Jukka Juvonen

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.

Demonstration of Chlamydia pneumoniae in the walls of abdominal aortic aneurysms

BACKGROUND Seroepidemiologic studies have indicated an association between chronic Chlamydia pneumoniae infection and coronary heart disease. The organism, which is a common respiratory pathogen, has been demonstrated in atherosclerotic lesions of the aorta and coronary arteries. Abdominal aortic aneurysms are frequently associated with atherosclerosis, and inflammation may actually be an important factor in aneurysmal dilatation. Hence it could be assumed that C. pneumoniae may play a role in maintaining an inflammation and triggering the development of aortic aneurysms. METHODS AND RESULTS Specimens from abdominal aortic aneurysm were examined for the presence of C. pneumoniae by immunohistochemical analysis, the polymerase chain reaction amplifying omp 1 gene, transmission electron microscopy, and culture methods with histologically atherosclerosis-negative human aortic tissues used as a control group. Chlamydial lipopolysaccharide and C. pneumoniae specific antigens were found by immunohistochemistry in 12 and 8 of 12 aneurysm specimens, respectively, and C. pneumoniae DNA could be demonstrated in 6 of 6 aneurysm specimens studied. Furthermore electron microscopy revealed the presence of Chlamydia-like elementary bodies in three of four aneurysm specimens tested. None of the control samples gave positive reaction in the polymerase chain reaction, and C. pneumoniae antigens were not detected in any of them. CONCLUSIONS C. pneumoniae is frequently found in the vessel wall of abdominal aortic aneurysm. The potential etiopathogenetic role of C. pneumoniae in the development of these aneurysms remains to be studied.

Detection of Chlamydia pneumoniae–Reactive T Lymphocytes in Human Atherosclerotic Plaques of Carotid Artery

Linkage between Chlamydia pneumoniae infection and atherosclerosis has been confirmed in several studies, but the precise role of this organism in the disease process is not known. We investigated the relation and reactivity of T lymphocytes of human carotid plaques to C pneumoniae antigens. Tissue specimens were obtained from 17 patients who underwent carotid endarterectomy. Immunohistological staining and/or in situ hybridization revealed the presence of C pneumoniae in 11 (64%) of the 17 of the cases. Inflammatory infiltration seen in the vessel walls consisted primarily of CD45RO+ T-memory lymphocytes (median 80%, range 50% to 90%), whereas CD20+ B cells and monocytes were in minor proportion. In vivo activated T lymphocytes were propagated from the specimens with interleukin-2, and the antigen specificity of the established T-cell lines (TLLs) was analyzed against C pneumoniae elementary body antigen. TLLs were established from all 17 carotid tissues but none from the control specimens of ascending aorta. C pneumoniae was recognized as a specific T-cell-stimulating antigen in 7 (41%) of 17 cases. Further analyses of the C pneumoniae-reactive TLLs showed that chlamydial 60-kDa heat-shock protein induced specific proliferation in 5 (71%) of 7 cases and revealed 2 haplotype (DRB1*1502 and DQB1*06) binding motifs in human 60-kDa heat-shock protein. C pneumoniae was identified as a specific microbial antigen recognized by 41% of TLLs propagated from in vivo activated plaque T cells. Our results suggests that cell-mediated immunity to C pneumoniae plays a role in the atherosclerotic process and that this response may involve autoimmunity.

Coronary angioplasty in drug eluting stent era for the treatment of unprotected left main stenosis compared to coronary artery bypass grafting

Background. Improved outcomes of percutaneous coronary interventions (PCI) with drug-eluting stents (DES) have resulted in their expanded use for left main coronary artery (LMCA) stenosis. Aim. We compared outcomes of patients undergoing PCI for unprotected LMCA stenosis and patients treated by coronary artery bypass grafting (CABG). Method. Between January 2005 and January 2007, 6705 patients were studied with coronary angiography in northern Finland. All subjects treated with revascularization of LMCA stenosis (n=287) were included and followed up for a mean of 12±6 months. Results. From 287 patients, 238 underwent CABG, and 49 had PCI with DES. The incidence of 1-year mortality was 4% among the PCI-treated and 11% among CABG-treated patients (P=0.136). After the first month, mortality among PCI- or CABG-treated patients did not differ statistically significantly (2% versus 7%, P=0.133). The most significant independent predictor of mortality was reduced left ventricular systolic function (hazard ratio 14.9, 95% CI 5.5–40.0, P<0.001). Conclusions. PCI with DES for selected LMCA disease patients results in short- and midterm outcomes comparable to results of CABG in general. PCI is a viable therapeutic option in selected patients with LMCA stenosis.

Effectiveness of amiodarone as a single oral dose for recent-onset atrial fibrillation

The efficacy of amiodarone has been proved in long-term maintenance of sinus rhythm (SR) in patients with paroxysmal atrial fibrillation (AF). The present study evaluates the efficacy and safety of a single oral dose of amiodarone in patients with recent-onset AF (<48 hours). Seventy-two patients were randomized to receive 30 mg/kg of either amiodarone or placebo. Conversion to SR was verified by 24-hour Holter monitoring. Ten patients were excluded because of SR in the beginning of monitoring or technical failure during Holter monitoring. The remaining study groups were comparable (n = 31 for each), except that in the placebo group beta blockers were more common. The patients receiving amiodarone converted to SR more effectively than those receiving placebo (p<0.0001). At 8 hours, approximately 50% of patients in the amiodarone group and 20% in the placebo group (Holter successful) had converted to SR, whereas after 24 hours the corresponding figures were 87% and 35%, respectively. The median time for conversion (8.7 hours for amiodarone and 7.9 hours for placebo) did not differ in the groups. Amiodarone was hemodynamically well tolerated, and the number of adverse events in the study groups was similar. Amiodarone as a single oral dose of 30 mg/kg appears to be effective and safe in patients with recent-onset AF.

Can degenerative aortic valve stenosis be related to persistent Chlamydia pneumoniae infection

Aortic valve stenosis can be categorized into three groups: rheumatic, bicuspid, and degenerative [1]. Because of the increasing age of the general population, degenerative (tricuspid) aortic valve calcification constitutes a substantial health problem [2, 3]. Its cause is largely unknown, but one typical characteristic is an active inflammatory process that bears some similarities to atherosclerosis [4, 5]. Chlamydia pneumoniae is a common cause of respiratory infections worldwide [6, 7]. Epidemiologic studies have indicated an association between atherosclerosis and C. pneumoniae infection, and this pathogen has been found in atherosclerotic lesions [8-12]. In addition, all Chlamydia species have been observed to cause heart infections [13, 14]. Chlamydia pneumoniae is frequently found in stenotic aortic valves and in the early lesions associated with this disease, but it is rarely found in normal aortic valves of age-matched controls [15]. Chlamydia pneumoniae may merely be an innocent bystander occupying damaged tissues; however, because this organism is known to cause persistent infections, it may trigger and maintain the chronic inflammation found in aortic stenosis. We explored the association between C. pneumoniae infection and aortic stenosis. We tested the hypothesis that if persistent C. pneumoniae infection plays an active role in the development of aortic stenosis, the organism can be detected in the healthy aortic valves of young persons. Methods Patients Aortic valves were obtained from 46 consecutive cadavers undergoing autopsy at the Departments of Forensic Medicine and Pathology at Oulu University Hospital and University of Oulu, Oulu, Finland. The ascending aorta was incised longitudinally, the aortic valve was exposed, and the leaflet movements were evaluated. The valve and its annulus were excised. In accordance with previous studies [4, 15], macroscopic disease was classified as absent (translucent, flexible leaflets with no opaque area), as a mild or early lesion (opaque leaflets with focal areas of thickening and increased stiffness but no obstruction), or as severe (definite areas of calcification and thickening with substantial obstruction). The macroscopic analyses were performed by two of the authors, who were blinded to other aspects of the investigation. The ethical committee of Oulu University approved the study. Immunohistochemistry The noncoronary leaflets of the valves were immersed in 10% buffered formalin for at least 24 hours and were embedded in paraffin for immunohistochemical and histologic studies, which were performed in a blinded manner. For immunohistochemical studies, 4-m to 5-m slices were cut, deparaffinized, rehydrated, and digested with pepsin. No other antigen retrieval methods were used. Slices were then treated with H (2) O2 to remove peroxidase activity and with normal serum to remove nonspecific binding of the antibody. The specimens were incubated with C. pneumoniae monoclonal antibody RR402 (Washington Research Foundation, Seattle, Washington) in 1:200 dilution for 1 hour at room temperature and were washed carefully. Binded antibody was detected by using the avidin-biotin-peroxidase method of Hsu and colleagues [16] with a Vestastain ABC kit (Vector Laboratories, Burlinggame, California). Diaminobenzidine was used as substrate. HL cells infected with C. pneumoniae were used as positive controls, and normal aorta and myometrium were used as negative controls. Only granular intracellular staining was accepted as positive. Statistical Analysis To study the possible persistence of C. pneumoniae in aortic valves, the data were stratified by age (persons 20 to 40 years of age [n = 15], persons 41 to 60 years of age [n = 16], and persons older than 60 years of age [n = 15]). The two-sided Fisher exact test was used to determine whether probability of early lesion was related to the presence of C. pneumoniae in the aortic valve. A P value less than 0.05 was considered significant. We calculated 95% CIs for differences in proportions by using the exact method in StatXact3 for Windows (Cytel Software Corp., Cambridge, Massachusetts). Results The mean age at death was 50 years (range, 22 to 83 years). Thirty persons were men and 16 were women. All of the aortic valves were tricuspid, and none was stenotic. Thirty-four of the 46 valves were macroscopically normal. Early lesions were detected in 12 valves (0 of 15 valves from persons 20 to 40 years of age, 4 of 16 valves from persons 41 to 60 years of age, and 8 of 15 valves from persons older than 60 years of age; P = 0.004). In one case, mild aortic insufficiency was recorded at autopsy. Histologic examination of the 12 valves with early lesions showed degeneration, calcification, and variable inflammatory cell infiltrates. Some of the macroscopically normal valves had degenerative changes on microscopic analysis. Positivity for C. pneumoniae was seen in stromal spindle and mononuclear cells and was spread diffusely in the valve tissue. In normal valves, scattered macrophages but no T cells were detected. Valves with early lesion were characterized by the presence of an inflammatory infiltrate composed of macrophages and occasional T cells. A positive result on staining was not clearly associated with inflammatory reactions, although both inflammation and positivity for C. pneumoniae increased with age and were more frequently found in valves with early lesions. Macroscopically and microscopically normal valves without inflammation tested positive for C. pneumoniae. A typical positive immunostaining is shown in the (Figure 1). Twenty-five valves (54%) had positive results on staining (15 of 34 macroscopically normal aortic valves [44%] and 10 of 12 valves with early lesions [83%]; P = 0.02). The relations of age and result of staining for C. pneumoniae to the presence of early lesions are shown in the (Table 1). Nine of 15 valves (60%) from persons 20 to 40 years of age, 8 of 16 valves (50%) from persons 41 to 60 years of age, and 8 of 15 valves (53%) from persons older than 60 years of age had a positive result on staining. No person younger than 40 years of age had early lesions, and the chance of early lesions in persons 41 to 60 years of age tended to be greater if C. pneumoniae was present in the aortic valve (3 of 4 [75%] aortic valves with C. pneumoniae infection compared with 5 of 12 [42%] aortic valves without C. pneumoniae infection; P > 0.2). Persons older than 60 years of age had a significantly greater chance of early lesion if they had C. pneumoniae infection (7 of 8 [87%] aortic valves with C. pneumoniae infection compared with 1 of 7 [14%] valves without C. pneumoniae infection; P = 0.01). Among macroscopically normal valves, 9 of 15 (60%) from persons 20 to 40 years of age, 5 of 12 (42%) from persons 41 to 60 years of age, and 1 of 7 (14%) from persons older than 60 years of age had positive results on staining. Figure 1. A positive result on immunohistochemical staining with Chlamydia pneumoniae species specific antibody in mononuclear cells (arrows) of a macroscopically normal aortic valve. Table 1. Relation of Age and Chlamydia pneumoniae Immunostaining to Early Lesions of Aortic Valve Stenosis in 46 Consecutive Cadavers Discussion Our results show that C. pneumoniae is frequently found in the aortic valves of adults of different ages and that the presence of this pathogen is associated with aortic valve disease in elderly persons. This finding suggests the persistence of C. pneumoniae in normal aortic valve tissue. The persistence of Chlamydia species is a well-known phenomenon [17-19]. It has long been known that C. trachomatis can be detected by immunofluorescence in the eyes of many persons who do not have any signs of active disease [17-20], and the persistence of C. pneumoniae in throat swab specimens has been shown [20]. Our findings show that C. pneumoniae can infect the normal aortic valve and that infection may persist. The 50% rate of positivity for C. pneumoniae in aortic valves is in line with the overall prevalence of the antibody. Chlamydia pneumoniae infection is very common in children, and the prevalence of antibodies indicating past infection is about 50% in young adults. In older age groups, the prevalence of antibodies increases to as much as 75% [2]. The antibody response is limited to 3 to 5 years; this suggests that most people become infected several times during their lives. Chlamydia pneumoniae has been found in atherosclerotic lesions and stenotic aortic valves, but it has not been found in normal vessel walls or in the occluded coronary arteries of patients in whom transplants are chronically rejected [5-7]. This has raised the question of whether C. pneumoniae infects only atherosclerotic vessels or is an innocent bystander. Most of the C. pneumoniae-positive valves in our study were macroscopically normal, but C. pneumoniae was rarely found in normal valves in elderly persons (as observed in our previous study [15]). The finding that C. pneumoniae transfers from normal valves to valves with early lesions over the years suggests the pathologic potential of the organism. The difference between the incidence of C. pneumoniae in normal valves and valves with early lesions supports a possible causal relation. What could be the role of latent chlamydial infection in the pathogenesis of degenerative aortic stenosis? Of interest, a chlamydial antigen was reported to be present in aortic stenosis in 1974 [14]. In those patients, the diagnosis was based on results of an indirect immunofluorescence test that used polyclonal anti-C. psittaci antibodies, which probably contained genus-specific antibodies that reacted not only with C. psittaci but also with C. pneumoniae and C. trachomatis [13]. There is little evidence of the clinical significance of persistent chlamydial infections. The host response to the infection seems to be a major contributor to the development of the d

Two founder mutations in the alpha-tropomyosin and the cardiac myosin-binding protein C genes are common causes of hypertrophic cardiomyopathy in the Finnish population

Background. Hypertrophic cardiomyopathy (HCM) is predominantly caused by a large number of various mutations in the genes encoding sarcomeric proteins. However, two prevalent founder mutations for HCM in the alpha-tropomyosin (TPM1-D175N) and myosin-binding protein C (MYBPC3-Q1061X) genes have previously been identified in eastern Finland. Objective. To assess the prevalence of these founder mutations in a large population of patients with HCM from all over Finland. Patients and methods. We screened for two founder mutations (TPM1-D175N and MYBPC3-Q1061X) in 306 unrelated Finnish patients with HCM from the regions covering a population of ∼4,000,000. Results. The TPM1-D175N mutation was found in 20 patients (6.5%) and the MYBPC3-Q1061X in 35 patients (11.4%). Altogether, the two mutations accounted for 17.9% of the HCM cases. In addition, 61 and 59 relatives of the probands were found to be carriers of TPM1-D175N and MYBPC3-Q1061X, respectively. The mutations showed regional clustering. TPM1-D175N was prevalent in central and western Finland, and MYBPC3-Q1061X in central and eastern Finland. Conclusion. The TPM1-D175N and MYBPC3-Q1061X mutations account for a substantial part of all HCM cases in the Finnish population, indicating that routine genetic screening of these mutations is warranted in Finnish patients with HCM.

IS VASCULITIS A SIGNIFICANT COMPONENT OF ATHEROSCLEROSIS

Although atherosclerosis was linked to infections many decades ago, only recently there has been a renewed interest to study this association further. These research endeavors have provided a substantial amount of knowledge concerning the mechanisms that may link inflammation, immunity, and infections to the molecular and cellular events in the arterial wall leading to atherosclerotic lesions.

Long-term outcome after mitral valve repair

Background. Several studies reported excellent long-term results after mitral valve repair for regurgitation, however a number of patients still experience recurrent mitral valve regurgitation which requires reoperation. We have evaluated the long-term outcome of a consecutive series of patients who underwent mitral valve repair for regurgitation in an attempt to identify the risk factors associated with late failures. Patients and methods. One-hundred and sixty-four patients underwent mitral valve repair for ischemic and degenerative mitral valve regurgitation. Seventy-two patients underwent echocardiographic evaluation a median of 5.6 years after surgery. Results. Ten-year survival freedom from any fatal cardiac event was 75.9% and survival freedom from redo mitral valve surgery was 93.8%. Multivariable analysis showed that residual mitral valve regurgitation grade > 1 as assessed during the immediate postoperative period (at 10-year, 60.6% vs. 95.7%, p = 0.001, RR 20.7, 95%C.I. 3.4–125.3) and chronic obstructive pulmonary disease/asthma (at 10-year 66.8% vs. 95.2%, p = 0.013, RR 12.0, 95%C.I. 1.7–85.2) were predictors of redo mitral valve surgery. The same findings were observed also among patients with myxomatous degenerative disease. At echocardiographic follow-up, no significant improvement was detected in terms of left ventricular ejection fraction, whilst mitral valve regurgitation grade (median, 3 to 1), New York Heart Association class (median, 2 to 1) and left atrium diameter (median, 50 to 44 mm) decreased significantly. Conclusions. This study confirms the excellent clinical long-term results after mitral valve repair. An adequate repair technique is advocated in order to decrease the immediate postoperative rate of residual regurgitation > 1 as this is a main determinant of late failures requiring redo mitral valve surgery. Further studies are required to better define the possible causative role of chronic obstructive pulmonary disease and any underlying connective tissue metabolic disorder in late failures after mitral valve repair.

Mediastinal window: A cause of simultaneous bilateral spontaneous pneumothorax

A case of bilateral spontaneous pneumothorax with critical collapse of both lungs in a previously healthy 19-year-old woman is described. A congenital defect of mediastinal septum was suspected on the basis of roentgenographic findings and confirmed by right-sided thoracotomy. This mediastinal window between the pleural spaces allowed air leaking from a ruptured right lung apical bulla to collapse not only the right lung but also the left. Apical TA stapler resection and right-sided parietal pleurectomy was performed to prevent recurrence.