An Elderly Woman in Heart Failure
An 81-year-old woman presents with worsening edema. In recent weeks, significant swelling of both legs has developed. In addition, she is less ambulatory, not only because of her swollen legs but also because she becomes short of breath when she walks even short distances. During the previous week, she was awakened twice from sleep with dyspnea and has placed a fan near her bed. She has also felt “dizzy” at times and close to fainting.
For many years, she has had type 2 diabetes mellitus as well as hypertension. She admits that her adherence to her medication regimen is not good. Her prescribed medications are furosemide 80 mg/d, lisinopril 10 mg/d, metformin 1000 mg/d, and aspirin 325 mg/d.
This ill-appearing woman is mildly dyspneic. Heart rate is 104 beats per minute; respiration rate, 20 breaths per minute; and blood pressure, 124/90 mm Hg. She is afebrile.
Neck veins are distended. Carotid pulsations are diminished and delayed. The chest examination reveals decreased breath sounds on the right and basal rales bilaterally. Her heart rhythm is regular. There is a coarse grade 4/6 systolic ejection murmur precordially with radiation to the neck. A palpable thrill and an S3 gallop are noted. The patient manifests ascites and anasarca.
An echocardiogram demonstrates an aortic systolic murmur. The aortic valve gradient is 42 mm Hg, and the peak velocity is 4.1 m/sec. The aortic valve area is estimated at 0.75 cm2. Ejection fraction is 35%.
Which of the following is the most accurate statement about this patient’s condition and management?
A. The patient has critical aortic stenosis (AS), but congestive heart failure (CHF) has developed, which makes it too late for surgery.
B. The patient has aortic valve disease and CHF from acute bacterial endocarditis and needs blood cultures and antibiotics.
C. Transcatheter repair will yield similar survival rates at 1 year compared with traditional surgical repair, but with important differences in periprocedural risk, particularly stroke.
D. There will be very little difference between a strategy of more aggressive medical CHF management and any surgical intervention.
Correct Answer: C
Although no history of a prior diagnosis of valvular heart disease is given, this is not really a “new” murmur. She is afebrile, which is a strong negative for endocarditis. The echocardiogram reveals the murmur is AS, not mitral regurgitation (the common murmur of subacute bacterial endocarditis) or aortic regurgitation (the common finding of acute bacterial endocarditis). Thus, her epidemiology and objective cardiac findings are not a good fit for endocarditis and choice B is not correct.
CLINICAL FEATURES OF AORTIC STENOSIS
This patient has acquired AS, most likely resulting from degeneration and calcification of the aortic leaflets. The disease usually becomes clinically evident after the 6th decade.
She displays two of the three findings of the classic triad of AS: angina, syncope, and CHF. Further, she manifests several of the common physical findings of AS. The most typical is her systolic ejection murmur radiating to the neck associated with diminished carotid pulsations in amplitude and time. The delay in the carotid upstrokes and the narrow pulse pressure indicate clinically that the AS is the hemodynamically significant lesion. This is confirmed by Doppler study, which also indicates that the stenosis is critical, namely the gradient exceeds 40 mm Hg, the valve area is less than 0.8 cm2, and the peak velocity exceeds 4.0 m/sec.1
TREATMENT OF AORTIC STENOSIS
The only effective relief for AS is aortic valve replacement. In the setting of CHF, 2-year mortality is 50% without surgery. Age itself is not a contraindication in the absence of comorbid illness. This patient’s significant medical history and comorbidity mandate careful analysis regarding her surgical candidacy and which procedure to use.
Both choices A and D are incorrect because the only effective therapy for AS is surgical. Mortality is 50% at 2 years with even the best medical therapy, and enhancing this patient’s regimen will not effect results superior to this.1
The goal is to determine and improve the patient’s candidacy for a repair intervention. If this can be done, the CHF and related findings will actually improve. These current issues involve which intervention is optimal.
Traditional surgical aortic valve replacement has been the core of AS therapy. The procedure has a surgical mortality of 2.6% overall and less than 5% even in patients older than 80.2
In recent years, a less invasive procedure, transcatheter bioprosthetic aortic valve implantation, has been evaluated in patients who cannot undergo surgery.2,3 Studies have clearly demonstrated that this technique is superior to “medical management” with regard to a variety of parameters, including overall mortality at 1 year, and a variety of cardiac performance measures.3
As is typical, enthusiasm for a less invasive approach translates into increased usage, not just for patients who are ineligible for surgery, but also in place of surgery, even for patients who are surgical candidates.4 A recent trial thus compared surgical repair to transcatheter repair in “high risk” (but operable) patients. As one might expect, during the initial 30 days acute mortality was lower (3.4% vs 6.5%) and hospital stays were shorter in the transcatheter group compared with the surgical group.4 But more importantly, at 1 year survival was equivalent and one of the “periprocedural risks,” major stroke, was significantly more common with transcatheter bioprostheses, with an incidence of 5.1% at 1 year or roughly double the incidence in the traditional surgery group.4 In their enthusiasm for the transcatheter technique, the trial authors emphasized that it would increase the number of patients who could be offered some form of replacement4; whereas the author of the accompanying editorial cautioned against substituting the newer technique—with its worrisome incidence of stroke complication—for traditional repair in patients who are otherwise eligible for surgery.5
OUTCOME OF THIS CASE
This patient underwent medical evaluation, and on the basis of the Society of Thoracic Surgeons score, she was deemed a reasonable candidate for surgery.2,6 She tolerated a surgical repair, and at 6 months after the operation, she is clinically well with New York Heart Association class I heart failure.
1. Carabello B. Aortic stenosis. N Engl J Med. 2002;346:677-682.
2. Lazar HL. Transcatheter aortic valves—where do we go from here? N Engl J Med. 2010;363:1667-1668.
3. Leon MB, Smith CR, Mack M, et al. Transcatheter aortic-valve implantation for aortic stenosis in patients who cannot undergo surgery. N Engl J Med. 2010;363:1597-1608.
4. Smith CR, Leon MB, Mack MJ, et al. Transcatheter versus surgical aortic-valve replacement in high-risk patients. N Engl J Med. 2011;364:2187-2198.
5. Schaff HV. Transcatheter aortic-valve replacement—at what price? N Engl J Med. 2011;364:2256-2258.
6. Gross EA, Schwartz CF, Yu PJ, et al. High risk aortic-valve replacement: are outcomes as bad as predicted? Ann Thorac Surg. 2008;85:102-106.