Elderly Woman With Severe, Worsening Dyspnea

Elderly Woman With Severe, Worsening Dyspnea

An 88-year-old woman is admitted for severe dyspnea thathas worsened over the past month. Dyspnea on exertionis now elicited by everyday activities, even walking acrossthe room. Orthopnea and paroxysmal nocturnal dyspneahave progressed to the point that she has been unable tosleep at all the past several nights. She also tires very easilyand thinks her ankles are more swollen than previously.She denies chest pain or pressure.

HISTORY

The patient presented at another hospital a week earlierwith the same complaints, was admitted overnight,and was discharged with prescriptions for several newmedications. However, she says her symptoms seem tohave worsened despite the new regimen. Her primarycare physician has told her she has an "irregular heartbeat"and has treated her for hypertension. Her familysays she has been "failing" for the past year or so. Hermedications currently include digoxin, 0.125 mg/d; metoprolol,50 mg bid; aspirin, 81 mg/d; isosorbide mononitrate,30 mg/d; and furosemide, 80 mg/d.

PHYSICAL EXAMINATION

This ill-appearing woman is in mild respiratory distress.Heart rate is 110 beats per minute and irregularly irregular;respiration rate, 20 breaths per minute; and bloodpressure, 135/60 mm Hg. She is afebrile. Oxygen saturationis 90% to 92% on room air and rises to 96% when 2 L ofoxygen is administered via nasal cannula. Head, eyes,ears, nose, and throat are normal. Neck veins are distendto the angle of the mandible. Examination of the chestreveals bibasilar rales; one examiner notes consolidationsigns in the left lower chest posteriorly. A grade 3/6 diastolicdecrescendo murmur is detected along the left sternalborder. Abdomen is normal. There is 1+ edema of theankles. Neurologic examination reveals no focal signs.

LABORATORY AND IMAGING RESULTS

Hemogram is normal. Results of a chemistry panelinclude a blood urea nitrogen level of 36 μg/dL, creatininelevel of 1.1 μg/dL, and normal potassium level. Atrial natriureticpeptide level is 1360 pg/mL, and digoxin level is0.2 ng/dL. Cardiac enzyme levels are normal.The ECG demonstrates atrial fibrillation (rate, 100beats per minute) and marked left ventricular (LV) hypertrophybut no acute injury currents. Chest radiographshows massive cardiomegaly, a poorly defined left heartborder, and marked pulmonary vascular congestion.After overnight treatment with a vigorous congestiveheart failure regimen (which makes the patient feel better),an echocardiogram confirms moderate to severe aorticregurgitation and reveals the following:

• LV dilatation.
• LV ejection fraction (EF), 45% to 50%.
• Increased thickness of the LV wall.
• Marked aortic root dilatation.
• LV fractional shortening, 27% (normal, greater than 29%).
• End-diastolic dimension, 58 mm (normal, less than55 mm).

Results of blood cultures are negative.

Which of the following is the most appropriate management plan forthis patient?

A.

Initiate a 4- to 6-week course of bactericidal antibiotics to treat bacterialendocarditis.

B.

Attempt medical management with a regimen of vasodilators.

C.

Initiate a course of penicillin to treat rheumatic fever and eradicatestreptococcal infection.

D.

Obtain an urgent thoracic surgery consultation for immediate aorticvalve replacement.

CORRECT ANSWER: B

A number of the findings here are typical of chronic aorticregurgitation (AR). The condition is secondary topathology of either the aortic leaflets or the aortic root,which dilates and deforms the valve leaflet mechanism.Causes of aortic leaflet pathology include infective endocarditisand rheumatic fever, and causes of aortic rootpathology include aortic dissection and Marfan syndrome.This patient most likely has aortic root diseasethat has resulted from idiopathic root dilation, whichis associated with hypertension and aging (commoncauses of AR).

Symptoms and signs of AR.

Both the diastolic decrescendo("blowing") murmur and the widened pulsepressure that are typical of AR are seen here. Widened pulse pressure results when the systolic pulsation of anabnormally large stroke volume is followed by the regurgitationof a large portion of that volume back through thefaulty aortic valve.A vast array of other interesting physical findingshave been observed over the years in patients with AR.These include:

• Quincke pulse (nail bed color changes).
• Musset sign (bobbing head).
• Loud "pistol shot" audible peripheral pulsations.

Echocardiographic findings in AR.

This patient'sAR was confirmed by the echocardiogram, which alsodemonstrated several findings with ominous implicationsregarding disease severity and prognosis. Her EF is"only" 45% to 50%. Patients with AR expel a normal volumeplus the additional regurgitant volume; thus, their EF isusually very high. An EF that is normal or below normal indicates significant LV failure. Other echocardiographicfindings that indicate severe and advanced disease are herabnormal LV fractional shortening and LV end-diastolicdimension. Finally, the echocardiogram shows significantdisease of the aortic root, which means that surgical treatment would involve not only aortic valve replacement butalso repair of the proximal aorta (eg, through resectionand grafting).

Management options.

There is ample clinical andechocardiographic evidence that this patient has severe,advanced, and technically challenging AR. Management isproblematic in this setting. Good data show that surgeryshould be performed to correct AR before severe symptomsdevelop and should be considered in asymptomaticpatients to prevent permanent LV damage.

²

Most expertsagree that elective surgery is best performed before theEF falls below 55%, before the LV end-diastolic dimensionhas increased to more than 55 mm, and before the fractionalshortening has decreased to less than 27%.

^1,2

Thiswoman passed most of these clinical thresholds sometime ago; thus, surgery now poses a higher risk of mortalityor poor clinical outcome. She is also 88 years old,which will make surgery even riskier and more difficult.Finally, there is evidence of aortic root involvement, whichincreases her risk still further. Thus, although surgerymay ultimately be the only effective management option,

immediate

aortic valve replacement (choice D) is likelyoverly aggressive.There is evidence that

vasodilator therapy

-whicheases LV systolic ejection and can improve LV performance,ameliorate clinical symptoms, and delay the needfor surgery-is a good compromise in this patient. Agentsthat have been evaluated in this setting include nitrates,hydralazine, angiotensin-converting enzyme inhibitors,and calcium channel blockers.

³

Her medication regimenrequires adjustment in any event; the β-blocker that wasprescribed for her-presumably to control atrial fibrillation-has probably had a negative impact on her LV function,and its discontinuation might further improve herphysiology. Thus, choice

B,

an attempt at medical managementwith appropriate agents, seems reasonable, atleast initially.A course of bactericidal antibiotics (choice A) or penicillin(choice C) would be appropriate for treatment of theclassic causes of acute AR with only valvular involvement(ie, endocarditis and acute rheumatic fever). However,both are unlikely here on clinical grounds (chronicity, lackof fever); in any event, the echocardiogram and negativeblood cultures essentially exclude them. Still, in any patientwith previously unrecognized AR, blood cultures andan echocardiogram to evaluate for vegetations are reasonablesteps.

Outcome of this case.

The patient's condition steadilyimproved with a regimen of vasodilators (nitrates andnifedipine) and diuretics. Her paroxysmal nocturnal dyspneadisappeared, and her activity tolerance improved.The risks and benefits of surgery and other alternatives were discussed with the patient, her family, and cardiologyand cardiothoracic consultants. The decision was madeto continue with medical management and to reevaluateclinically and echocardiographically in 3 months. At 6weeks, her condition has moderately improved.

References:

REFERENCES:

1.

Carabello BA, Crawford FA. Valvular heart disease. Medical progress.

N EnglJ Med.

1997;337:32-41.

2.

Bonow RO, Carabello B, deLeon AC, et al. ACC/AHA guidelines for the managementof patients with valvular heart disease. Executive summary. A report ofthe American College of Cardiology/American Heart Association Task Force onPractice Guidelines.

J Heart Valve Dis.

1998;6:672-707.

3.

Levine HJ, Gaasch WH. Vasoactive drugs in chronic regurgitant lesions ofthe mitral and aortic valves.

J Am Coll Cardiol.

1996;28:1083-1091.