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S Effert

Publications and source records attributed to S Effert.

At least 55 records · Page 3Linked to original sources

Effects of heart rate changes on left ventricular volume and ejection fraction: a 2-dimensional echocardiographic study.

The influence of heart rate on left ventricular (LV) volumes and ejection fraction (EF) using 2-dimensional (2-D) echocardiography during atrial pacing was analyzed. The study was performed in 13 normal control subjects, 23 patients with coronary heart disease and 8 patients with dilated cardiomyopathy. An electronic sector scanner (2.25 MHz, 84 degrees) was used. Under constant scanning of the left ventricle, heart rate was increased, in steps of 20 beats/min, from 80 to 140 beats/min. The 2-D echocardiograms were stored on videotape and analyzed off-line. The end-diastolic and end-systolic volumes (EDV and ESV) were determined using a disc method. Stroke volume (SV) and EF were calculated. Constant LV scanning was possible during atrial stimulation, as shown by the analysis of simultaneously recorded 2-D echocardiograms and cineventriculograms at different heart rates, revealing a constant position of the echocardiographic transducer. Simultaneous recordings of cineventriculography and 2-D echocardiography at 80 and 120 beats/min showed that despite differences in absolute values, percent changes of LV volumes and EF determined with both methods were similar. Thus, changes of LV function can be analyzed by 2-D echocardiography. In normal control subjects, an increase in heart rate of 10 beats/min reduced EDV by 4 ml, ESV by 2 ml, SV by 2 ml and EF by 1%, corresponding to percent reductions of 4, 2, 5 and -2%, respectively. In contrast, the absolute decreases in the patients were 6 ml, 1 ml, 5 ml and 2% and the percent changes 2%, 1%, 8% and 5%.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

On-line monitoring of multiple precordial leads in high risk patients with coronary artery disease--a pilot study.

In a pilot study, a computerized precordial mapping system monitored ischaemia on-line in 50 patients (40 with acute myocardial infarction and 10 with unstable angina, class IV (Canadian Cardiovascular Society). All had ST-segment depression or elevation greater than or equal to 0.2 mV in one or more precordial leads when they were admitted to our coronary care unit. After preliminary precordial mapping with 48 electrodes to localize the area of ischemia, 5 to 8 electrodes were placed in and around the centre of the ST-segment changes. The patients were monitored between 24 and 48 h (mean 35.5 h). To minimize problems caused by artifacts, ECG signal quality was improved by the averaging technique. Thereafter, the ECG was evaluated with respect to Q and R wave amplitudes and ST-segment changes. At 3 min intervals, Q and R wave amplitudes and ST segment elevations or depressions, summed for all leads were plotted as a histogram. ECG signal quality was excellent and there were no problems with the attachment of the electrodes. All patients were treated with nitroglycerine intravenously and high doses of heparin and, in several cases, nifedipine as well. Some patients received thrombolytic therapy with streptokinase. Despite therapy, 21 ischaemic attacks were documented in five patients. Seventeen attacks were seen in patients with acute infarction but who were not treated with streptokinase. All attacks were accompanied by chest pain. The duration of ischaemia ranged from 18 to 87 min. Several attacks were stopped immediately by therapy.(ABSTRACT TRUNCATED AT 250 WORDS)

Angina, Unstable↗

Sensitivity and specificity of two-dimensional echocardiography in detection of impaired left ventricular function.

The purpose of the study was to determine the sensitivity and specificity of two-dimensional echocardiography (2dE) in the detection of impaired left ventricular function, compared with cineventriculography (CVG). Apical two-dimensional echocardiograms were performed in 110 patients undergoing heart catheterization for the evaluation of clinically suspected coronary heart disease (50 patients), valvular heart disease (38 patients) and congestive cardiomyopathy (22 patients). The left ventricle was scanned in the RAO-equivalent view; cineventriculograms were filmed in the 30 degrees RAO projection. Left ventricular volumes at end-diastole (EDV) and end-systole (ESV) were determined using a disc method; stroke volume (SV) and ejection fraction (EF) were calculated. Based on normal values, the sensitivity, specificity, and predictive accuracy were determined for two-dimensional echocardiography. For EDV, the sensitivity was 80%, specificity 88% and (+) predictive accuracy 86%. The left ventricular ejection fraction was 57.8 +/- 17.2% with CVG and 53.8 +/- 15.6% with 2dE in patients with coronary heart disease, 24.9 +/- 10.5% with CVG and 25.2 +/- 11.1% with 2dE in patients with congestive cardiomyopathy, and 61.1 +/- 13.9% with CVG and 54.2 +/- 9.1% with 2dE in patients with valvular heart disease. Sensitivity was 81%, specificity 100%, and (+) predictive accuracy 100%. The study demonstrates that impaired left ventricular function can be detected by 2dE with high sensitivity and specificity. Thus, 2dE seems to be suitable screening method for evaluation of left ventricular function.

Adult↗

[Transluminal angioplasty--unstable angina, fresh infarct].

Transluminal coronary angioplasty is successfully used in stable and unstable angina. Out of 107 patients admitted with unstable angina 28% were treated medically, 24% operatively and 48% by angioplasty. In a total of 116 patients the stenosis diameter was enlarged from 75.0 +/- 11.0% obstruction to 25.1 +/- 16.4% (improvement 49.9 +/- 16.5%) without differences between concentric and eccentric or right and left coronary stenosis. In 11 out of 22 patients with total coronary occlusion of recent origin the vessel was reopened by the balloon and enlarged to a resting stenosis of 22.3 +/- 16.4%. There were no differences in the success- and the complication rate between stable and unstable angina. After successful thrombolysis residual stenoses greater than 50% are dilated during the same session. In a randomized prospective study 51 patients were dilated immediately (group I) and 48 patients (group II) treated conservatively. In group I the reinfarction- and the cardiac death-rate was two patients compared to seven patients in group II. After four weeks there was one reocclusion (3%) compared to five (17%) and a residual stenosis of 31.9 +/- 24.4% versus 78.0 +/- 15.2%. Angioplasty can be used with good results and a low complication rate in unstable angina and following successful thrombolysis.

Aged↗

[Echocardiographic monitoring of acute myocardial infarct following intracoronary streptolysis treatment].

Two-dimensional echocardiography is helpful in the detection of wall motion abnormalities and in the evaluation of time courses of regional function due to interventions. Of 301 patients with acute myocardial infarction treated with selective intracoronary infusion of streptokinase, 229 (76%) revealed a totally occluded infarct related vessel at the first angiography. In 64 patients a two-dimensional apical long-axis view of good technical quality could be obtained after admission, on the 1st, 2nd and 3rd day and again in the 4th to 6th week and the 9th to 14th month after the acute intervention. The collective was divided into two subgroups according to the different time interval between the beginning of symptoms of infarction and the reopening of the occluded vessel. 35 patients had a total time of occlusion of less than 4 hours (group A), while in 29 others this time exceeded 4 hours or thrombolysis was unsuccessful (group B). Using a computer system, the center of gravity of the end-systolic frame of the left ventricle was used as an inner fix point. 10 end-systolic and end-diastolic area segments were constructed. Regional wall motion was determined as a percentual change of the enclosed area, normalized to the end-diastolic area (% delta F). The ejection fraction was calculated using a disc method. In group A the ejection fraction increased from initially 46 +/- 9% to 51 +/- 8%, 52 +/- 8% (p less than 0.05) and 53 +/- 8% (p less than 0.01) on the 1st, 2nd and 3rd day, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Cardiac Output↗

[Diagnostic value of changes in the R-amplitude of the stress ECG compared to the ST-segment depression in patients with significant coronary vessel stenoses].

Exercise electrocardiograms were registered in 50 patients with significant coronary artery stenosis (lumen narrowing greater than or equal to 70%) and in 20 controls without cardiac disease using automated registration (mapping). All patients had a normal ECG at rest and typical angina. ST-segment depression of more than 0.1 mV 60 ms after the J-point in three adjoining leads and in three consecutive registrations could be shown in 46 of the 50 patients (sensitivity 92%) with coronary artery disease, however in no proband of the control group. The sum of the R-amplitudes in the precardiac leads (sigma R) was calculated before and during maximal exercise and six minutes after. Diminution of R-wave amplitudes during exercise was seen in both groups. Six minutes after exercise initial values had been nearly regained. Differentiation of both groups using R-wave amplitudes after exercise thus was impossible. Even using only leads with ST-segment lowering during exercise, a slight increase of R-amplitudes could be measured in only one case. In all other patients R-wave amplitudes diminished also in the ischaemic area with increasing ST-segment depression. RS-inversion was shifted towards the cardiac apex. Thus an increase of R-wave amplitudes indicating coronary arterial disease does not occur in unipolar chest leads in patients with significant coronary artery stenosis and ST-segment lowering during exercise.

Adult↗

[Emergency diagnosis of acute aortic insufficiency using one- and two-dimensional echocardiography].

Acute aortic valve insufficiency generally leads to an emergency situation followed by surgery. Using echocardiography pathological findings of the aortic valve or the ascending aorta leading to acute aortic insufficiency could be differentiated exactly and rapidly in 12 out of 13 cases. Dissecting aneurysms of the aorta and bacterial endocarditis were the most frequent causes (50 and 43%). Our results showed clear-cut superiority of combined use of one- and two-dimensional echocardiography to M-mode techniques. Both methods complement each other with their advantages and disadvantages. With their help recognition of causes of aortic insufficiency is possible more rapidly, safer and with a higher sensitivity than with the M-mode method alone. Invasive diagnostics may thus become unnecessary in the appropriate cases.

Adult↗

Percutaneous transluminal coronary angioplasty in patients with stable and unstable angina pectoris: analysis of early and late results.

Percutaneous transluminal coronary angioplasty (PTCA) was performed in 50 patients with stable and in 50 patients with unstable angina pectoris, each patient showing an isolated stenosis of more than 80% of the cross-sectional area of a single coronary artery. The technical success rate was 66% in the stable groups (26 of 37 patients [70%] with left anterior descending artery [LAD], 7 of 12 patients [58%] with right coronary artery [RCA]) and 74% in the unstable group (27 of 34 patients [79%] with LAD, 10 of 15 patients [67%] with (RCA). The increase in stenotic area in the unstable group exceeding that in the stable group for LAD stenoses (41.5 +/- 15.1% vs 32.3 +/- 14.5%, p less than 0.03), while in RCA stenoses the results in the stable group were better (45.1 +/- 17.6% vs 32.7 +/- 12.3%, n.s.). One acute vessel occlusion necessitating an emergency bypass operation occurred in each group (2%). The patient in the stable group died (total mortality rate 1%). Sixty-three of the successfully treated patients were routinely restudied 6 months later. According to clinical symptoms, 23% of the stable and 36% of the unstable group were in functional classes III and IV. From the anatomical viewpoint, a restenosis (greater than 85%) was found in 17% of the stable and in 24% of the unstable group. A further spontaneous decrease (greater than 10%) of the vessel obstruction was found in 47% of the stable group and in 12% of the unstable group.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

New developments in medical-surgical treatment of acute myocardial infarction.

Selective intracoronary thrombolysis with streptokinase was successful in 72 of 84 (86%) patients admitted to the hospital with definitive signs of acute transmural myocardial infarction due to complete occlusion of either the left anterior descending coronary artery, the right coronary artery, or the circumflex artery. The average time between onset of acute symptoms and medically induced reperfusion was 241 +/- 90 minutes (SD). Reperfusion resulted in prompt relief of pain, regression of cardiogenic shock, and normalization of electrocardiograms. Follow-up treatment was either medical or surgical. The 32 medically treated patients had a high reocclusion rate, with 6 fatal (19%) and 9 nonfatal (28%) reinfarctions. In order to the reduce the risk of reinfarction, additional simultaneous transluminal balloon angioplasty was done in a recent series of patients with stenoses accessible to this technique. The best early and long-term results were achieved in 17 patients who underwent coronary artery bypass grafting within three days after successful thrombolysis. There was no operative mortality, and subsequent bleeding has not been a problem. It is concluded that early operation is the treatment of choice in all patients suitable for such intervention who have undergone successful intracoronary thrombolysis within 4 hours after onset of acute myocardial infarction. Late coronary bypass operation should be reserved for symptomatic patients who have definitive signs of infarction in spite of successful thrombolysis.

Aged↗

[2-dimensional echocardiography in acquired heart valve defects].

A fundamental improvement in the diagnosis of acquired valvular defects has been achieved by the introduction of two-dimensional echocardiography. For the first time, it has now become possible to visualize the underlying morphological changes direct and true to anatomy. Additional information is supplied by a detailed study of the dynamics of the affected valve. At present, limited information only can be obtained in respect of the haemodynamic severity of the defect. In the near future, however, we may expect advances also in quantitative respect, from a combination of this method with Doppler echocardiography or contrast echocardiography.

Aortic Valve Insufficiency↗

[Quantification of the function of the left ventricle using 2-dimensional echocardiography].

Left ventricular volumes and the ejection fraction can be determined by two-dimensional echocardiography. Because of methodological problems, cineventriculographic normal values can not be transferred to two-dimensional echocardiography. Therefore, normal values for two-dimensional echocardiographically determined left ventricular volumes and the ejection fraction were established in 55 normal controls. Basing on these volumes, the sensitivity and specificity of two-dimensional echocardiography for detection of impaired left ventricular function was analysed and compared with results from cineventriculography. Sensitivity for detection of a reduced ejection fraction was 84%, specificity 89% and predictive accuracy 98%. Thus, two-dimensional echocardiography can be used as a screening method for analysing left ventricular function. Analysis of beat-to-beat variation revealed that for two-dimensional echocardiography 3 consecutive beats should be analysed because evaluation of 5 instead of 3 beats increased reliability only by less than 1%. It was necessary to analyse the day-to-day variations. To separate a random error from a non-random error for an individual change, an absolute change of volumes of more than 10-12% and of ejection fraction of more than 10% had to be observed. Group changes can of course be smaller and yet significant. Intraobserver variation was not significant and below 5%. However, interobserver variability must be considered. This depends on observer experience. For a 4-chamber view no significant variability was observed, but for the RAO-equivalent view the observer variation was significant for end-diastolic and end-systolic volume. For the ejection fraction no significant difference was found. Two-dimensional echocardiography can be used for pharmacodynamic studies if percentage changes instead of absolute changes are listed.

Cardiac Output↗

Echoventriculography -- a simultaneous analysis of two-dimensional echocardiography and cineventriculography.

Two-dimensional echocardiography underestimates left ventricular volume compared with cineventriculography. To exclude the influence of difference in heart rate, blood pressure, respiration phases and any effect of the contrast material on left ventricular function, simultaneous studies of two-dimensional echocardiography and cineventriculography-echoventriculography were performed in 46 patients. Apical two-dimensional echocardiograms in the right anterior oblique (RAO) equivalent view were recorded before and during cineventriculography in the 30 degrees RAO projection. End-diastolic and end-systolic volumes (EDV and ESV) were calculated using a disc method with a semiautomatic computer system. The echo transducer position relative to the left ventricular apex and long axis was analyzed. For EDV determined by two-dimensional echocardiography and cineventriculography, the linear regression equation was y = 0.659x + 0.8, SEE = +/- 26.2 ml, r = 0.907. For ESV, the regression equation was y = 0.571x + 17.8, r = 0.938, SEE = +/- 18.6 ml, and for ejection fraction (EF) it was y = 0.606x + 13.0, r = 0.803, SEE = +/- 9.1%. Injection of contrast material resulted in only a small increase of stroke volume, caused by an increase of EDV as analyzed by echoventriculography. In all but two patients, the transducer position was found to be anterior and superior to the left ventricular anatomic apex, as evaluated by filming the echo transducer position during cineventriculography in 46 patients in the 30 degrees RAO projection and in 15 patients consecutively in the 60 degrees left anterior oblique and 30-40 degrees cranial projections. Thus, tangential cuts of the ventricle resulted in underestimation of diameters, long axis and ventricular volumes. These methodologic problems are exacerbated by slice-thickness artifacts. Furthermore, different outlining of left ventricular contour -- outer border of ventricular trabeculae for cine ventriculography and inner border for two-dimensional echocardiography -- seemed to result in underestimation of volume by echocardiography.

Adult↗

Percutaneous transluminal coronary angioplasty in patients with unstable angina.

A comparison of clinical data has shown that percutaneous transluminal coronary angioplasty can be performed with equally good results in unstable and stable angina pectoris. Transluminal coronary angioplasty and coronary bypass surgery do not alter the natural progression of coronary atherosclerosis, but coronary angioplasty provides a real chance at least to postpone bypass graft surgery if not to provide lasting relief of angina.

Angina Pectoris↗

Emergency treatment of hypertensive crisis with sublingual nifedipine.

Sublingual nifedipine 20 mg as an emergency treatment for severe hypertension or hypertensive crisis in 30 patients gave an effective and gradual reduction in blood pressure. Side effects were rare and not severe. The heart rate remained fairly stable or sometimes even decreased. Thus, sublingual nifedipine may now be considered a reasonable first choice in the treatment of severe hypertension or hypertensive crisis.

Administration, Oral↗