11 research outputs found
Temporal evolution of myocardial hemorrhage and edema in patients after acute st-segment elevation myocardial infarction:Pathophysiological insights and clinical implications
Background The time course and relationships of myocardial hemorrhage and edema in patients after acute STâsegment elevation myocardial infarction (STEMI) are uncertain.
Methods and Results Patients with STâsegment elevation myocardial infarction treated by primary percutaneous coronary intervention underwent cardiac magnetic resonance imaging on 4 occasions: at 4 to 12Â hours, 3Â days, 10Â days, and 7Â months after reperfusion. Myocardial edema (native T2) and hemorrhage (T2*) were measured in regions of interest in remote and injured myocardium. Myocardial hemorrhage was taken to represent a hypointense infarct core with a T2* value <20Â ms. Thirty patients with STâsegment elevation myocardial infarction (mean age 54Â years; 25 [83%] male) gave informed consent. Myocardial hemorrhage occurred in 7 (23%), 13 (43%), 11 (33%), and 4 (13%) patients at 4 to 12Â hours, 3Â days, 10Â days, and 7Â months, respectively, consistent with a unimodal pattern. The corresponding median amounts of myocardial hemorrhage (percentage of left ventricular mass) during the first 10Â days after myocardial infarction were 2.7% (interquartile range [IQR] 0.0â5.6%), 7.0% (IQR 4.9â7.5%), and 4.1% (IQR 2.6â5.5%; P<0.001). Similar unimodal temporal patterns were observed for myocardial edema (percentage of left ventricular mass) in all patients (P=0.001) and for infarct zone edema (T2, in ms: 62.1 [SD 2.9], 64.4 [SD 4.9], 65.9 [SD 5.3]; P<0.001) in patients without myocardial hemorrhage. Alternatively, in patients with myocardial hemorrhage, infarct zone edema was reduced at day 3 (T2, in ms: 51.8 [SD 4.6]; P<0.001), depicting a bimodal pattern. Left ventricular endâdiastolic volume increased from baseline to 7Â months in patients with myocardial hemorrhage (P=0.001) but not in patients without hemorrhage (P=0.377).
Conclusions The temporal evolutions of myocardial hemorrhage and edema are unimodal, whereas infarct zone edema (T2 value) has a bimodal pattern. Myocardial hemorrhage is prognostically important and represents a target for therapeutic interventions that are designed to preserve vascular integrity following coronary reperfusion
Predictors of segmental myocardial functional recovery in patients after an acute ST-elevation myocardial infarction
Objective:
We hypothesized that Displacement Encoding with Stimulated Echoes (DENSE) and feature-tracking derived circumferential strain would provide incremental prognostic value over the extent of infarction for recovery of segmental myocardial function.
Methods:
Two hundred and sixty-one patients (mean age 59 years, 73% male) underwent MRI 2 days post-ST elevation myocardial infarction (STEMI) and 241 (92%) underwent repeat imaging 6 months later.
The MRI protocol included cine, 2D-cine DENSE, T2 mapping and late enhancement.
Wall motion scoring was assessed by 2-blinded observers and adjudicated by a third. (WMS: 1=normal, 2=hypokinetic, 3=akinetic, 4=dyskinetic). WMS improvement was defined as a decrease in WMSââ„â1, and normalization where WMSâ=â1 on follow-up. Segmental circumferential strain was derived utilizing DENSE and feature-tracking.
A generalized linear mixed model with random effect of subject was constructed and used to account for repeated sampling when investigating predictors of segmental myocardial improvement or normalization
Results:
At baseline and follow-up, 1416 segments had evaluable data for all parameters. Circumferential strain by DENSE (pâ<â0.001) and feature-tracking (pâ<â0.001), extent of oedema (pâ<â0.001), infarct size (pâ<â0.001), and microvascular obstruction (pâ<â0.001) were associates of both improvement and normalization of WMS. Circumferential strain provided incremental predictive value even after accounting for infarct size, extent of oedema and microvascular obstruction, for segmental improvement (DENSE: odds ratio, 95% confidence intervals: 1.08 per â1% peak strain, 1.05â1.12, pâ<â0.001, feature-tracking: odds ratio, 95% confidence intervals: 1.05 per â1% peak strain, 1.03â1.07, pâ<â0.001) and segmental normalization (DENSE: 1.08 per â1% peak strain, 1.04â1.12, pâ<â0.001, feature-tracking: 1.06 per â1% peak strain, 1.04â1.08, pâ<â0.001).
Conclusions:
Circumferential strain provides incremental prognostic value over segmental infarct size in patients post STEMI for predicting segmental improvement or normalization by wall-motion scoring
Implications of serial measurements of natriuretic peptides in heart failure: insights from BIOSTATâCHF
No abstract available
Multimodal quantification and validation of 3D regional myocardial function
International audienceThe aim of this project is to design a generic formalism for parietal and regional tracking of the left ventricle (LV) and to adapt it to 3D+t3D+t cardiac imaging modalities used in clinical routine (echocardiography, gated-SPECT, cine-MRI). The estimated displacement field must be reliable enough and insensitive to various artifacts to assess regional myocardial function in 3D from the accurate and precise computation of strain. The strain has recently proved to be of great interest for diagnosis and prognostic in cardiology, but its interpretation remains difficult because of the relative nature of the indices. The clinical objective of the 3DStrain project is to bring answers about the knowledge of normality
Incidence of procedural myocardial infarction and cardiac magnetic resonance imaging-detected myocardial injury following percutaneous coronary intervention with rotational atherectomy
No abstract available