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Thomas Bartel

Publications and source records attributed to Thomas Bartel.

36 records · Page 2Linked to original sources

Tissue Doppler analysis is hindered in abnormal wall motion and changes in afterload.

BACKGROUND: Tissue Doppler (TD) analysis is used to estimate contractility. However, interference with hemodynamics has not been investigated. OBJECTIVE: To evaluate the effect of hemodynamic conditions and wall motion abnormalities on TD indices. METHODS: TD indices were obtained in 16 dogs and correlated with hemodynamics and wall thickening. RESULTS: An inverse relation between TD indices and systemic vascular resistance was observed when afterload-related parameters were included in the analysis (early systolic subendocardial velocity: r((multiple regression))=0.82, P<0.0001 vs. r((simple regression))=0.57, P=0.0002). Early systolic TD data were more closely related to hemodynamics than those derived from the entire systole. TD data did not correspond to the hyperkinesia of the contralateral wall in myocardial infarction, whereas the increase of gradient parameters reflected hypercontractility (P<0.05). CONCLUSION: TD indices are directly related to contractility and inversely to afterload. They do not reflect wall motion of those segments not involved in regional ischemia.

Animals↗

Partial cut-off of the left ventricle: determinants and effects on volume parameters assessed by real-time 3-D echocardiography.

A total of 44 patients with coronary artery disease underwent real-time three-dimensional (3-D) echocardiography for end systolic (ES) and end diastolic (ED) left ventricular (LV) volumetric analysis to assess the effect of partial cut-off of the left ventricular (LV) apex on volumetric analysis by apical transthoracic echocardiography. Patients with LV cut-off were assigned to either group 1 (ejection fraction, (EF) < 49%) or group 2 (EF > or = 49%). Patients were additionally classified as group A if they had anterior or apical wall motion abnormalities (WMA) or group B if they had only inferoposterior or lateral WMA. Partial LV cut-offs were found in 22 subjects (50%). The estimated end diastolic cut-off volumes were as follows: 8.6 +/- 3.2 mL (group 1), 4.3 +/- 2.4 mL (group 2), 9.1 +/- 3.3 mL (group A) and 1.4 +/- 0.8 mL (group B). In group 1, more patients with LV volume cut-off were found than in group 2: chi(2) = 4.52, p < 0.05; and in group A more than in group B: chi(2) = 8.08, p < 0.01. In all, partial LV cut-off led to underestimation of LV volumes: 5.9 +/- 4.7 ml (ED) vs. 2.1 +/- 1.3 ml (ES), p <0.02. In conclusion, LV cut-offs can potentially alter the accuracy of echocardiographic volumetric analysis, particularly in anterior or apical WMA.

Adult↗

Analysis of global systolic and diastolic left ventricular performance using volume-time curves by real-time three-dimensional echocardiography.

BACKGROUND: Left ventricular (LV) volume-time curves (VTC) have been described to provide quantitative data on the dynamics of global LV performance beyond ejection fraction. However, generation of VTCs by conventional 2-dimensional imaging techniques is inherently limited because of inaccurate geometric volume assumptions. We, therefore, studied whether the new concept of volumetric scanning as realized by real-time 3-dimensional echocardiography (RT-3DE) can be used to provide accurate VTCs. METHODS: In 30 healthy participants, VTCs were generated from 18 to 24 absolute LV volumes per second by transthoracic RT-3DE and compared with magnetic resonance imaging (MRI) used for reference. LVs were traced manually in 9 to 11 parallel, short-axis planes and volumes calculated by disk method. From VTCs, we determined peak ejection rate (PER), peak early filling rate (PFR), time to PER and PFR, and end-diastolic and end-systolic volumes. For initial clinical application, 2 patient groups of coronary (n = 15) and hypertensive heart disease (n = 16) were studied. RESULTS: In healthy participants, VTCs agreed with MRI (mean errors: PER, -39 +/- 67 mL/s; PFR, -18 +/- 84 mL/s; time to PER, 8 +/- 21 milliseconds; time to PFR 4 +/- 18 milliseconds [not significant vs 0]) whereas VTCs in coronary and hypertensive groups revealed significantly impaired diastolic function. Scanning time for VTCs was only 1 to 2 minutes by RT-3DE and 8 +/- 2 minutes by MRI (P <.001) and time for offline analysis was 22 +/- 5 minutes versus 24 +/- 4 minutes by MRI (not significant). CONCLUSIONS: Generation of VTCs by RT-3DE is feasible and shows excellent agreement with MRI used for reference. Thus, VTCs by RT-3DE is a promising new approach providing access to quantitative information on global LV performance such as LV filling rates that is currently unavailable for the cardiologist.

Adult↗

Noninvasive assessment of microvascular function in arterial hypertension by transthoracic Doppler harmonic echocardiography.

OBJECTIVES: The present study sought to investigate the use of transthoracic Doppler harmonic echocardiography (TTDHE) to evaluate changes in coronary flow dynamics due to microvascular dysfunction. BACKGROUND: Coronary flow velocity reserve (CFVR) measurements by TTDHE are useful for assessing epicardial coronary artery stenoses. It remains unclear, however, if microvascular disease can be detected. METHODS: In 54 patients with chest pain, intracoronary Doppler (ICD) and TTDHE were used to measure average peak velocity at baseline and hyperemia. Significant coronary lesions had been ruled out by both angiography and intravascular ultrasound. Comparative measurements were performed in the distal left anterior descending coronary artery after intracoronary and intravenous administration of adenosine, and CFVR was calculated. Hypertensive patients (n = 25) were studied and compared to a control group (26 normotensive individuals). RESULTS: Three patients (5%) had to be excluded because of insufficient image quality or side effects. In both groups, TTDHE-derived CFVR data correlated closely with ICD measurements (group 1: y = 0.67x + 0.076, standard error of estimate [SEE] = 0.25, r = 0.87, p < 0.001; group 2: y = 0.64x + 1.11, SEE = 0.26, r = 0.87, p < 0.001). CFVR was lower in hypertensives than in normotensive controls (2.44 +/- 0.49 vs. 3.33 +/- 0.40, p < 0.001, cut point = 2.84). CONCLUSIONS: The newly described echocardiographic method is suitable for assessing microvascular dysfunction noninvasively and corresponds well to invasive measurements.

Adult↗

Systematic use of a collagen-based vascular closure device immediately after cardiac catheterization procedures in 1,317 consecutive patients.

Despite recent advances in interventional cardiology, vascular access complications continue to be a significant problem. Conventional manual compression of the femoral access site is associated with prolonged immobilization and significant patient discomfort. We investigated the performance of a collagen-based closure device applied immediately after catheterization and its complication rate in 1,317 consecutive patients undergoing cardiac catheterization or coronary angioplasty. Patients undergoing coronary angioplasty (n = 644) received more heparin than patients with diagnostic cardiac catheterization (n = 673; 9,675 +/- 1,144 IU vs. 6,419 +/- 2,211 IU; P < 0.0001). Deployment success rates of the closure device were comparable for patients undergoing diagnostic vs. interventional procedures (95.8% vs. 96.7%; P = 0.46). Complete hemostasis immediately after deployment of the device was achieved in > 90% of all patients, but was lower in the interventional group (93.7% vs. 90.6%; P = 0.05). Major complications including any vascular surgery, major bleeding requiring transfusion, retroperitoneal hematoma, thrombosis or loss of distal pulses, groin infections, significant groin hematoma, and death were observed in 0.53% of all patients, with no differences between diagnostic or interventional patients (0.62% vs. 0.45%; P = 0.953). Subgroup analysis revealed female gender as a predictor of access site complications. Systematic sealing of femoral access sites after both diagnostic and interventional procedures allows for immediate sheath removal with reliable hemostasis. The use of a collagen-based closure device is associated with a low rate of clinically significant complications.

Aged↗

Non-invasive assessment of coronary flow velocity reserve: a new method using transthoracic Doppler echocardiography.

Transthoracic Doppler echocardiography (TTDE) allows noninvasive flow measurement in the distal left anterior descending artery (LAD). The feasibility of detecting coronary flow by contrast-enhanced TTDE with second harmonic technique was assessed, the coronary flow velocity reserve (CFVR) was evaluated in comparison to intracoronary Doppler flow (ICD) analysis and the CFVR after PTCA in LAD was investigated. In 77 (96%) of 80 patients, CFVR was successfully determined with intravenous adenosine infusion. Doppler signal quality was evaluated in the first 46 patients by use of intravenous Levovist infusion and second harmonic technique. The Doppler flow was not visible in 1. patient only. CFVR determined from TTDE (2.77 +/- 0.65) was correlated closely with those from ICD (2.88 +/- 0.78) measurements (y = 0.73x + 0.67, r = 0.87, P < 0.001). In conclusion, TTDE is a feasible method and provides reliable data on CFVR which can be used for follow-up after PTCA.

Adenosine↗

[Echocardiography diagnosis of diastolic heart failure].

BACKGROUND: Left ventricular diastolic dysfunction can be diagnosed if clinical signs of heart failure and normal ejection fraction are found. Beside clinical signs of heart failure and criteria from catheterization studies like abnormal left ventricular relaxation, filling and/or compliance echocardiography provides valuable parameters for the assessment of diastolic dysfunction. ECHOCARDIOGRAPHIC DEGREES OF SEVERITY: By the use of various parameters diastolic dysfunction can be differentiated into four degrees of severity, which are of great prognostic importance. If more than one echocardiographic parameter is used, sensitivity for the assessment of diastolic dysfunction becomes nearly 100%. Conventional parameters include isovolumetric relaxation time (IVRT) measured by pulsed Doppler, the ratio of rapid filling and atrial filling velocity (E/A), deceleration time of rapid mitral inflow as well as the ratio of systolic and diastolic pulmonary venous flow velocities. In patients with signs of diastolic heart failure and a normal E/A ratio pulmonary venous flow pattern can help to unmask "pseudonormalization" as the transition from abnormal relaxation to restriction. These parameters, however, are preload-dependent and do not provide intrinsic left ventricular properties. Even in atrial fibrillation, left ventricular filling pressure can be assessed. NEW METHODS: Two novel approaches, color Doppler M-mode of left ventricular inflow and tissue Doppler of the mitral annulus, are relatively preload-independent and allow direct estimation of relaxation and filling pressure. By the means of real-time 3-D echocardiography we developed a new method for the non-invasive assessment of rapid filling rate (PFR), thereby completing the echocardiographic approaches to determine diastolic dysfunction. CONCLUSION: The broad spectrum of approaches available today makes echocardiography the first choice for the assessment of diastolic dysfunction.

Echocardiography↗

[3-D echocardiography: new developments and future prospects].

Due to limitations in transthoracic and occasionally transesophageal 2-D echocardiography with respect to volumetric analysis and morphologic and functional assessment in patients with congenital malformations and valvular heart disease, additional diagnostic tools have been established. In parallel with the rapid evolution in computer technology, 3-D echocardiography has grown into a well-developed technique, such as volume-rendered 3-D reconstruction, capable of displaying dynamic morphology depicting depth of the structures, their attachment, and spatial relation to the surrounding tissue. Nevertheless, the complexity of data acquisition and data processing required for adequate dynamic 3-D echocardiographic imaging and volumetric analysis does not allow to use this approach routinely. The commonly used dynamic 3-D echocardiography means off-line computer-assisted image reconstruction from a series of cross-sectional echocardiographic images using currently available transesophageal and transthoracic transducers. Alternatively, real-time 3-D echocardiography based on novel matrix, phased-array transducer technology has been introduced. Although this technique can be easily combined with any routine examination, its clinical use is limited because of a lower image quality in comparison with dynamic 3-D echocardiography. Up to now, there is no transesophageal approach available using real-time 3-D echocardiography. Recently, dynamic 3-D echocardiographic technique has matured noticeably. Beside the well-known sequential scanning, which is characterized by a fixed probe and patient in space and predetermined motion of the transducer, the freehand scanning using an electromagnetic location system has found its way to clinical environment. The main advantage of this technique is that the transducer can be freely moved by the examiner and, thus, the data set acquired within a routine examination. Also 3-D rendering and display have been developed further. In this respect, especially the "real-time rendering mode" allowing the reconstructed 3-D image to be animated and moved in space and to look at it from different perspectives has gained increasing acceptance. In valvular heart disease, reconstructive surgical treatment is aspired. 3-D echocardiographic imaging is the only technique providing "surgical views" prior to opening the heart. It is capable of distinguishing particular destructive substructures of the valves and the valvular apparatus. Especially in mitral valvular reconstruction, it is of clinical importance to achieve optimal surgical results. With respect to volumetric and mass analysis, 3-D echocardiography is more accurate and reproducible in comparison with conventional 2-D analysis. It provides data independent of geometric assumptions, what may considerably influence the results in the presence of wall motion abnormalities, especially in aneurysmatic ventricles. Volumetric analysis of the aneurysmal portion may also be helpful prior to surgical resection. 3-D echocardiography can also be recommended as a valuable additional approach to atrial septal defect (ASD), corrected transposition of the great arteries, cor triatriatum, and, within limits, to ventricular septal defect (VSD) as well. Especially with respect to ASD and VSD, the potential significance of 3-D echocardiography prior to device closure is emphasized. At present, its additional information in decision-making and the increasing number of clinical cases that can be addressed and answered already justify the clinical use of this technique.

Echocardiography, Three-Dimensional↗

Real-time three-dimensional echocardiography for improved evaluation of diastolic function using volume-time curves.

BACKGROUND: Accurate assessment of left ventricular function is of the greatest importance in clinical cardiology for decision making. Diastolic dysfunction is getting more concern as a cause of heart failure while, currently used non-invasive modalities for diagnosing diastolic abnormalities have significant limitations. Dynamic left ventricular volume change was applied for the evaluation of diastolic function by various techniques that have been demonstrated to be of diagnostic value. However, it has not been accepted into clinical practice because existing techniques are either invasive, inaccurate, expensive or time consuming. REAL-TIME THREE-DIMENSIONAL ECHOCARDIOGRAPHY: Real-time three-dimensional (3-D) echocardiography is a new ultrasound technique that provides transthoracic volumetric images of the heart in real time. Thereby, the acquired images are ideally suited for the assessment of dynamic left ventricular volume change. Generation and analysis of left ventricular volume-time curves by real-time 3-D echocardiography has been demonstrated to be feasible in normal subjects and patients and accuracy of volume-time curves was good compared to magnetic resonance imaging. We compare the new real-time 3-D echo approach with the advantages and limitations of existing noninvasive and invasive techniques.

Cardiac Volume↗

Biomechanical modeling of hemodynamic factors determining bulging of ventricular aneurysms.

BACKGROUND: Ventricular aneurysm formation is a frequent complication of transmural myocardial infarction. The hemodynamic determinants of aneurysmal bulging remain unclear. METHODS: A rubber heart placed in a water tank served as an in vitro model. Rhythmic injections of specific volumes into the tank simulated heart beats. The heart rate was adjustable in increments. A section of the heart model's wall was shielded from compression to simulate an aneurysm. To quantitate the relation between hemodynamics and bulging, pressures, echocardiographic measurements of maximal expansion, and mean velocity were recorded. Bulging volume, stroke volume, aneurysmal wall stress, and systemic resistance were calculated. RESULTS: The mean velocity was the echocardiographic factor most closely related to bulging volume (r = 0.92, p < 0.01). When bulging indices were compared with hemodynamics, bulging volume and mean velocity were found to directly depend on heart rate (r = 0.66, p < 0.01; r = 0.70, p < 0.01). Polynomial regression revealed bulging volume to reach minimal values near 80 beats/min. Maximal systolic aneurysmal wall stress was closely related to the peak positive rate of pressure change (r = 0.94, p < 0.01) and moderately to stroke volume (r = 0.75, p < 0.01). Filling pressures were unrelated to bulging. The greatest bulging volume reduction occurred below 790 dynes x s x cm(-5); bulging was practically eliminated at systemic resistance values less than 395 dynes x s x cm(-5). CONCLUSIONS: Aneurysmal bulging and aneurysm formation depend mainly on heart rate, contractility, and afterload. This suggests that hemodynamic management may affect the extent of bulging in a clinical setting.

Biomechanical Phenomena↗

Intracardiac and intraluminal echocardiography: indications and standard approaches.

In particular clinical scenarios, transthoracic and transoesophageal echocardiography (TEE) have limitations. This study sought to test if intracardiac and intraluminal echocardiography (ICLE), including 2-D, M-mode and Doppler analysis with a miniaturised, multiple-frequency transducer-tipped catheter, is suitable for assessing distinct cardiac and vascular disorders. ICLE was employed in 10 animals using 6 standard approaches. In 12 patients undergoing device closure of patent foramina ovalia (PFO) (n = 6) or atrial septal defects (ASD) (n = 3), or aortic stent implantation (n = 3), interventional procedures were guided by ICLE and, for comparison, also by TEE. ICLE provided enhanced diagnostic information on the aorta, cardiac valves, main pulmonary vessels and both atria and, therefore, added to the diagnostic spectrum of TEE. Especially for guiding interventional procedures (e.g., device closure of atrial septal defects and patent foramina ovalia), ICLE was shown to be helpful. Compared with the conventional approach, the technique reduced fluoroscopy time for device closure procedures: 6.5 min vs. 8.9 min, p < 0.0011. With the patient in a supine position, ICLE was better tolerated than TEE. Complications did not occur, either with ICLE or with TEE. In conclusion, ICLE adds to conventional echocardiography and promises to become a clinical alternative for guiding interventional procedures.

Adult↗

Tei-index in symptomatic patients with primary and secondary mitral regurgitation.

Significant mitral regurgitation (MR) may result from primary valve dysfunction or develop secondary to ischemic or dilated cardiomyopathy. The index 'isovolumic contraction time and isovolumic relaxation time divided by ejection time' (ICT + IRT/ET, 'Tei-index') is a well established measure of global cardiac function in patients with dilated cardiomyopathy and cardiac amyloidosis. We sought to define the diagnostic value of the Tei-index in patients with significant MR of various origin. Sixteen asymptomatic control subjects (8 male (m)/8 female (f), age 62+/-8 years, control group), 12 patients with primary MR (PMR) (mean grade 3.1+/-0.3, due to rupture of the chordae tendineae (n = 2), flail leaflet (n = 1), valve prolapse (n = 6) or rheumatic degeneration (n = 3), 6 m/6 f, age 58+/-18 years, NYHA class 2.5+/-0.3, PMR group) and 25 patients with secondary MR (SMR) (mean grade 3.1+/-0.3; due to ischemic (n = 14) or dilated cardiomyopathy (n = 10), 19 m/6 f, age 60+/-11 years, NYHA class 3.1+/-0.5, SMR group) underwent conventional two-dimensional (2D) and Doppler echocardiographic examination including measurement of the Tei-index. In the SMR group, left ventricular ejection fraction was reduced compared to the control and the PMR group (29+/-13% vs. 59+/-8% and 59+/-8%, p < 0.001 for both comparisons). The E/A ratio was elevated in PMR and SMR groups in comparison to the control group (1.74+/-0.44 and 1.70+/-0.45 vs. 1.09+/-0.28, p < 0.05). The Tei-index was easily and reproducibly measured in all study subjects. The mean value of the index was significantly elevated in the SMR group compared to control and PMR groups (0.87+/-0.3 vs. 0.42+/-0.07 and 0.38+/-0.05, p < 0.001). The difference between the control group and the PMR group did not reach statistical significance. In MR patients, receiver operating characteristic curve analysis for the Tei-index yielded an area under the curve of 0.96+/-0.03 for separating the PMR and the SMR group. Using a Tei-index > 0.51 as a cutpoint, SMR was identified with a sensitivity of 92% and a specificity of 88%. In MR patients, a significant correlation between left ventricular end-systolic volume and the Tei-index was observed (r = 0.71, p < 0.01). The Tei-index is a feasible and sensitive indicator of overall cardiac dysfunction in severely symptomatic patients with significant MR secondary to ischemic or dilated cardiomyopathy. The index is in the normal range in symptomatic patients with PMR and preserved systolic function. The Tei-index differentiates between patients with SMR and PMR and may be useful in the work-up of such patients.

Echocardiography, Doppler↗

Impact of disease activity on left ventricular performance in patients with acromegaly.

BACKGROUND: In patients with acromegaly, abnormalities of systolic and diastolic left ventricular (LV) performance, mostly associated with hypertension or LV hypertrophy, have been reported. We used 2-dimensional/Doppler echocardiographic methods and tissue Doppler imaging (TDI) to elucidate the impact of disease activity on LV function in patients with acromegaly. METHODS: In a prospective study design, 15 patients with active acromegaly (AA group; mean age-adjusted serum insuline-like growth factor-I [IGF-I] level, 420 +/- 170 ng/mL, mean growth hormone nadir during 75-g oral glucose load, 12.3 +/- 30.1 microg/L), 18 patients with cured (n = 14, mean IGF-I level 205 +/- 115 ng/mL, mean growth hormone nadir during glucose load 0.72 +/- 0.34 microg/L) or well-controlled (n = 4, normal age-adjusted ranges of IGF-I levels with medication with somatostatin analogues 354 +/- 88 ng/mL) acromegaly (CA group), and 24 control subjects (control group) underwent 2-dimensional/Doppler echocardiographic measurements, including assessment of the Tei index (isovolumic contraction time and isovolumic relaxation time divided by ejection time). Systolic and diastolic mitral annular velocities (peak systolic velocity, peak early diastolic velocity [E'], peak late diastolic velocity [A'], E'/A' ratio) were derived from pulsed TDI. RESULTS: No significant differences between study groups were observed with respect to muscle mass and systolic parameters, such as ejection fraction, fractional shortening, and peak systolic velocity. In patients with AA, E' and the E'/A' ratio were lower than in control and CA subjects (AA 6.8 +/- 1.7 cm/s, control 10.0 +/- 1.7 cm/s, CA 9.1+/- 3.0 cm/s, P <.01 AA vs control, P <.05 AA versus CA, AA 0.68 +/- 0.22, control 0.98 +/- 0.16, CA 0.89 +/- 0.37, P <.01 AA vs control and CA, respectively). In comparison with control subjects and patients with CA, patients with AA had a reduced mitral peak velocity of early/late filling ratio (AA 0.78 +/- 0.22 m/s, control 1.12 +/- 0.33 m/s, CA 1.11 +/- 0.36 m/s, P <.05 AA vs control and CA) and a prolonged deceleration time (AA 223 +/- 41 ms, control 188 +/- 26 ms, CA 185 +/- 25 ms, P <.05 AA vs control and CA). The Tei index was significantly elevated in patients with AA in comparison with control subjects and patients with CA (AA 0.54 +/- 0.13, control 0.40 +/- 0.09, CA 0.44 +/- 0.10, P <.05 AA vs control and CA). No significant differences were observed between control subjects and patients with CA with respect to mitral flow-derived variables, TDI parameters, and the Tei index. CONCLUSION: Disease activity has a significant impact on LV performance in patients with acromegaly. In subjects with active disease, diastolic dysfunction and beginning impairment of overall LV performance are present. In patients with cured/well-controlled disease, systolic and diastolic function appear normal.

Acromegaly↗

Severe aortic valve stenosis with preserved and reduced systolic left ventricular function: diagnostic usefulness of the Tei index.

BACKGROUND: In patients with severe aortic valve stenosis (AS), the onset of heart failure is associated with increased mortality and higher operative risk. Heart failure may result from either systolic, diastolic, or "overall" left ventricular dysfunction. The index "isovolumic contraction time and isovolumic relaxation time divided by ejection time" was shown to be a sensitive indicator of "overall" cardiac dysfunction in patients with dilated cardiomyopathy and cardiac amyloidosis. We sought to define the role of the Tei index in patients with severe AS and to validate this index against conventional measures of systolic and diastolic LV function. PATIENTS AND METHODS: Fifty-three participants underwent left heart catheterization for invasive measurement of LV end-diastolic pressure as a marker of diastolic function: 10 AS patients (valve orifice 0.6 +/- 0.2 qcm) with depressed systolic LV function (defined by LV ejection fraction < or = 45% [mean 32% +/- 8%], 7 male/3 female, 72 +/- 10 years old, DAS group), 22 AS patients (valve orifice 0.7 +/- 0.2 qcm) with preserved systolic LV function (ejection fraction > 45% [mean 55% +/- 6%], 13 male/9 female, 71 +/- 11 years old, PAS group) and 21 asymptomatic control participants (ejection fraction > 45% [mean 62% +/- 8%], 14 male/7 female, 66 +/- 8 years old, CON group). Within 24 hours from catheterization, conventional 2-dimensional and Doppler echocardiographic examination including measurement of the Tei index was performed. RESULTS: LV end-diastolic pressure was elevated in the DAS and in the PAS group in comparison with control participants (32 +/- 6 mm Hg and 22 +/- 7 mm Hg vs 11 +/- 4 mm Hg, respectively, P <.01 for both comparisons). DAS patients were in a higher New York Heart Association functional class than PAS patients (3.2 +/- 0.4 vs 2.2 +/- 0.4, P <.001) The Tei index was easily and reproducibly obtained in all study participants. In the DAS group, isovolumic contraction time was prolonged and ejection time was shortened in comparison with the CON group (102 +/- 20 ms vs 52 +/- 15 ms, P <.01; and 235 +/- 44 ms vs 316 +/- 45 ms, P <.01), resulting in a significantly increased Tei index (0.78 +/- 0.28 vs 0.40 +/- 0.11, P <.01). In the PAS group, isovolumic relaxation time was shortened (62 +/- 18 ms vs 81 +/- 26 ms for the CON group, P <.01) and ejection time was prolonged (335 +/- 34 ms vs 316 +/- 45 ms for the CON group, P <.05), resulting in a decreased Tei index (0.29 +/- 0.12 vs 0.40 +/- 0.11, P <.05). Receiver operating characteristic curve analysis for the Tei index yielded an area under the curve of 0.98 +/- 0.03 for separating DAS and PAS patients. Using a Tei index greater than 0.42 as a cutoff, DAS patients were identified with a sensitivity of 100% and a specificity of 91%. CONCLUSION: The Tei index is significantly increased in patients with severe AS and depressed overall cardiac LV function. In AS patients with predominant diastolic dysfunction, in whom systolic function is preserved, the index is decreased in comparison with control patients. The index differentiates between symptomatic AS patients with depressed and less symptomatic AS patients with preserved systolic LV function, and may thus provide relevant information in the work-up and care of such patients.

Aged↗

Central-nervous side effects of midazolam during transesophageal echocardiography.

BACKGROUND: Midazolam is a broadly used drug that can enhance tolerance to transesophageal echocardiography (TEE) in patients with cardiac conditions. Adverse reactions to midazolam have been described previously. We describe central-nervous side effects in 6 of 104 consecutive patients. METHODS: One hundred four patients undergoing TEE-diagnostic procedure were investigated. TEE was performed using a SSA 360 Power Vision ultrasound unit (Toshiba, Tokyo, Japan) and a 5- to 6-MHz probe. Indication for TEE was evaluation of cardiac valves (6), search for cardiac embolism (23), patent foramen ovale or atrial septum defect (20), left ventricular dysfunction (11), aortic dissection (7), and other (37). Midazolam and, if necessary, the benzodiazepine antagonist flumazenil (0.25-0.5 mg) were administered intravenously. RESULTS: The mean cumulative dose of midazolam administered in small fractions was 4.8 +/- 2 mg. In 6 of 104 patients (5.7%) clinically significant adverse effects to midazolam occurred. The reactions were aggressiveness, euphoria, depression, and intense hiccups (singultus) despite low doses of midazolam. The severest forms of these adverse effects to midazolam could be successfully treated with intravenous infusion of flumazenil (0.25-0.5 mg intravenously). CONCLUSION: Adverse effects including aggressive, euphoric, or depressive behavior can occur in a significant proportion (6%) of patients with cardiac conditions undergoing TEE after intravenous administration of midazolam. The administration of the benzodiazepine antagonist flumazenil can reverse the adverse effects to midazolam successfully.

Adult↗

Evaluation of Hemodynamic Determinants of Quantitative Tissue Doppler Echocardiography in the Assessment of Left Ventricular Function.

The aim of the present study was to determine whether quantitative tissue Doppler echocardiography has a role in the assessment of left ventricular hemodynamics. Thirty patients with suspected or known heart disease, but no wall motion abnormalities, took part in the study. Quantitative tissue Doppler echocardiography was performed using new software for digital analysis of the tissue Doppler signal. Average systolic subendocardial (S1), subepicardial (S2), and transmural (S3) wall velocity data were obtained from the inferoposterior wall and compared with the hemodynamics, including high fidelity pressure readings. S1 and S3 rates were found to be most reliable, being directly related to the peak rate of left ventricular pressure rise (dP/dt(peak)) and inversely to systemic vascular resistance (SVR) and resistance index (SVRI). The best correlation was between S1, dP/dt(peak), and SVRI (multiple regression analysis: r = 0.76, P < 0.0001; simple regression analysis relating S1 to dP/dt(peak)/SVRI: r = 0.77, SEE = 0.25, P < 0.0001). Thus, wall velocity indices as defined in this study have promise to become helpful in guiding the therapeutic modulation of inotropy and afterload in patients with heart failure.

Journal Article↗

Left Ventricular Thrombus After Pregnancy: Choice of Surgical Access Using Dynamic Three-Dimensional Echocardiography.

Two idiopathic thrombi loosely attached to the left ventricular wall were detected by dynamic three-dimensional echocardiography. Because the thrombi were shown to be lobulated and extremely mobile, urgent surgical treatment was mandatory. Three-dimensional image reconstruction enhanced appreciation of left ventricular thrombi by enabling accurate imaging of the spatial relationship between the thrombus, the myocardial wall, and the valvular apparatus, so that the most advantageous surgical access could be chosen. (ECHOCARDIOGRAPHY, Volume 13, May 1996)

Journal Article↗