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Eva Nylander

Publications and source records attributed to Eva Nylander.

11 recordsLinked to original sources
PubMed2006

Feature extraction for systolic heart murmur classification.

Heart murmurs are often the first signs of pathological changes of the heart valves, and they are usually found during auscultation in the primary health care. Distinguishing a pathological murmur from a physiological murmur is however difficult, why an "intelligent stethoscope" with decision support abilities would be of great value. Phonocardiographic signals were acquired from 36 patients with aortic valve stenosis, mitral insufficiency or physiological murmurs, and the data were analyzed with the aim to find a suitable feature subset for automatic classification of heart murmurs. Techniques such as Shannon energy, wavelets, fractal dimensions and recurrence quantification analysis were used to extract 207 features. 157 of these features have not previously been used in heart murmur classification. A multi-domain subset consisting of 14, both old and new, features was derived using Pudil's sequential floating forward selection (SFFS) method. This subset was compared with several single domain feature sets. Using neural network classification, the selected multi-domain subset gave the best results; 86% correct classifications compared to 68% for the first runner-up. In conclusion, the derived feature set was superior to the comparative sets, and seems rather robust to noisy data.

Aged↗
PubMed2006

Thirty-year electrocardiographic follow-up after repair of tetralogy of Fallot or atrial septal defect.

BACKGROUND AND PURPOSE: Knowledge about long-term electrocardiographic changes after surgery for congenital heart disease is limited. METHODS: Eleven patients with corrected tetralogy of Fallot (ToF) and 14 with corrected atrial septal defect (ASD) were followed up at 20 and 30 years after surgery. RESULTS: Approximately 50% of the ASD group developed prolonged QRS duration. In the ToF group, 7 increased QRS duration by more than 20 milliseconds. Nearly all had right bundle-branch block, and 30% of them also had bifascicular block. Two in the ASD group developed first grade atrioventricular block. Five ASD and 6 ToF had prolonged corrected QT duration in the late postoperative phase. CONCLUSIONS: Even after primarily good results of surgery in congenital heart disease, unknown late effects may occur not only in complex lesions such as ToF but also after ASD correction. Regular medical checkups are important after surgical correction in congenital heart disease.

Adolescent↗
PubMed2006

Rupture of a synthetic VSD patch 28 years after total correction of Fallot's anomaly.

Patients operated on for complex congenital heart malformations need continuous follow-up. We present a male patient born in 1948 with Fallot's anomaly. A total correction was performed when he was 21 years old. Twenty-eight years after the operation, at routine follow-up, he presented with a significant left-to-right shunt because of a new ventricular septal defect. During the operation we found the original patch to be fractured with a central perforation. The patient received a new patch and has been without any clinical symptoms since.

Adult↗
PubMed2005

Are patients with isolated chronic aortic regurgitation operated in time? Analysis of survival data over a decade.

BACKGROUND: Patients suffering from chronic isolated aortic regurgitation have a less favorable outcome than patients with aortic stenosis. According to international recommendations, these patients should undergo surgery as soon as left ventricular function begins to deteriorate, that is, surgery is not to be postponed until clinical symptoms become relevant. HYPOTHESIS: The study was undertaken to evaluate how satisfactory our timing of surgery was, as reflected by survival data. METHODS: Survival was studied retrospectively in a consecutive series of patients undergoing surgery for chronic isolated aortic regurgitation during a 10-year period in our institution. Results were compared with data from the literature. By excluding patients with aortic aneurysms and acute endocarditis, we formed a homogeneous patient group of 88 subjects. RESULTS: Thirty-day mortality was 1% and late mortality after a mean follow-up period of 6 years was 11%. Compared with survival data from an earlier study in which the patient population was similar and resided in the same geographic area, the results in our patient group seem to be better. It is noteworthy that despite a strong effort to recommend surgery at an earlier stage of the disease than previously, 35% of the patients had moderate or severe left ventricular dysfunction preoperatively because of late referrals. CONCLUSION: This stresses the importance of early detection and careful preoperative follow-up with noninvasive methods in patients with aortic regurgitation.

Adult↗
PubMed2005

Left ventricular involvement in arrhythmogenic right ventricular cardiomyopathy - a scintigraphic and echocardiographic study.

BACKGROUND: Left ventricular involvement in arrhythmogenic right ventricular cardiomyopathy (ARVC) is a common finding in autopsy studies. In clinical studies using myocardial scintigraphy, MRI and echocardiography, contradictory results have been reported. In this study, we therefore investigated a group of 15 patients with ARVC using thallium-201 (Tl) single-photon emission tomography (SPECT) and echocardiography including assessment of mitral annular motion with M-mode and pulsed tissue Doppler. METHODS: Exercise and rest Tl-201 SPECT were performed in 15 patients with ARVC. The time from diagnosis of the disease varied from less than 1-16 years. All patients fulfilled the established diagnostic criteria for ARVC. An echocardiographic examination, including assessment of left and right ventricular motion and measurements of the mitral annulus motion with M-mode and pulsed tissue Doppler was performed in the patients and in 25 normal subjects. RESULTS: Tl-201 uptake defects in the left ventricular myocardium were present in all except one patient (93%). The uptake defects were predominantly located to the anteroseptal and basal posterior segments. Wall motion abnormalities were seen in the same segments, and in addition to this, in the septal area. In line with this, the total amplitude and the peak systolic velocity of mitral annular motion at the septal point were significantly decreased in the patients compared with the control group. CONCLUSIONS: Our data show that left ventricular involvement is common in ARVC. Tl-201 SPECT and echocardiographic abnormalities were seen not only in patients with long-lasting symptoms but also in asymptomatic patients and in those with short duration of symptoms.

Adult↗
PubMed2002

Long-term follow-up of patients treated with an implantable left ventricular assist device as an extended bridge to heart transplantation.

Four patients were given the TCI implantable left ventricular assist device as a bridge to heart transplantation. The median treatment time was 541 days (range 462 to 873 days), with a total of 2,417 treatment days. The patients were followed with exercise tests and echocardiography 3 to 18 months after implantation. An invasive method was used for quantification of inflow valve incompetence.

Echocardiography↗
PubMed2002

The validity of the Computer Science and Applications activity monitor for use in coronary artery disease patients during level walking.

The principal aim of the present study was to examine the validity of the Computer Science and Applications (CSA) activity monitor during level walking in coronary artery disease (CAD) patients. As a secondary aim, we evaluated the usefulness of two previously published energy expenditure (EE) prediction equations. Thirty-four subjects (29 men and five women), all with diagnosed CAD, volunteered to participate. Oxygen uptake (VO2) was measured by indirect calorimetry during walking on a motorized treadmill at three different speeds (3.2, 4.8 and 6.4 km h-1). Physical activity was measured simultaneously using the CSA activity monitor, secured directly to the skin on the lower back (i.e. lumbar vertebrae 4-5) with an elastic belt. The mean (+/- SD) activity counts were 1208 +/- 429, 3258 +/- 753 and 5351 +/- 876 counts min-1, at the three speeds, respectively (P < 0.001). Activity counts were significantly correlated to speed (r = 0.92; P < 0.001), VO2 (ml kg-1 min-1; r = 0.87; P < 0.001) and EE (kcal min-1; r = 0.85, P < 0.001). A stepwise linear regression analysis showed that activity counts and body weight together explained 75% of the variation in EE. Predicted EE from previously published equations differed significantly when used in this group of CAD patients. In conclusion, the CSA activity monitor is a valid instrument for assessing the intensity of physical activity during treadmill walking in CAD patients. Energy expenditure can be predicted from body weight and activity counts.

Acceleration↗
PubMedDate not supplied

The effect of rear-wheel position on seating ergonomics and mobility efficiency in wheelchair users with spinal cord injuries: a pilot study.

This study analyzed the effect of rear-wheel position on seating comfort and mobility efficiency. Twelve randomly selected paraplegic wheelchair users participated in the study. Wheelchairs were tested in two rear-wheel positions while the users operated the wheelchair on a treadmill and while they worked on a computer. Propulsion efficiency, seating comfort, and propulsion qualities were registered at different loads during the treadmill session. During the computer session, pelvic position, estimated seating comfort, and estimated activity performance were measured. The change in rear-wheel position affected wheelchair ergonomics with respect to weight distribution (p < 0.0001) and seat inclination angle (position I = 5 and position II = 12). These changes had a significant effect on push frequency (p < 0.05) and stroke angle (p < 0.05) during wheelchair propulsion. We found no consistent effect on mechanical efficiency, estimated exertion, breathlessness, seating comfort, estimated propulsion qualities, pelvic position, or activity performance.

Adult↗
PubMedDate not supplied

[Sudden cardiac death in athletes is usually caused by undiagnosed heart disease. Cardiac screening of young athletes under discussion].

Sudden death during exercise in young athletes is usually caused by previously undiagnosed heart disease. The most frequent underlying diseases are hypertrophic cardiomyopathy, coronary artery anomalies and arrhythmogenic right ventricular cardiomyopathy. The possibility of carrying out screening to prevent these tragic cardiac deaths in young athletes has been discussed. A history of sudden cardiac death at a young age among relatives and/or the occurrence of exercise related symptoms in the active sportsperson may identify some of the individuals at risk. A pathological ECG is also a risk factor, especially in combination with a history of abnormal findings upon physical examination. For a correct evaluation of the young athlete, it is important to be aware of the normal variation of cardiac findings in athletes ("athlete's heart").

Adult↗