Search

Background: Restrictive mitral annuloplasty is the preferred method of treating secondary mitral regurgitation. The use of small annuloplasty rings to reduce the high recurrence rates may result in mitral stenosis., Methods: Thirty-six patients who underwent restrictive mitral annuloplasty with Carpentier-Edwards classic 26 size ring underwent exercise echocardiography and ergospirometry. Resting catecholamines and N-terminal pro brain natriuretic peptide (NT-proBNP) levels were measured., Results: At the time of study, the median time from operation was 16.6 months (interquartile range, 8.5 to 43.3 months). Left ventricular end-systolic volume index (LVESVI) was 67 mL/m(2) (interquartile range, 25 to 92 mL/m(2)), and ejection fraction (EF) was 38.8% (interquartile range, 28.3% to 59.0%). Mitral gradients were higher at the leaflet tips than at the annular level. Continuous wave (CW) Doppler gradients at rest were 3.4 mmHg (interquartile range, 2.4 to 4.9 mmHg) mean and 9.5 mmHg (interquartile range, 7.0 to 14.7 mmHg) maximal. On exertion, they increased to 6.8 mmHg (interquartile range, 5.4 to 8.8 mmHg) (p = 0.001) and 19.7 mmHg (interquartile range, 12.8 to 23.3 mmHg) (p = 0.001), respectively. Maximal VO2 was 18.2 mL/kg/min (interquartile range, 16.3 to 21.5 mL/kg/min), VE/VCO2 slope was 31.1 (interquartile range, 26 to 34). Epinephrine level was 0.024 ng/mL (interquartile range, 0.0098 to 0.043 ng/mL), norepinephrine was 0.61 ng/mL (interquartile range, 0.41 to 0.95 ng/mL), and NT-proBNP was 303 pg/mL (interquartile range, 155 to 553 pg/mL). Maximal VO2 negatively correlated with resting norepinephrine level (r = -0.50, p = 0.003). VE/VCO2 slope positively correlated with NT-proBNP (r = 0.36, p = 0.004) and epinephrine (r = 0.36, p = 0.04) levels and with LV volumes (r = 0.51, p = 0.006) and was negatively correlated with LVEF (r = -0.52, p = 0.004). Neither maximal VO2 nor VE/VCO2 slope correlated with the highest mean (r = 0.24, p = 0.2, and r = -0.20, p = 0.3, respectively) and maximal (r = 0.13, p = 0.5, r = -0.20, p = 0.3, respectively) mitral gradients on exertion., Conclusions: Restrictive mitral annuloplasty for secondary mitral regurgitation does result in a degree of mitral stenosis; however, primary heart disease seems more important for patient's exercise performance than the mitral stenosis resulting from using an undersized ring., (Copyright © 2015 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Objectives: It remains unclear why some patients with cardiomyopathy secondary to anterior infarction do, and others do not develop functional mitral regurgitation (MR)., Methods: Thirty-six patients after anterior infarction with ejection fraction (EF) below 35%, 18 with no/trivial and 18 with moderate/severe MR, underwent cardiac magnetic resonance imaging. Parameters describing the geometry of the mitral valve, subvalvular apparatus and left ventricle were measured., Results: The septolateral and commissure-to-commissure mitral annular diameters were bigger in patients with MR. The odds ratio (OR) of developing regurgitation was 25.0 (95% confidence interval [95% CI] 4.3-144.3; P < 0.001) for end-systolic septolateral mitral annulus diameter above 20 mm/m(2). MR was less likely in patients with straighter posterior papillary muscle (OR 0.040, 95% CI 0.007-0.23; P < 0.001-for the angle between muscle axis and mitral annulus plane >81°), and more likely (OR 7.9, 95% CI 1.6-39.4; P = 0.008) with posterior papillary muscle tethering >23 mm/m(2). Regurgitation was less likely (OR 0.032, 95% CI 0.003-0.33; P = 0.001) with anterolateral papillary muscle tip to ipsilateral mitral annulus distance in end-diastole longer than 13 mm/m(2). Left ventricular EF, volumes and the overall end-systolic and end-diastolic wall thicknesses did not differ between the groups. Patients with MR had thinner myocardium proximal to the base of the anterior and distal to the base of the posterior papillary muscle., Conclusions: Inferior extension of anterior infarction and more leaning posterior papillary muscle are the major components resulting in the development of ischaemic MR in patients with cardiomyopathy secondary to anterior infarction. Shorter chordae tendineae may constitute the anatomical background that makes the development of ischaemic MR more likely., (© The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.)