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J Gehring

Publications and source records attributed to J Gehring.

At least 19 recordsLinked to original sources
PubMed1997

Evaluation of signal-averaged cardiokymography for the detection of ischaemic left ventricular dysfunction.

UNLABELLED: Cardiokymography (CKG) is a non-invasive method for the detection of patients with coronary artery disease (CAD). Issues of the present study were to evaluate the feasibility, sensitivity and specificity of a recently developed signal-averaged CKG system for detecting patients with pharmacologically induced ischaemic left ventricular wall motion abnormalities (WMA) during pharmacologic stress echocardiography (SE). Precordial CKG curves were recorded in 100 consecutive patients who underwent dobutamine-SE for suspected CAD. For interpretation, CKG curves were classified into three different types, depending on the degree of systolic outward motion. CKG test results were regarded as positive (indicating myocardial ischaemia) if there was a change of the baseline CKG type at peak pharmacologic stress. The CKG test results were positive in 18 of 27 patients with a pathologic dobutamine-SE (sensitivity 67%), but did not show any change of the prior CKG type in 57 of 69 patients with a normal SE (specificity 83%). Patients with a true positive CKG test had significantly (P<0.05) more echocardiographic segments with WMA than patients with a false negative CKG test. CONCLUSIONS: Signal-averaged CKG can detect patients with ischaemic ventricular dysfunction. Sensitivity of CKG in detecting patients with WMA depends on the extent of left ventricular ischaemia. Further studies are needed to define the diagnostic value of signal-averaged CKG in the non-invasive detection of patients with suspected CAD.

Adult↗
PubMed1996

Cardiovascular risk factors, ECG abnormalities and quality of life in subjects with atrial fibrillation.

In Central European regions epidemiologic findings for atrial fibrillation (AF) in a randomly selected population are not available. Therefore, information obtained by a standardized examination procedure including resting 12 lead ECG of 4003 participants (2014 men, 1989 women), aged 25 to 64 years, of the MONICA-Augsburg Survey 1984/85 were analysed. Reexamination of 3753 subjects took place three years later (Follow-up Study 1987/88). Persons with AF in the baseline survey (n = 13) were compared with an age-and sex-matched control group (n = 156) without AF, chosen from the same population sample, with regard to cardiovascular risk factors, associated disease and disturbances in the subjects' general well-being. In 1984/85 thirteen cases with AF (6 males, 7 females) were observed, giving an age-standardized prevalence of AF in males of 0.22% and in females of 0.34%. The age of men with AF ranged between 50 and 63 years and of women between 61 and 64 years. No significant differences were observed in persons with AF compared to the control group in risk factor levels and alcohol consumption; however, significant differences could be seen concerning disturbances in quality of life like self-reported health status (p < 0.001), sleep disturbances (p < 0.05), antihypertensive medication (p < 0.001). AF cases were found to have further ECG abnormalities significantly more often (left anterior hemiblock: p < 0.05; ventricular premature beats: p < 0.05). In all subjects with AF in the initial examination 1984/85 AF was found three years later (chronic AF). Overall 13 new cases (7 men, 6 women) were identified in the 1987/88 follow-up. The prevalence of AF in a South German population is comparable with AF prevalences reported from studies in other populations (e.g.) Framingham 1950, Reykjavik 1967/70). Associated ECG abnormalities were found more frequently in subjects with AF. Cases with AF have considerable disturbances in their general well-being.

Adult↗
PubMed1993

Assessment of global and regional myocardial function using the Minnesota Q/QS codes. A comparison with clinical ECG interpretation.

The authors investigated 244 consecutive patients with suspected coronary artery disease by coronary angiography and quantitative left ventriculography to compare the Minnesota Q/QS code (MC) with clinical electrocardiographic (ECG) interpretation. Patients who were suspected to have wall motion abnormalities for reasons other than coronary artery disease for possible regional wall motion abnormalities were excluded. Out of 244 patients, 159 (65%) had wall motion abnormalities. The sensitivity for detecting wall motion abnormalities was 21% for MC 1.1 and 51% for MC 1.1-3, whereas clinical ECG interpretation showed a sensitivity of 73%. Specificity for MC 1.1 was 93% and for MC 1.1-3 it was 84%. Specificity of clinical ECG interpretation (84%) was comparable. Compared to the MC, clinical ECG interpretation showed a stronger association with left ventricular ejection fraction, number of segments with abnormal wall motion, and severity of wall motion abnormality. Anterior myocardial infarction presented more often with clinical ECG changes (71%) and with a Q/QS code (50%) than inferior myocardial infarction (61% and 41%, respectively). In summary, in contrast to clinical ECG criteria, the MC has high specificity at the expense of a low sensitivity.

Cineradiography↗
PubMed1991

The diagnostic performance of computer programs for the interpretation of electrocardiograms.

BACKGROUND: Computer programs for the interpretation of electrocardiograms (ECGs) are now widely used. However, a systematic assessment of various computer programs for the interpretation of ECGs has not been performed. METHODS: We undertook a large international study to compare the performance of nine electrocardiographic computer programs with that of eight cardiologists in interpreting ECGs in 1220 clinically validated cases of various cardiac disorders. ECGs from the following groups were included in the sample: control patients (n = 382); patients with left ventricular hypertrophy (n = 183), right ventricular hypertrophy (n = 55), or biventricular hypertrophy (n = 53); patients with anterior myocardial infarction (n = 170), inferior myocardial infarction (n = 273), or combined myocardial infarction (n = 73); and patients with combined infarction and hypertrophy (n = 31). The interpretations of the computer programs and the cardiologists were compared with the clinical diagnoses made independently of the ECGs, and the computer interpretations were compared with those of the cardiologists. RESULTS: The percentage of ECGs correctly classified by the computer programs (median, 91.3 percent) was lower than that of the cardiologists (median, 96.0 percent; P less than 0.01). The median sensitivity of the computer programs was also significantly lower than that of the cardiologists in diagnosing left ventricular hypertrophy (56.6 percent vs. 63.9 percent, P less than 0.02), right ventricular hypertrophy (31.8 percent vs. 46.6 percent, P less than 0.01), anterior myocardial infarction (77.1 percent vs. 84.9 percent, P less than 0.001), and inferior myocardial infarction (58.8 percent vs. 71.7 percent, P less than 0.0001). The median total accuracy level (the percentage of correct classifications) was 6.6 percent lower for the computer programs (69.7 percent) than for the cardiologists (76.3 percent; P less than 0.001). However, the performance of the best programs nearly matched that of the most accurate cardiologists. CONCLUSIONS: Our study shows that some but not all computer programs for the interpretation of ECGs perform almost as well as cardiologists in identifying seven major cardiac disorders.

Cardiology↗
PubMed1991

[24-hour blood pressure profile: reproducibility of automatic ambulatory measurement].

Twelve patients (8 males, 4 females; mean age 53 [43-60] years) who were undergoing rehabilitation treatment after myocardial infarction were studied to ascertain the reproducibility of ambulatory automatic blood pressure measurements. All were in the last stage of a rehabilitation programme (tolerance to ordinary activity; symptom-free exercise at 75 W). Within two weeks 2, 3 or 4 blood-pressure profiles over 24 hours (total of 32 readings) were obtained by automatic measurement and the records and mean values were compared. Single mild stresses, such as gymnastic exercise or visit to the doctor, were identifiable on the records, but did not alter the overall profile or mean values. Normotensives, hypertensives and borderline hypertensives had 24-hour profiles which were nearly identical with regard to the curve "envelope", day-night profile and mean values in the individual patients. Mean values of diastolic and systolic pressures day by day in each patient showed no deviations greater than 5 mm Hg. Therapeutic measures were recognizable by parallel fall of the curve "envelope", as well as by a reduction in mean value.--At least in these selected patients a single 24-hour profile would in principle have sufficed to describe blood pressure behaviour.

Adult↗
PubMed1990

Evaluation of ECG interpretation results obtained by computer and cardiologists.

In an international project investigators from 25 institutes are trying to establish a common reference library and evaluation methods for testing the diagnostic performance of various ECG computer programs and of cardiologists, based on ECG-independent clinical information. A first set of 500 validated ECGs was collected and analyzed by fifteen different computer programs and nine cardiologists, seven of who analysed the ECG and five the VCG. A coding scheme was used to map individual diagnostic statements onto a common set. Combined program and referee results were obtained by weighted averaging. Preliminary results indicate that the classification accuracy of several programs can still be improved. However, it was also apparent that the results of the best 12-lead ECG computer programs proved to be almost as accurate as the best of seven cardiologists in classifying seven main disease categories, i.e., normal, left, right and biventricular hypertrophy, anterior, inferior and combined myocardial infarction. Evaluation of rhythm statements and conduction disturbances was not included in the study. The data collection is still being pursued in order to reach over 1,000 cases. In this way a common diagnostic database is being established for comparative testing of diagnostic computer programs. This should lead to consumer protection and improve the accuracy and reliability of computerized electrocardiography.

Cardiovascular Diseases↗
PubMed1988

The influence of the type of occupation on return to work after myocardial infarction, coronary angioplasty and coronary bypass surgery.

Between January 1980 and December 1983 the medical and social status of 423 patients who were considered candidates for aortocoronary bypass surgery (ACBS) was assessed by a questionnaire, at a mean of 16 months after coronary angiography. Of these patients 54 had refused surgery, 15 were re-operated, 23 had angioplasty and seven had died on the waiting list. After exclusion of these 117 patients, 306 remained, who form the basis of this report. Fifty three patients (17%) had retired before surgery, four (1.3%) had died perioperatively and 19 were on sick-leave for less than three months. Of those who were still employed pre-operatively, 102 (44.3%) went back to work, 85 (37%) had retired and 42 (18%) were on sick-leave for longer than three months. Significant differences were noted between the 102 working and the 85 retired patients as far as medical and social factors are concerned. Of the medical factors, post-operative freedom of symptoms (P less than 0.0001), postoperative exercise tolerance (P less than 0.0001) and completeness of revascularization (P less than 0.05) seemed to have influence on return to work. Of the social factors, age (P less than 0.0001), type of occupation (P less than 0.0002), duration of preoperative absence from work (P less than 0.001) and heavy manual work (P less than 0.05) showed significant differences between the groups. Since duration of preoperative absence from work is the only preoperative factor that can be modified, strategies for improving the return-to-work rate should aim at the shortening of waiting times for coronary angiography and ACBS.

Angioplasty, Balloon↗
PubMed1988

Noninvasive detection of anterior wall asynergies by cardiokymography compared to electrocardiography.

In order to determine the value of cardiokymography in detecting left ventricular (LV) anterior wall asynergies, 80 consecutive patients had a cardiokymogram (CKG) and an electrocardiogram (ECG) on the day prior to coronary angiography. Technically adequate CKGs were obtained in 72 patients (67 men and 5 women, mean age 53 +/- 6.5 years). For validation of regional contraction abnormalities, quantitative LV angiography was used. Stepwise linear discriminant analysis was applied to investigate the diagnostic power of CKG. Sensitivity of the CKG for LV anterior wall asynergy was 67.9% (ECG: 39.6%) and specificity was 68.4% (ECG: 94.7%) on the basis of 1 SD of the mean values of the radial axis shortening of a control group. For 2 SD, the sensitivity was 65.6% (ECG: 56.3%) and the specificity 47.5% (ECG: 90%). By combined testing, the specificity increased to 98.3%, whereas the sensitivity dropped to 26.9%. The improvement of the post-test likelihood for a positive ECG by a positive CKG is especially pronounced in the intermediate prevalence range, whereas for a negative ECG the post-test likelihood can be further decreased by a negative CKG in the intermediate and high prevalence range. The ECG as a single test seems to be the more appropriate noninvasive method for detecting LV anterior wall asynergies; however, the combined use of both ECG and CKG may considerably improve the diagnostic accuracy.

Cineangiography↗
PubMed1983

[Mitral valve insufficiency in coronary heart disease].

On 121 consecutive patients with coronary heart disease coronary angiography and quantitative left ventricular angiography was done with the view to aortocoronary bypass surgery. 24 (20%) had mitral regurgitation (MR) by angiographic criteria, 20 of them had MR grade I/IV, four had MR II/IV. In 23 out of 24 patients with MR quantitative left ventriculography revealed localized contraction disorders. MR was clinically diagnosed in 15 out of 24 patients. In eleven patients (48%) contraction abnormalities were localized in the inferior wall, in five cases (22%) in the anterior wall and in seven cases (30%) both in the anterior and posterior wall. Of the latter group patients with MR showed a significantly lower ejection fraction than patients without MR (p less than 0.05). Furthermore the MR-group showed larger akinetic areas, preferentially located in the inferior segments 0 degrees-240 degrees and in the anterolateral segments 60 degrees-90 degrees. Three vessel disease was more frequent in this group (43%) than in the group without MR (23%). Patients with inferior wall asynergy frequently showed combined stenosis or occlusion of the right and circumflex coronary artery. In conclusion, MR in coronary heart disease is most often associated with localized contraction disorders of the left ventricle; posterior wall infarctions, multiple vessel disease and large akinetic areas are more frequent. However, the hemodynamic significance of MR in patients with chronic myocardial infarction is usually insignificant.

Coronary Angiography↗
PubMed1983

[Electrocardiogram and M-mode echocardiography in the diagnosis of chronic transmural infarct. Correlations and determination of the accuracy of both methods based on quantitative levocardiography].

In a comparative study of 121 consecutive patients who had had coronary angiography for coronary heart disease, the diagnostic informations obtained by M-mode echocardiography and electrocardiography in chronic transmural infarction were compared. Wall excursion by echocardiography did not allow sufficient separation of normal and asynergic segments. Changes in systolic wall thickness, on the other hand, provided satisfactory sensitivity and good specificity in the recognition of segmental contraction disorders: posterior wall thickening of 0.64 and 0.76, respectively, septal thickening of 0.45 and 0.91, respectively. In 53% of patients the ECG and echocardiogram provided findings similar to those by angiography. False-positive findings occurred in 10% of electrocardiograms, 14% of echocardiograms. False-negative findings in the ECG occurred in 13%, in the echocardiogram in 25%. Both methods combined had a specificity of nearly 100% with regard to the diagnosis of posterior-wall and anterior-wall infarction, and a positive predictive value of 0.92 (posterior) and 0.93 (anterior wall infarction). M-mode echocardiography and ECG findings provide reliable diagnosis of both the anterior and posterior wall chronic transmural infarction.

Adult↗
PubMed1983

[Qualitative and quantitative analysis of regional contraction disorders using levocardiograms].

In 74 patients with proven myocardial infarction (typical history and enzymes, diagnostic ECG, and stenosis of the vessel supplying the asynergic region of more than 75%) the results of qualitative analysis of left ventricular cineangiograms were compared to those of quantitative analysis using the radial axis method of Mathes. There was a significant difference in interpretation between the two methods if the physiological movements of the heart were not taken into account in the qualitative analysis. After correction for systolic anterior movement and downward movement of the aortic valve during systole, a mean accuracy of 92% resulted. The radial axis method discriminated well between normokinetic and asynergic wall segments. However, this method proved less useful for the detection of asynergies in the apical, anterobasal, and posterobasal regions. A radial axis angle of between 15 degrees and 20 degrees is considered to be optimal. The quantitative analysis seems to be particularly useful for the interpretation of borderline cases, and should be carried out routinely in addition to the qualitative analysis.

Adult↗
PubMed1983

[Significance of the E point-septum distance for the evaluation of left ventricular function in coronary disease--a study using M-mode echocardiography].

In 121 patients (pts) with angiographically proven coronary artery disease, left ventricular (LV) cineangiograms were quantitatively evaluated. 79 pts showed regional wall abnormalities. In this group the relationship between echocardiographic parameters of global (LV) function (mitral-septal separation, systolic and diastolic diameter, and fractional shortening) and ventriculographic parameters was investigated. Mitral-septal separation showed the best correlation to the angiographic ejection fraction (EF) (r = -0.72). The measurement of this parameter allows the diagnosis of a reduced EF independently of the dilatation of the left ventricle, and is easy to perform and to reproduce. Mitral-septal separation discriminated well between the reference group and all infarction subgroups (posterior wall, anterior wall, and double infarction) with reduced EF. The modification of the mitral-septal separation measurement according to D'Cruz et al. showed no advantage over that proposed by Massie et al. Both are clearly dependent upon septal excursion, which has to be taken into consideration when mitral-septal separation is being evaluated. The sensitivity of mitral-septal separation (greater than 7 mm) for the detection of reduced LV function (less than 55%) was 0.66; the specificity was 0.80. There was greater sensitivity for anterior wall infarctions than for posterior wall infarctions (0.73 vs 0.44). Because of the relatively high number of false negatives, only a pathologic mitral-septal separation is diagnostically useful.

Adult↗