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Biomedical subjects

V Hombach

Publications and source records attributed to V Hombach.

At least 55 records · Page 3Linked to original sources
PubMed1999

Aortic regurgitant flow by color Doppler measurement of the local velocity 7 mm above the leak orifice--Part 1: in vitro measurements.

AIMS: The flow convergence method enables the determination of flow across restrictive orifices. It was validated for planar orifice plates and atrioventricular valves. However, its quantitative application to aortic regurgitation is complicated due to the complex valve anatomy which distorts the converging flow field. An open angle formed by the leaflets causes relatively lower velocities in the region near the orifice, resulting in underestimation of flow. Confinement of the flow convergence region by the ascending aorta relatively increases the velocities at greater distance to the orifice and can cause overestimation of flow. We hypothesized that there is a region at intermediate distance to the orifice, where both these effects on the flow field are minimal, so that the local velocity there is only a function of flow. METHODS AND RESULTS: In a flow model, aortic regurgitation was simulated. The flow convergence was imaged by color Doppler. Different scanning directions were used (analogue to apical and parasternal approach). Velocity profiles across the flow convergence were read along the line from the scanhead to the orifice. At a distance of 7 mm to the orifice, a uniform value was found for the ratio of local velocity v(7 mm)/flow (=0.28 cm(-2)). Variations in size (3.5 to 7 mm), site (central versus lateral) and leaflet angle (planar versus inverted funnel) of the orifice and in the scanning approach had only a minimal effect on this value. CONCLUSION: The aortic regurgitant flow convergence is characterized by a relatively uniform V (7 mm)/Q. Independent of variations in the anatomy and the scanning approach, this value directly reflects flow.

Aortic Valve↗
PubMed1999

Aortic regurgitant flow by color Doppler measurement of the local velocity 7 mm above the leak orifice--Part 2: Comparison with cardiac catheterization.

AIMS: An in vitro study of the flow convergence region in aortic regurgitation has shown that regurgitant flow rate can be derived from the local velocity V(7 mm) at 7 mm distance above the leak orifice. This clinical study was performed to test this method in patients. METHODS AND RESULTS: In 67 patients with aortic regurgitation, the flow convergence region was imaged by color Doppler. By analogy with the afore mentioned in vitro study, velocity profiles of the acceleration across the flow convergence region were read from the color maps. The profiles were fitted by using a multiplicative regression model. The V(7 mm) was read from the regression curve, and instantaneous regurgitant flow Q was derived from the V(7 mm) with the equation developed in vitro (Q = V(7 mm).cm2/0.28). Q showed a close association with the angiographic grade. Q-derived regurgitant stroke volume correlated significantly with invasive measurements by the angio-Fick method (r = 0.897, SEE = 19.9 ml, y = 0.88x + 5.9 ml). CONCLUSIONS: Within the color Doppler flow convergence region of aortic regurgitation, the local velocity at 7 mm distance to the leak reflects regurgitant flow rate.

Adult↗
PubMed1999

A human arterial organ culture model of postangioplasty restenosis: results up to 56 days after ballooning.

BACKGROUND: Restenosis is a reparative process that is activated in response to injury induced by angioplasty. Despite numerous experimental models of restenosis the number of human arterial organ culture systems is very limited and long-term experiences do not exist. METHODS AND RESULTS: During routine nephrectomies parts of the renal arteries of 88 patients were extracted, 47 were suitable for organ culture preparations. Sections were made at 3 mm intervals perpendicular to the vessel wall axis. The arterial segments were treated with 3 mm standard balloon-catheters (Medtronic 14K2030E) for 60 s with 3, 6, 9, and 12 bar. After angioplasty, the organ segments were cultured in a mixture of Waymouth's MB 752/1 and Ham F-12, supplemented with 15% fetal calf serum. After 0, 4, 14, 21, 28, and 56 days the organ cultures were fixed in 4% para-formaldehyde and embedded in paraffin. After staining with a modified elastica-van Gieson technique the intimal wall thickening was analyzed with a computerized morphometric system. For the identification of smooth muscle cells (SMC) a monoclonal antibody against smooth muscle alpha-actin was used. Endothelial cells were identified using an anti-human von Willebrand factor. To determine the number of cells undergoing DNA synthesis, bromodeoxyuridine (BrdU), a thymidine analogue, was added to the culture media 18 h prior to fixation. BrdU was detected with a monoclonal antibody, as secondary antibody a biotinylated horse-anti-mouse antibody was used. After 14, 21, and 28 days in culture BrdU-positive cells were detected in the neointima of the organ cultures, indicating mitotic activity in this area. After 28 and 56 days in culture a clear increase of neointimal thickening was found in the morphometric analysis. By positive reaction with antibodies against smooth muscle alpha-actin these cells were partly identified as SMC. CONCLUSIONS: The organ culture model offers opportunities for in vitro investigations of postangioplasty restenosis. The data emphasize the importance of a relatively late proliferative response of SMC in the human arterial organ culture model.

Adult↗
PubMed1999

A randomized trial of elective stenting after balloon recanalization of chronic total occlusions.

OBJECTIVES: The aim of this study was to assess the role of Wiktor stent implantation after recanalization of chronic total coronary occlusions with regard to the clinical and angiographic outcome after six months. BACKGROUND: Beside the common use of stents in clinical practice, the number of stent indications proven by randomized trials is still limited. METHODS: Eighty-five patients with a thrombolysis in myocardial infarction grade 0 chronic coronary occlusion were examined. After standard balloon angioplasty, the patients were randomly assigned to stent implantation, or percutaneous transluminal coronary angioplasty (PTCA) alone (no further intervention). Quantitative coronary angiography was performed at baseline and after six months. RESULTS: The minimal lumen diameter did not differ immediately after recanalization (stent group 1.61 +/- 0.30 mm vs. PTCA group 1.65 +/- 0.36 mm), and increased after stent implantation to 2.51 +/- 0.41 mm. After six months, the stent group still had a significantly greater lumen (1.57 +/- 0.59 vs. 1.06 +/- 0.90 mm; p < 0.01) and a significantly lower restenosis and reocclusion rate (32% and 3%) compared with the PTCA group (64% and 24%); restenosis analysis according to treatment was 72% (PTCA) versus 29% (stent, p < 0.01). Late loss was equal in both groups. At follow-up, the stent patients had a better angina class (p < 0.01), and fewer cardiac events (p < 0.03). A meta-analysis including this trial and three other controlled trials with the Palmaz-Schatz stent showed concordant results. CONCLUSIONS: Stent implantation after reopening of a chronic total occlusion provides a better angiographic result, corresponding to a better clinical outcome with fewer recurrence of symptoms and reinterventions after six months.

Adult↗
PubMed1998

Quantification of mitral and tricuspid regurgitation by the proximal flow convergence method using two-dimensional colour Doppler and colour Doppler M-mode: influence of the mechanism of regurgitation.

In patients with mitral (n=77: organic=49, functional=28) and tricuspid regurgitation (n=55: functional=54) quantified by angiography, the temporal variation of the proximal flow convergence region throughout systole was assessed by colour Doppler M-Mode, and peak and mean radius of the proximal isovelocity surface area for 28 cm/s blood flow velocity were measured. Additionally, the peak radius derived from two-dimensional colour Doppler was obtained. About 50% of the patients with mitral and tricuspid regurgitation showed a typical temporal variation of the flow convergence region related to the mechanism of regurgitation. The different proximal isovelocity surface area radii were similarly correlated to the angiographic grade in mitral and tricuspid regurgitation (rank correlation coefficients 0.55-0.89) and they differentiated mild to moderate (grade < or =II) from severe (grade > or =III) mitral and tricuspid regurgitation with comparable accuracy (82-96%). However, moderate mitral regurgitation due to leaflet prolapse in two patients was correctly classified by the mean M-mode radius and overestimated by both peak radii. Only half of the patients showed a typical variation of the flow convergence region related to the mechanism of regurgitation. The different proximal isovelocity surface area radii were suitable to quantify mitral and tricuspid regurgitation in most patients. However, in mitral regurgitation due to leaflet prolapse the use of the mean M-mode radius may avoid overestimation.

Adult↗
PubMed1998

Heart-rate variability for discrimination of different types of neuropathy in patients with insulin-dependent diabetes mellitus.

It has been shown that patients with insulin-dependent diabetes mellitus (IDDM) may reveal abnormal alterations in heart-rate variability (HRV) due to autonomic neuropathy. This study was performed to prove whether heart-rate variability can be used to stratify diabetic patients with different types of neuropathy. 48 patients with IDDM (age 17-64 yr) underwent standard function tests to assess autonomic and peripheral neuropathy. According to the results of these tests they were divided into 4 groups: Group 1: 18 patients without autonomic or peripheral neuropathy. Group 2: 13 patients with peripheral neuropathy. Group 3: 7 patients with autonomic neuropathy. Group 4: 9 patients with autonomic and peripheral neuropathy. HRV was measured by continuous 24-hours monitoring and time domain parameters were calculated. The results were compared with sex and age-matched healthy controls according to the individual characteristics of the groups and among each subgroup. Our results showed that in Group 1 there was a significant difference of time domain parameters indicative of parasympathetic influence, i.e. rMSSD and pNN50 in comparison to the control subjects (p = 0.002, p = 0.008). These results depended on the duration of diabetes; a subgroup of patients with a duration of IDDM of less than 2 years had no significant differences of HRV values. Group 2 showed the same significant differences. Group 3 and 4 showed significant differences in all measured time domain variables (SDNN, SDANN, SDNN index, rMSSD and pNN50) in comparison to the control subjects (p < 0.04). A comparison of group 1 with group 2 offered significant differences in rMSSD and pNN50 (p = 0.004, p = 0.003). Comparing group 1 with group 3 and 4, all HRV parameters showed significant differences (p < 0.03). In conclusion, HRV is able to distinguish between patients with different types of neuropathy depending on the involvement of parasympathetic or more sympathetic influenced parameters. Furthermore, this method is able to unmask early manifestations of neurological disorders prior to their detection by neurological function tests.

Adolescent↗
PubMed1998

A remark on the high-conductance calcium-activated potassium channel in human endothelial cells.

The patch-clamp technique was used to examine the presence of large conductance calcium-activated potassium channels (BKCa) in human endothelial cells and to characterize their properties in terms of voltage dependence, ion conduction and blockade by iberiotoxin (IbTX). Experiments were performed using cell-attached and outside-out configurations on human umbilical vein endothelial cells (HUVEC). For the experiments HUVECs, which were passaged 6-19 times, were used. In early passages channel activities were absent suggesting the appearance of BKCa depending on cell culture time. The inverse logarithmic voltage sensitivity was 10.17 mV (median) for cell-attached recordings and 12.10 mV (median) for outside-out patches (membrane voltage range: 60-120 mV, symmetrical 140 mM K+ solutions). The I/V relationship was quasilinear in the range of 0-80 mV and exhibited a nonlinear behaviour under further depolarization suggesting some kind of saturation mechanism. Using a sigmoid function to fit the data, channel conductance was calculated as 172.9 pS (median) for cell-attached patches and as 262.1 pS (median) for outside-out patches. IbTX, known as one of the most selective blockers of BKCa was perfused to outside-out patches. In two out of three experiments there was complete block of the ion channel after 1 min.

Cells, Cultured↗
PubMed1998

Time-dependent changes of heart rate variability after percutaneous transluminal angioplasty.

OBJECTIVES: It is not known whether the improvement of myocardial perfusion by percutaneous transluminal coronary angioplasty (PTCA) is followed by a response of the autonomic nervous system depending on the recovery of the myocardium. In this study we investigated changes of heart rate variability parameters in patients before and after PTCA at different time intervals. METHODS: In 42 patients with coronary artery disease documented on angiography, before and after PTCA 24-hour measurements of heart rate variability (HRV) were performed from Holter tapes. The time elapsed between the two measurements was 3 to 4 days in 26 patients and 6 to 8 months in 16 patients. Time domain parameters of HRV were calculated. RESULTS: Comparison of the two recordings showed that the parameters rMSSD, pNN50, and SDNN index decreased, whereas SDNN and SDANN increased. These changes were not statistically significant. A subgroup analysis revealed different results for patients with and without previous myocardial infarction: the parasympathetically and more sympathetically influenced parameters revealed different changes in these groups. Other variables such as ejection fraction or severity of coronary artery disease did not influence the HRV results. Although no statistically significant difference was seen on comparison of the patients with different recording intervals, patients with a longer interval between the two measurement periods showed higher values of all HRV parameters closer to normalized values. This observation may be explained by a delayed recovery of myocardial function after successful revascularization by PTCA.

Adult↗
PubMed1998

Modulation of Ca2+-activated K+ channels in human vascular cells by insulin and basic fibroblast growth factor.

Insulin and basic fibroblast growth factor (bFGF) play an important role in the pathogenesis of atherosclerosis and have been shown to have vasodilatory effects. Since modulation of vascular ion channels determines membrane potential and thereby influences essential Ca2+-dependent intracellular pathways, we have investigated the effect of insulin and bFGF on Ca2+-activated K+ channels (BKCa) in human umbilical vein endothelial cells (HUVEC) and smooth muscle cells. The latter were obtained from either atherosclerotic plaques (SMCP) or from media segments (SMCM) of human coronary arteries. Using the patch-clamp technique, insulin (100 microU/ml) caused a significant increase in BKCa open-state probability in SMCP and HUVEC, whereas no significant changes were observed in SMCM. Basic FGF (30 ng/ml) revealed a significant increase in BKCa activity in HUVEC and a significant decrease in the BKCa open-state probability in SMCP, but caused no changes in SMCM. Thus, growth factors modulate vascular BKCa in a cell-type specific manner, which may be of importance concerning vasoactive and atherogenic effects of growth factors.

Arteriosclerosis↗
PubMed1998

Comparison of the proximal flow convergence method and the jet area method for the assessment of the severity of tricuspid regurgitation.

AIMS: To compare the value of the proximal flow convergence method and the jet area method for the determination of the severity of tricuspid regurgitation. METHODS AND RESULTS: The proximal isovelocity surface area radius and the jet area/length were measured in 71 consecutive patients with angiographically graded (grade 0/I-III) tricuspid regurgitation. Rank correlation coefficients with the angiographic grade were 0.71 (P < 0.001) for the proximal isovelocity surface area radius (aliasing border of 28 cm.s-1), 0.66 (P < 0.001) for the jet area, and 0.63 (P < 0.001) for the jet length. The proximal isovelocity surface area radius was significantly correlated with the jet area/length (correlation coefficients 0.82/0.77, P < 0.001). Correct differentiation between mild to moderate (grade I-II) and severe (grade III) tricuspid regurgitation was achieved in 62 of 71 patients (87%) by means of the proximal isovelocity surface area radius, in 61 of 71 (86%) by the jet area, and in 62 of 71 (87%) by the jet length. Grade III tricuspid regurgitation was not identified in five of 21 patients (24%) by means of the proximal isovelocity surface area radius, in six of 21 (29%) by the jet area, and in seven of 21 (33%) by the jet length. CONCLUSION: The flow convergence method and the jet area method are of similar value for the determination of the severity of tricuspid regurgitation. Both methods differentiated mild to moderate from severe tricuspid regurgitation in most patients. However, underestimation of severe tricuspid regurgitation in 20-30% of the cases represents a serious limitation of both methods.

Adult↗
PubMed1998

Effect of diltiazem and verapamil on endothelin release by cultured human coronary smooth-muscle cells and endothelial cells.

Recent data suggest that endothelin (ET) production is enhanced in coronary atherosclerotic lesions. In several studies, an anti-atherosclerotic effect has been attributed to calcium-channel antagonists. This study aimed to investigate whether ET release from cultured human coronary artery smooth muscle and endothelial cells is influenced by the calcium-channel antagonists diltiazem and verapamil. Coronary plaque smooth-muscle cells (SMCs) were isolated from primary stenosis plaque material. Normal coronary smooth muscle and endothelial cells were obtained from organ donors. Addition of diltiazem (5, 15, 25, 50, or 100 micrograms/ml) and verapamil (0.25, 2.5, 25, 50, or 75 micrograms/ml) to the culture medium induced in all three cell types a dose-dependent reduction in ET secretion (coronary plaque SMCs: diltiazem 98.1 +/- 1.5, 94.9 +/- 5.0, 82.0 +/- 6.4**, 63.3 +/- 3.7***, 38.9 +/- 2.4***; control 108.4 +/- 2.8; verapamil 97.0 +/- 7.7, 91.9 +/- 5.5, 67.3 +/- 4.5**, 30.6 +/- 3.0***, 27.6 +/- 2.2***; control 103.4 +/- 6.1 pg/10(4) cells, n = 6; normal coronary SMCs: diltiazem 9.6 +/- 0.7, 8.7 +/- 0.6, 5.4 +/- 0.5***; 3.7 +/- 0.5***, 3.2 +/- 0.4***; control 10.7 +/- 0.5; verapamil 10.3 +/- 0.9, 10.0 +/- 0.7, 6.6 +/- 0.5***, 4.0 +/- 0.3***, 3.0 +/- 0.3***; control 11.1 +/- 0.6 pg/10(4) cells, n = 6; means +/- SEM, **p < 0.01, ***p < 0.001 vs. control). These data suggest that ET release from cultured coronary smooth muscle and endothelial cells is decreased by diltiazem and verapamil. In further studies, it remains to be elucidated whether the local application of diltiazem or verapamil might have a beneficial effect on the progression of coronary atherosclerosis.

Aged↗
PubMed1998

Expression of intercellular adhesion molecule-1 in human coronary endothelial and smooth muscle cells after stimulation with tumor necrosis factor-alpha.

BACKGROUND: The intercellular adhesion molecule-1 (ICAM-1) is one of several human cell adhesion molecules that play a critical role in the early stages of postangioplasty restenosis. In this study, the in-vitro expression of ICAM-1 in human coronary endothelial cells and human coronary smooth muscle cells (SMC) after stimulation with tumor necrosis factor-alpha (TNF-alpha) was investigated. METHODS AND RESULTS: SMC were isolated from the media of normal human coronary arteries (n = 26) up to 10 h post mortem (HCMSMC) and from human atherosclerotic coronary arteries (HCPSMC) that were extracted by thrombendarterectomy (n = 25). Endothelial cells of human coronary arteries (HCAEC) were purchased from Clonetics (Cell System, Remagen, Germany), and endothelial cells from human umbilical cord veins (HUVEC) were isolated after vaginal delivery. For investigations of the effect of TNF-alpha (2.5, 5, 10, and 20 ng/ml) on the proliferative activity of HUVEC, HCAEC, HCPSMC, and HCMSMC, serum-free media was used. After 24 h cell number and cell size distribution were measured in a cell analyzer system. The proliferation of HCPSMC and HCMSMC was increased by TNF-alpha; however, significant differences compared with controls were not reached. The proliferation of HUVEC and HCAEC was significantly reduced by TNF-alpha. For investigations of the effect of TNF-alpha (2.5, 5, 10, and 20 ng/ml) on the surface expression of ICAM-1, monoclonal anti-ICAM-1 antibodies (84H10) were used. The expression of ICAM-1 was analyzed using an immunofluorescence microscope. For flow cytometry analysis, 5 x 10(3) cells (100% gated) were analyzed using a fluorescence-activated cell sorter. In control cultures with no stimulation, the expression of ICAM-1 was positive in HCAEC, HCPSMC, HCMSMC, and HUVEC. TNF-alpha stimulated the expression of ICAM-1 in a time- and dose-dependent manner. After maximal stimulation with TNF-alpha (20 ng/ml for 24 h), the expression of ICAM-1 was stronger in HCMSMC than in HCPSMC. CONCLUSIONS: These results suggest that the cytokine TNF-alpha regulates the expression of ICAM-1 in both human coronary endothelial cells and SMC, and could therefore play an important role in the pathophysiology of inflammatory and immune processes in restenosis after angioplasty.

Cell Division↗
PubMed1998

C-reactive protein frequently colocalizes with the terminal complement complex in the intima of early atherosclerotic lesions of human coronary arteries.

There is increasing evidence that complement activation may play a role in atherogenesis. Complement proteins have been demonstrated to be present in early atherosclerotic lesions of animals and humans, and cholesterol-induced atherosclerotic lesion formation is reduced in complement-deficient animals. Potential complement activators in atherosclerotic lesions are now a subject matter of debate. C-reactive protein (CRP) is an acute-phase protein that is involved in inflammatory processes in numerous ways. It binds to lipoproteins and activates the complement system via the classic pathway. In this study we have investigated early atherosclerotic lesions of human coronary arteries by means of immunohistochemical staining. We demonstrate here that CRP deposits in the arterial wall in early atherosclerotic lesions with 2 predominant manifestations. First, there is a diffuse rather than a focal deposition in the deep fibroelastic layer and in the fibromuscular layer of the intima adjacent to the media. In this location, CRP frequently colocalizes with the terminal complement complex. Second, the majority of foam cells below the endothelium show positive staining for CRP. In this location, no colocalization with the terminal complement proteins can be observed. Our data suggest that CRP may promote atherosclerotic lesion formation by activating the complement system and being involved in foam cell formation.

Animals↗
PubMed1998

Direct enzyme immunometric measurement of plasma big endothelin-I concentrations and correlation with indicators of left ventricular function.

Recent studies have suggested that the plasma concentrations of endothelin-1, a potent vasoconstrictive peptide, are increased in patients with congestive heart failure. This study aimed to evaluate a new direct ELISA for big endothelin-1 (the precursor of endothelin-1), in comparison with a big endothelin-1 ELISA using plasma sample extraction, and to investigate whether plasma big endothelin-1 concentrations correlate with indicators of left ventricular function. The direct ELISA yielded significantly (P < 0.001) lower results than the assay with extracted samples (0.9 +/- 0.5 pmol/L vs 2.7 +/- 1.9 pmol/L; n = 90); however, the results of the two assays were closely correlated (r = 0.86, P < 0.001). Plasma big endothelin-1 concentrations exhibited a significant (P < 0.001) negative correlation (r = -0.46, r = -0.40) with the left ventricular ejection fraction and a significant positive correlation (r = 0.40, P < 0.001; r = 0.36, P < 0.01) with the left ventricular end-diastolic pressure and the left ventricular end-diastolic (r = 0.42, r = 0.38, P < 0.001) and end-systolic (r = 0.52, r = 0.47, P < 0.001) volume indices. Plasma big endothelin-1 concentrations were notably greater in patients with New York Heart Association (NYHA) class II-IV symptoms than in patients without cardiac disease or in patients categorized to NYHA class I. These data suggest that plasma big endothelin-1 concentrations, measured by a direct ELISA, correlate with hemodynamic indicators and symptoms of left ventricular dysfunction.

Adult↗
PubMed1998

[Clinical and economic cost-benefit relations in treatment of patients with coronary heart disease].

Economic evaluation of medical treatment in terms of costs and utility has gained increasing interest within the medical community and in political discussions. In particular this applies for highly prevalent diseases such as coronary artery disease, still the most common cause of death in the western world. Health economy studies can be performed from different perspectives (e.g., hospital, insurance company, society) and with various approaches (e.g., cost-utility analysis, cost minimization). Those will be discussed for the primary prevention of myocardial infarction, coronary stent implantation, and for rehabilitation programs after myocardial infarction, serving as examples. Health-economical analyses provide data to compare treatment strategies beyond a certain speciality. However, economic evaluation is only one step within the medical assessment process and does not per se imply the political allocation of financial resources.

Angioplasty, Balloon, Coronary↗
PubMed1997

Influence of physical activity on 24-hour measurements of heart rate variability in patients with coronary artery disease.

This study assessed the influence of physical activity on time domain variables of heart rate variability (HRV) during 24-hour electrocardiographic registrations. Changes in time domain variables of HRV (in particular SDNN) obtained from Holter recordings were proven as strong predictors of cardiac events in patients with coronary artery disease. Although 24-hour measurements of HRV recordings are a standard technique, little is known about the effects of the environment during the registration period. This applies especially to the type and nature of physical activity. In a prospective study, 106 patients with angiographically proven coronary artery disease were randomized into 2 groups. Group 1 consisted of 54 patients with recordings under normal daily physical activities. Group 2 consisted of 52 patients who were immobilized during the recording. Both groups were comparable concerning clinical parameters. The results of 24-hour measurements of HRV with analysis of time domain variables (SDNN, SDANN, SDNN index, rMSSD, and pNN50) were compared among the 2 patients groups, and with a healthy control group. Comparison of immobilized patients with healthy controls showed statistically significant differences of all HRV parameters (p <0.01). However, when comparing the activity group with healthy controls, none of the parameters showed any significant differences. Comparison of the subgroups revealed statistically significant differences of the parameters SDNN, SDANN (p <0.01), and borderline results for rMSSD and pNN50 (p = 0.05). Our results indicate that time domain variables of HRV calculated from 24-hour recordings are significantly influenced by the level of physical activity and the upright posture during registration. This methodologic aspect has to be considered, especially if HRV measurements are used as prognostic markers in patients with coronary heart disease.

Adult↗
PubMed1997

Signal-averaged electrocardiogram in patients with insulin-dependent (type 1) diabetes mellitus with and without diabetic neuropathy.

The purpose of this study was to investigate the presence of ventricular late potentials derived from signal-averaged ECG in patients with IDDM with and without diabetic neuropathy. Eighty patients with IDDM but without evidence of cardiac disease and 80 age-matched healthy control subjects were investigated. The corrected QT interval was measured from the standard surface electrocardiogram. Ventricular late potentials were derived from signal-averaged electrocardiogram. Out of the 80 diabetic patients, 20 had an autonomic neuropathy, 20 had an isolated peripheral neuropathy, and 40 had no symptoms of neuropathy. The corrected QT interval was significantly prolonged in patients with an autonomic neuropathy as compared with the control group (436 +/- 23 ms(x 5) vs 384 +/- 23 ms(x 5), p < 0.001). In the other patient groups there was no significant prolongation of the corrected QT interval. Ventricular late potentials were present in 3 diabetic patients with an isolated peripheral neuropathy and in 1 control subject (NS). No diabetic patient with an autonomic neuropathy had ventricular late potentials. Our data did not indicate an increased incidence of ventricular late potentials derived from signal-averaged electrocardiogram in diabetic patients independent of a coexisting diabetic neuropathy or a prolonged corrected QT interval.

Adolescent↗