Resting Myocardial Contrast Echocardiography for the Evaluation of Coronary Microcirculation Dysfunction in Patients With Early Coronary Artery Disease

Value of Myocardial Contrast Echocardiography in Detecting Coronary Microcirculatory Dysfunction in Ischemia With Non-obstructive Coronary Artery Disease

OBJECTIVE

The aim of this study was to evaluate the value of myocardial contrast echocardiography (MCE) in detecting coronary microcirculation function dysfunction in ischemia with non-obstructive coronary artery (INOCA) disease.

METHODS

Twenty-one patients with a clinical diagnosis of INOCA were admitted to the First Affiliated Hospital of Xinjiang Medical University because of chest pain. All participants underwent MCE and [¹⁸F]fluorodeoxyglucose (FDG) positron emission tomography/computed tomography myocardial metabolic imaging. With the results of FDG PET taken as the gold standard, all myocardial segments were divided into a normal control group and a coronary artery microcirculation dysfunction (CMCD) group. We used MCE to measure myocardial perfusion parameters, including the ascending slope (β), time to peak (TTP), A and A × β. The receiver operating characteristic (ROC) curves of β, TTP, A and A × β were calculated to evaluate the diagnostic value of MCE for CMCD.

RESULTS

A total of 122 and 218 segments were investigated in the CMCD and control groups, respectively. On the basis of the statistical analysis of the MCE parameters of the two groups, the myocardial perfusion parameters β, A and A × β of all segments in the CMCD group decreased, and the TTP in the basal segment of the CMCD group was longer than that of the normal control group (all p values <0.05). On the basis of analysis of the ROC curve, β had the highest diagnostic efficiency in the middle segment.

CONCLUSION

This study found that MCE is valuable in the diagnosis of non-obstructive coronary artery complicated by CMCD.

Prognostic value of myocardial contrast echocardiography in acute anterior wall ST-segment elevation myocardial infarction with successful epicardial recanalization

Although myocardial contrast echocardiography (MCE) can evaluate microvascular perfusion abnormalities, its prognostic value is uncertain in acute anterior wall ST-Segment elevation myocardial infarction (STEMI) with successful epicardial recanalization. Therefore, the study aims to investigate the prognostic role of qualitative and quantitative MCE in acute anterior wall STEMI with successful epicardial recanalization. 153 STEMI patients were assessed by MCE within 7 days after successful epicardial recanalization. Qualitative perfusion parameters (microvascular perfusion score index, MPSI) and quantitative perfusion parameters (A, β, and Aβ) were acquired using a 17-segment model. And corrected A and Aβ were calculated. Patients were all followed for major adverse cardiovascular events (MACEs). During median follow-up of 27 (4) months, 39 (25.49%) patients experienced MACEs, while 114 (74.51%) were free from MACEs. Patients with MACEs had higher MPSI (1.65 ± 0.13 vs. No-MACEs 1.35 ± 0.20, P < 0.001), lower β (1.09 ± 0.19 s-1 vs. No-MACEs 1.34 ± 0.30 s-1, P < 0.001), corrected A (0.17 ± 0.03 dB vs. No-MACEs 0.19 ± 0.04 dB, P = 0.039) and lower corrected Aβ (0.19 ± 0.06 dB/s vs. No-MACEs 0.25 ± 0.08 dB/s, P < 0.001). MPSI of 1.44 provided an area under the curve (AUC) of 0.872, while β of 1.18 s-1 and corrected Aβ of 0.22 dB/s provided AUCs of 0.759 and 0.724, respectively. The combination of MPSI, β and corrected Aβ provided an increased AUC of 0.964 (all P < 0.05). Time-dependent ROC analysis showed that the AUCs of the MPSI, β, corrected Aβ and the combination at 1, 1.5 and 2 years indicated a strong predictive power for MACEs (AUC = 0.900/0.894/0.881 for MPSI, 0.648/0.704/0.732 for β, 0.674/0.686/0.722 for corrected Aβ, and 0.947/0.962/0.967 for the combination, respectively). Patients with MPSI < 1.44, β > 1.18 s-1, or corrected Aβ > 0.22 dB/s had lower event rate (all Log Rank P ≤ 0.001). MPSI, β, corrected Aβ, GLS and WBC were independent predictors of MACEs with adjusted hazard ratio of 34.41 (8.18-144.87), P < 0.001 for MPSI; 39.29 (27.46-65.44), P < 0.001 for β; 8.93 (1.46-54.55), P = 0.018 for corrected Aβ; 10.88 (2.83-41.86), P = 0.001 for GLS; and 1.43 (1.16-1.75), P = 0.001 for WBC. Qualitative and quantitative MCE can accurately predict MACEs in acute anterior wall STEMI with successful epicardial recanalization, and their combined predictive value is higher.

Prognostic value of resting myocardial contrast echocardiography: a meta-analysis

BACKGROUND

Resting myocardial perfusion (MP) and wall motion (WM) imaging during real time myocardial contrast echocardiography (MCE) improves the detection of coronary artery disease (CAD). However, its prognostic role in different clinical settings (emergency department and outpatient setting) remains unclear.

METHODS

A systematic search in PubMed and Embase databases, and the Cochrane library, was conducted to evaluate the role of resting MP and WM in predicting major adverse cardiac events (MACE), including death, nonfatal myocardial infarction (NFMI) and urgent revascularization in patients presenting to either outpatient clinics or emergency departments with suspected symptomatic CAD. Summary receiver operating characteristic (SROC) curves, sensitivity and specificity plots were applied to assess diagnostic performance using RevMan 5.3.

RESULTS

Seven studies met criteria, including 3668 patients (six with follow up ranging from two days to 2.6 years). The relative risk (RR) for predicting MACE in patients with both abnormal resting MP and WM was 6.1 (95% CI, 5.1-7.2) and 14.3 (95% CI, 10.3-19.8) for death/NFMI, when compared to normal resting MP and WM patients. Having both abnormal resting MP and WM was also more predictive of MACE (RR 1.7; 95% CI 1.5-1.9) and death/NFMI (RR, 2.2; 95% CI, 1.8-2.7) when compared to abnormal WM with normal resting MP.

CONCLUSION

In this meta-analysis of both ED and outpatient clinic presentations for suspected CAD, having both a resting regional MP and WM abnormality identifies the highest risk patient for adverse events.

Interleukin 8 targeted contrast echocardiography is effective to evaluate myocardial ischemia-reperfusion injury in the rabbits

Interleukin 8 (IL-8) is an important pro-inflammatory cytokine that recruits neutrophil to the areas of inflammation and has been implicated in myocardial ischemia reperfusion injury (MIRI). This study aimed to apply IL-8 targeted myocardial contrast echocardiography (MCE) to evaluate MIRI in rabbits. MCE imaging with IL-8 targeted microbubbles (MB_IL-8) and control microbubbles (MB_c) was performed in 40 Japanese white rabbits after brief proximal left anterior descending (LAD) partial occlusion for 30 min and subsequent reperfusion for 30 min, 60 min, 120 min and 180 min. Electrocardiogram and regional wall motion were assessed during occlusion and reperfusion. MCE demonstrated that IL-8 level rapidly increased in reperfused myocardial tissue and reached the peak after 120 min of reperfusion and lasted to 180 min of reperfusion. ELISA showed that the tendency of MCE data to change with reperfusion time was the same as that of IL-8 content. Taken together, these results suggest that targeted MCE with IL-8 antibody provides a new approach to noninvasive evaluation of MIRI using ultrasound imaging techniques.

Contrast Transthoracic Echocardiography Using 50% Glucose as a Contrast Agent for Screening of a Patent Foramen Ovale

A patent foramen ovale (PFO) is considered a risk factor for neurologic events. The goal of the study described here was to assess the feasibility, advantages, diagnostic sensitivity and accuracy of contrast transthoracic echocardiography examination (cTTE) using 50% glucose as a contrast agent in comparison with the use of agitated saline as contrast to screen for PFO. In our study, we found that the peak time, effective duration and duration of microbubbles produced by 50% glucose were all longer than those produced by the physiologic saline. The sensitivities for detection of PFO with cTTE using physiologic saline and 50% glucose as contrast were 83% (20/24) and 100% (24/24), respectively. TEE suggested a PFO in 24 patients in two groups. Use of 50% glucose as a contrast agent in cTTE examination enables ultrasound technicians to easily observe the right-to-left shunt across the PFO. However, the sensitivities for detection of PFO with cTTE using 50% glucose did not statistically significantly differ from those for physiologic saline.

The value of real-time myocardial contrast echocardiography for detecting coronary microcirculation function in coronary artery disease patients

Objective:

The aim of this study was to evaluate the value of real-time myocardial contrast echocardiography (RT-MCE) for detecting coronary microcirculation (CM) function in coronary artery disease (CAD) patients.

Methods:

Sixty-five consecutive patients were divided into CAD (n=52) and no-CAD (n=13) groups using coronary angiography (CAG). All patients underwent RT-MCE at rest and CAG within 1 week after RT-MCE. The ventricular segments in CAD patients were divided semi-quantitatively into ischemic and non-ischemic myocardial groups based on RT-MCE images. Myocardial blood volume (A), myocardial blood flow velocity (β), and mean myocardial blood flow (A×β) were obtained. The Gensini scores were calculated for CAD patients. The receiver operating characteristic (ROC) curve areas of A, β, and A×β were calculated to assess CM function in CAD patients.

Results:

A total of 798 and 204 segments were investigated in the CAD and non-CAD groups, respectively. In CAD patients, 332 ischemic and 466 non-ischemic segments were identified. The values of A, β, and A×β were significantly different among non-CAD, CAD, ischemic, and non-ischemic groups. ROC curve areas of A, β, and A×β were 0.85, 0.79, and 0.83, respectively, and significant differences were observed in these values among three Gensini score groups of the CAD patients.

Conclusion:

Varying degrees of CM function deterioration was observed in CAD patients both in ischemic and non-ischemic areas, with the deterioration being more sever in the former.

Contrast-Enhanced Ultrasound Imaging in Detection of Changes in Cerebral Perfusion

Contrast-enhanced ultrasonography (CEU) is a non-invasive imaging technique that provides real-time, bedside information on changes in global and segmental organ perfusion. Currently, there is a lack of data concerning changes in the distribution of segmental brain perfusion in acute ischemic stroke treated by decompressive craniectomy. The aim of our case series was to assess the role of CEU after decompressive craniectomy in patients with acute ischemic stroke. CEU was performed in 12 patients at baseline and after any one of the following interventions was performed as dictated by the patient's clinical condition: vasoactive drug administration (in order to achieve cerebral perfusion pressure ≥70 mm Hg and mean arterial pressure <100 mm Hg for management of arterial blood pressure) and mild hyperventilation (carbon dioxide arterial pressure = 30-35 mm Hg). CEU was able to detect a significant variation in cerebral contrast distribution in both normal and pathologic hemispheres after induced hyperventilation (difference in time to peak [dTTP] = -38.4%), vasodilation (dTTP = -6.6%) and vasoconstriction (dTTP = +31.2%) (p < 0.05). CEU can be useful in assessing real-time cerebral perfusion changes in neurocritical care patients.