April 1st, 2021
Cardiac tamponade is a clinical syndrome of hemodynamic abnormalities that result from compression of the heart chambers due to increased intrapericardial pressure; this can be due to the accumulation of blood, pus, effusion (transudate or exudate) or air within the pericardial space. The hallmark of cardiac tamponade is the rapid rise and equalization of pressures in all cardiac chambers to levels similar to that of the pericardial sac (i.e., 20-25 mmHg).
Cardiac tamponade is most common in the setting of pericarditis, cardiac intervention and malignancy. Chest trauma, cancer, active infection, renal failure, liver disease or aortic dissection are less common causes. In developed countries, invasive cardiac procedures—especially those that require intraprocedural anticoagulation and left atrial access—are the most common cause of acute cardiac tamponade.
Dyspnea is the most common symptom. It is caused by pulmonary congestion due to reduced cardiac output and impaired systemic venous return.
Chest pain and chest discomfort are other common symptoms, resulting from stretching and irritation of the pericardium.
Patients with cardiac tamponade may experience palpitations due to the increased adrenergic tone. This normally results in sinus tachycardia, but atrial arrhythmias can also occur.
Patients with subacute tamponade may present with right upper quadrant pain due to hepatic venous congestion.
The possibility of cardiac tamponade should be considered in all patients presenting with shock. Shock occurs because the rising intrapericardial pressure causes the interventricular septum to bulge into the LV. This reduces LV diastolic compliance, leading to a progressive decrease in stroke volume and blood pressure.