The pericardium is composed of a fibrous parietal membrane and a thin visceral membrane. The space between them usually contains <50 ml of plasma ultrafiltrate (1,2). The parietal pericardium is non-compliant – if the fluid accumulates rapidly, the pressure in the pericardial space increases, which can compromise the diastolic filling of the right heart and lead to tamponade (3). However, if the fluid accumulates slowly, the pericardium can enlarge and may accumulate >2,000 ml fluid.
Patients with cancer usually accumulate pericardial fluid slowly (2). This may develop in any type of cancer, but this condition is found with increased frequency in lung cancer, followed by breast cancer and lymphoma (4,5). The incidence of increased pericardial fluid in patients with cancer has been proven in 15%–20% during autopsies (6,7).
We studied 156 oncological patients consecutively presenting with pericardial fluid between 2010 and 2015. There were 74 women and 82 men. Patients ranged in age from 28 to 83 years, with a predilection in the sixth and seventh decades of life.
The electrocardiogram (ECG) of patients with intrapericardial fluid was either normal or with low QRS voltage, ST/T-wave changes, as described in the literature (4,5). The chest X-ray showed enlarged cardiac silhouette when the quantity of the pericardial fluid was high (4,5,8).
Echocardiography (Figure 1) is the most important method of evaluating the presence, location and haemodynamic effect of pericardial fluid on the right heart (2,4,9).
Computed tomography (Figure 2) evaluates the presence, topography and thickness of the pericardial fluid. Especially in oncological patients, thoracic CT scan offers information about other modifications inside the thorax due to the underlying malignancy (tumours, pleurisy, and so on). The CT scan helps the surgeon to choose the appropriate surgical procedure (10,11).
Among all 156 patients with pericardial effusion, 80 were asymptomatic and clinically stable – cardiac follow-up was indicated (clinical symptoms, ECG and cardiac ultrasonography), and they received treatment for the underlying malignancy. Seventy-six patients were symptomatic and needed surgery to evacuate the pericardial fluid. Surgical interventions were performed based on the clinical, biological and oncological status of the patient.
Pericardial effusion appeared most frequently in lung cancer (93 patients), followed by breast cancer (34 patients), lymphoma (eight patients) and other types of neoplasia (Figure 3): five cases of cervical cancer, two cases of melanoma and one each of the following types: renal, endometrial, vulvar, colonic, ovarian, gastric, prostatic, thymic and basal cell carcinomas, lip neoplasm, fibrosarcoma, teratoma and mesothelioma.
More than half of our patients were smokers (88 patients, 56.4%) (Figure 4), probably because of the high number of lung neoplasia cases.
Among the 156 patients, 23 were admitted with cardiac tamponade and managed in emergency.
The surgical interventions for the 76 patients were chosen based on their clinical status, the presence of the tamponade and the possibility to receive general anaesthesia, the topography and quantity of pericardial fluid and the presence of pleural fluid. In addition, the need for pericardial biopsy (expressed by the clinical oncologist) played an important role in choosing the surgical procedure. The surgical procedures performed in our patients were pericardiocentesis (needle-based partial evacuation of the pericardial fluid), subxiphoid pericardial drainage, left paraxifoidian pericardial drainage, pericardiopleural window through intercostal video-assisted thoracic surgery (VATS) or through classical thoracic surgery (12) (Figures 5 and 6).
The rate of recurrence after pericardial drainage was 3.89%. The immediate survival at 48 h was 97.3% (12).
The 80 patients without indication for pericardial drainage were monitored; they received non-steroidal anti-inflammatory drugs, according to cardiologist recommendation, and when indicated by the oncologist, the oncological treatment was continued.
Pericardial effusion may appear in any type of cancer (13). Clinical manifestation may vary from asymptomatic to haemodynamic collapse secondary to cardiac tamponade (1,4,8). The most accurate prevalence data of pericardial effusion come from autopsies, with studies reporting prevalence up to 20% (4,7,12).
The long-term survival of cancer patients with pericardial effusions is not influenced by age or sex and is not affected by the surgical technique used. The type of cancer carries the long-time prognosis in patients with neoplastic pericarditis (8,11). The worst survival rate is in lung cancer, and the best long-term survival is found in lymphomas and breast cancer, mainly because of their good response to chemotherapy (4,8).
In our study, lung cancer was the most frequent type of neoplasia, i.e. 93 out of 156 cases, almost 60%. In fact, the 16 open (through thoracotomy) pericardial fenestrations were performed in patients who intraoperatively proved to have unresectable tumours associated with pericardial fluid – the pericardium was opened for drainage but mainly for intrapericardial assessment of resectability of the tumour. Most of the patients (13 out of 16) had lung cancer, this pathology being the vast majority of presentations in our clinic, as we presented elsewhere (14,15,16,17,18).
The significance of the 48h survival period is that, following the pericardial drainage, the main specific complication is postoperative low cardiac output syndrome (LCOS), pericardial decompression syndrome (PDS) or pericardial shock, which remains the main cause of mortality and, therefore, influences the immediate survival (1,19). To reduce the risk of pericardial shock, we must evacuate the pericardium slowly, monitor the heart and use inotropic support (1,19).
At 5 years after the last enrolled patient, we have 12 patients alive out of 156, i.e. 7.69%. Estimated survival at 5 years is presented in Figure 7, comparing two groups of patients: with or without pericardial drainage. The differences are not statistically significant (
In addition, comparing the calculated survival rate of patients with or without tamponade (Figure 8), we observe the difference to be statistically non-significant, but from the graphs, the patients without tamponade present a better survival.
These two findings support the idea that long-term survival is influenced mainly by the type of malignant disease, similar to the one presented earlier.
Pericardiocentesis can be done rapidly, using only anatomic landmarks and/or echographic guidance, under local anaesthesia. However, it is associated with high rate of recurrence, up to 50%, and a significant mortality and cardiac complications, compared with any other pericardial approach (3,9). In addition, in patients with malignancy, it cannot provide pericardial biopsy when needed.
The lowest rate of recurrence is found for the pericardiopleural window done thoracoscopically or by VATS, followed by subxifoidian and left paraxifoidian drainages (6,11). The subxifoidian and left paraxifoidian approaches are, in fact, ways to evacuate the pericardium, drain it with a tube and obtain pericardial biopsy; after removal of the tube, the pericardium remains opened into the mediastinum – a pericardio-mediastinal fenestration. This is the reason why we perform the pericardial biopsy and fenestration as wide as we can. In our study, the rate of recurrence after pericardial drainage was 3.89%.
In conclusion, the overall prognosis of patients with malignant pericardial effusion remains poor, linked to their underlying malignancy, mainly depending on the response of the malignancy to oncological treatment. The immediate prognosis depends on the pericardial shock complication, also known as postoperative LCOS (low cardiac output syndrome) or PDS (pericardial decompression syndrome). The procedure of surgical drainage of pericardial effusion in each oncological patient must be chosen depending on the presence of tamponade, the quantity of pericardial fluid, the associated pleural effusion and the need for biopsy, offering the maximum possible benefit and safety from the surgical procedure.