Previous cytomegalovirus infection and risk of coronary thrombotic events after stent placement

Donor Graft Cytomegalovirus Serostatus and the Risk of Arterial and Venous Thrombotic Events in Seronegative Recipients After Non-Thoracic Solid Organ Transplantation

BACKGROUND

Cytomegalovirus (CMV) is the most common opportunistic pathogen, following solid organ transplantation (SOT), that leads to direct and indirect effects. The aim of this study was to assess the impact of CMV exposure at transplantation on the rate of posttransplant thrombotic events (TEs).

METHODS

We conducted a retrospective cohort study of patients transplanted at the University of Alberta Hospital between July 2005 and January 2018. We included adult SOT CMV-seronegative recipients at transplantation who received an allograft from either a seropositive donor (D+/R-) or a seronegative donor (D-/R-).

RESULTS

A total of 392 SOT recipients were included: 151 (39%) liver, 188 (48%) kidney, 45 (11%) pancreas, and 8 (2%) other transplants. The mean age was 47 years, 297 (76%) were males, and 181 (46%) had a CMV D+/R- donor. Patients in the CMV D+/R- cohort were slightly older (51 years versus 48 years in the D-/R- cohort; P = .036), while other variables, including cardiovascular risk factors and pretransplant TEs, were not different between groups. Overall, TEs occurred in 35 (19%) patients in the CMV D+/R- group, versus 21 (10%) in the CMV D-/R- group, at 5 years of follow-up (P = .008); the incidence rates per 100 transplant months were 5.12 and 1.02 in the CMV D+/R- and CMV D-/R- groups, respectively (P = .003). After adjusting for potential confounders with a Cox regression model, a CMV D+/R- transplantation was independently associated with an increased risk of a TE over 5 years (adjusted hazard ratio, 3.027; 95% confidence interval, 1.669-5.488).

CONCLUSIONS

A CMV D+/R- transplantation is associated with an increased risk of a TE posttransplantation.

Cytomegalovirus Infection in Cardiovascular Diseases

Atherosclerosis underlies the development of many cardiovascular diseases that continue to hold a leading place among the causes of death in developed countries. The role of activated immune cells in atherosclerosis progression has been convincingly demonstrated, but the mechanism of their action remains poorly investigated. Since atherosclerosis is associated with chronic inflammatory response, involvement of viral and bacterial infections in atherogenesis has been examined. A special place among the infectious agents is held by human herpesviruses as the most common persistent viruses in human population coupled to chronic inflammation during atherosclerosis. We found that activation of cytomegalovirus (CMV, human herpesvirus 5) infection is associated with the emergence of acute coronary syndrome, which is in a good agreement with the data on productive CMV infection published elsewhere. In this review, we discuss the data obtained by us and other researchers regarding the role of cytomegalovirus infection and related potential mechanisms resulting in the expansion of atherosclerotic plaques during ischemic heart disease and stroke, including virus transfer to immune and endothelial cells via extracellular vesicles. In particular, the data presented in the review demonstrate that virus spreading in the vascular wall triggers immune system activation in atherosclerotic plaques and causes endothelial dysfunction. Moreover, productive CMV infection in patients with acute myocardial infarction correlates with the extent of endothelial dysfunction. The mechanisms described by us and other researchers may explain the role of CMV infection in atherosclerosis and development of ischemic heart disease.

Myopericarditis complicated by pulmonary embolism in an immunocompetent patient with acute cytomegalovirus infection: a case report

Background

Primary acute cytomegalovirus infection in immunocompetent patients is common worldwide. Infection is most often asymptomatic or occurs sub-clinically with a self-limited mononucleosis-like syndrome. More rarely, the infection may lead to severe organ complications with pneumonia, myocarditis, pericarditis, colitis and hemolytic anemia. Recent cases of cytomegalovirus-associated thrombosis have also been reported sporadically in the medical literature.

Case presentation

We report here a case of simultaneous myopericarditis and pulmonary embolism in a 30-year-old man with no medical history. The patient was not immunocompromised. We discuss the possible role of acute cytomegalovirus infection in the induction of vascular damage and review relevant cases in the literature.

Conclusion

Thrombosis in patients with acute cytomegalovirus infection may be more frequent than is generally thought. Physicians need to be aware of the possible association between acute cytomegalovirus and thrombosis in immunocompetent patients, especially in the presence of severe systemic infection, as our case illustrates.

Association between cytomegalovirus infection and venous thromboembolism

It has been suggested that cytomegalovirus (CMV) infection may be associated with thrombosis in immunocompromised patients. In addition, an association between CMV infection and thrombotic events in immunocompetent hosts has been sporadically reported. We report on 1 immunocompromised and 8 immunocompetent adults who were admitted to a tertiary medical center and experienced a venous thromboembolic event during CMV infection. None reported previous thromboembolic events. All patients were diagnosed as suffering from acute CMV infection. Seven of the patients had vein thromboses. Significant additional thrombophilia was identified in 5 patients; 1 had 15.3 U/mL anti-cardiolipin IgM antibodies (elevated >7), 2 others were not evaluated for genetic procoagulant tendency. The exact nature of the procoagulant effect of CMV has not yet been clarified. Even though these mechanistic studies are incomplete, we suggest that from the clinical perspective, the presence of CMV infection should be considered a possible risk factor for thrombophilia, justifying a high index of suspicion for possible thrombotic events and subsequent decisions regarding prophylactic anticoagulation.

Cytomegalovirus colitis--an unusual cause for diarrhoea in an elderly woman

BACKGROUND

Clinically apparent cytomegalovirus (CMV) disease is uncommon in the immunocompetent host, despite the high seroprevalence rate of CMV in the general population.

CASE REPORT

Here, we report the case of CMV colitis in an immunocompetent elderly woman who developed a large pulmonary embolism during her illness.

DISCUSSION

The diagnosis of CMV colitis is made on histological examination of biopsy specimens obtained at sigmoidoscopy or colonoscopy. Extensive CMV disease can be accompanied by vascular thrombosis.

Cytomegalovirus-associated venous thromboembolism in renal transplant recipients: a report of 7 cases

Renal-transplant recipients have a higher prevalence of thromboembolic events compared with the general population. This elevated risk has been attributed to immunosuppressive drugs as well as metabolic and immunologic factors. Cytomegalovirus (CMV) infection, a frequent complication of transplantation, is known to modify endothelial phenotype from anticoagulant into procoagulant. There are few reports addressing the association of venous thromboembolism with CMV infection in immunocompetent patients. Some authors have also reported cases of arterial thrombosis in transplant recipients presenting CMV infection. However, the association of venous thromboembolic events with CMV infection has not yet been discussed in these patients. We present seven cases of simultaneous acute CMV infection and venous thromboembolism in renal-transplant recipients and suggest a potential causative effect.

Human cytomegalovirus causes endothelial injury through the ataxia telangiectasia mutant and p53 DNA damage signaling pathways

Atherosclerosis is the leading cause of death in the United States, and human cytomegalovirus (HCMV), a member of the herpes virus family, may play a role in the development of the disease. We previously showed that HCMV regulated endothelial apoptosis. In this study, we investigated the induction of apoptosis and signal transduction pathways regulating this process in HCMV-infected endothelial cells. As observed previously, HCMV induced a typical cytopathic effect in human aortic endothelial cells (HAECs), ie, the formation of single nucleated or multinucleated giant cells. Although infected HAECs were resistant to apoptosis at earlier stages of infection, they became apoptotic with prolonged infection as demonstrated by positive staining using terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL). This apoptotic process was mediated by the caspase-dependent mitochondrial apoptotic pathway as indicated by increased expression and cleavage of caspases 3 and 9 as well as increased expressions of pro-apoptotic molecules Bax and Bak. Blocking caspases 3 or 9 significantly inhibited the HCMV-induced apoptosis. Further exploration of the upstream pathway demonstrated upregulation of the tumor suppressor p53 gene and activation of the ataxia telangiectasia mutant (ATM) pathway in the infected cells. Blocking p53 inhibited HCMV-stimulated Bax and Bak expression as well as caspase-3 activation and blocking the ATM pathway inhibited HCMV-stimulated p53 activation. Although early infection may render cells antiapoptotic, prolonged infection, however, induced endothelial apoptosis through ATM and p53-dependent activation of the mitochondrial death pathway. This proapoptotic effect may be relevant to endothelial dysfunction and HCMV-associated vascular diseases.

Previous cytomegalovirus infection and restenosis after aggressive angioplasty with provisional stenting

The aim of this study was to determine the impact of previous with cytomegalovirus (CMV) on restenosis after aggressive angioplasty with provisional stenting.

DESIGN

We prospectively studied 78 consecutive patients scheduled for 6-month follow-up coronary angiography as part of the SIPS study. Anti-CMV IgG and IgM antibodies were measured on admission.

RESULTS

Anti-CMV IgG positive and anti-CMV IgG negative patients had similar minimal lumen diameter (MLD) in the target vessel before (0.68 +/- 0.49 mm vs 0.71 +/- 0.52 mm, P = 0.84) and directly after the intervention (2.50 +/- 0.60 mm vs 2.57 +/- 0.52 mm, P = 0.58). After 6 months, however, the MLD was significantly smaller in CMV-positive as compared to CMV-negative patients (1.57 +/- 0.82 mm vs 2.00 +/- 0.83 mm, P < 0.03). Net lumen gain at 6 months was significantly lower in CMV-positive patients (0.89 +/- 0.79 mm vs 1.30 +/- 0.87 mm, P < 0.04) and the rate of clinically relevant restenosis was significantly higher (31% vs 7%, P < 0.02). In a multivariate logistic regression model, CMV seropositivity was an independent predictor of restenosis (odds ratio 5.7 (95% CI 1.2-30.3, P = 0.04).

CONCLUSIONS

Six months after aggressive coronary angioplasty with provisional stenting, patients with prior CMV infection had a smaller MLD and a higher restenosis rate. CMV seropositivity was a strong independent predictor of restenosis.

Vascular thrombosis and acute cytomegalovirus infection in immunocompetent patients: report of 2 cases and literature review

Acute cytomegalovirus (CMV) infection in immunocompetent patients is common worldwide, with seroprevalence rates of 40%-100%, depending on the country, socioeconomic conditions, and the patient's age. Infection is most often asymptomatic, but acute cytomegalovirus infection is occasionally revealed by prolonged fever, cervical lymphadenitis, and arthralgia, and it is more rarely revealed by pneumonia, myocarditis, pericarditis, colitis, and hemolytic anemia. Here, we report 2 cases of acute CMV infection in nonimmunocompromised adults that were complicated by venous thrombosis with pulmonary embolism. We also review previously reported cases of vascular thrombosis and discuss the propensity of CMV to induce vascular damage with associated thrombosis.

Role of IgG-seropositivity to Chlamydia pneumoniae in early thrombotic events after coronary stent placement

AIMS

Since infection of endothelial or smooth muscle cells with Chlamydia pneumoniae increased expression of tissue factor and plasminogen activator inhibitor I (PAI-1), C. pneumoniae might be involved in triggering acute thrombotic events in patients with coronary artery disease. Therefore, we explored a potential relationship between IgG-seropositivity to C. pneumoniae and early thrombotic events after coronary stent placement.

METHODS AND RESULTS

In a prospective randomized placebo-controlled study 1010 patients with successful coronary stent placement received roxithromycin or placebo for 4 weeks after coronary stent placement, which showed no effect of roxithromycin on early thrombotic events, as expected. Venous blood samples were collected from patients immediately before treatment. Plasma was analyzed for C. pneumoniae-specific IgG antibody levels by microimmuno-fluorescence. Thrombotic events were defined as death, non-fatal myocardial infarction, or urgent target vessel reintervention within 30 days after stent placement. We found no significant difference concerning the frequency of early thrombotic events in patients positive or negative for C. pneumoniae-specific antibodies. If patients were stratified according to their antibody levels, again no significant difference in the frequency of thrombotic events was observed.

CONCLUSION

Our findings do not suggest a role of C. pneumoniae in the development of early complications after stent placement.

Thrombosis associated with cytomegalovirus infection in patients with ANCA-positive vasculitis

Three cases of venous thrombosis with pulmonary embolism in two patients associated with underlying antineutrophil cytoplasmic autoantibody (ANCA)-positive vasculitis and reactivated cytomegalovirus (CMV) infection are described. In vitro studies previously have shown that infection of endothelium with CMV increases the release of procoagulant factors and stimulates the expression of adhesion molecules. Because the endothelial cell plays a pivotal role in maintaining the equilibrium between procoagulant and anticoagulant states, injury by ANCA-positive vasculitis and additional infection with CMV may ignite a local thrombosis easily. Although venous thrombosis is uncommon in CMV infection (eg, in the immunosuppressed state after organ transplantation), the combination of vasculitis and reactivated CMV infection may have contributed to injury of the vessel wall with subsequent development of thrombosis. A better awareness of this association could improve morbidity and may lead to prevention of potentially life-threatening pulmonary embolism. Patients with ANCA-positive vasculitis and CMV infection may profit from prophylactic anticoagulant therapy with heparin or low-molecular-weight heparin.

Cytomegalovirus disease is not a major risk factor for ischemic heart disease after renal transplantation

BACKGROUND

It has been suggested that cytomegalovirus infection increases the risk of ischemic heart disease. Both cytomegalovirus and ischemic heart disease are common after renal transplantation, suggesting a possible causal association in this population.

METHODS AND PATIENTS

We studied 1004 consecutive renal transplants with no prior history of ischemic heart disease and grafts that functioned at least 12 months. We performed univariate and multivariate analyses to examine the effect of cytomegalovirus disease and other risk factors (measured during the first posttransplant year) on the development of primary ischemic heart disease events after the first posttransplant year.

RESULTS

More than 1 year after transplantation, 116 patients (11.6%) experienced their first ischemic event (75 myocardial infarction, 12 percutaneous angioplasty, 18 bypass grafting, and 11 deaths). Patients with ischemic heart disease were more likely to have known risk factors (age, diabetes, smoking, hypercholesterolemia, systolic blood pressure, low serum albumin, and acute rejections). However, the incidence of cytomegalovirus disease was not different for those with or without ischemic heart disease (36.2% vs. 31.1%). Moreover, a similar proportion of those with and without ischemic heart disease (19.8% vs. 15.5%) had a rise in cytomegalovirus antibodies during follow-up. By multivariate analysis, risk factors for ischemic heart disease (P<0.05) were age, diabetes, smoking, low serum albumin, and two or more acute rejections during the first year. Cytomegalovirus disease was not associated with ischemic heart disease events: unadjusted relative risk=1.14 (95% confidence interval 0.78-1.67, P=0.485). After adjusting for multiple risk factors, the relative risk was 0.91 (0.60-1.37, P=0.657).

CONCLUSION

These data suggest that cytomegalovirus disease is not a significant risk factor for the development of primary ischemic heart disease after renal transplantation.

Chlamydia pneumoniae and luminal narrowing after coronary angioplasty

OBJECTIVES

Numerous studies have linked Chlamydia pneumoniae with atherosclerotic vessel disease and a trend for an association of the bacteria with restenosis after percutaneous transluminal coronary angioplasty (PTCA) has also been observed. The aim of this study was to assess the role of Chlamydia pneumoniae in the luminal narrowing taking place after PTCA.

DESIGN

A noninterventional 6-month follow-up study.

SETTING

A university hospital.

SUBJECTS

A total of 122 patients with angiographically proven coronary heart disease (CHD) referred for PTCA.

INTERVENTIONS

None.

MAIN OUTCOME MEASURES

The degree of luminal narrowing in the coronary arteries following coronary angioplasty.

RESULTS

The levels of C. pneumoniae antibodies (IgG, IgA and IgM classes) and immune complexes were not associated with luminal narrowing after PTCA in multivariate analyses whilst smoking, plasma endothelin levels and diabetes were. The serologic parameters did not change during the follow up either.

CONCLUSIONS

These results do not support a role for C. pneumoniae in luminal narrowing following PTCA.

Preprocedural C-reactive protein levels and cardiovascular events after coronary stent implantation

OBJECTIVES

This study assessed the predictive value of preprocedural C-reactive protein (CRP) levels on six-month clinical and angiographic outcome in patients undergoing coronary stent implantation.

BACKGROUND

Recent data indicate that low-grade inflammation as detected by elevated CRP serum levels predicts the risk of recurrent coronary events.

METHODS

We prospectively investigated the predictive value of preprocedural CRP-levels on restenosis and six-month clinical outcome in 276 patients after coronary stent implantation. The primary combined end point was death due to cardiac causes, myocardial infarction related to the target vessel and repeat intervention of the stented vessel.

RESULTS

Grouping patients into tertiles according to preprocedural CRP-levels revealed that, despite identical angiographic and clinical characteristics at baseline and after stent implantation, a primary end point event occurred in 24 (26%) patients of the lowest tertile, in 42 (45.6%) of the middle tertile and in 38 (41.3%) of the highest CRP tertile, p = 0.01. On multivariate analysis, tertiles of CRP levels were independently associated with a higher risk of adverse coronary events (relative risk = 2.0 [1.1 to 3.5], tertile I vs. II and III, p = 0.01) in addition to the minimal lumen diameter after stent (p = 0.04). In addition, restenosis rates were significantly higher in the two upper tertiles compared with CRP levels in the lowest tertile (45.5% vs. 38.3% vs. 18.5%, respectively, p = 0.002).

CONCLUSIONS

Low-grade inflammation as evidenced by elevated preprocedural serum CRP-levels is an independent predictor of adverse outcome after coronary stent implantation, suggesting that a systemically detectable inflammatory activity is associated with proliferative responses within successfully implanted stents.

Circulating nucleic acids of Chlamydia pneumoniae and cytomegalovirus in patients undergoing coronary angiography

Peripheral blood mononuclear cells from 208 consecutive patients undergoing elective coronary angiography or angioplasty were collected before, immediately after, and 4 h after the procedure. Nucleic acids of Chlamydia pneumoniae and of cytomegalovirus (CMV) were detected by PCR and confirmed by hybridization. Circulating C. pneumoniae DNA was identified in 24 patients (11.5%) and was associated with current smoking (odds ratio [OR] = 4.5, 95% confidence interval [CI] = 1.6 to 12.2, P = 0.004) but not with arterial narrowing on coronary angiogram or with serological results positive for C. pneumoniae. Circulating CMV DNA was identified in 36 patients (17.3%) and was associated with anti-CMV immunoglobulin G (OR = 2.7, 95% CI = 1.2 to 6.3, P = 0.02) but not with angiographic arterial narrowing or with the need for revascularization. Neither C. pneumoniae nor CMV DNA detection increased after angioplasty, a procedure in which endothelium is disrupted. Larger prospective studies are needed to determine the prognostic significance of DNA detection.