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G Kronik

Publications and source records attributed to G Kronik.

At least 55 records · Page 3Linked to original sources
PubMed1982

[M-mode and two-dimensional echocardiography of heart valve prosthesis dysfunction].

The diagnostic efficacy of M-Mode and 2-d echocardiography for the detection of malfunctioning prosthetic valves was studied in twenty-nine patients with prosthetic valves and clinical deterioration. Echocaradiographic abnormalities were found in 8 of 12 patients with confirmed valve dysfunction; 30.8% of the cases had false negative echo tracings. In 17 patients with normal echocardiographic pictures of the valves another cause of clinical deterioration was found (congestive heart failure, pericardial effusion, aneurysm of aortic root). In this study M-Mode and 2-d echocardiography had an excellent diagnostic accuracy rate in distinguishing congestive heart failure from valve dysfunction. Comparing the data of M-Mode and 2-d registration, both methods are found to be complementary. A major advantage of the 2-d echocardiography is its enhanced spatial orientation, whereas M-Mode echocardiography enables better evaluation of valve movements and corresponding time intervals and recognition of quick movements and fibrillations.

Aortic Valve↗
PubMed1982

Glycosylated hemoglobins (GHb): an index of red cell survival.

Levels of glycosylated hemoglobins (GHb) are significantly (p less than 0.0005) lower in patients with hemolytic anemia (n = 20; mean = 3.9% +/- 0.1% SD GHb of total Hb) compared to patients with nonhemolytic anemia (n = 20; mean = 7.0% +/- 0.7% GHb) and normal controls (n = 30; mean = 6.7% +/- 0.7% GHb). A curvilinear correlation between GHb and red cell survival is demonstrable (n = 20;r2 = 0.88; p less than 0.001). Determination of GHb may be useful as a screening test for hemolytic anemia and for the evaluation of the degree of hemolysis, provided that diabetes mellitus can be excluded.

Adolescent↗
PubMed1981

[Thallium-201-myocardial imaging after high dose dipyridamole (author's transl)].

Biphasic thallium-201-myocardial imaging was performed in 100 patients undergoing coronary angiography. The images were obtained in several views after the administration of dipyridamole (0.50 mg/kg body weight) and 4 hours later. 24 patients had normal coronary arteries or insignificant stenoses, in 74 patients a 70-percent or greater stenosis of one or more coronary arteries was present. 55 transmural myocardial scars were diagnosed by left ventriculography in 53 patients. The described method showed a sensitivity of 93 percent and a specificity of 96 percent in the detection of patients with significant coronary artery stenoses. Irreversible perfusion defects were found in 91 percent of myocardial scars, in additional 7 percent the scintigraphic defects were reversible. In patients with multivessel disease and transmural infarctions, only one third of non-infarction-related stenoses were recognized. The number of angiographically stenotic coronary arteries could be determined scintigraphically only in a minority of the cases. The regional sensitivity in the assessment of LAD and right coronary artery stenoses was higher than for the left circumflex artery (75%, 80%, and 48% resp.), the specificity was equally high for all three vessels (96%, 99%, 100%).

Coronary Disease↗
PubMed1981

[Diagnosis of atrial left-to-right shunts by cross-sectional contrast echocardiography (author's transl)].

We have used cross-sectional contrast echocardiography with peripheral venous injection in 3 groups of patients: A) 23 patients with atrial septal defect (ASD); B) 19 patients with various forms of heart disease, but no evidence of ASD; C) 11 patients with proven interatrial communication, but no significant left-to-right shunt. The contrast studies were performed with a mechanical sector scanner and were evaluated retrospectively but "blindly", i.e. without knowing the patient's name and diagnosis and without knowing that part of the echocardiogram, which had been recorded before injecting contrast. The sound track of the video recorder was turned off. Left-to-right atrial shunting could be demonstrated in 20/23 (87%) patients with ASD, and in all 14 patients in whom both the parasternal and the apical examination technique had been used. The left-to-right shunt was seen as a stream of contrast-free blood flowing from the left atrium into the right atrium and washing away the contrast echoes at the site of the defect. This "negative contrast" or "wash-out" effect was accompanied by turbulences in the right atrium. All 22 patients with this sign had interatrial communications, but interestingly there were 2 patients in whom no definite left-to-right shunt could be demonstrated by oxymetry. Thus the "wash-out" phenomenon seems to be specific for a defect, but not necessarily a significant left-to-right shunt. Right-to-left atrial shunts were diagnosed in 65% of the ASD group. A left-to-right or right-to-left shunt was never diagnosed in any of the control patients. Seemingly turbulent blood flow, the intermittent appearance of contrast-free blood (presumably from the coronary sinus or the inferior vena cava) in the right atrium and a "wash-out" effect at the site of the entry of the inferior vena cava are potential sources of error. However, our blind analysis has shown that these pitfalls can be avoided.

Diagnosis, Differential↗
PubMed1980

[Contrast echocardiography in patients with insignificant interatrial communications (patent foramen ovale) (author's transl)].

Peripheral M-mode contrast echocardiograms at rest and during the Valsalva manoeuvre were performed in 9 patients with haemodynamically insignificant interatrial communications. Contrast echoes appeared in the left heart in all 4 patients with elevated right ventricular pressure, but also in 3 out of the 5 patients with normal right-side pressures. Thus, a positive contrast echocardiogram, while definitely proving the presence of an intracardiac communication, does not necessarily mean that the defect is haemodynamically significant. The ability to detect a patent foramen ovale non-invasively by contrast echocardiography may be useful in patients with suspected paradoxical embolism.

Blood Pressure↗
PubMed1980

[Biphasic 201thallium scintigraphy after dipyridamole in mitral valve diseases (author's transl)].

The results of biphasic 201thallium scintigraphy after dipyridamole i.v. could neither prove nor exclude the presence of small focal lesions in the myocardium of 17 patients with mitral valve diseases. The frequent finding of a decrease in activity in the anterolateral myocardium is probably due to a relative increase in activity in the region of the inferior wall with superimposed areas of the papillary muscle and right ventricular myocardium. If the right ventricle is visualized in stress- or redistribution images, an increase in mean pulmonary artery pressure can be accepted. According to Cohen's criteria, a grade 2 or 3 virtually proves the existence of pulmonary hypertension, a grade 1 makes this finding rather probable. The possibility of pulmonary hypertension can not be excluded if the right ventricular myocardium is not visualized.

Adult↗
PubMed1979

[The diagnostic accuracy of the dipyridamole test in coronary heart disease (author's transl)].

The diagnostic accuracy of the dipyridamole test in provoking coronary insufficiency was investigated in 79 patients with chest pain and the results were compared with the findings on angiography and exercise electrocardiogram. 58 patients had documented severe coronary artery stenosis, 21 had patent coronary vessels (cardiomyopathy 8, aortic stenosis 1, ectopic origin of coronary artery 1, normal 11). Anginal pain after dipyridamole was a non-specific finding. Approximately half the subjects in whom coronary insufficiency would be expected according to the coronary angiographic and ventriculographic findings evidenced ischaemic ST-segment depression after dipyridamole, which was comparable to the number of positive exercise electrocardiograms. In 23 patients, most of whom had shown an inadequate frequency response during the initial exercise test, ergometry was repeated after the administration of dipyridamole. This resulted in an increase in ischaemic ECG response from 26 to 70%. It is concluded that a stress test combining dipyridamole and submaximum exercise increases the incidence of ischaemic ST-segment depression in comparison with ergometry alone. Anginal pain without ST-segment depression proved to be without diagnostic value.

Adult↗
PubMed1979

Contrast M-mode echocardiography in diagnosis of atrial septal defect in acyanotic patients.

Contrast echocardiograms during normal quiet respiration and during the Valsalva maneuver were performed in 15 patients with atrial septal defect (ASD) by injecting saline solution into an antecubital vein. Contrast shunting (the appearance of contrast echoes in the left heart) was observed not only in four patients with severe pulmonary hypertension (group 2), but also in 11 patients with uncomplicated ASD (group 1). Contrast shunting was prominent in all group 2 patients. In group 1, contrast shunting was sometimes subtle and difficult to recognize, but at other times was very obvious and similar to the findings in group 2. Contrast shunting was generally more pronounced during the Valsalva maneuver than during normal respiration, although there were exceptions. The amount of contrast appearing in the left heart did not correlate with the size of the defect. Small right-to-left shunts which are clinically insignificant but detectable by contrast echocardiography are present, or can be provoked by the Valsalva maneuver, in most patients with ASD. Contrast echocardiography is a useful, noninvasive method to detect interatrial communication, even in acyanotic patients.

Echocardiography↗
PubMed1979

Comparative value of eight M-mode echocardiographic formulas for determining left ventricular stroke volume. A correlative study with thermodilution and left ventricular single-plane cineangiography.

Sixty-six consecutive patients without left ventricular volume overload, significant arrhythmia or significant pericardial effusion were examined by M-mode echocardiography immediately before diagnostic left- and right-heart catheterization. Using various echocardiographic measurements, left ventricular stroke volume (SV) was calculated according to eight different echocardiographic formulas (SVE) that have been proposed previously. At catheterization SV was also determined by thermodilution (SVT) and by single-plane left ventricular cineangiography in the right anterior oblique projection (SVA). When comparing SVE with SVT, the four formulas developed to calculate mitral or aortic flow failed (r = 0.10 to 0.54). As expected, poor correlations (r = 0.22 to 0.47) were also found when formulas used to calculate ventricular volumes from the ventricular diameter or SV from the change in diameter (left ventricular formulas) were used in coronary patients with grossly asymmetrical ventricular contraction patterns. When the use of the left ventricular formulas was confined to patients with symmetrical or almost symmetrical contraction, two formulas yielded favorable correlations of r = 0.84, SEE = 12.7 ml and r = 0.86, SEE = 12.2 ml, respectively. These correlations were comparable to the correlation between our two invasive reference techniques (r = 0.81; SEE = 12.2 ml). The comparison between SVE and SVA confirmed the results of the thermodilution study, though the correlations were generally weaker. We conclude that the formula of Teichholz et al., which was the best of all tested formulas, may be used to obtain a clinically useful estimate of SV in patients in whom symmetrical or almost symmetrical left ventricular contraction can be anticipated.

Aortic Valve↗
PubMed1979

[Echocardiographic diagnosis of subpulmonic obstruction in hypertrophic cardiomyopathy (a case report) (author's transl)].

The echocardiogram of a patient presenting with a systolic ejection murmur and ECG evidence of left ventricular hypertrophy revealed asymmetric septal hypertrophy but no abnormal systolic anterior motion of the mitral valve as in IHSS. Her pulmonary echo disclosed small A waves, partial valve closure in early systole and coarse systolic fluttering. This motion pattern--which is similar to that of patients with infundibular pulmonary stenosis and which resembles the aortic valve motion pattern in discrete subaortic stenosis--led us to the diagnosis of hypertrophic cardiomyopathy with subpulmonic obstruction, which was later confirmed by cardiac catheterization.

Aortic Valve↗
PubMed1978

[The dependability of noninvasive stroke volume measurements with impedance cardiography].

In 33 patients 110 comparative measurements of stroke volume were performed by the thermodilution method and impedance cardiography during rest and various hemodynamic interventions. Agreement was moderate not allowing accurate estimation of the stroke volume in an individual patient. However, impedance cardiography proved useful in predicting acute changes in stroke volume or cardiac output exceeding 10% of control values.

Adult↗
PubMed1978

[Noninvasive determination of myocardial function in infarct patients].

In a prospective study, the regional ventricular function was assessed by cross sectional echocardiography in 22 patients with coronary heart disease. When compared with angiocardiography, cross sectional echocardiography has proven to be a valuable tool for the evaluation of regional ventricular function.

Angiocardiography↗