DOWNLOAD PDF MYOCARDIAL CONTRAST TWO DIMENSIONAL ECHOCARDIOGRAPHY (DEVELOPMENTS IN CARDIOVASCULAR MEDICINE)

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1 Chapter 1 : Imaging Cardiovascular Medicine Stanford Medicine contrast two-dimensional echocardiography (MC-2DE), a new and exciting diagnostic methodology for assessment of myocardial perfusion, which has seen rapid development and has now entered the clinical stage. Left ventricular ejection fraction can be measured by a variety of invasive and non-invasive cardiac techniques. This study assesses the relation of three diagnostic modalities to each other in the measurement of left ventricular ejection fraction: Retrospective chart review was conducted on 58 patients hospitalized with chest pain, who underwent left ventricular ejection fraction evaluation using each of the aforementioned modalities within a 3-month period not interrupted by myocardial infarction or revascularization. The mean left ventricular ejection fraction values were as follows: Correlations coefficients and associated p values were as follows: Our results indicate that strong positive correlations exist among the three techniques studied. Cardiovascular, radiology, left ventricular ejection fraction, quantitative gated single-photon emission computed tomography, echocardiography, contrast left ventriculography Introduction Left ventricular LV ejection fraction LVEF is an ejection phase index that is commonly used in the diagnosis and management of cardiovascular disease. In patients undergoing left heart catheterization with coronary angiography, ICLV exposes patients to additional radiation and to the risk of contrast-induced acute kidney injury. Methods Patient selection Patients hospitalized at the Harry S. Dyslipidemia was defined as elevated low-density lipoprotein or low levels of high-density lipoprotein cholesterol. Cerebrovascular disease was defined as ischemic stroke or transient ischemic attacks. Patients without chest pain and those who suffered from acute myocardial infarction or who underwent percutaneous coronary intervention or coronary artery bypass grafting prior to assessment of LVEF with all three diagnostic techniques were excluded from the study, as were subjects with technically inadequate studies of LVEF. LV end-diastolic and end-systolic volumes were measured using the method of Sandler and Dodge. The normal range for LVEF in our laboratory is 0. All images were obtained by a single-skilled cardiac sonographer. Images were corrected for attenuation using a transmission source of Gadolinium Tc99m was the radiopharmaceutical used to determine baseline LVEF in each patient. LVEF for each technique was measured by a single experienced cardiologist or nuclear medicine physician. Each individual was blinded to the measurements obtained from the other techniques. This research was approved by the Institutional Review Board of the University of Missouri-Columbia in accordance with the principles of the Declaration of Helsinki approval number: Linear regression analysis using Pearson correlation coefficients was used to compare LVEF values as follows: Results Patient characteristics A total of patients were evaluated for chest pain. A total of 72 patients had all three techniques performed within 3 months of each other. Of these, 58 had no myocardial infarction or revascularization procedure before completion of LVEF analysis with all three modalities. Baseline demographic and clinical characteristics of the 58 patients entered into the study are summarized in Table 1. Page 1

2 Chapter 2 : Contrast Echocardiography To our knowledge, this is the first book dealing exclusively with myocardial contrast two-dimensional echocardiography (MC-2DE), a new and exciting diagnostic methodology for assessment of myocardial perfusion, which has seen rapid development and has now entered the clinical stage. After contrast, the percent of uninterpretable studies decreased from A significant impact on management was observed: J Am Coll Cardiol. This study was the first to prove the value of MCE in identifying aetiology ischaemic vs non-ischaemic in patients presenting for the first time with heart failure. This was the first study to show that perfusion assessment has incremental benefit over wall motion analysis in detecting CAD. The first paper to show that delayed imaging 1: MCE was performed at baseline using triggering intervals of 1: Delayed imaging had superior positive and negative predictive value for recovery of systolic function. The authors concluded that delayed triggered MCE can independently detect myocardial viability early after AMI and that delayed triggered imaging is superior to early triggered imaging. J Am Coll Cardiol ; 38 1: Landmark study which proved, for the first time, that capillaries play a crucial role in regulation of coronary blood flow CBF. A canine model of the coronary circulation with three compartments was created arterial, capillary, venous. In the presence of a non-critical stenosis, total myocardial vascular resistance increased during hyperaemia predominantly due to increased capillary resistance. Thus, contrary to widely held beliefs at that time, capillaries were shown to participate in CBF regulation. Landmark study that provided proof for the physiological basis of quantification of MCE by studying bubble and ultrasound interaction. Myocardial blood flow MBF studied in ex-vivo and in-vivo experimental models in 21 dogs. It was shown that collateral-derived residual flow is common in such patients and that it can maintain viability for several weeks. Moreover, the degree of improvement of regional function after revascularisation was related to the percentage of the occluded bed perfused by collateral flow. The authors concluded that viability appears to be directly associated with the presence of collateral blood flow within the infarct bed. N Engl J Med ; The first study in man using Albunex â sonicated albumin â contrast agent. J Am Coll Cardiol ; 16 2: J Am Coll Cardiol ;3 1: They concluded that contrast is a safe and useful diagnostic tool in the stress echocardiography laboratory. In a unique randomised trial setting, patients referred for DSE agreed to have the test twice within a 24hour period â once with contrast and once without. The authors concluded that during dobutamine echocardiography, contrast agent administration improves endocardial visualization at rest and more so during stress, leading to a higher confidence of interpretation and greater accuracy in evaluating CAD. Accuracy to detect regional abnormalities, as defined by an expert panel, was highest for contrast echocardiography. Unenhanced echocardiography underestimated ejection fraction EF and had only moderate correlation with CMR and ventriculography. The inter-observer variability measured by intra-class coefficient was highest for contrast echo 0. A Norwegian prospective study in which patients underwent unenhanced 2D echocardiography, contrast-enhanced 2D-echo and cardiac MRI 1. EF and LV volumes were significantly underestimated by unenhanced echo and accuracy of all parameters were significantly improved by use of contrast, including inter-observer and intra-observer variability. This is the first study to demonstrate the incremental benefit of myocardial perfusion assessment in this acute patient population. Abnormal MCE was the single best predictor of adverse cardiac events, both hard events and a composite end-point including hospitalisation for recurrent angina. The inclusion of MCE results significantly improved the multivariate model, even with inclusion of wall motion data. J Am Coll Cardiol ;47 1: This key paper involved a retrospective analysis of patients who had undergone MCE during stress echocardiography with dobutamine. For the first time, incremental prognostic value over clinical variables and, crucially, wall motion was proven â patients with normal perfusion had better outcomes median follow-up period 20months than those with Page 2

3 normal wall motion. Quantitative MCE was performed up to 4 weeks prior to coronary angiography. MCE-derived coronary flow reserve was significantly different between each of the four groups and accurately predicted severity of disease. Am J Cardiol ;93 9: A linear relation was found between flow velocity reserve determined using the 2 methods and the authors concluded that coronary flow reserve can be measured in humans using MCE. The extent of residual myocardial viability by MCE independently predicted hard end-points of cardiac death and repeat MI. Contractile reserve was assessed with low-dose dobutamine 12 weeks following revascularization. Am Heart J ; 2: Repeat echocardiography was performed at months. Quantitative MCE parameters were significantly different between dysfunctional segments that recovered function hibernating versus those which remained dysfunctional. MCE had similar senstitity to thallium scanning and superior specificity for predicting functional recovery on a segmental level. In this study, 20 patients underwent triggered MCE during continuous contrast infusion 24hrs prior to myocardial biopsy at time of CABG surgery. Quantitative parameters correlated closely with microvascular and capillary density and inversely correlated with collagen content i. The study showed that microvascular integrity is directly related to MCE parameters and that these parameters can predict functional recovery following revascularisation. Page 3

4 Chapter 3 : Roll Prevention Myocardial For Sale - Vintage Glass Bottles Intravenous myocardial contrast echocardiography AMI is a sign of the development of heart failure and carries a dyssynergy of the LV on two dimensional. Advanced Search Abstract Two-dimensional echocardiography has historically played a limited role in the diagnosis of acute myocarditis because of a lack of specific diagnostic features. The emergence of novel echocardiographic modalities such as strain and myocardial perfusion imaging have greatly augmented the scope of echocardiography, permitting the assessment of myocardial contractility, blood flow, and microvascular integrity. However, the application of these cutting-edge techniques in the diagnosis of acute myocarditis is still at a nascent stage. These findings and the final diagnosis were later confirmed by cardiac magnetic resonance imaging. This case highlights the potential utility of novel echocardiographic techniques in the diagnostic workup of acute myocarditis and underscores the need for prospective studies to assess the sensitivity and specificity of these newer technologies. To our knowledge, this is the first report of a multimodality echocardiographic approach towards the diagnosis of myocarditis. Two-dimensional strain imaging, Speckle tracking, Myocardial perfusion echocardiography Introduction Myocarditis presents in myriad ways, often mimicking acute coronary syndrome on initial presentation. Conventional two-dimensional 2D echocardiography has traditionally played a limited role in the diagnostic armamentarium for acute myocarditis. We present a case of acute myocarditis wherein a multimodality echocardiographic approach was adopted. Two-dimensional echocardiographic strain 2D strain imaging and myocardial contrast echocardiography were performed as part of the initial diagnostic workup, and findings later confirmed with cardiac magnetic resonance CMR imaging. Case report This is the case of a previously healthy year-old male with a recent viral prodrome who presented to the emergency department with chest pain for 3 days. The pain was precordial, stabbing in nature, and partially relieved by leaning forward. A review of his previous records did not reveal any significant past medical, surgical, or family history. Our patient was a non-smoker and denied history of substance abuse. The physical examination revealed a pericardial rub, but no other significant abnormalities. Laboratory values showed a WBC count of The pleuritic chest pain, the pericardial rub, diffuse ST and T wave changes and elevated cardiac troponins in a young previously healthy individual with a recent viral prodrome suggested a working diagnosis of myopericarditis, and an infectious workup to identify the disease aetiology was initiated. Serological testing revealed elevated Coxsackie A9 titres at 1: An ANA titre was negative. Hyperacute T waves are seen in leads V2 and V3. Significantly attenuated longitudinal strain in the inferior-apical segments yellow: Corresponding circumferential strain of the same image shows paradoxical circumferential strain in the inferolateral segment crimson tracing and marked reduction of peak strain in the inferior and lateral segments. Time intensity curves were sampled offline regions of interest of 6. Real-time myocardial contrast echocardiography revealed attenuated perfusion with delayed contrast replenishment see wash-in time intensity curves in the above-referenced segments compared with adjacent unaffected segments. When viewed in entirety, data were highly suggestive of myocarditis, with the most severe involvement apparent in the inferolateral segments. Fitted replenishment curves for corresponding areas show attenuated plateau contrast levels and late contrast plateauing in all regions other than the septum preserved perfusion. Findings suggest disruption of microvasculature in the inferolateral and apical segments. The abnormalities detected on echocardiography were later confirmed by gadolinium-enhanced CMR using a 1. B Short-axis delayed enhanced imaging demonstrating extensive enhancement of mid-wall and epicardium with sparing of the subendocardium. Chapter 4 : Myocardial Viability: Comparison With Other Techniques Clinical Gate Page 4

5 To our knowledge, this is the first book dealing exclusively with myocardial contrast two-dimensional echocardiography (MC-2DE), a new and exciting diagnostic methodology for assessment of myocardial. Page 5