Left ventricular remodeling and mechanics after successful repair of aortic coarctation

Forty normotensive patients (mean age 12.3 +/- 6.5 years) followed up after a successful repair of aortic coarctation (mean age at coarctectomy 5.1 +/ - 4.8 yrs) were studied by echo-Doppler to (1) evaluate left ventricular (L V) remodeling and endocardial and midwall mechanics, and (2) identify facto rs that might predispose to persistent abnormalities. Sex- and age-specific cutoff levels for LV mass/height(2.7) and relative wall thickness were def ined to assess LV geometry. To adjust for age- and growth-related changes i n ventricular mechanics, all echocardiographic variables were expressed as a Z-score relative to the normal distribution. In addition, the smallest di ameter of the aorta was assessed by magnetic resonance imaging and calculat ed as percent narrowing compared with the diameter of the aorta at the diap hragmatic level. In the study group, 24 of 40 patients (60%) had normal LV geometry. Among the 16 patients (40%) with abnormal LV geometry, 5 (12.5%) had a pattern of concentric remodeling and 11 (27.5%) an eccentric hypertro phy. LV hypertrophy was marked (LV mass index >51 g/m(2.7)) in 5 of these p atients. No patient had a pattern of concentric hypertrophy. LV contractili ty was increased (Z-score >95th percentile) in 28 patients (70%) as assesse d using the endocardial stress-velocity index. In contrast, LV contractilit y assessed using midwall stress-velocity index remained elevated [Z-score > 95th percentile) in 15 patients (37.5%). The stepwise multiple logistic reg ression analysis was not able to detect any significant independent predict or of abnormal LV remodeling, including sex, age at surgical repair, length of postoperative follow-up, heart rate, body mass index, systolic and dias tolic blood pressure, and smallest diameter of the aorta, as well as indexe s of LV geometry (shape, mass, volume, mass/ volume ratio) and function (pr eload, afterload, pump function, and myocardial contractility). Thus, normo tensive patients after surgical repair of aortic coarctation may be in an L V hyperdynamic cardiovascular state (more frequent in those who have underg one late repair] and have multiple patterns of LV geometry. (C) 2001 by Exc erpta Medico, Inc.