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K Lindvig

Publications and source records attributed to K Lindvig.

At least 19 recordsLinked to original sources

[Contrast echocardiography. Basic principles and clinical applications].

Recent advances in ultrasound technology and intravenous contrast agents have made it possible for contrast echocardiography to move from bench to bedside. Ultrasound contrast agents enhance endocardial border delineation and the Doppler signal, which may improve the diagnostic accuracy of echocardiography in selected patients. The most exciting feature of contrast echocardiography is its capability to achieve a quantitative assessment of myocardial perfusion, and the method may thus provide a range of clinical applications in patients with ischaemic heart disease.

Contrast Media↗

[AIDS and heart disease].

This article reviews cardiac manifestations of AIDS in terms of etiology, pathogenesis, pathoanatomic lesions and heart function. Hypothetically the prevalence of myocarditis and disperse fibrosis of the myocardium are correlated to increasing rates of dilated cardiomyopathy and cardiac insufficiency. Echocardiography has proved to be of value in detecting early abnormalities and should be recommended on broad indications, though aggressive therapy of cardiac abnormalities is of importance to ensure quality of life and surveillance for the patients.

Acquired Immunodeficiency Syndrome↗

Obesity and cancer risk: a Danish record-linkage study.

A cohort of 43,965 obese persons was accrued on the basis of discharge registrations from Danish hospitals, and incidence of cancer in the cohort was compared to that in the Danish population as a whole using indirect standardisation for age and period. Increased incidence was observed for cancer of the uterine corpus independently of age [114 cases, relative risk (RR) = 2.0, confidence interval 1.6-2.4], and for breast cancer in women above the age of 70 (133 cases, RR = 1.2). These findings are consistent with previous studies. In younger women, breast cancer occurred less frequently and ovarian cancer occurred more frequently than expected. Increased incidence was observed for cancers of the oesophagus (26 cases, RR = 1.9) and the liver (58 cases, RR = 1.9), probably reflecting an increased prevalence of excessive alcohol consumption in the cohort. Increased incidence was furthermore observed for cancers of the pancreas (101 cases, RR = 1.7), the prostate (96 cases, RR = 1.3) and the colon (195 cases, RR = 1.2), which may indicate the existence of risk factors which are common to obesity and to these cancers, for example, dietary habits. Kidney cancer was increased in women only. Overall, the incidence of cancer was increased by 16% in the cohort. The results were essentially unchanged by restriction to the subcohort of 8207 persons in whom obesity was the primary discharge diagnosis, and were also similar in the first year of follow-up after hospital discharge. Selection bias is, therefore, not likely to have influenced the results.

Adolescent↗

Quantification of aortic regurgitation by magnetic resonance velocity mapping.

The use of magnetic resonance (MR) velocity mapping in the quantification of aortic valvular blood flow was examined in 10 patients with angiographically verified aortic regurgitation. MR velocity mapping succeeded in identifying and quantifying the regurgitation in all patients, and the regurgitant volume determined with MR velocity mapping agreed well with the grade obtained by aortic root angiography (p < 0.02). The accuracy in quantification of the aortic valvular flow rate was demonstrated by a significant correlation between the stroke volume (ml) measured by MR velocity mapping and calculated from MR imaging of the left ventricular end-diastolic and end-systolic volumes in eight patients (Y = 0.89 x X + 11, r = 0.97, p < 0.001). This finding was confirmed by a good agreement between the net cardiac output (L/min) quantified with MR velocity mapping and simultaneous 125I-indicator dilution measurement in all subjects (Y = 0.89 x X + 0.08, r = 0.82, p < 0.01). In conclusion, MR velocity mapping may be used as a noninvasive tool in the quantification of aortic regurgitation.

Adult↗

Valve area and cardiac output in aortic stenosis: quantification by magnetic resonance velocity mapping.

Valve area and cardiac output were determined with magnetic resonance (MR) velocity mapping in 12 patients with aortic stenosis. Heart catheterization, Doppler echocardiography, and indicator dilution were performed for comparison. Left ventricle could be catheterized in only nine patients; in these cases, MR measured a mean valve area of 1.2 cm2 compared with 0.9 cm2 derived from catheterization data, with a mean difference of 0.2 cm2 between the 2 methods. The limits of agreement were [0.0, +0.5] cm2, less in patients with an important degree of concomitant regurgitation. In the whole material, MR measured a mean area of 1.1 cm2 compared with 1.2 cm2 derived from Doppler echocardiography data, with a mean difference of 0.1 cm2 and [-0.5, +0.6] cm2 as limits of agreement. In 11 patients the cardiac output was quantified by MR to a mean of 4.9 L/min and by indicator dilution to 5.0 L/min, with a mean difference of 0.2 L/min, and [-0.6, +0.8] L/min as limits of agreement. In addition, MR offers the major advance of simultaneous quantification of regurgitant volume in cases of concomitant regurgitation. In conclusion, because the two important prognostic determinants in aortic stenosis--the valvular area and the cardiac output--may be quantified, MR has potential to become a clinical tool in assessment of severity in aortic stenosis.

Aged↗

Reproducibility of cardiac volume measurements including left ventricular mass determined by MRI.

Cardiac volumes including left ventricular mass were determined by magnetic resonance imaging (MRI) in 30 patients using a contiguous multislice technique. Eleven patients were studied on two different days. Intra- as well as interobserver and interstudy variation were evaluated. For volume measurements the standard deviation of differences (SDD) was rather constant, independent of the size of the measured volume indicating lower percentual variability in measuring large volumes. Lowest variability was noticed for left ventricular myocardial mass estimates between observers as well as between studies. In 13 patients left ventricular mass was estimated by this technique as well as by a method using only one long axis and four short axis slices and by two-dimensional echocardiography. Although highly correlated, limits of agreement between the methods were too wide to accept interchangeable clinical use of the methods.

Adult↗

The pattern of cancer in a large cohort of stroke patients.

A cohort of 113,732 stroke patients from Danish Hospital Discharge Registry were, by linkage to the Danish Cancer Registry, found to have developed a total of 5151 cases of cancer in a mean follow-up time of 2.4 years after the diagnosis of stroke. There was no excess of gastric cancer. The present findings fail to support the existence of a common, strong risk factor for stroke and gastric cancer in individuals. In the cohort, more cancer than expected was observed. In particular, a more than ten-fold increase in risk of brain tumours within the first year after stroke diagnosis was observed, suggesting some diagnostic misinterpretation of a brain tumour as a stroke. Minor excesses of cancer of other sites were also found in the first year of follow-up. They are probably due to increased medical surveillance and diagnostic misinterpretation of an underlying malignancy as an incident of cerebrovascular disease, eg through metastatic spread to the brain.

Aged↗

Echocardiographic screening in 24 consecutive AIDS patients.

To assess the prevalence and extent of cardiac abnormalities in patients with newly diagnosed AIDS, 24 consecutive patients admitted for treatment for acute opportunistic infections were examined with echocardiography during hospitalisation. None of the patients had known cardiac disease or were drug abusers. A total of 16 abnormalities were identified in 13 patients (54%). Nine patients had a right ventricular diameter exceeding 26 mm, two patients had a slightly dilated left atrium or left ventricle, respectively, and five had a moderate pericardial effusion (range 2-8 mm). Left ventricular contractility was normal in all patients. Survival rates between AIDS patients with or without cardiac abnormalities were identical. It is concluded that minor cardiac abnormalities are common in AIDS patients with acute opportunistic infection. However, echocardiography in this group of AIDS patients without cardiac complaints gives no important functional or prognostic information as a routine procedure.

Acquired Immunodeficiency Syndrome↗

Cancer occurrence in a cohort of patients treated with cimetidine.

The possible carcinogenic effects of antisecretory agents used in the treatment of gastric and duodenal ulcer were investigated in a population based cohort study of 16,739 patients who were prescribed the H2-antagonist cimetidine between 1977 and 1981. An excess risk for gastric cancer was observed, with a relative risk of about 10 in the first year after beginning use of the drug, which decreased thereafter. A similar pattern was seen for cancers of the colon, pancreas and gall bladder, and for non-Hodgkin's lymphoma. These increased risks probably represent cases in which a malignancy was misdiagnosed as a gastric ulcer. The excess risk for gastric cancer was unaffected by the method of diagnosis, the risk in those who had undergone an endoscopy being similar to those who had been diagnosed by an x-ray examination. A relative risk of 1.5-2.0 was observed for cancer of the respiratory organs, with no effect of latency, indicating that there are common risk factors for peptic ulcer and for lung cancer. Although the observed increases in cancer risk in persons receiving cimetidine is probably caused by factors other than a carcinogenic action of the drug itself, this possibility cannot be ruled out because of the short period of follow up.

Cimetidine↗

Effect of bepridil on metabolic control and insulin secretion in diabetics.

In a double-blind cross-over study bepridil 900 mg followed by 300 mg daily for 11 days was given to 37 insulin (Type I) or non-insulin (Type II)-dependent diabetic patients. It did not modify the metabolic control of the patients as levels of glucose in blood and urine, doses of insulin and oral hypoglycaemic drugs, energy intake, and the number of hypoglycaemic attacks during therapy were unchanged. The serum concentration of C-peptide was not modified in either type of diabetic patient, and serum insulin in the Type I but not in the Type II patients was slightly higher during active drug treatment. No adverse organotoxic or arrhythmogenic effects or changes in possible atherogenic lipid fractions in serum could be demonstrated during bepridil therapy.

Adult↗

Mitral and aortic valvular flow: quantification with MR phase mapping.

When magnetic resonance phase mapping is used to quantitate valvular blood flow, the presence of higher-order-motion terms may cause a loss of phase information. To overcome this problem, a sequence with reduced encoding for higher-order motion was used, achieved by decreasing the duration of the flow-encoding gradient to 2.2 msec. Tested on a flow phantom simulating a severe valvular stenosis, the sequence was found to be robust for higher-order motion within the clinical velocity range. In eight healthy volunteers, mitral and aortic volume flow rates and peak velocities were quantified by means of phase mapping and compared with results of the indicator-dilution technique and Doppler echocardiography, respectively. Statistically significant correlations were found between phase mapping and the other two techniques. Similar studies in patients with valvular disease indicate that phase mapping is also valid for pathologic conditions. Phase mapping may be used as a noninvasive clinical tool for flow quantification in heart valve disease.

Aortic Valve↗