Iosif Koutagiar

Inflamed human carotid plaques evaluated by PET/CT exhibit increased temperature: insights from an in vivo study

Aims To explore the relationship between temperature measurements derived by microwave radiometry (MWR) and carotid flurodeoxyglucose (FDG) uptake and assess their association with histological and immunohistochemistry findings in patients with high-grade carotid stenosis. Methods and results In 21 patients undergoing carotid endarterectomy, carotid inflammation was evaluated by both FDG positron emission/computed tomography (FDG-PET/CT) imaging and MWR measurements. Carotid inflammation was assessed by PET/CT as target-to-background ratio (TBR) by obtaining measurements in consecutive axial slices 2 cm below to 2 cm above the carotid bifurcation. Temperature difference (ΔT) by MWR was assigned as the maximum-minimum temperature measurements over the corresponding carotid segments. The extent of lipid core, calcification as well as CD68 and CD31 levels were also assessed. There was a significant correlation between ΔT values and FDG uptake (R = 0.40, P = 0.01), but no correlation between the degree of angiographic stenosis and ΔT values (R = -0.02, P = 0.91) or PET/CT measurements (R = -0.28, P = 0.86). Patients with plaques containing high lipid core extension or low calcification exhibited higher ΔT (P = 0.001 and P < 0.001, respectively) and FDG uptake values (P = 0.02 and P = 0.02, respectively). Patients with plaques containing increased CD68 expression exhibited higher ΔT and FDG uptake measurements. Conclusion Carotid plaque inflammation was evaluated by temperature measurements, which were correlated with FDG-PET/CT indices, confirmed by histopathology and immunohistochemistry findings. Structural changes did not predict inflammatory process. The implications of these findings in risk stratification and management of patients with carotid atherosclerosis and the precise algorithm for potential clinical utilization of MWR and PET/CT remain to be determined.

Diagnosis and management of phantom tachycardias based on an electrophysiologically guided approach

BACKGROUND Non-documented palpitations, or phantom tachycardias, are palpitations deemed to be of unknown origin after evaluation with conventional diagnostic tools, such as 12-lead electrocardiogram and Holter recordings. Our aim was to determine the diagnostic value of an electrophysiologic study (EPS) and its role in the management of patients presenting with non-documented palpitations. METHODS We performed EPS in 78 consecutive patients with repeatable, poorly tolerated symptoms of paroxysmal, non-documented tachycardia, the absence of structural heart disease and at least one 24-h Holter recording. The duration and frequency of palpitations was registered in each patient. RESULTS Long-lasting palpitations (>1 hour) were present in 15.4% of patients. Half of patients reported symptoms less often than once per week. Only 13/78 patients (16.6%) had normal EPS findings, while dual pathways at the AV node ± echo beats were identified in another 13 patients without inducible tachycardia. At least one tachycardia event was induced in 52 patients (66.6%). AVNRT was provoked in 32 patients (41.2%). Ablation was performed in 14/52 patients with inducible tachycardia (26.9%). Slow pathway ablation was also performed in three patients with dual AV pathways and atrial echo-beats but without provoked tachycardia. Follow-up data were available in 52 patients, and 84.6% had fewer or no clinical recurrences. CONCLUSIONS EPS is safe and of enhanced diagnostic value in patients with unexplained palpitations because only 1/6 had negative results. EPS also provided an explanation about the mechanism of arrhythmia and successfully guided the management of these patients, as well as enhanced improvement in the quality of life.

Female gender is independently associated with increased carotid temperatures in patients with coronary artery disease

BACKGROUND Limited are the data regarding the sex differences in functional carotid artery characteristics. Microwave Radiometry (MWR) is a new noninvasive method, which measures in vivo instantly the internal temperatures of tissues, reflecting inflammation. The aim of the present study was to investigate whether in patients with coronary artery disease (CAD), gender related differences apply in carotid plaque functional characteristics, as assessed by MWR. METHODS Consecutive patients with significant CAD were included in the study. All patients underwent evaluation of both carotid arteries by 1) ultrasound and 2) MWR. During ultrasound common carotid IMT and plaque thickness were assessed according to Mannheim consensus. During MWR measurements, temperature difference (ΔT) was assigned as maximal temperature along the carotid artery minus minimum. ΔT ≥0.90°C was assigned as high ΔT. RESULTS In total 364 patients with significant CAD were included in the study. Of these 54 were female and 310 were male. Max plaque thickness and ccIMT were similar between males and females (2.38±1.16 vs. 2.46±1.12mm, p=0.63 and 0.944±0.172 vs. 0.942±0.169mm, p=0.96). Carotid arteries of females showed higher ΔT values (1.16±0.48 vs 0.87±0.45°C, p<0.001). Interestingly, females had more commonly high ΔT values bilaterally (35.2% vs 15.5%, p=0.001). In multivariate analysis, female sex was independently associated with bilateral high ΔT, when adjusted to potential covariates (OR=2.78, 95% CI=1.42-5.45, p=0.003). CONCLUSIONS In patients with CAD, sex specific differences apply in functional but not in structural carotid artery characteristics. Whether this discrepancy has prognostic significance, remains to be clarified in future studies.

HIGH BILATERAL CAROTID TEMPERATURES PREDICT INCREASED TWO-YEAR CARDIOVASCULAR EVENT RATE

Inflammation is a recognized characteristic of vulnerable atherosclerotic plaque. Microwave radiometry (MWR) allows the noninvasive assessment of the internal temperature of carotid arteries. In the present study we investigated whether patients with documented coronary artery disease (CAD) and

FAMILIAL COMBINED HYPERLIPIDEMIA IS CHARACTERIZED BY HIGHER HEPATIC FDG UPTAKE AND VISCERAL ADIPOSE TISSUE VOLUME COMPARED TO HETEROZYGOUS FAMILIAL HYPERCHOLESTEROLAEMIA

Familial combined hyperlipidaemia (FCH) phenotype is associated with increased prevalence of non-alcoholic fatty liver disease and obesity. No data exists regarding the impact of heterozygous familial hypercholesterolaemia (heFH), another type of familial dyslipidaemia, on liver function and

Diagnostic modalities in peripheral artery disease

HIGHLIGHTSABI is a well‐established risk predictor.DUS is often the first‐line test both for screening and diagnosis of PAD.In asymptomatic patients with carotid artery stenosis 60–99%, DUS could identify patients suitable for CEA.CTA and MRA provide with a ‘roadmap’ of the vascularization.Digital subtraction angiography has been mostly replaced by other less invasive methods except for below‐the‐knee arterial disease. &NA; Peripheral artery disease (PAD) affects approximately one in five persons older than 70 years of age and it is often present in patients with concomitant vascular disease in different body territories (e.g. coronary artery disease). Diagnosis at an early stage is important in order to achieve improvement in patients symptoms and prognosis. Remarkable improvements in the field of noninvasive and invasive imaging techniques have led to an advanced level the management of patients with PAD. Throughout this review article, the clinically available diagnostic modalities in PAD are presented. Strong and weaker points are stressed out in a manner that elucidates that no perfect diagnostic method exists. Based on the patients individual profile, as well as on certain aspects of the disease (e.g. morphology of carotid plaque lesions) the attending physician will ultimately decide which diagnostic path will lead to a prompt and correct diagnosis of PAD with the minimum amount of exams and risk for the patient.

18F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomographic Imaging Detects Aortic Wall Inflammation in Patients With Repaired Coarctation of Aorta

Patients with surgically repaired coarctation of aorta (RCoA) are at increased cardiovascular mortality risk. Inflammation is an important element in RCoA.1,2 Positron emission tomography/computed tomography (PET/CT) with 18F-fluorodeoxyglucose (18F-FDG) is the gold-standard imaging modality to noninvasively assess vascular inflammation in vivo. In this pilot study, we explore the value of 18F-FDG PET/CT imaging in assessing aortic wall inflammation in RCoA subjects. A total of 15 patients with successful RCoA and 15 age- and sex-matched control subjects who have undergone treatment for lymphoma—a potentially high cardiovascular risk group—but were disease-free at the time of enrollment underwent 18F-FDG PET/CT to evaluate aortic wall inflammation. RCoA patients also underwent measurement of arterial elastic properties (augmentation index and carotid–femoral pulse wave velocity) by SphygmoCor (AtCor Medical, Sydney, Australia). The central arterial blood pressure was derived from the use of a generalized transfer function. Plasma levels of IL-6 (interleukin-6), TGF-β (transforming growth factor-β), and macrophage colony-stimulating factor were determined as markers of systemic inflammation and aortic wall remodeling. Patients with hypercholesterolemia or diabetes mellitus were excluded. To test the hypothesis that aortic coarctation is associated with increased aortic wall inflammation even in the absence of adverse hemodynamic burden to the aorta, patients with recoarctation were also …

Characteristics and management of 1093 patients with clinical diagnosis of familial hypercholesterolemia in Greece: Data from the Hellenic Familial Hypercholesterolemia Registry (HELLAS-FH)

BACKGROUND AND AIMS Although familial hypercholesterolemia (FH) is one of the most common genetic disorders, it remains largely underdiagnosed and undertreated. The Hellenic Atherosclerosis Society has established the Hellenic Familial Hypercholesterolemia (HELLAS-FH) Registry, part of the Familial Hypercholesterolemia Studies Collaboration (FHSC), to evaluate the characteristics and management of patients with FH in Greece. METHODS Patients with diagnosed FH were recruited by a network of sites throughout Greece. The prevalence of cardiovascular disease (CVD) risk factors, as well as management of FH, was recorded. RESULTS This interim analysis included 1093 patients (556 male; 950 adults). The median age of FH diagnosis was 42.2 years (interquartile range 27.2-53.0). A family history of CVD was present in 47.8%, while 21.1% of patients had a personal history of CVD. At diagnosis, low-density lipoprotein cholesterol (LDL-C) was 241 ± 76 mg/dL in adults and 229 ± 57 mg/dL in children. Overall, 63.1% of the patients were receiving hypolipidemic drug treatment, mainly statins, at inclusion in the registry. Mean LDL-C of patients receiving drug treatment was 154 ± 76 mg/dL in adults and 136 ± 47 mg/dL in children. The majority of treated patients (87.9%) did not achieve LDL-C targets. CONCLUSIONS FH in Greece is characterized by a significant delay in diagnosis and a high prevalence of both family and personal history of established CVD. The vast majority of FH patients do not achieve LDL-C targets. Improved awareness and management of FH are definitely needed.

INCREASED ONE YEAR CARDIOVASCULAR EVENT RATE IN PATIENTS WITH CORONARY ARTERY DISEASE AND BILATERAL CAROTID ARTERY INFLAMMATION

Controversy exists regarding the prognostic role of both local and systemic inflammation in coronary artery disease (CAD). Microwave radiometry (MWR) allows the valid, in vivo, noninvasive assessment of the internal temperature of carotid arteries, reflecting local inflammation. The aim of the