Konstantinos Stathogiannis

First In Vivo Application of Microwave Radiometry in Human Carotids: A New Noninvasive Method for Detection of Local Inflammatory Activation

OBJECTIVES This study investigated whether temperature differences: 1) can be measured in vivo noninvasively by microwave radiometry (MR); and 2) are associated with ultrasound and histological findings. BACKGROUND Studies of human carotid artery samples showed increased heat production. MR allows in vivo noninvasive measurement of internal temperature of tissues. METHODS Thirty-four patients undergoing carotid endarterectomy underwent screening of carotid atherosclerosis by ultrasound and MR. Healthy volunteers were enrolled as a control group. During ultrasound study, plaque texture, plaque surface, and plaque echogenicity were analyzed. Temperature difference (ΔT) was assigned as maximal minus minimum temperature. Association of thermographic with ultrasound and histological findings was performed. RESULTS ΔT was higher in atherosclerotic carotid arteries compared with the carotid arteries of controls (p < 0.01). Fatty plaques had higher ΔT compared with mixed and calcified (p < 0.01) plaques. Plaques with ulcerated surface had higher ΔT compared with plaques with irregular and regular surface (p < 0.01). Heterogeneous plaques had higher ΔT compared with homogenous (p < 0.01). Specimens with thin fibrous cap and intense expression of CD3, CD68, and vascular endothelial growth factor (VEGF) had higher ΔT compared with specimens with thick cap and low expression of CD3, CD68, and VEGF (p < 0.01). CONCLUSIONS MR provides in vivo noninvasive temperature measurements of carotid plaques, reflecting plaque inflammatory activation.

A honeycomb-like structure in the left anterior descending coronary artery: demonstration of recanalized thrombus by optical coherence tomography.

A 41-year-old man presented with atypical chest pain in another hospital with an electrocardiogram negative for ischemia, but with slightly elevated troponin I levels (0.12 ng/ml). The patient underwent cardiac catheterization within 24 h. Coronary angiography revealed 2 nonsignificant lesions at

In vivo measurement of plaque neovascularisation and thermal heterogeneity in intermediate lesions of human carotid arteries

Objectives Both neoangiogenesis and inflammation contribute in atherosclerosis progression. Contrast-enhanced ultrasound (CEUS) provides visualisation of plaque neovascularisation. Microwave radiometry (MR) allows in vivo non-invasive measurement of temperature of tissues, reflecting inflammatory activation. We assessed the association of carotid plaque temperature, measured by MR, with plaque neovascularisation assessed by CEUS in intermediate lesions. Methods Consecutive patients with coronary artery disease and carotid atherosclerosis underwent carotid ultrasound imaging, CEUS and MR. Plaque texture, plaque surface and plaque echogenicity were analysed. Contrast enhancement (CE) by CEUS was defined as the % percentage of signal intensity difference, prior and post contrast infusion. Thermal heterogeneity (ΔT) was assigned as maximal temperature along the carotid artery minus minimum. Results Eighty-six carotid arteries of 48 patients were included. Fatty plaques had higher CE% and ΔT compared with mixed and calcified (p<0.01 for all comparisons). Heterogeneous plaques had higher CE% and ΔT compared with homogenous (p<0.01 for all comparisons). Plaques with irregular surface had higher CE% and ΔT compared with plaques with regular (p<0.01 for all comparisons). There was a good correlation between ΔT and CE (R=0.60, p<0.001). Conclusions Carotid plaque neovascularisation on CEUS examination is associated with increased thermal heterogeneity and ultrasound characteristics of plaque vulnerability in intermediate lesions.

One-year outcomes after direct transcatheter aortic valve implantation with a self-expanding bioprosthesis. A two-center international experience.

BACKGROUND Balloon aortic valvuloplasty (BAV) is considered to be an essential part of the transcatheter aortic valve implantation (TAVI) procedure and is being performed routinely. At present there is insufficient long-term data as to the benefits of routine BAV prior to TAVI. AIM The aim of this study was to evaluate the safety of direct TAVI and the mortality rate at 1-year in patients undergoing TAVI with or without BAV with a self-expanding bioprosthesis. METHODS Between January 2008 and September 2013 consecutive patients undergoing TAVI with the Medtronic CoreValve in two experienced centers in Athens, Greece and in Siegburg, Germany were studied. All data were prospectively collected and retrospectively analyzed. Primary endpoint was mortality at 1 year. Procedural data and clinical data (bleeding, vascular complications and echocardiographic parameters) were analyzed. RESULTS A total of 210 patients undergoing TAVI were evaluated (non-direct=120 patients, direct=90 patients). All-cause mortality at 30 days and at 1 year was similar in both groups (4% in non-direct versus 2% in direct, p=0.6 and 15% in non-direct versus 11% in direct, p=0.5, respectively). Device success rate was similar in both groups (77% in non-direct versus 83% in direct, p=0.2). Major vascular complications were comparable for both groups (5% in non-direct versus 3% in direct, p=0.5). The direct group had less moderate/severe paravalvular leakage than the non-direct group after the device implantation (7% versus 33%, p<0.01). CONCLUSIONS Performing direct TAVI with the self-expanding bioprosthesis is safe and feasible showing similar mortality rates compared to patients undergoing non-direct TAVI at 30 days and at 1-year.

Morphological and Functional Assessment of Carotid Plaques Have Similar Predictive Accuracy for Coronary Artery Disease

Background and Purpose— Microwave radiometry allows noninvasive in vivo measuring of internal temperature of tissues reflecting inflammation. In the present study, we evaluated the predictive accuracy of this method for the diagnosis of coronary artery disease (CAD). Methods— Consecutive patients (n=287) scheduled for coronary angiography were included in the study. In carotid arteries of both groups, the following measurements were performed: (1) intima-media thickness (IMTmax) and (2) temperature measurements by microwave radiometry (&Dgr;Tmax). C-statistic and net reclassification improvement were used to compare the prediction ability of the markers IMTmax and &Dgr;Tmax for the presence of CAD and multivessel CAD. Results— Of 287 patients, 239 had stenoses ≥50% (CAD group), and 48 did not have significant stenoses (NO-CAD group). &Dgr;Tmax was an independent predictor for the presence of CAD and multivessel CAD, showing similar predictive accuracy to intima-media thickness, as assessed by c-statistic and net reclassification improvement. Conclusions— Local inflammatory activation, as detected by microwave radiometry, has similar predictive accuracy to intima-media thickness for the presence and extent of CAD.

MicroRNAs in Arterial Hypertension

Arterial hypertension is an epidemic currently affecting almost a billion people worldwide. The consequences from high blood pressure vary, from peripheral arterial disease and chronic kidney failure to acute myocardial infarction and stroke. MicroRNAs (miRNAs) are small non-coding RNA molecules comprised of 22-26 nucleotides and provide posttranscriptional protein expression regulation. The many biological processes in which they are implicated, such as cell proliferation, apoptosis, metabolism, cell differentiation and morphogenesis confirms the functional significance of miRNAs. It has been found that miRNAs are expressed in cardiovascular disorders and seem to be important players in the pathogenesis of arterial hypertension. The elucidation of which miRNAs are key players and at what level is of high value since it is necessary in order to better understand the mechanisms underlying hypertension, thus leading to better diagnostic modalities and therapeutic regimes.

Vulnerable Atherosclerotic Plaque: From the Basic Research Laboratory to the Clinic

Coronary heart disease is the commonest cause of death in Western countries, and atherosclerotic plaques that are prone to rupture have been implicated in the pathogenesis of acute coronary syndromes (ACS). Intensive research has been directed at plaque detection, and various invasive methods have been developed thus far that fulfill this purpose and a lot of them are being applied in the clinical setting. Since invasive methods cannot be used for primary prevention, non-invasive imaging modalities are being studied to enhance the diagnostic armory of clinicians in their difficult task of detecting and preventing ACS.

Microwave radiometry: a new non-invasive method for the detection of vulnerable plaque

Atherosclerosis and its consequences are the most rapidly growing vascular pathology, with myocardial infarction and ischemic cerebrovascular accident to remain a major cause of premature morbidity and death. In order to detect the morphological and functional characteristics of the vulnerable plaques, new imaging modalities have been developed. Intravascular thermography (IVT) is an invasive method, which provides information on the identification of the high-risk atheromatic plaques in coronary arteries. However, the invasive character of IVT excludes the method from primary prevention. Microwave radiometry (MR) is a new non-invasive method, which detects with high accuracy relative changes of temperature in human tissues whereas this thermal heterogeneity is indicative of inflammatory atherosclerotic plaque. Both experimental and clinical studies have proved the effectiveness of MR in detecting vulnerable plaque whereas recent studies have also revealed its association with plaque neoangiogenesis as assessed by contrast enhanced carotid ultrasound (CEUS).

Reduction of Para-Ring Regurgitation After Transcatheter Mitral Valve Replacement Into a Failed Mitral Annuloplasty Ring

Transcatheter valve-in-ring procedure has shown in a number of small case series to be feasible, safe, and able to offer short-term clinical and hemodynamic improvement in selected high-risk patients after failed surgical mitral annuloplasty ring repair [(1)][1]. Hereby, we report a case of a 70-

Successful management of a twice complicated case by implantation of three CoreValve prostheses

of three CoreValve prostheses George Latsios , Kostantinos Toutouzas , Dimitris Tousoulis ⁎, Andreas Synetos , Antonios Mastrokostopoulos , Konstantinos Stathogiannis , Themis Spyridopoulos , Ulrich Gerckens , Christodoulos Stefanadis a a 1st Department of Cardiology, “Hippokration” Hospital, University of Athens, Greece b Department of Radiology, “Penteli” Hospital, Greece c Gemeinschaftskrankenhaus Bonn, Germany