Search PubMed⌕ Search

Biomedical subjects

H Leinonen

Publications and source records attributed to H Leinonen.

At least 37 records · Page 2Linked to original sources
PubMed1995

Reversal of autonomic derangements by physical training in chronic heart failure assessed by heart rate variability.

Decreased heart rate variability has been associated with chronic congestive heart failure (CHF). We evaluated the effect of physical training on heart rate variability in 20 patients with CHF (NYHA class II-III) randomized to training (n = 8) and control (n = 12) groups. The training group underwent 3 months of physical training, by exercising on a bicycle ergometer for 30 min three times a week at a load corresponding to 50-60% of their peak oxygen consumption. Heart rate variability was assessed from 20-h ambulatory ECG recordings in the frequency domain, determined by high (0.15-0.40 Hz), low (0.04-0.15 Hz) and very low frequency (0.008-0.04 Hz) components. The high frequency component increased by 22-55% in the training group during the day (P = 0.0001) but not at night. The increase was seen during both sedentary and active periods. The low frequency/high frequency ratio attenuated in the training group during the day (P = 0.05) whereas an increase was seen in the control group throughout the day (P = 0.0003). Training lengthened the exercise duration by 71% at a submaximal workload (P = 0.01) and tended to increase the peak oxygen consumption by 15% (P = 0.09). These remained unchanged in the control group. In conclusion, physical training, which improves exercise capacity, ameliorates the autonomic derangement in CHF by increasing the parasympathetically mediated component of heart rate variability. It may thus influence favourably the prognosis of the disease.

Adult↗
PubMed1992

Inherited idiopathic dilated cardiomyopathy with multiple deletions of mitochondrial DNA.

Idiopathic dilated cardiomyopathy (DCM) is often familial, but the pathogenetic mechanisms of DCM are unknown. We report a woman and her son who both died of DCM. The son's cardiac and skeletal muscles showed a high proportion of mitochondrial DNA (mtDNA) with multiple large deletions by Southern-blot hybridisation and polymerase chain reaction analyses. Amplification of the mother's cardiac mtDNA from 20-year-old paraffin-embedded sections showed that she also had deletions of mtDNA. These data suggest that a subgroup of inherited DCMs is associated with mtDNA mutations.

Adolescent↗
PubMed1992

Exclusion of coronary artery disease by exercise thallium-201 tomography in patients with aortic valve stenosis.

In many patients with valvular aortic stenosis (AS), management decisions may be possible without invasive studies if coexistent coronary artery disease (CAD) can be ruled out noninvasively. The use of thallium-201 single-photon emission computed tomography to the exclusion of CAD was studied in 44 patients aged 41 to 78 years with AS. In addition to cardiac catheterization and selective coronary angiography, patients underwent a cardiac ultrasound study and thallium-201 myocardial perfusion imaging at rest and after bicycle ergometer exercise. Two thirds of the patients had critical AS (valve area index less than or equal to 0.5 cm2/m2) but none had left ventricular systolic dysfunction. Twenty-one patients had angiographically significant CAD (greater than or equal to 50% diameter stenosis in greater than or equal to 1 coronary artery), whereas 23 had either a fully normal angiogram (n = 17) or mild (less than 50%) stenoses (n = 6). Each patient with significant CAD had an abnormal thallium-201 tomogram, either a strictly segmental perfusion defect (n = 19), or a patchy nonsegmental abnormality (n = 2); however, 10 of 23 patients free of significant CAD had similar results. Thus, the sensitivity and specificity of an abnormal scintigram were 100 and 57%, respectively. If only segmental perfusion defects typical of CAD had been considered abnormal, then the sensitivity of the test would have been 90% and the specificity 70%. Patients with false abnormal scintigrams had more severe AS and more angiographically nonsignificant CAD than those with true normal findings.(ABSTRACT TRUNCATED AT 250 WORDS)

Aortic Valve Stenosis↗
PubMed1992

Ineffective ventilation during exercise in patients with chronic congestive heart failure.

The pathophysiologic mechanisms causing exertional breathlessness in patients with chronic congestive heart failure (CHF) are not fully understood. Therefore, we have studied whether the ventilation in such patients is ineffective during exercise. Thirteen patients with treated chronic CHF (New York Heart Association class II-IV) and eight healthy controls underwent a maximal bicycle ergometer test with continuous analysis of expired air and frequent arterial blood sampling for gas and lactate analysis. All subjects were non-smokers and none had any signs of a pulmonary disease. Peak O2 consumption of the patients was 14.9 +/- 5.3 ml min-1 kg-1 and that of controls 33.6 +/- 7.5 ml min-1 kg-1. In patients with CHF the ratio of pulmonary dead space to tidal volume was significantly elevated at peak exercise compared with that of the controls (0.36 +/- 0.08 vs. 0.20 +/- 0.07, P less than 0.05). The ventilatory equivalent for CO2 (VE:VCO2) was also significantly higher in patients than in controls during exercise (P less than 0.05). Furthermore, both the ventilatory equivalents for CO2 and O2 (VE:VO2) had a significant inverse correlation with peak O2 consumption (P less than 0.001 for VE:VCO2 and P less than 0.05 for VE:VO2), O2 consumption at anaerobic threshold (P less than 0.01) and O2-pulse (P less than 0.001) among the patients. During exercise the arterial PO2 and PCO2 remained normal in patients and controls. These data indicate that in patients with chronic CHF wasted ventilation is pathologically increased during exercise, and this is related to the severity of the disease. Chronic CHF is not associated with decreased ventilatory reserve, hypoxaemia or alveolar hyperventilation. The ineffectiveness of ventilation is probably an important cause of exertional breathlessness in patients with CHF.

Adult↗
PubMed1992

Aortic valve replacement in patients aged over 70 years.

During a 12-year period, 58 patients aged over 70 years underwent aortic valve replacement. Sixty-six % of them had pure stenosis, 24% were with combined aortic valve disease, and six patients had only regurgitation. Preoperatively, 81% were in NYHA III and the remaining in NYHA IV. The pressure gradient in the AS-group was 105 +/- 27 mmHg and in combined-group, 99 +/- 32 mmHg. The mean ejection fraction was 54 +/- 14%. Thirty-seven mechanical and 21 biological prostheses were placed. Concomitant procedures consisted of annular dilating plasty for five patients while 16 others had coronary by-pass grafting. Hospital mortality was 12%, with the leading causes being low output syndrome and infection complications. The causes of all late deaths were non-cardiac. During the follow-up period of 2.8 +/- 2.5 years, 74% of patients with mechanical valves and 62% of patients with bioprostheses were free from late complications. Prosthetic valve endocarditis (two patients) and valve failure (one patient) occurred only in patients with tissue valves. Embolic complications were equally distributed between the groups. All patients with mechanical valves were placed on permanent anticoagulation therapy, with two of them developing significant complications. On echocardiographic examination, moderate periprosthetic leakage was found in three patients, two of them having mechanical valves. There was a significant increase in EF and regression of left ventricular hypertrophy. At follow-up examination, all 47 living patients found their performance capacity improved.

Aged↗
PubMed1990

Role of alcohol in recurrences of atrial fibrillation in persons less than 65 years of age.

The role of alcohol in recurrences of atrial fibrillation (AF) was assessed in a consecutive series of 98 patients (75 men) aged less than 65 years. In addition to etiologic assessment using clinical and laboratory methods and echocardiography, the patients' drinking habits were evaluated by recording the amount of alcohol used during the week preceding AF, by responses to the CAGE (Cut, Annoying, Guilt, Eye; see below) questionnaire (a screening test for alcohol abuse) and by selected laboratory tests. Two groups of control subjects were studied: 98 sex- and age-matched patients admitted to the emergency ward for acute illnesses, and 50 subjects selected randomly from the local out-of-hospital population. The mean alcohol consumption among men during the study week was 186 g (median 45 g; range 0 to 2,100 g) among patients, whereas among male hospital and population control subjects it was 86 g (30 g; 0 to 1,050 g) and 94 g (35 g; 0 to 630 g), respectively. When the weekly alcohol consumption was analyzed in 3 categories (0; 1 to 210 g; greater than 210 g), there was a significant difference between AF cases and hospital control patients (p = 0.03), but not between AF cases and population control subjects. Multivariate analysis of data of AF cases and population control subjects showed that alcohol intake and a positive response to 1 or more of the CAGE questions were independently related to AF in men. Other independent risk factors were the presence of heart disease, low serum potassium and lack of sleep or experience of excess psychologic stress, or both.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1990

Double-peaking circadian variation in the occurrence of sustained supraventricular tachyarrhythmias.

We studied 251 patients less than or equal to 65 years of age admitted for treatment of symptomatic supraventricular tachyarrhythmia to assess whether these arrhythmias begin evenly throughout the day or manifest circadian variation in occurrence. The arrhythmias included 152 episodes of atrial fibrillation, 50 episodes of supraventricular reentry tachycardia, 30 episodes of atrial flutter, and 19 cases of ectopic atrial tachycardia. A total of 209 patients could tell the exact time their symptoms had started. In 38 of them (18%), the arrhythmia had begun between midnight and 6:00 AM, in 63 (30%) between 6:01 AM and noon, in 46 (22%) between noon and 6:00 PM, and in 62 (30%) between 6:01 PM and midnight. This distribution differed significantly from uniform occurrence (chi square 8.7, p less than 0.05). Fifty patients were using beta-adrenoceptor blocking agents when the arrhythmia occurred. Compared with the other 159 patients, they had no morning surge of arrhythmias (20% versus 33.3% of episodes between 6:01 AM and noon), but instead a much higher incidence at night (34% versus 13.2% of episodes between midnight and 6:00 AM) (chi square 14.4, p less than 0.005). We conclude that the frequency of onset of sustained supraventricular tachyarrhythmias varies with the time of day, showing nearly equal peaks in the morning and in the evening and a trough at night. The modifying effect of beta-adrenoceptor blockage suggests that many morning arrhythmias are of adrenergic origin while other, probably vagal arrhythmogenic mechanisms, prevail at night.

Adrenergic beta-Antagonists↗
PubMed1990

Effect of propranolol and pindolol on the up-regulation of lymphocytic beta adrenoceptors during acute submaximal physical exercise. A placebo-controlled double-blind study.

The effect of beta-adrenoceptor antagonists, with and without intrinsic sympathomimetic activity, on the regulation of lymphocytic beta adrenoceptors during acute physical exercise was studied. Seven healthy volunteers underwent a graded maximal ergometer test after treatment for 7 days with placebo, propranolol (2 x 80 mg/day), or pindolol (2 x 10 mg/day). Each subject received the three types of drug treatment in a double-blind, randomized fashion, with 3 weeks wash-out periods between the on-drug periods. The mean resting density of lymphocytic beta adrenoceptors was 46 +/- 5 fmol/mg protein (mean +/- SEM) during placebo, 53 +/- 5 fmol/mg protein during propranolol, and 29 +/- 4 fmol/mg protein during pindolol treatment (p less than 0.05, pindolol vs. propranolol). Exercise induced a significant up-regulation of the beta-adrenoceptor density during each treatment modality, but the increment was attenuated during propranolol (mean elevation, 16 +/- 2 fmol/mg protein, p less than 0.05) and pindolol intake (13 +/- 4 fmol/mg protein, p less than 0.02) as compared with the placebo value (56 +/- 13 fmol/mg protein). Moreover, exercise-induced increment of lymphocytic cyclic AMP (cAMP) production was virtually abolished by the two beta-adrenoceptor antagonists. In conclusion, administration of beta-adrenoceptor antagonists is associated with a subnormal up-regulation of the lymphocytic beta-adrenoceptors and alterations in their functioning during heavy physical effort. This attenuation is not modified by intrinsic sympathomimetic activity of the compound.

Adult↗
PubMed1989

Response of the beta-adrenergic system to maximal dynamic exercise in congestive heart failure secondary to idiopathic dilated cardiomyopathy.

In congestive heart failure (CHF), prolonged exposure to high plasma catecholamine levels may reduce the responsiveness of the adrenergic system to physiologic stimuli. In healthy subjects, exercise is known to induce a rapid up-regulation of lymphocytic beta adrenoceptors. Lymphocytic beta-adrenoceptor density, lymphocytic basal and isoproterenol-stimulated cyclic adenosine monophosphate (cAMP) response, plasma catecholamine concentrations and plasma cAMP levels were studied during maximal ergometer exercise in 11 patients with CHF secondary to dilated cardiomyopathy and in 6 healthy control subjects. At rest, there was no difference in the lymphocytic beta-adrenoceptor levels between the patients and control subjects (48 +/- 3 vs 42 +/- 5 fmol/mg protein, respectively). However, the exercise-induced increase in lymphocytic beta adrenoceptors was attenuated in patients when compared with controls (26 +/- 6 fmol/mg protein [56%] vs 75 +/- 16 fmol/mg protein [204%], respectively, p less than 0.02). A subgroup of 4 patients with the lowest exercise capacity (peak oxygen uptake less than 12.5 ml/min/kg) had even more reduced up-regulation compared with the other 7 patients (13 +/- 1 fmol/mg protein [29%] vs 34 +/- 9 fmol/mg protein [71%], p less than 0.05). The lymphocytic cAMP response at rest and during exercise tended to be lower in patients compared with controls, but the differences did not reach statistical significance. The plasma levels of epinephrine and norepinephrine at rest were higher in patients compared with controls, but no difference was found in the exercise values. The plasma levels of cAMP correlated closely with plasma catecholamine levels at rest, but not during exercise.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1989

Primary cardiac tumours--operative treatment of 20 patients.

This report describes a series of 20 patients operated on for a primary cardiac tumour. The majority of the tumours (16) were benign myxomas; 12 of them were located in the left atrium, two in the right atrium and two were biatrial. Two lipomas were found; one was epicardial and the other was located in the left atrium. The only intraventricular tumour was a malignant left ventricular myosarcoma. The propensity of intracardiac tumours to embolize was distinctive. Nine of the 16 myxomas presented with peripheral embolization, and in two patients surgery was complicated by fatal perioperative cerebral embolization of myxomatous tissue. Furthermore, in one patient embolization of a left atrial lipoma necessitated amputation of her left arm before cardiac surgery. Late postoperative recurrences were found in two patients with atrial myxomas. In one of them, reoperation showed that the tumour had grown at that site in the interatrial septum where the original pedicle had been excised. One patient developed severe mitral valve regurgitation and underwent replacement with a prosthetic valve at reoperation. Otherwise our late follow-up study showed that the results of surgery were usually excellent even though mild echocardiographic abnormalities were not uncommon. Our experience emphasizes the embolic potential of intracardiac myxomas and suggests, furthermore, that to avoid recurrences excisions with wide margins should be preferred. Echocardiography is an optimal method for the follow-up of these patients.

Echocardiography↗
PubMed1988

Peripheral arterial disease in heterozygous familial hypercholesterolemia: no difference between patients with and without partial ileal bypass.

We evaluated lower limb arterial circulation in 37 patients with heterozygous familial hypercholesterolemia using strain-gauge plethysmography. Nineteen patients were initially allocated to surgical therapy (ileal bypass operation), and 18 control patients were treated conservatively. After a follow-up period of 3-12 years (mean 10 yrs) the surgically treated patients had significantly lower serum total (9.4 vs. 11.9 mmol/l, P less than 0.001) and LDL (6.2 vs. 8.1 mmol/l, P less than 0.01) cholesterol and apoprotein B levels and higher HDL cholesterol (1.2 vs. 1.0 mmol/l, P less than 0.05) and apoprotein A-I levels compared with controls. There was no significant difference in the prevalence of intermittent claudication (16 vs. 6%) or coronary heart disease (68 vs. 61%) between the operated and control groups. The ankle-arm systolic blood pressure ratio was pathologically low in 53% of the operated and 72% of the control patients, and the toe-arm pressure ratio in 50% and 44%, respectively. These differences or the differences in the mean ankle-arm and toe-arm pressure ratios between the groups were not significant. The toe-ankle pressure gradient was normal in all but 2 patients indicating that atherosclerotic changes predominantly affect the more proximal arteries in familial hypercholesterolemia. Patients with peripheral arterial disease could not be differentiated by serum lipoprotein levels, blood pressure or the presence of coronary heart disease. However, smoking was more prevalent (38% vs. 0%, P less than 0.05) in patients with impaired peripheral circulation. We conclude that asymptomatic peripheral arterial disease is quite common in familial hypercholesterolemia, and that smoking increases its risk.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗