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V Jezek

Publications and source records attributed to V Jezek.

At least 37 records · Page 2Linked to original sources
PubMed1988

Doppler echocardiography in the diagnosis of pulmonary hypertension.

Review of the current state of knowledge about Doppler diagnosis of pulmonary hypertension is presented. The authors compare the findings of numerous studies with their own data and analyse the causes of discrepancies and controversies that have remained to date. Doppler estimation of mean pulmonary artery pressure (PAP) using acceleration time (ACT) measurement in the right ventricular outflow tract or main pulmonary artery has been shown to correlate closely with simultaneously measured values of PAP both at rest and during exercise (r = -0.92 and -0.94, respectively). ACT values show sufficient sensitivity for the detection of pulmonary hypertension (89%), at maximum (100%) specificity. However, Doppler values not obtained simultaneously do not necessarily correlate with PAP in view of rapid physiological variations of PAP. For everyday diagnostic practice in cardiology, prediction based upon mere qualitative estimation of the type of velocity curve seems sufficient. Doppler diagnosis of pulmonary hypertension, little demanding on both technical skills and equipment, is gaining a priority status among the non-invasive methods available.

Echocardiography, Doppler↗
PubMed1988

Assessment of stroke volume and cardiac output by Doppler echocardiography.

The authors used the pulse and continuous-wave Doppler technique to perform 51 measurements of stroke volume and cardiac output in 37 persons. Results were compared with those obtained using Fick's principle of thermodilution (immediately subsequent or simultaneous). Regression analysis showed a close correlation between Doppler and haemodynamic values - r = 0.86 for stroke volume and 0.94 for cardiac output (p less than 0.001). Using the paired t-test, the methods did not differ significantly. Standard deviation of Doppler stroke volume values from reference haemodynamic values was 10%, and only two measurements differed by more than 25%. Doppler determination of cardiac output can be therefore recommended as an alternative method in patients with high-quality echo Doppler recordings.

Adult↗
PubMed1986

Comparison of M-mode echocardiography and angiography in the evaluation of left ventricular hypertrophy.

The authors analysed in a group of 82 patients with a symmetric left ventricle and a homogeneous ventricular wall thickness the reliability of M-mode echocardiography in recognizing left ventricular hypertrophy. In concentric hypertrophies, a sufficient diagnostic criterion is ventricular wall thickness. Measurement of the interventricular septum offers a better correlation with angiographic values (r = 0.609, p less than 0.001) than measurement of the posterior wall (r = 0.358, p less than 0.01); a correct diagnosis can be determined in 84%. In excentric hypertrophies, the hypertrophy must be assessed on the basis of calculating the left ventricular mass. The most accurate of echocardiographic methods proved to be the calculation according to the authors' own formula (r = 0.760, p less than 0.001), which recognizes left ventricular hypertrophy correctly in 85%. The diagnostic correctness of Teichholz' formula is 80% and of the cubic formula 74%. Fortuin's equations proved to be of no value for documenting ventricular hypertrophy. In a group of 13 patients with hypertrophic cardiomyopathy, the correlation between angiographic and echocardiographic values of the left ventricular mass was very low (r = 0.534, p = 0.05).

Angiography↗
PubMed1986

Changes in the left ventricular function after application of contrast media.

The authors studied at repeated ventriculographic examinations the changes in the left ventricular function after application of routinely used ionic contrast medium and of newer nonionic medium. They demonstrated that ionic medium does not significantly change the left ventricular volume and ejection fraction, but influences the left ventricular diastolic function. Nonionic contrast material does not significantly change the left ventricular function. The mechanism of side-effects of contrast agents and possible indications for the application of nonionic contrast media are discussed.

Contrast Media↗
PubMed1986

A critical appraisal of M-mode echocardiography in mitral stenosis.

The reliability of M-mode echocardiography in confirming mitral stenosis and in assessing its severity was tested in 39 patients with mitral stenosis. None of the conventional echocardiographic signs of mitral stenosis is absolutely reliable. Unless at least 2 signs are combined, the diagnosis is not conclusive (sensitivity = 0.97, specificity = 1.00). Of a number of echocardiographic parameters and equations recommended (as tools) to determine the severity of mitral stenosis, the early diastolic velocity of anterior leaflet opening (EF) is the only one with a statistically significant relationship to the mitral valve area (MVA) calculated by Gorlin (r = 0.712, p less than 0.001), and this only in uncomplicated unoperated mitral stenoses, but not in mitral restenoses and combined mitral defects. Even the recently published Seitz's equation for calculating MVA from echocardiographic data is not reliable. M-mode echocardiography is an excellent technique for the primary diagnosis of mitral stenosis. However, it is not suitable to even an approximate assessment of its haemodynamic severity.

Calcinosis↗
PubMed1986

The importance of quantitative Doppler in assessment of mitral stenosis.

Duplex Doppler echocardiography with high pulse repetition frequency was used to study: group A - 7 patients with mitral stenosis (MS) during cardiac catheterization, and group B - 26 patients with MS in whom the Doppler examination was performed 24 h-3 months prior to catheterization. Using the peak flow velocity within the stenotic flow jet, the pressure drop and mitral valve area (MVA) were calculated and compared with data obtained invasively. The inter-observer variability of the two parameters was 12% and 5%, respectively. The correlation between Doppler pressure drop and invasive measurement was excellent in group A (r = 0.83), while less close in group B (r = 0.71). However, using only MVA estimates (group B), it was possible to recognize most of MS with catheterization MVA less than or equal to 1.0 cm2/m2 (sensitivity and predictive value both of 90%). Therefore, even nonsimultaneous quantitation of MS seems valuable in pre-operative patient evaluation, adding a new information to hitherto existing echocardiographic criteria.

Cardiac Catheterization↗
PubMed1984

The prognosis and development of pulmonary hypertension in idiopathic diffuse interstitial lung fibrosis.

The prognosis of patients with idiopathic diffuse interstitial lung fibrosis is extremely variable and depends mainly on the presence and degree of pulmonary arterial hypertension. The incidence of pulmonary arterial hypertension in idiopathic diffuse interstitial lung fibrosis is not exactly known. We concluded from our study that in nonselected symptomatic patients about 50% have normal pulmonary arterial pressure and that advanced pulmonary arterial hypertension (over 30 mmHg) is present in about 10% of cases. The development of pulmonary arterial hypertension in idiopathic diffuse interstitial lung fibrosis, though generally slow, is very different in individual cases. We noted fast development of advanced pulmonary arterial hypertension within 2-3 years as well as stabilized normal pressure for 20 years or more. Further behaviour of pulmonary arterial pressure may not be safely predicted from any value in a first functional examination except in patients with initial advanced pulmonary arterial hypertension; they all either maintain or even increase their pulmonary arterial pressure and their 3-year mortality is over 50%. It is concluded that the knowledge of haemodynamic data not only improves our understanding of idiopathic diffuse interstitial lung fibrosis, but also enables us to determine the prognosis with a fair amount of accuracy.

Adult↗
PubMed1982

TSH stimulation and other ways to increase the uptake in normal and tumorous thyroidal tissue.

The use of bovine TSH is still the most important means for increasing the radioiodine uptake in functionally active tissue. The increase is more marked in normal thyroid tissue (where 2.5 fold increase of the initial value can be expected); but the tumorous tissue reacts to the stimulation, though less substantially (mean increase to 1.5). In intact thyroid gland the increase of uptake is more pronounced with lower uptake in the remaining thyroid tissue; in functionally active tumor this relation cannot be proved. With very low uptake in the tumorous tissue (below 2.5%/24 h) the chance to achieve practically significant increase is negligible. The complications with TSH administration appear especially with repeated application, the proportion of more serious side effects being low. The use of diuretic regime with the iodine depletion simultaneously with TSH stimulation is rather pretentious for the patient; it substantially increases the uptake in the tumorous tissue (again to 2.6 times), although more markedly decreases the iodine excretion in the urine what leads to higher danger of complications caused by radioiodine therapy. The use of TSH stimulation to increase the uptake in the tumorous tissue had not yet been shown to be useful.

Humans↗