Socrates Korovesis

Transcoronary transplantation of autologous mesenchymal stem cells and endothelial progenitors into infarcted human myocardium.

The aim of the study was to investigate whether a combination of mesenchymal stem cells (MSCs) capable of differentiating into cardiac myocytes and endothelial progenitors (EPCs) that mainly promote neoangiogenesis might be able to facilitate tissue repair in myocardial scars. Previous studies have shown that intracoronary transplantation of autologous bone marrow stem cells results in improvement of contractility in infracted areas of human myocardium. Eleven patients with an anteroseptal myocardial infarction (MI) underwent transcoronary transplantation of bone marrow‐derived MSCs and EPCs to the infarcted area through the left anterior descending artery. Eleven age‐ and sex‐matched patients served as controls. Wall motion score index was significantly lower at follow‐up in the transplantation (P = 0.04) but not in the control group. On stress echocardiography, there was improvement of myocardial contractility in one or more previously nonviable myocardial segments in 5 out of 11 patients (all with recent infarctions) and in none of the controls (P = 0.01). Restoration of uptake of Tc99m sestamibi in one or more previously nonviable myocardial scars was seen in 6 out of 11 patients subjected to transplantation and in none of the controls (P = 0.02). Cell transplantation was an independent predictor of improvement of nonviable tissue. Intracoronary transplantation of MSCs and EPCs is feasible, safe, and may contribute to regional regeneration of myocardial tissue early or late following MI.

Plasma profiles of peripheral monocyte-related inflammatory markers in patients with arterial hypertension. Correlations with plasma endothelin-1.

BACKGROUND This study investigates the plasma activity of inflammatory mediators such as granulocyte-macrophage colony-stimulating factor (GM-CSF), C-C chemokines and soluble adhesion molecules, produced by monocyte-endothelial cell adhesive interaction, in patients with arterial hypertension. METHODS We studied 66 untreated patients with mild to moderate arterial hypertension (hypercholesterolemic: 34, normocholesterolemic: 32) and 30 sex- and age-matched normocholesterolemic normotensive controls. Plasma concentrations of GM-CSF, macrophage chemoattractant protein-1 (MCP-1), macrophage inflammatory protein-1alpha (MIP-1alpha), RANTES (regulated on activation normally T-cell expressed and secreted), soluble intercellular adhesion molecule-1 (sICAM-1) and soluble vascular cell adhesion molecule-1 (sVCAM-1), as well as plasma endothelin-1 (ET-1), were determined in study population by ELISA and RIA, respectively. RESULTS Hypertensives exhibited significantly higher levels of GM-CSF (6.5+/-1.3 vs. 2.3+/-0.7 pg/ml, P=0.099), MCP-1 (175+/-31 vs. 120+/-24 pg/ml, P=0.0093), MIP-1alpha (23+/-4 vs. 15+/-2 pg/ml, P=0.0089), RANTES (17+/-4 vs. 14+/-3 ng/ml, P=0.047), sICAM-1 (235+/-39 vs. 187+/-21 ng/ml, P=0.0041), sVCAM-1 (684+/-42 vs. 589+/-23 ng/ml, P=0.0045) and ET-1 (6.1+/-1.5 vs. 2.4+/-0.3 pg/ml, P=0.0095) than those of normotensives. The normocholesterolemic hypertensives had significantly lower levels of GM-CSF, MCP-1, MIP-1alpha, sICAM-1 and sVCAM-1 than hypercholesterolemic hypertensives but higher than normotensives. In hypertensives, ET-1 levels were significantly correlated with mean arterial pressure (r=0.51, P=0.028), MCP-1 values (r=0.45, P=0.047) and sICAM-1 levels (r=0.64, P=0.0090). Significant correlations were also found between LDL cholesterol values and plasma inflammatory factors GM-CSF (r=0.58, P=0.0088), MCP-1 (r=0.49, P=0.040) and sICAM-1 (r=0.53, P=0.034) in the hypercholesterolemic sub-group of hypertensives. CONCLUSIONS Inflammatory markers of monocyte-endothelial cell adhesive interaction are elevated in hypertensives in comparison to normotensives and may be related to plasma ET-1 activity. The coexistence of hypercholesterolemia may enhance this inflammatory process induced by arterial hypertension.

Association of Neutrophil Gelatinase-Associated Lipocalin With the Severity of Coronary Artery Disease

Serum neutrophil gelatinase-associated lipocalin (NGAL) concentrations were measured in 73 consecutive patients who underwent first-time angiography for suspected coronary artery disease (CAD), and their associations with angiographic indexes of the severity of CAD (i.e., number of diseased vessels and modified Gensini score) were estimated. Median serum NGAL levels in patients with angiographically confirmed CAD were significantly higher than those in patients with normal coronary arteries (29.0 ng/ml [interquartile range 25.2 to 36.8] vs 22.4 ng/ml [interquartile range 17.34 to 32.0], p = 0.004). Statistically significant correlations were observed between serum NGAL level and the number of diseased vessels (r(s) = 0.390, p = 0.01) and modified Gensini score (r(s) = 0.356, p = 0.002). Using multivariate analysis, serum NGAL level was independently associated with the presence and severity of CAD. In conclusion, serum NGAL levels are significantly higher in the presence of CAD and are correlated with the severity of the disease. Further clinical studies are needed to confirm the use of NGAL as a biomarker for the detection and extent of CAD.

Radiation exposure of patients and coronary arteries in the stent era: A prospective study

Previous studies have investigated the radiation dose to doctors and patients during coronary angiography and angioplasty, but most of them were retrospective, conducted in the prestent era, and results have not been consistent. Effective dose of 57 patients undergoing coronary angiography and/or angioplasty was assessed by using a dose‐area product (DAP) to effective dose conversion factor. Radiation exposure risks to patients were then calculated for each procedure. Thermoluminescent dosimeters, mounted on a specially designed catheter that was advanced to the left or right sinus of Valsalva, were used to measure the dose received by the coronary arteries. Mean effective dose received by patients were 5.0 ± 0.5 mSv for coronary angiography, 6.6 ± 1.0 mSv for angioplasty, 10.2 ± 1.5 mSv for angioplasty followed by stent implantation, 13.6 ± 2.5 mSv for angiography followed by ad hoc angioplasty, and 16.7 ± 2.8 mSv for angiography followed by ad hoc angioplasty and stent implantation. Patient risk of developing cancer after each procedure was 0.025%, 0.033%, 0.051%, 0.068%, and 0.084%, respectively. Corresponding mean coronary irradiation doses were 24 ± 2.5, 31.0 ± 3.6, 43.6 ± 7.2, 55.0 ± 7.5, and 64.7 ± 5.6 mGy, respectively. A linear relationship of the DAP and the dose at the coronary arteries was found: DAP = 1,273 (cm2) × coronary dose (mGy). Radiation exposure to coronary arteries and associated risk to patients are relatively low, even following complicated, multivessel angioplasty with stent implantation. Our method can be used for calculation of radiation risk to patients and radiation dose to coronary arteries by using external dosimeters. Cathet. Cardiovasc. Intervent. 51:259–264, 2000.

Medical personnel and patient dosimetry during coronary angiography and intervention.

Percutaneous coronary interventions are associated with increased radiation exposure compared to most radiological examinations. This prospective study aimed at (1) measuring entrance doses for all in-room personnel, (2) performing an assessment of patient effective dose and intracoronary doses, (3) investigating the contribution of each projection to kerma-area product (KAP) and irradiation time, (4) comparing results with established DRL values in this clinical setting and (5) estimating the risk for fatal cancer to patients and operators. Measurements were performed during 40 consecutive procedures of coronary angiography (CA), half of which were followed by ad hoc coronary angioplasty (PTCA). KAP measurements were used for patients and thermoluminescent dosimetry for the in-room personnel. The mean KAP value per procedure for CA was 29 +/- 9 Gy cm2. Thirty four per cent of KAP was due to fluoroscopy, whereas the remainder (66%) was due to digital cine. Accordingly, the mean KAP value per PTCA procedure was 75 +/- 30 Gy cm2, and contribution of fluoroscopy is 57%. Effective dose per year was estimated to be 0.04-0.05 mSv y(-1) for the primary operator, and 0.03-0.04 mSv y(-1) for those assisting. Corresponding measurements for radiographer and nurse were below detectable level, implying minimal radiation hazards for them. Regarding radiation exposure, coronary intervention is considered a quite safe procedure for both patients and personnel in laboratories with modern equipment and experienced operators as long as standard safety precautions are considered. Exposure optimization though should be constantly sought through continuous review of procedures.

Latent arterial hypertension in apparently lone atrial fibrillation.

Introduction. Longitudinal studies on lone AF are rare and the incidence of hypertension in this population unknown. This study aimed at investigating the incidence of arterial hypertension in patients with apparently lone atrial fibrillation (AF).Methods and Results. Out of 292 consecutive patients presented with permanent or paroxysmal AF, 32 patients were diagnosed as having lone AF according to strict criteria. Three patients were subjected to ablation of the ligament of Marshall, 14 patients to pulmonary vein isolation, and the remainder were treated with beta blockade. Patients were followed-up for a 1–3 year period. During follow-up, 14 patients were diagnosed as having arterial hypertension. Thirteen of them had recurrent AF despite ligament of Marshall ablation (1 patient), pulmonary vein isolation (4 patients) and beta blockade (8 patients). Cox regression analysis revealed that the only significant predictor of development of hypertension was complete or partial response to antiarrhythmic therapy (beta = 3.82, S.E. = 1.22, exp(b) = 45.63, 95% C.I. = 4.17–499.2, p = 0.001), independent of age (beta = −0.01, p = 0.74), sex (beta = −0.91, p = 0.28), left ventricular ejection fraction (beta = 0.06, p = 0.52), left atrial size (beta = 0.58, p = 0.7) and kind of antiarrhythmic therapy (ablation or drug therapy) (beta = 1.36, p = 0.09). In patients with lone AF that did not respond at all to antiarrhythmic therapy, there was a 45.6 times higher risk of diagnosing hypertension during the next 3 years as compared to responders.Conclusion. Approximately 44% of patients with an initial diagnosis of lone AF may represent occult cases of arterial hypertension. In these patients hypertension may affect AF recurrence and treatment outcomes, regardless of the mode of antiarrhythmic therapy used.

Clinical and angiographic characteristics of patients with coronary artery ectasia

BACKGROUND The relationship of the extent of coronary artery ectasia (CAE) with coronary blood flow in the major epicardial arteries has not been adequately assessed. This study aimed at investigating the association of the topographical extent of CAE with coronary flow velocity and clinical characteristics in patients with isolated CAE and in patients with coexisting obstructive coronary artery disease (CAD). METHODS We reviewed 3764 consecutive coronary angiograms performed at Athens Euroclinic and identified patients with CAE according to standard criteria. The topographical extent of ectasia was considered, and coronary flow velocity was determined using the TIMI frame count (TFC). The severity of CAD was assessed using the modified Gensini index and the number of diseased vessels. Clinical data were correlated with TFC and CAD severity analysis. RESULTS Ectatic lesions were identified in 119 patients. The mean TFC correlated positively with the topographical extent of CAE (rs=0.733, p<0.001). Stepwise multiple linear regression revealed that the topographical extent of CAE and the maximum diameter of the ectatic segment in the corresponding artery are independent predictors of TFC in LAD and RCA. Using multivariate analysis, a history of myocardial infarction was independently associated with CAE extent, and CAD severity. CONCLUSIONS The extent of ectasia in the coronary vasculature is correlated with coronary flow velocity and associated with clinical presentation independent of coexisting significant coronary stenoses.

Comparison of the transseptal approach to the transaortic approach for ablation of Left-Sided accessory pathways in patients with Wolff-Parkinson-White syndrome

Forty-four consecutive patients with Wolff-Parkinson-White syndrome and a left-sided accessory pathway were randomized to either a single-catheter transaortic or a single-catheter transseptal approach. The transseptal approach resulted in decreased procedural duration, radiation exposure, and radiofrequency lesions compared with the transaortic technique.

Anatomic Characteristics of Culprit Sites in Acute Coronary Syndromes

BACKGROUND A detailed analysis of the anatomic relationships of the site of culprit lesions that have resulted in acute coronary syndromes (ACS) has not been reported. METHODS Coronary angiograms of consecutive patients who presented with ACS were analyzed according to multiple anatomic criteria. RESULTS In left anterior descending artery (LAD) (n = 85), 85% of culprit lesions were located in the first 40 mm from the ostium. The presence of angulation on the lesion increased the risk of an ACS 1.92 times (95% confidence interval [CI] 1.9-3.07), and the presence of bifurcation after the lesion increased the risk 1.65 times (95% CI 1.04-2.62). Angulated lesions located within the first 40 mm from the ostium and before a bifurcation presented an 11-fold increased risk for an ACS. In right coronary artery (RCA) (n = 58), the risk of plaque rupture was almost 2.5 times higher in lesions located between 10 and 50 mm from the ostium compared to those located in 90-130 mm (relative risk [RR] 2.38, 95% CI 1.25-4.56). In left circumflex (LCx) (n = 40), the risk of plaque rupture was almost 4.5 and 5 times higher in the first 20 mm, and between 20 and 40 mm from the ostium, respectively, compared to 60 and 80 mm (relative risk [RR] 4.58, 95% CI 1.01-20.68 for 0-20 mm, and RR 4.95, 95% CI 1.14-21.47 for 20-40 mm) after adjustment for the presence of curve on the lesion. The presence of lesion angulation increased the risk of plaque rupture almost three times (RR 3.22, 95% CI 1.49-6.93). CONCLUSION Specific anatomic features of the coronary arteries predispose to development and/or subsequent rupture of vulnerable plaques.

Staged circumferential and ostial pulmonary vein ablation for the treatment of paroxysmal atrial fibrillation.

Background: Comparisons between segmental ostial disconnection of the pulmonary veins (PV) and circumferential ablation have produced conflicting results in patients with paroxysmal atrial fibrillation (AF). The aim of this study was to evaluate a staged ablation procedure, every step of which was assessed by means of AF inducibility.