Study on process parameters and optimization of microencapsulation based on phase separation.

As surfactants are capable of influencing the droplet formation, our study primarily aims the investigation of the effect of a nonionic surfactant e.g. Polysorbate 80 on the formation of microspheres on the course of vibrating nozzle method with coacervation. The experiments also concern the impact of the different process parameters (e.g. vibration frequency, feed rate and voltage) on the shape and size distribution of microspheres characterized by laser diffraction size determination completed with particle image analysis. The calcium-alginate microspheres were processed using freeze-drying to ensure solid state with better drug carrier capability. Addition of isomalt was advantageous in the formation of freeze-dried microspheres at low alginate concentration, which was explained by micro-CT analysis of the constructed particle structure. The internal three-dimensional network of calcium alginate demonstrated a more cancellous architecture ameliorating the roundness of microparticles.

Differential sensitivity of TREK-1, TREK-2 and TRAAK background potassium channels to the polycationic dye ruthenium red.

BACKGROUND AND PURPOSE: Pharmacological separation of the background potassium currents of closely related K2P channels is a challenging problem. We previously demonstrated that ruthenium red (RR) inhibits TASK-3 (K2 P 9.1), but not TASK-1 (K2 P 3.1) channels. RR has been extensively used to distinguish between TASK currents in native cells. In the present study, we systematically investigate the RR sensitivity of a more comprehensive set of K2 P channels. EXPERIMENTAL APPROACH: K(+) currents were measured by two-electrode voltage clamp in Xenopus oocytes and by whole-cell patch clamp in mouse dorsal root ganglion (DRG) neurons. KEY RESULTS: RR differentiates between two closely related members of the TREK subfamily. TREK-2 (K2 P 10.1) proved to be highly sensitive to RR (IC50 = 0.2 µM), whereas TREK-1 (K2 P 2.1) was not affected by the compound. We identified aspartate 135 (D135) as the target of the inhibitor in mouse TREK-2c. D135 lines the wall of the extracellular ion pathway (EIP), a tunnel structure through the extracellular cap characteristic for K2 P channels. TREK-1 contains isoleucine in the corresponding position. The mutation of this isoleucine (I110D) rendered TREK-1 sensitive to RR. The third member of the TREK subfamily, TRAAK (K2 P 4.1) was more potently inhibited by ruthenium violet, a contaminant in some RR preparations, than by RR. DRG neurons predominantly express TREK-2 and RR-resistant TREK-1 and TRESK (K2 P 18.1) background K(+) channels. We detected the RR-sensitive leak K(+) current component in DRG neurons. CONCLUSIONS AND IMPLICATIONS: We propose that RR may be useful for distinguishing TREK-2 (K2P 10.1) from TREK-1 (K2P 2.1) and other RR-resistant K2 P channels in native cells.

Left atrial and left atrial appendage function in paroxysmal atrial fibrillation.

PURPOSE: In patients with paroxysmal atrial fibrillation (PAF) little information is available about left atrial (LA)function, and there is less information about LA appendage (LAA) function, and about their relations. METHODS AND RESULTS: 46 patients were selected for catheter ablation (CA) because of nonvalvular PAF.Transthoracic, tissue Doppler and transoesophageal echocardiography was performed before CA. LA volumes and volume index (LAVI) were calculated. LA function was assessed by LA filling fraction (LAFF), LA emptying fraction (LAEF), systolic fraction of pulmonary venous flow (PVSF) and late diastolic velocities of mitral annulus(Aa,, A5at) LAA function was assessed by peak LAA emptying flow velocity (PLAAEFV). Diastolic dysfunction(DD) was also assessed. Dilated LAVI in 32, LA dysfunction in 20, DD with elevated LV filling pressure in 19 patients was found. Aa,at and Aa,p correlated with LAFF (r:0.53; p<0.001 and r:0.43; p<0.05), LAEF (r:0.51;p<0.001 and r:0.63; p<0.001), PVSF (r:0.49; p<0.001 and r:0.46; p<0.005) and PLAAEFV (r:0.58; p<0.001 and r:0.45; p<0.01). CONCLUSIONS: In PAF patients Aa velocity is useful to assess LA function and correlates positively with other TTE derived LA functional parameters and LAA function by TEE derived PLAAEFV.

Effect of dam and sire genotypes on productive and carcass traits of rabbits.

The aim of the experiment was to study the effect of dam and sire genotypes on the production and slaughter performance of growing rabbits. The experiment was carried out at Kaposvár University. Pannon White (PW) and maternal line (M) does were inseminated with the sperm of PW, M, large body line (LB), terminal line of Hycole hybrid (H), or colored line (CL) bucks. The mature body size of the M, PW, and CL genotypes was medium. The mature body size of the LB and H genotypes was large. Only PW and LB rabbits were selected for carcass traits based on computer tomograph (CT) scanning data. The rabbits (n = 320) were weaned at the age of 5 wk and housed in a closed climate-controlled rabbitry in wire cages. Rabbits were fed ad libitum a commercial pellet. Rabbits were slaughtered at 78 d of age. Daily BW gain (5.7%, P < 0.001) and G:F (6.2%, P < 0.001) of the progeny of PW does were better than those of the progeny of the M does. The weight of the chilled carcass and body parts was greater for the progeny of the PW does (P < 0.001). The ratio of the hind part compared with the reference carcass was greater in the PW group (P < 0.001); however, the ratio of the fore part was greater in the M group (P < 0.05). Examining the effect of the genotype of the sires, the BW and daily BW gain were greater in groups H and LB, whereas the progeny of M and CL sires were inferior (P < 0.05). Body weights at 11 wk of age were H: 2,918 g, LB: 2,793 g, PW: 2,678 g, CL: 2,636 g, and M: 2,585 g (P < 0.001). Similar differences were found for daily feed intake (P < 0.05). The G:F differed (P < 0.05) significantly between groups H and CL. The weights of the chilled carcass and of the body parts were the greatest for the progeny of the H sires, and the smallest in the M group. The differences between the dressing out percentages of the groups were not significant. The ratio of the fore part was greater (P < 0.05) in groups LB, H, and CL, but the ratio of the middle part was not different. The ratio of hind part related to the reference carcass was largest in progeny of PW and least in LB and CL groups (P < 0.05). It was concluded that the production of growing rabbits was affected by the adult BW of their sires, but the carcass traits were influenced by their own adult BW and by the CT-based selection.

Cardiac actinomycosis in a patient presenting with acute cardiac tamponade and a mass mimicking pericardial tumour.

A case of pericardial actinomycosis mimicking a pericardial tumour is reported. After the appearance of non-specific subpleural pulmonary nodules, a 48 year old woman presented with fever and clinical signs of pericardial tamponade. Subxiphoid pericardiotomy yielded a culture negative fluid and inflammatory reactive histopathology in the pericardial biopsy specimen. Because of suspected infection cefamandole was administered for 10 days and the patient became afebrile. The pericardial effusion recurred with no clinical signs two weeks later. Steroid medication resulted in rapid regression of the pericardial effusion. Subsequent echocardiography controls showed a tumour-like pericardial mass, confirmed by cardiac magnetic imaging. Surgical exploration led to the final histological diagnosis of actinomycosis. After high dose and long term penicillin G treatment the patient recovered fully with no recurrence during two years' follow up.

The role of thrombolysis in the management of left-sided prosthetic valve thrombosis: a study of 85 cases diagnosed by transesophageal echocardiography.

BACKGROUND AND AIM OF THE STUDY: Treatment strategies of prosthetic valve thrombosis (PVT) are controversial. The aim of this study was to compare the efficacy and safety of thrombolysis, surgery and heparin therapy in patients with either obstructive or non-obstructive PVT. METHODS: Between 1993 and 2000, 85 episodes of PVT were found (82 in the mitral position, three in the aortic) in 59 patients (22 males, 37 females; mean age 53 years; range: 28-80 years) by multiplane transesophageal echocardiography (TEE). Obstructive PVT was defined as restricted leaflet (occluder) motion with increased gradient, even if thrombus was not seen by TEE; non-obstructive PVT was considered as normal leaflet motion, irrespective of the gradients. Thrombolysis was given in 43 episodes (streptokinase, n = 37) by standard dosage protocols, surgery was performed in 20, and i.v. heparin was used in 22. Recurrence rate was calculated in 26 survivors of successful thrombolysis based on six months to six years follow up. Treatment with thrombolysis and heparin was monitored using TEE. RESULTS: There were 54 cases of obstructive PVT and 31 cases of non-obstructive PVT. Anticoagulation was inadequate in 82% of cases. Thrombolysis was completely successful in 37 cases (86% success rate); in 27 of 32 patients with obstructive PVT (in both cases of aortic location), and in 10 of 11 non-obstructive PVT. Heparin was successful in only nine of 18 non-obstructive PVT, and in none of four obstructive cases. Nine patients died, all with obstructive PVT, and all but one were in NYHA class IV; two were treated by thrombolysis (5% mortality), six by surgery (30% mortality) and one with heparin (5% mortality). Complications of thrombolysis included two strokes and two transient ischemic attack episodes (9%), and bleeding in one case (2%). There were six complications due to heparin treatment: newly developed obstruction in five patients and stroke in one patient. Recurrence was diagnosed in eight episodes in six patients with obstructive PVT after successful thrombolysis (22%); rethrombolysis was successful in four of five cases. CONCLUSION: Thrombolysis was shown to be superior to surgery in obstructive PVT, especially in NYHA class IV patients. Severe complications of thrombolysis were noted only in the critically ill. As heparin treatment appeared ineffective and unsafe for the treatment of PVT, thrombolysis appeared to be the optimal therapeutic choice in this condition.

Hippocampal rhythm generation: gamma-related theta-frequency resonance in CA3 interneurons.

During different behavioral states different population activities are present in the hippocampal formation. These activities are not independent: sharp waves often occur together with high-frequency ripples, and gamma-frequency activity is usually superimposed on theta oscillations. There is both experimental and theoretical evidence supporting the notion that gamma oscillation is generated intrahippocampally, but there is no generally accepted view about the origin of theta waves. Precise timing of population bursts of pyramidal cells may be due to a synchronized external drive. Membrane potential oscillations recorded in the septum are unlikely to fulfill this purpose because they are not coherent enough. We investigated the prospects of an intrahippocampal mechanism supplying pyramidal cells with theta frequency periodic inhibition, by studying a model of a network of hippocampal inhibitory interneurons. As shown previously, interneulrons are capable of generating synchronized gamnma-requency action potential oscillations. Exciting the neurons by periodic current injection, the system could either be entrained in an oscillation with the frequency of the inducing current or exhibit in-phase periodic changes at the frequency of single cell (and network) activity. Simulations that used spatially inhomogeneous stimulus currents showed antiphase frequency changes across cells, which resulted in a periodic decrease in the synchrony of the network. As this periodic change in synchrony occurred in the theta frequency range, our network should be able to exhibit the theta-frequency weakening of inhibition of pyramidal cells, thus offering a possible mechanism for intrahippocampal theta generation.

[Evaluation of myocardial perfusion using intravenous contrast echocardiography]. / Myocardialis perfúzió értékelése intravénás kontraszt-echokardiográfia segítségével.

The aim of the study was to assess the accuracy of rest myocardial contrast echocardiography (MCE) in detecting perfusion abnormalities after intravenous contrast administration in chronic coronary artery disease. In 21 patients (mean age 49 years) contrast agent was injected intravenously. ATL HDI 5000 ultrasound machine was used. Triggering every fifth cardiac cycle in end-systole apical 2-chamber, 3-chamber and 4-chamber views were used. All patients underwent thallium scintigraphy on the same day and coronary angiography was performed within 24 hours. Second harmonic imaging and power Doppler were used in assessing presence or absence of perfusion, localization and extent of perfusion defects, and their relation with wall motion. In the first group all the 13 patients after myocardial infarction had akinetic segments on echocardiography in accordance with the coronary occlusion detected by coronary angiography. In the second group none of the 8 patients without previous myocardial infarction had wall motion abnormality. Group I: dividing the left ventricle into 16 segments out of 208 segments 44 were akinetic. Perfusion defect was detected by MCE in 29 segments. In 12 segments with wall motion abnormality the normal myocardial perfusion was consistent with viable myocardium, 2 inferior akinetic segments could not be evaluated due to contrast attenuation and in one inferior segment MCE in contrast to the thallium scintigraphy showed no perfusion defect. Group II: good contrast effect was detected in all 128 segments except one inferior segment in which there was a fixed perfusion defect also by thallium scintigraphy and coronary angiography revealed occluded right coronary artery. In conclusion MCE and second harmonic triggered imaging is comparable with thallium scintigraphy in detecting fixed perfusion abnormalities. MCE may contribute to the detection of viable myocardium.

Measurement of left ventricular volumes and ejection fraction after intravenous contrast agent administration using standard echocardiographic equipment.

The enhancement of endocardial border delineation using second harmonic imaging and contrast administration improves the measurement of ventricular volumes. In the majority of existing echocardiographic equipment, however, harmonic imaging is not yet available. The aim of this study was to assess the feasibility of the measurement of left ventricular volumes and ejection fraction after intravenous administration of the contrast agent Levovist using standard echocardiographic equipment and fundamental imaging modality. In 10 patients with good-quality two-dimensional echo imaging, 4 g (400 mg/mL concentration) of Levovist was injected intravenously. Hewlett-Packard Sonos 2000 ultrasound equipment without second harmonic imaging capability was used. To avoid the destruction of microbubbles, the echo machine was set to produce only one end-systolic and one end-diastolic frame in each cardiac cycle (dual triggering). Native and contrast imaging measurements of left ventricular volumes and ejection fractions calculated by modified Simpson's rule were compared in the fundamental mode. Intraobserver and interobserver variability values were assessed. End-diastolic volumes in native continuous and triggered mode and by contrast echo were 126 +/- 48, 121 +/- 46, and 130 +/- 50 mL, respectively (NS), whereas end-systolic volumes were 79 +/- 48, 76 +/- 45, and 79 +/- 46 mL, respectively (NS). Calculated ejection fraction using the three different imaging modalities were 0.41 +/- 0.16, 0.41 +/- 0.16, and 0.42 +/- 0.16 (NS). The intraobserver and interobserver reproducibility values were excellent in triggered mode. Standard echocardiographic equipment with fundamental imaging modality in the triggered mode is suitable for the measurement of left ventricular volumes after intravenous Levovist administration. In clinically difficult patients, contrast echocardiography in triggered mode may be applied even if echocardiographic equipment does not have harmonic imaging possibility.

[Ventricular septal defect in osteogenesis imperfecta]. / Osteogenesis imperfecta membranosus kamrai septumdefektussal.

A 20-year-old man with osteogenesis imperfecta type one and membranous ventricular septal defect is presented. The association of these two connective tissue abnormalities is rare. It is the first reported case in Hungary.

[Short- and long-term changes in left ventricular function after surgical correction of mitral regurgitation]. / A balkamra-funkció rövid és hosszú távú változása mitralis regurgitatio sebészi megoldása után.

After surgical treatment of mitral regurgitation (MR) left ventricular dysfunction (LVD) can appear, which is an important predictive factor of long-term morbidity and mortality. The aim of our retrospective study was the assessment of left ventricular function (LVF) with M-mode echo measurement in the early and late postoperative period. Between 01. 01. 1992. and 31. 12. 1996. 70 patients with MR (29 men, 41 women, mean age 53.8 years) had at least three M-mode echoes: before surgery (I.), after surgery within 1 year (II.) and after the first postoperative year (mean 2.4 years) (III.). The patients were divided into subgroups: a) prosthetic valve replacement (MB) 58 patients, valvuloplasty (PL) 12 patients, b) coronary bypass grafting (C) 12 patients, no coronary disease (NC) 58 patients, c) chordal rupture (R) 24 patients, other etiology (NR) 46 patients. The evaluation of LVF was based on the ejection fraction (EF) calculated from the end-diastolic (Dd) and end-systolic (Ds) diameters on M-mode echo. Statistical analysis was made by paired and unpaired t test and with correlation analysis. The Dd decreased in the whole group (T) and in all subgroups in the II. and III. measurements compared to the I. (T: 58.9 vs. 52.6 vs. 53.2 mm; p < 0.0001, p < 0.0001). The Ds did not change in any group. In all groups except C the EF decreased at the II. measurement compared to the I. values (T: 57.7 vs. 47.8%, p < 0.0001; MB: 56.6 vs. 46.6%, p < 0.0001; PL: 62.8 vs. 53.8%, p = 0.05; NC: 59.6 vs. 48.3%, p < 0.0001; R: 61.5 vs. 50.4%, p < 0.0003; NR: 55.6 vs. 46.5% p = 0.0002), and it remained significantly lower in the III. measurement as well. At the III. measurement the EF was below 55% in all groups. In the groups T, MB, NC, NR the EF increased at the III. measurement compared to the II. (W: 47.8 vs. 51.3%, p = 0.002; PVR: 46.6 vs. 51.4%, p = 0.001; NC: 48.3 vs. 52.8%, p = 0.005; NR: 46.5 vs. 49.9%, p = 0.05). In the group C the I., II., III. EF values were not significantly different. There were 33 patients with preoperative EF more than 60%. In this group the EF decreased at the II. measurement, but the III. measurement showed normalization of the EF (67.03 vs. 52.58 vs. 59.27%, p < 0.0001, p < 0.01). There was no strong correlation between the preoperative EF, Ds and early or late postoperative EF (r = 0.54, r = -0.58; r = 0.62, r = -0.56). In patients operated for MR the postoperative EF is diminished independently on the preoperative EF, the operative technique or etiology. Left ventricular dysfunction concealed by the volume overload is unmasked by the decreased EF in the early postoperative period. LVD is partly reversible in the majority of the cases, however complete reversibility takes place only in cases with preoperative EF over 60%. Hence the operation of MR in patients with EF less than 60% is considered to be too late for the reversibility of LVD.

Effect of nitric oxide synthase inhibition on renal circulation and excretory function in anaesthetized rats.

The effects of nitric oxide synthase (NOS) inhibition (effected using L-NAME, 14 mg (kg body mass (BM))(-1), administered intravenously) on systemic and renal circulation and renal excretory function has been investigated in anaesthetized Wistar rats subjected to one of two different degrees of isotonic extracellular (EC) volume expansion (40 and 60 ml x kg(-1) (240 min)(-1)). The administration of L-NAME resulted in an increase in mean arterial blood pressure and total peripheral vascular resistance (TPR), and a significant reduction in cardiac output (CO) and the kidney fraction of CO in both experimental groups. The total renal blood flow (RBF) dropped from 557 + 43.4 to 149 +/- 13.1 ml x min(-1) (100 g BM)(-1) and from 592 +/- 45.9 to 191 +/- 16.3 ml x min(-1) (100 g BM)(-1) in the 40 and 60 ml x kg(-1) (240 min)(-1) experimental volume expansion groups, respectively. A redistribution of the intrarenal circulation from the medulla of the kidney toward the cortex may have occurred. The NOS inhibition induced a significant decrease in the glomerular filtration rate (GFR; from 1.18 +/- 0.10 to 0.53 +/- 0.08 ml x min(-1) (100 g BM)(-1) and from 1.26 +/- 0.07 to 0.73 +/- 0.08 ml x min(-1) (100 g BM)(-1) in the 40 and 60 ml x kg(-1) (240 min)(-1) experimental volume expansion groups, respectively), and the filtration fraction increased. The urine excretion dropped in parallel with the GFR, while the reduction in sodium and potassium excretion was more marked than that of the GFR, raising the possibility of a direct effect on the kidney tubules. The difference in EC volume expansion (the calculated increases in the EC volume in the last 90 min were 1.30 and 5.44% in the two time control groups and 3.66 and 7.45% in the two L-NAME-treated groups) did not induce any significant modification of the L-NAME effect.

Single cell and population activities in cortical-like systems.

Dynamics of single cells and large cell populations are the subject of investigation by using differently detailed models. Multicompartmental modeling techniques are used to systematically investigate the location-dependent effects of GABA-ergic inhibition on the firing patterns of hippocampal pyramidal cells. Appearance of stochastic resonance in a model of mitral and granule cells of the olfactory bulb is demonstrated by using a single-compartmental model approach. Spatial propagation of synchronized activities in hippocampal slices are studied by a model of large neural populations.

Thrombolysis is superior to heparin for non-obstructive mitral mechanical valve thrombosis.

BACKGROUND AND AIM OF THE STUDY: Non-obstructive prosthetic valve thrombosis (PVT) is a unique subset that features clinical presentation without heart failure, and may be asymptomatic. Thrombolysis has been accepted for obstructive PVT, but treatment strategies of non-obstructive PVT are controversial. This study compared the efficacy and safety of thrombolysis and heparin treatment in these patients. METHODS: Between 1993 and 1998, 20 consecutive patients were found by multiplane transesophageal echocardiography (TEE) to have non-obstructive PVT. TEE was performed for peripheral embolism in two patients, stroke or transient ischemic attack in six, stroke and fever in two, fever in one patient, as a routine postoperative examination in two patients, and for other reasons in seven. Patients were allocated to two groups: group I (n = 8) received streptokinase-mediated fibrinolysis; group II (n = 12) received intravenous heparin by infusion. Treatment was monitored using TEE. RESULTS: There was no difference between patient groups with regard to sex, age, type of prosthesis and time since operation, though anticoagulant status was more often inadequate in group II. By TEE, valve motion was normal in all patients. In group I, all thrombi were mobile and 5-13 mm in diameter; in group II, all thrombi but three were mobile and 3-18 mm in diameter. In group I, thrombolysis was successful in all patients, without complications, within 6-72 h. In group II, heparin treatment was successful in six patients in 3-32 days. In one patient, seven days' of unsuccessful heparin was followed by two months' successful coumarin therapy. Among five unsuccessful cases, the thrombus size increased in four (three became obstructive in 7-35 days); all four patients were switched to fibrinolysis, which was successful without complications in 12-60 h. The fifth patient developed a stroke after nine days of heparin treatment and was subsequently operated on. CONCLUSIONS: Non-obstructive PVT may be asymptomatic in one-third of patients. Thrombolysis is an efficient and safe treatment, and may be first-line therapy if there is no contraindication. Heparin treatment was successful in about one-half of our cases in the presence of sessile or small thrombi and inadequate anticoagulant status. In unsuccessful cases, thrombi became obstructive or caused stroke during heparin therapy, the adequate duration of which remains unclear.

[Intravenous adenosine infusion in the assessment of coronary flow reserve in hypertension. Transesophageal Doppler echocardiographic study]. / Intravénás adenozin a coronaria áramlási rezerv kimutatására hypertoniában. Transoesophagealis Doppler-echokardiográfiás vizsgálat.

UNLABELLED: In hypertensive patients with normal coronary angiography typical chest pain may be caused by microvascular coronary artery disease. This can be confirmed by decreased coronary flow reserve (CFR). Adenosine test with transesophageal echocardiography was chosen for the measurement of CFR. There are only few reports in the literature which utilized this test. The purpose of this study was primarily to further elucidate some technical aspects and to evaluate CFR in hypertensive patients with angina, positive stress test and normal coronary angiography. Out of 12 such consecutive patients the adenosine test was successful in 11. Adenosine was given in 140 mcg/kg/min dose as a 5 minute continuous infusion. Mean coronary flow velocity (Vm), CFR, baseline coronary flow resistance (CVR) and maximal coronary dilation (CRR) in the left anterior descending artery were measured and calculated by multiplane transesophageal Doppler echocardiography. There was a 43% increase of heart rate and a 7% decrease of systolic blood pressure. Baseline Vm was 36 +/- 16 cm/s, CFR 2.4 +/- 0.4, baseline CVR was 2.8 +/- 1.0 mmHg/s/an, CRR was 2.4 +/- 0.4. Left main coronary dimension did not change. There was no important side effect. While baseline Vm was similar to normal values in the literature, CFR and CRR were decreased compared to normals. There was no correlation between baseline Vm or heart rate and CFR but a direct correlation was found between baseline CVR and CRR (r = 0.54). Peak effect of adenosine was achieved at 3-5 minutes. CONCLUSIONS: Adenosine-TEE infusion test is a safe and easy to perform technique to assess CFR in hypertensive patients. In hypertensive patients with documented ischemia and normal coronary angiography the coronary flow reserve is decreased.

[Viable myocardium revealed by contrast echocardiography]. / Eletképes myocardium kimutatása kontraszt-echokardiográfia segítségével.

In patients with acute ischemic syndrome left ventricular dysfunction may indicate necrotic myocardium as well as viable tissue. Among the well known non-invasive techniques like dobutamine echocardiography, rest-redistribution thallium scintigraphy or positron emission tomography a new method, contrast echocardiography is evolving. In the presented case stunning resulting in left ventricular aneurysm formation was confirmed after intravenous injection of contrast agent and the use of intermittent harmonic imaging in the acute phase of ischemia. The negative coronary angiography and the complete restoration of the left ventricular function confirmed the results of contrast echocardiography. With the development of new second generation contrast agents and new techniques contrast echocardiography will become a feasible method for detection of viable myocardium after intravenous injection.

Contrast echocardiography in the diagnosis of myocardial stunning.

The identification of viable myocardium within dysfunctional myocardium has important clinical implications. By using a microvascular tracer, myocardial contrast echocardiography may have the potential for prediction of myocardial viability in the acute and subacute phases of myocardial infarction. In the case presented, the normal myocardial perfusion observed after intravenous injection of the contrast agent, combined with severe wall motion abnormality following prolonged chest pain, suggested myocardial stunning. This was confirmed by normal coronary angiography and by restoration of normal left ventricular function at 1-month follow-up echocardiography.

An adult case of Kawasaki disease with multiplex coronary aneurysms and myocardial infarction: the role of transesophageal echocardiography.

Kawasaki disease (mucocutaneous lymph node syndrome) is an acute inflammatory disease that primarily affects infants and young children. In spite of proper therapy, coronary aneurysms develop in 10 to 25% of cases. Adult diagnosis of coronary aneurysm, presumably caused by Kawasaki disease, is rare. A 37-year-old male patient with previous inferior wall myocardial infarction (MI) was admitted with an acute anterior wall MI. Coronary angiography, performed 2 weeks after successful thrombolytic therapy, showed right coronary artery occlusion and multiplex (left main, left anterior descending, left circumflex, right coronary artery) giant coronary aneurysms. Transthoracic echocardiography was unable to detect the aneurysms. Transesophageal echocardiography (TEE) visualized a large left main coronary aneurysm with an occlusive thrombus and measured low flow velocity (0.2 m/s) in the proximal left anterior descending artery. At 4 weeks control, TEE showed marked regression of the thrombus, and it was not detectable after 6 months of oral anticoagulation with acenocumarol (International Normalized Ratio: 3-3.5) and standard postinfarction therapy. After 2 years of follow-up, the patient has no symptoms, and myocardial ischemia could not be provoked by stress tests [treadmill, dipyridamole single-photon emission computed tomography (SPECT)]. We conclude that, for diagnosis and follow-up of adult Kawasaki disease, transesophageal echocardiography is indicated. The importance and efficacy of long-term anticoagulant treatment should be emphasized in this disease.

[Effect of chronic amiodarone therapy on left ventricular function in dilated cardiomyopathy studied by the new Doppler-index]. / Krónikus amiodaron kezelés bal kamra-funkcióra kifejtett hatásának vizsgálata az új Doppler-index alkalmazásával dilatatív cardiomyopathiában.

UNLABELLED: Several noninvasive techniques have been used for the assessment of systolic and diastolic function. In most forms of cardiac disease however systolic and diastolic dysfunction coexist, hence a combined measure of left ventricular performance may be more reflective than their assessment alone. A recently recommended new Doppler index is supposed to be useful for this purpose. This index is the ratio of the sum of both isovolumic times and the ejection time. The objective of this study was to assess the features of the new index and then to prospectively evaluate the effect of chronic amiodarone treatment on left ventricular function using the new index and standard methods in dilated cardiomyopathy. RESULTS: Normal values of the new index are within a narrow range, it separates the normal and the dilated cardiomyopathy patients without overlap, it is not heart rate dependent in either group and it is not affected by either mitral regurgitation or left bundle brunch block. The index is inversely related to the relative diastolic filling time in both groups. In severe dilated cardiomyopathy after one year amiodarone treatment there was a significant decrease of heart rate, the new Doppler index and a significant increase of ejection fraction, ejection time and relative diastolic filling time. These changes were significant already at 1 month except the new index. These results suggest that the beneficial effect of amiodarone is due to the increase of diastolic filling time rather than to a positive inotropic effect. CONCLUSIONS: 1. The new Doppler index is simple and can be easily utilized in the differentiation of normal and abnormal left ventricular function: 2 chronic amiodarone treatment may be indicated even in the absence of arrhythmia to improve left ventricular function in severe heart failure.

Guidelines for management of left-sided prosthetic valve thrombosis: a role for thrombolytic therapy. Consensus Conference on Prosthetic Valve Thrombosis.

OBJECTIVES: We sought to form a consensus recommendation for management of prosthetic valve thrombosis (PVT) from previous case and uncontrolled reports from a consensus of international specialists. BACKGROUND: PVT and thromboembolism relate to inadequate anticoagulation and valve type and location. PVT is suspected by history (dyspnea) and auscultation (muffled valve sounds or new murmurs) and confirmed by Doppler echocardiography showing a marked valve gradient. METHODS: A consensus conference was held to recommend management of left-sided PVT. RESULTS: Transesophageal Doppler echocardiography is used to visualize abnormal leaflet motion and the size, location and mobility of thrombus. Thrombolysis is used for high risk surgical candidates with left-sided PVT (New York Heart Association functional class III or IV) because cerebral thromboembolism may occur in 12% of patients. Duration of thrombolysis depends on resolution of pressure gradients and valve areas to near normal by Doppler echocardiography performed every few hours. Lysis is stopped after 72 or 24 h if there is no hemodynamic improvement (operation indicated). Heparin infusion with frequent measurement of activated partial thromboplastin time (aPTT) begins when aPTT is more than twice control levels and can be converted to warfarin (international normalized ratio [INR] 2.5 to 3.5) plus aspirin (81 to 100 mg/day). Patients in functional class I or II have lower surgical mortality, and those with large immobile thrombi on the prosthetic valve or left atrium have responded to endogenous lysis with combined subcutaneous heparin every 12 h (aPTT 55 to 80 s) plus warfarin (INR 2.5 to 3.5) for 1 to 6 months. Operation is advised for nonresponders or patients with mobile thrombi. CONCLUSIONS: Thrombolysis, followed by heparin, warfarin and aspirin, is advised for high risk surgical candidates with left-sided PVT.