Quantitation of the Mitral Tetrahedron in Patients With Ischemic Heart Disease Using Real-Time Three-Dimensional Echocardiography to Evaluate the Geometric Determinants of Ischemic Mitral Regurgitation

Background: Ischemic mitral regurgitation (IMR) is common in ischemic heart disease and results in poor prognosis. However, the exact mechanism of IMR has not been fully elucidated. Hypothesis: Quantitation of the mitral tetrahedron using three-dimentianl (3D) echocardiography is capable of evaluating the geometric determinants and mechanisms of IMR. Methods: Forty patients with a history of ST-elevation myocardial infarction at least 6 months earlier were studied. Parameters of mitral deformation and global left ventricular (LV) function and shape were evaluated by 2-dimensional echocardiography. The effective regurgitant orifice (ERO) of IMR was obtained by the quantitative continuous-wave Doppler technique. Three-dimensional (3D) echocardiography was applied to assess the mitral tetrahedron. Results: Mitral valvular tenting area (P<0.001), mitral annular area (P=0.032), dilation of the LV in diastole, impairment of the LV ejection fraction, and volume of the spherically shaped LV in systole were greater in patients with an ERO >= 20 mm(2) than in those with an ERO <20 mm(2). In the mitral tetrahedron, only the interpapillary muscle roots distance showed a significant difference (P=0.004). Multivariate analysis with the logistic regression model showed the systolic mitral tenting area (odds ratio [OR]: 280.49, 95% confidence interval [CI]: 4.59-1.72 x 10(4), P=0.007) and interpapillary muscle distance (OR: 1.50, 95% CI: 1.03-2.19, P=0.036) to be independent factors in predicting significant IMR (ERO >= 20 mm(2)). Conclusions: 3D echocardiography can be effectively applied in measuring the mitral tetrahedron and evaluating the mechanism of IMR. Mitral valvular tenting and interpapillary muscle distance are 2 independent factors of significant IMR

Late Outcome of Patients with Aortic Dissection: Study of a National Database

Objectives: The incidence of late mortality and morbidity of aortic dissection remained unchanged during the past 20 years. The present study was to analyze the risk factors of late events for patients with aortic dissection. Methods: A total of 5654 cases of aortic dissection (3871 males) were collected from the National Health Insurance Databases from 1996 to 2001. Age, gender, Marfan syndrome, and initial treatment modality were the main factors to be investigated. Corrective group was defined by surgical operation with cardiopulmonary bypass and palliative group for the remaining. Late aortic events were defined by late aneurysmal evolution of diseased aorta needing surgical intervention or death of aortic causes from 6 months to 6 years. Results: The incidence of aortic dissection was 43 per 1 000 000 population in our country. Corrective group accounted for 19.3% of them and palliative group for 80.7%. Marfan syndrome accounted for 1.5% of all cases (4.31% of corrective surgery group). The rate of freedom from mortality at 1, 6 months, and 6 years was 80.4 +/- 1.3, 69.0 +/- 1.5, and 56.5 +/- 2.9% for corrective group and 89 .5 +/- 0.5 78.4 +/- 0.6, and 46.1 +/- 1.35% for palliative group. Nearly half of the late mortalities were attributed to atherosclerosis-related conditions (cardiac, stroke, or aortic causes). The incidence of late aortic events was 2.48 % per year on an average. comparable between corrective and palliative groups. This incidence increased since the fourth year after their initial episode. For corrective group. young age was a risk factor of late aortic events (relative risk of 0.60-0.82 per decade, P = 0.037). For palliative group, Marfan syndrome and male Lender were risk factors of late aortic events (relative risk of 4.08-10.7, P < 0 .001 in the former; relative risk of 1.46-2.1, P = 0.002 in the latter). Conclusions: Late aortic events were not uncommon for both corrective and palliative groups, and its incidence increased since the fourth year after their initial episodes. Young age for corrective group, Marfan syndrome and male gender for palliative group were risk factors of late aortic events. (C) 2004 Elsevier B.V. All rights reserved

Functional mitral regurgitation in chronic ischemic coronary artery disease: Analysis of geometric alterations of mitral apparatus with magnetic resonance imaging

Background: Patients with chronic coronary artery disease have double the mortality rate if the condition is combined with functional mitral regurgitation. An understanding based on geometric alterations of the mitral apparatus in functional mitral regurgitation is desirable. Methods: Twenty-nine subjects were enrolled in the study, including 9 healthy volunteers (control group), 12 patients with chronic coronary artery disease without functional mitral regurgitation (CAD group), and 8 patients with chronic coronary artery disease with functional mitral regurgitation (CADFMR group). Cine magnetic resonance imaging was performed to acquire multiple short-axis cine images from base to apex. Left ventricular end-systolic volume, left ventricular ejection fraction, mitral area, and vertices of the mitral tetrahedron, defined by medial and lateral papillary muscle roots and anterior and posterior mitral annulus, were determined from reconstructed images at end-systole. Anterior-posterior annular distance, interpapillary distance, and annularpapillary distance (the distance from the anterior or posterior mitral annulus to the medial or lateral papillary muscle roots) were calculated. Results: Left ventricular end-systolic volume was inversely associated with left ventricular ejection fraction (R2 0.778). Left ventricular end-systolic volume was highly associated with distances related to ventricular geometry (R2 0.742 for interpapillary distance, 0.792 for the distance from the anterior mitral annulus to the medial papillary muscle root, and 0.769 for distance from the anterior mitral annulus to the lateral papillary muscle root) but was moderately associated with distances related to annular geometry (R2 0.458 for anterior-posterior annular distance and 0.594 for mitral area, respectively). Moreover, interpapillary distance of greater than 32 mm and distance from the anterior mitral annulus to the medial papillary muscle root of greater than 64 mm readily distinguished the CADFMR group from the other groups. Conclusion: In patients with coronary artery disease, an increase in left ventricular end-systolic volume is associated with inadequate approximation of the mitral tetrahedron during systole, which consequently leads to functional mitral regurgitation. Our study suggests that interpapillary distance and distance from the anterior mitral annulus to the medial papillary muscle root are sensitive to the increase in left ventricular end-systolic volume and reliably indicate the presence of functional mitral regurgitation

Functional Mitral Regurgitation in Chronic Ischemic Coronary Artery Disease: Analysis of Geometric Alterations of Mitral Apparatus with Magnetic Resonance Imaging

Background: Patients with chronic coronary artery disease have double the mortality rate if the condition is combined with functional mitral regurgitation. An understanding based on geometric alterations of the mitral apparatus in functional mitral regurgitation is desirable. Methods: Twenty-nine subjects were enrolled in the study, including 9 healthy volunteers (control group), 12 patients with chronic coronary artery disease without functional mitral regurgitation (CAD group), and 8 patients with chronic coronary artery disease with functional mitral regurgitation (CAD+FMR group). Cine magnetic resonance imaging was performed to acquire multiple short-axis cine images from base to apex. Left ventricular end-systolic volume, left ventricular ejection fraction, mitral area, and vertices of the mitral tetrahedron, defined by medial and lateral papillary muscle roots and anterior and posterior mitral annulus, were determined from reconstructed images at end- systole. Anterior- posterior annular distance, interpapillary distance, and annular-papillary distance (the distance from the anterior or posterior mitral annulus to the medial or lateral papillary muscle roots) were calculated. Results: Left ventricular end-systolic volume was inversely associated with left ventricular ejection fraction (R-2 = 0. 778). Left ventricular end- systolic volume was highly associated with distances related to ventricular geometry (R -2 = 0.742 for interpapillary distance, 0.792 for the distance from the anterior mitral annulus to the medial papillary muscle root, and 0.769 for distance from the anterior mitral annulus to the lateral papillary muscle root ) but was moderately associated with distances related to annular geometry (R-2 = 0.458 for anterior-posterior annular distance and 0.594 for mitral area, respectively). Moreover , interpapillary distance of greater than 32 mm and distance from the anterior mitral annulus to the medial papillary muscle root of greater than 64 mm readily distinguished the CAD+FMR group from the other groups. Conclusion: In patients with coronary artery disease, an increase in left ventricular end-systolic volume is associated with inadequate approximation of the mitral tetrahedron during systole, which consequently leads to functional mitral regurgitation. Our study suggests that interpapillary distance and distance from the anterior mitral annulus to the medial papillary muscle root are sensitive to the increase in left ventricular end-systolic volume and reliably indicate the presence of functional mitral regurgitation