of patients presenting with non-ST-elevation acute chest pain. METHODS AND RESULTS: Eighty patients with over 30 min of non-ST-elevation chest pain that had lasted less than 6 h were recruited. All patients underwent resting tissue harmonic and fundamental echocardiographic scans. Diagnosis for acute myocardial infarction was made on a 24 h creatine kinase-MB sample. Echocardiographic images were reported by two experienced blinded observers. Patients were followed up at least 4 months after admission. Endpoints included all-cause mortality, non-fatal myocardial infarction and revascularisation procedures. Tissue harmonic echocardiography allowed assessment of all myocardial segments in all patients compared to 43/78 patients ( p<0.001 ) with fundamental echocardiography. A wall thickening abnormality demonstrated on tissue harmonic echocardiography and not fundamental echocardiography was a significant predictor of index myocardial infarction on admission ( p<0.007 ) and for an adverse cardiac event during follow up ( p=0.002 ). CONCLUSIONS: Tissue harmonic echocardiography is superior to fundamental echocardiography for accurate assessment of systolic wall thickening and hence risk stratification for patients presenting with acute chest pain and non-diagnostic electrocardiogram changes.

Real time contrast echocardiography--a new bedside technique to predict contractile reserve early after acute myocardial infarction.

AIMS: Power pulse inversion echocardiography is a new technique by which contrast microbubbles can be visualised in real time within the myocardium, enabling simultaneous assessment of myocardial function and microvascular integrity, which is a prerequisite for myocardial viability. We aimed to determine whether microvascular integrity using power pulse inversion can be used to predict contractile reserve early after myocardial infarction. METHODS AND RESULTS: We studied 19 stable patients 5.1(1.6) days after presentation using low dose dobutamine stress echocardiography and power pulse inversion using slow bolus intravenous injections of Optison. A 16-segment left ventricular model was used to define wall thickening at baseline and following low dose dobutamine infusion (1, normal; 2, reduced; 3, absent), and contrast opacification (1, homogeneous; 2, heterogenous or reduced; 3, absent). The techniques were compared on a segment-by-segment basis to determine whether microvascular integrity (contrast opacification score of 1 or 2) could predict contractile reserve (any improvement during low dose dobutamine infusion) in segments that were akinetic at rest. Follow-up echocardiography was performed one month later. RESULTS: Ninety-four (31%) of the 304 segments were akinetic at rest, and 22 (23%) of these demonstrated contractile reserve. In 87 (92%) of the resting akinetic segments contrast opacification could be adequately determined, and of these 20 (23%) showed microvascular integrity. The negative and positive predictive value of microvascular integrity for determining contractile reserve was 90% and 65%, respectively, and 92% and 59% respectively for predicting recovery of function. CONCLUSION: Power pulse inversion can be used at rest to determine myocardial function and simultaneously to predict contractile reserve of akinetic segments in patients early after myocardial infarction. This technique has the potential to provide a bedside assessment of myocardial viability.

Intravenous myocardial contrast echocardiography predicts recovery of dysynergic myocardium early after acute myocardial infarction.

OBJECTIVES: We aimed to ascertain whether triggered intravenous myocardial contrast echocardiography (MCE) can predict functional recovery in patients with acute myocardial infarction (AMI) and to determine the optimal triggering interval in this setting. BACKGROUND: Detection of myocardial viability early after AMI has both therapeutic and prognostic implications. Myocardial contrast echocardiography using intracoronary injections of contrast can detect viable myocardium, but there is little data on the use of recently developed intravenous MCE techniques for this purpose. METHODS: Ninety-six patients with recent AMI (4.8 +/- 1.7 days) underwent echocardiography at baseline and six months later or three months after revascularization to determine regional function (score 1 = normal to 3 = akinetic). Myocardial contrast echocardiography was performed at baseline using intravenous injections of Optison. Triggering intervals of 1:1 (early) and 1:10 (delayed) cardiac cycles were used. Segments were deemed viable if they demonstrated homogeneous contrast opacification. RESULTS: Of 400 akinetic segments at baseline, 109 (27%) improved during the follow-up period, and 375 (94%) were adequately visualized with MCE, of which 59 (16%) were homogeneously opacified by early and 125 (33%) by delayed MCE (negative predictive value for recovery of contractile function 74% and 84%, positive predictive value 29% and 47%, respectively). Independent predictors of functional recovery were delayed MCE (odds ratio [OR]: 4.0, p < 0.001), revascularization (OR: 6.0, p < 0.001), and log creatine kinase (OR: 0.5, p = 0.03). However, the presence or absence of >90% stenosis of the infarct-related artery did not influence the ability of triggered MCE to predict functional recovery. CONCLUSIONS: Intravenous delayed triggered MCE can independently detect myocardial viability early after AMI.

Apical hypertrophic cardiomyopathy: bedside diagnosis by intravenous contrast echocardiography.

Apical cardiomyopathy is rare in the West. The characteristic appearance on left ventriculography has been used to confirm the diagnosis of this condition; transthoracic echocardiography can also be useful in this regard. However, apical artifacts may obscure the typical appearance during echocardiography, and although the advent of tissue harmonic echocardiography has resulted in improved image quality, the technique still may be inadequate in the establishment of a diagnosis. We hypothesized that contrast echocardiography, which improves endocardial border delineation, may be the technique of choice for the diagnosis of apical hypertrophic cardiomyopathy. We report the case of a 40-year-old woman with Down syndrome who had chest pain. The electrocardiogram showed T-wave changes in the lateral precordial leads, but cardiac enzymes were normal. Tissue harmonic echocardiography showed apical akinesia. Intravenous contrast echocardiography, however, revealed typical features of hypertrophic apical cardiomyopathy. Thus contrast echocardiography may be used to establish the diagnosis of this condition.

Tissue harmonic imaging: a new method for predicting left ventricular thrombus?

We report a case of spontaneous echocardiographic contrast in the left ventricle visualized by transthoracic second harmonic imaging, but not by fundamental imaging, and subsequent thrombus formation.

Can nuclear cardiology really help in the emergency departments of the 21st century?

The cardiac troponins are a highly sensitive and specific marker for myocardial damage and have been shown to be useful in the management of patients with acute coronary syndromes. However, some patients with significant ischaemia have no myocardial damage, and therefore negative troponins, despite high risk of subsequent events. Furthermore as a result of the time delay before the troponins can be measured in the peripheral blood, serial sampling is required to rule out myocardial damage. Nuclear perfusion imaging provides an instantaneous assessment of perfusion at the time of injection which is not dependent of on myocardial necrosis, but the presence of flow heterogeneity. Thus these two techniques provide complementary information for the assessment of patients with chest pain and non-diagnostic electrocardiograms, and early perfusion imaging offers the possibility of more rapid assessment and decision making than is possible with troponins.