Severe Aortic Stenosis Concealed by a Negative History in Pregnancy: A Case Report Emphasizing the Diagnostic Cornerstones of History and Physical Examination

Case presentation: A 66-year-old man is referred to a cardiologist for the evaluation of a heart murmur. The patient claims to be entirely asymptomatic, although his wife notes that he has decreased his physical activity over the past two years because he is “getting old.” At physical examination, his blood pressure was 120/70 mm Hg; pulse, 80 bpm; respiration, 13 breaths per minute; and temperature, 99.0°F. Cardiovascular examination revealed normal central venous pressure. His carotid upstrokes were reduced in volume and delayed in upstroke. Cardiac examination revealed a forceful sustained apical impulse in its normal position. There was a 3/6 late-peaking systolic ejection murmur heard at the right upper sternal border radiating to the neck. The rest of the physical examination was unremarkable. Echo-Doppler evaluation revealed an ejection fraction of 0.60, a left ventricular free wall thickness of 1.3 cm, and a peak transaortic flow velocity of 4.5 m/s. How should this patient be managed? Should he undergo aortic valve replacement now? Should he undergo longitudinal follow-up to monitor progression of his aortic stenosis? Over the past 40 years, diagnostic techniques, substitute cardiac valves, and valve implantation surgery have undergone continued improvement, reducing the risk of the valve replacement and enhancing its benefits. Thus, the risk-benefit analysis of valve surgery has tilted in favor of increasingly early intervention for valve disease. The following is a summary incorporating this concept into the current strategy for managing patients with aortic stenosis such as the one described above. The patient with severe aortic stenosis who presents with symptoms represents the most straightforward management strategy for the disease. Survival is nearly normal until the classic symptoms of angina, syncope, or dyspnea develop.1 However, only 50% of patients who present with angina survive 5 years, whereas 50% survival is 3 years for patients who …

Hypertrophy is considered one of the major mechanisms of the myocardium for adapting to hemodynamic overload. More muscle mass provides more contractile elements for generating the extra work required by the overload. In pressure overload of aortic valve stenosis, concentric left ventricular hypertrophy (LVH) normalizes wall stress, a key determinant of ejection performance.1 Afterload is often expressed as wall stress (pressure×radius/thickness). As the pressure term in the numerator increases, it is offset by an increase in the thickness term of the denominator. In this way, the high systolic pressure required to drive blood through even a very stenotic aortic valve can be consistent with normal afterload and normal ejection fraction. See p 3170 Unfortunately, hypertrophy not only provides benefits but also has many pathological consequences. One of these is myocardial ischemia and the attendant angina reported by patients with aortic stenosis despite normal epicardial coronary arteries. The onset of angina greatly increases the risk of sudden death compared with the risk in asymptomatic patients with aortic valve stenosis.2,3 Angina occurs when myocardial oxygen demand exceeds supply. Demand is proportional to heart rate and wall stress, and the latter can be elevated in cases of aortic stenosis when hypertrophy is inadequate to normalize stress.1 After aortic valve replacement, there is marked regression of hypertrophy that may occur over the next several months to years,4 but angina is relieved immediately. Relief of angina immediately after surgery is probably due to the combination of sudden decreased oxygen demand after removal of pressure overload and increased oxygen supply of improved perfusion. However, there are remaining questions about the physiological mechanisms for reduced myocardial oxygen supply (coronary blood flow) in aortic stenosis and its improvement after relief of pressure overload. Specifically, what is it about critical aortic stenosis that is “critical” …

Complications Associated With Nitrate Use in Patients Presenting With Acute Pulmonary Edema and Concomitant Moderate or Severe Aortic Stenosis

The AVATAR Trial for Severe Asymptomatic Aortic Stenosis: Wait or Operate?

Received October 26, 2004; revision received January 13, 2005; accepted February 4, 2005. Calcific aortic valve disease is a slowly progressive disorder with a disease continuum that ranges from mild valve thickening without obstruction of blood flow, termed aortic sclerosis, to severe calcification with impaired leaflet motion, or aortic stenosis (Figure 1). In the past, this process was thought to be “degenerative” because of time-dependent wear-and-tear of the leaflets with passive calcium deposition. Now, there is compelling histopathologic and clinical data suggesting that calcific valve disease is an active disease process akin to atherosclerosis with lipoprotein deposition, chronic inflammation, and active leaflet calcification. The overlap in the clinical factors associated with calcific valve disease and atherosclerosis and the correlation between the severity of coronary artery and aortic valve calcification provide further support for a shared disease process. Figure 1. Gross specimen of minimally diseased aortic valve (left) and severely stenotic aortic valve (right). In the severely stenotic valve, there are prominent lipocalcific changes on aortic side of valve cusps (arrow), with sparing of commissures. ### Anatomy of Normal Aortic Valve The normal aortic valve comprises 3 layers. The ventricularis, on the ventricular side of the leaflet, is composed of elastin-rich fibers that are aligned in a radial direction, perpendicular to the leaflet margin. The fibrosa, on the aortic side of the leaflet, comprises primarily fibroblasts and collagen fibers arranged circumferentially, parallel to the leaflet margin. The spongiosa is a layer of loose connective tissue at the base of the leaflet, between the fibrosa and ventricularis, composed of fibroblasts, mesenchymal cells, and a mucopolysaccharide-rich matrix. These layers work in concert to provide tensile strength and pliability for decades of repetitive motion. ### Early Lesion of Aortic Sclerosis Histopathologic studies of aortic sclerosis show focal subendothelial plaquelike lesions on the aortic side of the leaflet that extend to the adjacent fibrosa layer. Similarities to …

An integrated approach that incorporates two dimensional, M mode and Doppler echocardiographic evaluation has become the standard means for accurate quantification of severity of valvular aortic stenosis. Maximal separation of the aortic valve cusps during systole has been shown to correlate well with the severity of aortic stenosis measured by other echocardiographic parameters. To study the correlation between Maximal Aortic valve Cusp Separation (MACS) and severity of aortic valve stenosis and to find cut-off values of MACS for detecting severe and mild aortic stenosis. In the present prospective observational study, we have compared the accuracy of MACS distance and the aortic valve area calculated by continuity equation in 59 patients with varying degrees of aortic valve stenosis. Aortic leaflet separation in M mode was identified as the distance between the inner edges of the tips of these structures at mid systole in the parasternal long axis view. Cuspal separation was also measured in 2D echocardiography from the parasternal long axis view and the average of the two values was taken as the MACS. Patients were grouped into mild, moderate and severe aortic stenosis based on the aortic valve area calculated by continuity equation. The resultant data regarding maximal leaflet separation on cross-sectional echocardiogram was then subjected to linear regression analysis in regard to correlation with the peak transvalvular aortic gradient as well as the calculated aortic valve area. A cut-off value for each group was derived using ROC curve. There was a strong correlation between MACS and aortic valve area measured by continuity equation and the peak and mean transvalvular aortic gradients. Mean MACS was 6.89 mm in severe aortic stenosis, 9.97 mm in moderate aortic stenosis and 12.36 mm in mild aortic stenosis. MACS below 8.25 mm reliably predicted severe aortic stenosis, with high sensitivity, specificity and positive predictive value. MACS above 11.25 mm practically ruled out significant aortic stenosis. Measurement of MACS is a simple echocardio-graphic method to assess the severity of valvular aortic stenosis, with high sensitivity and specificity. MACS can be extremely useful in two clinical situations as a simple screening tool for assessment of stenosis severity and also helps in decision making non invasively when there is discordance between the other echocardiographic parameters of severity of aortic stenosis.

In adults with valvular aortic stenosis (AS), valve replacement is recommended in the presence of symptoms and severely reduced aortic valve area (AVA).1 In such patients, valve replacement improves symptoms and survival, even in the setting of left ventricular (LV) dysfunction. LV dysfunction in severe AS is usually due to afterload mismatch; valve replacement relieves the afterload excess imposed by the stenotic valve and improves LV performance. 2 However, a subset of patients with “ severe” AS, LV dysfunction, and low-transvalvular gradient has been reported to have a relatively high operative mortality and poor prognosis.2–4⇓⇓ This clinical scenario has been termed “low-flow, low-gradient AS.” Accurate assessment of AVA in such patients is difficult because (1) calculated AVA is directly proportional to forward stroke volume, and (2) the Gorlin constant varies at low-flow states. 5–7⇓⇓ Some patients with low-flow, low-gradient AS have a reduced AVA as a result of inadequate forward stroke volume rather than anatomic stenosis, a situation analogous to reduced anterior mitral leaflet excursion in dilated cardiomyopathy where there is not enough forward flow to fully open the valve. For example, Cannon et al 8 showed that some patients with low-gradient AS were found to have only mild AS at surgery despite a Gorlin AVA indicating critical AS. Obviously, surgical therapy is unlikely to benefit such patients because their primary pathology is a cardiomyopathy. On the other hand, patients with severe anatomic AS may benefit from valve replacement despite the increased operative risk associated with a low-flow, low-gradient hemodynamic state. The recent American College of Cardiology/American Heart Association (ACC/AHA) guidelines for managing valvular heart disease recommends hemodynamic evaluation of low-flow, low-gradient AS using dobutamine echocardiography to distinguish patients with fixed anatomic AS from those with flow-dependent (“ relative”) AS in patients with LV …

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Coagulation disorders and aortic stenosis: a chicken and egg question?

The mechanism of angina pectoris in aortic stenosis is unclear. In their report in this issue of Circulation , Julius et al1 describe several hemodynamic factors in patients with angina pectoris that differ from those in persons without angina in the presence of aortic stenosis. Those patients with aortic stenosis and angina pectoris had lower left ventricular (LV) mass, increased LV peak systolic pressure, increased systolic-diastolic wall stress, smaller left coronary artery diameter, and lower coronary flow reserve compared with persons without angina. The authors conclude that myocardial ischemia and angina pectoris in aortic stenosis are due to inadequate LV hypertrophy, with high systolic and diastolic wall stresses causing reduced coronary flow reserve. Although these factors do differ between the groups of patients with and without angina pectoris in aortic stenosis, there is such great overlap between the groups that these hemodynamic measurements do not correlate specifically with angina pectoris in individuals. Furthermore, it is difficult to explain ischemia on the basis of limited coronary flow reserve when, in fact, there is remaining coronary flow reserve, as indicated by average flow reserves of 1.5 and 1.9 in those with and without angina, ie, 50% to 90% increases in blood flow after dipyridamole administration. Given the wide range of variability and overlap between the groups, it is difficult to ascribe myocardial ischemia to differences in coronary flow reserve when flow reserve was so markedly reduced in both groups. Coronary flow reserve is so comparably reduced in both groups with so much overlap that explaining angina pectoris on the basis of reduced flow reserve is unconvincing. Although the authors have contributed valuable information to this question, their conclusions remain moot. There is a missing link that the authors do not address which is a more specific mechanism for myocardial ischemia and …

Calcific aortic stenosis and its correlation with a novel inflammatory marker, the lymphocyte/monocyte ratio

Calcific aortic stenosis and its correlation with a novel inflammatory marker, the lymphocyte/monocyte ratio

Live longer and better without aortic valve stenosis

Transcatheter aortic valve implantation as rescue therapy for liver transplant candidates with aortic valve stenosis.

The Devoted Grandma: Is a Social Indication for TAVR Acceptable?