Torsade de pointes ventricular tachycardia during low dose intermittent dobutamine treatment in a patient with dilated cardiomyopathy and congestive heart failure.

The authors describe the case of a 56-year-old woman with chronic, severe heart failure secondary to dilated cardiomyopathy and absence of significant ventricular arrhythmias who developed QT prolongation and torsade de pointes ventricular tachycardia during one cycle of intermittent low dose (2.5 mcg/kg per min) dobutamine. This report of torsade de pointes ventricular tachycardia during intermittent dobutamine supports the hypothesis that unpredictable fatal arrhythmias may occur even with low doses and in patients with no history of significant rhythm disturbances. The mechanisms of proarrhythmic effects of Dubutamine are discussed.

Incessant ventricular tachycardia early after acute myocardial infarction: efficacy of radiofrequency catheter ablation but not of optimal coronary revascularization.

Incessant ventricular tachycardia is an arrhythmia refractory to conventional antiarrhythmic treatment. We describe the case of 55-year-old man who presented incessant ventricular tachycardia in the early post-acute phase of myocardial infarction. Optimal coronary revascularization was not effective, but radiofrequency catheter ablation was able to eliminate the anatomic substrate and clinical arrhythmic recurrence.

Ventricular late potentials, interstitial fibrosis, and right ventricular function in patients with ventricular tachycardia and normal left ventricular function.

We examined 40 patients with ventricular tachycardia (VT) and no evidence of heart disease, and found a 50% prevalence of ventricular late potentials (VLPs) on the signal-averaged electrocardiogram. This finding was associated with a significantly higher content of fibrous tissue on endomyocardial biopsy and a lower right ventricular ejection fraction. Thus, VLPs are frequently found in idiopathic VT, are a marker for subclinical anatomic and functional abnormalities of the right ventricle, and may be associated with a worse outcome.

Detectable serum troponin I in patients with heart failure of nonmyocardial ischemic origin.

Cardiac troponin I, a specific and sensitive marker of myocardial damage, was detected in the blood of 6 of 26 patients studied in our Heart Failure Clinic. In these patients functional class, ventricular function, and prognosis were significantly worse than in those without detectable troponin I. This study suggests that troponin I may represent the biochemical marker of myocardial damage occurring in severe heart failure.

[Troponin T, Troponin I and CK-MB (mass) in the detection of periprocedural myocardial damage after coronary angioplasty]. / Troponina T, troponina I e CK-MB (massa) nel riconoscimento del danno miocardico periprocedurale dopo angioplastica coronarica.

The development of methods for the detection of circulating CK-MB mass, cardiac troponin T (cTn-T) and troponin I (cTn-I) has increased the diagnostic potential in the identification of myocardial damage. Coronary angioplasty (PTCA) represents a widely accepted revascularization procedure and a clinical model of induced ischemia. Using these new biochemical markers, we evaluated the incidence and the clinico-procedural correlates of minor myocardial damage (MMD) in a series of patients treated with PTCA in our Department. In 57 consecutive patients (75% males; mean age 58 years; range 35-80) undergoing elective PTCA from March 1 to June 30, 1995, serum levels of CK-MB mass, cTn-T and cTn-I were measured at baseline and at 6, 12 and 24 hours after the procedure. Seventy-eight coronary stenoses were dilated (mean 1.4 lesion/patient), 17 of these were in infarct-related vessels; 8 were total occlusions and 2 were located in saphenous vein grafts. Twenty-two procedures were completed by coronary stenting (17 elective). cTn-T and cTn-I were considered abnormal when serum levels were > 0.2 ng/ml and > 0.6 ng/ml, respectively. CK-MB mass was also determined in all patients (abnormal > 5 ng/ml). No patients had clinical or electrocardiographic evidence of myocardial infarction after the procedure. Overall, 16 patients (28%) developed biochemical evidence of post-procedural MMD (defined as the presence of at least one abnormal sample of any among the three markers tested). Four (7%) had abnormal CK-MB mass (at least one sample), 9 (16%) abnormal cTn-T, and 15 (26%) abnormal cTn-I. When CK-MB mass was elevated, both cardiac troponins were also elevated. In patients positive for MMD and abnormal CK-MB mass, peak cTn-I was significantly higher than in patients with normal CK-MB (3.02 +/- 1.07 vs 1.02 +/- 0.11 ng/ml; p = 0.009). The difference was not evident when comparing the same groups of patients for cTn-T (0.26 +/- 0.04 vs 0.18 +/- 0.10 ng/ml; p = 0.16). Also, peak cTn-I but not peak cTn-T had a positive correlation with peak CK-MB mass (r = 0.89; p < 0.0001 and r = 0.23; p = 0.40). The elevation of either marker of MMD was not related to clinical, angiographic or procedural variables. A possible interpretation for MMD was found in 2/3 of cases: bail-out (2); late occlusion (1); minor side branch occlusion (3); distal embolization from saphenous vein grafts (2) or total occlusions (2). In our series, MMD after PTCA occurs in 28% of cases and is unrelated to clinical, angiographic and procedural variables. Both cTn-T and cTn-I increase the sensitivity of CK-MB mass in the detection of MMD after PTCA, cTn-I being the most sensitive marker. In about 1/3 of cases, the presence of MMD remains unexplained. The prognostic implications of MMD are as yet undefined.

Troponin T, troponin I and creatine kinase-MB mass after elective coronary stenting.

OBJECTIVE: To assess whether and to what extent elective coronary stenting is associated with biochemical evidence of minor myocardial damage (MMD), as defined by the detection of abnormal post-procedural serum levels of one more among the following markers of ischaemic injury: creatine kinase (CK)-MB mass, troponin T (Tn-T) and troponin I (Tn-I). METHODS: Nineteen elective procedure of coronary stenting were compared with a matched group of 25 conventional percutaneous transluminal coronary angioplasty (PTCA) procedures performed in our laboratory from March to June 1995. Cases with evolving or recent (< 2 weeks) myocardial infarction, chronic total occlusions and dilation of saphenous vein grafts were excluded. By definition, all of the patients had undergone uneventful deployment of a single palmaz-Schatz stent, with no chest pain and no persistent ECG changes after the procedure. Serum levels of CK-MB mass, Tn-T and Tn-I were determined at baseline and 6, 12 and 24 h after the procedure. The frequency of abnormal results was determined for each marker. Baseline and peak post-procedural levels in the two groups were compared and related to procedural variables. RESULTS: Baseline values were normal in all cases. The quantitative analysis showed that post-procedural levels of each marker (including total CK) were significantly higher with respect to baseline in both groups. In the stent group, two patients had positive CK-MB mass, four positive Tn-T and seven positive Tn-I. Absolute changes in Tn-T and Tn-I were closely related to changes in CK-MB mass (r = 0.76, P < 0.0001; r = 0.90, P < 0.0001), respectively). Three of these patients developed clinically silent side-branch occlusion. All of them were positive for troponins and two were positive for CK-MB. No correlation was found between procedural variables and the results of biochemical assays. In the PTCA group, three patients were positive for Tn-I, whereas the CK-MB mass and Tn-T remained constantly normal. No side-branch occlusion was observed. The peak CK-MB mass and Tn-I were significantly higher in the stent group than they were in the PTCA group (3.04 +/- 4.1 versus 1.27 +/- 1.3 ng/ml, P = 0.046; 0.78 +/- 1.17 versus 0.28 +/- 0.3 ng/ml, P = 0.046, respectively). This difference was no longer apparent when patients with side-branch occlusion were excluded. CONCLUSIONS: In our series, Tn-I measurement shows the highest ability to detect MMD, being positive in 37% of stent and 14% of PTCA cases. Elective coronary stenting associated with greater release of CK-MB mass and Tn-I than is conventional PTCA. This finding is mainly determined by cases of side branch occlusion, which account for most, but not all, periprocedural MMD in the stent group.

Radiofrequency catheter ablation of the slow reentrant pathway of sustained ventricular tachycardia.

The article reports the cases of two patients with severe coronary artery disease and associated recurrent sustained ventricular tachycardia successfully treated with radiofrequency catheter ablation. In the first patient, two different types of ventricular tachycardia (one incessant) were eliminated. In all procedures, an area of slow conduction critical for tachycardia maintenance was localized by endocardial mapping techniques. Radiofrequency energy delivered to this area could permanently modify the anatomical substrate of the arrhythmia. After single follow-ups of 19, 14, and 13 months regarding the arrhythmic entities, the patients are well and free from spontaneous recurrences.

Plasma 3 alpha-androstanediol glucuronide in precocious adrenarche.

The aim was to study 3 alpha-androstanediol glucuronide (3AG) plasma levels and its relationship with 5-ene and 4-ene steroids in children with the benign form of precocious pubarche (precocious adrenarche). Sixty-five children with precocious adrenarche (PA), aged 3.6-8.2 yr (55 girls and 10 males) and 15 normal age-matched children were studied. We evaluated plasma androstenedione (A), dehydroepiandrosterone (DHA), its sulfate (DHA-S), testosterone (T), dihydrotestosterone (DHT), its glucuronide (DHTG), 3 alpha-androstanediol (3Ad) and its glucuronide (3AG) in all subjects. All androgens are expressed as mean +/- SD. We found significantly higher plasma levels not only in glandular androgens but also in peripheral androgens (A, 2.4 +/- 1.5 nM vs 0.79 +/- 0.46 nM, p < 0.001; DHA, 9.8 +/- 4.9 vs 2.7 +/- 0.76 ng/dl, p < 0.001; DHA-S, 3.4 +/- 2 microM vs 2.4 +/- 0.65 microM, p < 0.05; T, 0.74 +/- 0.5 nM vs 0.4 +/- 0.1 nM, p < 0.001; DHT, 0.36 +/- 0.13 nM vs 0.12 +/- 0.05 nM, p < 0.001; 3Ad, 0.13 +/- 0.1 nM vs 0.054 +/- 0.03 nM, p < 0.001; DHTG, 0.5 +/- 0.3 nM vs 0.26 +/- 0.09 nM p < 0.01). As far as the plasma 3AG levels are concerned we found significantly higher values in PA with respect to controls (1.17 +/- 0.7 nM vs 0.61 +/- 0.04 nM, p < 0.01), suggesting that 3AG may be considered a marker of skin androgen utilization.(ABSTRACT TRUNCATED AT 250 WORDS)

Lack of correlation between sex hormone binding globulin, adrenal and peripheral androgens in precocious adrenarche.

Sex hormone binding globulin (SHBG) is a specific steroid-binding plasma glycoprotein regulated by several different factors. Sex steroids are currently considered to be the main physiological regulators of this protein. Testosterone (T) in adults seems to be the main hormone active in lowering SHBG. The role of dihydrotestosterone (DHT) in such regulation, particularly in the prepubertal age, is not well understood, and no data exist about the role of 3 alpha-androstanediol (3A alpha) and its glucuronide. In adulthood, in addition to T, 5-ene steroids seems to play a role in the regulation of SHBG plasma concentration. To assess the effect of adrenal and peripheral androgens in modulating SHBG levels in the prepubertal age, we studied subjects with precocious pubarche secondary to precocious adrenarche (PA). PA represents, in fact, a good model of study as it is characterized by an increased production and action of adrenal androgen in females under 8 yr of age and in males under 9. Sixty-five subjects (55 females and 10 males; chronologic age: 3.6 - 8.2 yr (6.9 +/- 1.3, SD); bone age: 3.6 - 11 yr (7.6 +/- 1.9); BMI 17.9 +/- 3 kg/m2) were studied. Fifteen age-matched normal children (BMI 15.2 +/- 0.8 kg/m2) were studied as controls. Androstenedione (A), dehydroepiandrosterone (DHA) and its sulphate (DHA-S), T, DHT, 3Ad and its glucuronide (3AG) and SHBG were evaluated in all subjects. In PA cases serum SHBG levels (50 +/- 27 nM) were significantly lower (p less than 0.05) with respect to normal prepubertal patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Atresia of the left main coronary artery: clinical recognition and surgical treatment.

Atresia of the left main coronary artery is an extremely rare anomaly with very few cases presented in the literature. Even more uncommon are reports of successful surgical repair. This article concerns two cases of atresia of the left main coronary artery treated surgically with a favourable outcome. The two patients (a 16 year-old boy and a 43 year-old woman) had a different clinical presentation but identical angiographic and morphologic features. The authors examine the embryogenetic defect underlying this anomaly. The differential diagnosis involves two congenital malformations (single coronary artery and anomalous origin of the left coronary artery from the pulmonary trunk) and acquired atherosclerotic disease of the left main coronary artery; the distinguishing features of these conditions are reviewed. Surgical management by means of internal mammary artery revascularization is discussed in light of recent reports about adequacy of blood flow in internal mammary artery bypass grafts.

[The clinical and prognostic significance of the infarct size in patients discharged after a myocardial infarct]. / Significato clinico e prognostico dell'infarct size nei pazienti dimessi dopo infarto miocardico.

The authors report their experience in the determination of the infarct size (IS) by means of enzymatic analysis in a series of 281 consecutive patients (230 males, 51 females) admitted to the CCU because of myocardial infarction (MI), who did not benefit from thrombolytic therapy in the acute phase. To obtain the enzymatic IS, the serum activity of creatine kinase (CK) is determined every 4 hours for 48 hours and after 72 hours; Sobel's formula is used and results are expressed as CK-g-Eq of tissue. The enzymatic IS was compared to the degree of left ventricular dysfunction (assessed by echocardiography); to the electrocardiographic extension of necrosis; to the severity of ventricular arrhythmias (expressed as Lown's class) on 24-hour Holter monitoring; to cardiac mortality at 2 years. Mean estimated enzymatic IS of the population under study was 129 +/- 101 g-Eq. Patients with extensive MI (216 +/- 144 g-Eq) had significantly (p less than 0.05) higher IS compared to patients with inferior (131 +/- 93 g-Eq), anterior (105 +/- 65 g-Eq) and non-Q wave MI (73 +/- 54 g-Eq); also, a statistically significant difference (p less than 0.05) was found between inferior and non-Q wave MI. Patients with severely compromised left ventricular function (defined as an echocardiographic ejection fraction less than 30%), had significantly higher values of IS compared to patients with preserved left ventricular function (171 +/- 130 vs 120 +/- 93 g-Eq; p less than 0.05). A poor correlation was found between enzymatic IS and ventricular arrhythmias documented at pre-discharge 24-hour Holter monitoring.(ABSTRACT TRUNCATED AT 250 WORDS)

Echocardiographic and pulsed Doppler features in glycogen storage disease type II of the heart (Pompe's disease).

Two cases of cardiac glycogen storage disease type II are described: the first one, male aged 3 months, presented with generalized muscular hypotonia and decreased deep tendon reflexes; a 2/6 systolic murmur was audible at the left sternal border; chest X-ray and ECG were consistent with left ventricular hypertrophy; an echocardiogram disclosed an impressive and diffuse cardiac hypertrophy; the pump function appeared preserved and the estimated ejection fraction was about 70%. Pulsed wave Doppler demonstrated a normal envelope of mitral flow with E/A ratio = 1.27 in averaged 20 beats. The patient died suddenly at 6 months of age. The second patient was a female 4 months old with generalized muscular hypotonia. ECG and chest X-ray were consistent with left ventricular hypertrophy; 2D echocardiogram showed diffuse hypertrophy with estimated ejection fraction of 68% and an almost normal aspect of the mitral flow curve, with E/A ratio of 1.18. This child died at 13 months of age of cardiopulmonary insufficiency. In both cases the diagnosis was made by muscular biopsy and biochemical tests (alpha 1-4 glucosidase deficiency). We stress the fact that, despite the severe and diffuse hypertrophy, the pump function and the ventricular filling did not seem compromised.

Enzyme polymorphism and clinical variability of diseases: study of acid phosphatase locus 1 (ACP1) in obese subjects.

The ACP1*A allele of erythrocyte acid phosphatase (ACP1) has a lower enzymatic activity when compared to other ACP1 alleles and is associated with maximal rate of body growth during intrauterine life. In three different samples of obese subjects (total number = 218). ACP1*A was associated with extreme body mass deviations. No difference in ACP1 allele distribution was observed between obese and nonobese subjects. These data suggest that a genetically determined variability of ACP1 influences the degree of obesity, but only when obesity itself has been triggered by some other factors.

[Transcatheter fulguration of the atrioventricular junction in supraventricular hyperkinetic arrhythmia. Immediate and long-term results]. / Folgorazione transcatetere della giunzione atrio-ventricolare nelle aritmie ipercinetiche sopraventricolari. Risultati immediati e a distanza.

Transcatheter direct-current ablation of the atrio-ventricular junction is a recently developed technique in the treatment of medically refractory supraventricular tachycardia. Twenty patients underwent this procedure between July 1987 and May 1989 and were followed-up for a mean period of 8.3 +/- 6 months (range 1-23). Indication for ablation included atrial flutter in 4 patients, atrial fibrillation in 8, atrial tachycardia in 1, atrio-ventricular nodal re-entrant tachycardia in 4, atrioventricular re-entrant tachycardia (concealed pathway) in 2, permanent junctional reciprocating tachycardia in 1. These arrhythmias were resistant to a mean of 3.3 +/- 1.7 antiarrhythmic drugs. A mean of 1.4 +/- 0.59 (range 1-3) electrical shocks, with a mean energy of 285 +/- 135J (range 200-700), were delivered during 1-2 sessions. In all patients a persistent complete atrio-ventricular block was achieved. Immediate complications included transient hypotension in 2 pts, acute pulmonary edema in 1, premature ventricular complexes in 4, non sustained ventricular tachycardia in 4, sustained ventricular tachycardia in 1. Late complications included thrombophlebitis of the right femoral vein in 2 pts; one of them died suddenly as a result of massive pulmonary embolism 10 days after the procedure. Follow-up evaluation reveals chronic complete atrio-ventricular block in all patients. Symptoms related to pre-existing arrhythmia are absent in all pts and none of them is currently taking antiarrhythmic drugs. Two patients with DDD pacing had pacemaker mediated re-entrant tachycardia and 1 patient with VVIR pacing developed a pacemaker syndrome. This experience confirms that transcatheter fulguration of atrio-ventricular junction is an effective technique. However, possible severe complications related to the procedure suggest this approach be restricted to patients with very symptomatic and drug-refractory supraventricular tachyarrhythmias.

A possible genetic component of obesity in childhood. Observations on acid phosphatase polymorphism.

Phenotypes of acid phosphatase with low enzymatic activity (ACP1 A and BA) are correlated with the highest degree of body mass increase observed in a sample of obese children. Since acid phosphatase probably functions as a flavin-mononucleotide phosphatase, differential modulation of flavo-enzyme activity and energy metabolism due to acid phosphatase genetic variability may explain the observed association.

Effect of hCG or hCG+ treatments in young thalassemic patients with hypogonadotropic hypogonadism.

Hypogonadotropic hypogonadism (HH) is common (40%) in beta-thalassemic patients. Taking into consideration that in HH non-thalassemic patients we obtained good results in pubertal development using hCG treatment (1500 IU every 6 days), 10 HH thalassemic subjects (14 5/12 -17 yr, all with bone age greater than 13 6/12) were treated with the same regimen. In 5 of these patients purified FSH (75 IU every 3 days) was added to hCG in order to evaluate the FSH effect on testosterone (T) response (Group 1 was given hCG alone, Group 2 hCG + FSH: Profasi HP and Metrodin Serono). To evaluate the kinetics of testosterone response, plasma level of T was determined basally and 1, 2, 4 and 6 days after hCG injection. This dynamic study and a clinical examination were carried out at the beginning of treatment and at the 4th and 12th month after. Results obtained in the first group confirmed our previous data from non-thalassemic HH patients: in fact, after 12 months of therapy a stage G2-G3 was reached. In the second group, however, testis size and testosterone secretion were significantly higher than in the first group.(ABSTRACT TRUNCATED AT 250 WORDS)

Interaction at clinical level between erythrocyte acid phosphatase and adenosine deaminase genetic polymorphisms.

The effects of ACP1 phenotype on birth weight, neonatal jaundice, and obesity in children are dependent on ADA genotype. These phenomena may represent a clinical counterpart of the in vitro biochemical interactions between the two systems recently observed by our group.

Subaortic stenosis by solitary rhabdomyoma. Successful excision in an infant following 2D echocardiogram and Doppler diagnosis.

A seven-month-old girl had subaortic stenosis caused by a single intracavitary rhabdomyoma unassociated with tuberous sclerosis. Diagnosis was formulated on the basis of two-dimensional echocardiography and Doppler technique findings alone, and surgery was successful.

[Double mitral valve orifice associated with complete atrioventricular canal. Description of 2 cases]. / Doppio orificio mitralico associato a canale atrioventricolare completo. Descrizione di due casi.

The Authors describe two cases of double mitral valve orifice associated with complete atrioventricular canal. The first patient, 10 month-old male, affected by type A complete atrioventricular canal, underwent surgical repair which was performed in association with division of the tissue bridge between the two orifices. The patient died the day after because of severe mitral insufficiency and pulmonary oedema. The second patient, 3.5 year-old female, affected by type A complete atrioventricular canal with pulmonary banding, underwent a surgical procedure without division of the tissue bridge. In the postoperative period a suture dehiscence occurred which caused severe mitral regurgitation, and another intervention had to be performed; subsequently the patient did well and was discharged in good condition. The Authors discuss the possible role of two dimensional and Doppler echocardiography in the diagnosis of this uncommon condition; they also discuss the related surgical problems and stress the necessity to repair with a proper compromise between residual mitral insufficiency and a mitral stenosis.