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G Stellin

Publications and source records attributed to G Stellin.

At least 37 records · Page 2Linked to original sources
PubMed1997

Echocardiographic evaluation of systolic and diastolic left ventricular function following arterial switch operation in the neonatal period for transposition of the great arteries. Midterm results.

BACKGROUND: Neonatal arterial one-stage switch operation (ASO) for transposition of the great arteries (TGA) is currently the procedure of choice for TGA. There is a potential risk of myocardial damage related to coronary artery reimplantation and sudden pressure overload imposed on the left ventricle after discontinuation of the cardiopulmonary bypass. OBJECTIVES: This study was carried out in order to evaluate left ventricular systolic and diastolic function in children following ASO. METHODS: We studied 32 children (22 M, 10 F), mean age 23.7 +/- 24.6 months (range 0.5-97.2) following ASO, without any hemodynamically significant residual stenosis by 2D- and Doppler-echocardiography. Twenty-five had TGA with intact ventricular septum and 7 with ventricular septal defect. Mean age at time of one-stage repair was 8.9 +/- 6.9 days (range 2-30) and the mean time of follow-up 23.5 +/- 24.6 months (range 0.3-96). At the time of evaluation all the children were asymptomatic. Regional wall motion of the left ventricle was assessed by 2D-echo. Volumes, mass index, M/V ratio, afterload, systolic function (FS% and VCFc), contractility (stress-velocity SVI and stress-shortening SSI relations) and preload (functional preload index FPI = SSI-SVI) of the left ventricle were determined by m-mode echo together with non-invasive blood pressure monitoring. Left ventricular diastolic function was determined by PW Doppler of transmitral flow. All parameters were compared with those of 32 normal controls matched for age, sex and body surface area. RESULTS: Left ventricular regional wall motion was normal in all but 5 cases who showed a slight reduction of the septal systolic motion. Volumes and EF% did not differ in post-ASO group vs controls. There was a small increase of the mass index in the post-ASO group vs controls (62.8 +/- 14.1 vs 56.2 +/- 6.5 g/m2; p = 0.02) and the M/V ratio did not differ. FS% and VCFc were not different between the 2 groups. Peak and end-systolic meridional stress also did not differ in the 2 groups. A normal contractile state was present in the post-ASO group. The preload was slightly reduced in the post-ASO children (FPI -0.6 +/- 0.94 vs 0.07 +/- 0.63; p = 0.001). Parameters of left ventricular diastolic function were not significantly different between the 2 groups. CONCLUSIONS: In conclusion in children undergoing neonatal ASO for TGA with intact septum or ventricular septal defect, evaluated after a mean post-surgical follow-up of 2 years, systolic and diastolic performance of the left ventricle was normal. Regional wall motion abnormalities with slightly reduced septal motion were detected in 5 cases. The reason for the small increase in mass index is unknown. The slight reduction of the preload is related to the routine drug therapy in the patients studied early after surgical repair.

Child, Preschool↗
PubMed1995

Repair of tetralogy of Fallot in the first six months of life: transatrial versus transventricular approach.

BACKGROUND: This report describes our experience with primary correction of tetralogy of Fallot in infants. METHODS: Fifty-one consecutive infants younger than 6 months underwent primary correction of tetralogy of Fallot between January 1978 and October 1994. Mean age at repair was 4.2 months. Four were neonates. Correction was accomplished through a right ventriculotomy in the first consecutive 22 patients (43%; group A); since 1991, a combined transatrial-transpulmonary approach was used in 29 consecutive patients (57%; group B). A transannular patch was necessary in 33 infants (65%) 16 of group A (73%) and 17 of group B (59%). RESULTS: There was one early death from possible left anterior descending coronary artery distortion in group A and no deaths in group B. Two patients required early reoperation for systemic-to-pulmonary artery collateral ligation (postoperative day 6) and permanent pacemaker implantation (postoperative day 30). There were no late deaths. All 50 survivors are currently asymptomatic and in New York Heart Association class I. Three patients required late reoperations 36 months, 30 months, and 13 months after repair for (1) subaortic stenosis and dysfunctioning dysplastic mitral valve, (2) residual pulmonary artery branch stenosis, and (3) residual right ventricular outflow obstruction. Four patients underwent balloon dilation and stent insertion (1 patient) for peripheral pulmonary artery stenosis 1.5 year to 12 years (mean, 5 years) after initial repair. Actuarial freedom from need for reintervention at 4 years was 78.4% in group A and 85.7% in group B. Two-dimensional and Doppler echocardiographic follow-up studies showed a residual mild to moderate pulmonary artery branch stenosis in 4 patients in group A, and a recurrent subaortic stenosis in 1 patient in group A. Right ventricular peak systolic pressure was less than 40 mm hg in all but 3 asymptomatic patients who had a residual pulmonary artery branch stenosis. Right ventricular end-systolic and end-diastolic volumes showed larger volumes and reduced ejection fraction in group A compared with group B. CONCLUSIONS: This limited experience with repair of tetralogy of Fallot in patients less than 6 months of age demonstrates that the transatrial-transventricular approach is possible in neonates and young infants with a very low mortality and morbidity and also a low incidence of residual lesions. Follow-up echocardiographic data suggest that right ventricular function is better preserved in those patients who underwent the transatrial-transpulmonary repair.

Cardiac Surgical Procedures↗
PubMed1995

Left atrioventricular valve incompetence after repair of common atrioventricular canal defects.

BACKGROUND: Reoperation rate for residual atrioventricular (AV) valve regurgitation after repair of common atrioventricular canal defect (AVCD) is currently between 5% and 10%. This retrospective analysis evaluates the impact of AV valve anatomy, age at repair, and surgical technique on postoperative AV valve incompetence. METHODS: Between January 1982 and July 1994, 205 patients with common AVCD underwent surgical repair at our institution. A complete form with common atrioventricular orifice (CCAVCD) was present in 81 patients. One hundred twenty-four had separate AV valves and orifices; 22 of these had a restrictive ventricular septal defect component. Preoperative moderate to severe AV valve regurgitation (AVVR) was present in 74 (36%), with a lower incidence in the CCAVCD group (20/81, 25%) versus the transitional (8/22, 36%) or the partial forms (46/102, 45%) (p = 0.02). The incidence was 12.5% (3/24) for CCAVCD patients less than 4 months of age (p = 0.02). Repair of the left AV valve was performed according to the trifoliate approach in most cases (142/205, 70%). Follow-up was 98% complete. RESULTS: By Kaplan-Meier analysis, survival at 12.3 years was 97.8% +/- 1% in partial AVCD, 95.4% +/- 4% in transitional AVCD, and 73.2% +/- 5% in CCAVCD (median follow-up, 60 months). Freedom from reoperation at 12.3 years was 93.5% +/- 2% for partial AVCD, 76.9 +/- 9% for the transitional form, and 68.3% +/- 5% for CCAVCD: Postoperative moderate to severe AVVR occurred in 42 patients (21%), with lower incidence for CCAVCD (10/81, 12.5%) versus transitional AVCD (8/22, 36%) and partial AVCD (24/102, 24%) (p = 0.02). Postoperative moderate AVVR was found in only 1 patient with CCAVCD less than 4 months of age (p < 0.01). Nine patients (5%) underwent reoperation for residual postoperative AVVR Valve repair was performed in all with no operative death. By Cox proportional risk multivariate analysis, preoperative AVVR and double orifice "mitral" valve were associated with increased risk of postoperative left AVVR (p < 0.01), whereas a bifoliate approach appeared to reduce the risk of this event in partial AVCD (p = 0.03). CONCLUSIONS: Postoperative AVVR is related to the type of anatomy of the AV valve, to the age at repair, and to the surgical technique employed. Residual AVVR can still be corrected with conservative techniques at low mortality rates. Early repair of common AVCD is associated with a lower incidence of preoperative and postoperative AVVR in CCAVCD and seems to prevent progression of annular dilation and preoperative AVVR in partial AVCD.

Aortic Valve Insufficiency↗
PubMed1993

Rat jejunal absorptive function after intestinal transplantation. Effects of extrinsic denervation.

Jejunal absorptive function was evaluated following small intestinal transplantation to determine the effects of extrinsic denervation. In particular, water and sodium absorption were measured following transplantation (denervated) and compared to a control group (Thiry-Vella). Water flow was initially secretory two days after transplantation (-41 +/- 27 microliters/min/g dry tissue weight) but became absorptive at day 8 (25 +/- 25). Water flow in the Thiry-Vella group was not significantly different (P > 0.05) from the transplant group at days 8 (17 +/- 7) and 10 (47 +/- 42). Sodium flows were also initially secretory in the transplant group and became absorptive. This study refutes previous claims that small bowel transplants have a deficiency of water absorption due to extrinsic denervation of the bowel and suggests normal absorptive function of water, electrolytes, and protein.

Alanine↗
PubMed1993

Application of fresh and cryopreserved homografts harvested from transplant patients for correction of complex congenital heart disease.

In recent years, the use of homograft tissue in cardiac surgery has increased so that supply is limited. Since October 1990, aortic and/or pulmonary valves were collected from 17 transplant recipients at the Department of Cardiovascular Surgery of the University of Padova Medical School (11 male, 6 female, mean age 43.4 years, range 11 months to 61 years). The indications for transplant were dilated cardiomyopathy in 7, and end-stage ischemic heart disease in the remaining 10 patients. Twelve such valves have been subsequently reimplanted either as fresh or as cryopreserved valved homografts in the repair of different forms of congenital heart disease, by means of different tailoring techniques (7 male, 5 female; mean age 4.8 years [range 1 day to 18 years]; transposition of the great arteries = 5 cases; tetralogy of Fallot = 3 cases; hypoplastic left heart syndrome = 2 cases; double outlet right ventricle = 1 case; truncus arteriosus = 1 case). Overall, early mortality was 25%. None of these deaths could be related to the use of homografts. There have been no instances of valve related complications among nine patients surviving surgery at a mean follow-up of 11 months. All patients having heart explanted should be regarded as potential sources for aortic and pulmonary homografts.

Adolescent↗
PubMed1993

Pulmonary atresia, intact ventricular septum, and Ebstein anomaly of the tricuspid valve. Anatomic and surgical considerations.

Pulmonary atresia with intact ventricular septum is a disorder that involves the whole right ventricle. An associated Ebstein deformity of the tricuspid valve is found in 10% of the cases, further complicating the anatomy and the function of the right ventricle. From January 1966 to December 1990, pulmonary atresia, intact ventricular septum, and Ebstein deformity of the tricuspid valve were observed in 11 cases in our institution; four of them were necropsy findings and the remaining seven were patients treated surgically. Of the latter, two were boys and five were girls (age range 1 day to 18 days). Two patients were managed by pulmonary valvotomy, three by systemic-pulmonary artery shunt, and two had a combination of the two. Operative mortality was 57%. Eight hearts were available for morphologic study. All had viscero-atrial situs solitus, D-loop ventricular structure, and normally related great arteries. A correlation between the degree of tricuspid valve dysplasia and right ventricular cavity size was observed in all. Furthermore, in five cases the anterior leaflet of the tricuspid valve obstructed the right ventricle at the ostium infundibuli level. In two of our surgical patients, a protruding anterior tricuspid valve leaflet was identified and excised and both patients survived. Ebstein anomaly of the tricuspid valve further complicates surgical management and outcome of pulmonary atresia and intact ventricular septum. Potential obstruction at the ostium infundibuli level should always be considered during repair. Various degrees of right ventricular inlet dysplasia, always present in this complex, may contraindicate an anatomic correction. In these cases a modified Fontan-type procedure should be considered as a valid surgical option.

Abnormalities, Multiple↗
PubMed1992

Annular enlargement during aortic valve replacement: preliminary results with a simplified technique.

A simplified technique has been used to enlarge the aortic annulus in a series of 13 patients undergoing aortic valve replacement. The procedure basically consists of extending the aortotomy incision into the aortic annulus by dividing the commissure between the left and noncoronary sinuses, without involving the anterior mitral leaflet. Wide opening of the commissure is obtained and the resulting defect is closed, preferably using a patch of bovine pericardium sutured to the mitral annulus and aortic wall. This technique is simple, reproducible, avoids opening of the left atrium (reducing the potential bleeding sites), allows insertion of a prosthesis at least two sizes larger than the original annulus, and is also applicable in cases of mitral-aortic valve replacement. Our preliminary results are satisfactory and seem to demonstrate that in many patients, even in the young age group, more complex procedures are often unnecessary when enlargement of the aortic annulus is required.

Adult↗
PubMed1991

Electrical instability in patients undergoing surgery for atrioventricular septal defect.

Postoperative 24-hour Holter monitoring was performed in 106 patients with atrioventricular septal defect in order to identify the incidence of atrial and ventricular arrhythmias. Of the patients, 72 had separate atrioventricular orifices, including 13 with a small ventricular component to the defect, and 34 patients had a common atrioventricular orifice. Two groups of abnormal patients were found. First, patients with good electrical stability characterized by isolated atrial (9 patients) and ventricular (25 patients) extrasystoles falling in classes I and II of Lown. Second, patients with marked electrical instability characterized in one patient by repetitive atrial extrasystoles, in another by atrial flutter, in 2 by polymorphic ventricular extrasystole and in 8 by couplets or triplets. Electrical instability in individual patients was then compared, by means of logistic regression analysis, with operative, surgical and postoperative variables. There was no incidence of sudden death in our series. After surgical repair, ventricular arrhythmias were more frequent than atrial arrhythmias (33% vs. 10%) and were unrelated to the type of atrioventricular septal defect. Cardiac electrical instability after operation was significantly related to larger operative body size, higher postoperative end diastolic diameter of the right ventricle, larger size of the ventricular septal defect, coexistence of postoperative right bundle branch block and left anterior hemiblock. Conversely, the risk of arrhythmias was reduced by more recent operative data and by greater shortening fraction of the left ventricle.

Arrhythmias, Cardiac↗
PubMed1991

Survival in trauma victims with pulmonary contusion.

The author evaluated 203 consecutive patients with severe chest trauma admitted to the trauma center between 1985 and 1989. The goal was to identify risk factors that play a significant role in mortality of patients with pulmonary contusion. There were 160 men and 43 women. The average was 33 years (range 2 to 92 years); 178 patients were younger than 60 years and 25 were older. There were 183 motor vehicle or motorcycle accidents, five gun shot wounds, one stab wound, five falls from height, three industrial accidents, one altercation, and five other undetermined causes. One hundred and fifty-nine patients survived; 44 died (22%). Their injury severity scores averaged 27 (range 9 to 59) for the survivors and 43.5 (range 17 to 75) for the nonsurvivors. Fifty-seven per cent of the patients required mechanical ventilation. The average time on the ventilator was 4.4 days (range 1 to 47 days) for the survivors and 14.2 days for the nonsurvivors (range 1 to 126 days). Of the patients less than 60 years old, 34 (20%) died, but 10 (40%) of the 25 patients older than 60 years died. Average blood loss was 1,047 cc (range 0 to 14,300 cc), but the difference was not statistically significant between survivors and nonsurvivors in the authors' series. Injuries to the central nervous system were present in 80 (40%) of the patients and were associated with death in 30 (68%) of the cases. Age, severity of injury, associated head trauma, and shock were the most important factors affecting survival in the authors' patients with pulmonary contusion.

Adolescent↗
PubMed1991

[Congenital malformations of the mitral valve: clinical and morphological aspects].

The clinical, anatomic and functional features of 23 pts with congenital mitral valve malformation, seen at the University of Padua over a period of 10 years, are described. All pts underwent hemodynamic investigation and echo-Doppler evaluation. Diagnosis was confirmed at surgery in 17 cases, and at necropsy in six. In 9 pts mitral anomalies determined prevalent stenosis; the remaining 16 pts had moderate to severe mitral regurgitation. Associated cardiac malformations were present in 19 cases (82.6%). The clinical presentation occurred earlier in pts with mitral stenosis (16.9 months vs 6.55 years). The morphologic and echocardiographic features of each malformation are described. The term "valve dysplasia", as proposed by Becker et al to define the non-Ebstein malformations of the tricuspid valve, is herein applied to the congenital anomalies of the mitral valve in order to obtain a uniform and homogeneous approach to this vast spectrum of malformations.

Adolescent↗
PubMed1991

Early screening and treatment of "silent" patent ductus arteriosus in prematures with RDS.

From January 1987 to December 1989, prematures with RDS weighing 1750 g or less admitted to the Neonatal Intensive Care Unite (NICU) were submitted from the third postnatal day to serial two-dimensional and pulsed Doppler (ATL MK 600) echocardiographic evaluation for "silent" patent ductus arteriosus (PDA). PDA was diagnosed in 36/175 prematures with RDS (20.5%). Thirty patients had indomethacin treatment and the PDA closed completely in 27 (90%); five needed a second course of indomethacin, that was effective in two (40%). Four RDS patients (4/36-11%) already weaned from the respirator, needed supplemental oxygen. The three non-responders and six other prematures with counterindications to the drug underwent surgical ligation (25%). As historical control, we retrospectively evaluated the population of preterm infants with RDS weighing less than or equal to 1750 g treated for hemodynamically significant PDA during three previous years before the screening protocol; in this group the echocardiographic and Doppler evaluations were done when congestive heart failure and pulmonary edema were clinically evident. In comparison, we found a reduced incidence of prematures with RDS treated for PDA, 7/120 (5.8%) a higher age at medical treatment (9 +/- 1.4 vs 4.4 - 2.3 days) and a larger prevalence of patients underwent ductal ligation (71.4%). These data show that early screening and treatment of "silent" PDA may result advantageous to improve the efficacy (90%) of indomethacin, in a critical time for the recovery of RDS, and furthermore decreasing the need of surgical ligation.

Birth Weight↗
PubMed1991

The surgical anatomy of double-outlet right ventricle with concordant atrioventricular connection and noncommitted ventricular septal defect.

In describing hearts with double-outlet right ventricle, we have had problems with how best to use the term noncommitted as applied to the ventricular septal defect. We reviewed, therefore, 63 hearts with double-outlet right ventricle in the setting of usual atrial arrangement and a concordant atrioventricular connection. From these, 18 hearts with potentially noncommitted defects were identified and studied in detail. The defect was unequivocally remote from the ventricular outflow tracts in 16 of these hearts, being perimembranous with excavation to open into the inlet of the right ventricle in 12, two of these also having straddling of an atrioventricular valve. One heart had a muscular defect situated in the inlet part of the muscular septum, whereas the defect was the ventricular component of an atrioventricular septal defect in the other three. In the remaining two hearts the defect was anatomically juxtaposed to a subarterial outlet. The pathway to the outflow tract, however, was obstructed by leaflets of a straddling valve. Our study shows, therefore, the need to distinguish between anatomic "commitment" of the defect from the problems in terms of commitment that may confront the surgeon in the operating room. Not only does the distance between the interventricular communication and one of the subarterial outflow tract need to be assessed (the anatomic commitment), but also the presence and nature of any intervening extraneous tissues (the surgical commitment) requires assessment.

Double Outlet Right Ventricle↗
PubMed1990

Influence of prosthetic design on durability of the Liotta porcine valve in the mitral position.

From March 1979 to December 1984, the Liotta low-profile porcine bioprosthesis was employed for mitral valve replacement in 71 patients to avoid potential left ventricle-prosthesis mismatch occasionally observed with the standard, high-profile, Hancock porcine xenograft. Follow-up of 61 operative survivors showed at 10 years an actuarial survival of 67% +/- 7%, freedom from thromboemboli of 96% +/- 2%, freedom from structural deterioration of 63% +/- 11% and freedom from all Liotta bioprosthesis-related complications of 53% +/- 10%. Complications related to excessive protrusion of the stent into the left ventricular cavity were eliminated with the Liotta bioprosthesis; the peculiar stent configuration, however, was responsible for an increased rate of structural deterioration requiring reoperation in 10 patients (2.8% +/- 0.9%/patient-year) at a mean interval of 76 +/- 18 months after mitral valve replacement (range, 45 to 106 months). Common findings in all explants were cusp prolapse, cusp tears, and commissural rupture related to various degrees of tissue calcification, constantly leading to severe prosthetic incompetence. As also shown experimentally, such structural changes have been attributed to increased systolic stresses on the closed cusps, favored by excessive reduction of the stent height. Our experience shows that the Liotta bioprosthesis used for mitral valve replacement does not provide any clear-cut advantage over standard porcine bioprostheses and that its long-term durability appears affected by the unique prosthetic design.

Adult↗
PubMed1990

Early and late results after repair of tetralogy of Fallot.

Between January 1, 1975, and December 31, 1988, 233 patients were operated on for correction of tetralogy of Fallot (TOF). Mean follow-up was 13.9 years (median 7.65 years) and was 99.6% complete. Actuarial survival was 84 +/- 3%. The risk of death decreased gradually to a constant rate of 0.00034 deaths/month by the 6th postoperative month. There were 22 early deaths, due mostly to Low Output Syndrome. The principal incremental risk factor was the postrepair ventricular pressure ratio (PRV/LV) (P less than 0.0001). Other factors were: patent ductus arteriosus (PDA; P = 0.02), other associated anomalies (P = 0.005), higher preoperative hemoglobin levels (P = 0.06) and use of transannular patches (P = 0.02). The operative risk was significantly reduced by a recent operative date (P = 0.01) and by an older age at operation (P = 0.12). Among 8 late deaths, 2 were unrelated to the cardiac condition, 2 occurred suddenly, 3 were due to congestive heart failure and the last was due to reoperation for patch endocarditis. The risk of late death was significantly higher in patients operated on at an older age (P = 0.04). There were 10 open heart reoperations: 5 for patch dehiscence, 4 for residual pulmonary stenosis and 1 for residual atrial septal defect. The reoperation-free actuarial survival was 82 +/- 3%. With the present operative standards, the parametric operative risk of an average patient with simple TOF (hemoglobin = 12 g, PRV/LV = 0.5) is 0.7%. Where the TOF is severely cyanotic (hemoglobin = 25 g) and the pulmonary arteries are severely restricted, the average mortality is 30%.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1990

Anomalies of the systemic venous return: a review.

Congenital anomalies of the systemic venous connection to the heart represent a rather wide and heterogeneous group of malformations, whose physiological consequences may vary from nil to the most severe form of systemic arterial desaturation. The malformations may be summarized as follows: (1) Left superior vena cava connected to the coronary sinus, interrupted inferior vena cava and absent right superior vena cava that do not indicate surgical repair 'per se', but require some technical attention during open heart surgery performed for other anomalies; (2) Left superior vena cava connected to the left atrium, due to incorporation of the coronary sinus into the left atrial cavity, resulting in a right-to-left-shunt; (3) Right superior vena cava or inferior vena cava draining into the left atrium, both are extremely rare and require treatment for the ensuing right-to-left shunt; (4) Total anomalous systemic venous connection to the left atrium, usually combined with atrial isomerism and other very complex heart malformations; (5) Cor triatriatum dexter, which has been frequently diagnosed as an anomalous venous connection for its similar hemodynamic consequences. Such anomalies are reviewed with particular respect to their surgical implications.

Cor Triatriatum↗
PubMed1990

Long-term performance of the Hancock porcine bioprosthesis in the tricuspid position. A review of forty-five patients with fourteen-year follow-up.

Because little information is available regarding the clinical performance of the Hancock porcine bioprosthesis (Johnson & Johnson Cardiovascular, King of Prussia, Pa.) implanted in the tricuspid position, we reviewed the long-term follow-up of patients who had tricuspid valve replacement with this device. From March 1970 to December 1983, 45 patients had tricuspid valve replacement, either isolated (seven patients) or combined with replacement of other valves (38 patients) by means of a standard, glutaraldehyde-preserved Hancock porcine bioprosthesis. Follow-up ranged from 0.2 to 14.7 years (mean, 7.6 +/- 3.6 years) and was complete. The late mortality rate was 6.6% +/- 1.6%/pt-yr and the actuarial survival rate at 14 years was 23% +/- 9%. Reoperation because of structural deterioration of the tricuspid, the mitral, or both bioprostheses was performed in nine patients (3.7% +/- 1.2%/pt-yr) from 40 to 177 months (mean, 112 +/- 43 months) and resulted in no deaths. Actuarial freedom from structural deterioration of a Hancock tricuspid porcine bioprosthesis at 14 years is 68% +/- 13%. Morphologic examination of explanted porcine bioprostheses showed that those implanted in the tricuspid position had lower degrees of calcification and less severe structural changes than those simultaneously explanted from the mitral position. We conclude that the Hancock porcine bioprosthesis has an acceptable long-term durability and satisfactory performance after tricuspid valve replacement, and we continue to favor its use in the tricuspid position even in association with mechanical prostheses in the left side of the heart.

Adolescent↗