The Echocardiographic Characteristics and Prognostic Significance of Pericardial Effusions in Eisenmenger Syndrome

Is pulmonary hypertension protective against cardiac tamponade? A systematic review

The presence of pulmonary hypertension (PH) may affect whether cardiac tamponade physiology develops from a pericardial effusion. Specifically, the increased intracardiac pressure and right ventricular hypertrophy associated with PH would seemingly increase the intrapericardial pressure threshold at which the right-sided chambers collapse. In this systematic review, we examined the impact of PH on the incidence, in-hospital and long-term mortality, and echocardiographic findings of patients with cardiac tamponade. Using the PRISMA guideline, a systematic search was conducted in PubMed, Academic Search Premier, Web of Science, Google Scholar, and the Cochrane Database for studies investigating PH and cardiac tamponade. The Newcastle-Ottawa Scale was used to analyze the quality of returned studies. Primary outcomes included the incidence of cardiac tamponade, as well as in-hospital and long-term mortality rates. Secondary outcomes were the presence or absence of echocardiographic findings of cardiac tamponade in patients with PH. Forty-three studies (9 cohort studies and 34 case reports) with 1054 patients were included. The incidence of cardiac tamponade was significantly higher in patients with PH compared to those without PH, 2.0% (95% CI 1.2-3.2%) vs. 0.05% (95% CI 0.05-0.05%), p < 0.0001, OR 40.76 (95% CI 24.8-66.9). The incidence of tamponade in patients with a known pericardial effusion was similar in those with and without PH, 20.3% (95% CI 12.0-32.3%) and 20.9% (95% CI 18.0-24.1%), p = 0.9267, OR 0.97 (95% CI 0.50-1.87). In patients with tamponade, those with PH demonstrated a significantly higher in-hospital mortality than those without PH, 38.8% (95% CI 26.4-52.8%) vs. 14.4% (95% CI 14.2-14.6%), p < 0.0001, OR 3.77 (95% CI 2.12-6.70). Long-term mortality in patients with tamponade was significantly lower in those with PH than in those without PH, 45.5% (95% CI 33.0-58.5%) vs. 59.1% (95% CI 54.7-63.4%), p = 0.0258, OR 0.576 (95% CI 0.33-1.01). However, after stratifying by non-malignant etiologies, the long-term mortality benefit for those with PH disappeared. In the studies that described specific echocardiographic findings of cardiac tamponade, only 10.5% of patients with PH and tamponade showed right atrial and right ventricular collapse. When evaluating patients with pericardial effusions, physicians must recognize the effects of underlying PH on the incidence, in-hospital and long-term mortality rates, and potentially atypical echocardiographic presentation of cardiac tamponade.

State-of-the-Art Review: Echocardiography in Pulmonary Hypertension

Pulmonary hypertension is a progressive and often fatal disease that frequently presents with dyspnoea on exertion and results in increased right ventricular afterload and right ventricular failure. Although cardiac catheterisation is required for a formal diagnosis, transthoracic echocardiography (TTE) has a central role as a screening tool in those with symptoms and those at risk for developing pulmonary vascular disease. Echocardiographic techniques can be employed to estimate pulmonary artery pressure and resistance, right atrial pressure as well as to derive indirect information about right heart structure and function. Potential causes for pulmonary hypertension may also be identified such as congenital heart disease or left ventricular diastolic dysfunction. An increasing body of evidence has demonstrated the important prognostic utility of echocardiographic data in pulmonary hypertension and highlighted the potential for TTE to help clinicians understand whether treatment responses have been adequate or an escalation in therapy is necessary, as therapeutic options continue to expand for patients with pulmonary arterial hypertension. Although traditional echocardiographic techniques only allow surrogate measures of right ventricular systolic function due to the complex shape of the chamber, newer techniques have enabled three-dimensional assessment of the right ventricle to assess right ventricular volume and contractility. This review will discuss traditional methods as well as newer echocardiographic methods in the setting of pulmonary hypertension.