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Biomedical subjects

W G Daniel

Publications and source records attributed to W G Daniel.

At least 163 records · Page 9Linked to original sources
PubMed1990

[Acute anterior wall infarct with intractable ventricular fibrillation: successful therapy by recanalization of a left anterior descending coronary artery occlusion].

A 35-year-old male patient was admitted to the intensive care unit of a community hospital with an acute anterior myocardial infarction complicated by initial recurrent episodes of ventricular fibrillation and successful resuscitation. Persistent malignant ventricular arrhythmias during the following days necessitated external defibrillation approximately 250 times. The patient was transferred to the Hannover Medical School, where the occluded left anterior descending coronary artery was successfully recanalized. Eight days later, the malignant ventricular tachyarrhythmias ceased and after 59 days of hospitalization the patient could be discharged in stable condition.

Adult↗
PubMed1989

Low dose urokinase preactivated natural prourokinase for thrombolysis in acute myocardial infarction.

By inducing minimal free-fibrinolytic activity with low dose urokinase, the lag phase of prourokinase can be overcome, and the rate of thrombolysis with this substance can be strongly enhanced. The thrombolytic potency of a combination of 250,000 IU of urokinase and 2 doses of prourokinase (4.5 or 6.5 megaunits) was evaluated in an open-label, nonrandomized dose-finding study. Thirty-one patients participated. With 4.5 megaunits of prourokinase (group 1, 15 patients) patency was demonstrated angiographically at 60 minutes in 33% while with 6.5 megaunits (group II, 16 patients) 75% patency was achieved (p less than 0.01). A second angiogram recorded 24 to 36 hours after thrombolysis revealed reocclusion in 60 versus 8% of primarily patent coronary arteries (p less than 0.05). Hemostatic monitoring in both groups revealed only slight to moderate consumption of fibrinogen (-9 vs -13%), plasminogen (-29 vs -34%) and alpha 2-antiplasmin (-59 vs -63%), and an increase in D-dimers, the split products of cross-linked fibrin, to a maximum of 1.008 +/- 1.211 vs 0.547 +/- 0.684 micrograms/liter. None of these differences was significant. Bleeding complications were more frequently observed in group II (13 vs 37%) (difference not significant), but were mild and related to puncture sites, except in 1 patient with mild oozing from the gum. No major hemorrhage was observed. These results suggest that low dose urokinase preactivation enhances the thrombolytic potency of prourokinase, without affecting its high fibrin specificity. Compared to previous studies using only prourokinase, low dose urokinase preactivation reduces by 50% the prourokinase dose as required for effective thrombolysis.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1989

Echocardiography in infective endocarditis: reassessment of prognostic implications of vegetation size determined by the transthoracic and the transesophageal approach.

In 105 patients with active infective endocarditis, disease-associated complications defined as severe heart failure (New York Heart Association class IV), embolic events and in-hospital death were correlated to the vegetation size determined by both transthoracic and transesophageal echocardiography. A detailed comparison between anatomic and echocardiographic findings, performed in a subgroup of 80 patients undergoing surgery or necropsy, revealed that true valvular vegetations can be reliably identified by echocardiography in the vast majority of patients; the detection rate was significantly higher for the transesophageal (90%) than for the transthoracic (58%) approach, particularly when infected prosthetic valves were evaluated. However, an accurate echocardiographic differentiation between true vegetations and other endocarditis-induced valve destruction (ruptured leaflets or chordae) is impossible. The correlation of vegetation size with endocarditis-associated complications showed that patients with a vegetation diameter greater than 10 mm had a significantly higher incidence of embolic events than did those with a vegetation diameter less than or equal to 10 mm (22 of 47 versus 11 of 58; p less than 0.01). Particularly for patients with mitral valve endocarditis, a vegetation diameter greater than 10 mm was highly sensitive in identifying patients at risk for embolic events. Vegetation size, however, was not significantly different in patients with and without severe heart failure or in patients surviving or dying during acute endocarditis. In addition, no significant correlation was found between vegetation size and location of endocarditis or type of infective organism.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1989

[High-dose single administration of isosorbide dinitrate: effect on diurnal distribution of transitory myocardial ischemia in patients with stable angina pectoris].

We studied the effect of a monotherapy of isosorbiddinitrate on symptomatic and asymptomatic ischemic episodes in 15 ambulatory patients with chronic stable angina pectoris, positive exercise test, and coronary stenosis greater than 70%. Transient ST-segment depression (greater than 0.1 mV for at least 1 min) was documented by 48-h Holter monitoring during a control period without anti-ischemic therapy and at the end of 14 days of treatment with 120 mg o.d. isosorbiddinitrate slow-release. In the control period, 68 asymptomatic and 28 symptomatic ischemic episodes were detected; most of the episodes occurred in the morning between 6.00h and 12.00h (41 episodes) and in the afternoon between 12.00h and 18.00h (36 episodes). Under anti-ischemic therapy the number of episodes and the total duration of ischemia was reduced by 46% and 53%, respectively (p less than 0.01). The anti-ischemic effect was most evident during the morning and the afternoon; the ischemic episodes during the evening and the night were not significantly diminished. It is concluded that in patients with stable angina pectoris a single high-dose of isosorbiddinitrate significantly reduces the number and duration of transient ischemic episodes during daily life.

Aged↗
PubMed1989

[The status of echocardiography within the scope of routine cardiologic diagnosis].

In particular since the introduction of the two-dimensional approach, echocardiography as a non-invasive and easily repeatable bedside-technique without side-effects plays a central role within the diagnostic tools of cardiology. The following applications of cardiac ultrasound are commonly accepted and sufficiently validated: Assessment of the size of cardiac chambers including qualitative and quantitative evaluation of left ventricular function, detection of pericardial effusion, diagnosis of intra- and extracardiac tumors and thrombi, analysis of complex congenital diseases. Without the use of Doppler, valvular regurgitations can only be suspected by indirect parameters; in contrast, stenotic lesions as well as a variety of other valve abnormalities (calcifications/partial rupture/prolapse/vegetations) can be diagnosed with a high accuracy. Transesophageal echocardiography guarantees not only an optimal imaging quality in virtually all patients, in addition, the technique allows the routine visualization of the thoracic descending aorta and the left atrial appendage which is of importance for the diagnosis of aortic dissection and isolated left atrial appendage thrombi. Transesophageal echocardiography is also superior to the conventional precordial approach concerning the assessment of prosthetic valve malfunction (in particular in mitral position) and endocarditis-associated abscesses. Today, the echocardiographic visualization of coronary arteries is without clinical relevance.

Aortic Dissection↗
PubMed1988

Reduced diastolic left ventricular posterior wall motion in patients with constrictive pericarditis--incidence, hemodynamic and clinical correlations.

In 24 patients with constrictive pericarditis proven by cardiac catheterization, the amplitude of diastolic left ventricular posterior wall motion was evaluated by M-mode echocardiography and compared to the results of 24 healthy volunteers. The amplitude was significantly less in constrictive pericarditis patients than in normal controls (0.3 +/- 0.2 mm versus 3.9 +/- 0.4 mm) (P less than 0.001). No constrictive pericarditis patient demonstrated a higher value than 2 mm whereas none of the healthy volunteers had an amplitude less than 3 mm. In 11 of 13 constrictive pericarditis patients who underwent pericardiectomy, an increase in amplitude was observed. In 6 patients the amplitude returned to normal limits after surgery. No significant correlation between the degree of heart failure or the level of left ventricular end-diastolic pressure and the reduction of the amplitude was found. In addition, the amplitude of left ventricular diastolic posterior wall motion did not allow a clear separation between patients who could be treated medically and those requiring pericardiectomy.

Adult↗
PubMed1988

Left atrial spontaneous echo contrast in mitral valve disease: an indicator for an increased thromboembolic risk.

The incidence of left atrial spontaneous echo contrast was evaluated in 52 patients with isolated or predominant mitral valve stenosis (Group 1) and 70 other patients who had undergone mitral valve replacement (Group 2). All patients were studied by conventional transthoracic and transesophageal two-dimensional echocardiography. Spontaneous echo contrast could be visualized within the left atrium in 35 Group 1 patients (67.3%) (including 7 patients with sinus rhythm) and 26 Group 2 patients (37.1%) (all with atrial fibrillation). Patients with spontaneous echo contrast had a significantly larger left atrial diameter and a greater incidence of both left atrial thrombi and a history of arterial embolic episodes than did patients without spontaneous echo contrast. Association between spontaneous echo contrast and left atrial thrombi and a history of arterial embolization (considered individually or in combination) showed a high sensitivity and negative predictive value. It is concluded that spontaneous echo contrast is a helpful finding for identification of an increased thromboembolic risk in patients with mitral stenosis and after mitral valve replacement.

Adult↗
PubMed1988

Effects of nifedipine and nitrates on coronary vasomotion.

The diameter changes of angiographically normal coronary arteries following vasodilator drugs were studied in 41 patients. In group 1 (22 patients) angiograms and plasma levels were obtained before as well as 10, 20 and 30 minutes after 20 mg nifedipine s.l. (15 patients) or placebo (7 patients). A cluster analysis allowed a classification of patients into group A (N = 4) and B (N = 11) according to the slope of plasma level increase. Plasma levels A versus B were 27.8 +/- 9.8/13.5 +/- 4.5 ng ml-1; P less than 0.05; 54.0 +/- 11.7/21.7 +/- 6.6 ng ml-1; P less than 0.001; 79.1 +/- 9.3/28 +/- 9.8 ng ml-1; P less than 0.001. Corresponding diameter changes A versus B were: 7.3 +/- 5.1%/-5.6 +/- 9.0%; P less than 0.01; 11.4 +/- 4.1%/-4.5 +/- 11.3%; P less than 0.01; 14.5 +/- 5.9%/0.5 +/- 13.6%; P less than 0.05. In group 2 (N = 19) angiograms were obtained before as well as 2, 4, 7 and 15 minutes after administration of 10 mg isosorbide dinitrate (N = 9) or placebo (N = 10). Coronary dilation ISDN versus placebo was: 2.4 +/- 3.6%/0.9 +/- 4.0%; NS; 10.6 +/- 5.1%/3.1 +/- 3.8%; P less than 0.001; 12.3 +/- 5.9%/-0.3 +/- 6.4%; P less than 0.005; 10.5 +/- 6.5%/-4.0 +/- 7.7%; P less than 0.005. These data indicate that the interindividual variations of changes in coronary lumen size are due to different slopes of plasma level increase, most likely due to different rates of drug absorption after sublingual administration of nifedipine.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Sublingual↗
PubMed1988

Evaluation of global and regional left ventricular function using two-dimensional and M-mode echocardiography in patients with an automatic implantable cardioverter defibrillator.

The effects of glued epicardial patch electrodes of the automatic implantable cardioverter defibrillator on the left ventricular function was studied by two-dimensional and M-mode echocardiography in 15 patients. Pre- and postoperative end-diastolic and end-systolic left ventricular cross-sectional areas were evaluated using planimetry. Regional left ventricular wall motion at the level of the left ventricular patch electrode was analyzed by two end-diastolic and end-systolic perpendicular axes. Left ventricular end-diastolic and end-systolic diameters as well as E-point-septal-separation and fractional shortening were analyzed using M-mode echocardiography. The mean time interval between preoperative echocardiograms and implantation of the automatic defibrillator was 0.3 X 1.3 (less than 1-2) months. Postoperative echocardiograms were recorded 6.6 +/- 6.9 (0.5-24) months after implantation of the device. There were no significant differences between pre- and postoperative mean values of end-diastolic and end-systolic areas and axes as well as M-mode echocardiographic parameters. Our data show that left ventricular patch electrodes do not significantly alter global or regional left ventricular function in patients after implantation of the automatic defibrillator.

Adult↗
PubMed1988

[Value of stress and long-term ECG in the diagnosis of silent myocardial ischemia in patients with coronary heart disease].

Symptomatic and asymptomatic myocardial ischemia during exercise testing and during daily activities (ST-segment analysis on 24-h Holter ECG) was studied in 109 patients with stable angina pectoris and proven coronary artery disease (coronary stenoses greater than 70%) (group I) and in 20 patients with angiographically normal coronary arteries or minimal changes (group II). During exercise testing, 94/109 (86.2%) group I patients and 6/20 (30%) group II patients showed ST-segment depression greater than or equal to 0.1 mV. During Holter ECG, transient ST-segment depression (greater than or equal to 0.1 mV; greater than or equal to 1 min) was observed in 76/109 (69.7%) group I patients and in 5/20 (25%) group II patients; all patients with positive Holter ECG also had a positive exercise tests result. Heart rate and exercise duration at the onset of ischemia during stress testing were useful parameters to estimate the incidence of ischemic episodes during Holter ECG. Patients with asymptomatic positive exercise tests showed a significantly higher percentage of asymptomatic ischemic episodes during Holter ECG than patients with a symptomatic positive exercise test (89% vs. 68% asymptomatic ischemic episodes; p less than 0.001). Therefore, in patients with coronary artery disease and stable angina pectoris, the exercise test provides information also about the activity of ischemic heart disease during daily activities.

Adult↗
PubMed1987

Renal infarction with fatal bleeding--an unusual complication of Candida albicans endocarditis.

A patient with mitral valve endocarditis due to Candida albicans infection is presented. Because of persistent fever and one episode of transient right-sided hemiparesis, the patient underwent mitral valve replacement. Two weeks after successful valve replacement, the patient suddenly developed acute abdominal pain and died before a surgical intervention could be initiated. Autopsy examination revealed a renal infarction in the lower part of the right kidney with a large rupture of the capsule and retroperitoneal bleeding. A myocotic aneurysm could not be detected. The clinical significance of renal infarction in infective endocarditis is discussed.

Adult↗
PubMed1987

Comparisons between diastolic fluttering and reverse doming of anterior mitral leaflet in aortic regurgitation.

In 27 patients with aortic regurgitation and nine patients with associated aortic stenosis, the incidence of reverse doming was studied by two-dimensional echocardiography and was compared with diastolic fluttering of the mitral valve. Reverse doming could be identified in four of six patients (66.7%) with mild aortic regurgitation and in 20 of 21 patients (95.2%) with moderate or severe aortic regurgitation (p less than 0.05). Fluttering of the anterior mitral leaflet was observed in all patients with mild aortic insufficiency and in 19 of 21 patients (90.5%) with moderate or severe aortic insufficiency. In patients with associated aortic stenosis, reverse doming was observed in three patients (33.3%), whereas fluttering was seen in six patients (66.7%). After aortic valve replacement, reverse doming persisted in one patient with a paravalvular leak. Reverse doming or fluttering was not seen in healthy volunteers or in 10 patients with congestive cardiomyopathy. Our data indicate that reverse doming is a helpful parameter for the diagnosis of aortic regurgitation.

Adolescent↗