Carlo Pisacane

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 (LV) remodeling and endocardial and midwall mechanics, and (2) identify factors that might predispose to persistent abnormalities. Sex- and age-specific cutoff levels for LV mass/height2.7 and relative wall thickness were defined to assess LV geometry. To adjust for age-and growth-related changes in ventricular mechanics, all echocardiographic variables were expressed as a Z-score relative to the normal distribution. In addition, the smallest diameter of the aorta was assessed by magnetic resonance imaging and calculated as percent narrowing compared with the diameter of the aorta at the diaphragmatic 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 hypertrophy. LV hypertrophy was marked (LV mass index >51 g/m2.7) in 5 of these patients. No patient had a pattern of concentric hypertrophy. LV contractility was increased (Z-score >95th percentile) in 28 patients (70%) as assessed using the endocardial stress-velocity index. In contrast, LV contractility assessed using midwall stress-velocity index remained elevated (Z-score >95th percentile) in 15 patients (37.5%). The stepwise multiple logistic regression analysis was not able to detect any significant independent predictor of abnormal LV remodeling, including sex, age at surgical repair, length of postoperative follow-up, heart rate, body mass index, systolic and diastolic blood pressure, and smallest diameter of the aorta, as well as indexes of LV geometry (shape, mass, volume, mass/ volume ratio) and function (preload, afterload, pump function, and myocardial contractility). Thus, normotensive patients after surgical repair of aortic coarctation may be in an LV hyperdynamic cardiovascular state (more frequent in those who have undergone late repair) and have multiple patterns of LV geometry.

Hemodynamic effects of a single oral dose of enalapril among children with asymptomatic chronic mitral regurgitation

BACKGROUND Angiotensin-converting enzyme inhibitors have been shown to have beneficial effects in the short- and long-term treatment of adult patients with chronic mitral regurgitation. The safety and efficacy of such treatment have not been established for children. The objective of this study was to assess the effect of the angiotensin-converting enzyme inhibitor enalapril on the severity of valvar mitral regurgitation and the systolic performance of overloaded left ventricle of children. METHODS Ten patients 3 to 16 years of age (mean age 9.6 +/- 3.8 years) with moderate to severe chronic mitral insufficiency were examined by means of Doppler echocardiography before and 2 hours after receiving a single oral dose of enalapril (0.40 mg/kg). Effective regurgitant orifice area, regurgitant volume and fraction, left ventricular end-diastolic and end-systolic volumes indexed for body surface area, left ventricular pump function (total ejection fraction), left ventricular contractility (stress-adjusted velocity of shortening) and afterload (peak systolic and end-systolic circumferential wall stress), and systemic vascular resistance were calculated before and after treatment. RESULTS The following values decreased significantly compared with baseline values: effective regurgitant orifice area (36.2 +/- 17.4 versus 25.9 +/- 16.5 mm(2), P =.00008), regurgitant volume (53.6 +/- 27.4 versus 36.1 +/- 24.5 mL, P =.0002), regurgitant fraction (56.7 +/- 14.5% versus 39.9 +/- 17.0%, P =. 0009), left ventricular end-diastolic volume indexed for body surface area (81.3 +/- 17.4 versus 76.1 +/- 16.1 mL/m(2), P =.005), left ventricular end-systolic volume indexed for body surface area (26.7 +/- 9.1 versus 22.6 +/- 8.9 mL/m(2), P =.02), afterload (peak systolic circumferential wall stress 135.8 +/- 15.3 versus 123.5 +/- 19.7 g/cm(2), P =.005; end-systolic circumferential wall stress 57.8 +/- 12.4 versus 48.3 +/- 12.8 g/cm(2), P =.005), and systemic vascular resistance (2012.2 +/- 536.1 versus 1622.7 +/- 389 dyne. sec. cm(-5), P =.005). Left ventricular pump function increased (total ejection fraction 67.6 +/- 5.7% versus 71.7 +/- 6.5%, P =. 005) without significant changes in left ventricular contractility (stress-adjusted velocity of shortening -0.35 +/- 0.8 versus -0.21 +/- 1.3 SD, P not significant). CONCLUSIONS The data showed that for pediatric patients single-dose treatment with oral enalapril reduces the severity of mitral regurgitation and improves left ventricular loading conditions and systolic performance without impairment of myocardial contractility. Persistence of these unloading effects in long-term therapy might slow the evolution of left ventricular dysfunction caused by overload-induced myocardial damage and possibly delay the time at which surgical repair or replacement of the mitral valve becomes necessary.

Echocardiographic evaluation of left ventricular systolic function in the Down syndrome

Left ventricular systolic function was evaluated by echo-Doppler in 22 Down syndrome patients without congenital heart disease. Although they had evident left ventricular hyperkinesia, this did not appear to reflect intrinsic abnormalities of myocardial properties but a reduced afterload.

Transcatheter closure of complex atrial septal defects: feasibility and mid-term results.

Objective Transcatheter closure of atrial septal defects (ASDs) is currently a reliable alternative to surgery, even though challenging in the case of complex septal anatomy. The aim of this study was to evaluate the feasibility and mid-term results of percutaneous closure of complex ASDs in a tertiary referral centre compared with simple ASD closure. Methods Between April 2000 and November 2004, 209 patients were submitted to transcatheter ASD closure; 83 patients (39.7%) presented with a complex defect (large ASDs with a deficient rim or a multifenestrated/aneurysmal septum) and were treated using different devices tailored to the atrial septal anatomy. Results The transcatheter procedure was successful in 72 patients (86.8%), using a single device in 69 patients and two devices in the remaining three patients. Overall, 71 Amplatzer septal occluders, two multifenestrated Amplatzer septal occluders and two Cardioseal/Starflex devices were used. Procedural and fluoroscopy times were 141 ± 45 min and 28 ± 22 min, respectively (P < 0.0001 vs. simple ASD closure for both comparisons). Procedure-related complications were recorded in nine patients (12.5%) (P < 0.01 vs. simple ASD closure). One patient required surgical repair of a femoral arteriovenous fistula and another developed mitral valve dysfunction. Immediate ASD occlusion was recorded in 59.7% of patients, reaching 95.9% at the last follow-up control (P = NS vs. simple ASD closure for both comparisons). Conclusions Percutaneous closure of complex ASDs may be considered technically feasible, relatively safe and highly effective, although the procedure is still significantly more demanding than transcatheter closure of simple ASDs.

Repeat syncopal attacks due to postsurgical right ventricular pseudoaneurysm.

Pseudoaneurysm of the right ventricular outflow tract is a rare lesion caused by disruption of the ventricular wall that allows the blood to leak into the surrounding space. It often complicates surgery involving right ventriculotomy and progressively increases in size, therefore causing airway compression, pulmonary perfusion asymmetry, thromboembolism, and rupture. We report on a patient who developed right ventricular pseudoaneurysm early after surgery for atrio-ventricular septal defect with tetralogy of Fallot and needed emergency surgical repair due to low cardiac output and repeat syncopal attacks.

Left ventricular mechanics after closure of ventricular septal defect: influence of size of the defect and age at surgical repair

To evaluate the influence of the size of the defect and the age of surgical repair on left ventricular mechanics, including geometry, shape, diastolic and systolic function as well as myocardial contractility, we used cross-sectional echo-Doppler to study 20 patients (12 males, 8 females) who had undergone successful surgical closure of a ventricular septal defect. The patients were divided in two groups, corrected early and late, on the basis of the degree of left-to-right shunting (ratio of pulmonary to systemic output of greater or less than 2.5/1) and the age at the surgical repair (older or younger than 2 years of age). The group undergoing early correction included 11 patients, mean age 7.1+/-1.8 years (range 4.2-11.8 years), having surgery at mean age of 1.3+/-0.6 years for a large ventricular septal defect (mean ratio of pulmonary to systemic output of 3.1/1; range 3.4-2.7/1) with a mean postoperative follow-up 4.6+/-1.9 years. The group of nine patients undergoing late correction had a mean age of 11.3+/-4.9 years (range 6.7-17.2 years), with a later surgical repair (mean age 4.7+/-2.7 years) for a moderate-sized ventricular septal defect (mean pulmonary/systemic output ratio 2.1/1; range 2.3-1.7) and a mean postoperative follow-up of 7+/-4.2 years. Each group of surgically repaired patients was compared with a control group matched for age, body surface area and gender. No significant differences were found between the normal controls and those undergoing early correction for any assessed functional index regarding left ventricular geometry (normalized volumes and mass for body surface area, mass/volume and thickness/radius ratios), shape (long axis-short axis ratio), diastolic (mitral and pulmonary venous flow patterns) and systolic (fractional shortening and rate-corrected mean velocity of circumferential fibre shortening) function. In addition, the data points for each patient for the rate-corrected mean velocity of circumferential fibre shortening to end-systolic stress relationship were within the 95% confidence limits of normal, suggesting normal left ventricular contractility. On the other hand, the patients undergoing surgery at a later age showed a persistent increase of the normalized left ventricular end-diastolic volume and mass, with an higher mass/volume ratio and reduced end-systolic stress compared with normal controls. Furthermore, left ventricular shape (long axis-short axis ratio) was abnormal at end-diastole but with its normal values at end-systole. Our data suggest that, in the presence of a large ventricular septal defect, early successful surgical repair <2 years of age results in complete recovery of left ventricular mechanics in the postoperative follow-up. In contrast, surgical closure at > 2 years of age, even for a moderately sized ventricular septal defect, deleteriously affects postoperative left ventricular geometry and shape. Since prolonged volume overload may be detrimental to myocardial function, earlier surgical repair should be recommended.

Evaluation of left ventricular function in long-term survivors of childhood Hodgkin disease.

Data on the presence of myocardial abnormalities in long‐term Hodgkin disease survivors are contradictory. The purpose of this study was to determine if myocardial performance index (MPI) was capable of discovering cardiac abnormalities.

Left ventricular mechanics after early successful repair of aortic coarctation

A successful aortic coarctectomy performed beyond early infancy is followed, even in the long term, by persistence of left ventricular hypertrophy and by diastolic dysfunction, although systolic function is often increased. In this study we investigated whether earlier coarctectomy provides better preservation of left ventricular function. Experimental studies on the myocardial response to pressure overload show that neonates and young infants develop a functionally advantageous combination of myocytic hyperplasia (together with mild hypertrophy) and increased angiogenesis. Older patients, in contrast, generate myocytic hypertrophy in isolation, setting the scene for ventricular dysfunction. Cross-sectional echo-Doppler evaluation of left ventricular size, shape, mass and systolic and diastolic function was made in 13 patients a mean of 44±36 months (range 11 days-10 years) after successful coarctectomy in the first year of life. They were compared to 11 age, body surface area and gender-matched control subjects. In all patients, left ventricular mass normalized for body surface area was significantly greater than in the control group (66.2±12.3 vs 43±l2 p=0.0001). There was no correlation between left ventricular mass normalized for body surface area and age at operation, follow-up duration, degree of residual isthmic gradient, peak systolic wall stress, systolic blood pressure or left ventricular shape. No significant differences were noted between the two groups in regard to transverse diameter of the aortic arch, left ventricular afterload (meridional end-systolic wall stress), volume and shape (both in systole and diastole), systolic performance (fractional shortening and ejection fraction) and contractility (rate-corrected velocity of fiber shortening to meridional end-systolic wall stress relationship). Furthermore, no significant differences were found with respect to indices of mitral (including peak filling rate normalized to mitral stroke volume) and pulmonary venous flow, suggesting normal diastolic function. Repair of aortic coarctation in the first year of life promotes a more complete recovery of left ventricular function (particularly diastolic) than that reported after coarctectomy at older age, despite persistence of moderate ventricular hypertrophy.