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H Völler

Publications and source records attributed to H Völler.

At least 37 records · Page 2Linked to original sources
PubMed1999

[Left ventricular remodeling: pathophysiological mechanisms and therapeutic recommendations].

Hospital mortality from acute myocardial infarction has decreased in the last two decades. Left ventricular dysfunction therefore have been mainly due to ischemia. After extensive myocardial infarction, there are processes of adaptation (remodeling) which result in altered geometry of the left ventricle. The effects of this on neurohormonal systems (organ regulation), on the changed ratio of myocyte mass and collagen content owing to reactive and reparative fibrosis (organ texture) and on the molecular and cellular mechanisms (organ structure) are of crucial importance. Depending on the structural changes, the myocardial contractility decreases. This is associated with an activation of the circulating renin-angiotensin-aldosterone system (RAAS). The fundamental knowledge available has led to the therapeutic use of ACE inhibitors in the post-infarct period. This treatment enabled a sustained reduction of mortality in several large-scale randomized studies. The effect of early administration in patients with clinical signs of heart failure and/or left ventricular dysfunction was very much greater compared to unselected controls. Only 17 and 13 patients had to be treated after selection in order to save one life in the AIRE and TREACE Study respectively (NNT: number needed to treat), whereas e.g. in the ISIS-4 study 200 unselected patients had to be treated. In clinical practice, however, this life-saving therapy is only used in every second patient requiring treatment. With consideration of an individual form of treatment (anterior infarction, large infarct area, reinfarction, clinical signs of heart failure as well as arterial hypertension and diabetes mellitus), a greater acceptance of evidence-based guidelines is thus desirable. Treatment with a high dose may be expected to be of additional benefit.

Angiotensin-Converting Enzyme Inhibitors↗
PubMed1998

[Effect of cardiac embolism sources on origin of territorial cerebral infarcts].

BACKGROUND AND PURPOSE: To test the association of cardiac sources of embolism with territorial type brain infarcts. METHODS: From a prospective cerebral ischemia data base the 106 consecutive patients with territorial type cerebral infarcts on computerized tomography were analyzed. The 85 consecutive patients with lacunar lesions served as a comparison group. The association of cardiac sources of embolism with territorial types infarcts was assessed using univariate Chi Square tests and logistic regression models. Cardiac sources of embolism were defined as:atrial fibrillation, left cardiac thrombi, valvular vegetations, wall motion and valvular abnormalities, left atrial enlargement, open foramen ovale, septal aneurysm, mitral valve prolaps, and aortic arch atherothrombosis (all findings--except for atrial fibrillation--assessed by echocardiography). RESULTS: Atrial fibrillation was significantly associated with territorial type infarcts (odds ratio 2.2, 95% confidence interval 1.01-4.8). This effect was independent of additional cardiac diseases, other cardiac abnormalities, carotid artery stenosis, and patient age. Most likely due to the small sample size, left cardiac thrombi only showed a non-significant trend towards an association with territorial infarcts (odds ratio 3.0, 95% confidence interval 0.7-12.3). The rate of all other cardiac findings did not differ significantly between the comparison groups. CONCLUSION: Atrial fibrillation and cardiac thrombi showed an association with territorial type infarcts. Other so-called cardiac sources of embolism--except for mechanical valves and bacterial endocarditis which were not represented in our sample--revealed no clinically relevant association with embolic brain infarct pattern.

Adult↗
PubMed1997

Comparison of the prognostic value of dipyridamole and dobutamine stress echocardiography in patients with known or suspected coronary artery disease.

Direct comparison of the utility of dipyridamole stress echocardiography and dobutamine stress echocardiography was performed to identify patients at risk of future cardiac events in 134 patients with suspected or known coronary artery disease. The predictive values of dobutamine and dipyridamole were remarkably similar.

Adrenergic beta-Agonists↗
PubMed1997

[Measuring stress hemodynamics in pulmonary circulation during the inpatient phase after myocardial infarct: a rightfully "forgotten" evaluation?].

UNLABELLED: In 123 consecutive patients pulmonary hemodynamics at rest and during exercise were measured 7-10 days after acute myocardial infarction and systemic thrombolysis. Right- and left-heart catheterizations were performed at the same session and repeated after 6 months. We investigated if right-heart catheterization could predict the number of stenotic or occluded coronaries, the angiographic ventricular function and/or, most important, if the patient would profit from revascularization by PTCA or coronary surgery. RESULTS: 1) Pulmonary hemodynamics at rest and during exercise did not correlate to the number of stenotic or occluded coronaries, but exercise tolerance did. 2) Correlation between ventricular function and pulmonary hemodynamics was weak. 3) Only patients with pathologically elevated pulmonary pressures at exercise showed profit from revascularization (increase of ejection fraction > 5% at control). This profit was closely correlated to the angiographic extent of ventricular damage. Consequences from our results: Individual exercise tolerance can easily be measured non-invasively. Ventricular function can be measured non-invasively as well by echocardiography. Measurement of pulmonary hemodynamics at rest and during exercise does not contribute to planning the future management of the postinfarction patient and does not replace coronarography when indicated by clinical or non-invasive parameters.

Adult↗
PubMed1997

Factors influencing the diagnostic accuracy of dobutamine stress echocardiography.

BACKGROUND: While Dobutamine stress echocardiography is a well established tool, the range of the diagnostic accuracy found in the literature is rather large. The main reason for this is the fact, that different test protocols were used. Aim of this study was to assess the effects of both addition of atropine as well as consideration of a hyperdynamic response while interpreting the stress echocardiogram on the diagnostic accuracy. METHODS AND RESULTS: 120 consecutive patients were examined and divided into the following groups: A) achieving their age predicted heart rate with dobutamine, B) termination of the test due to ischemia, C1) negative test without reaching the predicted heart rate, and C2) C1 following addition of atropine. All of the echocardiograms were analyzed twice: 1) regarding the lack of a hyperdynamic response to dobutamine as ischemia (Hyper analysis), and 2) ignoring the hypercontractility (Conventional analysis). The accuracy of A and B were 88% and 90% resp. Group C1 had a very poor accuracy of 60%. This rose significantly (p < 0.01) after atropine (C2 = 84%), without leading to an increase of adverse effects. Conventional wallmotion analysis lead to an overall accuracy of 87% (groups A, B, and C2), while Hyper analysis showed an accuracy of 90% (p < 0.01). CONCLUSIONS: To achieve a high accuracy Dobutamine stress echocardiography should always be combined with atropine to reach a target heart rate. The wallmotion analysis should be based on the assumption that a hyperdynamic response to dobutamine is normal, while its lack is indicative of ischemia.

Adult↗
PubMed1996

Comparison of the diagnostic potential of four echocardiographic stress tests shortly after acute myocardial infarction: submaximal exercise, transesophageal atrial pacing, dipyridamole, and dobutamine-atropine.

This study assessed and compared the diagnostic potential of submaximal exercise, transesophageal atrial pacing, dipyridamole, and dobutamine-atropine stress echocardiography tests shortly after acute myocardial infarction. In 121 study patients, 325 digital echocardiographic stress tests were attempted 10 to 11 days after acute myocardial infarction: 83 submaximal exercise tests, 121 high-dose dipyridamole echocardiography tests (DET), 69 transesophageal atrial pacing tests (< 150 beats/min), and 52 dobutamine tests, starting at 10 microgram/kg per minute, increasing stepwise to 40 microgram kg/min, and coadministering atropine in 12 patients (dobutamine-atropine stress echocardiography [DASE]). Results were correlated to a coronary artery diameter stenosis > or = 50% as determined by quantitative angiography. Feasibility to perform submaximal exercise echocardiography, atrial pacing echocardiography, DET, and DASE was 89%, 52%, 98%, and 88%, respectively. Atrial pacing was not tolerated by 18 patients and refused by 6 (9%). Severe but not life-threatening side effects were hypotension in DET (2%) and tachyarrhythmias in DASE (6%). Test positivity in multivessel disease with submaximal exercise, DET, and DASE was 55%, 93%, and 90%, respectively, and in 1-vessel disease 47%, 65%, 71%, and for atrial pacing, 82%, respectively. We conclude that submaximal exercise has limited sensitivity and atrial pacing limited feasibility. The pharmacologic stressors provide a useful, safe diagnostic approach: DET with slightly lower sensitivity in 1-vessel disease and DASE with insignificantly less feasibility.

Atropine↗
PubMed1996

Circadian, day-of-week, and seasonal variability in myocardial infarction: comparison between working and retired patients.

The circadian, day-of-week, and seasonal distributions of acute myocardial infarction and its association with the patients' working status were analyzed in a regionally defined population (n = 103, 322) monitored from 1980 to 1988. Included were 2906 consecutive patients (1746 [60.1%] men and 1160 [39.9%] women; mean age 67.8 years) with confirmed diagnosis (by standardized diagnostic criteria in hospitalized patients and autopsy results in out-of-hospital deaths). The time of myocardial infarction on the basis of onset of symptoms was known in 1901 cases. Myocardial infarction occurred more frequently (p < 0.05) during the morning from 7:00 to 10:00 AM, on Mondays, and during the winter from January to March compared with other times of day, days of the week, and seasons. Compared with retired patients, working patients (32%) had a second circadian peak, in the afternoon at 4:00 PM (p < 0.05), and a trend toward an additional seasonal peak in September (p value not significant), whereas the day-of-week pattern was similar in the two subgroups. The occurrence of myocardial infarction demonstrates marked circadian, day-of-week, and seasonal variations, with some differences between working and retired patients. Further investigation of possible triggering events may aid in identifying underlaying mechanisms and perhaps in improving prevention of the disease.

Aged↗
PubMed1996

[Diagnostic advantage by transthoracic and transesophageal echocardiography in acute ischemic infarct. A contribution to indications for transesophageal echocardiography].

The yield of TTE and TEE in identifying cardiac sources of embolism in patients with TIA or stroke was calculated from data from the Berlin Stroke Data Bank. High risk sources of embolism were detected by TTE in 4.2% with and in 1.6% of patients without evidence of cardiac disease from case history, clinical symptomatology, and ECG respectively. TEE yielded high risk sources of embolism in 10.6% of patients with and in 4.2% of patients without evidence of cardiac disease from case history, clinical symptomatology, ECG, and TTE respectively. Pathological findings were 12 atrial thrombi, 4 ventricular thrombi, and 1 atrial myxoma. 12 out of 14 atrial thrombi were only detected by TEE and not by TTE. There was a significant association of high risk cardiac sources of embolism with pial artery infarct pattern in CCT compared with lacunes. The yield of TEE in detecting high risk sources was not significantly associated with CCT infarct pattern probably due to the small numbers of investigations.

Adult↗
PubMed1996

[Potential embolism sources in transesophageal echocardiography--prognostic value in patients with cerebral ischemia].

To determine whether potential sources of embolism such as atrial septal aneurysm (ASA), patent foramen ovale (PFO), mitral valve prolapse and atherosclerotic aortic debris can influence the outcome of patients after first cerebral ischemic event (CIE), 214 patients (124 stroke, 21 RIND, 69 TIA) were examined by transesophageal echocardiography (TEE) up to 3 weeks after CIE and followed up for 12 months. For risk estimation, the patients were subdivided into group I = without and group II = with potential sources of embolism. We additionally took into account cardiovascular diseases and atherosclerotic risk factors (group la + IIa without, Ib + IIb with). Recurrence occurred in 14 out of 214 patients (6.5%). Univariate analysis demonstrated that the presence of ASA, PFO and aortic debris as well as cardiovascular diseases and atherosclerotic risk factors was associated with a twofold to threefold higher incidence of recurrent events. While potential sources of embolism alone had no influence on the recurrence rate (group I:8/111 = 7.2% versus group II: 6/103 = 5.8%, n.s.), this was significantly different in relation to cardiovascular diseases and atherosclerotic risk factors (groups Ia + IIa: 0/66 = 0%, groups Ib + IIb: 14/148 = 9.8%, p < 0.01). Our results show that potential sources of embolism do not appear to influence the recurrence rate in cardiac healthy subjects. In patients with cardiovascular diseases, however, potential sources of embolism are associated with a higher risk of recurrence, and should therefore be imaged by TEE.

Adult↗
PubMed1996

[Possible errors in diagnosis of left atrial thrombosis in transesophageal echocardiography].

The detection of thrombi in the left atrium and left atrial appendage by transesophageal echocardiography has significant diagnostic and therapeutic value. However, it requires high method accuracy in routine evaluation. In order to record the percentage of false positive findings, a reevaluation was performed by two experienced examiners using the video recordings of 51 patients, in whom a thrombus has been diagnosed during the routine evaluation. From 1988 to 1994, these thrombi were diagnosed in 726 patients in whom we looked for a source of possible cardiac embolism. In the reevaluation of the 43 cases with sufficient video recordings, in 26 (60%) the diagnosis was classified as false-positive and in 5 patients (12%) as questionable. Thrombus diagnosis was confirmed in only 12 (28%) cases. The incidence of false-positive findings decreased over the course of years with 8.3% (1988-1990), 2.9% (1991-1992) and 0.4% (1993-1994), p = 0.0001. The agreement in the reevaluation between the two examiners was high (interobserver variability 7%), whereby completely divergent evaluations did not occur. Typical diagnostic pitfalls included a prominent trabecular structure in the left atrial appendage (n = 10), the membranous structure between the left atrial appendage and the upper left pulmonary vein (n = 7), transition of the lower left atrium/left atrial appendage (n = 3) and branches within the apex of the left atrial appendage (n = 2). When searching for thrombi in the left atrium and left atrial appendage, there is a high risk of false-positive findings, especially for the unexperienced investigator. Attention must be paid to the typical causes of diagnostic pitfalls in the case of complex and variable anatomy.

Adolescent↗
PubMed1995

Left ventricular hypertrophy and diastolic dysfunction: their relation to coronary heart disease.

Diastolic dysfunction is an early sign in the temporal sequence of ischemic events in coronary heart disease. The ischemic cascade, beginning with an oxygen demand supply imbalance and metabolic alterations, identifies diastolic disorders of the left ventricle (LV) as an early phenomenon, sometimes before systolic dysfunction, electrocardiographic changes, or chest pain occur. Although the physiology of diastolic function is complex, the factors contributing to diastolic disturbances can be differentiated into intrinsic and extrinsic LV abnormalities. Intrinsic mechanisms include (a) impaired LV relaxation, (b) the complex of LV hypertrophy, and (c) increased LV asynchrony. Myocardial hypertrophy leads to an increase of the myocardial mass/volume ratio, and the degree of hypertrophy is the main determinant of chamber stiffness. The main, if not unique, determinant of myocardial diastolic tissue distensibility is the structure and concentration of the collagen. Consequently, tissue stiffness is increased in coronary disease by reparative interstitial fibrosis or scar following myocardial infarction. In myocardial hypertrophy the LV collagen concentration is elevated due to reactive fibrosis. An increase in regional asynchrony of LV contraction and relaxation is a result of regional ischemia as well as of LV hypertrophy and tissue fibrosis. Factors extrinsic to the LV causing diastolic disorders include (a) increased central blood volume, which will increase left ventricular pressure without altering the LV pressure-volume relation, and (b) ventricular interaction mediated by pericardial restraint, which may cause a parallel upward shift of the diastolic LV pressure-volume relation. Improved insight into the mechanisms of LV relaxation and filling characteristics help in the treatment of LV diastolic dysfunction.

Coronary Disease↗
PubMed1994

[Endocardial fibrosis in neuroendocrine tumors of the gastroenteropancreatic system].

Clinical characteristics, echocardiographic and Doppler echocardiographic findings, as well as serum levels of chromogranin A were recorded on 62 patients (27 women, 35 men; mean age 55 [11-83] years) with histologically confirmed tumours of the gastroenteropancreatic (GEP) system. Changes in the right heart were found in 14 patients (22%), club-like thickening of tricuspid leaflets in 13, tricuspid regurgitation in 14, stenosis in 2 and right atrial or right ventricular dilatation in 11 and 5, respectively. There was no difference between the patients with or without right-heart changes in regard to age, presence of carcinoid syndrome, duration of symptoms, primary tumour site, pattern of metastases, treatment or chromogranin A level. Two patients with nonfunctioning tumours had right-heart changes. While clinical and biochemical parameters did not identify patients with right-heart changes, echocardiography demonstrated all haemodynamically significant endocardial changes. Even patients with nonfunctioning GEP tumours should be regularly monitored by echocardiography.

Adolescent↗
PubMed1994

[Early diagnosis of left ventricular dysfunction following acute myocardial infarct. Doppler echocardiography in a study of its course].

The prognosis of acute myocardial infarction depends on the development of left-ventricular dilatation and chronic heart failure. Serial echocardiography was performed on admission and on days 2, 4 and 6, to discover the temporal course of any early myocardial adaptation. There were 78 patients (20 women, 58 men; mean age 59 [49-69] years) with acute myocardial infarction and systemic thrombolysis, first studied up to 4 hours after onset of symptoms. The patients were divided into two groups according to infarct size as measured by creatine kinase ("area under the curve"--AUC); group 1: CK AUC < 12 IU/ml.h; group 2: CK AUC > 12 IU/ml.h. While there was no difference between the two groups on admission and on day 2, filling patterns differed significantly at the end of the first postinfarction week in that maximal early diastolic flow velocity (E) in group 1 was 0.65 m/s, but 0.73 m/s in group 2 (P < 0.05); maximal late diastolic flow velocity (A), group 1: 0.71, group 2: 0.58 m/s (P < 0.01); E/A ratio: 0.89 vs 1.22 (P < 0.001); integrated E/A ratio 1.37 vs 1.77 (P < 0.001), and the atrial component of left-ventricular filling 42 vs 36% (P < 0.001). It is concluded that the serial measurement of left-ventricular filling by Doppler echocardiography in the first post-infarction week can identify patients with impaired left-ventricular function through differences in flow pattern. Drug or interventional treatment can then be started early to prevent further left-ventricular dilatation and in this way improve prognosis.

Aged↗
PubMed1994

Improvement of endocardial border delineation in suboptimal stress-echocardiograms using the new left heart contrast agent SH U 508 A.

Recent studies have shown that the saccharide based echocardiographic contrast agent SH U 508 A opacifies the left ventricle after i.v. injection, thus possibly improving endocardial border definition. This study was performed to determine whether SH U 508 A can enhance the wall motion analysis in suboptimal echocardiographic images at rest and following pharmacological stress. Ten male patients (mean 58 years) exhibiting > or = 30% endocardial border dropout were examined prior to a diagnostic left heart catheterization. Five patients were stressed with Dobutamine, 5 with Dipyridamole. The wall motion was assessed visually (qualitatively) as well as computer-aided (quantitatively). The concordance between left ventricular angiography as 'gold standard' and resting echocardiography regarding the wall motion analysis was significantly improved from 64.5% to 90.3% following the injection of SH U 508 A (p < 0.05). A delineation score (0 = not delineated, 1 = delineated) of 12 individual wall segments was used. The mean delineation score at baseline was 6.1 +/- 1.4 at rest and 6.6 +/- 1.9 during stress. SH U 508 A significantly (p < 0.01) increased the score to 9.6 +/- 1.9 and 10.3 +/- 1.7, respectively. The intraobserver variability for assessing the delineation score was significantly (p < 0.04) improved by SH U 508 A. SH U 508 A, however, did not improve the quantitative assessment of the left ventricular function. Only 40% of the patients could be analyzed following SH U 508 A injection. No severe adverse reactions were seen. SH U 508 A led to a significant, clinically important, improvement in the interpretation of stress echocardiograms in patients with inconclusive routine echocardiograms.

Adult↗
PubMed1994

[Intraoperative transesophageal versus preoperative transthoracic contrast echocardiography. A method for detection of patent foramen ovale in neurosurgical patients].

Preoperative detection of a patent foramen ovale (PFO) may be achieved employing either transthoracic echocardiography (TTE) with the Valsalva manoeuvre in the awake patient or trans-oesophageal echocardiography (TEE) in the anaesthesised patient. Our study was undertaken to validate these methods with regard to their efficacy in identifying patients at risk for paradoxical air embolism (PAE). METHODS. In 67 patients ranging from 28 to 70 years of age, TTE was performed utilising the Valsalva manoeuvre prior to surgery. The patients were informed about all procedures and agreed to take part in the study. After induction of anaesthesia the patients were evaluated with TEE in the supine and sitting positions. At end-inspiration 10 ml agitated gelatine solution (Gelafundin) was injected through a central venous catheter into the right atrium after airway pressure of 20 cm H2O had been maintained for 5 s. The injected bolus was observed throughout the ventilatory cycle, with special attention being given to early expiration and systole. A right-to-left shunt was assumed if five echo targets were observed in the left atrium. RESULTS. The prevalence of PFO detected by TTE/Valsalva was 9%. The diagnosis was confirmed by TEE in 2 patients in the supine and 1 in the sitting position. An echocardiogram in these patients showed bulging of the septum to the left, which was not seen in those patients in whom PFO was detected only by TTE. DISCUSSION. The reason for the lower incidence of PFO detected by TEE during airway pressure 20 cm H2O may have been an insufficient increase of pressure in the right atrium with a negative right-to-left atrial pressure gradient. A standardised ventilation manoeuvre with supra-atmospheric airway pressure of 20 cm H2O is not sufficient. Bulging of the intra-atrial septum from right to left during airway pressure is a possible indication of the efficacy of the manoeuvre, regardless of the influence of the breathing pattern.

Adult↗