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J Airaksinen

Publications and source records attributed to J Airaksinen.

At least 19 recordsLinked to original sources
PubMed2004

Increased pulse pressure is associated with reduced baroreflex sensitivity.

Although pulse pressure (PP), heart rate variability (HRV) and baroreflex sensitivity (BRS) have been shown to predict cardiovascular events and mortality in various populations, their relationships have not been clarified. We examined these associations in two separate population-based samples of healthy middle-aged subjects. In population 1, data were obtained from 149 subjects (71 men and 78 women) aged 35-64 (mean 47.7) years, and in population 2, from 214 subjects (88 men and 126 women) aged 40-62 (mean 50.5) years. Increased 24-h ambulatory PP was related to decreased cross-spectral BRS independent of age and gender (beta=-0.28, P<0.001 for population 1; beta=-0.22, P=0.003 for population 2). This association remained significant when 24-h ambulatory diastolic blood pressure, body mass index, smoking and alcohol intake were added as covariates in the multivariate analysis. Increased ambulatory PP was also associated with increased beat-to-beat systolic arterial pressure variability. Associations between ambulatory PP and HRV were not significant after controlling for age and gender. Our results suggest that elevated PP does not affect overall HRV, but it interferes with baroreflex-mediated control of the heart rate. This association may be due to a common denominator, such as arterial stiffness, for PP and BRS.

Adult↗
PubMed1997

Lymphocyte responses to Chlamydia antigens in patients with coronary heart disease.

AIMS: To clarify the relationship of Chlamydia pneumoniae infection and coronary atherosclerosis we studied cell-mediated and humoral immune responses to Chlamydia in 93 patients with angiographically confirmed coronary heart disease and in 115 controls without angiographically demonstrable lesions. METHODS AND RESULTS: Cell-mediated responses were analysed by measuring lymphocyte proliferative reactivity to whole elementary body antigens of C. pneumoniae. Control antigens included C. trachomatis and purified protein derivative of tuberculin. Chlamydia-specific antibodies were measured using microimmunofluorescence assay. Marked C. pneumoniae-specific immune reactivity, demonstrated by the high incidence of elevated IgG and IgA antibodies and strong lymphocyte proliferative response, was associated with coronary heart disease in male but not in female patients or controls. In male patients, the cell-mediated responses were strong to C. pneumoniae (median stimulation index 9,6) and to C. trachomatis (stimulation index 6,9). The females with coronary heart disease showed significantly stronger cell-mediated responses to C. pneumoniae (stimulation index 6,5) than to C. trachomatis (3,8; P < 0.001) and were comparable to the controls. CONCLUSION: Marked cell-mediated and humoral immunity to C. pneumoniae in males with coronary heart disease suggest that the immune mechanisms triggered by Chlamydia are a possible contributing factor in the disease pathogenesis of coronary atherosclerosis in males. The Chlamydia-specific cell-mediated responses seem to be predominantly induced by antigenic structures that are similar among different Chlamydia-species.

Antibodies, Bacterial↗
PubMed1997

Elevated circulating levels of inflammatory cytokines in patients with abdominal aortic aneurysm.

The basic feature in the pathogenesis of abdominal aortic aneurysm (AAA) is the degradation of extracellular matrix components. This process is induced partly by cytokines secreted from inflammatory and mesenchymal cells. Circulating levels of inflammatory cytokines were studied in AAA patients and compared with subjects suffering from atherosclerotic disease only. Furthermore, the predictive value of cytokine concentrations was evaluated for aneurysm expansion rate. Circulating levels of interleukin 1 beta (IL-1 beta), interleukin 6 (IL-6), tumor necrosis factor-alpha (TNF-alpha), and interferon-gamma (IFN-gamma) were measured in 50 AAA patients (40 men, 10 women), 42 patients with coronary heart disease (CHD) (23 men, 19 women), and 38 controls whose angiogram was normal (17 men, 21 women). No differences in cytokine concentrations were found between the CHD patients and the controls. AAA disease was found to be associated with significantly higher IL-1 beta and IL-6 concentrations in both male patients (median concentrations of 19.40 pmol/L and 6.45 pmol/L, respectively) and female patients (19.26 pmol/L and 7.99 pmol/L) than in either the CHD patients or the controls (P < .005). TNF-alpha levels were slightly higher in the AAA patients (1.64 pmol/L in the males and 1.59 pmol/L in the females) than in the other groups (P < .05). IFN-gamma levels were elevated significantly in the female AAA patients (3.75 pmol/L) compared with levels found in the other female (P < .05) or male (P < .01) patient groups. The measured cytokine concentrations were not related to the size of the aneurysm or the maximal thickness of the thrombus within the aneurysm. IFN-gamma concentration showed a significant positive correlation to the aneurysm expansion (R = .37, P < .02) and negative correlation to the concentration of aminoterminal propeptide of type III procollagen during 6-month follow up (R = -.42, P < .005). The results show that circulating levels of inflammatory cytokines are elevated in patients with AAA disease, suggesting that the production of these cytokines is increased in these patients compared with CHD patients and controls. Elevated INF-gamma concentrations seem to predict an increased rate of expansion in AAA.

Aortic Aneurysm, Abdominal↗
PubMed1996

Abnormalities in beat-to-beat dynamics of heart rate before the spontaneous onset of life-threatening ventricular tachyarrhythmias in patients with prior myocardial infarction.

BACKGROUND: Beat-to-beat analysis of RR intervals can reveal patterns of heart-rate dynamics, which are not easily detected by summary measures of heart-rate variability. This study was designed to test the hypothesis that alterations in RR-interval dynamics occur before the spontaneous onset of ventricular tachyarrhythmias (VT). METHODS AND RESULTS: Ambulatory ECG recordings from 15 patients with prior myocardial infarction (MI) who had spontaneous episodes of sustained VT during the recording and VT inducible by programmed electrical stimulation (VT group) were analyzed by plotting each RR interval of a sinus beat as a function of the previous one (Poincaré plot). Poincaré plots were also generated for 30 post-MI patients who had no history of spontaneous VT events and no inducible VT (MI control subjects) and for 30 age-matched subjects without heart disease (normal control subjects). The MI control subjects and VT group were matched with respect to age and severity of underlying heart disease. All the healthy subjects and MI control subjects showed fan-shaped Poincaré plots characterized by an increased next-interval difference for long RR intervals relative to short ones. All the VT patients had abnormal plots: 9 with a complex pattern, 3 ball-shaped, and 3 torpedo-shaped. Quantitative analysis of the Poincare plots showed the SD of the long-term RR-interval variability (SD2) to be smaller in all VT patients (52+/-14 ms; range, 31 to 75 ms) than in MI control subjects (110+/-24 ms; range, 78 to 179 ms, P<.001) or the normal control subjects (123+/-38 ms, P<.001), but the SD of the instantaneous beat-to-beat variability (SD1) did not differ between the groups. The complex plots were caused by periods of alternating sinus intervals, resulting in an increased SD1/SD2 ratio in the VT group. This ratio increased during the 1-hour preceding the onset of 27 spontaneous VT episodes (0.43+/-0.20) compared with the 24-hour average ratio (0.33+/-0.19) (P<.01). CONCLUSIONS: Reduced long-term RR-interval variability, associated with episodes of beta-to-beat sinus alternans, is a highly specific sign of a propensity for spontaneous onset of VT, suggesting that abnormal beat-to-beat heart-rate dynamics may reflect a transient electrical instability favoring the onset of VT in patients conditioned by structurally abnormal hearts.

Aged↗
PubMed1996

No evidence for ischemic preconditioning during repeated vessel occlusion in coronary angioplasty.

Coronary angioplasty has been the favoured model in studying ischemic preconditioning in humans, but results have remained controversial, possibly due to some artefacts related to coronary balloon angioplasty as an ischemia model. We examined this issue by monitoring the sequential metabolic, functional and neurohumoral changes during repeated vessel occlusion in coronary angioplasty performed in patients with chronic angina pectoris. Two groups of patients undergoing two successive balloon inflations of approximately 2 min duration were studied. These balloon inflations were preceded by a short inflation performed immediately after introduction of the balloon into the stenosis. The aim of this primary inflation was to establish adequate coronary blood flow with the deflated balloon in the stenosis and to guarantee that the subsequent two balloon inflations were truly comparable in time. Group I consisted of 23 patients, in whom the changes in the degree of angina, pulmonary capillary wedge pressure (PCWP), atrial natriuretic peptide (ANP) and circulating catecholamines during the procedure were studied. The sequential changes in myocardial metabolism were monitored in group II of nine patients by determining the lactate extraction ratios and femoroarterial coronary sinus (Fa-CS) differences in pH and pCO2 before and after each balloon inflation. In group I, PCWP and total catecholamines increased similarly during both balloon inflations, but ANP remained unchanged. In group II patients the lactate extraction ratios turned negative, the Fa-CS pH-differences increased and the pCO2-differences decreased during vessel occlusions, the changes being somewhat more prominent during the second balloon inflation. To study adaptation to ischemia, the group I patients were divided into two subgroups with and without signs of ischemic dysfunction during balloon inflations (PCWP increase > 5 mmHg and < 5 mmHg, respectively), and the group II patients were divided into two subgroups with and without metabolic ischemia (lactate-producers and non-producers). The ANP levels were constantly higher in the patients demonstrating ischemic dysfunction during balloon inflations, but catecholamine levels increased only after the second balloon inflation. The anginal pain experienced by the patients and the signs of metabolic ischemia were identical during both balloon inflations. We conclude that acute ischemic preconditioning does not occur in patients with repeated vessel occlusions of approximately 2 min duration. The patients without ischemia during the procedure had more critical stenoses and pre-existing collaterals. However, other protective mechanisms, such as chronic adaptation at the cellular level or recruitment of new collaterals, cannot be excluded.

Angioplasty, Balloon, Coronary↗
PubMed1994

Increase in cerebral blood flow of right prefrontal cortex in man during orgasm.

The functional anatomy of human emotional responses has remained poorly understood, mainly because invasive experiments in humans are unacceptable due to ethical reasons. The new functional imaging techniques such as positron emission tomography and single photon emission computed tomography have made it possible to study the neurophysiology of living humans noninvasively. We studied the regional cerebral blood flow with semi-quantitative 99mTc-HMPAO single photon emission computed tomography in eight healthy right-handed heterosexual males during organism. The results showed decrease of cerebral blood flow during orgasm in all other cortical areas except in right prefrontal cortex, where the cerebral blood flow increased significantly (P < 0.005).

Adult↗
PubMed1994

Acute ethanol-induced changes in cerebral blood flow.

Using high-resolution single photon emission computed tomography, the authors studied changes in cerebral blood flow (CBF) in six healthy men after the men rapidly consumed intoxicating amounts of ethanol. When the subjects were given intravenous placebo before ethanol intake, regional CBF was significantly increased over baseline in the right prefrontal cortex, but no significant change in CBF was observed when the subjects received intravenous naloxone before ethanol intake. The results indicate that euphoria occurring during acute ethanol intake is associated with activation of the right prefrontal cortex and mediated through the endogenous opioid system.

Alcohol Drinking↗
PubMed1993

Rheumatoid arthritis as a cause of cardiac compression. Favourable long-term outcome of pericardiectomy.

In order to clarify the significance of rheumatoid arthritis (RA) as a cause of cardiac compression, we scrutinized pericardiectomy files of 47 patients over a ten-year period at two university hospitals in Finland. Five patients with RA were found. All the patients with RA were men with seropositive disease and subcutaneous rheumatoid nodules. Two of the patients had pulmonary fibrosis, one had cutaneous vasculitis and three had had rheumatoid pleurisy. There was a mean delay of 10 months from the first cardiac symptom to the diagnosis of cardiac compression, the most common misdiagnosis being primarily a liver disease. On the basis of clinical and operative data, four out of the five patients had constrictive pericarditis and one had an effusive-constrictive form of the disease. The histopathological findings in all cases were consistent with chronic fibrosing pericarditis. A follow-up of seven to seventeen years of four patients has not revealed any signs of recurrent pericardial disease. Our results demonstrate that RA is an important aetiological factor for cardiac compression. The long-term outcome of this manifestation seems to be good after pericardiectomy.

Adult↗
PubMed1993

Intraocular pressure-reducing effect of PhXA41 in patients with increased eye pressure. A one-month study.

PURPOSE: To establish the dose-response relationship for the effect on intraocular pressure (IOP) and side effects during long-term treatment of patients with ocular hypertension with the prostaglandin F2 alpha (PGF2 alpha) analog PhXA41. METHODS: A three-center, randomized, double-masked study where IOP, conjunctival hyperemia, and ocular irritation were followed during a 1-month twice-daily treatment with placebo or 35, 60, or 115 micrograms/ml PhXA41 in 60 patients with ocular hypertension, primary open-angle glaucoma, or capsular glaucoma. RESULTS: The three concentrations of PhXA41 reduced the average IOP between 31% and 38% during the second day of treatment, with only a weak dose-response relationship. The initial effect declined somewhat during the first 2 weeks of treatment but then remained at the same level for the rest of the study, with a pressure reduction of approximately 20% for all three concentrations. On the second day of treatment, mild conjunctival hyperemia could be observed in most treated patients. Nineteen of 45 PhXA41-treated patients, compared with 2 of 15 placebo-treated patients, reported to have mild to moderate ocular irritation. These side effects became less pronounced during the study, and at the end there was little difference in the degree of conjunctival hyperemia between placebo- and drug-treated eyes, and no drug-related ocular irritation was reported with the two lowest concentrations of PhXA41. CONCLUSIONS: It is confirmed that the PGF2 alpha analog PhXA41 is a major improvement with respect to the effect-side effect relationship and that it may become a valuable new agent for the treatment of glaucoma.

Adult↗
PubMed1992

Neuroretinal rim area measurements by configuration and by pallor in ocular hypertension and glaucoma.

PURPOSE: The purpose of this study is to examine the differences between measurements of neuroretinal rim area of the optic disc defined by configuration and by pallor. METHODS: One hundred seventy-one patients were studied (59 with glaucoma, 96 ocular hypertensive patients, and 16 controls). The magnification-corrected neuroretinal rim area was measured from black-and-white stereoscopic paper prints. The central area of pallor was measured using computer-assisted image analysis techniques. The percentage of central area of pallor was converted into mm2, and an estimate of neuroretinal rim area defined by color was calculated. RESULTS: The correlation between the measurements of neuroretinal rim area by configuration and by pallor was statistically highly significant (r = 0.89, P less than 0.0001). No consistent differences between measurements were found in different diagnostic groups, or in different stages or types of glaucomatous optic disc abnormality. The correlation of changes of both measurements during a 9-year follow-up period also was statistically significant (r = 0.68, P less than 0.001). CONCLUSION: In clinical routine measurements of the neuroretinal rim area, using both configuration and pallor definition does not seem to add to the information.

Adult↗
PubMed1991

Changes in myocardial energy metabolism in elective coronary angioplasty.

STUDY OBJECTIVE: The aim was to investigate the effect of coronary angioplasty on myocardial energy metabolism, and to assure the safety of the procedure in patients with coronary heart disease. DESIGN: Before angioplasty a catheter was introduced into the coronary sinus. Blood samples were taken simultaneously from femoral artery and coronary sinus before balloon inflation, upon balloon deflation, and two minutes later, and arteriovenous differences in myocardial substrates, pH, PCO2, oxygen saturation, and adenosine catabolites were determined. PATIENTS: 14 patients with angiographically documented coronary artery disease with lesions in the left coronary artery suitable for elective coronary angioplasty were included in the study. RESULTS: During balloon inflation the positive femoroarterial-coronary sinus difference of lactate turned negative, from 0.21(SEM 0.05) mM to -0.10(0.11)mM, p less than 0.02. At the same time pH and PCO2 differences increased: from 0.04(0.00) U to 0.07(0.01) U, p less than 0.01, and from -1.15(0.10) kPa to -1.41(0.10) kPa, p less than 0.01, respectively. The changes were, however, transient and the arteriovenous differences in these metabolic variables rapidly returned towards preinflation levels after balloon deflation. The femoroarterial-coronary sinus concentration differences in glucose and free fatty acids became positive in coronary angioplasty. The energy state remained good during the procedure as assessed from the negligible net efflux of adenosine and its degradation products. CONCLUSIONS: Elective coronary angioplasty can be performed without any persistent derangements in myocardial metabolism, and may in fact lead to improvement of utilisation of some myocardial substrates. Lactate appears to be a more sensitive indicator of short term ischaemia than adenosine degradation products.

Adenosine↗