A34-year-old woman presents to the emergency department(ED) with rapidly progressive dyspnea.The patient has a history of metastatic vaginal clearcell adenocarcinoma secondary to diethylstilbestrol exposurein utero. Following her diagnosis in 1990, she wastreated with surgery, chemotherapy, and radiation. Shehad done well for years until a recurrence of the cancer tothe left lung was found last year. She completed a courseof chemotherapy with doxorubicin hydrochloride andcisplatin 1 month ago.
A 34-year-old woman presents to the emergency department(ED) with rapidly progressive dyspnea.The patient has a history of metastatic vaginal clearcell adenocarcinoma secondary to diethylstilbestrol exposurein utero. Following her diagnosis in 1990, she wastreated with surgery, chemotherapy, and radiation. Shehad done well for years until a recurrence of the cancer tothe left lung was found last year. She completed a courseof chemotherapy with doxorubicin hydrochloride andcisplatin 1 month ago.One week before the patient's ED visit, acute rightupper quadrant abdominal pain, ascites, and dyspnea developed.Before she arrived at the ED, she was profoundlydyspneic at rest and had experienced episodes of nearsyncopewhen standing.The patient has no history of cardiovascular illness,chest pain, dyspnea on exertion, orthopnea, peripheraledema, or abdominal distention. She has had no recentfevers, cough, or malaise. She previously had good exercisetolerance. She is not taking any medications. Shedoes not smoke, drink alcohol, or use illicit drugs.On examination, the patient is in acute distress; sheis pale and tachypneic. Her blood pressure is 86 mm Hgby palpation; her heart rate is 130 beats per minute. A pulsusparadoxus is noted. Her respiration rate is 26 breathsper minute, and oxygen saturation is 93% on room air.When sitting upright, she has jugular venous distention tothe level of the jaw. She has decreased breath sounds atthe bases. Her heart sounds are distant and alternate inintensity. The liver is palpable 2 finger breadths below thecostal margin and pulsatile. Her abdomen is distendedand ascites is present. Her extremities are cool, and thereis 1+ peripheral edema. Her ECG is shown.1. What cardiac diagnosis best explainsthe clinical findings?2. What abnormalities are evident on thepatient's ECG?3. Which other management measures arerecommended?1. What cardiac diagnosis best explains the clinicalfindings?This patient has pericardial tamponade. The clinicalsyndrome that develops when pericardial fluid interfereswith diastolic filling is related to the rapidity of fluid accumulation,the quantity of fluid, and the distensibility ofthe pericardium. As little as 100 mL of rapidly accumulatingfluid can produce tamponade, although a large quantityof fluid developing slowly may not interfere with cardiacfunction. The most common causes of pericardialtamponade in medical patients are infectious pericarditis(of viral, bacterial, mycobacterial, or fungal origin); malignantpericardial effusions; irradiation-induced injury;collagen vascular disease; and uremia.Impaired diastolic ventricular filling reducesstroke volume. The heart rate increases to maintaincardiac output and a narrow pulse pressure subsequentlyoccurs. As impairment of filling becomes moresevere, hypotension and shock ensue. Increased rightsidedpressures distend the jugular veins, and pulsusparadoxus can be elicited. Pulsus paradoxus is causedby more pronounced limitation of left ventricular fillingduring inspiration because of the left ventricle's interactionwith the right ventricle.Among the most common early symptoms of pericardialtamponade are dyspnea during exertion andfatigue. If tamponade develops gradually, peripheraledema and GI symptoms (including abdominal fullnessresulting from hepatomegaly or ascites) may be noted.Late symptoms include dyspnea at rest, chest pain,dizziness, and syncope.2. What abnormalities are evident on the patient'sECG?The ECG shows sinus tachycardia at a rate of122 beats per minute. In addition, "electrical alternans,"the beat-to-beat alternation in the amplitude of the QRScomplex, is evident in all 12 leads (Figure). This ECGfinding, characteristic of pericardial tamponade, is believedto be caused by periodic swinging of the heartwithin the fluid-filled pericardium.3. Which other management measures arerecommended?Further evaluation of patients with suspected pericardialtamponade should include urgent echocardiography,which can demonstrate a pericardial effusion as anecho-free space around the heart. Echocardiography canalso show collapse of the right atrium and right ventricleduring diastole. A pendular swinging motion of the heartis also seen. The diagnosis of pericardial tamponade isconfirmed by catheterization of the right heart, whichreveals equalization of diastolic pressures in all cardiacchambers.Pericardiocentesis is performed as an emergenttherapeutic measure. In this patient, 750 mL of bloodyfluid was drained, which resulted in relief of her symptomsand restoration of her blood pressure. After theprocedure, an ECG showed resolution of both tachycardiaand electrical alternans. Cytologic analysis of thepericardial fluid revealed malignant cells.Therapeutic options for the prevention of recurrentsymptomatic pericardial effusions include intrapericardialsclerotherapy, subxiphoid pericardiotomy, and percutaneousballoon pericardiotomy.