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P Ragonese

Publications and source records attributed to P Ragonese.

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

[Mid-term clinical condition and prognosis in adrenergic ventricular tachycardia in children with apparently normal hearts].

INTRODUCTION: Ventricular tachycardia is the most common diagnosis among children with exercise or emotion-related syncope. The aim of the study was to assess the prognosis and the clinical course of children, without long QT syndrome, with exercise-related ventricular tachycardia and apparently normal heart. METHODS: Since January 1984, we studied 14 children (mean age 9.7 +/- 3.8 years) with exercise-related ventricular tachycardia, and, at the initial detection, without demonstrable heart disease, as assessed by clinical evaluation, electrocardiogram and mono-bidimensional echocardiogram. Six patients had exercise related syncope, 1 exercise intolerance and 7 were asymptomatic. All patients underwent exercise testing on treadmill and 24-hour ECG monitoring. All patients were treated with antiarrhythmic drugs. All patients were tested by exercise testing and 24 hour ECG monitoring, alternatively, every six months, during therapy or after complete wash-out of the drug used. RESULTS: Ventricular tachycardia, detected by exercise testing and Holter monitoring, was polymorphic in 4 symptomatic patients, monomorphic with left bundle branch block morphology and inferior axis in the others. The mean rate of monomorphic ventricular tachycardia was 224 +/- 35 bpm in the symptomatic children and 180 +/- 33 bpm in the others (p = 0.03). Successful chronic treatment was achieved with beta-blockers in 5 cases, propafenone in 6, sotalol in 2 and flecainide plus metoprolol in 1. During follow-up (6 +/- 2.7 years), 1 patient with polymorphic ventricular tachycardia, on therapy, suddenly died during exercise, the other symptomatic patients had no variation of their arrhythmia on routine tests, except 1 who, after propafenone was stopped, had ventricular fibrillation during exercise testing. Among the 7 asymptomatic patients, 5 had no evidence of ventricular tachycardia on routine test after 2 +/- 3 years; the others had no variation of their treatment. CONCLUSION: Exercise related ventricular tachycardia in children seems: 1) to have more severe prognosis if symptomatic or polymorphic; 2) mostly to arise from right ventricle; 3) to be successfully treated by antiarrhythmic drugs with beta-blocking activity.

Adolescent↗
PubMed1996

Reciprocating supraventricular tachycardia in children: low rate at rest as a major factor related to propensity to syncope during exercise.

Reciprocating supraventricular tachycardia may have several clinical presentations, with symptoms often more severe during exercise or emotional stress. This study shows by using transesophageal atrial pacing, the factors related to syncope during exercise. Between May 1989 and June 1994, transesophageal atrial pacing was performed at rest and during exercise in 75 children aged > 6 years with suspected or documented episodes of paroxysmal supraventricular tachycardia. Reciprocating supraventricular tachycardia could be induced both at rest and during exercise in 22 patients (8 girls, 14 boys; mean age 10.6 +/- 2.7 years, range 7 to 15 years) with ventriculoatrial interval < 70 msec in 11 patients and > 70 msec in 11. At rest, all patients had palpitations caused by the induction of tachycardia. After conversion to sinus rhythm, when tachycardia was induced during exercise, symptoms did not change in 14 patients (group A), whereas symptoms worsened (presyncope) in eight (group B). The statistical analysis showed a significant difference of mean reciprocating supraventricular tachycardia rate at rest between the two groups (group A, 211 +/- 23 beats/min; group B, 173 +/- 33 beats/min; p = 0.0057) and reciprocating supraventricular tachycardia rate variation from rest to exercise (group A, 62 +/- 18 beats/min; group B, 105 +/- 24 beats/min; p = 0.0001). These data suggest that children with low tachycardia rate during normal activities may have syncope more frequently, independently of the tachycardia rate during exercise or emotional stress.

Adolescent↗
PubMed1996

[Transcatheter radiofrequency ablation in supraventricular tachycardia in children: immediate results and mid-term follow-up].

OBJECTIVES: The purpose of this study was to evaluate the efficacy and safety of radiofrequency ablation of supraventricular tachycardias due to a reentry circuit in a group of closely followed-up pediatric patients. PATIENTS: Forty-six pediatric patients (mean age 12.6 years, range 3-18) underwent a total of 48 radiofrequency ablation procedures for reciprocating supraventricular tachycardia. Thirty-nine had an orthodromic reentry tachycardia, 6 an atrioventricular node reentry tachycardia and 1 a permanent junctional reciprocating tachycardia. METHODS: To ablate the overt accessory pathways, the Kent potential (K) was identified and then the shortest A-K, and delta wave-K intervals were measured. The shortest V-A interval was identified for those concealed. For the left-sided accessory pathways, we used the retrograde transaortic approach in 10 procedures and the transseptal approach in 18. Atrioventricular node reentry tachycardia was ablated at the site where the slow-pathway electrogram was recorded. Follow-up clinical data, electrocardiogram, 24-hours Holter monitoring and transesophageal atrial stimulation were obtained and evaluated. RESULTS: Early: We performed a total of 48 procedures. Among 41 procedures performed in the 39 patients with accessory pathway, 38 were successful (92,6%). Mean fluoroscopy time was 31 +/- 18 min. For left sided accessory pathways, mean fluoroscopy time of procedures with retrograde approach was 45 +/- 10 min and with transseptal 23 +/- 12 min (p < 0.01). Ablation of slow-pathway in patients with intranodal reentry tachycardia was successful in 3/6 cases (50%). The patient with permanent junctional reciprocating tachycardia was successfully ablated. Late: All patients are alive and none was lost during the follow-up after a mean time of 12.9 months (range 5-33). Success at last follow-up was 100% in patients with an accessory pathway and 33% in patients with atrioventricular node reentry. In patient with permanent junctional reciprocating tachycardia, the arrhythmia appeared again one month after the procedure, thus a second successful attempt was performed. COMPLICATIONS: Major complications (6,5%) including a right femoral vein thrombosis (one patient), an hematoma without pulse loss (one patient) and a non-sustained monomorphic ventricular tachycardia (one patient). CONCLUSIONS: Our data show high efficacy of radiofrequency ablation in pediatric patients with accessory pathways. The risks are low at follow-up evaluation, but might be helpful a longer-term follow-up in order to evaluate the risk of a long fluoroscopy time and the arrhythmogenic effect of the scar.

Adolescent↗
PubMed1996

[Functional evaluation by treadmill in children and adolescent following correction of Tetralogy of Fallot].

AIM OF THE STUDY: The Authors have examined 22 children (16m and 6f), mean age 9.64 +/- 2.63 years, range 5-15, after total correction for Tetralogy of Fallot, to evaluate the response of their cardiovascular apparatus during an exercise testing on treadmill (Bruce protocol). METHODS: Parameters examined: exercise duration, maximal heart rate (HR), maximal systolic blood pressure (max BP), non invasive cardiac output at rest and at the peak of exercise (CO), arterial oxygen saturation; lung function test at rest, echocardiogram and 24 hours Holter monitoring. CONTROL GROUP: 22 healthy peers, same gender, height and weight, not practising competitive sports. RESULTS: The exercise duration was significantly lower in the first group (77.8 +/- 11.8%; 86.5 +/- 8.2%; P = 0.006). Also max HR and max BP were significantly lower (max HR: 162 +/- 12 b/m'; 187 +/- 8 b/m'; P = 0.000), (max BP: 119 +/- 9 mm Hg; 126 +/- 12 mm Hg; P = 0.042). There were no differences for CO at rest (3.70 +/- 1.09 l/m'; 3.95 +/- 1.07 l/m'). In the first group, CO at peak of exercise was lower but not significantly (6.51 +/- 2.56 l/m'; 7.95 +/- 2.77 l/m'; NS). CONCLUSIONS: These results make more complete the not invasive functional evaluation for a better follow-up of these patients and a better choice for their physical activity.

Adolescent↗
PubMed1996

[Idiopathic recurrent ventricular tachycardia in children: characteristics and long-term prognosis].

BACKGROUND: The aim of this study was to assess the prognosis and the clinical course of incessant idiopathic ventricular tachycardia (VT) with left bundle branch morphology, in a group of 14 children consecutively evaluated in our institutions between 1983 and 1994. METHODS: Mean age of these patients was 8 +/- 2 years, and they were followed for 56 +/- 32 months. In all the children, VT was present for more than 80% of the day, in non sustained runs. The mean rate of VT was of 142 +/- 30 beats/min. Four children were symptomatic. The evaluation of these children was obtained by treadmill stress test (12/14), cardiac catheterization (13/14), electrophysiologic study (10/14), nuclear magnetic resonance (7/14), and serial echocardiographic and Holter examinations. RESULTS: Right ventricular dysplasia was suspected in 2 cases on the basis of nuclear magnetic resonance and angiographic data. In both these cases VT was not suppressed by exercise. Medical treatment was started in 9/14 patients (69%), it was completely effective in 4 (44%) and partially effective in 2 further cases (22%). Thirteen out of fourteen patients had a regular follow-up. No patient died. All patients remained asymptomatic and in 6 (46%) VT disappeared. In 4 of these last 6 patients therapy has been previously effective. Two children, one with right ventricle dysplasia, continue antiarrhythmic treatment. CONCLUSIONS: Incessant VT is well tolerated in pediatric age. The frequency of spontaneous remissions is relatively high (46% of cases). In few patients this arrhythmia is associated with evident cardiac abnormalities. In our opinion, medical treatment is necessary in symptomatic patients and in those with heart abnormalities.

Angiocardiography↗
PubMed1995

[Transesophageal atrial stimulation in the oral treatment of supraventricular reciprocal paroxysmal tachycardia in infants].

INTRODUCTION: The aim of the study was the evaluation of the usefulness of transesophageal atrial pacing in predicting chronic oral treatment efficacy of symptomatic reciprocating supraventricular tachycardia in infants and in avoiding the risk of very dangerous recurrences at home. METHODS: We studied 13 infants (11 males, 2 females, mean age 43 +/- 31 days) with symptomatic reciprocating supraventricular tachycardia and no structural heart disease. All patients had chronic oral therapy, using the drug effective in acute i.v. somministration. Each patient was discharged when supraventricular tachycardia was not inducible with transesophageal atrial pacing after 5 half-lives of the drug used in chronic oral treatment. All patients, every 6 months, were retested with transesophageal atrial pacing alternatively during chronic oral therapy and after complete wash out. Oral therapy was stopped in each patient when supraventricular tachycardia was not inducible after the wash out. RESULTS: The number of oral treatments tested for each patient were 2 +/- 1 (range 1-5). The number of transesophageal studies performed for each patient were 4 +/- 2 (range 3-7). No patient had symptomatic episodes of supraventricular tachycardia or needed to change therapy during the follow-up. The oral treatment was stopped after the twelfth month of life in 8 patients and after the twenty-fourth in 2 others without recurrences. CONCLUSION: Transesophageal atrial pacing seems to be useful in predicting accurately and rapidly the oral treatment efficacy of supraventricular tachycardia in infants. Our protocol seems to be effective to avoid dangerous recurrences of tachycardia and to decide when we can stop therapy without risk.

Administration, Oral↗
PubMed1994

Efficacy and safety of ventricular rate responsive pacing in children with complete atrioventricular block.

Single chamber rate responsive pacing offers many potential advantages over the more complex dual chamber atrial tracking pacing mode in children, and the preservation of atrioventricular synchrony could be unnecessary in selected groups of pediatric patients. Twenty-two pediatric patients (age range 9 months to 12 years; mean 6.5 years) had implantation of ventricular rate responsive (VVIR) pacemakers over a 2-year period. All patients had chronic third-degree atrioventricular block, and a normal ventricular function at rest. During the follow-up each patient underwent a 24-hour Holter monitoring, and ten performed a graded treadmill test in both ventricular fixed rate (VVI) and rate responsive (VVIR) pacing mode. Paced ventricular rates were found to be normal for age in all 22 patients; maximum rate did not reach the higher programmed rate during daily activities in any patient. Comparing the mean paced ventricular rate to the mean rates of blocked P waves, six patients showed a difference of more than 20 beats/min, which induced the pacemaker parameters to be reprogrammed. In all patients a significant correlation was found between variations of paced ventricular rate and variations of spontaneous blocked atrial rhythm (P < 0.05); this correlation persisted in the subsequent Holter controls in the ten patients with longer follow-up. Exercise tolerance resulted normal in the ten patients who performed a treadmill test either in VVIR or VVI mode, with increased maximal heart rates and maximal systolic blood pressure in VVIR mode (P < 0.0013). Rate responsive ventricular pacemakers seem to adequately respond to the physiological needs of daily life of this selected group of children requiring permanent pacing.

Atrial Function↗
PubMed1993

[The bidirectional cavo-pulmonary anastomosis: a clinico-functional assessment in a medium-term follow-up].

BACKGROUND: The bidirectional cavo-pulmonary anastomosis is a useful surgical procedure for patients with complex congenital heart disease characterized by univentricular physiology. This operation significantly increases effective pulmonary blood flow and rarely causes distortion of the main pulmonary arterial branches. The aim of this study was to evaluate the clinical and pathophysiologic consequences of bidirectional cavo-pulmonary anastomosis as well as the effectiveness of this surgical approach as a definitive palliation. METHODS: Clinical, hemodynamic and functional data of 12 patients who had undergone a bidirectional cavo-pulmonary anastomosis were reviewed. Each patient underwent clinical examination, chest x-ray, ambulatory EKG, bidimensional color-Doppler echocardiography, spirometric analysis, lung perfusion scintigraphy, cardiac catheterization and angiography, and stress test. Stress test data were compared to those obtained by a normal population of age-matched children. RESULTS: After a mean follow-up interval of 28 +/- 20 months all patients showed a good clinical condition. Improved oxygenation, exercise tolerance and growth velocity were noted in all patients. Only 34% of patients showed abnormalities of chest x-ray, 29% manifested significant arrhythmias during ambulatory EKG and 20% showed abnormal ventricular function echocardiographically. Spirometry was normal in all patients, while lung perfusion scintigraphy was constantly abnormal with right/left and upper/lower perfusion mismatch. At cardiac catheterization a reduction of end diastolic volume (from 106.9 +/- 50.6 to 67.3 +/- 41.6 ml, p < 0.05) and end systolic volume (from 58.0 +/- 27.9 to 32.5 +/- 33.5 ml, p < 0.05) was noted. The functional evaluation of these patients was highly abnormal due to an impaired response to effort as evidenced by work time (p < 0.0001 vs normal) and stress-induced cardiovascular modifications. CONCLUSIONS: On the basis of these findings, we suggest that: 1) bidirectional cavo-pulmonary anastomosis is useful as an intermediate step towards a Fontan procedure, as it improves the hemodynamic performance of the systemic ventricle; 2) conversely, bidirectional cavo-pulmonary anastomosis should not be considered a form of definitive palliation for complex congenital heart disease because in these patients the response to exercise remains unsatisfactory.

Adolescent↗
PubMed1992

Early identification of patients at risk for sinus node dysfunction after Mustard operation.

We studied 60 patients who had survived the Mustard procedure for transposition of the great arteries, performed between the ages of 2 days and 24 months (mean 4.51 +/- 3.79). All patients were given a postoperative 24-hour dynamic electrocardiogram at 15 days, 1 year and 3 years and then every 2 years. Those who were found to have sinus node dysfunction during follow-up, were given a dynamic electrocardiogram every 3-6 months. The average follow-up period was 38.7 +/- 19.8 months, median 36. Sinus node dysfunction was detected during follow-up in 20 patients (33.3% of the total), 8 of whom had had a pacemaker inserted. Risk factors for late development of sinus node dysfunction were found to include prolonged cross-clamping of the aorta during surgery (P = 0.003), especially over 50 minutes (relative risk 3.5:1), and the presence of even transient sinus node dysfunction after surgery (P = 0.006). These observations suggest, first, that sinus node dysfunction may develop after the Mustard operation as a combined effect of extensive atrial surgery and a long period of myocardial ischemia and, second, that the presence of the disease immediately after the operation sometimes indicates that it will recur or persist during follow-up.

Arrhythmias, Cardiac↗
PubMed1992

Left ventricular diastolic filling in type I diabetes mellitus: a pulsed Doppler echocardiographic study.

OBJECTIVES: Doppler echocardiography was used to assess left ventricular diastolic performance in young patients with type I diabetes mellitus and no clinical signs of heart disease. METHODS: The pattern of transmitral diastolic flow velocity was determined in 82 patients (56 men, 26 women; age 17.7 +/- 7.6) with type I diabetes mellitus and no heart disease. Maximal early diastolic flow velocity (E peak), maximal late diastolic velocity (A peak), the ratio of maximal flow velocity in late diastole to that in early diastole (A/E ratio) and the ratio of the time velocity integral of the diastole (1/3 FF) were measured in all 82 patients and repeated during exercise in 63 of them. Twenty healthy volunteers served as controls. RESULTS: Mean values of the Doppler indexes were not significantly different between the patients and the 20 controls, but diabetic patients with microvascular complications showed patterns of left ventricular diastolic flow velocity which suggested altered diastolic performance, namely lower E peak velocity, higher A peak velocity, raised A/E ratio and reduced 1/3 FF. Among the 63 examined during exercise, different diastolic flow patterns in response to effort made it possible to identify 15 patients with a high rate of autonomic dysfunction, indicating probable impairment of diastolic function and a need for close follow-up. CONCLUSION: Diastolic abnormalities may occur in young diabetic patients without evidence of heart disease and suggest Doppler evaluation is a sensitive method for identifying patients at potential risk of developing clinical heart disease.

Adolescent↗
PubMed1991

Oral propafenone therapy for children with arrhythmias: efficacy and adverse effects in midterm follow-up.

The use of oral propafenone was assessed in 57 children. Mean age was 4.8 +/- 5.2 years (range 1 day to 17 years). Twenty-three patients were less than 1 year of age (40%) and 10 were less than 1 month of age (18%). Arrhythmias included supraventricular tachycardia in 32 patients (57%), atrial flutter in six (10%), and ventricular tachycardia in 19 (33%). Cardiac diagnoses included: an otherwise normal heart in 30 (53%); unoperated congenital heart defect in 11 (19%); cardiomyopathy in nine (16%); and an operated congenital heart defect in seven (12%). Mean dose of propafenone was 13.1 mg/kg/day (range 8 to 15). Success (assessed by relief of symptoms and serial 24-hour ECGs) was achieved in 16 of 32 patients with supraventricular tachycardia (50%), three of six with atrial flutter (50%), and 8 of 19 with ventricular tachycardia (42%). Drug efficacy in patients with and without organic heart disease was 30% (8 of 27) and 63% (19 of 30), respectively (p less than 0.05). Mean duration of therapy in patients in whom the drug was effective was 22.9 +/- 13.2 months (range 6 to 60). Growth was unimpaired in all patients. A neonate with nonsustained monomorphic ventricular tachycardia had sustained ventricular tachycardia during the second day of propafenone therapy at a dose of 13 mg/kg/day. Sustained ventricular tachycardia disappeared when the drug was discontinued. Another patient had an asymptomatic and transient increase in the glutamic pyruvic transaminase level. No adverse hemodynamic effects were observed. In conclusion, propafenone is an effective antiarrhythmic drug in children with normal hearts; it is less effective in patients with heart disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Oral↗
PubMed1990

Usefulness of left and right oblique subcostal view in the echo-Doppler investigation of pulmonary arterial blood flow in patients with chronic obstructive pulmonary disease. The subxiphoid view in the echo-Doppler evaluation of pulmonary blood flow.

Fifty-nine adult patients with chronic obstructive pulmonary disease (COPD) underwent Doppler and two-dimensional echocardiographic examination to determine the variability of pulmonary arterial blood flow (PABF) from multiple views. Measurement of peak flow velocity (PFV), acceleration time (AT), right ventricular ejection time (RVET), and pulmonary arterial diameter (PAD) was possible in 52 patients (88 percent) by left oblique subcostal view (LOSV), in 38 patients (64.4 percent) by right oblique subcostal view (ROSV), and in only 12 patients (20.3 percent) by short axis parasternal view (SAPV) (p less than 0.05). Overall, PABF was measured in 55 patients (93.2 percent). The LOSV gave consistently higher values of PVF than those obtained either by ROSV (p less than 0.05) or by SAPV (p less than 0.05). We conclude that LOSV and ROSV allow measurement of PABF in the majority of patients with COPD.

Aged↗
PubMed1985

Effect of hypothyroidism on the labeling of the various RNA species in developing rat brain.

The effect of hypothyroidism on the vitro incorporation of [3H]uridine into different RNA species in tissue slices of rat cerebral hemispheres at 5, 10, 15, and 21 days of age has been investigated. Gel electrophoresis analysis of total, nuclear and microsomal RNA was also accomplished. The results obtained indicate that RNA labeling is differently influenced by hypothyroidism at the various ages examined. RNA labeling is not significantly affected at 5 days of age while at later ages and especially at 21 days it is higher in hypothyroid rats compared to the controls. Moreover distinct differences at the various ages in the transport of newly synthesized RNA from the nucleus to the cytoplasm in the two groups of animals were found. These results are in agreement with the hypothesis that thyroid hormone deficiency causes a delay of the processes of cell proliferation and differentiation in developing rat brain.

Age Factors↗
PubMed1983

Post-translational changes of chromosomal proteins in rat cerebellum during postnatal development.

Acetylation, phosphorylation and methylation of nuclear proteins in rat cerebellum at 10 and 30 days of age were investigated in vitro. Isolated nuclei were incubated in the presence of [1-14C]acetyl CoA, S-adenosyl [methyl-3H]methionine and [gamma-32P]ATP and then separated into histones and non histone proteins (NHP), which were further fractionated by polyacrylamide gel electrophoresis. The results obtained indicate that acetylation, phosphorylation and methylation of both basic and acidic proteins decrease from 10 to 30 days of age. Electrophoretic analysis of histones shows that the decrease mainly concerns H1, H3, and H2b fractions. The H3 fraction is always more labeled than the other fractions and shows the major changes during postnatal development. Phosphorylation of H2a and H4 fractions increases from 10 to 30 days of age, whereas acetylation and methylation of these fractions do not show significant changes from 10 to 30 days. The densitometric and radioactive patterns of NHP show considerable changes between 10 and 30 days, especially in the high molecular weight region. The incorporation of 14C-acetyl and 3H-methyl groups and of 32P phosphate appears to be generalized throughout the molecular weight range and decreases from 10 to 30 days of age. The methylation of an as yet unidentified protein with a molecular weight of approximately 110,000 daltons occurred at both ages.

Acetylation↗