Central wave reflection is associated with peripheral arterial resistance in addition to arterial stiffness in subjects without antihypertensive medication.

BACKGROUND: Augmentation index, a marker of central wave reflection, is influenced by age, sex, height, blood pressure, heart rate, and arterial stiffness. However, the detailed haemodynamic determinants of augmentation index, and their relations, remain uncertain. We examined the association of augmentation index with vascular resistance and other haemodynamic and non-haemodynamic factors. METHODS: Background information, laboratory values, and haemodynamics of 488 subjects (239 men, 249 women) without antihypertensive medication were obtained. Indices of central wave reflection, systemic vascular resistance, cardiac function, and pulse wave velocity were measured using continuous radial pulse wave analysis and whole-body impedance cardiography. RESULTS: In a regression model including only haemodynamic variables, augmentation index in males and female subjects, respectively, was associated with systemic vascular resistance (ß = 0.425, ß = 0.336), pulse wave velocity (ß = 0.409, ß = 0.400) (P < 0.001 for all), stroke volume (ß = 0.256, ß = 0.278) (P = 0.001 for both) and heart rate (ß = -0.150, ß = -0.156) (P = 0.049 and P = 0.036). When age, height, weight, smoking habits, and laboratory values were included in the regression model, the most significant explanatory variables for augmentation index in males and females, respectively, were age (ß = 0.577, ß = 0.557) and systemic vascular resistance (ß = 0.437, ß = 0.295) (P < 0.001 for all). In the final regression model, pulse wave velocity was not a significant explanatory variable for augmentation index, probably due to the high correlation of this variable with age (Spearman's correlation ≥0.617). CONCLUSION: Augmentation index is strongly associated with systemic vascular resistance in addition to arterial stiffness. TRIAL REGISTRATION: ClinicalTrials.gov, NCT01742702 .

The type of the functional cardiovascular response to upright posture is associated with arterial stiffness: a cross-sectional study in 470 volunteers.

BACKGROUND: In a cross-sectional study we examined whether the haemodynamic response to upright posture could be divided into different functional phenotypes, and whether the observed phenotypes were associated with known determinants of cardiovascular risk. METHODS: Volunteers (n = 470) without medication with cardiovascular effects were examined using radial pulse wave analysis, whole-body impedance cardiography, and heart rate variability analysis. Based on the passive head-up tilt induced changes in systemic vascular resistance and cardiac output, the principal determinants of blood pressure, a cluster analysis was performed. RESULTS: The haemodynamic response could be clustered into 3 categories: upright increase in vascular resistance and decrease in cardiac output were greatest in the first (+45 % and -27 %, respectively), smallest in the second (+2 % and -2 %, respectively), and intermediate (+22 % and -13 %, respectively) in the third group. These groups were named as 'constrictor' (n = 109), 'sustainer' (n = 222), and 'intermediate' (n = 139) phenotypes, respectively. The sustainers were characterized by male predominance, higher body mass index, blood pressure, and also by higher pulse wave velocity, an index of large arterial stiffness, than the other groups (p < 0.01 for all). Heart rate variability analysis showed higher supine and upright low frequency/high frequency (LF/HF) ratio in the sustainers than constrictors, indicating increased sympathovagal balance. Upright LF/HF ratio was also higher in the sustainer than intermediate group. In multivariate analysis, independent explanatory factors for higher pulse wave velocity were the sustainer (p < 0.022) and intermediate phenotypes (p < 0.046), age (p < 0.001), body mass index (p < 0.001), and hypertension (p < 0.001). CONCLUSIONS: The response to upright posture could be clustered to 3 functional phenotypes. The sustainer phenotype, with smallest upright decrease in cardiac output and highest sympathovagal balance, was independently associated with increased large arterial stiffness. These results indicate an association of the functional haemodynamic phenotype with an acknowledged marker of cardiovascular risk. TRIAL REGISTRATION: ClinicalTrials.gov NCT01742702.

Association of resting heart rate with cardiovascular function: a cross-sectional study in 522 Finnish subjects.

BACKGROUND: High resting heart rate (HR) is associated with increased cardiovascular risk in general populations, possibly due to elevated blood pressure (BP) or sympathetic over-activity. We studied the association of resting HR with cardiovascular function, and examined whether the hemodynamics remained similar during passive head-up tilt. METHODS: Hemodynamics were recorded using whole-body impedance cardiography and continuous radial pulse wave analysis in 522 subjects (age 20-72 years, 261 males) without medication influencing HR or BP, or diagnosed diabetes, coronary artery, renal, peripheral arterial, or cerebrovascular disease. Correlations were calculated, and results analysed according to resting HR tertiles. RESULTS: Higher resting HR was associated with elevated systolic and diastolic BP, lower stroke volume but higher cardiac output and work, and lower systemic vascular resistance, both supine and upright (p < 0.05 for all). Subjects with higher HR also showed lower supine and upright aortic pulse pressure and augmentation index, and increased resting pulse wave velocity (p < 0.001). Upright stroke volume decreased less in subjects with highest resting HR (p < 0.05), and cardiac output decreased less in subjects with lowest resting HR (p < 0.009), but clear hemodynamic differences between the tertiles persisted both supine and upright. CONCLUSIONS: Supine and upright hemodynamic profile associated with higher resting HR is characterized by higher cardiac output and lower systemic vascular resistance. Higher resting HR was associated with reduced central wave reflection, in spite of elevated BP and arterial stiffness. The increased cardiac workload, higher BP and arterial stiffness, may explain why higher HR is associated with less favourable prognosis in populations.

Allelic variant of NOS1AP effects on cardiac alternans of repolarization during exercise testing.

INTRODUCTION: A repolarization abnormality manifested as T-wave alternans (TWA) in electrocardiogram (ECG) predicts cardiovascular mortality. A common variant in the NOS1AP gene is associated with mortality and QT interval duration, possibly in a gender-specific manner, but data is lacking on potential association with TWA. This study tested association between rs10494366 in NOS1AP and both TWA and 4-year mortality. MATERIAL AND METHODS: A total of 1963 Finnish Cardiovascular Study participants (36.6% female, 57.1 ± 13.0 years) were genotyped and their maximal TWA values were measured from continuous ECG recordings during clinical exercise test at rest, exercise and recovery. RESULTS: We observed a significant gender-specific effect of NOS1AP genotype on TWA. In all subjects, there was no statistically significant difference between the three genotypes (TT, TG, GG) in the responses of TWA over the entire exercise test (time-by-genotype interaction p = 0.057). In women, after adjustment for age, coronary heart disease and ß-blocker medication status, changes of TWA over different phases of exercise test were significantly associated with NOS1AP genotype (time-by-genotype interaction p = 0.001). In men, NOS1AP rs10494366 was not associated with TWA. During follow-up (mean 47 months), 113 patients died. NOS1AP rs10494366 was not a statistically significant predictor of mortality. CONCLUSION: The NOSIAP variant rs10494366 influences TWA and TWA response during clinical exercise test in females. Gender-specific effects have also been previously reported for the influence of the variant on QT interval. If replicated, these findings should prompt studies to further elucidate the mechanisms underlying the gender differences in NOS1AP effects on repolarization.

Reduced systemic vascular resistance in healthy volunteers with presyncopal symptoms during a nitrate-stimulated tilt-table test.

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT: Nitrates may facilitate syncope through various pathways, but the precise mechanism of nitrate-induced syncope is still under debate. The purpose of the present study was to compare the underlying haemodynamic mechanisms in subjects without and with presyncopal symptoms during a nitroglycerin-stimulated tilt-table test. WHAT THIS STUDY ADDS: A major decrease in systemic vascular resistance was documented in subjects with presyncope during 0.25 mg nitroglycerin-stimulated tilt-table test, in the absence of changes in cardiac output. These findings indicated that even a small dose of nitroglycerin significantly decreased arterial resistance and cardiac afterload. AIMS The mechanism of nitrate-induced syncope remains controversial. We examined the haemodynamic changes in healthy volunteers during nitroglycerin-stimulated tilt-table test. METHODS: Continuous radial pulse wave analysis, whole-body impedance cardiography and plethysmographic finger blood pressure were recorded in a supine position and during head-up tilt in 21 subjects with presyncopal symptoms (6 male/15 female, age 43 ± 3 years) after 0.25 mg sublingual nitroglycerin and 21 control subjects (6 male/15 female, age 43 ± 2 years). The drug was administered in the supine position and a passive head-up tilt followed 5 min later. Additionally, nitroglycerin was only administered during head-up tilt in 19 subjects and the haemodynamics were recorded. RESULTS: Supine and upright haemodynamics were similar before nitroglycerin administration in the two groups. During the nitroglycerin-stimulated tilt test, aortic and radial mean blood pressure decreased significantly more in the presyncope group when compared with the controls (P= 0.0006 and P= 0.0004, respectively). The decreases in systemic vascular resistance (P= 0.0008) and heart rate (P= 0.002), and increase in aortic reflection time (P= 0.0002) were greater in the presyncope group, while the change in cardiac index was not different between the groups (P= 0.14). If nitroglycerin was administered during the upright tilt and not in supine position, the haemodynamic changes were quite corresponding. CONCLUSIONS: Presyncopal symptoms during nitrate-stimulated tilt test were explained by decreased systemic vascular resistance and increased aortic reflection time, while cardiac output remained unchanged. These findings indicated reduced arterial resistance in nitroglycerin-induced presyncope.

The severity of acute Puumala hantavirus infection does not predict the long-term outcome of patients.

BACKGROUND/AIMS: We have found greater urinary protein excretion and higher glomerular filtration rate (GFR) and blood pressure in patients 6 years after acute nephropathia epidemica (NE) compared with seronegative controls. The present aim was to establish whether the long-term outcome is determined by the severity of acute illness. METHODS: Serial plasma interleukin-6 (IL-6), tumour necrosis factor-α (TNF-α), creatinine, C-reactive protein, blood cell count as well as 24-hour urinary protein and overnight α(1)-microglobulin and albumin excretions were measured in 37 patients with acute NE. Human leucocyte antigen (HLA)-B, HLA-DRB1, TNF-α(-308) and IL-6(-174) alleles were also analyzed. After 6 years, GFR, blood pressure and urinary protein excretion were examined. RESULTS: There were no associations between the clinical severity of acute NE or the genetic factors determined and the increased GFR, hypertension or 24-hour urinary protein excretion observed 6 years later. The degree of inflammation during the acute phase was higher in patients who had increased urinary excretion of α(1)-microglobulin 6 years later compared with those with no α(1)-microglobulin excretion. CONCLUSION: Neither the severity of acute NE nor the host genetic factors determined the predicted renal function, blood pressure or 24-hour urinary protein excretion 6 years later.

Enhanced predictive power of quantitative TWA during routine exercise testing in the Finnish Cardiovascular Study.

INTRODUCTION: We examined whether quantification of T-wave alternans (TWA) enhances this parameter's capacity to evaluate the risk for total and cardiovascular mortality and sudden cardiac death (SCD). METHODS AND RESULTS: The Finnish Cardiovascular Study (FINCAVAS) enrolled consecutive patients (n = 2,119; 1,342 men and 777 women) with a clinically indicated exercise test with bicycle ergometer. TWA (time domain-modified moving average method) was analyzed from precordial leads, and the results were grouped in increments of 10 microV. Hazard ratios (HR) for total and cardiovascular mortality and SCD were estimated for preexercise, routine exercise, and postexercise stages. Cox regression analysis was performed. During follow-up of 47.1 +/- 12.9 months (mean +/- standard deviation [SD]), 126 patients died: 62 were cardiovascular deaths, and 33 of these deaths were sudden. During preexercise, TWA >or= 20 microV predicted the risk for total and cardiovascular mortality (maximum HR >4.4 at 60 microV, P < 0.02 for both). During exercise, HRs of total and cardiovascular mortality were significant when TWA measured >or=50 microV, with 90 microV TWA yielding maximum HRs for total and cardiovascular death of 3.1 (P = 0.03) and 6.4 (P = 0.002), respectively. During postexercise, TWA >or=60 microV indicated risk for total and cardiovascular mortality, with maximum HR of 3.4 at 70 microV (P = 0.01) for cardiovascular mortality. SCD was strongly predicted by TWA levels >or=60 microV during exercise, with maximum HR of 4.6 at 60 microV (P = 0.002), but was not predicted during pre- or postexercise. CONCLUSION: Quantification of TWA enhances its capacity for determination of the risk for total and cardiovascular mortality and SCD in low-risk populations. Its prognostic power is superior during exercise compared to preexercise or postexercise.

Non-invasive measurement of the haemodynamic effects of inhaled salbutamol, intravenous L-arginine and sublingual nitroglycerin.

AIMS: To examine the effects of salbutamol and L-arginine, two compounds acting largely on the endothelium, and the endothelium-independent agent nitroglycerin on blood pressure, arterial compliance, cardiac function and vascular resistance. METHODS: Continuous radial pulse wave analysis, whole-body impedance cardiography, and plethysmographic blood pressure from fingers in the supine position and during head-up tilt were recorded in nine healthy subjects. Data were captured before and after L-arginine (10 mg mg(-1) min(-1)) or saline infusion, salbutamol (400 microg) or placebo inhalation, and sublingual nitroglycerin (0.25 mg) or placebo resoriblet. RESULTS: The results of all measurements were comparable before drug administration. The effects of inhaled salbutamol were apparent in the supine position: systemic vascular resistance (-9.2 +/- 2.6%) and augmentation index (-4.0 +/- 1.5%) decreased, and heart rate (8.6 +/- 2.5%) and cardiac output (8.8 +/- 3.1%) increased. L-arginine had no clear effects on supine haemodynamics, but during head-up tilt blood pressure was moderately decreased and reduction in aortic reflection time prevented, indicating improved large arterial compliance. Nitroglycerin reduced supine vascular resistance (-6.7 +/- 1.8%) and augmentation index (-7.4 +/- 1.6%), and increased cardiac output (+9.2 +/- 2.7%). During head-up tilt, nitroglycerin increased cardiac output (+10.6 +/- 5.6%) and heart rate (+40 +/- 7.5%), decreased vascular resistance (-7.8 +/- 5.8%) and augmentation index (-18.7 +/- 3.2%), and prevented the decrease in aortic reflection time. CONCLUSIONS: Inhaled salbutamol predominantly changed supine haemodynamics, whereas the moderate effects of L-arginine were observed during the head-up tilt. In contrast, small doses of nitroglycerin induced major changes in haemodynamics both supine and during the head-up tilt. Altogether, these results emphasize the importance of haemodynamic measurements in both the supine and upright positions.

Tubular proteinuria and glomerular filtration 6 years after puumala hantavirus-induced acute interstitial nephritis.

BACKGROUND/AIMS: We previously found increased urinary protein excretion, glomerular filtration rate (GFR) and blood pressure in a retrospective analysis of patients with previous nephropathia epidemica (NE). Here, we evaluated the long-term outcome after NE in a prospectively recruited patient group. METHODS: Proteinuria, GFR and ambulatory 24-hour blood pressure were assessed 4-7 years (mean 6) after acute NE in 37 patients, and these values were compared to those from 38 seronegative controls. RESULTS: Six years after NE, the prevalence of elevated urinary alpha(1)-microglobulin excretion was higher in the patients than controls (9/35 vs. 1/38; p = 0.005). The patients also had higher urinary protein excretion (0.17 +/- 0.05 vs. 0.14 +/- 0.04 g/day; p = 0.006), GFR (119 +/- 19 vs. 109 +/- 14 ml/min/1.73 m(2); p = 0.016) and mean systolic (123 +/- 11 vs. 117 +/- 9 mm Hg; p = 0.012), nighttime systolic (109 +/- 11 vs. 100 +/- 9 mm Hg; p = 0.001) and nighttime diastolic blood pressure (70 +/- 7 vs. 66 +/- 7 mm Hg; p = 0.035) than the controls. CONCLUSIONS: These results confirm our previous findings of a higher prevalence of tubular proteinuria and increased urinary protein excretion, GFR and systolic blood pressure 6 years after acute NE.

Analysis of cardiovascular responses to passive head-up tilt using continuous pulse wave analysis and impedance cardiography.

OBJECTIVE: To non-invasively measure central haemodynamics, arterial stiffness, cardiac function and vascular resistance, with the subject in the supine position and during head-up tilt, in order to examine the haemodynamic changes associated with alterations in the augmentation index, and to investigate repeatability and reproducibility of the measurement protocol. MATERIAL AND METHODS: Thirty-three healthy volunteers (21-51 years) were investigated using continuous pulse wave analysis from the radial artery with a tonometric sensor, whole-body impedance cardiography and plethysmographic blood pressure (BP) recordings from the fingers. The measurements were performed with the subject supine and during passive head-up tilt, and repeated during the same session and on four separate days. RESULTS: During the head-up tilt, diastolic BP (5.2+/-0.6%), heart rate (27.6+/-1.9%) and vascular resistance (12.5+/-1.7%) increased (all p<0.05), while systolic BP (-3.2+/-0.6%), aortic pulse pressure (-23.3+/-1.4%), augmentation index (-11.6+/-0.7%), aortic reflection time (-7.0+/-1.0%), ejection duration (-21.4+/-0.7%), stroke volume (-26.1+/-1.2%) and cardiac output (-5.0+/-1.5%) decreased (all p<0.05). Augmentation index at rest correlated with aortic systolic BP (r = 0.423), aortic reflection time (r = -0.647), pulse wave velocity (r = 0.287) and age (r = 0.480). The change in augmentation index during head-up tilt correlated with the change in aortic systolic BP (r = 0.469), aortic pulse pressure (r = 0.606), ejection duration (r = 0.374) and heart rate (r = -0.445). According to Bland-Altman and repeatability index analyses, repeatability and reproducibility of the measurements were good during the same session and on separate days. CONCLUSIONS: Combined pulse wave analysis and impedance cardiography with the subject in the supine position and during head-up tilt is a repeatable and reproducible method for comprehensive investigation of the cardiovascular function.

The Duke treadmill score with bicycle ergometer: Exercise capacity is the most important predictor of cardiovascular mortality.

BACKGROUND: The Duke treadmill score, a widely used treadmill testing tool, is a weighted index combining exercise time or capacity, maximum ST-segment deviation and exercise-induced angina. No previous studies have investigated whether the Duke treadmill score and its individual components based on bicycle exercise testing predict cardiovascular death. DESIGN: Two populations with a standard bicycle testing were used: 3936 patients referred for exercise testing (2371 men, age 56 ± 13 years) from the Finnish Cardiovascular Study (FINCAVAS) and a population-based sample of 2683 men (age 53 ± 5.1 years) from the Kuopio Ischaemic Heart Disease study (KIHD). METHODS: Cox regression was applied for risk prediction with cardiovascular mortality as the primary endpoint. RESULTS: In FINCAVAS, during a median 6.3-year (interquartile range (IQR) 4.5-8.2) follow-up period, 180 patients (4.6%) experienced cardiovascular mortality. In KIHD, 562 patients (21.0%) died from cardiovascular causes during the median follow-up of 24.1 (IQR 18.0-26.2) years. The Duke treadmill score was associated with cardiovascular mortality in both populations (FINCAVAS, adjusted hazard ratio (HR) 3.15 for highest vs. lowest Duke treadmill score tertile, 95% confidence interval (CI) 1.83-5.42, P < 0.001; KIHD, adjusted HR 1.71, 95% CI 1.34-2.18, P < 0.001). However, after progressive adjustment for the Duke treadmill score components, the score was not associated with cardiovascular mortality in either study population, as exercise capacity in metabolic equivalents of task was the dominant harbinger of poor prognosis. CONCLUSIONS: The Duke treadmill score is associated with cardiovascular mortality among patients who have undergone bicycle exercise testing, but metabolic equivalents of task, a component of the Duke treadmill score, proved to be a superior predictor.

Predicting arterial stiffness with ambulatory blood pressure: an 11-year follow-up.

No prospective data have been published on whether ambulatory blood pressure (BP) works better than casual measurements in predicting arterial stiffness. This study with 11-year follow-up was launched to evaluate the usefulness of ambulatory intra-arterial BP in predicting pulse wave velocity (PWV). Ninety-seven previously healthy men were recruited from a routine physical check-up at baseline. BP was measured with standard cuff and intra-arterial ambulatory methods. Sixty-seven subjects with no antihypertensive medication were enrolled for a visit after a follow-up of 11 years. Arterial stiffness was estimated with PWV derived with impedance cardiography. Ambulatory 24-h systolic blood pressure (SBP) (r = 0.30, P = 0.01), 24-h mean arterial pressure (r = 0.27, P = 0.03), 24-h pulse pressure (r = 0.27, P = 0.03) and daytime SBP (r = 0.26, P = 0.03) were the best BP variables in predicting future PWV. Casual BP values did not bear significant correlations with future PWV. In hierarchical regression analysis, the best predictive value for future PWV was achieved with the model including ambulatory 24-h SBP, smoking (number of cigarettes) and age (adjusted R(2) = 0.26). In conclusion, to our knowledge, this is the only prospective follow-up study to show that ambulatory BP is superior to casual BP measurement in predicting future PWV.

Hypertonic saline-hydroxyethyl starch solution attenuates fluid accumulation in cardiac surgery patients: a randomized controlled double-blind trial.

BACKGROUND: Significant fluid retention is common after cardiac surgery with the use of cardiopulmonary bypass (CPB). The aim of the study was to evaluate the effects of hypertonic saline-hydroxyethyl starch (HS-HES) solution on fluid accumulation in patients undergoing coronary artery bypass grafting surgery (CABG). METHODS: Fifty adult male patients undergoing coronary bypass surgery were enrolled in this interventional, randomized, double-blinded study to compare HS-HES with saline solution. The study fluid (250 mL) was given into the venous reservoir of the CPB circuit at the time of aortic declamping. RESULTS: Body mass change from the baseline to the first postoperative morning was significantly less in the HS-HES group compared with the control group (3.3 ± 1.5 kg vs. 4.4 ± 1.5 kg, P = 0.022). In the extracellular water (ECW) or ECW-balance, there were no significant differences between the groups. The need for fluids and diuretic medication did not differ between the groups during the perioperative period. CONCLUSIONS: Our study shows that 250 mL of HS-HES solution can reduce perioperative fluid accumulation to some degree in patients undergoing CABG surgery with CPB.

Metabolic syndrome and arterial stiffness: the Health 2000 Survey.

Metabolic syndrome and its components have been associated with arterial stiffness and cardiovascular disease. The objective of this study was to examine the independent influences of metabolic syndrome, its components, and other cardiovascular risk factors on arterial stiffness as well as to compare 2 definitions for metabolic syndrome (National Cholesterol Education Program [NCEP] and International Diabetes Federation [IDF]) in their ability to identify subjects with arterial stiffness. The study population consisted of 401 Finnish men and women aged 45 years and older who participated in a substudy of the Finnish population-based Health 2000 Survey. Pulse wave velocity (PWV) measured by whole-body impedance cardiography was used as a marker of elevated arterial stiffness. In multivariate models, systolic blood pressure, age, waist circumference, and fasting blood glucose (P < or = .001 for all) were independent determinants for PWV. In the models including metabolic syndrome instead of its components, the NCEP and IDF definitions were similarly associated with PWV (P < or = .01 for both), the other independent determinants being age, sex (P < .001 for both) and plasma C-reactive protein concentration (P = .016 and P = .005 in models containing the NCEP and IDF definitions, respectively). Systolic blood pressure, age, waist circumference, and fasting blood glucose level were independently associated with increased arterial stiffness. Metabolic syndrome determined increased arterial stiffness independently of other known cardiovascular risk factors. The NCEP and IDF definitions did not differ in their ability to identify subjects with increased arterial stiffness.

Natriuretic peptides and hemodynamics in preeclampsia.

OBJECTIVE: The purpose of this study was to evaluate the relationship between natriuretic peptides (NT-proANP and NT-proBNP) and hemodynamic parameters in preeclampsia. STUDY DESIGN: This was a cross-sectional study of 19 preeclamptic, 15 chronic hypertensive, and 26 normotensive women in the third trimester of pregnancy. Stroke index (SI), heart rate (HR), cardiac index (CI), systemic vascular resistance index (SVRI), and left cardiac work index (LCWI) were derived by whole-body impedance cardiography. Systolic blood pressure (SAP), diastolic blood pressure (DAP), and mean arterial pressure (MAP) were measured. The plasma levels of NT-proANP and NT-proBNP were determined with radioimmunoassays. RESULTS: NT-proANP and NT-proBNP concentrations were significantly higher in preeclamptic women compared to chronic hypertensive and normotensive pregnancies. Preeclamptic women had lower CI and HR and higher SAP, MAP, and SVRI than the control groups. In preeclampsia NT-proANP correlated significantly with SAP and SVRI; meanwhile, NT-proBNP correlated significantly with SVRI and CI. These correlations persisted in the subgroup of nonmedicated preeclamptic women, except in the case of NT-proBNP and CI. CONCLUSION: High NT-proANP and NT-proBNP concentrations in preeclampsia reflect the strain on the heart caused by high afterload, rather than the function of the heart expressed as SI or CI.

Hemodynamic adaptation during pregnancy in chronic hypertension.

OBJECTIVE: To assess hemodynamic and NT-proANP changes in women with chronic hypertension during pregnancy. METHODS: Stroke volume index (SI), heart rate (HR), cardiac output index (CI), systemic vascular resistance index (SVRI), pulse wave velocity (PWV), and left cardiac work index (LCWI) were measured using whole-body impedance cardiography. Systolic blood pressure (SAP), mean arterial pressure (MAP), diastolic blood pressure (DAP), and pulse pressure (PP) were also measured. Arterial compliance was defined as the SI-to-PP ratio (SI/PP). Hemodynamic parameters and NT-proANP concentrations were assessed during the early and late second trimester, the third trimester, and after delivery in 20 women with essential hypertension and 30 normotensive women. RESULTS: Arterial blood pressure, SVRI, and PWV remained higher during the whole study period in chronic hypertensive compared with healthy pregnancies. In the early second trimester, women with chronic hypertension had significantly lower SI and NT-proANP concentrations than did normotensive women. CONCLUSION: The hemodynamics of chronic hypertension during pregnancy are characterized by persistent high vascular resistance. Lower SI and NT-proANP values found in chronic hypertensive pregnancies during the early second trimester may suggest a reduced intravascular volume increase during pregnancy.

Heart rate variability derived from exercise ECG in the detection of coronary artery disease.

The diagnostic performance of heart rate variability (HRV) analysis from exercise ECG in the detection of coronary artery disease (CAD) is unknown. Bicycle exercise ECG recordings from The Finnish Cardiovascular Study (FINCAVAS) of angiography-proofed CAD patients (n = 112) and a patient group with a low likelihood of CAD (n = 114) were analyzed. HRV parameters (SDNN, RMSSD, Poincaré SD1 and SD2) were calculated from 1 min segments before exercise, during exercise and after exercise. All the parameters were in addition calculated from heart rate (HR)-corrected RR-interval segments. The ST-segment depressions in each stage were also determined. The diagnostic performance of the parameters was evaluated with the area under the receiver operating characteristic (ROC) curve method. The uncorrected HRV parameters showed the best diagnostic performance in the recovery segments but the correlation with HR was also high (SDNN: 0.758/-0.64, RMSSD: 0.747/-0.60; area under the ROC/correlation coefficient). The HR correction decreased the correlation and the diagnostic performance in recovery segments (SDNN: 0.515/-0.12, RMSSD: 0.609/0.20). The diagnostic performance of ST-level at its best was higher than any of HRV parameters (ST-level: 0.795/0.36). According to the results, the HR correction decreased the diagnostic performance of the recovery phase. The HRV parameters calculated from 1 min segments of exercise test ECG were not as capable as traditional ST-segment analysis. In conclusion, the HRV analysis from exercise or recovery phase seems to be inadequate in the detection of CAD.

Age and gender biases in secondary prevention of coronary heart disease in a Finnish university hospital setting.

BACKGROUND AND OBJECTIVES: Several studies have shown that treatment of coronary heart disease (CHD) does not meet the goals set in recommendations. The aim of this study was to investigate the adequacy of CHD drug treatment and secondary prevention measures, particularly with respect to age and gender biases, in a Finnish university hospital setting. METHODS: The participant pool consisted of patients in FINCAVAS (Finnish Cardiovascular Study), which is a cohort study recruiting consecutive patients performing a clinical exercise test at Tampere University Hospital, Tampere, Finland. 802 patients (581 men, 221 women) with a prior diagnosis of CHD recruited between October 2001 and December 2004 were included in the analysis. RESULTS: Only roughly 12% of both men and women had an optimal risk factor profile. High blood pressure and hypercholesterolaemia were more common in women than in men, whereas smoking was more frequent among men. Men used ACE inhibitors (32.9% vs 20.4%, respectively), beta-adrenoceptor antagonists (80.8% vs 68.3%, respectively) and aspirin (acetylsalicylic acid) [69.7% vs 58.8%, respectively] more frequently than women, but the frequency of use of these medications was also not at the recommended levels in men. Risk factor control is poorer in older than younger age groups. CONCLUSIONS: CHD patients, particularly women, who performed an exercise stress test in a university hospital are suboptimally treated.

The p22phox C242T gene polymorphism is associated with a reduced risk of angiographically verified coronary artery disease in a high-risk Finnish Caucasian population. The Finnish Cardiovascular Study.

BACKGROUND: Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase is a major source of the superoxide anion, which may play an important role in the development of atherosclerosis and coronary artery disease (CAD). The p22phox, a component of the NADPH oxidase, is essential for the activation of this enzyme, and intensive expression of the p22phox has been reported in human atherosclerotic arteries. However, studies on the association of the C242T polymorphism in the p22phox gene with CAD have produced conflicting results, and the relation of this polymorphism with CAD is not well known in a population with acquired risk factors enhancing the NADPH-dependent superoxide production. METHODS: As part of the Finnish Cardiovascular Study, a case-control study was conducted with 402 high-risk Finnish Caucasian patients undergoing coronary angiography. Genotyping was performed using the 5' nuclease TaqMan assay. RESULTS: The prevalence of the T allele (TT + TC genotypes) was significantly lower among angiographically verified CAD patients (n = 250) than among control subjects (n = 152, P = .013). In contrast to subjects with the CC genotype, the T allele was found protective against CAD (odds ratio = 0.531, 95% CI 0.331-0.852, P = .009), and the results remained significant after adjustment for other significant coronary risk factors. CONCLUSIONS: The T allele in the C242Tpolymorphism of the p22phox gene had a protective effect against the development of CAD despite the exposure of study subjects to risk factors related to excessive NADPH-dependent superoxide production.

Asymmetric dimethylarginine and hemodynamic regulation in middle-aged men.

The goal of this study was to evaluate the role of asymmetric dimethylarginine (ADMA) in the regulation of hemodynamic functions in hypertensive men. It has been suggested that ADMA, as an endogenous nitric oxide synthase inhibitor, is linked to hypertension and vascular reactivity. Sixty-seven men aged 51.1 years (range, 45-55 years) were studied. Plasma ADMA and symmetric dimethylarginine were determined by high-performance liquid chromatography-tandem mass spectrometry. Blood pressure (BP) was measured by 24-hour ambulatory recordings and casual measurements. Hemodynamic regulation was assessed by noninvasive methods. The nitric oxide production was estimated based on plasma nitrate (NO(3)(-)) determination. Results showed that plasma arginine derivatives or l-arginine/ADMA ratio was not associated with BP values observed during 24-hour monitoring or in casual measurements. Systemic vascular resistance, pulse wave velocity, or cardiac output was not associated with plasma ADMA or plasma NO(3)(-) levels. No association was found between plasma ADMA and NO(3)(-) either. Interestingly, subjects on antihypertensive treatment had lower plasma ADMA concentrations than nontreated subjects (0.30+/-0.08 and 0.36+/-0.11 micromol/L, respectively, P=.04) despite higher BP values. In conclusion, these results suggest that plasma ADMA does not have a determinative role in the regulation of hemodynamic functions in Finnish middle-aged men.