Treadmill exercise in Neopolitan children and adolescents.

Two hundred and eighty healthy children from Naples, Italy (140 boys and 140 girls) aged 4-17 years were studied using Bruce walking treadmill protocol to voluntary exhaustion. Endurance time and double product increased with age. Systolic blood pressure increased linearly during the test. Multivariate analysis showed that body weight and age were the best predictors of endurance time. Endurance time averaged 15.2 +/- 2.8 min in boys and 13.7 +/- 2.3 min in girls (p = 0.00001). Mean +/- SD double product at peak exercise was 264.3 +/- 63 (boys) and 242 +/- 44 (girls) (p = 0.01). Sinus arrhythmia was present in 78% of the children and disappeared at a mean heart rate of 112 +/- 16 beats/min during exercise. The voltage of the R wave on V4 lead decreased in all but four children during the test (delta R = -0.25 +/- 0.24 mV). The P and T waves increased in almost all children. No ST depression or upward sloping was detected. The voltage of the PR isoelectric line remained constant. The J point was displaced downwards in 78% of children, unchanged in 11% and displaced upwards in the remaining 11% of the children. The present study gives reference parameters for a walking treadmill test in Southern European children.

Long-term efficacy of nitroglycerin patch in stable angina pectoris.

Subchronic and chronic efficacy of a 10 mg of nitroglycerin (NTG) patch was studied in 30 patients with stable angina pectoris. The trial consisted of 2 periods of study: 1 period of 2 months with a double-blind, crossover, placebo-controlled design and a second period of open treatment with verum patch. Two 7-day washout periods were performed at entry and at the end of the study. Efficacy was evaluated by clinical assessment of anginal attacks and NTG consumption and by means of multistage treadmill exercise testing. Exercise tests were performed at time 0 (24 hours from application of last patch), at 4 and 12 hours after dosing at the end of first 7-day washout, at the end of the first month of treatment, at the end of the second month of treatment after crossover, at the end of 3 months of treatment with active patch and at the end of the second 7-day washout period. Statistics were obtained by multivariate analysis of difference. In 27 patients whose records were available for final analysis the daily attacks of angina and NTG consumption decreased significantly during both the subchronic and chronic phases of the trial compared with placebo (p less than 0.001). Subchronic study showed significant improvement of maximal exercise duration, time to onset of angina, time to ST-segment depression of 1.0 mm, time to regression of angina and time to regression of ST depression, compared with placebo.(ABSTRACT TRUNCATED AT 250 WORDS)

Intravenous amiodarone in acute anterior myocardial infarction: a controlled study.

A randomized, single-blind controlled study intended to assess the potential benefits of intravenous amiodarone in anterior myocardial infarction is presented. Three hundred nineteen patients entered the study, 159 received amiodarone infusion, and 160 received glucose-insulin-potassium (GIK) infusion. Basal characteristics were similar in the two experimental groups, who were randomized on a consecutive basis. Exclusion criteria were shock or pulmonary edema, hypotension, inferoposterior infarction, bradycardia, antrioventricular block, severe diabetes, and other major diseases. Patients aged 27 to 70 years, with a Q-wave anterior infarction, initiated 12-40 hours earlier at the time of admission, entered the trial. Other entry criteria were heart rate higher than 80 beats/min and systolic blood pressure higher than 100 mmHg. Amiodarone was administered in saline infusion 10-20 mg/kg, within 4 to 10 hours, through a central vein. GIK infusion consisted of 150-300 g of glucose, 25-50 IU of insulin, and 80-120 mEq of KCl in 1000 cc of water at a rate of 1.5-2.0 ml/g/hour. Both groups received digitalis, nitrates, sedatives, and diuretics as needed. Although individually the major endpoints of death, reinfarction, and sustained supraventricular and ventricular arrhythmias did not differ significantly, each was less in the amiodarone group than in the control, and the sum of all adverse events was significantly lower for the amiodarone patients (p less than 001). Heart failure and conduction disturbances were not different in the two groups. This study shows that amiodarone, with its vasodilating and antiarrhythmic properties, may be beneficial in acute anterior infarction, but further studies on larger populations will be necessary in order to show a reduction of mortality rate.

Efficacy of a new transdermal nitroglycerin patch (Deponit 10) for stable angina pectoris.

In this double-blind randomized placebo-controlled crossover study, the antianginal and anti-ischemic effect of a new transdermal system, releasing 10 mg of nitroglycerin (NTG) over 24 hours, was assessed in 19 outpatients with stable exercise-induced angina pectoris. The trial consisted of a 3-day washout: a 1-week period with verum or placebo patch followed by a second 1-week period with the other patch. During the study only sublingual NTG was allowed, and its consumption and the number of attacks recorded. Treadmill exercise tests were performed at the end of washout before patch application (baseline test) and 3 and 24 hours, respectively, after each period of 7 days of application of 1 patch daily. Systolic blood pressure and heart rate did not vary significantly at rest in the 17 patients who completed the trial. Angina was reduced 31.3% and NTG consumption 34.3% (p less than 0.01) during the week with Deponit 10 as compared with placebo. Exercise duration increased 29 and 16.1% (p less than 0.001 and p less than 0.1, respectively) at 3 and 24 hours with a verum patch as compared with placebo. ST-segment depression at comparable loads decreased 69 and 40.5% (p less than 0.01) at 3 and 24 hours, respectively, after application of Deponit. Onset of angina was delayed and maximal heart rate-blood pressure product significantly increased at 3 and 24 hours of treatment. It is concluded that Deponit 10 patch is effective in reducing anginal attacks and in increasing exercise capacity up to 24 hours after application.

10-year follow-up of patients with intraventricular conduction defects associated with myocardial infarction: the meaning of QRS duration.

The 10-year survival rate of 66 patients discharged after an acute myocardial infarction associated with intraventricular conduction delay is reported. The whole population under study consisted of 321 patients followed for 10 years or until death. In 46 patients (69.7%) the conduction delay was a definite complication of infarction, in 15 (22.7%) it preceded the acute event and in 5 (7.5%) the time of onset was undetermined. Mortality in the presence of a conduction delay was 74.2% in 10 years vs 39.2% in its absence (p less than .001). Death was sudden in 41.6% of fatalities when a conduction defect was present and 28% in its absence (p less than .01). The 10-year survival was 55% in patients with conduction defects and QRS less than .12 sec duration, 23.8% if QRS was between .12 and .14 sec, and 4% when QRS duration was greater than .14 sec. 72% of patients of this latter group was in NYHA class 3 or 4, whereas 70% of patients with QRS less than .12 sec and 47% of patients with QRS .12 to .14 sec were in class 1 or 2. These data show that long-term prognosis of conduction delay associated to myocardial infarction is poor and stratification of risk of death is possible among these patients on the basis of QRS duration.

[Long-term (10 years) predictive value of the exercise test after myocardial infarct and significance of the longitudinal repetition of the test during follow-up]. / Valore predittivo a lungo termine (10 anni) della prova da sforzo nel post-infarto e significato della ripetizione del test longitudinalmente nel corso del follow-up.

Our follow-up after myocardial infarction consists of 321 patients followed for 10 years or until death. 147 patients, free of clinical features associated with high risk of subsequent events, underwent a late exercise test at cycloergometer 6 to 17 months after infarction. Ten year mortality was 48.3% and 10.3% in patients with a positive or a negative test respectively (p less than 0.0001). Incidence of nonfatal reinfarction was 4.6% and 33.3% respectively (p less than 0.001). 108 patients underwent a second test later in the follow-up (2.8 +/- .9 years): in 27 patients who were positive at first test the second test was also positive and mortality was 33.3%. Sixteen out of 81 patients with a former negative test resulted positive at a repeat test and mortality was 37.5% vs a 3% mortality rate among 65 patients who were negative at both tests. Thus long-term prognostic significance of exercise stress testing after acute myocardial infarction is confirmed and extended, despite limitation of a late test. Moreover, the second test along the follow-up allows further stratification. In conclusion, patients with a negative test and without clinical features predictive of poor prognosis constitute a very low risk group who need not undergo invasive testing, whereas patients with a positive result or who become positive at following test deserve further evaluation and may become bypass candidates in the ensuing years.

[10-year survival after myocardial infarction. Longitudinal study of a hospital population]. / Sopravvivenza a 10 anni dopo l'infarto del miocardio. Studio longitudinale su una popolazione ospedaliera.

In this study, 321 patients discharged from hospital after an acute myocardial infarction were followed for 10 years or until death. Death rate was 46.4% and 30.8% of all fatalities was sudden. In over 80% of the cases death was from cardiac causes and frequently occurred out of hospital. Univariate analysis showed that age, female sex, previous infarction, diabetes, heart failure during hospitalization, heart murmur, NYHA class III or IV, post-infarction angina, intraventricular conduction defects, cardiomegaly, ST displacement, were all associated with an increased death rate. A positive exercise test 6-17 months after infarction, was associated with a 4-fold mortality increase. Bypass played a minor role in this series since only 6.8% of the patients underwent this operation. A nonfatal infarction recurred in 71 patients (22.1%) with an annual rate of 2.2%. Annual death rate after the first 2 years of follow-up was 3.9%, as in most recent reports on survival after myocardial infarction.

Exercise-induced arrhythmias: angiographic correlation and follow-up.

The meaning of exercise-induced arrhythmias was studied in 409 patients who underwent a maximal treadmill test, coronary and ventricular angiography and were followed for 31 +/- 10.6 months. The original population consisted of 1720 patients, of whom 520 were assigned to a group of known or strongly suspected coronary artery disease (Group I) and 1200 were assigned to a group with low likelihood of coronary artery disease (Group II). This division was based on age, history and symptoms. Two hundred and forty-seven (47.5%) patients of group I and 218 (18%) of group II developed ventricular premature beats during the exercise test or the recovery period. The test was positive in 378 (72.6%) patients of group I and in 190 (15.8%) of group II. A complete invasive angiographic study was performed in 233 (44%) patients of group I and 176 (14.6%) of group 2. Exercise-induced ventricular premature beats (VPBs) predicted neither coronary anatomy nor subsequent coronary or surgical events, but a weak relationship was observed with a lower ejection fraction among group I patients. On the other hand, a positive test was predictive of coronary anatomy in both groups and of coronary events in group I. We conclude that, despite a higher prevalence of exercise-induced ventricular premature beats among patients with definite coronary artery disease, an exercise test presenting ventricular premature beats as the only abnormality should not be classified as positive. Patients with such results require further investigation.

[Prevalence of hyperkinetic arrhythmias in a healthy infantile and adolescent population: correlations between standard ECG, stress test and dynamic ECG]. / Prevalenza di aritmie ipercinetiche in una popolazione infantile e adolescente sana: correlazioni fra ECG standard, prova da sforzo ed ECG dinamico.

We evaluated 250 males and 250 females 4 to 17.99 years old, randomly recruited among school-children. Cardiac and other diseases were excluded. All the subjects were studied with a standard ECG iun the standing and supine position for a minute. Three hundred children underwent a treadmill exercise test according to Bruce's protocol and 50 of them had a 24-hour ambulatory ECG monitoring. Sinus arrhythmia was present in 94% of the children in supine position and in 87% of them while they were standing. Only one child had atrial and ventricular premature beats. In a boy a slow ventricular tachycardia was recorded. One child had a WPW and a girl a short PR interval; both were asymptomatic. The exercise test did not induce any arrhythmias and the slow ventricular tachycardia, in the previously mentioned boy was suppressed during exercise and reappeared during the recovery period. The premature beats were greatly reduced in the child who had them during the standard ECG recording. The 24-hour ambulatory ECG monitoring showed only minor degrees of premature atrial and ventricular beats in 24% of the children studied by this method. The maximum number of premature beats was 39 in 24 hours and never exceeded the first grade of Lown's classification. We conclude that a good correlation exists among the three employed techniques in the study of the prevalence of tachyarrhythmias in healthy children. This is the first study that compares these three techniques in a pediatric population.