Role of Doppler and imaging echocardiography in selection of patients for cardiac valvular surgery

Doppler echocardiography in familial hypertrophic cardiomyopathy: the French Cooperative Study

Familial hypertrophic cardiomyopathy (HCM) has been poorly studied, although it may represent 50% of all HCM. We studied 346 subjects belonging to 20 unrelated families. Patients were considered affected in view of left ventricular (LV) wall thickness. One hundred twenty-seven adults were considered affected, id est. had a left ventricular wall thickness (LVWT) > 13 mm, whereas 123 had a LVWT > 15 mm, suggesting that the cut-off value is usually not critical. Within affected patients, 95% had an asymmetrical HCM (interventricular septum/left posterior wall thickness > 1.3 mm), whereas 84% had a ratio > 1.5. Distribution of the affected patients according with Maron's classification are in keeping with published studies about sporadic forms. Doppler derived isovolumetric relaxation time was prolonged in HCM (105 +/- 23 vs 88 +/- 16 msec, P < 0.001), and the ratio peak velocity of A wave over peak velocity of E wave was significantly lower in affected individuals (0.99 +/- 0.56 vs 0.83 +/- 0.46, P < 0.05). None of the 24 children studied (10 +/- 3 years) were considered affected according to echocardiographic criteria.

CONCLUSION

Echocardiography is the obligatory first step during genetic study for recognizing familial HCM. It allows classification in adults but not in children. Doppler estimate of diastolic function may be helpful in the future to recognize genetically affected subjects with normal or subnormal echocardiographic examination.

Quantitative assessment of aortic regurgitation by combined two-dimensional, continuous-wave and colour flow Doppler measurements

The width of the regurgitant jet at the aortic valve plane, i.e. the core flow diameter, the ratio of the jet width to the left ventricular outflow diameter, the regurgitant volume and regurgitant fraction were determined using two-dimensional, continuous wave and colour flow Doppler echocardiography. The relationship between the non-invasive measurements and semiquantitative angiographic grading of the regurgitant flow (1 + to 4+) was examined in a primary group of 20 patients with chronic aortic regurgitation. Cut-off points for the non-invasive measurements were selected so as to separate patients with mild or moderate regurgitation (1+ or 2+) from patients with moderately severe or severe regurgitation (3+ or 4+). These cut-off points were prospectively applied in a new group of 35 patients with aortic regurgitation to predict the angiographic grading. Jet width correctly predicted the angiographic grading in 86% of cases, the ratio of the jet width to the outflow diameter in 83% of cases, the regurgitant volume in 86% of cases and the regurgitant fraction in 91% of cases. We conclude that the severity of aortic regurgitation as determined by angiographic grading can be estimated with reasonable accuracy by non-invasive techniques based on colour flow imaging.

Valvular heart disease. A correctable cause of congestive heart failure

Surgical repair of mitral, aortic, and tricuspid valves and balloon valvuloplasty for mitral stenosis are being done more and more often. These complex procedures require accurate and high-quality imaging techniques to guide the physician in decision making before surgery and in assessment of success during surgery. Dr Currie describes the use of echocardiography in diagnosis and management of patients with various forms of valvular heart disease.

The value of Doppler echocardiography in the management of patients with valvular heart disease: analysis of one year of clinical practice

Management recommendations based on Doppler echocardiographic examination and cardiac catheterization were compared in a prospective study in 100 consecutive patients who were admitted for evaluation and treatment of suspected valvular heart disease during 1988. Management recommendations were provided independently after both Doppler echocardiography and cardiac catheterization by different and blinded investigators. Criteria for severe (clinically significant) and moderate to mild (insignificant) valvular lesions and management recommendations were agreed on in advance. There was disagreement on the severity of aortic stenosis based on the aortic valve area and maximum instantaneous pressure gradient in 1 of 54 patients, which resulted in differing management recommendations. Mitral stenosis was severe (valve area less than or equal to 1 cm2) at Doppler echocardiography but not at cardiac catheterization in 5 of 14 patients. Because pulmonary artery pressure increase during exercise at cardiac catheterization also suggested severe obstruction, management recommendations were similar. There was a potentially significant disagreement on the severity of aortic regurgitation in 9 of 76 patients and of mitral regurgitation in 14 of 90 patients; however, this did not produce differing management recommendations because with most patients coexistent valvular lesions or an impaired ventricular function mainly determined the ultimate management decision. Although of good quality, Doppler echocardiographic examination was nonconclusive for clinical decision-making in 15% of the study population because of uncertainty about the severity of mitral regurgitation or aortic regurgitation or because of problems in assessing the degree of left ventricular dysfunction in patients with severe regurgitation.(ABSTRACT TRUNCATED AT 250 WORDS)

Factors affecting Doppler echocardiographic valve area assessment in aortic stenosis

Doppler echocardiographic assessment of the aortic valve area (AVA) using the continuity equation was performed before cardiac catheterization in 100 patients with suspected aortic stenosis. Doppler echocardiographic AVA correlated closely with AVA calculated by the Gorlin equation at catheterization (r = 0.96). However, Doppler echocardiography slightly but systematically underestimated the AVA (p less than 0.001) and did so most markedly in patients with mild stenosis (greater than 1.0 cm2). In multivariate analysis, the difference in AVA by the 2 techniques was positively associated with left ventricular (LV) stroke volume and inversely with the difference between mean catheterization and Doppler gradients, LV ejection fraction and LV outflow tract velocity. Furthermore, the AVA difference also was related to gender, being larger in women. Thus, overall Doppler echocardiography reliably assesses AVA, but the usefulness of the method is somewhat reduced by its underestimation of AVA in mild stenosis. This drawback, however, is usually overcome by taking patients' symptoms into account. Furthermore, lacking a "gold standard," this underestimation need not imply errors of the Doppler echocardiographic method alone, but also may reflect known inaccuracies of the catheterization technique.

Clinical evaluation versus Doppler echocardiography in the quantitative assessment of valvular heart disease

We tested the hypotheses that Doppler echocardiography has a higher accuracy than clinical evaluation in the detection of significant aortic and mitral valvular heart disease and that Doppler echocardiography is highly accurate as compared with cardiac catheterization for the assessment of valvular disease severity. Thus, cardiac catheterization for the assessment of valve lesion severity may be unnecessary in selected patients. We prospectively evaluated 75 consecutive patients, ages 20-74 years (mean, 52 years), with clinically suspected valvular heart disease. Specific clinical and Doppler echocardiographic criteria were used to categorize each valve lesion as absent, insignificant, or significant. Criteria for a significant lesion at cardiac catheterization was an aortic or mitral valve area less than 1.1 or 1.5 cm2, respectively, or equal to or greater than 3+ cm2 aortic or mitral regurgitation at angiography. In all valve lesions, Doppler echocardiography had a higher overall accuracy than clinical evaluation. Increases in accuracies of 28%, 19%, 15%, and 7% occurred for mitral stenosis, aortic stenosis, aortic regurgitation, and mitral regurgitation, respectively, resulting in overall accuracies of 97%, 100%, 95%, and 96%. Clinical evaluation alone made 28 errors (37% of patients and 19% of valve lesions assessed), and 17 of these errors (23% of patients and 12% of valve lesions) would have resulted in inappropriate management. In only four (24%) of these 17 patients, the attending cardiologist would not have proceeded to assess the valve at cardiac catheterization.(ABSTRACT TRUNCATED AT 250 WORDS)