CONGENITAL AORTIC STENOSIS PRODUCED BY A UNICOMMISSURAL VALVE

Unicuspid aortic valve presenting with cardiac arrest in an adolescent

Unicuspid aortic valve (UAV) is a rare congenital anomaly typically affecting patients in their fourth and fifth decades and presenting with signs of heart failure. Our case is one of a previously asymptomatic teenage girl with a UAV, who presented with cardiac arrest and was successfully treated. Only two other similar cases have been reported in the literature, both were of slightly older male patients. Our case highlights the morbidity associated with the anomaly supporting the need for careful assessment of the valve in cases where UAV is suspected.

Natural history of adults with congenitally malformed aortic valves (unicuspid or bicuspid)

Appreciation of the frequency of the congenitally malformed aortic valve has come about during the last 50 years, a period during which aortic valve replacement became a predictably successful operation. Study of patients at necropsy with either a congenitally unicuspid (1 true commissure) or bicuspid (2 true commissures) valve in whom no aortic valve operation has been performed has not been conducted during these 50 years, to our knowledge. We studied 218 patients at necropsy with congenitally malformed aortic valves: 28 (13%) had a unicuspid valve and 190 (87%), a bicuspid valve. Their ages at death ranged from 21 to 89 years (mean, 55 yr), and 80% were men. Of the 218 adults, the aortic valve functioned normally during life in 54 (25%) and abnormally in 164 (75%): aortic stenosis in 142 (65%), pure aortic regurgitation without superimposed infective endocarditis (IE) in 2 (1%), and IE superimposed on a previously normally functioning aortic valve in 20 (9%). IE occurred in a total of 31 (14%) of the 218 patients: involving a previously normally functioning valve in 20 (65%) and a previously stenotic valve in 11 (35%). Of the 218 patients, at least 141 (65%) died as a consequence of aortic valve disease (124 patients) or ascending aortic tears with or without dissection (17 patients). An estimated 1% of the population, maybe higher in men, has a congenitally malformed aortic valve. Data from this study suggest that about 75% of them will develop a major complication. Conversely, and encouragingly, about 25% will go through life without a complication.

Clinical and Morphologic Features of the Congenitally Unicuspid Acommissural Stenotic and Regurgitant Aortic Valve

Five adults, aged 30-75 years, are described with stenotic and regurgitant unicuspid acommissural aortic valves. Because none of these patients had clinical, echocardiographic or hemodynamic evidence of mitral valve disease, a case is made that these valves were congenitally malformed and not the result of an acquired condition.

Coronary artery dilatation and aortic outflow tract enlargement in children with unicommissural aortic valves

We evaluated the aortic outflow tract (AOT) and coronary artery dimensions in pediatric patients with unicommissural aortic valves. A retrospective review of an echocardiographic database identified 37 patients with unicommissural aortic valves. A total of 115 echocardiograms were reviewed, and the right coronary artery (RCA), left main coronary artery (LM), left anterior descending coronary artery aortic valve annulus, aortic root, sinotubular junction (STJ), and ascending aorta were measured and z scores determined. The aortic stenosis peak gradient and the amount of aortic regurgitation (AR) were also measured. The RCA diameter (z score, 1.85 +/- 1.8, p = 0.03) and LM diameter (z score, 1.74 +/- 1.47, p = 0.04) are significantly dilated, as are all the AOT measurements: aortic annulus (2.02 +/- 1.9, p = 0.02), aortic root (2.25 +/- 1.9, p = 0.02), STJ (2.22 +/- 1.74, p = 0.01), and ascending aorta (4.38 +/- 2.03, p < 0.001). Longitudinal follow-up showed that there was no significant variation over time in any variable. The AOT measurements were significantly correlated with each other. A trend was found in which an increasing amount of AR gave an increase in AOT measurements. The aortic gradient was not significantly associated with any measurement. Our study population demonstrated significant dilatation of the RCA and LM as well as the AOT. The dilatation of the AOT structures is likely caused by the same mechanism that accounts for the AOT dilatation in patients with bicommissural aortic valves. Dilatation of the coronary arteries may represent an intrinsic abnormality in the vessel wall. Further studies are needed to define possible changes.

Congenital Heart Surgery Nomenclature and Database Project: aortic valve disease

The extant nomenclature for aortic valve disease is reviewed for the purpose of establishing a unified reporting system. The subject was debated and reviewed by members of the STS-Congenital Heart Surgery Database Committee and representatives from the European Association for Cardiothoracic Surgery. All efforts were made to include all relevant nomenclature categories using synonyms where appropriate. Aortic valve disease has been subdivided into stenotic and regurgitant lesions. Stenotic lesions have been characterized by anatomic location: supravalvar, valvar, and subvalvar. Regurgitant lesions have been characterized as either congenital or acquired. A comprehensive database set is presented that is based on a hierarchical scheme. Data are entered at various levels of complexity and detail that can be determined by the clinician. These data can lay the foundation for comprehensive risk stratification analyses. A minimum database set is also presented that will allow for data sharing and would lend itself to basic interpretation of trends. Outcome tables relating diagnoses, procedures, and various risk factors are presented.

Comparison of age, gender, number of aortic valve cusps, concomitant coronary artery bypass grafting, and magnitude of left ventricular-systemic arterial peak systolic gradient in adults having aortic valve replacement for isolated aortic valve stenosis

Correlation of the structure of the operatively excised aortic valve with various clinical variables has received relatively little attention. This report describes certain observations in 115 patients aged >30 years (mean age 70) who had aortic valve replacement for aortic valve stenosis unassociated with mitral valve dysfunction. The operatively excised aortic valve was congenitally unicuspid in 3 patients (3%), congenitally bicuspid in 54 patients (47%), tricuspid in 57 patients (50%), and of uncertain structure in 1. Of the 87 patients (76%) aged > or =65 years (Medicare population), 36 (41%) had congenitally malformed valves (bicuspid in each), and of the 28 patients (24%) aged <65 years, 21 (75%) had congenitally malformed valves. A higher percentage of patients with congenitally malformed valves had peak systolic pressure gradients across the valve >50 mm Hg than did patients with tricuspid valves (57% vs 43%). Concomitant coronary artery bypass grafting (CABG) was performed in 52 patients (45%) (34 men and 18 women), and they had average peak systolic pressure gradients across the valve significantly lower than patients without coronary bypass (46 vs 64 mm Hg): 39% of the 57 patients with congenitally malformed valves and 53% of the 57 patients with tricuspid valves had concomitant coronary bypass (insignificant difference). Thus, in a relatively older population of 115 patients having aortic valve replacement for isolated aortic valve stenosis, with or without associated aortic regurgitation, one half had congenitally malformed valves (either unicuspid or bicuspid valves) and one half had tricuspid valves. Patients having concomitant CABG had significantly smaller gradients across the stenotic valves than those who had no CABG.

Long-term follow-up of valvulotomy for congenital aortic stenosis

The data were reviewed of 42 patients who had valvulotomy for severe aortic valve stenosis before 1968. All were over age 2 years (mean age 11.3 years). The mean time of follow-up after surgery was 10.6 years (range 6 to 16.3 years). No patient died at operation. Two late deaths were from endocarditis with aortic regurgitation, and one patient with severe arotic regurgitation died suddenly; three patients had valve replacement for aortic regurgitation and one required repeat valvulotomy. Five patients could not be traced. Major symptoms were alleviated in all patients. Left ventricular pressures were obtained in 15 patients before and after operation; the mean gradient averaged 100 mm Hg before and 43 mm Hg after operation. No patient had significant aortic regurgitation before operation. Twelve had moderate to severe regurgitation after operation. The incidence of late valve calcification at a mean time of 10.6 years after operation was small, and restenosis was uncommon. Because moderate or severe incompetence can be produced and stenosis is often incompletely relieved, the operation is palliative, but the low morbidity and mortality rates suggest that it is an effective procedure if stenosis is severe and life-threatening.

Congenital aortic stenosis resulting from a unicommisssural valve. Clinical and anatomic features in twenty-one adult patients

Clinical, electrocardiographic, phonocardiographic, radiographic, hemodynamic, and anatomic findings are presented in 21 adult patients with stenotic unicommissural aortic valves. Distinction between congenitally unicuspid and bicuspid aortic valves before operation or autopsy was not possible. Although the basic structure of the valve may render it inherently stenotic, the age at which a murmur was first noted (average, 19 years), the duration of a known murmur (average, 25 years), and the age of onset of first symptoms of left ventricular outflow obstruction (average, 41 years) strongly suggest that stenosis at least in part is acquired. The relationship of the true and false commissures to the coronary arterial ostia could be determined with certainty in 12 patients. The basic division of the aortic valve into left, right, and noncoronary cusps is maintained, but the raphes do not extend to the valve orifice. Because the aortic valve is attached to the ascending aorta at only one point (the true commissure), which is at the level of the orifice, valvotomy is hazardous, and valve replacement appears indicated when operative treatment becomes necessary in the adult patient with a stenotic unicommissural aortic valve.