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P Keto

Publications and source records attributed to P Keto.

At least 19 recordsLinked to original sources
PubMed2002

Endovascular treatment of aortic aneurysms in Finland: the first four years' experience.

BACKGROUND AND AIMS: In this study the results of endovascular treatment of aortic aneurysms in Finland are presented and compared to the results of the Eurostar registry. MATERIAL AND METHODS: A total of 229 patients with aortic aneurysm were treated in five different Finnish centres during 1996-2000. The data of these patients were collected prospectively by surgeon or interventional radiologist involved. During the same period of time 2464 patients were registered in the Eurostar registry. RESULTS: The procedure was performed successfully in 97% of patients in Finland, and the 30-day mortality was 0,9%. A graft limb thrombosis was detected in 9% of the patients in Finland. A permanent primary endoleak at the first 30-day control was seen in 23 patients (10%). During the follow-up 17 secondary endoleaks (7%) were detected. A secondary intervention was necessary in 26% of the patients. Three patients (1.3%) had late rupture of the abdominal aortic aneurysm. CONCLUSIONS: According to the Finnish short-time results, endovascular treatment of aortic aneurysms is safe and associated with relatively low morbidity and mortality. The mid-term results are more disappointing with relatively many graft thromboses and endoleaks, and a frequent need of secondary interventions.

Adult↗
PubMed2001

Safety and effectiveness of single- versus triple-dose gadodiamide injection- enhanced MR angiography of the abdomen: a phase III double-blind multicenter study.

PURPOSE: To evaluate the safety and effectiveness of gadodiamide-enhanced magnetic resonance (MR) angiography with single and triple doses in the assessment of abdominal arterial stenoses. MATERIALS AND METHODS: One hundred five patients were included in the randomized, double-blind, phase III multicenter trial. Results of MR angiography with 0.1 mmol/kg and 0.3 mmol/kg doses of gadodiamide were compared with those of digital subtraction angiography (DSA) and according to dose. RESULTS: No serious adverse events were observed. The mean contrast index at the region proximal to the primary stenosis was significantly higher in the triple-dose group (P =.03). Mean 95% CI values for the difference in depicted degree of stenosis between DSA and postcontrast MR angiography improved from -3.4% +/- 4.7 (SD) in the single-dose group to -1.2% +/- 4.7 in the triple-dose group. Mean values for overall image quality on the visual analogue scale improved with the triple dose (P =.02). Confidence in diagnosis was high at postcontrast MR angiography in 88% and 96% of cases in the single- and triple-dose groups, respectively. CONCLUSION: Gadodiamide-enhanced MR angiography performed with single and triple doses is safe and effective for assessing major abdominal arterial stenoses. Although high agreement between MR angiography and DSA was achieved with both doses, triple-dose MR angiography was superior in the evaluations of image quality, degree of arterial stenoses, and confidence in diagnosis.

Abdomen↗
PubMed1999

A prospective study of bone loss and turnover after cardiac transplantation: effect of calcium supplementation with or without calcitonin.

Cardiac transplantation exposes recipients to osteoporosis and increased risk of consequent fractures. The purpose of the present study was to examine the magnitude, timing and mechanism of bone loss following cardiac transplantation, and to establish whether bone loss can be prevented by calcium with or without calcitonin. Thirty patients (29 men, 1 woman), aged 26-68 years (mean 48 years), were randomized into three groups of 10 to receive either no additional treatment, oral calcium 1 g twice daily for 12 months or the same dose of calcium plus intranasal calcitonin 400 IU/day for the first month and then 200 IU/day for 11 months. Bone mineral density (BMD) at the lumbar spine and three femoral sites (femoral neck, trochanter, Ward's triangle) was measured by dual-energy X-ray absorptiometry (DXA) at the time of transplantation and 6 and 12 months later. Markers of bone formation [serum bone-specific alkaline phosphatase (B-ALP), type I procollagen carboxyterminal propeptide (PICP) and aminoterminal propeptide (PINP)] and resorption [serum type I collagen carboxyterminal telopeptide (ICTP)], as well as serum testosterone in men, were assayed before transplantation and at 1 week and 1, 3, 6 and 12 months after transplantation. During the first 6 post-transplant months BMD calculated as a percent change from baseline decreased in the control group by 6.4% (p = 0.014) in the lumbar spine, by 6.0% (p = 0.003) in the femoral neck, by 5.0% (p = 0.003) in the trochanter and by 5.5% (p = 0.130) in Ward's triangle. Between 6 and 12 months a further decline in BMD occurred only at the three femoral sites, ranging from 2.2% to 9.8% (p = 0.004-0.079). In comparison with the control group, the group receiving calcium alone lost less bone in the trochanter between 0 and 6 months (p = 0.019), and the group receiving calcium together with calcitonin lost less bone in the femoral neck (p = 0.068) and Ward's triangle (p = 0.076) between 0 and 12 months. Seven (28%) of 25 assessable patients experienced vertebral compression fractures. Calcium with or without calcitonin had no effect on changes in biochemical parameters; consequently, the three study groups were combined. The markers of bone formation increased, the elevations in mean values being 59% for B-ALP at 1 month (p = 0.009), 152% for PICP at 1 week (p < 0. 0001) and 27% for PINP at 1 week (p = 0.021). After a temporary decline at 3 months B-ALP (p = 0.0002) and PINP (p < 0.0001) at 1 year were nearly doubled compared with baseline values. Throughout the study the marker of bone resorption, serum ICTP, was above normal, with a peak (mean values 67-69% above baseline) at 1 week (p = 0.0002) to 1 month (p < 0.0001). The mean concentration of total testosterone was decreased by 48% (p < 0.0001) 1 week and by 28% (p = 0.0005) 1 month after transplantation, but this was mainly explained by the concomitant drop in serum albumin. High bone turnover underlies bone loss after cardiac transplantation. Bone loss is most rapid during the first 6 post-transplant months. In the upper femur this bone loss may be reduced by treatment with calcium and calcitonin.

Adult↗
PubMed1999

Arrhythmic disorder mapped to chromosome 1q42-q43 causes malignant polymorphic ventricular tachycardia in structurally normal hearts.

OBJECTIVES: The purpose of this study was to provide clinical and anatomical characteristics as well as genetic background of a malignant arrhythmogenic disorder. BACKGROUND: An inherited autosomally dominant cardiac syndrome causing stress-induced polymorphic ventricular tachycardia and syncope in the absence of structural myocardial changes was detected in two families. METHODS: Two unrelated families with six victims of sudden death and 51 living members were evaluated. Resting and exercise electrocardiograms (ECG), echocardiography, magnetic resonance imaging (MRI), cineangiography, microscopic examination of endomyocardial biopsies and a drug testing with a class IC antiarrhythmic agent flecainide were performed. A genetic linkage analysis was carried out to map the gene locus. RESULTS: Of the 24 affected individuals, 10 had succumbed with six cases of sudden death, and 14 survivors showed evidence of disease. Exercise stress test induced ventricular bigeminy or polymorphic ventricular tachycardia in affected individuals. Three children initially examined before 10 years of age developed arrhythmias during a four-year follow-up. Resting ECGs were normal in affected subjects except a slight prolongation of the QT intervals adjusted for heart rate (QTc) (430 +/- 18 vs. 409 +/- 19 ms, affected vs. nonaffected, p < 0.01). Administration of flecainide did not induce ECG abnormalities encountered in familial idiopathic ventricular fibrillation. Ventricular volumes, contractility and wall measurements were normal by echocardiography, right ventricular cineangiography and MRI. Histopathological examination showed no fibrosis or fatty infiltration. The cumulative cardiac mortality by the age of 30 years was 31%. The disease locus was assigned to chromosome 1q42-q43, with a maximal pairwise lod score of 4.74 in the two families combined. Only one heterozygous carrier was clinically unaffected suggesting high disease penetrance in adulthood. CONCLUSIONS: A distinct cardiac disorder linked to chromosome 1q42-q43 causes exercise-induced polymorphic ventricular tachycardia in structurally normal hearts and is highly malignant. Delayed clinical manifestation necessitates repeated exercise electrocardiography to assure diagnosis in young individuals of the families.

Adolescent↗
PubMed1999

A prospective study of bone loss and turnover after allogeneic bone marrow transplantation: effect of calcium supplementation with or without calcitonin.

Transplantation of solid organs including heart, kidney, and liver is associated with rapid bone loss and increased rate of fracture; data on bone marrow transplantation recipients (BMT) are scarce. The purpose of the present study was to examine the magnitude, timing, and mechanism of bone loss following allogeneic BMT, and to study whether bone loss can be prevented by calcium with or without calcitonin. Sixty-nine patients undergoing allogeneic BMT for malignant blood diseases were enrolled into the study. Forty-four (22 women, 22 men) completed 6 months, and 36 patients 1 year follow-up. They were randomized to receive either no additional treatment (n = 22), or oral calcium 1 g twice daily for 12 months (n = 12) or the same dose of calcium plus intranasal calcitonin 400 IU/day for the first month and then 200 IU/day for 11 months (n = 10). Bone mineral density (BMD) at the lumbar spine and three femoral sites (femoral neck, trochanter, Ward's triangle) was measured by dual-energy X-ray absorptiometry (DXA). Bone turnover rate was followed with markers of bone formation and resorption (serum bone-specific alkaline phosphatase (B-ALP), type I procollagen carboxyterminal (PICP) and aminoterminal propeptide (PINP), serum type I collagen carboxyterminal telopeptide (ICTP)). Serum testosterone was assayed in men. Calcium with or without calcitonin had no effect on bone loss or bone markers; consequently the three study groups were combined. During the first 6 post-transplant months BMD decreased by 5.7% in the lumbar spine and by 6.9% to 8.7% in the three femoral sites (P < 0.0001 for all); no significant further decline occured between 6 and 12 months. Four out of 25 assessable patients experienced vertebral compression fractures. Markers of bone formation reduced: B-ALP by 20% at 3 weeks (P = 0.027), PICP by 40% (P < 0.0001) and PINP by 63% at 6 weeks (P < 0.0001), with a return to baseline by 6 months. The marker of bone resorption, serum ICTP was above normal throughout the whole observation period, with a peak at 6 weeks (77% above baseline, P < 0.0001). In male patients serum testosterone decreased reaching a nadir (57% below baseline) at 6 weeks (P = 0.0003). In conclusion, significant bone loss occurs after BMT. It results from imbalance between reduced bone formation and increased bone resorption; hypogonadism may be a contributing factor in men. Bone loss can not be prevented by calcium with or without calcitonin.

Administration, Inhalation↗
PubMed1999

Nonfluoroscopic localization of an amagnetic stimulation catheter by multichannel magnetocardiography.

This study was performed to: (1) evaluate the accuracy of noninvasive magnetocardiographic (MCG) localization of an amagnetic stimulation catheter; (2) validate the feasibility of this multipurpose catheter; and (3) study the characteristics of cardiac evoked fields. A stimulation catheter specially designed to produce no magnetic disturbances was inserted into the heart of five patients after routine electrophysiological studies. The catheter position was documented on biplane cine x-ray images. MCG signals were then recorded in a magnetically shielded room during cardiac pacing. Noninvasive localization of the catheter's tip and stimulated depolarization was computed from measured MCG data using a moving equivalent current-dipole source in patient-specific boundary element torso models. In all five patients, the MCG localizations were anatomically in good agreement with the catheter positions defined from the x-ray images. The mean distance between the position of the tip of the catheter defined from x-ray fluoroscopy and the MCG localization was 11 +/- 4 mm. The mean three-dimensional difference between the MCG localization at the peak stimulus and the MCG localization, during the ventricular evoked response about 3 ms later, was 4 +/- 1 mm calculated from signal-averaged data. The 95% confidence interval of beat-to-beat localization of the tip of the stimulation catheter from ten consecutive beats in the patients was 4 +/- 2 mm. The propagation velocity of the equivalent current dipole between 5 and 10 ms after the peak stimulus was 0.9 +/- 0.2 m/s. The results show that the use of the amagnetic catheter is technically feasible and reliable in clinical studies. The accurate three-dimensional localization of this multipurpose catheter by multichannel MCG suggests that the method could be developed toward a useful clinical tool during electrophysiological studies.

Adult↗
PubMed1998

Minimally invasive coronary artery bypass grafting using the right gastroepiploic artery.

BACKGROUND: Anastomosis of the left internal thoracic artery to the left anterior descending artery without sternotomy and without cardiopulmonary bypass is a standard approach in minimally invasive coronary artery bypass grafting. To expand the indications for minimally invasive coronary artery bypass grafting from one-vessel disease to two-vessel disease, we began to perform anastomosis of the right gastroepiploic artery (RGEA) to the right coronary artery (RCA). METHODS: From February to November 1996, an RGEA graft was used in 25 of the 100 patients who underwent minimally invasive coronary artery bypass grafting at our clinic. Eleven of the patients had only RCA disease and 14 had both RCA and left anterior descending artery disease. One of the operations was a redo coronary artery bypass grafting. The RGEA was anastomosed to the RCA through a laparotomy incision and the left internal thoracic artery was anastomosed to the left anterior descending artery through a left anterior thoracotomy. In 5 patients, the RGEA was lengthened by venous grafting. RESULTS: All patients underwent angiography after operation; 82.6% of the RGEA grafts and all the left internal thoracic artery grafts were functioning well. In three of the four nonvisualized RGEA grafts, the percentage of proximal stenosis of the RCA seen on postoperative angiography was not critical (40%, 50%, and 50%, respectively), allowing significant competitive flow through the native bypassed RCA. The patency of all the RGEA grafts without competitive flow was 95%, with a 95% confidence interval of 75.1% to 99.9%. CONCLUSIONS: The indications for minimally invasive coronary artery bypass grafting could be extended to primary operations in patients with left anterior descending artery and RCA lesions by using both the left internal thoracic artery and the RGEA.

Adult↗
PubMed1996

Effects of angiotensin-converting enzyme inhibition versus beta-adrenergic blockade on aortic stiffness in essential hypertension.

We assessed the effects of 6 months of treatment with an angiotensin-converting enzyme (ACE) inhibitor (cilazapril) or a beta 1-adrenergic blocker (atenolol) on aortic stiffness in essential hypertension. Forty patients (16 women) aged 47 +/- 9 years (mean +/- SD) with baseline systolic and diastolic blood pressures of 162 +/- 15 and 105 +/- 5 mm Hg, respectively, were entered into a double-blind, parallel-group study with cilazapril, 5 mg once daily, or atenolol, 100 mg once daily. The treatment period was preceded by a 4-week placebo washout phase. Aortic elastic modulus (Ep) was determined by cine magnetic resonance imaging (MRI) and indirect brachial artery blood pressure measurements prior to and after 3 weeks and 6 months of therapy. The reductions in systolic and diastolic blood pressures from baseline to 6 months averaged -17 +/- 13 and -10 +/- 6 mm Hg, respectively, with cilazapril and -23 +/- 16 and -14 +/- 6 mm Hg with atenolol. Concomitantly, Ep of the ascending aorta decreased with cilazapril from a median of 2,234 10(3)dyn/cm2 (interquartile range, 866-3,740) to 868 10(3)dyn/cm2 (515-1,486) and with atenolol from a median of 1,611 10(3)dyn/cm2 (895-2,790) to 1,054 10(3)dyn/cm2 (616-1,860). In repeated-measurements analysis of variance, the change in Ep with time was statistically significant (p < 0.001) but the group x time interaction was not. We conclude that 6 months of treatment with either cilazapril or atenolol reduces the stiffness of the ascending aorta in essential hypertension. No statistically significant differences between the effects of the two drugs were observed. The mechanisms and clinical significance of improved aortic distensibility with antihypertensive therapy deserve further study.

Adolescent↗
PubMed1996

[MRI angiography].

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Cardiovascular Diseases↗
PubMed1996

Angiographic 5-year follow-up study of right gastroepiploic artery grafts.

BACKGROUND: The right gastroepiploic artery (RGEA) has been used from 1987 in coronary artery bypass grafting in several clinical studies. However, the published 1- to 5-year patency rates have been dependent on the selection of patients for angiography. METHODS: In our study, the RGEA was used from March 1987 to May 1990 for coronary artery bypass grafting in 31 consecutive patients, 25 male and 6 female. All but 1 patient had triple-vessel disease, and the mean number of distal anastomoses was 3.9 (range, 2 to 5). Internal thoracic artery grafts were used concomitantly in all patients. RESULTS: One early and two late deaths occurred. All but 1 of the 28 surviving patients underwent clinical and angiographic follow-up examinations 3 months and 5 years after the operation. The 5-year patency of RGEA grafts was 82.1%, with a 95% confidence interval of 63.1% to 93.9%. In 4 of the 5 nonvisualized cases, the recipient coronary artery showed proximal stenosis of up to 70%, allowing substantial competitive flow. The 5-year patency of the RGEA graft was near that of the left internal thoracic artery, at 90.3%, and the right internal thoracic artery, at 94.4%; and superior to the 66.7% patency of venous grafts. CONCLUSIONS: At 5-year follow-up, angiography of RGEA grafts showed good function and a smooth lumen, especially if the proximal stenosis was more than 70%.

Abdominal Muscles↗
PubMed1996

Assessment of right and left atrial function in patients with transplanted hearts with the use of magnetic resonance imaging.

BACKGROUND: The purpose of this study was to determine the volumes and cyclic volume changes of the cardiac atria after heart transplantation in physically healthy recipients. METHODS: Ten heart transplant recipients (New York Heart Association grade I) entered the protocol. All operations had been made with classic biatrial anastomoses. Eight healthy volunteers were studied as controls. To measure the volumes of both atria and left ventricular cavity, we used a gradient-echo cine sequence. The 10 mm slices covered both atria over the total cardiac cycle. Images were planimetered, and simultaneous volumes were totalled to give the cavity volume at each time phase. RESULTS: The heart rate of the heart transplant recipients was faster than in controls, which resulted in higher cardiac output. The atrial minimum volumes were significantly larger, and fractional emptying was smaller in transplanted hearts when compared with controls. Reservoir and stroke volumes were smaller and conduit volumes were larger in transplanted hearts than in controls. The atrial filling and emptying rates were lower in heart transplant recipients than in controls. CONCLUSIONS: The classic surgical technique used in heart transplantation results in large atria with decreased volume changes and filling rates even in physically healthy transplant recipients. Magnetic resonance imaging is a reliable tool in assessment of atrial volumes and cyclic function after heart transplantation.

Adult↗
PubMed1994

Left ventricular function in children with the Marfan syndrome.

Aortic dilatation and heart valve lesions are common in the Marfan syndrome but whether primary alterations occur in left ventricular (LV) function has not been studied hitherto. LV size, mass and systolic as well as diastolic function were studied by M-mode and Doppler echocardiography and cine magnetic resonance imaging in 22 Marfan children aged 3.0-15.4 years and in 22 age-matched healthy children. No child had significant valve disease. Heart rate and systolic blood pressure were comparable in the groups but diastolic blood pressure was higher in the controls (67 +/- 7 mmHg vs 62 +/- 8 mmHg, P = 0.030). No statistically significant differences were found in LV size, mass or systolic function. The Marfan children had slower LV peak diameter lengthening rates (106 +/- 27 mm.s-1 vs 132 +/- 29 mm.s-1, P = 0.004), prolonged relaxation times (155 +/- 22 ms vs 140 +/- 19 ms, P = 0.023), slower deceleration of the early transmitral velocity (580 +/- 144 cm.s-1 vs 720 +/- 160 cm.s-2, P = 0.006), and smaller early-to-late peak velocity ratios (1.99 +/- 0.40 vs 2.29 +/- 0.46, P = 0.031). These data indicate that LV early diastolic function (relaxation) is impaired in the Marfan syndrome. Weakened elastic recoil due to the underlying connective tissue abnormality may best explain this novel observation.

Child↗
PubMed1994

Relation of aortic stiffness to factors modifying the risk of atherosclerosis in healthy people.

To identify factors predicting aortic stiffness, we studied the modulus of elasticity of the thoracic aorta in relation to sex, obesity, blood pressure, physical activity, smoking, ethanol consumption, salt intake, and serum lipid and insulin levels in 55 healthy people born in 1954. A transverse cine magnetic resonance image of the thoracic aorta was made, and the modulus of elasticity was determined as brachial artery cuff pulse pressure/aortic strain, where strain was determined as the ratio of pulsatile aortic luminal area change to the diastolic luminal area. The average of measurements made in the ascending and descending aorta was used as the elastic modulus of the thoracic aorta. Habitual physical activity, smoking, and alcohol use were quantified by 2-month prospective daily recording and salt intake by 7-day food records. The aortic elastic modulus ranged from 100 to 2091 10(3) dyne/cm2 (median, 390 10(3) dyne/cm2). In multiple regression analyses, log10 aortic elastic modulus was related directly to mean blood pressure (standardized coefficient [beta] = .37, P = .002), serum high-density lipoprotein cholesterol (beta = .36, P = .012), square root of daily energy expenditure in physical activity (beta = .33, P = .005), and log10 serum insulin (beta = .27, P = .047) and inversely to serum low-density lipoprotein cholesterol (beta = -.26, P = .035). A relation to salt intake was also observed, but the regression slope was dependent on mean blood pressure (P = .005 for interaction). These data suggest that many modifiable constitutional and lifestyle characteristics may contribute to the stiffness of the thoracic aorta.

Adult↗
PubMed1994

Prevalence and predictors of audible physiological third heart sound in a population sample aged 36 to 37 years.

BACKGROUND: A physiological third heart sound (S3) is common in youth but allegedly very rare after the age of 40 years. The mechanism of its disappearance is not known. The aim of this work was to study the prevalence and predictors of physiological S3 in a population-based sample of persons approaching 40 years of age. METHODS AND RESULTS: A random sample of 120 persons born in 1954 was invited; 93 (42 men) entered the study. Their physical activity, alcohol and tobacco consumption, and salt intake were quantified by diary follow-up. The presence of an S3 was determined by auscultation and confirmed by phonocardiography. Left ventricular (LV) size, mass, and systolic function were assessed by M-mode echocardiography and LV filling by Doppler velocimetry of transmitral flow. An audible S3 was detected in 22 subjects, 1 of whom had heart disease. The prevalence of physiological S3 was 23.1%. Subjects with physiological S3 had a lower body mass index (22.3 +/- 2.8 versus 24.6 +/- 4.1 kg/m2 [mean +/- SD], P = .005), lower heart rate (63 +/- 7 versus 68 +/- 10 beats per minute, P = .015), higher peak early diastolic transmitral velocity (67 +/- 10 versus 58 +/- 8 cm/s, P = .002), and higher acceleration of early diastolic velocity (717 +/- 148 versus 622 +/- 122 cm/s2, P = .012) than those without S3. No differences were noted in the lifestyle characteristics, blood pressure, or LV mass and systolic function. Body mass index and peak early diastolic transmitral velocity were independent predictors of physiological S3 in logistic regression analysis. CONCLUSIONS: Nearly one fourth of persons approaching their forties still have an audible physiological S3. The presence of S3 is predicted by leanness and a high early diastolic LV inflow velocity; the disappearance of S3 is unlikely to be secondary to increasing blood pressure and relative LV hypertrophy, as is widely presented, but reflects a more primary age-related alteration of LV early diastolic function.

Adult↗
PubMed1993

Non-invasive magnetocardiographic localization of ventricular pre-excitation in the Wolff-Parkinson-White syndrome using a realistic torso model.

This study was performed to evaluate the accuracy of magnetocardiography in non-invasive localization of the ventricular pre-excitation site in patients suffering from the Wolff-Parkinson-White (WPW) syndrome. Twelve WPW patients were studied, in whom the pre-excitation caused serious supraventricular arrhythmias refractory to drug therapy. Magnetocardiographic measurements were performed in a magnetically shielded room, and non-invasive localization was computed from preprocessed magnetic signals using a current dipole source in a realistically shaped digital torso. All patients underwent intra-operative multicatheter mapping and subsequent dissection of the accessory atrioventricular connection. The intra-operative localization results were marked on magnetic resonance images of the heart, where magnetocardiographic results were also superimposed to allow comparison. The average of the three-dimensional differences between the magnetocardiographic and the invasive results was 2.1 +/- 0.9 cm. In all cases, the computed localization result was in the same or adjacent anatomical region as the intra-operative result. The present results show that the magnetocardiographic method using a realistic torso model is capable of localizing pre-excitation sites with sufficient accuracy to provide extra information so that non-pharmacological therapeutic interventions can be applied.

Adult↗