Immunologic and virologic studies in the postpericardiotomy syndrome

Postpericardiotomy syndrome after cardiac surgery

Postpericardiotomy syndrome (PPS) is a well-known complication after cardiac surgery. The syndrome results in prolonged hospital stay, readmissions, and invasive interventions. Previous studies have reported inconsistent results concerning the incidence and risk factors for PPS due to the differences in the applied diagnostic criteria, study designs, patient populations, and procedure types. In recent prospective studies the reported incidences have been between 21 and 29% in adult cardiac surgery patients. However, it has been stated that most of the included diagnoses in the aforementioned studies would be clinically irrelevant. This challenges the specificity and usability of the currently recommended diagnostic criteria for PPS. Moreover, recent evidence suggests that PPS requiring invasive intervention such as the evacuation of pleural and/or pericardial effusion is associated with increased mortality. In the present review, we summarise the existing literature concerning the incidence, clinical features, diagnostic criteria, risk factors, management, and prognosis of PPS. We also propose novel approaches regarding to the definition and diagnosis of PPS. Key messages: Current diagnostic criteria of PPS should be reconsidered, and the analyses should be divided into subgroups according to the severity of the syndrome to achieve more clinically applicable and meaningful results in the future studies. In contrast with the previous presumption, severe PPS - defined as PPS requiring invasive interventions - was recently found to be associated with higher all-cause mortality during the first two years after cardiac surgery. The association with an increased mortality supports the use of relatively aggressive prophylactic methods to prevent PPS. The risk factors clearly increasing the occurrence of PPS are younger age, pleural incision, and valve and ascending aortic procedures when compared to CABG.

The effect of short-term prophylactic acetylsalicylic acid on the incidence of postpericardiotomy syndrome after surgical closure of atrial septal defects

Postpericardiotomy syndrome (PPS), a potential complication of open heart surgery, has a variable clinical course and severity. This study evaluated the effectiveness of acetylsalicylic acid (ASA) prophylaxis in preventing PPS after surgical closure of atrial septal defects (ASDs) in pediatric patients. A retrospective review was performed for 177 patients who underwent uncomplicated ASD closure from 1986 to 2006. The study group received prophylactic ASA 20 to 50 mg/kg/day for 1 to 6 weeks after surgery, whereas the control group did not. The primary outcome was a diagnosis of PPS based on the presence of two or more of the following symptoms or signs occurring at least 72 h postoperatively: fever (temperature >38 degrees C), pericardial or pleural rub, and worsening or recurring anterior pleuritic chest pain. Consequently, PPS developed in 5 (2.8%) of the 177 children: 2.8% (3/106) in the control group and 2.8% (2/71) in the study group (p = 1.00). The secondary outcomes were frequency of other postoperative complications. Postoperative pericardial effusions experienced by 26.7% of the patients were identified more frequently in the treatment group (p < 0.001). Postoperative prophylaxis ASA at a dose of 20 to 50 mg/kg/day for 1 to 6 weeks after surgical closure of ASD does not decrease the incidence of PPS in pediatric patients.

The Spectrum of Pleural Effusions After Coronary Artery Bypass Grafting Surgery

Pleural effusions are common after coronary artery bypass grafting (CABG) surgery and can be categorized by time intervals: perioperative (within the first week), early (within 1 month), late (2-12 months), or persistent (after 6 months). The perioperative effusions are usually attributable to diaphragm dysfunction or internal mammary artery harvesting and are typically self-limited. Early effusions are usually attributable to postcardiac injury syndrome and may require corticosteroid treatment. Although late effusions can have multiple causes, persistent effusions are attributable to trapped lung and often require decortication. Diagnostic thoracentesis should be performed for patients with large symptomatic pleural effusions or fever after CABG surgery. The range of management includes observation, therapeutic thoracentesis, corticosteroids, or decortication depending on the cause and course of the effusion.

Postpericardiotomy syndrome: no evidence for a viral etiology

BACKGROUND

Postpericardiotomy syndrome has been considered a disorder induced by viral infection. This conclusion is based on serologic criterions, but these may be unreliable following either cardiopulmonary bypass or transfusion therapy. Previous studies have not verified the proposed etiology either by isolation of viruses, or by detection of their genome. We sought, therefore, to clarify the role, if any, of viruses in this syndrome.

METHODS AND RESULTS

We studied prospectively 149 children aged from 6 months to 16 years who were undergoing open heart surgery. Blood samples were collected from all prior to operation, and again 7 to 10 days post-operatively, and 47 were sampled at the time of development of symptoms of pericardial involvement. Serums were analyzed for the presence of IgM and IgG antibodies to cytomegalovirus, herpes simplex virus, and Epstein-Barr virus. The polymerase chain reaction was used for amplification when assessing the genome of the enteroviruses. Cultures for viruses were established on samples of stool, urine, and throat swabs collected 7 days post-operatively, and at the time of postpericardial symptoms. Pericardial fluid obtained from 5 patients with the syndrome was cultured for viruses, and tested for enterovirus genome. On the basis of clinical and echocardiographic findings, 34 children were determined to have definite evidence of the syndrome, 13 were considered to have possible evidence, and the results from these patients were compared to those from patients with no pericardial symptoms, the latter being matched for age and transfusion status. We isolated viruses from one or more sites in five patients with definite evidence (16%), from one (9%) of those with possible evidence, and from seven (19%) of the controls. All serums and pericardial samples were negative for enterovirus genome. IgM antibodies were found in only 5 patients, three with symptoms of pericardial involvement and two without. Rates of seroconversion to IgG for the viruses were lower in the patients with symptoms of pericardial involvement compared to controls, but were strongly influenced by transfusion status.

CONCLUSION

Our study has provided no evidence to support a viral etiology for the postpericardiotomy syndrome.

Intermediate follow-up of right ventricular outflow tract reconstruction with allograft conduits

BACKGROUND

Allograft conduits are among many varieties of material used for right ventricular outflow tract reconstruction. They invariably need to be replaced due to growth of the patient or conduit failure.

METHODS

From June 1984 to June 1996, a total of 76 patients underwent reconstruction of the right ventricular outflow tract with an allograft conduit: 51 aortic and 25 pulmonary. The median age, weight and conduit size at surgery were 37 months (range, 0.2 to 228 months), 12.4 kg (range, 2.9 to 61.4 kg), and 17 mm (range, 8 to 26 mm), respectively.

RESULTS

The hospital mortality was 5.3% (4 of 76 patients) and 2 patients died at 9 and 78 months follow-up. The median follow-up was 61 months (range, 2 to 132 months). Reoperation was necessary in 22 patients (28.9%) at a median interval of 50.5 months (range, 3 to 109 months) and the median conduit size was 21 mm (range, 12 to 23 months). There was no mortality. Freedom from reoperation at 64 months was 49.5% for conduits 15 mm and smaller, and 73.3% for conduits 16 mm and larger. Analysis by age shows freedom from reoperation at 64 months of 49.4% and 74.5% for patients younger than and older than 2 years, respectively. At 54 months there was no statistical difference in freedom from reoperation between pulmonary and aortic allografts.

CONCLUSION

Right ventricular outflow tract reconstruction with allograft conduits results in a high reoperation rate at 4 years but provides significantly longer freedom from reoperation with conduits larger than 15 mm or in patients over 24 months of age.

Evidence of endothelial dysfunction of epicardial coronary arteries in patients with immunohistochemically proven myocarditis

BACKGROUND

Recent reports indicate that myocarditis can be associated with acute myocardial ischemia and even myocardial infarction in patients with normal arteriograms. We therefore tested the hypothesis that patients with biopsy-proven myocarditis have endothelial dysfunction despite angiographically smooth epicardial coronary arteries.

METHODS AND RESULTS

Graded concentrations of the endothelium-dependent vasodilator acetylcholine (10(-6) to 10(-4) mol/L) and for comparison, the non-endothelium-dependent vasodilator nitroglycerin (0.3 mg intracoronary), were infused into the left coronary arteries of 18 patients (mean age 47+/-9 years, 8 women and 10 men) with biopsy-proven myocarditis but without angiographically demonstrable coronary artery disease. Vascular responses were analyzed by quantitative coronary angiography. Three patients had an intact vasodilator response to acetylcholine concentrations of up to 10(-4) mol/L in all segments of the left coronary artery, with a mean dilatation of +9.9%+/-2%. In contrast, paradoxical constriction by acetylcholine occurred in 9 patients, who showed a mean change in coronary artery diameter of - 11%+/-3%. Six patients had no significant change in any segments in response to acetylcholine (-2.5%+/-4%). There was a significant inverse correlation between the number of T-lymphocytes in the myocardium and the response of the epicardial coronary arteries to acetylcholine (Pearson correlation coefficient -0.49, P=.03).

CONCLUSIONS

It can be assumed that the process of myocarditis is associated with impairment of endothelium-dependent vasodilation in response to acetylcholine in most patients. Vasoconstriction in the presence of acetylcholine in myocarditis is likely to reflect an abnormality of endothelial function. Endothelial dysfunction of coronary arteries may explain the occurrence of myocardial ischemia in patients with myocarditis.

Postcardiac injury syndrome. An immunologic pleural fluid analysis

The postcardiac injury syndrome (PCIS) is characterized by inflammation of the pericardium, pleura, and pulmonary parenchyma following a variety of cardiac injuries. Although it has been clinically recognized for decades, confirmation of the syndrome has been problematic owing to lack of a sufficiently diagnostic test. Previously, we have reported pleural fluid characteristics which help to exclude other diagnoses that may mimic the syndrome. We describe the first immunologic assessment, including antimyocardial antibody testing, of pleural fluid from a patient with PCIS which supports a local immunologic mechanism in the pathogenesis of the syndrome. These results support the important role of pleural fluid analysis in the diagnosis of PCIS.

Autoantibody production after cardiopulmonary bypass with special reference to postpericardiotomy syndrome

A prospective study of children undergoing open heart surgery with cardiopulmonary bypass showed that many of them produced autoantibodies. No association was found between these antibodies, including anticardiolipin antibodies, and the occurrence of postpericardiotomy syndrome.

Cardiac issues in the pediatric emergency room

A great variety of problems referable to the cardiovascular system can prompt a visit to the pediatric emergency room. From the initial presentation of congenital heart disease, to the subsequent life-long management of these patients, to miscellaneous problems like Kawasaki disease and chest pain, the front-line pediatrician must be skilled in the recognition and early management of myriad complaints. This article focuses on information that can assist the emergency pediatrician in the evaluation and treatment of the cardiac patient from arrival in the emergency room until transfer of care to the pediatric cardiologist or inpatient staff.

The epidemiology of the postpericardiotomy syndrome: a common complication of cardiac surgery

PPS is a major cause of morbidity after cardiac surgery and may cause bypass graft closure and fatal cardiac tamponade. Little is known about its incidence and cause. To better define this syndrome characterized by postoperative fever, pericardial friction rub, and pericardial pain, we used two out of three of the preceding criteria to diagnose PPS. In a prospective epidemiologic study we followed 944 consecutive patients undergoing open-heart surgery between November 1984 and November 1985. The overall incidence was 17.8%. The incidence was increased in younger patients, in those with a history of prednisone use in the past, in patients with a past history of pericarditis, those with aortic valve replacement, and in patients who received enflurane or halothane anesthesia. PPS is a common syndrome. Knowledge of risk factors associated with PPS may allow its prevention and identification of patients who warrant early and aggressive treatment.

Rheumatic symptoms after cardiac surgery: a prospective study

The incidence of different types of shoulder pain after open heart surgery was studied prospectively. Of 101 patients studied, 45 developed rheumatic symptoms during the first six weeks after the operation. Thirty eight patients reported pain in the region of the shoulder girdle with no loss of shoulder function (postpericardiotomy rheumatism). Three of these patients also had features compatible with the postpericardiotomy syndrome (fever, malaise, or pleuritic chest pain), and seven developed the syndrome without pain in the shoulder girdle. Of these 10 patients, one had generalised myalgia. Postpericardiotomy rheumatism alone was not associated with increased inflammation (measured by the erythrocyte sedimentation rate and concentration of C reactive protein); immunological tests including measurement of antibodies to cardiac muscle yielded inconclusive results. Replies to a postal questionnaire showed that symptoms of postpericardiotomy rheumatism were present for over three months in 18 patients and for six months or longer in 14. In view of the large number of patients now having open heart surgery postpericardiotomy rheumatism should be considered when patients report pain around the shoulders so that it is not misdiagnosed as angina.

Infection and infarction. Acute viral (and other) infection in the onset, pathogenesis, and mimicry of acute myocardial infarction

Because a prospective controlled investigation showed a highly significant association of the onset of acute myocardial infarction with signs of preceding respiratory infection, the clinical, laboratory, experimental, and epidemiologic evidence more directly supporting this association was analyzed. Inflammation--specifically of infectious, usually viral, origin--has been shown by several lines of evidence to be capable of precipitating or mimicking clinical myocardial infarction. Myocardial biopsy is producing rapidly increasing confirmation that myocarditis can perfectly mimic clinical acute myocardial infarction. Coronary arteritis, with implications for vasospasm and thrombosis, is being increasingly demonstrated when deliberately sought in necropsy and biopsy material. Effects of blood-borne infectious agents, particularly viremia, on platelets in vivo and in vitro--aggregation and lysis with release of vasoactive substances--have even more serious potential for coronary thrombosis and vasospasm. It is not clear whether such mechanisms operate entirely independently or are more potent in high-risk patients, particularly in view of the demonstrable hypercoagulable state in many patients with coronary disease. Because of the great importance of confirming precipitating mechanisms for acute myocardial infarction (as well as its frequent mimic, myocarditis), intensive investigation of the relation between infection and infarction has important preventive and therapeutic implications.

Postpericardiotomy syndrome

Postpericardiotomy syndrome, a frequent complication of open-heart surgery, is characterized by fever, chest pain, and pericardial and pleural effusions. These signs may develop 1 to 12 weeks after intracardiac surgery in approximately 30 percent of patients. Although the etiology of the syndrome is unknown, evidence points to a viral and/or autoimmune cause. Postpericardiotomy syndrome is diagnosed after excluding other conditions such as endocarditis and pneumonia. In many cases, the syndrome is self-limiting and occurs only once, but in other cases the symptoms have recurred as many as eight times. When the symptoms recur, management is more difficult because optimal pharmacologic treatment is not known. Antiinflammatory agents, such as salicylates and steroids, represent the drugs most commonly used. Although analgesics with codeine or oxycodone are important for the patients' symptomatic relief, early recognition of the syndrome is the key to limiting the discomfort and possible complications associated with this condition.

Post-cardiac injury syndrome and an increased humoral immune response against the major contractile proteins (actin and myosin)

To better understand the pathogenesis of the post-cardiac injury syndrome (PCIS) 2 models of cardiac injury were studied. One hundred twenty-nine patients who underwent cardiac surgery and 80 patients with acute myocardial infarction (AMI) were prospectively followed and the levels of anti-heart antibodies (AHA), anti-actin antibodies (AAA) and anti-myosin antibodies (AMA) were determined. In the surgical group, PCIS developed in 27 patients (21%) and incomplete PCIS in 36 (28%). In the AMI group, PCIS did not develop in any patient, but incomplete PCIS developed in 11 patients (14%) (p less than 0.001). The surgical group showed a significantly higher humoral immune response than the AMI group when analyzed for AHA and anti-contractile protein antibodies. After cardiac surgery, AHA developed in 59 patients (46%), AAA developed in 33 (26%) and AMA developed in 49 (38%); in the AMI group, significant levels of AHA, AAA and AMA developed in 16 (20%), 7 (9%) and 13 patients (16%), respectively. These studies show a significant correlation between the PCIS clinical classification and auto-antibodies raised against heart contractile proteins.

Viral illness and the postpericardiotomy syndrome. A prospective study in children

Postoperative fever and pericardial-pleural reaction, designated postpericardiotomy syndrome (PPS), is a common complication of cardiac surgery involving entry into the pericardium. To determine whether the etiology of PPS is viral or immunologic, we undertook a prospective, triple-blind study of consecutive long-term survivors of intrapericardial surgery in the pediatric age group. We evaluated clinical evidence of syndrome and concurrent appearance of antiheart antibody (AHA) by indirect immunofluorescence and antiviral antibody (AVA) by complement fixation in sera preoperatively and serially postoperatively. Incidence of PPS was 27% overall in 400 subjects, but only 3.5% in infants younger than 2 years of age. AHA in high titer appeared in all patients with PPS. A fourfold or greater rise in titer to AVA was found in 70% of these but in only 5% of those with negative AHA and no PPS. AVA rise, tested in 280 consecutive patients, was to no single one of the eight viruses studied (adenovirus, cytomegalovirus, and coxsackievirus B 1-6). Instead, the rise and fall, consistent with antiviral response to a recent infection, was exhibited usually to one but occasionally to two or more viruses, and the viral prevalence changed from year to year, as did that in the community. The study suggests that concurrent fresh or reactivated viral illness plays a role in triggering the immunologic response that characterizes the PPS.

Gallium-67 citrate scanning for noninvasive detection of inflammation in pericardial diseases

The treatment of acute nonspecific pericarditis is controversial. No study is available that confirms the efficacy of the administration of corticosteroids or nonsteroid anti-inflammatory agents in this condition. There is no reliable invasive marker for pericardial inflammation, because echocardigraphy demonstrates only the presence of fluid. In four patients with pericarditis, gallium-67 citrate scanning was performed, and the isotope was localized to the cardiac silhouette in all. In one patient with effusion the gallium scan was positive and then reverted to negative with corticosteroid therapy. In another, the gallium scan remained positive despite resolution of the pericardial effusion with corticosteroid therapy. This patient eventually required pericardial stripping. Pericardial localization of gallium was useful in detecting the cause of fever in a patient after aortocoronary bypass grafting and in detecting pericardial involvement in a patient with multisystem viral disease. Pericardial localization of gallium-67 may be diagnostically useful and may provide a proper control for the study of the efficacy of corticosteroids versus nonsteroid anti-inflammatory agents in pericarditis.

The postpericardiotomy syndrome then and now

The postpericardiotomy syndrome is a febrile illness with pericardial and pleural reaction that either persists or appears beyond the 1st postoperative week. We believe that it begins in the 1st week after intrapericardial cardiac surgery, and that clinical signs of illness correlate with appearance of AHA and with significant rise in titer to AVA. Our present working hypothesis is that myocardial damage with bleeding into the pericardial sac at the time of surgery combines with concurrently acquired or reactivated viral illness to set the stage for the syndrome. The immune response is triggered by viral invasion of traumatized myocardium and an immune response is mounted, not against autologous myocardium per se but against the neo-antigen, the virus-infected myocardium. The illness is self-limited. It sometimes recurs but it seems to leave no sequelae other than the bad memory of a painful postoperative complication that prolonged hospitalization and delayed the realization of the full benefits of that heart operation.