George Karatasakis - Academia.edu (original) (raw)
Papers by George Karatasakis
European Journal of Echocardiography, 2008
Complications of any mechanical prosthesis include thrombus or pannus formation. In our case repo... more Complications of any mechanical prosthesis include thrombus or pannus formation. In our case report we demonstrate that prosthetic aortic valve regurgitation due to pannus formation may be intermittent and non-cyclic in pattern and therefore not obvious at the time of original clinical examination. Under these conditions and as transesophageal echocardiography cannot be repeated promptly, transthoracic 2-D and Doppler echocardiography should
European Journal of Echocardiography, 2008
Aim: We tested the hypothesis that shortening of diastolic pressure half time (PHT) of left anter... more Aim: We tested the hypothesis that shortening of diastolic pressure half time (PHT) of left anterior descending (LAD) coronary flow in patients with old reperfused anterior myocardial infarction (MI) is related to the presence of permanent myocardial damage of the reperfused area. Methods and results: We studied 49 patients divided into: group A: 15 patients with previous anterior MI and
European Journal of Echocardiography, 2006
Results: A total of 93 echocardiograms were of diagnostic quality. Of these, 6 patients had LVSD.... more Results: A total of 93 echocardiograms were of diagnostic quality. Of these, 6 patients had LVSD. The R-pBNP assay correctly identified all cases of LVSD (sensitivity 100%; specificity 49%; positive predictive value (PPV) 12%; negative predictive value (NPV) 100%). Both BC-BNP&BT-BNP assays failed to predict one case of LVSD; (sensitivity 83%; specificity 79%; PPV 22%; NPV 98.5%) and (sensitivity 83%; specificity 79%; PPV 22%; NPV 98.5%) respectively. Direct inter-BNP assay correlation was good (R squared 0.735-0.887). Conclusion: Use of serum BNP assay on patients referred for suspected heart failure allows for accurate predictive reduction in the echocardiographic workload by 45.3% (R-pBNP) and 73.7% (BC-BNP&BT-BNP) respectively. This equated to a cost reduction per 100 referrals for echocardiography of 1320.50 for R-pBNP and 3313.20 for BC-BNP and BT-BNP.
European Journal of Echocardiography, 2003
Background: Detection of viability in myocardium that contracts poorly due to recurrent ischaemia... more Background: Detection of viability in myocardium that contracts poorly due to recurrent ischaemia is clinically important because hypokinetic or akinetic segments may recover function if treated promptly by revascularisation. Experiments suggest that non-invasive diagnosis may be possible using tissue Doppler echocardiography (TDE). Myocardial velocity responses to dobutamine can indicate ischaemia in patients with normal resting function, but changes in regional deformation indices may be more specific to diagnose viability since they are less influenced by motion of adjacent segments. We studied which TDE parameters can quantify functional reserve before and after coronary bypass surgery (CABG). Methods: 23 patients (21 men) aged 61±10 years, who had multivessel coronary artery disease and poor left ventricular (LV) function (ejection fraction (EF) <35% on Technetium 99 blood pool scan) underwent graded dobutamine stress echocardiography, and also nitrate-enhanced rest-redistribution Thallium 201 perfusion imaging, both before and 6 months after CABG. TDE parameters were analysed off-line in basal, mid-wall and apical segments, imaged from the apex (SPEQLE, University of Leuven). Perfusion images were analysed and scored from polar plots scaled to 100%, using a 16-segment model with a cut-off of 50%.
European Journal of Echocardiography, 2003
European Journal of Echocardiography, 2003
Archives of Hellenic Medicine
A 77-year-old man with an unremarkable past medical history, presented to the emergency departmen... more A 77-year-old man with an unremarkable past medical history, presented to the emergency department with palpitations of a few days duration. The patient was hemodynamically stable and afebrile. The 12-lead surface ECG is depicted in .
World journal of clinical cases, Jan 16, 2014
Left ventricular wall rupture (LVWR) comprises a complication of acute myocardial infarction (AMI... more Left ventricular wall rupture (LVWR) comprises a complication of acute myocardial infarction (AMI). Acute LVWR is a fatal condition, unless the formation of a pseudoaneurysm occurs. Several risk factors have been described, predisposing to LVWR. High index of suspicion and imaging techniques, namely echocardiography and computed tomography, are the cornerstones of timely diagnosis of the condition. As LVWR usually leads to death, emergency surgery is the treatment of choice, resulting in significant reduction in mortality and providing favorable short-term outcomes and adequate prognosis during late follow-up. Herein, we present two patients who were diagnosed with LVWR following AMI, and subsequent pseudoaneurysm formation. In parallel, we review the aforementioned condition.
European Heart Journal – Cardiovascular Imaging
Introduction: Our hypothesis is that structural abnormalities and functional impairment of the LA... more Introduction: Our hypothesis is that structural abnormalities and functional impairment of the LA in patients with atrial fibrillation (AF), are related to the probability of successful cardioversion and maintenance of sinus rhythm (SR). Purpose: To prove our hypothesis atrial volumetric indices, longitudinal 2D speckle tracking atrial parameters, and left atrial appendage emptying velocity (LAAV) have been correlated and used to predict cardioversion outcome and maintenance of SR in patients with chronic AF. Methods: In 23 patients (12 males, aged 64 ± 13 years) who had complete 2D transthoracic (TTE), Doppler and transesophageal (TEE) study prior to cardioversion, we measured by TTE maximum LA volume prior to mitral opening (LA max), minimum LA volume at mitral closure (LAmin) and calculated LA ejection fraction (LAEF) as LAmax-LAmin/LAmax %. LAAV was measured by TEE. For 2D speckle tracking of global longitudinal strain (LAGS) and strain rate (StR) measurement, we performed manua...
European Journal of Echocardiography, 2007
We tested the hypothesis that shortening of diastolic pressure half time (PHT) of left anterior d... more We tested the hypothesis that shortening of diastolic pressure half time (PHT) of left anterior descending (LAD) coronary flow in patients with old reperfused anterior myocardial infarction (MI) is related to the presence of permanent myocardial damage of the reperfused area. We studied 49 patients divided into: group A: 15 patients with previous anterior MI and evidence of myocardial scar; group B: 10 patients with previous anterior MI and no evidence of myocardial scar and group C: 24 patients without anterior MI. All patients underwent coronary angiography at least 6 months after an index event and any reperfusion procedure. Group A patients had lower PHT (199 +/- 62 ms) than group C (377 +/- 103 ms, p = 0.0001) and group B (316 +/- 154 ms, p = 0.029) patients. No other LAD flow velocity parameter differed among the 3 groups. A PHT value of 265 ms discriminated patients with scarred anterior wall with a sensitivity of 79% and a specificity of 94% (0.88, p &amp;amp;amp;lt; 0.001). Shortening of the LAD flow diastolic PHT in patients with remote, reperfused anterior MI reflects scarred myocardial tissue in the anteroapical wall while patients who maintain diastolic wall thickness after an acute coronary syndrome have PHT similar to patients without anterior MI.
The Journal of heart valve disease, 2013
Paravalvular leak (PVL) represents a potential complication of valve replacement surgery. The ... more Paravalvular leak (PVL) represents a potential complication of valve replacement surgery. The 'gold standard' treatment for patients with severe prosthetic dysfunction, hemolysis or symptoms, is surgery. Reoperative valve surgery for such patients is related to high morbidity and mortality rate. The percutaneous closure of PVL is feasible and safe, when performed at experienced interventional cardiologic centers. Herein, the case is reported of a patient who showed a significant improvement in left ventricular systolic function after transcatheter closure of an aortic prosthetic PVL with an Amplatzer duct occluder II (ADO II). A review of the current literature is also provided.
European journal of echocardiography : the journal of the Working Group on Echocardiography of the European Society of Cardiology, 2007
Dobutamine stress echocardiography is a commonly used imaging modality for the diagnosis of coron... more Dobutamine stress echocardiography is a commonly used imaging modality for the diagnosis of coronary artery disease and the detection of myocardial viability. The major limitations are that it is operator dependent and that the analysis is subjective and qualitative resulting in interobserver variability. It is also tedious and time consuming. Consequently, several quantitative approaches have been proposed, such as acoustic quantification and color kinesis but none of these has proved to be fully quantitative. In this manuscript we describe the development of a new, quantitative technique based on tracking of both endocardium and epicardium providing information of endocardial excursion and myocardial thickening, a crucial parameter of wall function evaluation. Preliminary data indicate that the method is practical and feasible, but clinical trials are required to prove whether it will improve the sensitivity and specificity of dobutamine stress echocardiography.
European journal of echocardiography : the journal of the Working Group on Echocardiography of the European Society of Cardiology, 2008
Complications of any mechanical prosthesis include thrombus or pannus formation. In our case repo... more Complications of any mechanical prosthesis include thrombus or pannus formation. In our case report we demonstrate that prosthetic aortic valve regurgitation due to pannus formation may be intermittent and non-cyclic in pattern and therefore not obvious at the time of original clinical examination. Under these conditions and as transesophageal echocardiography cannot be repeated promptly, transthoracic 2-D and Doppler echocardiography should be available at any time when symptoms occur and present the method of choice for acute patient evaluation. Thrombolysis seems to be the first treatment of choice in case of thrombus formation and re-do surgery in case of pannus formation.
Heart (British Cardiac Society), 2003
To measure the distance between the mitral leaflet coaptation point and the mitral annulus (CPMA)... more To measure the distance between the mitral leaflet coaptation point and the mitral annulus (CPMA) and assess the relation of this index to structural and functional characteristics of the failing left ventricle. Echocardiographic indices and CPMA were measured at baseline and again during dobutamine infusion and leg lifting. Left ventricular diastolic and systolic dimensions, left ventricular ejection fraction (LVEF) by Simpson's rule, mitral annulus dimension, and E point septal separation were correlated with CPMA. Tertiary referral centre. The total study population of 129 patients included 94 with LVEF < 35% and 35 with LVEF 35%-45%; 76 had coronary artery disease and 53 had dilated cardiomyopathy. A dobutamine infusion was given in 18 patients and preload increase by leg lifting in 28. Correlations between CPMA and contractility indices at baseline and during interventions. CPMA was correlated with left ventricular diastolic dimension (r = 0.52), left ventricular systoli...
European Journal of Echocardiography, 2010
We sought to evaluate the efficacy of intracoronary infusion of selected bone marrow stem cells (... more We sought to evaluate the efficacy of intracoronary infusion of selected bone marrow stem cells (BMSCs) in patients with remote, anterior non-viable MI by the use of tissue Doppler imaging. We infused selected CD133+ and CD133-CD34+ BMSCs in 10 patients enrolled in the study. Peak systolic strain rate, maximum strain during the cardiac cycle (epsilon(max)), strain during ejection time (epsilon(et)), and post-systolic strain (epsilon(ps)) were measured. Peak systolic strain rate (-0.69 +/- 0.2 vs. -1.15 +/- 0.27, P = 0.001), epsilon(max) (-9.87 +/- 3.30 vs. -15.57 +/- 5, P = 0.006), and epsilon(et) (-7.45+/-2.86 vs. -10.92 +/- 4.45, P = 0.015) improved significantly during the rest study 6 months after cell infusion. Low-dose inotropic challenge also showed significant improvement of longitudinal deformation indices in the follow-up study. Global ejection fraction did not improve significantly after cell therapy. Intracoronary infusion of selected BMSCs in patients with remote, anterior, non-viable myocardial infarction is safe and leads to improvement of longitudinal deformation indices 6 months after the infusion.
EuroIntervention, 2007
Percutaneous implantation of a large stent was performed in the coronary sinus of pigs, to assess... more Percutaneous implantation of a large stent was performed in the coronary sinus of pigs, to assess safety and immediate efficacy for reduction of acute ischaemic mitral regurgitation. Acute ischaemic mitral regurgitation (MR) was produced in seven pigs, continuously monitored with echocardiography, during repeated balloon inflations in the proximal left circumflex artery. The protocol was repeated following placement of a stent in the coronary sinus. Five pigs survived the period of acute ischaemia and developed severe mitral regurgitation (&amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;/=3+/4+). Following successful stent implantation, the MR area decreased from 2.4+/-0.4 cm2 to 1.1+/-0.6 cm2 (p=0.016) and the proximal isovelocity surface area (PISA) MR flow from 63.9+/-37.3 ml/sec to 44.0+/-35.0 ml/sec (p=0.029). Coronary sinus stent prevented the ischaemia-induced increase in septal-lateral mitral annulus dimension (p=0.041) and left ventricular dilatation. Three animals were allowed to recover and underwent histological analysis of the coronary sinus stent at 30 days, showing endothelialisation and minimal hyperplasia, without thrombus formation. A percutaneously deployed stent in the coronary sinus may help to decrease the severity of acute ischaemic mitral regurgitation.
Canadian Journal of Cardiology, 2014
Left atrial (LA) stunning, the transient impairment of LA function, is responsible for an increas... more Left atrial (LA) stunning, the transient impairment of LA function, is responsible for an increased thrombo-embolic risk after cardioversion of atrial fibrillation (AF). Angiotensin receptor blockers (ARBs) attenuate atrial remodelling in AF and could theoretically influence LA stunning. We studied the effect of Irbesartan on LA stunning. We prospectively assigned 50 patients from the outpatient clinic undergoing electrical cardioversion for AF with duration of &amp;amp;amp;amp;amp;amp;amp;gt;4 weeks, into two matched groups: 25 patients were treated with Irbesartan (228+/-93 mg/day) for at least 2 weeks prior to cardioversion (Irbesartan group); 25 patients did not receive ARBs (control group). The groups did not differ concerning age (64+/-13 vs. 63+/-13 years, respectively), AF duration (20+/-18 vs. 20+/-19 weeks), underlying disease, LA diameter (46+/-7 vs. 47+/-9 mm), left ventricular dimensions, and ejection fraction (47.7+/-11.6 vs. 49.7+/-14.5%). We assessed LA appendage emptying velocities (LAAEV) and LA spontaneous echo contrast (LASEC) by transoesophageal echocardiography before and after cardioversion and at 2 weeks, and the A-wave by transthoracic echocardiography after cardioversion, at 2 and at 4 weeks. LA stunning was significantly attenuated in the Irbesartan group. The reduction of LAAEV immediately after cardioversion was significantly less in the Irbesartan group (LAAEV reduction of 9+/-49% from 28+/-9 cm/s before cardioversion to 25+/-13 cm/s immediately afterwards) than in the control group (reduction of 48+/-20% from 34+/-15 cm/s before cardioversion to 16+/-6 cm/s afterwards) (P = 0.048). New or increased LASEC occurred in eight patients (32%) in the Irbesartan vs. 16 patients (64%) in the control group (P = 0.046). Irbesartan significantly attenuates LA stunning after electrical cardioversion of AF. Therefore, ARBs may represent an important pharmacological supplementation in patients being prepared for cardioversion.
European Journal of Echocardiography, 2003
European Journal of Echocardiography, 1999
European Journal of Echocardiography, 2008
Complications of any mechanical prosthesis include thrombus or pannus formation. In our case repo... more Complications of any mechanical prosthesis include thrombus or pannus formation. In our case report we demonstrate that prosthetic aortic valve regurgitation due to pannus formation may be intermittent and non-cyclic in pattern and therefore not obvious at the time of original clinical examination. Under these conditions and as transesophageal echocardiography cannot be repeated promptly, transthoracic 2-D and Doppler echocardiography should
European Journal of Echocardiography, 2008
Aim: We tested the hypothesis that shortening of diastolic pressure half time (PHT) of left anter... more Aim: We tested the hypothesis that shortening of diastolic pressure half time (PHT) of left anterior descending (LAD) coronary flow in patients with old reperfused anterior myocardial infarction (MI) is related to the presence of permanent myocardial damage of the reperfused area. Methods and results: We studied 49 patients divided into: group A: 15 patients with previous anterior MI and
European Journal of Echocardiography, 2006
Results: A total of 93 echocardiograms were of diagnostic quality. Of these, 6 patients had LVSD.... more Results: A total of 93 echocardiograms were of diagnostic quality. Of these, 6 patients had LVSD. The R-pBNP assay correctly identified all cases of LVSD (sensitivity 100%; specificity 49%; positive predictive value (PPV) 12%; negative predictive value (NPV) 100%). Both BC-BNP&BT-BNP assays failed to predict one case of LVSD; (sensitivity 83%; specificity 79%; PPV 22%; NPV 98.5%) and (sensitivity 83%; specificity 79%; PPV 22%; NPV 98.5%) respectively. Direct inter-BNP assay correlation was good (R squared 0.735-0.887). Conclusion: Use of serum BNP assay on patients referred for suspected heart failure allows for accurate predictive reduction in the echocardiographic workload by 45.3% (R-pBNP) and 73.7% (BC-BNP&BT-BNP) respectively. This equated to a cost reduction per 100 referrals for echocardiography of 1320.50 for R-pBNP and 3313.20 for BC-BNP and BT-BNP.
European Journal of Echocardiography, 2003
Background: Detection of viability in myocardium that contracts poorly due to recurrent ischaemia... more Background: Detection of viability in myocardium that contracts poorly due to recurrent ischaemia is clinically important because hypokinetic or akinetic segments may recover function if treated promptly by revascularisation. Experiments suggest that non-invasive diagnosis may be possible using tissue Doppler echocardiography (TDE). Myocardial velocity responses to dobutamine can indicate ischaemia in patients with normal resting function, but changes in regional deformation indices may be more specific to diagnose viability since they are less influenced by motion of adjacent segments. We studied which TDE parameters can quantify functional reserve before and after coronary bypass surgery (CABG). Methods: 23 patients (21 men) aged 61±10 years, who had multivessel coronary artery disease and poor left ventricular (LV) function (ejection fraction (EF) <35% on Technetium 99 blood pool scan) underwent graded dobutamine stress echocardiography, and also nitrate-enhanced rest-redistribution Thallium 201 perfusion imaging, both before and 6 months after CABG. TDE parameters were analysed off-line in basal, mid-wall and apical segments, imaged from the apex (SPEQLE, University of Leuven). Perfusion images were analysed and scored from polar plots scaled to 100%, using a 16-segment model with a cut-off of 50%.
European Journal of Echocardiography, 2003
European Journal of Echocardiography, 2003
Archives of Hellenic Medicine
A 77-year-old man with an unremarkable past medical history, presented to the emergency departmen... more A 77-year-old man with an unremarkable past medical history, presented to the emergency department with palpitations of a few days duration. The patient was hemodynamically stable and afebrile. The 12-lead surface ECG is depicted in .
World journal of clinical cases, Jan 16, 2014
Left ventricular wall rupture (LVWR) comprises a complication of acute myocardial infarction (AMI... more Left ventricular wall rupture (LVWR) comprises a complication of acute myocardial infarction (AMI). Acute LVWR is a fatal condition, unless the formation of a pseudoaneurysm occurs. Several risk factors have been described, predisposing to LVWR. High index of suspicion and imaging techniques, namely echocardiography and computed tomography, are the cornerstones of timely diagnosis of the condition. As LVWR usually leads to death, emergency surgery is the treatment of choice, resulting in significant reduction in mortality and providing favorable short-term outcomes and adequate prognosis during late follow-up. Herein, we present two patients who were diagnosed with LVWR following AMI, and subsequent pseudoaneurysm formation. In parallel, we review the aforementioned condition.
European Heart Journal – Cardiovascular Imaging
Introduction: Our hypothesis is that structural abnormalities and functional impairment of the LA... more Introduction: Our hypothesis is that structural abnormalities and functional impairment of the LA in patients with atrial fibrillation (AF), are related to the probability of successful cardioversion and maintenance of sinus rhythm (SR). Purpose: To prove our hypothesis atrial volumetric indices, longitudinal 2D speckle tracking atrial parameters, and left atrial appendage emptying velocity (LAAV) have been correlated and used to predict cardioversion outcome and maintenance of SR in patients with chronic AF. Methods: In 23 patients (12 males, aged 64 ± 13 years) who had complete 2D transthoracic (TTE), Doppler and transesophageal (TEE) study prior to cardioversion, we measured by TTE maximum LA volume prior to mitral opening (LA max), minimum LA volume at mitral closure (LAmin) and calculated LA ejection fraction (LAEF) as LAmax-LAmin/LAmax %. LAAV was measured by TEE. For 2D speckle tracking of global longitudinal strain (LAGS) and strain rate (StR) measurement, we performed manua...
European Journal of Echocardiography, 2007
We tested the hypothesis that shortening of diastolic pressure half time (PHT) of left anterior d... more We tested the hypothesis that shortening of diastolic pressure half time (PHT) of left anterior descending (LAD) coronary flow in patients with old reperfused anterior myocardial infarction (MI) is related to the presence of permanent myocardial damage of the reperfused area. We studied 49 patients divided into: group A: 15 patients with previous anterior MI and evidence of myocardial scar; group B: 10 patients with previous anterior MI and no evidence of myocardial scar and group C: 24 patients without anterior MI. All patients underwent coronary angiography at least 6 months after an index event and any reperfusion procedure. Group A patients had lower PHT (199 +/- 62 ms) than group C (377 +/- 103 ms, p = 0.0001) and group B (316 +/- 154 ms, p = 0.029) patients. No other LAD flow velocity parameter differed among the 3 groups. A PHT value of 265 ms discriminated patients with scarred anterior wall with a sensitivity of 79% and a specificity of 94% (0.88, p &amp;amp;amp;lt; 0.001). Shortening of the LAD flow diastolic PHT in patients with remote, reperfused anterior MI reflects scarred myocardial tissue in the anteroapical wall while patients who maintain diastolic wall thickness after an acute coronary syndrome have PHT similar to patients without anterior MI.
The Journal of heart valve disease, 2013
Paravalvular leak (PVL) represents a potential complication of valve replacement surgery. The ... more Paravalvular leak (PVL) represents a potential complication of valve replacement surgery. The 'gold standard' treatment for patients with severe prosthetic dysfunction, hemolysis or symptoms, is surgery. Reoperative valve surgery for such patients is related to high morbidity and mortality rate. The percutaneous closure of PVL is feasible and safe, when performed at experienced interventional cardiologic centers. Herein, the case is reported of a patient who showed a significant improvement in left ventricular systolic function after transcatheter closure of an aortic prosthetic PVL with an Amplatzer duct occluder II (ADO II). A review of the current literature is also provided.
European journal of echocardiography : the journal of the Working Group on Echocardiography of the European Society of Cardiology, 2007
Dobutamine stress echocardiography is a commonly used imaging modality for the diagnosis of coron... more Dobutamine stress echocardiography is a commonly used imaging modality for the diagnosis of coronary artery disease and the detection of myocardial viability. The major limitations are that it is operator dependent and that the analysis is subjective and qualitative resulting in interobserver variability. It is also tedious and time consuming. Consequently, several quantitative approaches have been proposed, such as acoustic quantification and color kinesis but none of these has proved to be fully quantitative. In this manuscript we describe the development of a new, quantitative technique based on tracking of both endocardium and epicardium providing information of endocardial excursion and myocardial thickening, a crucial parameter of wall function evaluation. Preliminary data indicate that the method is practical and feasible, but clinical trials are required to prove whether it will improve the sensitivity and specificity of dobutamine stress echocardiography.
European journal of echocardiography : the journal of the Working Group on Echocardiography of the European Society of Cardiology, 2008
Complications of any mechanical prosthesis include thrombus or pannus formation. In our case repo... more Complications of any mechanical prosthesis include thrombus or pannus formation. In our case report we demonstrate that prosthetic aortic valve regurgitation due to pannus formation may be intermittent and non-cyclic in pattern and therefore not obvious at the time of original clinical examination. Under these conditions and as transesophageal echocardiography cannot be repeated promptly, transthoracic 2-D and Doppler echocardiography should be available at any time when symptoms occur and present the method of choice for acute patient evaluation. Thrombolysis seems to be the first treatment of choice in case of thrombus formation and re-do surgery in case of pannus formation.
Heart (British Cardiac Society), 2003
To measure the distance between the mitral leaflet coaptation point and the mitral annulus (CPMA)... more To measure the distance between the mitral leaflet coaptation point and the mitral annulus (CPMA) and assess the relation of this index to structural and functional characteristics of the failing left ventricle. Echocardiographic indices and CPMA were measured at baseline and again during dobutamine infusion and leg lifting. Left ventricular diastolic and systolic dimensions, left ventricular ejection fraction (LVEF) by Simpson's rule, mitral annulus dimension, and E point septal separation were correlated with CPMA. Tertiary referral centre. The total study population of 129 patients included 94 with LVEF < 35% and 35 with LVEF 35%-45%; 76 had coronary artery disease and 53 had dilated cardiomyopathy. A dobutamine infusion was given in 18 patients and preload increase by leg lifting in 28. Correlations between CPMA and contractility indices at baseline and during interventions. CPMA was correlated with left ventricular diastolic dimension (r = 0.52), left ventricular systoli...
European Journal of Echocardiography, 2010
We sought to evaluate the efficacy of intracoronary infusion of selected bone marrow stem cells (... more We sought to evaluate the efficacy of intracoronary infusion of selected bone marrow stem cells (BMSCs) in patients with remote, anterior non-viable MI by the use of tissue Doppler imaging. We infused selected CD133+ and CD133-CD34+ BMSCs in 10 patients enrolled in the study. Peak systolic strain rate, maximum strain during the cardiac cycle (epsilon(max)), strain during ejection time (epsilon(et)), and post-systolic strain (epsilon(ps)) were measured. Peak systolic strain rate (-0.69 +/- 0.2 vs. -1.15 +/- 0.27, P = 0.001), epsilon(max) (-9.87 +/- 3.30 vs. -15.57 +/- 5, P = 0.006), and epsilon(et) (-7.45+/-2.86 vs. -10.92 +/- 4.45, P = 0.015) improved significantly during the rest study 6 months after cell infusion. Low-dose inotropic challenge also showed significant improvement of longitudinal deformation indices in the follow-up study. Global ejection fraction did not improve significantly after cell therapy. Intracoronary infusion of selected BMSCs in patients with remote, anterior, non-viable myocardial infarction is safe and leads to improvement of longitudinal deformation indices 6 months after the infusion.
EuroIntervention, 2007
Percutaneous implantation of a large stent was performed in the coronary sinus of pigs, to assess... more Percutaneous implantation of a large stent was performed in the coronary sinus of pigs, to assess safety and immediate efficacy for reduction of acute ischaemic mitral regurgitation. Acute ischaemic mitral regurgitation (MR) was produced in seven pigs, continuously monitored with echocardiography, during repeated balloon inflations in the proximal left circumflex artery. The protocol was repeated following placement of a stent in the coronary sinus. Five pigs survived the period of acute ischaemia and developed severe mitral regurgitation (&amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;/=3+/4+). Following successful stent implantation, the MR area decreased from 2.4+/-0.4 cm2 to 1.1+/-0.6 cm2 (p=0.016) and the proximal isovelocity surface area (PISA) MR flow from 63.9+/-37.3 ml/sec to 44.0+/-35.0 ml/sec (p=0.029). Coronary sinus stent prevented the ischaemia-induced increase in septal-lateral mitral annulus dimension (p=0.041) and left ventricular dilatation. Three animals were allowed to recover and underwent histological analysis of the coronary sinus stent at 30 days, showing endothelialisation and minimal hyperplasia, without thrombus formation. A percutaneously deployed stent in the coronary sinus may help to decrease the severity of acute ischaemic mitral regurgitation.
Canadian Journal of Cardiology, 2014
Left atrial (LA) stunning, the transient impairment of LA function, is responsible for an increas... more Left atrial (LA) stunning, the transient impairment of LA function, is responsible for an increased thrombo-embolic risk after cardioversion of atrial fibrillation (AF). Angiotensin receptor blockers (ARBs) attenuate atrial remodelling in AF and could theoretically influence LA stunning. We studied the effect of Irbesartan on LA stunning. We prospectively assigned 50 patients from the outpatient clinic undergoing electrical cardioversion for AF with duration of &amp;amp;amp;amp;amp;amp;amp;gt;4 weeks, into two matched groups: 25 patients were treated with Irbesartan (228+/-93 mg/day) for at least 2 weeks prior to cardioversion (Irbesartan group); 25 patients did not receive ARBs (control group). The groups did not differ concerning age (64+/-13 vs. 63+/-13 years, respectively), AF duration (20+/-18 vs. 20+/-19 weeks), underlying disease, LA diameter (46+/-7 vs. 47+/-9 mm), left ventricular dimensions, and ejection fraction (47.7+/-11.6 vs. 49.7+/-14.5%). We assessed LA appendage emptying velocities (LAAEV) and LA spontaneous echo contrast (LASEC) by transoesophageal echocardiography before and after cardioversion and at 2 weeks, and the A-wave by transthoracic echocardiography after cardioversion, at 2 and at 4 weeks. LA stunning was significantly attenuated in the Irbesartan group. The reduction of LAAEV immediately after cardioversion was significantly less in the Irbesartan group (LAAEV reduction of 9+/-49% from 28+/-9 cm/s before cardioversion to 25+/-13 cm/s immediately afterwards) than in the control group (reduction of 48+/-20% from 34+/-15 cm/s before cardioversion to 16+/-6 cm/s afterwards) (P = 0.048). New or increased LASEC occurred in eight patients (32%) in the Irbesartan vs. 16 patients (64%) in the control group (P = 0.046). Irbesartan significantly attenuates LA stunning after electrical cardioversion of AF. Therefore, ARBs may represent an important pharmacological supplementation in patients being prepared for cardioversion.
European Journal of Echocardiography, 2003
European Journal of Echocardiography, 1999