A 20-year-old woman presents to the clinic with fever and arthritis. She reports that she developed these symptoms over the past few days, and the pain seems to be jumping from one joint to the next. There is no significant medical or family history, and she does not smoke or use illicit drugs. She reports that she had a throat infection 3 weeks ago, but she denies any recent exposure to sick contacts or recent sexual activity. The patient has a temperature of 38.6°C, blood pressure of 124/78 mmHg, heart rate of 88 beats per minute, respiratory rate of 16 breaths per minute, and oxygen saturation of 100% on room air. On examination, she has a 2/6 blowing systolic murmur at the apex. There is erythema and swelling of her knees as well as her left elbow and wrist, and there are no skin or nail findings. Her white blood cell count is 15,000/mm3 and the erythrocyte sedimentation rate is 45 mm/h. Antistreptolysin O titers are positive; blood cultures are drawn and are negative.
Which of the following is the most likely diagnosis?
Rheumatic fever. One complication of untreated group A Streptococcal infection is rheumatic fever, which is an autoimmune disease that usually occurs 2 to 4 weeks after pharyngitis. It is usually seen in adolescents and is rare in adults. Diagnosis is made using the modified Jones criteria: evidence of strep infection plus two major criteria or one major criterion and two minor criteria. Major criteria include migratory polyarthritis, carditis, erythema marginatum (ring-like macular rash), Sydenham chorea, and subcutaneous nodules. Minor criteria include fever, arthralgia (painful joints without swelling), leukocytosis, elevated ESR or CRP, AV block on ECG, and previous rheumatic heart disease. This patient has two major criteria (polyarthritis and carditis) and three minor criteria (fever, leukocytosis, and elevated ESR), making the diagnosis of rheumatic fever likely. The murmur of mitral regurgitation in this patient is likely a result of valvulitis (meeting the criterion of carditis), since rheumatic fever can cause inflammation of any heart structure from the pericardium to the endocardium. Patients should be treated with antibiotics (penicillin) and aspirin if carditis is present.
(A) Rheumatoid arthritis may present with fever and symmetric polyarthritis; however, the temporal relation to pharyngitis should make the reader suspect rheumatic fever instead. (B) Gonococcal arthritis is a good diagnosis to consider in young sexually active patients presenting with fever, polyarthritis, and skin lesions (usually pustules). When this diagnosis is considered, cultures should be drawn from multiple sites (cervix, anus, synovium, etc.) to increase the diagnostic sensitivity; however, this patient is not sexually active and does not have any skin findings. (D) Infective endocarditis is diagnosed using the modified Duke criteria, which she does not meet. She has a new regurgitant murmur on examination; however, this can also occur in rheumatic fever from valvulitis.
A 38-year-old immigrant woman comes to the Emergency Department with right-sided weakness and slurring of her speech. Initial imaging and studies are obtained, and she is found to have suffered an ischemic stroke and is treated appropriately. When you go to examine her, she has an irregularly irregular pulse, and on cardiac examination she has an early diastolic high-pitched opening snap at the apex followed by a low-pitched diastolic rumbling murmur. Upon further discussion with the family, they indicate that she does not have any chronic medical problems and has not been to the doctor since she was a baby. She had frequent throat infections as a child, but these always resolved without treatment. She takes no medications and does not smoke or drink alcohol.
The mechanism by which this condition developed is most similar to which of the following other conditions?
Guillain–Barré syndrome. This is a difficult question that assumes a strong understanding of mitral stenosis, including the mechanism, diagnosis, and potential complications. This woman suffered a stroke, which is rare in her age group. A careful reading of the vignette shows that the patient had mitral stenosis and atrial fibrillation, both of which increase the propensity for a clot to form in the left atrium and embolize to the cerebral circulation to cause an ischemic stroke. The patient’s history, obtained from her family, raises the suspicion for rheumatic heart disease as the cause of the patient’s mitral stenosis. This is a common cause of mitral stenosis in developing countries and usually becomes symptomatic in the 30s. It is caused by Streptococcus pyogenes (Group A β-hemolytic strep). This is a reason why strep throat is important to diagnose and treat with antibiotics. Rheumatic heart disease is usually caused by repetitive strep infections, which was seen in this patient. The mechanism can be explained by the process of molecular mimicry, in which antibodies developed after exposure to an infectious agent cross-react with self antigens. One of these self antigens is present on the mitral valve, causing an autoimmune reaction which leads to scarring with subsequent repair and fibrosis, ultimately resulting in stenosis of the mitral valve. (E) Guillain–Barré syndrome is similarly a result of autoantibodies developed after exposure to an infectious agent (Campylobacter, Mycoplasma, viruses such as CMV and HIV, etc.) via the same mechanism of molecular mimicry. It results in an ascending paralysis due to demyelination of peripheral nerves.
peripheral nerves. (A) Infective endocarditis may affect the mitral valve, but damage of the valve commonly leads to a regurgitant murmur (rather than stenosis). The mechanism is by direct infection of the valve and not by an autoimmune process. (B) Cystic fibrosis is an autosomal recessive disease caused by a mutation in the CFTR gene encoding a chloride channel. (C) Graves disease is the result of autoantibodies against the TSH receptor, causing unregulated stimulation and secretion of thyroid hormone. There is no preceding infectious agent, and the autoantibodies are activating (not destructive). (D) Sarcoidosis is a granulomatous autoimmune disease but is not preceded by an infectious agent causing molecular mimicry.
A 42-year-old woman is brought to the hospital after losing consciousness. She was at an outdoor graduation ceremony when her daughter’s name was called and she stood up with excitement. After she stood up, she felt lightheaded, nauseous, and started to develop tunnel vision. She tried to sit down but forgets what happened at this point. She awoke seconds later and was alert. She has a history of diabetes and GERD and takes metformin and omeprazole. There is no family history of heart disease or seizures. She is currently comfortable with no abnormalities on physical examination. Her blood pressure is normal and it does not change after going from a seated to a standing position.
Vasovagal syncope. Syncope is defined as loss of consciousness that results from cerebral hypoperfusion. The most common cause of syncope is neurocardiogenic (vasovagal) syncope, which is caused by a sudden surge of sympathetic activity that transiently increases the contractility of the left ventricle. Mechanoreceptors in the left ventricle sense this increased contractility and cause an excessive vagal response, which lowers heart rate and contractility. This transiently drops the blood pressure and causes syncope. These patients typically have symptoms of lightheadedness, nausea, and narrowing vision prior to losing consciousness and can usually brace their fall somewhat. Diagnosis can be made with the tilt table test
(A) Cardiovascular causes of syncope include arrhythmias, mechanical heart disease (e.g., aortic stenosis and hypertrophic cardiomyopathy), pulmonary embolism, aortic dissection, and cardiac tamponade. Patients with sudden onset syncope and trauma to the face (indicating an inability to brace the fall) should increase the reader’s suspicion for a cardiac etiology. (B) Orthostatic hypotension usually occurs in the presence of hypovolemia, dysautonomia, and/or certain medications (e.g., diuretics and β-blockers). Diagnosis can be made if systolic blood pressure decreases by ≥20 mmHg or diastolic blood pressure decreases by ≥10 mmHg when going from a sitting to a standing position, which was not seen in this patient. (C) Seizures technically do not meet the definition of syncope, since they are not caused by a disruption in cerebral blood flow. History that would indicate a seizure include a preceding aura, tonic–clonic movements during the episode, and a postictal state (confusion with gradual improvement in neurologic function).
A 52-year-old woman presents with fatigue, peripheral edema, and periorbital purpura. She states that the symptoms of fatigue and peripheral edema have developed gradually over the past few months, but the periorbital skin changes occurred abruptly after sneezing. She also experiences dyspnea after moderate exertion, which is abnormal for her. Her vitals are within normal limits. Her jugular veins are distended, and there are third and fourth heart sounds. Her lungs are clear bilaterally and she has pitting edema around the ankles. A urinalysis reveals significant proteinuria, and an ECG shows low voltages throughout all the leads. The patient is admitted and a cardiac biopsy is performed. The tissue is stained with Congo red and shows apple-red birefringence under polarized light.
Which of the following is the correct diagnosis?
Amyloid cardiomyopathy. The stain showing apple-red birefringence should lead the reader to suspect amyloidosis as the cause of this patient’s restrictive cardiomyopathy. There are several types of amyloidosis that can cause restrictive cardiomyopathy, and in this case the patient most likely has the AL form that is a primary disease process resulting from a plasma cell dyscrasia. In this form of the disease, light chain proteins are deposited in tissues throughout the body, and the heart is commonly affected with a poor prognosis. The periorbital purpura is fairly specific for the AL form. Inherited amyloidosis and senile amyloidosis fall into a separate category called ATTR amyloidosis, which results from an autosomal dominant mutation in the gene encoding transthyretin. The AA form occurs as a secondary disease process that results from deposition of serum amyloid A protein. It may occur with chronic inflammatory conditions such as rheumatoid arthritis or inflammatory bowel disease; however, this form does not commonly lead to heart disease. Treatment in AL amyloidosis is twofold: chemotherapy for the underlying process, and treatment of the heart failure with typical agents (although ACE inhibitors and β-blockers are typically not tolerated in amyloid cardiomyopathy).
(B) Hypertrophic cardiomyopathy would show an S4 but not an S3 on examination, and would show left ventricular hypertrophy on ECG (not low voltages as is seen with infiltrative processes like amyloidosis). (C) Rheumatoid arthritis can cause inflammation of heart structures (pericarditis, endocarditis, etc.), but she has no other suggestive symptoms. It may cause AA amyloidosis; however, this form does not typically affect the heart. (D) Hemochromatosis can cause a restrictive cardiomyopathy but this typically presents in men with skin darkening, arthritis, diabetes, and liver disease. (E) Temporal arteritis is a vasculitis that presents in older patients with fever, headache, jaw claudication, and tenderness over the temporal arteries. It is often associated with polymyalgia rheumatica. Biopsy of the temporal artery shows intimal thickening and granulomatous inflammation.
A 46-year-old man with a history of familial hypercholesterolemia is admitted to the hospital for chest pain. He is found to have a massive myocardial infarction and undergoes PCI. The following day, the patient becomes hypotensive, and on examination he has distant heart sounds.
Which of the following should be avoided in this patient?
Immediate pericardiocentesis. This patient is presenting with a complication of a massive MI, which is ventricular free wall rupture leading to cardiac tamponade. This usually occurs within the first few days after an MI and presents with Beck’s triad of cardiac tamponade: hypotension, distended neck veins, and muffled/distant heart sounds. Free wall rupture leading to tamponade may also present with pulseless electrical activity. As blood accumulates in the pericardial sac, it exerts pressure on the heart and causes an equalization of pressure within the four chambers. During inspiration, blood is drawn into the right ventricle due to the negative intrathoracic pressure, and the interventricular septum deviates into the left ventricle and reduces left ventricular preload, and therefore the cardiac output. A paradoxical elevation in jugular venous pressure during inspiration may be seen in cardiac tamponade, but is also seen in other conditions including constrictive pericarditis (Kussmaul sign). This is a life-threatening situation, and immediate surgery is often necessary.
(D) The patient is hemodynamically unstable, and all the choices except pericardiocentesis are appropriate in this setting. (A) IV fluids can increase preload for adequate filling of the ventricles, which can help to offset the decreased cardiac output. (B) Inotropic agents may be necessary to support the blood pressure since he is hypotensive. Immediate pericardiocentesis is not a good option in this case, since it will not correct the underlying problem (a hole in the ventricular wall); drawing off a small amount of fluid in the setting of pulseless electrical activity may be appropriate, but in this scenario the patient should undergo immediate surgery to correct the ventricular defect.
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