Pericardial annual incidence and prevalence of pericardial
Pericardial effusion is a common finding in clinical practice either as incidental finding or manifestation of a systemic or cardiac disease. The spectrum of pericardial effusions ranges from mild asymptomatic effusions to cardiac tamponade. Moreover, pericardial effusion may accumulate slowly or suddenly(1).Pericardial effusion is very common after cardiac surgery.
Despite the high incidence of effusion, the clinical approach to this problem remains controversial. Once pericardial effusion is documented, serial echocardiographic studies are frequently performed, at considerable expense(2). Unfortunately, there are few epidemiological data on the incidence and prevalence of such effusions in the clinical setting. In Maria Vittoria hospital, an urban general hospital in Torino and an Italian referral center for pericardial diseases, the mean annual incidence and prevalence of pericardial effusion have been, respectively, 3 and 9% in a 6-year experience of the echo laboratory (2000–05) (3). Such data mainly depend on the epidemiological background (especially developed vs. developing country, where tuberculosis is a leading cause of pericardial disease and concurrent HIV infection may have an important promoting role) (4), the institutional setting (tertiary referral center compared to secondary and general hospitals), and the availability of specific subspecialties (especially nephrology, rheumatology, and oncology). Furthermore, since postoperative PE or pericardial tamponade (PT) may present without prominent clinical signs and findings, there is a potential risk for life-threatening events. The delayed presentation of PE or PT may arise several days to weeks after the operation.
In these clinical situations, early diagnosis would aid in the early treatment(5). Pericardial drainage procedures can be performed for diagnostic or therapeutic purposes (patients with cardiac tamponade). In patients without hemodynamic compromise the diagnostic yield of pericardial fluid or pericardial tissue is very low(6). Patients with echocardiographic collapses rarely require pericardial drainage for therapeutic purposes during the initial admission. Therefore, pericardial drainage procedures are not justified on a routine basis in patients without hemodynamic compromise.
Three exceptions to this rule should be noted. Patients with a strong suspicion of purulent or tuberculous pericarditis merit invasive pericardial procedures(7). In contrast, in patients with underlying malignancies examination of pericardial fluid is indicated so as to determine whether the effusion is secondary to neoplastic pericardial involvement or is an epiphenomenon (non-malignant effusion) related to the management of the cancer (such as previous thoracic irradiation) or effusions of unknown origin(7).
In a nutshell, a wide variety of pathologic conditions may cause pericardial effusion leading to pericardial tamponade. Cardiac tamponade requires drainage to prevent cardiac decompensation and death. The effusion can be drained by needle or catheter pericardiocentesis, subxiphoid pericardial drainage(8),pericardial window performed through a left anterior thoracotomy(9), pericardiectomy performed by an open thoracotomy(10), or video-assisted thorascopic (VATS) pericardiectomy(11). The most effective method of drainage to prevent recurrence is subject to controversy(12). In the present study, our primary goal was to assess the benefits and drawbacks of posterior pericardial drainage in patients undergoing heart surgery.Study Selection and CriteriaSearch results were screened by scanning abstracts for the following Inclusion Criteria1- Randomized controlled trials (RCTs) and controlled clinical trials (CCTs).2- Study comparing strategy of posterior pericardial drainage with no intervention to the pericardium during heart surgery.
3- Studies reporting outcomes of interest within the investigated follow-up.Exclusion Criteria1- Narrative reviews or case reports.2- Non RCTs.The study was done according to the ethical board of King Abdulaziz university.Statistical Analysis• Cochran Q test was used.• Primary index Statistics: Odds ratios (ORs) and 95% confidence intervals (CIs) as for dichotomous outcomes.• Continuous outcomes: mean difference and corresponding 95% CIs calculated by the use of a random effects model.
• Pooled ORs were calculated via the Mantel-Haenszel model (13)with weight assigned to each included study adjusted to include a measure of variation (?2) in the effects reported between studies.• In the case that degree of heterogeneity exceeded 40%, an inverse variance (DerSimonian-Laird) random-effects model was applied. As a preferred approach when intervention effects are small (ORs are close to one) and events are not particularly common, estimates were calculated by the use of the fixed-effects Peto method(14). In case there were “0 events” reported in both arms, calculations were repeated, as a sensitivity analysis, by the use of risk difference and respective 95% CIs.Moreover, an attempt was made to explore the possible relationship between age, sex, hypertension, type 2 diabetes, type of the surgery, mean number of grafts, duration of cardiopulmonary bypass, cross clamp, and study total number of patients and the occurrence of primary endpoint. v.
2 (Biostat, Englewood, NJ) (15) were used for statistical computations. P values ?.05 were considered statistically significant and reported as 2-sided, without adjustment for multiple comparisons.RESULTS Searches identified 1174 publications in addition to another 21 publications that were found through manual research. After removal of duplicates, abstracts and titles,733 publications were assessed as identified from title and abstract, and 230 papers were excluded. 87 papers full text could not be retrieved and another 340 papers with the same cohort. There were also 317 papers excluded because they did not compare different surgical techniques or did not report an adhesion-related outcome. We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) (16)guidelines in reporting the results.
Figure 1Most of the studies included 2 drains which were placed at the end of surgery: one in the left pleural cavity while the other was placed in the anterior mediastinum, the pericardium however was left open anteriorly. PP was and comprised a longitudinal, 4-cm long incision parallel and posterior to the phrenic nerve, extending from left inferior pulmonary vein to the diaphragm in most cases. Zhao et al. (25) reported intervention-related complications; one case of postoperative bleeding due to dropping of the hemoclip from the inverse-T incision. Furthermore, Tables 1 represents baseline characteristics of all studies included in the present meta-analysis while table 2 demonstrates the secondary medical condition of the cases