PubMed Health⌕ Search

Biomedical subjects

M G Russo

Publications and source records attributed to M G Russo.

At least 19 recordsLinked to original sources
PubMed2001

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.

Adolescent↗
PubMed2001

New insights in the pathophysiology of mitral and aortic regurgitation in pediatric age: role of angiotensin-converting enzyme inhibitor therapy.

This review has been focused on the new insights in the pathophysiology of mitral and aortic regurgitation and on the role of ACE-inhibitor therapy in children with chronic volume overload due to left-sided valvular lesions. Recent clinical studies show that these drugs have favorable effects when administered orally in chronic mitral and aortic regurgitation. Interestingly, the beneficial effects of ACE-inhibition regard the basic anatomic, hemodynamic and adaptive pathologic conditions related to volume overload, namely, the regurgitant orifice area and volume and ventricular remodeling. The heart is a plastic structure, constantly being altered in size, shape and composition in response to chronic volume overload. Thus, modulation of cardiac plasticity by ACE-inhibition raises the possibility of using new therapeutic strategies specifically designed to prevent and/or antagonize the mechanical disadvantages secondary to volume overload-induced cardiac remodeling. The beneficial effects of ACE-inhibition have also been observed in growing children with asymptomatic valvular regurgitation; thus, it appears that the unloading therapy has the potential of influencing the natural history of both mitral and aortic regurgitation and possibly delays surgical valve repair or replacement. These data justify early inhibition of the renin-angiotensin system in children with left ventricular volume overload due to mitral and aortic regurgitation.

Angiotensin-Converting Enzyme Inhibitors↗
PubMed2000

Echocardiographic assessment of ventricular filling pressure during the second and third trimesters of gestation.

AIMS: To confirm changes in the atrioventricular diastolic flow velocities (peak E, peak A, E/A ratio) with gestational age and to define whether these changes genuinely reflect variations in filling pressure in the fetal heart. METHODS: Fifty normal pregnancies were studied between the 13th and the 37th weeks of gestation. The fetal flow velocity patterns were evaluated by pulsed-wave (PW) Doppler and the annular velocities of the atrioventricular valves by PW-Doppler tissue imaging (DTI). RESULTS: All indexes evaluated (atrioventricular peak flow and annular velocities) correlated significantly with gestational age. This correlation was stronger for the early diastolic indexes (tricuspid E and EA, 0.69 and 0.78; mitral E and EA, 0.61 and 0.77, respectively) and weaker for the end-diastolic indexes (tricuspid A and AA, 0.46 and 0.37; mitral A and AA, 0.45 and 0.39, respectively). Neither mitral nor tricuspid E/Ea ratio changed significantly with gestational age. CONCLUSIONS: The lack of correlation between the Doppler-assessed ventricular filling pressures and gestational age suggests absence of significant changes of ventricular compliance during the second and third trimesters of pregnancy, and a progressive enhancement of active relaxation and/or changes in loading conditions.

Adult↗
PubMed2000

Hypertrophic cardiomyopathy in pediatric patients: effect of verapamil on regional and global left ventricular diastolic function.

OBJECTIVE: To assess the effects of treatment with verapamil on regional and global left ventricular (LV) diastolic function in paediatric patients with hypertrophic cardiomyopathy (HCM). DESIGN: Twelve patients (age range 5.1 to 12.3 years, median 8.6) with HCM were evaluated during ongoing chronic oral treatment with verapamil (4 mg/kg/day) and four days after withdrawal of therapy. Twelve age- and body surface area-matched normal children served as controls. In an echocardiographic study, global LV diastolic function was evaluated by assessing isovolumic relaxation time (IVRT) and mitral flow indexes, including peak filling rate normalized to mitral stroke volume (PFR/SV). In addition, regional LV diastolic function was assessed by pulsed-wave Doppler tissue imaging at the subendocardial portion of the middle region of the anterior and posterior interventricular septum, and anterolateral and inferior walls to measure the peak velocities and the velocity-time integrals of myocardial excursion in both early diastole and atrial systole. In addition, as an index of diastolic asynchrony (AsyI), the variation in time to peak filling rate, measured as the time from the peak of the R wave on the electrocardiogram to the peak of the regional E wave, among the four myocardial regions was defined by subtracting the smallest value from the greatest and expressing the difference as a percentage of the smallest value. RESULTS: Compared with the controls, patients with HCM without therapy showed a longer IVRT (P<0.01) and a decrease in PFR/SV (P<0.01) without a compensatory increase in filling during atrial systole. Oral administration of verapamil induced a significant shortening of the IVRT (P=0.003) and an increase in PFR/SV (P=0.02). Furthermore, patients with HCM without therapy showed a significantly longer time to peak filling rate (P<0.01) associated with a decreased peak velocity in early diastole without a concomitant increase in peak velocity during atrial systole in each of the myocardial regions. Furthermore, the AsyI was higher in the HCM group than in controls (19% versus 6%, respectively), and this index was inversely correlated with the PFR/SV (r=-0.86, P<0.001). The regional diastolic velocity of the myocardium at each of the four analyzed regions was not significantly different with verapamil, but the AsyI was significantly lower (P<0.05). CONCLUSIONS: Children with HCM show abnormalities of both global and regional LV diastolic function. In these patients, chronic administration of verapamil plays a crucial role in the improvement in global LV filling and, as a consequence, in clinical manifestations. The beneficial effects of verapamil seem to be related to a reduction in diastolic asynchrony more than to significant changes in diastolic velocities of the myocardial fibres.

Calcium Channel Blockers↗
PubMed1999

Arrhythmogenic substrate in young patients with repaired tetralogy of Fallot: role of an abnormal ventricular repolarization.

Ventricular repolarization analysis has been shown to be effective in the identification of electrical myocardial instability leading to ventricular arrhythmias. The aim of the present study was to examine ventricular repolarization time indexes, in terms of both absolute measures and dispersion across the myocardium, in young patients with repaired tetralogy of Fallot (41 pts; 28M/13F, age 11.7+/-3.6 years), assessing, furthermore, the possible influence of known negative prognostic factors relative to the surgical operation and residual haemodynamic abnormalities. The data of the study group were compared with those of 33 aged-matched asymptomatic control subjects (22M/11F, age 11.7+/-2.3 years). Ventricular depolarisation, as expressed by QRS duration, resulted significantly longer in total Fallot group than in the Control group (P<0.0001). Particularly, patients operated through a right ventricular approach showed higher values of QRS interval (P<0.0001) than those operated through a combined transatrial-transpulmonary approach. All the patients operated on for tetralogy of Fallot exhibit, with respect to control subjects, an inhomogeneous prolongation of ventricular repolarization across the myocardium, as showed by the significant increase in the absolute indexes of ventricular repolarization, JTc (P<0.001), QT (P<0.0001) and QTc (P<0.0001) with a concomitant prolongation of the indexes of dispersion of ventricular recovery time, QTcD (P<0.0001), JTcD (P<0.0001), 'adjusted' QTcD (P<0.001) and Tp-Te interval (P<0.0001). A temporal and regional variation in the ventricular repolarization across the myocardium in patients with repaired tetralogy of Fallot, could create the pathophysiological substrate for an increased cardiac electrical instability. The presence of negative prognostic factors, relative to the surgical intervention or residual haemodynamic abnormalities, even if not influencing the arrhythmic substrate, invariably present, could determine 'trigger' conditions essential for the development of ventricular arrhythmias.

Adolescent↗
PubMed1999

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.

Administration, Oral↗
PubMed1999

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.

Adolescent↗
PubMed1999

Left ventricular midwall mechanics in healthy children and adolescents.

The assessment of left ventricular function in pediatric age generally has been made by measuring the extent and velocity of fiber shortening at the endocardium and relating these parameters to systolic wall stress. It has been suggested from animal and human studies that this "endocardial method" can result in an overestimation of myocardial function when healthy hearts and those with hypertrophy are compared. Thus an assessment of left ventricular pump function and contractility that takes into account the epicardial migration of the midwall circumferential fibers during systole (midwall analysis) is warranted. Although the normal range for midwall indexes of left ventricular mechanics has been established in adult subjects, up to now it has not been studied in pediatric subjects. To establish normal values for left ventricular midwall mechanics, 70 healthy children ranging in age from 3 days to 18 years were evaluated with 2-dimensional and M-mode echocardiography. Midwall fractional shortening (FSmw), rate-corrected mean velocity of circumferential fiber shortening (VCFcmw), and the relation between these indexes and left ventricular end-systolic wall stress (ESS) were calculated separately for the children younger than 2 (group 1, 20 subjects) and older than 2 (group 2, 50 subjects) years of age. Group 1 had significantly higher FSmw and VCFcmw compared with group 2. An inverse linear relation between FSmw and ESS and between VCFcmw and ESS was found in both age groups. The y-intercept was higher in group 1, and the slope of the mean regression line was steeper than in group 2 for both the relationships, suggesting an age-dependent midwall left ventricular pump function and contractility. These normative data can be used to assess the left ventricular midwall mechanics in pediatric patients with pressure or volume overload.

Adolescent↗
PubMed1998

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.

Adolescent↗
PubMed1998

Prenatal diagnosis of 22q11 microdeletion in a fetus with a conotruncal heart defect.

A case of prenatal diagnosis of 22q11 microdeletion in a fetus with a conotruncal heart defect is described. This type of chromosomal aberration has been shown to be present in up to 30% of isolated conotruncal anomalies and in most cases of DiGeorge and velocardiofacial syndromes. The implications of such a diagnosis on prenatal counselling are discussed.

Amniocentesis↗
PubMed1998

[Dispersion of ventricular recovery time following surgery for tetralogy of Fallot: correlation with negative prognostic factors].

Malignant ventricular arrhythmias have been reported in patients with repaired tetralogy of Fallot. The aim of this study was to examine ventricular repolarization time indexes, in terms of both absolute measures and dispersion across the myocardium, in young patients operated on for tetralogy of Fallot (32 patients; 19 males and 13 females, mean age 11.1 +/- 3.4 years); these electrocardiographic parameters have been shown to be effective in the identification of electrical myocardial instability and hence of risk for ventricular arrhythmias too. The electrocardiographic data of the study group were compared with those of 22 age-matched asymptomatic control subjects (14 males and 8 females, mean age 12 +/- 1.5 years). Furthermore it has also been investigated the possible influence on ventricular repolarization of known negative prognostic factors relative to the surgical approach, age at intervention, and presence of pulmonary obstruction and/or regurgitation. No patients in the study group revealed at the Holter recordings and/or at the exercise test severe ventricular arrhythmias. From the analysis of ventricular depolarization, expressed by QRS duration, emerged that it resulted significantly longer in total Fallot group (p < 0.0001), and in each subgroup (p < 0.05) compared to the control group. Particularly, patients operated through a right ventricular approach showed higher values of QRS interval (p < 0.05) than those operated through combined transatrial-transpulmonary approach. All patients operated on for tetralogy of Fallot showed, compared to control subjects, a non homogeneous prolongation of ventricular repolarization across the myocardium, as confirmed by the significant increase in the absolute indexes of ventricular repolarization, JTc (p < 0.001), QT (p < 0.0001) and QTc (p < 0.0001) with a concomitant prolongation of the indexes of dispersion of ventricular recovery time, QTc dispersion (p < 0.0001), JTc dispersion (p < 0.0001), "adjusted" QTc dispersion (p < 0.05) and T peak-T end interval (p < 0.0001). The non homogeneous ventricular repolarization across the myocardium, preceding the development of arrhythmic events, could be the effect of the right ventricular morphological and functional changes of tetralogy of Fallot predisposing to the development of ventricular reentry tachyarrhythmias.

Adolescent↗
PubMed1996

Conotruncal anomalies in prenatal life.

This retrospective multicenter study represents an analysis of the intrauterine determinants of the prognosis for conotruncal anomalies. Data regarding reason for referral, presence of chromosomal or extracardiac anomalies, pregnancy and surgical outcome were recorded in 67 cases of conotruncal anomalies from three Italian referral units. Chromosomal aberrations effected 11 of the 60 (18.3%) fetuses in which a karyotype was available. Extra-cardiac malformations were present in 25/67 cases (37.3%). No chromosomal anomalies were present in fetuses with complete or corrected transposition of the great arteries. However, tetralogy of Fallot and double-outlet right ventricle were associated with chromosomal anomalies in 22% and 38% of cases, respectively, and with extracardiac anomalies in 45% and 46% of cases, respectively. Only 20 of the 67 (31%) cardiac malformations were associated with an abnormal four-chamber view. There were 28 (41.7%) terminations of pregnancy, six (8.9%) intrauterine deaths and 16 (23.8%) neonatal deaths. Seventeen neonates (25.3%) are currently alive, and 15 of these have undergone reparative surgery. The prognosis of conotruncal anomalies is poorer when the conditions is diagnosed in utero. This is mainly due to the frequent association with chromosomal and/or extracardiac anomalies, often leading to intrauterine or early neonatal death.

Chromosome Aberrations↗