Effect of left ventricular pacing mode and site on hemodynamic, torsional and strain indices.

Introduction: Several reports have indicated that left ventricular (LV) lead placement at an optimal pacing site is an important determinant of short- and long-term outcome. This study investigated the effect of pacing mode (atrioventricular [AV] or ventricular) and site (LV apical or lateral) outside the ischemic region on the LV hemodynamic, torsional and strain indices in the ischemic myocardium.

Methods: Experiments were conducted in anesthetized open-chest pigs (n = 15) 30 min after LAD ligation to investigate the hemodynamic effects of temporary epicardial AV and ventricular LV pacing at the LV apical (outside the ischemic region) or lateral wall.

Atrioventricular left ventricular apical pacing improves haemodynamic, rotational, and deformation variables in comparison to pacing at the lateral wall in intact myocardium: experimental study.

Aim. To assess the effect on left ventricular (LV) function of atrioventricular (AV) and ventricular pacing at the LV apical or lateral wall and to compare the normal torsional and deformation pattern of the intact LV myocardium with those created by the aforementioned LV pacing modes and sites. Methods.

Apical rotation as an early indicator of left ventricular systolic dysfunction in acute anterior myocardial infarction: experimental study.

Introduction: The aim of this study was to determine whether left ventricular (LV) apical rotation assessed by speckle tracking echocardiography (STE) can predict global LV systolic dysfunction after acute anterior myocardial infarction (AMI).

Methods: STE analysis was applied to LV short-axis images at the basal and apical levels in 21 open-chest pigs, before and after left anterior descending coronary artery ligation. LV radial and circumferential strain and strain rate, apical and basal rotation, and LV torsion were recorded.

Transcatheter patch occlusion of the left atrial appendage using surgical adhesives in high-risk patients with atrial fibrillation.

Objectives: The efficacy of left atrial appendage (LAA) occlusion using the Transcatheter Patch (TP) (Custom Medical Devices, Athens, Greece) in conjunction with surgical adhesives was assessed.

Background: The TP is a bioabsorbable device that can be adjusted for the shape and size of the LAA without the risk of perforation. It is attached by a surgical adhesive and is released in 45 min.

Effect of dobutamine combined with intra-aortic balloon counterpulsation on left ventricular function early after acute myocardial infarction: experimental study.

Acute myocardial infarction (AMI) causes left ventricular (LV) remodeling, which forms the substrate for its early and late complications. The purpose of this study was to compare the acute effect of dobutamine or intra-aortic balloon pumping (IABP), alone or in combination, on LV function in the early phase of an experimental AMI. In 18 pigs, AMI was induced by ligation of the left anterior descending artery (LAD).

Intra-aortic balloon counterpulsation 50 years later: initial conception and consequent ideas.

For nearly 50 years, intra-aortic balloon counterpulsation (IABC) has been the most widely applied temporary assistance method, operating in series with the heart. It helps wean patients from the heart-lung machine after cardiac operations. It is also used in patients with advanced coronary heart disease before and during cardiac and noncardiac operations as well as during percutaneous interventions.

Myocardial performance index suggests optimal fluid loss during hemodialysis.

Background: Patients on long-term maintenance hemodialysis (HD) are at high risk of developing cardiovascular disease and suffering various cardiovascular complications during HD.

Hypothesis: The purpose of this study was to evaluate the influence of changing loading conditions on the myocardial performance index (MPI) in patients on long-term HD and to specify an optimal level of fluid loss during HD that would maintain stable global cardiac function.

Methods: The study consisted of 52 patients with end-stage renal failure (ESRF), mean age 56±11.

Effect of early changes in functional geometry of left ventricular contraction on the development of ventricular fibrillation during acute myocardial ischaemia. An experimental study.

Objective: The early appearance of ventricular fibrillation (VF) following acute myocardial infarction (MI) is associated with adrenergic effects and electrical interactions although some early "mechanical" changes may also occur. The aim of the present experimental study was to examine whether early changes in the functional geometry of left ventricular (LV) contraction may be associated with ventricular arrhythmias occurring during the first 120min of MI.

Methods: In 11 swine left anterior descending (LAD) coronary artery ligation was performed.

Pacing within the ischemic area significantly decreases the left ventricular ejection fraction during experimental acute myocardial infarction.

Background: The aim of this study was to examine the effects on left ventricular (LV) function of LV apical or/and lateral wall pacing during an experimental acute myocardial infarction.

Methods: In 12 anesthetized pigs, epicardial LV pacing at the apex or lateral wall, or at both sites simultaneously, was performed before and after left anterior descending (LAD) ligation. Data concerning LV function were obtained by two-dimensional echo during spontaneous sinus rhythm (SR) and during pacing before and 15, 45, 60, and 90 minutes after LAD ligation.

The effect of open-chest cardiac resuscitation on mitral regurgitant flow: an on-line transesophageal echocardiographic study in dogs.

Introduction: We sought to determine the effect of cardiac massage on a pre-existing regurgitant mitral valve during open-chest cardiopulmonary resuscitation (OCCPR) in an animal experiment.

Methods: Our study included 29 dogs that were used as experimental models. We anesthetized them and inserted a transesophageal echocardiographic (TEE) probe.

Transesophageal atrial pacing stress echocardiography: difficulties in the performance and the interpretation of the test.

Introduction: Transesophageal atrial pacing stress echocardiography (TEAPSE) has been proposed as an alternative stress echo test in selected patients with known or suspected coronary artery disease. The purpose of this study was to determine: (1) whether TEAPSE could serve as a suitable provocative stress test in patients with stroke and (2) to investigate whether the pseudohypertrophy during TEAPSE that has been observed in experimental studies is also seen in the clinical setting.

Methods: TEAPSE at increasing heart rates was performed in 29 patients with stroke.

Diurnal correlation of ambulatory blood pressure and interstitial glucose in patients with normal glucose tolerance.

Objective: Among the physiological variables whose diurnal profile is governed by circadian rhythmicity, plasma glucose concentrations, and arterial blood pressure constitute key elements of the physiological regulation of energy homeostasis. Evidence on their diurnal association derived from frequent measurements of both variables is, however, lacking in humans.

Methods: We investigated the relationship between blood pressure levels recorded by an ambulatory device and interstitial glucose concentrations on an outpatient basis, in patients with normal glucose tolerance (N=20), either normotensive (group A; N=10), or newly diagnosed with essential hypertension (group B; N=10).

Preservation of coronary sinus flow after complete ligation of all coronary arteries.

Introduction: The contribution of the collateral network to myocardial oxygenation under normal circumstances is not clear. However, it is possible that in diseased myocardium this network may be activated and contributes significantly to cardiac blood supply. The purpose of this study was to examine the coronary sinus flow after acute, synchronous, complete occlusion of all epicardial coronary arteries and to investigate methods to increase the flow in the setting of ischaemia.

Effect of dobutamine on left ventricular functional geometry after acute myocardial infarction: experimental study.

Introduction: Acute myocardial infarction causes left ventricular (LV) remodelling, which forms the substrate for its early and late complications. The aim of this experimental study was to evaluate the acute changes in LV functional geometry after acute myocardial infarction using echocardiography and to investigate the effect of continuous intravenous dobutamine administration on those changes.

Methods: In 22 pigs acute myocardial infarction was induced by ligation of the anterior descending branch of the left coronary artery.

Impact of the time rate of blood pressure variation on left ventricular mass.

Objectives: Blood pressure (BP) changes are steeper in hypertensive than in normotensive individuals, whereas an increased rate of BP fluctuations is associated with medial hypertrophy of the carotid arteries. We evaluated the association between the rate of BP variation derived from ambulatory blood pressure monitoring (ABPM) data analysis and left ventricular mass (LVM).

Methods: ABPM and echocardiographic measurements of LVM were performed in 365 normotensive, 185 white-coat hypertensive (WCH) and 448 uncomplicated hypertensive individuals.

Twenty-four-hour heart rate and blood pressure are additive markers of left ventricular mass in hypertensive subjects.

Background: We investigated whether mean heart rate (HR(24)) and blood pressure (BP) parameters during 24-h ambulatory BP monitoring (ABP) are independent or additive markers of left ventricular (LV) mass in subjects with newly diagnosed, untreated hypertension.

Methods: A total of 250 patients (40% women, 60% men; mean age 59.6 +/- 11 years) with essential hypertension who were attending the outpatient Hypertension Unit were studied.

Primary prevention of arterial thromboembolism in the oldest old with atrial fibrillation--a randomized pilot trial comparing adjusted-dose and fixed low-dose coumadin with aspirin.

Background: Anticoagulation therapy remains largely underused in older people with atrial fibrillation (AF). The aim of this pilot trial was to investigate the effects of low-intensity adjusted-dose and fixed-dose coumadin on the incidence of arterial thromboembolism and bleeding, as well as the efficacy of anticoagulation monitoring in elderly AF patients.

Methods: In this open-label, randomized trial we recruited patients over 75 years of age without previous stroke or systemic embolism.

Anticoagulation influences long-term outcome in patients with nonvalvular atrial fibrillation and severe ischemic stroke.

Background: Limited data exist regarding long-term prognosis in patients with nonvalvular atrial fibrillation (AF) who have survived a severe, disabling stroke.

Objective: The aim of this study was to assess long-term prognosis and its determinants in a prospective case series of stroke survivors with AF and moderate to severe handicap.

Methods: From a consecutive series of AF patients with first-ever ischemic stroke, we evaluated prospectively those with moderate to severe disability (grade 4-5 on the modified Rankin Scale) who were treated during a 5-year follow-up period with either warfarin or aspirin.

Time rate of blood pressure variation is associated with increased common carotid artery intima-media thickness.

The extent of target-organ damage has been positively associated with the magnitude of blood pressure (BP) variability in essential hypertension. However, the clinical implications of the rate of BP changes have never been investigated. We evaluated the association between the rate of systolic BP (SBP) variation derived from ambulatory BP monitoring (ABPM) data analysis and the extent of common carotid artery (CCA) intima-media thickness (IMT) in normotensive (n=280) and in uncomplicated hypertensive subjects (n=234).

Pulse pressure and left ventricular diastolic dysfunction in hypertensive patients.

Background: Impaired left ventricular diastolic function is a common finding in essential hypertension.

Methods: In order to investigate possible relationships between flow velocity through the mitral valve (E/A; index of left ventricular diastolic function) and 24-hour blood pressure and heart rate variations, 198 patients with mild to moderate essential hypertension were studied by Doppler echocardiography and ambulatory blood pressure monitoring. They were divided according to age into group 1 (n = 88, age 40-54 years) and group 2 (n = 110, age 55-79 years).