Search PubMed⌕ Search

Biomedical subjects

M Ikäheimo

Publications and source records attributed to M Ikäheimo.

At least 19 recordsLinked to original sources
PubMed2002

Endothelial nitric oxide synthase gene Glu298Asp polymorphism and blood pressure, left ventricular mass and carotid artery atherosclerosis in a population-based cohort.

OBJECTIVE: Decreased production of endothelial nitric oxide (NO) is associated with different cardiovascular pathology. We studied the association between the Glu298Asp polymorphism of the NO producing gene, endothelial nitric oxide synthase (eNOS), and hypertension, left ventricular mass (LVM) and carotid artery intima-media thickness (IMT) in a population-based cohort of hypertensive and control subjects. DESIGN: Cross-sectional case-control study. SETTING: District around Oulu University Hospital, Northern Finland. SUBJECTS AND METHODS: The study population consisted of 600 middle-aged hypertensive subjects (300 men and 300 women) and 600 controls (300 men and 300 women) living in the City of Oulu. The hypertensive subjects were randomly selected by age stratification from the Social Insurance Institute register for reimbursement of antihypertensive medication. For each hypertensive subject, an age- and sex-matched control was randomly selected from the national health register. The overall participation rate was 87.8%. In the present study a total of 1024 subjects were screened. Echocardiographic examinations were performed by a trained cardiologist and carotid ultrasonographic examinations by a trained radiologist. RESULTS: The genotype distributions and allele frequencies between the hypertensive and control subjects and the relationship between the Glu298Asp variant and blood pressure, LVM and carotid artery IMT were determined. No differences in genotype distribution or allele frequencies were found between the hypertensive and control groups (the frequency of the Asp allele 0.299 vs. 0.288, respectively). Also, we could not find any association between the eNOS genotype and the measured cardiovascular complications. CONCLUSIONS: The Glu298Asp variant of the eNOS gene does not seem to be a major risk factor for cardiovascular alterations in the general population.

Alleles↗
PubMed2001

Ear oximetry: a noninvasive method for detection of patent foramen ovale: a study comparing dye dilution method and oximetry with contrast transesophageal echocardiography.

BACKGROUND AND PURPOSE: Patent foramen ovale (PFO) may play an important role as a risk factor for ischemic stroke and some other neurological conditions. There is a need for low-cost and noninvasive methods for the detection of PFO. This study evaluates the accuracy of two simple bedside tests, the dye dilution method and ear oximetry, in the detection of PFO. METHODS: Dye dilution curves and ear oximetry recordings with a noninvasive ear densitometer were obtained from consecutive cryptogenic stroke patients referred for contrast transesophageal echocardiography (TEE). All test results were blindly assessed for the presence of PFO. Sensitivity and specificity were calculated with TEE used as a reference method. kappa statistics were used to measure interrater agreement. RESULTS: Dye dilution curves were obtained from 67 patients. Dye dilution correctly diagnosed 35 of the 46 patients who had PFO in TEE and all the 21 patients without PFO. Thus, the sensitivity (95% CI) of the dye dilution method was 76% (61% to 87%) and its specificity 100% (84% to 100%). Ear oximetry was done on 83 patients. Oximetry correctly diagnosed 45 of the 53 patients who had PFO in TEE and all of the 30 patients without PFO. Thus, the sensitivity of ear oximetry was 85% (72% to 93%) and its specificity 100% (88% to 100%). The interrater agreement was excellent (kappa value 0.94 for dye dilution and 0.90 for oximetry). CONCLUSIONS: Dye dilution and oximetry are both sensitive and specific methods for the detection of PFO. Oximetry has the following primary advantages over the currently available diagnostic methods: it is noninvasive, safe, and inexpensive and causes no discomfort for the patient. We suggest that oximetry could be used as a first-line screening method for PFO in patients with cryptogenic stroke. Ear oximetry also has potential use in epidemiological studies.

Adult↗
PubMed1999

Plasma vasoactive peptides after acute myocardial infarction in relation to left ventricular dysfunction.

We measured plasma concentrations of vasoactive peptides in 32 patients with acute myocardial infarction and evaluated their value as markers of left ventricular dysfunction. Plasma levels of atrial natriuretic peptide (ANP), the N-terminal fragment of proANP (NT-proANP), B-type natriuretic peptide (BNP) and endothelin-1 were measured serially by radioimmunoassays. The infarct size was estimated from the creatine kinase MB release curve. Coronary angiography and left ventricular cineangiography were performed in all patients during hospitalization and 6 months later in 15 patients. Myocardial infarction caused an increase in vasoactive peptides, the highest values for ANP (36.5+/-6.79 pmol/l), NT-proANP (1130+/-170 pmol/l) and endothelin-1 (9.72+/-0.68 pmol/l) being found on admission and those for BNP (56.0+/-7.13 pmol/l) on Day 2. Plasma levels of natriuretic peptides were dependent on infarct size, its location and degree of myocardial dysfunction and that of BNP also on infarct artery patency. Plasma endothelin-1 level was higher in patients with TIMI 3 than TIMI 0-2 flow. Plasma vasoactive peptides remained elevated during the 6-month follow-up period and they were dependent on the degree of myocardial dysfunction. BNP measured on any day of hospitalization showed the best correlation with ejection fraction measured during the acute phase of infarction or at 6 months. The results show that BNP is the best indicator of left ventricular dysfunction after myocardial infarction and its reliability is not dependent on the time point of measurement.

Analysis of Variance↗
PubMed1999

Neurohumoral responses to a single haemodialysis in chronic renal patients.

The effect of volume reduction on vasoactive substances and their role in estimating dry weight in haemodialysis patients was studied. Plasma atrial natriuretic peptide (ANP), catecholamines, antidiuretic hormone, renin activity and serum aldosterone were measured in 12 patients before and after bicarbonate haemodialysis. Haemodynamical changes were registered and cardiac function and diameter of the inferior vena cava were measured by echocardiography before and after dialysis. Plasma concentration of ANP was significantly reduced by haemodialysis from 209 +/- 51 to 69 +/- 13 pg mL(-1) (n = 12, P < 0.05), whereas concentrations of the other hormones were unchanged. The change in the concentration of ANP did not have significant correlation with weight reduction. The concentration of ANP correlated positively with the diameter of the inferior vena cava (r = 0.70, P < 0.05) after dialysis, but not before dialysis. The concentration of ANP before or after haemodialysis or its change during dialysis did not correlate with any other biochemical parameter. The results show that plasma ANP level is decreased after volume reduction in patients with chronic renal failure, whereas other hormonal systems are unresponsive. However, plasma concentration of ANP seems to have no role in estimating dry weight in chronic haemodialysis patients.

Adult↗
PubMed1998

Variants of renin-angiotensin system genes and echocardiographic left ventricular mass.

AIMS: Variants of renin-angiotensin system genes are shown to be associated with cardiovascular pathology. The association between renin-angiotensin system genes and left ventricular mass was investigated in a population-based case-control study. METHODS AND RESULTS: The association between echocardiographic left ventricular mass and both insertion/deletion polymorphism of the angiotensin-converting enzyme gene and the methionine-threonine variant at position 235 of the angiotensinogen gene was studied in a random cohort of 430 hypertensive and 426 control subjects. No differences in the adjusted left ventricular mass values between the different genotypes were seen among either the hypertensive or the control subjects, whether men or women, or in the subgroups of normotensive or physically active subjects. Gene variation had no statistically significant synergistic effect on left ventricular mass values. In control women, the deletion allele of the angiotensin-converting enzyme gene was associated with an increased risk of left ventricular hypertrophy. However, this finding was based on a small number of women with left ventricular hypertrophy and should be interpreted with caution. CONCLUSION: Variations in renin-angiotensin system genes had no major effect on left ventricular mass in this middle-aged population-based cohort of hypertensives and control subjects.

Adult↗
PubMed1997

Collagen scar formation after acute myocardial infarction: relationships to infarct size, left ventricular function, and coronary artery patency.

BACKGROUND: Left ventricular function after acute myocardial infarction (AMI) is determined by the expansion of the infarct zone and remodeling of the noninfarcted myocardium. An occluded infarct-related artery (IRA) is an independent risk factor for remodeling. METHODS AND RESULTS: Changes in myocardial collagen metabolism were evaluated in 36 patients with suspected AMI. The plasma creatine kinase MB fraction and myoglobin release curves were analyzed for assessment of early reperfusion and infarct size. Collagen scar formation was evaluated by measurement of serum concentrations of the aminoterminal propeptide of type III procollagen (PIIINP), the aminoterminal propeptide of type I procollagen (intact PINP), and the carboxyterminal propeptide of type I procollagen (PICP). Plasma renin activity and urine excretion of cortisol and aldosterone were also measured. Coronary angiography and left ventricular cineangiography were performed during early hospitalization. The serum concentration of PIIINP increased from 3.50+/-0.20 to a maximum of 5.08+/-0.36 microg/L (n=32) in the patients with AMI, whereas the concentrations of intact PINP and PICP tended to decrease. The area under the curve (AUC) of PIIINP during the first 10 postinfarction days was larger in patients with severe heart failure or ejection fractions < or = 40% than in those with no heart failure or with an ejection fraction > 40% (P<.05 and P<.01, respectively), and it was also larger in the patients with TIMI grade 0 to 2 flows than in those with TIMI 3 flows (P<.05), despite similar enzymatically determined infarct sizes. No significant correlations between PIIINP and neurohumoral parameters were observed. The AUC of PIIINP and the change in PIIINP during the first 4 days were significantly correlated with indices of cardiac function. CONCLUSIONS: Collagen scar formation after AMI can be quantified by measurement of serum PIIINP concentrations. Scar formation is more prominent in large infarctions causing left ventricular dysfunction and in patients with occluded IRAs.

Adult↗
PubMed1997

Fatal occlusion of the left coronary main stem by a fragment from the femoral artery: a previously unreported complication of cardiac catheterization.

A 59-year-old man with grade III angina pectoris and 80% stenosis of the left anterior descending coronary artery developed an acute total occlusion of the artery during percutaneous transluminal coronary angioplasty (PTCA). Attempts at recanalisation and resuscitation were ineffective, and the patient died. The medico-legal autopsy revealed obstruction of left main coronary artery by a ringshaped piece of arterial wall that had been torn out of the femoral artery at the punction site and driven around the tip of the catheter into the orifice of the left coronary artery, filling it. This kind of complication of PTCA has not been described previously.

Angina Pectoris↗
PubMed1996

Association of lipoprotein cholesterol and triglycerides with the severity of coronary artery disease in men and women.

The differences between the lipid profiles of male and female patients and the effect of plasma lipids on the extent of coronary artery disease were evaluated in 122 angiographically assessed coronary artery disease patients (95 males and 27 females) and 60 controls. Both male and female patients had lower HDL-cholesterol and higher total cholesterol, LDL-cholesterol, triglyceride, VLDL-cholesterol and VLDL-triglyceride concentrations than the controls. The VLDL lipid values did not differ significantly between the male patients with different extent of CAD, whereas the VLDL lipid values of female patients tended to increase with an increasing severity of CAD. High Lp(a) (> or = 35 mg/dl) values were more prevalent in patients with > 50% coronary stenosis compared to patients with < 50% stenosis and the controls (29%, 17% and 12%, respectively). The apolipoprotein E phenotypes and epsilon allele frequencies were similar in the patients and the controls. Low HDL-cholesterol and high LDL-cholesterol are CAD risk factors for both sexes. For women, elevated VLDL-triglycerides seem to be an additional risk factor for CAD.

Adult↗
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↗
PubMed1996

Could Helicobacter pylori infection increase the risk of coronary heart disease by modifying serum lipid concentrations?

OBJECTIVE: To investigate the relation between Helicobacter pylori infection and coronary heart disease (CHD). DESIGN: A case-control study. SETTING: Northern Finland (about 650,000 inhabitants). PATIENTS: 116 patients with angiographically documented CHD and 116 controls matched for age and gender randomly recruited from the register of the Finnish Social Insurance Institute. MAIN OUTCOME MEASURES: The odds ratio (OR) estimates for the association of H pylori infection with CHD. RESULTS: 64% of the CHD patients and 53% of the controls were seropositive for H pylori; the OR adjusted for age and gender was 1.5 (95% confidence interval (CI) 0.9 to 2.5). An additional adjustment for the common risk factors of CHD, including lipid concentrations, in a logistic regression analysis produced an OR estimate of 1.1 (95% CI 0.6 to 2.1). Among the controls, those who were H pylori positive had significantly (P = 0.03) higher concentrations of serum triglycerides than those who were H pylori negative: the trend among the cases was similar, but non-significant. The concentrations of HDL cholesterol tended to be lower in those who were H pylori positive than in those who were H pylori negative, among both the cases and the controls. CONCLUSIONS: The impact of H pylori infection as an independent risk factor for CHD seems to be minor. On the other hand the results are consistent with the hypothesis that H pylori infection might modify the serum lipid concentrations in a way that could increase the risk of CHD.

Adult↗
PubMed1996

De Vega's annuloplasty for tricuspid regurgitation.

A total of 337 patients underwent a mitral or combined mitral and aortic valve operation at the Oulu University Hospital between 1986 and 1992. Of these, 30 (8.9%) patients had De Vega's semicircular annuloplasty performed because of tricuspid regurgitation (TR) which was considered functional in nature. There were five (16.6%) early and seven (23.3%) late deaths during the follow-up period of 10 to 71 months. The preoperative mean New York Heart Association (NYHA) functional class was 3.4, and at follow-up 13 (76.5%) of the survivors were in NYHA CLass I or II. The actuarial survival rate was 37.6% at five years. All the survivors were evaluated echocardiographically and the TR was considered mild in 56.3%, moderate in 25.0% and severe in 18.7% of the cases. Tricuspid annuloplasty using De Vega's semicircular suture technique is a simple and effective procedure in patients with mild to moderate regurgitation. In patients with massive regurgitation, which is usually associated with a massively dilated tricuspid annulus and pulmonary hypertension, annuloplasty should be reinforced using a ring technique. Tricuspid valve replacement is hardly ever needed in the treatment of functional tricuspid regurgitation.

Actuarial Analysis↗