Clinical application of quantitative analysis in real-time MCE

Abstract

The introduction of stable microbubble contrast agents and technological advances have recently made it feasible to perform quantitative measurements of microvascular damage by myocardial contrast echocardiography (MCE). Qontrast is a new software system far such measurements. It includes physiological filters, global rescale, regional rescale, automatic myocardial tracking, manual ECG trigger and parametric imaging. Qontrast was tested on 5 pigs given sulphur hexafluoride bubbles (I ml/min) and fluorescent microspheres (reference) after the induction of 50% and 100% stenosis of left anterior descending coronary artery. The image sequences were repeated four times using different ultrasound (US) equipment. A close correlation was found between the ratio risk area/control area by microspheres and the equivalent ratio risk area/control area (Sl x beta) by MCE, being approximately 0.9 far any contrast modality tested. Parametric MCE and SPELT were compared in 12 patients with recent myocardial infarction, including 119 segments. Agreement amounted to 83% (kappa: 0.53 far peak SI and 0.55 far SI x beta). The sensitivity and specificity of peak SI far detecting abnormal segmental tracer uptake were 67% and 88%; the values far Sl x beta were 70% and 87%. Parametric MCE is a promising imaging technique far the assessment of myocardial perfusion in patients with suspected or known coronary artery disease.

Real‐time perfusion adenosine stress echocardiography versus myocardial perfusion adenosine scintigraphy for the detection of myocardial ischaemia in patients with stable coronary artery disease

“…These tools have been tested in animal models (Agati et al 2004;Lafitte et al 2002) and are currently undergoing testing in healthy subjects as well as in patients (Bekeredjian et al 2003;Korosoglou et al 2004;Peltier et al 2004). …”

The Extent of Microvascular Damage During Myocardial Contrast Echocardiography Is Superior to Other Known Indexes of Post-Infarct Reperfusion in Predicting Left Ventricular Remodeling

“…Myocardial opacification at MCE, the echocardiographic parameter of MD, was visually assessed in each myocardial segment and semiquantitatively scored. Single perfusion score was assigned based on both the change in myocardial signal intensity throughout the replenishment curve and the degree of opacification at the peak contrast effect (11). Scores were graded as 1 ϭ normal (homogeneous opacification approximating that of the normal region at peak and normal rate of increase in signal); 2 ϭ reduced (partial or reduced opacification compared with the normal region at peak or reduced rate of increase in signal intensity); and 3 ϭ absent (no opacification throughout replenishment time).…”

“…A contrast score index (CSI) was calculated by the sum of MCE score in each segment divided by the total number of segments. Endocardial length of transmural contrast defect (CD) (score ϭ 3) and of WM abnormality was calculated in each apical view, averaged and expressed as percentage of LV endocardial length, as previously described (10,11). Two experienced observers who had no knowledge of the patient identity or conventional echocardiographic data performed the MCE data analysis.…”

Methods to investigate coronary microvascular function in clinical practice

“…Investigating coronary microvascular function Lanza et al 7 49 59 MI Perfusion defect Standard echo Ballcells et al 50 30 MI Risk area/no-reflow Dobutamine stress echo Galiuto et al 51 24 MI No-reflow Standard echo Bolognese et al 52 124 MI No-reflow Standard echo Agati et al 53 12 MI No-reflow SPECT Janardhanan et al 54 42 MI No-reflow CMR Moir et al 55 90 CAD Stress perfusion defect Coronary angiography Galiuto et al 56 50 MI No-reflow Standard echo Trindade et al 57 20 MI No-reflow CMR Galiuto et al 58 110 MI No-reflow Coronary angiography Abdelmoneim et al 59 2 HM Vascularity Standard echo Hayat et al 60 83 CAD Stress perfusion defect SPECT Senior et al 61 662 CAD Stress perfusion defect SPECT Mansencal et al 62 31 HM Vascularity Histopathology Galiuto et al 63 20 Takotsubo Perfusion defects Standard echo CAD, stable coronary artery disease; CMR, cardiac magnetic resonance; HM, heart masses; MI, myocardial infarction; SPECT, single-photon emission tomography. tomography (MIBI-SPECT), 69 in detecting and quantifying the extent of no-reflow.…”