Patterns of myocardial perfusion in humans evaluated with contrast-enhanced 320 multidetector computed tomography

Left ventricular (LV) myocardial contrast enhancement can be recorded using 320 multi detector computed tomography (MDCT). We aimed to (1) assess patterns of regional myocardial perfusion at rest and compare them with NH(3) positron emission tomography (PET) (2) and to assess the effect of intravenous adenosine infusion on regional myocardial perfusion. To evaluate myocardial perfusion patterns at rest, we scanned 14 healthy subjects with PET and 14 age and gender matched subjects with 320 MDCT. To evaluate the effect of adenosine stress on relative perfusion patterns 14 subjects with near-normal epicardial coronary arteries were studied at rest and during adenosine stress. Relative perfusion was assessed as attenuation density (AD) in 16 segments of the LV, and each segment was divided into 3 layers: endo-, mid- and epi-cardial. During rest the relative AD by MDCT was lower in the lateral wall compared with the remainder of the LV (P?相似文献   

Optimal timing for first-pass stress CT myocardial perfusion imaging

CT-based myocardial perfusion imaging (CTP) has been shown to accurately detect myocardial perfusion defects when compared to SPECT. When performing single-phase first-pass stress CTP, timing is of major importance. The aim of this study was to provide guidance for optimal timing of single-phase first-pass stress CTP acquisitions. 16 patients (12 male, age, 69 ± 8 years) with known or suspected coronary artery disease underwent invasive coronary angiography with fractional flow reserve (FFR) measurements using a pressure wire as well as a time-resolved CTP protocol under adenosine stress, performed on a dual-Source CT scanner over a period of 30 s. From the CTP data, time-attenuation curves have been determined both in known ischemic myocardium with a corresponding coronary artery stenosis as proven by a FFR below 0.75 in invasive coronary angiography, as well as in non-ischemic reference myocardium during pharmacological stress. Furthermore, contrast enhancement in the ascending aorta was determined. The time point for an optimal contrast (i.e., difference in Hounsfield Units, HU) between ischemic and normal myocardium was determined. Under pharmacological stress using adenosine, a maximum mean HU difference between ischemic and non-ischemic myocardium (17.7–22.5 HU) was observed 24–32 s after injection of contrast medium. The maximal attenuation difference between normal and ischemic myocardium ranged from 15 to 77 HU in the analyzed patient cohort. When applying a bolus-tracking technique with an automatic contrast detection in the proximal ascending aorta, the optimal time frame for stress CTP was between 8 and 16 s after contrast enhancement in the aorta exceeds 100 HU, or between 7 and 15 s using a threshold of 150 HU. For first-pass CT myocardial perfusion imaging there is a time frame of approximately 8 s for optimal differentiation of ischemic and non-ischemic myocardium, which will be helpful to optimize single-phase CTP scans.     

Disagreement between splenic switch-off and myocardial T1-mapping after caffeine intake

Caffeine is an adenosine receptor antagonist and a possible cause of inadequate stress perfusion. Splenic switch-off (SSO) and splenic rest-stress T1-mapping have been proposed as indicators of stress adequacy during perfusion cardiac magnetic resonance (CMR). We compared myocardial rest-stress T1-mapping with SSO and splenic rest-stress T1-mapping in patients with and without recent coffee intake. We analyzed 344 consecutive patients suspected of myocardial ischemia with adenosine perfusion CMR. All 146 normal CMR studies with a normal T1-rest of the myocardium, used as standard of reference, were included and divided in two groups. 22 patients accidentally ingested coffee <?4 h before CMR, compared to control group of 124 patients without self-reported coffee intake. Two independent readers graded SSO visually. T1-reactivity (ΔT1) was defined as percentual difference in T1-rest and T1-stress. Follow-up data were extracted from electronic patients records. In patients with recent coffee intake SSO was identified in 96%, which showed no significant difference with SSO in controls (94%, p?=?0.835), however event rates were significantly different (13.6 and 0.8%, respectively (p?<?0.001), median FU 17 months). Myocardial ΔT1 in the coffee group (??5.2%) was significantly lower compared to control (+?4.0%, p?<?0.001), in contrast to the splenic ΔT1 (??3.7 and ??4.0%, p?=?0.789). The splenic T1-mapping results failed to predict false negative results. SSO and splenic rest-stress T1-mapping are not reliable indicators of stress adequacy in patients with recent coffee intake. Therefore, the dark spleen sign does not indicate adequate myocardial stress in patients with recent caffeine intake. Myocardial rest-stress T1-mapping is an excellent indicator of stress adequacy during adenosine perfusion CMR.     

320排动态容积CT心肌灌注成像诊断猪急性心肌缺血再灌注损伤的实验研究

目的 评价320排CT心肌灌注成像(CTP)是否可以准确诊断猪急性心肌缺血再灌注损伤引起的心肌灌注异常.方法 8只猪通过介入球囊栓塞左冠状动脉前降支(LAD)中远段30 min后再通90 min建立再灌注损伤模型,术后行CTP扫描.检查结束后立即处死动物,取出心脏,进行氯化三苯基四氮唑(TTC)染色,分析心肌缺血再灌注损伤范围,显微镜下观察病理学改变;以病理结果为参照,测量CTP左心室短轴位二维图中损伤区、非损伤区心肌的CT值.将左心室壁分为17个节段,确定二维图、心肌透壁灌注率(TPR)图和大体病理上心肌损伤的节段数.以病理结果为金标准分别评价二维图、TPR图两组图像显示心肌损伤节段的敏感性、特异性和一致性.利用配对t检验分析损伤区和非损伤心肌CT值的差异.结果 8只猪TPR图见心尖前壁、心尖间隔灌注稀疏甚至缺损,左心室短轴位二维图中再灌注损伤区较正常心肌呈明显低密度,损伤区心肌CT值[(56.23±8.68)HU]较正常心肌[(120.57±15.36)HU]明显降低(t=8.83,P<0.01).与病理金标准对照,TPR图诊断再灌注损伤的敏感性、特异性、阴性预测值和阳性预测值分别为89.3%(25/28)、93.5%(101/108)、78.1%(25/32)、97.1%(101/104),Kappa值为0.79;而二维图的敏感性、特异性、阴性预测值、阳性预测值和Kappa值分别为85.7%(24/28)、92.6%(100/108)、75.0%(24/32)、96.2%(100/104)和0.74.结论 320排CT心肌灌注成像可用于检测猪急性心肌缺血再灌注损伤,与病理诊断一致性好.     

Impact of surgical pulmonary valve replacement on ventricular mechanics in children with repaired tetralogy of Fallot

Impaired ventricular myocardial mechanics are observed in patients with repaired tetralogy of Fallot (rTOF). Effects of pulmonary valve replacement (PVR) on ventricular remodeling are controversial. The objective was to assess the impact of surgical PVR on ventricular mechanics in pediatric patients after rTOF. Speckle-tracking analysis was performed in 50 rTOF children, aged 12.6?±?3.3 years, pre-operatively and 14.5?±?2.2 months post-PVR. Early post-operative studies 2.2?±?0.6 months post-PVR were performed in 28 patients. Cardiac magnetic resonance (CMR) pre- and post-PVR was collected. Mid-term post-PVR right ventricular (RV) longitudinal strain increased above pre-operative strain (?19.2?±?2.7 to ?22.0?±?3.0%, p?<?0.001) with increases observed in individual RV segments. Left ventricular (LV) strain did not differ at medium-term follow-up. LV and RV longitudinal strain was reduced early post-operatively, followed by recovery of biventricular systolic strain by mid-term follow-up. CMR RV end-diastolic indexed volumes correlated with RV strain pre-operatively (r?=?0.432, p?=?0.005) and at mid-term follow-up (r?=?0.532, p?=?0.001). Volume-loaded RVs had reduced early RV basal longitudinal strain compared to pressure-loading conditions. Reversed basal counterclockwise rotation was associated with lower mid-term global LV and basal RV strain compared to patients with normal rotation. An increase in mid-term global and regional RV strain beyond pre-operative values suggests positive RV remodeling and adaptation occurs in children post-PVR. Patients with larger pre-operative RV volumes had lower RV strain post-operatively. The impact of LV rotation on RV mechanics highlights the presence of ventriculo-ventricular interactions. These findings have important clinical implications in pediatric rTOF patients towards identifying pre-operative factors that predict RV post-operative remodeling.     

Caffeine intake inverts the effect of adenosine on myocardial perfusion during stress as measured by T1 mapping

Caffeine intake before adenosine stress myocardial perfusion imaging may cause false negative findings. We hypothesized that the antagonistic effect of caffeine can be measured by T1 relaxation times in rest and adenosine stress cardiac magnetic resonance imaging (CMR), as T1 mapping techniques are sensitive to changes in myocardial blood volume. We prospectively analyzed 105 consecutive patients with adenosine stress perfusion CMR on a 1.5-T MRI system. Rest and stress T1 mapping was performed using Modified Look-Locker Inversion recovery. T1 reactivity was defined as difference in T1_rest and T1_stress (?T1). Fifteen patients drank coffee within 4 h of CMR (<4H caffeine group), and 10 patients had coffee the day before (>8H caffeine group). Comparison was made to patients without self-reported coffee intake: 50 with normal CMR (control group), 18 with myocardial ischemia, and 12 with myocardial infarction. The national review board approved the study; all patients gave written informed consent. The <4H caffeine group showed inverted ?T1 of ?7.8?% (T1_rest 975?±?42 ms, T1_stress 898?±?51 ms, p?<?0.0005). The >8H caffeine group showed reduced T1 reactivity (1.8?%; T1_rest 979 ms, T1_stress 997 ms) compared to the controls (4.3?%; T1_rest 977?±?40 ms, T1_stress 1018?±?40 ms), p?<?0.0005. Ischemic and infarcted myocardium showed minimal T1 reactivity (0.2 and 0.3?%, respectively). Caffeine intake inverts the adenosine effect during stress perfusion CMR as measured by T1 mapping. T1 reactivity can assess the adequacy of adenosine-induced stress in perfusion CMR.     

Temporal averaging for analysis of four-dimensional whole-heart computed tomography perfusion of the myocardium: proof-of-concept study

To assess the feasibility of four-dimensional (4D) whole-heart computed tomography perfusion (CTP) of the myocardium and the added value of temporal averaging of consecutive 3D datasets from different heartbeats for analysis. We included 30 patients with suspected or known coronary artery disease (CAD) who underwent 320-row coronary CT angiography (CTA) and myocardial CTP. Out of these, 15 patients underwent magnetic resonance myocardial perfusion imaging (MR MPI). All CTP examinations were initiated after 3 min of intravenous infusion of adenosine (140 µg/kg/min) and were performed dynamically covering the entire heart every heart beat over a period of 20?±?3 heart beats. Temporal averaging for dynamic CTP visualisation was analysed for the combination of two, three, four, six, and eight consecutive 3D datasets. Input time attenuation curves (TAC) were delivered from measurement points in the centre of the left ventricle. In all 30 patients, myocardial 4D CTP was feasible and temporal averaging was successfully implemented for all planned combinations of 3D datasets. Temporal averaging of three consecutive 3D datasets showed best performance in the analysis of all CTP image quality parameters: noise, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), subjective image quality, and diagnostic accuracy with an improvement of SNR and CNR by a factor of 2.2?±?1.3 and 1.3?±?0.9. With increasing level of temporal averaging, the input TACs became smoother, but also shorter. Out of the 11 perfusion defects detected with MR MPI, 9 defects were also visible on the 4D CTP images. Whole-heart CTP of the myocardium is feasible and temporal averaging of dynamic datasets improves quantitative image quality parameters and visualization of perfusion defects while further studies are needed to assess its added value for quantification of perfusion parameters.     

First-pass myocardial perfusion cardiovascular magnetic resonance at 3 Tesla.

PURPOSE: To test the feasibility of first-pass contrast-enhanced myocardial perfusion imaging at 3 Tesla and to evaluate the change in perfusion index between normal, remote and ischemic myocardium, we obtained perfusion index from healthy subjects and patients with coronary artery stenosis. MATERIALS AND METHODS: First-pass contrast-enhanced perfusion imaging was performed on 12 patients and 32 age-matched healthy subjects in both rest and dipyridamole-induced stress states. After bolus injection of contrast agent, Gd-DTPA with dose of 0.025 mmol/kg body weight and injection time of 1.5 s, three short-axis images from apex to base of the left ventricle (LV) were acquired for 80 cardiac cycles using saturation recovery turbo FLASH sequence. The maximal upslope (Upslope) was derived from the signal-time curves of the LV cavity and myocardium to measure myocardial perfusion. Within 72 hours after cardiovascular magnetic resonance examination, patients received coronary angiography, and the results were correlated with cardiovascular magnetic resonance results. RESULTS: Using our protocol of contrast agent administration, sufficient perfusion contrast was obtained without susceptibility-induced signal drop-out at the interface between LV cavity and the myocardium. In healthy volunteers, Upslope showed no dependence on myocardial segments or coronary territories. Upslope increased significantly from rest to stress in normal myocardium (0.09 +/- 0.03 vs. 0.16 +/- 0.05, p < 0.001) and remote myocardium (0.09 +/- 0.03 vs. 0.13 +/- 0.03, p < 0.001), whereas in ischemic myocardium the change was insignificant (0.11 +/- 0.03 vs. 0.10 +/- 0.04, p = ns). This resulted in significant difference in the ratio of Upslope at stress to that at rest, representing myocardial perfusion reserve, between ischemic and non-ischemic myocardium (0.96 +/- 0.41 vs. 1.71 +/- 0.42, p < 0.001 for ischemic vs. normal myocardium; 0.96 +/- 0.41 vs. 1.59 +/- 0.40, p < 0.001 for ischemic vs. remote myocardium). CONCLUSIONS: First-pass gadolinium-enhanced myocardial perfusion imaging at 3 Tesla is feasible. The Upslope ratio can differentiate ischemic from non-ischemic myocardium.     

Plaque characteristics and inflammatory markers for the prediction of major cardiovascular events in patients with ST-segment elevation myocardial infarction

To investigate the clinical utility of culprit plaque characteristics and inflammatory markers for the prediction of future cardiovascular events in patients with ST-segment elevation myocardial infarction (STEMI) with successful drug-eluting stent (DES) implantation. We evaluated 172 STEMI patients with successful primary percutaneous coronary intervention (PCI) with DES using pre-PCI high-sensitivity C-reactive protein (hs-CRP), neutrophil-to-lymphocyte ratio (NLR) and pre-PCI intravascular ultrasound virtual histology (IVUS-VH) of culprit lesions. The incidence of major adverse cardiovascular events (MACE) including all-cause mortality, non-fatal MI, stroke and late revascularization were recorded during hospitalization and follow-up. During follow-up (median 41 months), the incidence of MACE did not significantly differ among patients with or without all 3 high-risk plaque features on IVUS-VH (15.1 vs. 16.2%; p?=?0.39). In contrast, patients with elevated hs-CRP and NLR levels were at significant risk for MACE [32.7 vs. 5.8%; hazard ratio (HR) 7.85; p?<?0.001 and 43.9 vs. 6.9%; HR 8.44; p?<?0.001, respectively]. High-risk plaque features had no incremental usefulness to predict future MACE. However, the incorporation of hs-CRP and NLR into a model with conventional clinical and procedural risk factors significantly improved the C-statistic for the prediction of MACE (0.76–0.89; p?=?0.04). High-risk plaque features identified by IVUS-VH in culprit lesions were not associated with future MACE in patients with STEMI receiving DES. However, elevated hs-CRP and NLR levels were significantly associated with poorer outcomes and had incremental predictive values over conventional risk factors.     

Implication of coronary CT angiography combined with four-dimensional speckle tracking echocardiography for predicting major adverse cardiac events

Coronary computed tomography angiography (CCTA) can provide abundant information about the anatomy of the coronary artery. However, this modality is limited in evaluation of myocardial function. Four-dimensional speckle tracking echocardiography (4DSTE) is a novel and sensitive technique for quantitative evaluation of myocardial deformation. We estimated the value of these imaging modalities to predict the risk of MACE in 209 patients with suspected coronary artery disease(CAD) after a median follow-up of 727 days. Three models were established: (1) CCTA alone, (2) CCTA combined with 4DSTE, and (3) CCTA combined with 4DSTE and clinical risk factors. Forty-six (22.0%) patients developed MACE. The hazard ratio (HR) of CCTA classification to predict the risk of MACE was greater (HR?=?4.86) than for other parameters, including B-type natriuretic peptide (BNP) (HR?=?2.44) and left ventricular ejection fraction (LVEF) (HR?=?0.40). The area under the curve of models 2 and 3 to predict MACE was significantly greater than that of model 1 (0.92 and 0.93 vs. 0.84, respectively, p?<?0.001). We conclude that there is direct relationship between CCTA classification and MACE risk. CCTA combined with 4DSTE can improve the ability of CCTA to predict the risk of MACE. This approach provides cardiologists a noninvasive, objective, and efficient method to predict MACE.     

Rb-82 PET/CT left ventricular mass-to-volume ratios

Left ventricular (LV) mass:volume ratios indexed to body size (Mi/Vi) provide risk stratification for cardiac events. We sought to determine whether Rb-82 PET mass and volume indices are similar to MRI normal values for low likelihood subjects, and whether abnormal indices are related to abnormal myocardial blood flow (MBF). Data were analyzed retrospectively for 194 patients referred for rest/stress Rb-82 PET. LV EF, volume and mass values were calculated and mass:volume ratios were indexed to patients’ height and weight. MBF was computed from the first pass dynamic component of PET data. 53 patients at low likelihood of CAD had PET Mi/Vi?=?1.35?±?0.27, consistent with the MRI literature range of 1.0–1.5. Compared to patients with normal indexed volume (Vi), patients with abnormally high Vi had lower rest MBF (0.56?±?0.24 vs 0.93?±?0.57 ml/g/min, p?=?0.0001), and lower stress MBF (0.97?±?0.52 vs. 1.83?±?0.96 ml/g/min, p?<?0.0001). Stress EF?<?50% predicted abnormal Vi with 90% accuracy. Patients with Mi/Vi?<?1.0 had abnormally low rest EF (45?±?16% vs. 60?±?15%, p?<?0.0001) and low rest MBF (0.58?±?0.25 vs. 0.96?±?0.59 ml/g/min, p?<?0.0001). In our study population, abnormal LV volume and mass correlated with lower rest and stress MBF and EF, suggesting that the pathophysiologic explanation of these patients’ increased risk is more extensive obstructive CAD.     

Performance of adenosine “stress-only” perfusion MRI in patients without a history of myocardial infarction: a clinical outcome study

To assess the diagnostic value of adenosine “stress-only” myocardial perfusion MR for ischemia detection as an indicator for coronary angiography in patients without a prior myocardial infarction and a necessity to exclude ischemia. Adenosine perfusion MRI was performed at 1.5 T in 139 patients with a suspicion of ischemia and no prior myocardial infarction. After 3 min of adenosine infusion a perfusion sequence was started. Patients with a perfusion defect were referred to coronary angiography (CAG). Patients with a normal perfusion were enrolled in follow-up. Fourteen out of 139 patients (10.1%) had a perfusion defect indicative of ischemia. These patients underwent a coronary angiogram, which showed complete agreement with the perfusion images. 125 patients with a normal myocardial perfusion entered follow-up (median 672 days, range 333–1287 days). In the first year of follow-up one Major Adverse Coronary Event (MACE) occurred and one patient had new onset chest pain with a confirmed coronary stenosis. Reaching a negative predictive value for MACE of 99.2% and for any coronary event of 98.4%. At 2 year follow-up no additional MACE occurred. Sensitivity of adenosine perfusion MR for MACE is 93.3% and specificity and positive predictive value are 100%. Adenosine myocardial perfusion MR for the detection of myocardial ischemia in a “stress-only” protocol in patients without prior myocardial infarctions, has a high diagnostic accuracy. This fast examination can play an important role in the evaluation of patients without prior myocardial infarctions and a necessity to exclude ischemia.     

Diffuse fibrosis is common in the left,but not in the right ventricle in patients with transposition of the great arteries late after atrial switch operation

In adult patients with transposition of the great arteries (TGA) late after atrial switch operation (AtSO), each of the ventricles is faced with a profoundly different pressure regimen from the one they are meant to support in normal conditions. The extent of diffuse fibrosis of the right ventricle (RV) and left ventricle (LV) in these patients remains incompletely investigated. Aim of this study was to quantify the degree of fibrosis of the unloaded LV and of the overloaded RV by determining the myocardial extracellular volume (ECV) with non-invasive techniques as T1 mapping. We determined ECV by cardiac magnetic resonance (CMR) in 10 patients (36.8?±?5.3 years old) with TGA late after AtSO, without relevant pulmonary stenosis, by acquiring T1-maps of the myocardium before and 10 min after injection of Gadolinium-based contrast agent. ECV of the inferior wall (36% (33–41%)) and of the lateral wall (37% (35–39%)) of the LV was significantly increased compared to the ECV of the RV (27% (25–29%)), in both comparisons P?<?0.0001. Long-time LV unloading following atrial switch procedures leads to severe myocardial fibrosis of the subpulmonary LV. T1 mapping CMR might be useful for selection of patients with atrial switch operation, in whom reestablishment of the LV as a systemic ventricle by staged arterial switch operation is planned. However larger studies and newer higher resolution methods for T1-mapping are needed to determine the role of ECV in the decision of a surgical intervention in this kind of population.     

Serial assessment of left ventricular morphology and function in a rodent model of ischemic cardiomyopathy

Left ventricular remodelling (LVr) occurs post myocardial infarction (MI), predisposing people to heart failure (HF). LV mechanics and morphology are important in this process. We hence sort to characterize LV mechanics and geometry in a post-MI rodent model. Thirty-two male Sprague–Dawley rats (150–200 g) sustained MI (n?=?24) or sham (Sham; n?=?8) surgery. In another six sham rats invasive blood pressure measurements were performed. Ultrasound imaging was done at baseline, and 1, 3, 7, 14, 30 and 60 days following surgery, and LV mechanics and morphology assessed. LV volumes increased with time (p?<?0.01), at a greater rate in the MI group than the Sham group (p?<?0.01). Strain was impaired in MI rats at day 1 (13.50?±?6.64 vs. 25.71?±?4.94%, p?<?0.01) and remained impaired at day 60 (14.07?±?5.37 vs. 22.98?±?5.87%, p?<?0.01). Strain rate was lower at day 1 (4.11?±?1.29 vs. 8.10?±?2.18%/s, p?<?0.01), remained lower throughout follow-up (p?<?0.01), and decreased at a greater rate in MI rats (p?<?0.01). Mean systolic (204?±?43 vs. 322?±?75 1/m, p?<?0.01) and diastolic (167?±?21 vs. 192?±?11 1/m, p?<?0.01) curvature was lower in the MI rats at day 1 post surgery and throughout follow-up (p?<?0.01). Maximum principal curvature decreased throughout time (p?<?0.01), while minimum principal curvature did not (p?=?0.86). Wall stress increased significantly after infarction in MI rats (p?<?0.01). ST-elevation myocardial infarction (STEMI) changed LV shape and contractile function. The assessment of these indices may prove useful in understanding LVr and the development of HF.     

A fast and effective method of quantifying myocardial perfusion by magnetic resonance imaging

The quantification of global myocardial blood flow (MBF) by measuring coronary sinus flow by magnetic resonance (MRI) was demonstrated to be very well correlated with positron emission tomography (PET). We proposed a new method for the quantification of regional myocardial perfusion with MRI by the integration of MBF and first pass technique. The aim of this study was to validate this new method for quantification of regional perfusion by comparing it with 13NH13-PET in swine models of myocardial infarction and in humans in resting and hyperemic conditions. MRI and 13NH3-PET was performed in 2 healthy swine, 11 swine models of myocardial infarction (5 reperfused, 6 non reperfused) and in 12 humans at rest and during hyperemia. MBF was estimated by MRI through the quantification of coronary sinus flow and left ventricular (LV) mass. The upslope of signal intensity (SI-upslope) of each myocardial segment was obtained by the first pass gadolinium technique. Regional SI-upslope was indexed by the upslope of the entire left ventricular myocardium (global upslope). Regional myocardial perfusion was estimated as the product of MBF and SI-upslope/global upslope. Regional perfusion was also estimated by 13NH3-PET. A close agreement of the MRI and PET techniques for measurement of regional myocardial perfusion was found in all myocardial segments by Bland–Altman analysis (mean difference 5.1 %; limits of agreement, ?37.2–27.5 %). With the integration of the first pass technique and the measurement of global MBF by coronary sinus flow/LV mass, MRI allows direct quantification of regional myocardial perfusion.     

Intramyocardial dissecting hematoma in anterior wall ST elevation myocardial infarction: impact on left ventricular remodeling and prognosis

Intramyocardial dissecting hematoma is an uncommon complication of myocardial infarction potentially leading to cardiac rupture. The aim of the present study was to investigate coronary reperfusion results, left ventricular (LV) function recovery and remodeling and clinical outcomes in patients with anterior STEMI complicated by intramyocardial hematoma. We prospectively studied 87 patients (mean age 59?±?10 years; 88% male) with anterior STEMI (42 with intramyocardial hematoma) in order to evaluate coronary reperfusion results, LV remodeling (≥15% increase in end-systolic volume) and clinical outcomes (cardiac death, non-fatal reinfarction, and hospitalization for congestive heart failure) at 24 months. Thrombolysis in myocardial infarction (TIMI) flow score and myocardial blush grade (MBG) were assessed both pre- and post-percutaneous coronary intervention (PCI) and speckle-tracking echocardiography was performed post PCI and at 6-month follow-up. Patients with hematoma had lower post-PCI TIMI score and MBG, higher heart rate, worse LV ejection fraction and longitudinal or rotational function than their counterparts. LV remodeling occurred in 33 (78.6%) patients with hematoma and 11 (24.4%) patients without (p?<?0.001). Independent predictors of LV remodeling were heart rate (p?=?0.018), MBG (p?=?0.036) and presence of hematoma (p?<?0.001). Hematoma (log-rank test, χ²?=?9.849; p?=?0.002) and LV remodeling (log-rank test, χ²?=?13.770; p?<?0.001) were associated to a higher rate of adverse events. Cox analysis identified LV remodeling as the only independent predictor of adverse events (hazard ratio?=?3.912; 95% confidence interval, 1.429–10.714; p?=?0.008). Intramyocardial dissecting hematoma complicating anterior STEMI is an independent determinant of LV remodeling and is associated to poor prognosis.     

T1 mapping in children and young adults with hypertrophic cardiomyopathy

To assess the global and segmental left ventricular (LV) native T1 and extracellular volume fraction (ECV) in children and young adults with hypertrophic cardiomyopathy (HCM) compared to a control cohort. The study population included 21 HCM patients (mean 14.1?±?4.6 years) and 21 controls (mean 15.7?±?1.5 years). Native modified Look-Locker inversion recovery sequence was performed before and after contrast injection in 3 short axis planes. Global and segmental LV native T1 and ECV were quantified and compared between HCM patients and controls. Mean native T1 in HCM patients and controls was 1020.4?±?41.2 and 965.6?±?30.2 ms respectively (p?<?0.0001). Hypertrophied myocardium had significantly higher native global T1 and global ECV compared to non-hypertrophied myocardium in HCM (p?<?0.0001,?=?0.14 and 0.048,?=?0.01 respectively). In a subset of patients, ECV was higher in LV segments with LGE compared to no LGE (p?<?0.0001). No significant correlation was identified between global native T1 and ECV and parameters of LV structure and function. Native T1 cut-off of 987 ms provided the highest sensitivity (95?%) and specificity (91?%) to separate HCM patients from controls. Global and segmental native T1 are elevated in HCM patients. LV segments with hypertrophy and/or LGE had higher ECV in a subset of HCM patients. LV native T1 and ECV do not correlate with parameters of LV structure and function. T1 in children and young adults may be used as a non-invasive tool to assess for HCM and related fibrosis.     

Clinical outcomes of complete revascularization using either angiography-guided or fractional flow reserve-guided drug-eluting stent implantation in non-culprit vessels in ST elevation myocardial infarction patients: insights from a study based on a systematic review and meta-analysis

Current guidelines recommend that percutaneous coronary intervention (PCI) should be restricted to the culprit vessel in ST elevation myocardial infarction (STEMI) patients with multi-vessel disease (MVD) and without cardiogenic shock. However, newer data suggests that performing complete revascularization (CR) in MVD patients may lead to better outcomes compared to intervention in the culprit vessel only. The aim of this meta-analysis is to examine the available data to determine if CR (using either angio- or fractional flow reserve guidance—FFR) following primary PCI in STEMI patients without cardiogenic shock impacts clinical outcomes. Meta-analysis was performed by conducting a literature search of PubMed from January 2004 to July 2017. Pooled estimates of outcomes, presented as odds ratios (OR) [95% confidence intervals], were generated using random-effect models. A total of 9 studies (3317 patients) were included. CR showed a significant MACE reduction (OR 0.49, 95% CI 0.36–0.66, p?<?0.001); All-cause mortality (OR 0.69, 95% CI 0.48–0.98, p?=?0.04) and repeat revascularization (OR 0.38, 95% CI 0.28–0.51, p?<?0.001) at?≥?12 months follow-up. The FFR-guiding CR group presented a MACE reduction (odds ratio 0.52, 95% CI 0.30–0.90, p?=?0.02) due to a decrease of repeat revascularization (OR 0.41, 95% CI 0.21–0.80, p?=?0.009). Overall, performing complete revascularization in STEMI patients showed a MACE reduction, all-cause death and repeat revascularization. Compared to culprit-only revascularization, treating multi-vessel disease in STEMI patients using FFR guidance is associated with decreased incidence of MACE, due to a decreased rate of revascularization.     

Predictors of left ventricular remodeling after ST-elevation myocardial infarction

Adverse left ventricular (LV) remodeling after acute ST-elevation myocardial infarction (STEMI) is associated with morbidity and mortality. We studied clinical, biochemical and angiographic determinants of LV end diastolic volume index (LVEDVi), end systolic volume index (LVESVi) and mass index (LVMi) as global LV remodeling parameters 4 months after STEMI, as well as end diastolic wall thickness (EDWT) and end systolic wall thickness (ESWT) of the non-infarcted myocardium, as compensatory remote LV remodeling parameters. Data was collected in 271 patients participating in the GIPS-III trial, presenting with a first STEMI. Laboratory measures were collected at baseline, 2 weeks, and 6–8 weeks. Cardiovascular magnetic resonance imaging (CMR) was performed 4 months after STEMI. Linear regression analyses were performed to determine predictors. At baseline, patients were 21% female, median age was 58 years. At 4 months, mean LV ejection fraction (LVEF) was 54?±?9%, mean infarct size was 9.0?±?7.9% of LVM. Strongest univariate predictors (all p?<?0.001) were peak Troponin T for LVEDVi (R²?=?0.26), peak CK-MB for LVESVi (R²?=?0.41), NT-proBNP at 2 weeks for LVMi (R²?=?0.24), body surface area for EDWT (R²?=?0.32), and weight for ESWT (R²?=?0.29). After multivariable analysis, cardiac biomarkers remained the strongest predictors of LVMi, LVEDVi and LVESVi. NT-proBNP but none of the acute cardiac injury biomarkers were associated with remote LV wall thickness. Our analyses illustrate the value of cardiac specific biochemical biomarkers in predicting global LV remodeling after STEMI. We found no evidence for a hypertrophic response of the non-infarcted myocardium.     

Intracoronary versus intravenous bolus abciximab application in patients with ST-elevation myocardial infarction undergoing primary percutaneous coronary intervention: 6-month effects on infarct size and left ventricular function

Background

Administration of abciximab during primary percutaneous coronary intervention (PCI) reduces major adverse cardiac events (MACE) in patients with ST-elevation myocardial infarction (STEMI). Intracoronary (IC) abciximab bolus application during PCI results in high local drug concentration, improved perfusion, reduction of infarct size, and less microvascular obstruction early after infarction. Aim of this study was to investigate whether the early benefits of an IC abciximab administration in STEMI patients undergoing PCI are sustained at 6?months.

Methods

We performed 6-month follow-up of 154 STEMI patients undergoing PCI, who were randomised to either IC (n?=?77) or intravenous (IV) (n?=?77) bolus abciximab administration with subsequent 12-h intravenous infusion. The primary endpoint was infarct size at 6-month follow-up as assessed by delayed enhancement magnetic resonance imaging. Clinical end points were MACEs within 6?months after infarction.

Results

The median infarct size after 6?months was significantly reduced in the IC abciximab group (16.7 vs. 24.1%, p?=?0.002). A significant recovery of LV function was only observed in the IC abciximab group (p?<?0.001), and IC abciximab group patients had significantly less adverse remodelling as compared to standard IV abciximab treatment (p?=?0.03). These beneficial effects also translated into a strong trend towards a reduced MACE rate in the IC abciximab group at 6-month follow-up (10 vs. 21%, p?=?0.07).

Conclusions

Intracoronary abciximab application in STEMI patients undergoing PCI is superior to standard IV treatment with respect to infarct size, recovery of LV function and reverse remodelling 6?months after infarction.