A new integrated instrumental approach to autonomic nervous system assessment.

BACKGROUND AND OBJECTIVES: The autonomic nervous system (ANS) regulates involuntary body functions and is commonly evaluated by measuring reflex responses of systolic and diastolic blood pressure (BP) and heart rate (HR) to physiological and pharmacological stimuli. However, BP and HR values may not sufficient be to explain specific ANS events and other parameters like the electrocardiogram (ECG), BP waves, the respiratory rate and the electroencephalogram (EEG) are mandatory. Although ANS behaviour and its response to stimuli are well-known, their clinical evaluation is often based on individual medical training and experience. As a result, ANS laboratories have been customized, making it impossible to standardize procedures and share results with colleagues. The aim of our study was to build a powerful versatile instrument easy-to-use in clinical practice to standardize procedures and allow a cross-analysis of all the parameters of interest for ANS evaluation. METHODS: The new ANScovery System developed by neurologists and technicians is a two-step device: (1) integrating physiological information from different already existing commercial modules, making it possible to cross-analyse, store and share data; (2) standardizing procedures by an innovative tutor monitor able to guide the patient throughout ANS testing. RESULTS AND CONCLUSIONS: The daily use of the new ANScovery System in clinical practice has proved it is a versatile easy to use instrument. Standardization of the manoeuvres and step-by-step guidance throughout the procedure avoid repetitions and allow intra and inter-patient data comparison.

REHAL®, a telemedicine platform for home cardiac rehabilitation.

AIM: The new REHAL® platform manages home-based cardiac rehabilitation programs without most of the drawbacks of an earlier E-Remedy EC proposal. The proposal is based on the awareness that safe home rehabilitation is only possible in the post-hospital phase when the patient no longer needs direct control by medical staff and has become accustomed to the technological set-up. METHODS: The platform is composed of a web-based database and client software (Ergomonitor), which allows health staff to manage the sessions without a real-time connection and legal liability. Ergomonitor permits the complete management of a bike (training session settings, web transmission and data recording) by a serial connection to a PC. Patients own their data and may approve the access of health personnel to evaluate the results and introduce longitudinal ambulatory information together with updated physical activity protocols. The health service does not bear the cost of the technological set-up. Ergomonitor acquires and records heart rate, loads, pedalling speed and other parameters of interest (i.e., arterial pressure) and forwards data to a remote database. Health personnel can modify time by time the scheduled exercise settings, analyse the results of each session and compare session by session. RESULTS: The platform is actually used in hospital, gymnasium and home context. More than 1000 subjects have been enrolled in the protocol, with a very good appreciation. CONCLUSION: The first experience of REHAL® (six months, more than 1000 enrolled patients) highlights the positive aspects of the solution: the patients are very satisfied with the continuity of the rehabilitation programme and the clinicians are very satisfied they can follow their patient population longitudinally and with a personalized protocol.

Changes in exercise capacity induced by heart transplantation: prognostic and therapeutic implications.

Survival and exercise performance are key targets of heart transplantation (HT). We designed this study to help in identifying (1) patients with chronic heart failure (CHF) at risk of poor exercise capacity after HT and (2) HT recipients presenting risk factors modifiable with exercise showing a potential impact on outcome. We enrolled 49 HT recipients (age 52 ± 12 years, 84% males) who underwent a cardiopulmonary exercise test before (9 ± 6 months) and after (20 ± 14 months) HT. In the CHF phase, lower peak oxygen consumption (VO(2) ) (odds ratio 0.69, P=0.017) independently predicted peak VO(2) improvement after HT. In the post-HT phase, body mass index (BMI) [adjusted hazard ratio (HR) 1.16, P=0.034] and VE (ventilation)/VCO(2) (carbon dioxide production) slope (adjusted HR 1.07, P=0.031) independently predicted mortality. In conclusion, CHF patients with only a moderate impairment of peak VO(2) are at a risk of failing to achieve a significant improvement of exercise performance after HT. In the post-HT phase, a BMI≥28 and/or a VE/VCO(2) slope ≥47 represent risk factors for death, which are potentially modifiable with exercise. Prospective randomized studies are needed to analyze the effects of training on functional capacity and outcome in the different subsets of HT recipients.

Evaluation of the dose to the patient and medical staff in interventional cardiology employing computational models.

Interventional radiology, among guided X-rays procedures, is a methodology characterised by high level of doses, both for the patient and for the medical staff. The aim of the present study is to estimate the dose associated with coronary angiography procedures by means of numerical models (simplified and anthropomorphic) and MCNPX Monte Carlo code. Numerical estimates were supported by measurement performed with a dose area product meter that is commonly employed in such kind of studies. In the present work the main considerations and the preliminary results are presented.

Atrial fibrillation recurrence after internal cardioversion: prognostic importance of electrophysiological parameters.

OBJECTIVE: To evaluate the clinical and electrophysiological determinants of arrhythmia recurrence in patients undergoing internal atrial cardioversion for chronic atrial fibrillation (AF). SETTING: Tertiary cardiac referral centre. METHODS: 101 consecutive patients with failed external cardioversion or AF > or = 1 year underwent internal atrial cardioversion; once stable sinus rhythm (SR) was obtained, electrophysiological study was performed in 73 patients (72%) who gave informed consent. Patients were then followed on antiarrhythmic treatment. RESULTS: 101 consecutive patients underwent internal atrial cardioversion in the period 1996-1999 with 100% conversion to SR; prophylactic antiarrhythmic treatment was flecainide (52%), amiodarone (37%), and sotalol (11%). Average follow up at first AF recurrence was 18.4 (14.4) months (range 0.1-49.8 months); persistence of SR was observed in 72/101 (72%) patients. By logistic regression, AF duration (odds ratio (OR) 1.07, 95% confidence interval (CI) 1.01 to 1.13) and a lower sinus rate at discharge on antiarrhythmic drugs (OR 0.92, 95% CI 0.85 to 0.99) were independent predictors of AF recurrence, whereas age, New York Heart Association functional class, left atrial dimensions, and left ventricular ejection fraction were not predictive of arrhythmia recurrence. When electrophysiological parameters were added to the statistical model in 73 patients, a shorter atrial effective refractoriness (OR 1.04, 95% CI 1 to 1.08) and an abnormal relation of atrial effective refractoriness to cycle length (OR 31, 95% CI 3.7 to 266) were also independent predictors of AF recurrence at follow up, beyond AF duration and heart rate at discharge. CONCLUSIONS: Patients with failed external cardioversion or long lasting AF may benefit from internal atrial cardioversion and antiarrhythmic treatment to keep SR at long term; electrophysiological study may identify patients at the highest risk of arrhythmia recurrence. Although preservation of SR seems unlikely for AF duration > 3 years, a consistent minority of this subgroup (38%) may benefit from this approach.

Internal low energy atrial cardioversion: efficacy and safety in older patients with chronic persistent atrial fibrillation.

BACKGROUND: Low-energy internal atrial cardioversion is a relatively new technique based on delivery of intracardiac shocks through transvenous catheters placed into the atria or the vessels. OBJECTIVE: The aim of this study was to assess in older and younger patients with chronic persistent atrial fibrillation (AF) the efficacy and safety of transvenous low-energy internal atrial cardioversion performed without routine administration of sedatives or anesthetics. DESIGN: A prospective longitudinal study. SETTING: A cardiological university hospital. PARTICIPANTS: 82 patients, divided into older (> or = 60 years) (n = 49) and younger (n = 33) subjects. MEASUREMENTS: Atrial defibrillation threshold for internal cardioversion, measured as leading edge voltage (V) and delivered energy (J) of effective shocks, percentage of patients maintaining sinus rhythm at short-term (within 3 days) and at long-term follow-up. METHODS: Patients with chronic persistent AF, treated with oral anticoagulants for at least 3 to 4 weeks, were admitted to hospital. Following a clinical work-up, patients were subjected to low-energy internal atrial cardioversion with shock delivery according to a step-up protocol. RESULTS: Internal cardioversion was effective in restoring sinus rhythm in 90% (44/49) of the older patients and in 94% (31/33) of the younger patients. Shocks were effective at a mean energy between 6 and 8 joules (range 0.9-23) and administration of sedatives or anesthetics was required during the procedure in 22% (11/49) of older and in 48% (16/33) of younger patients (P = .026 at chi-square). No major complications occurred during the procedure. Pharmacological prophylaxis of AF recurrences was instituted immediately following the procedure. During inhospital stay and during the follow-up (mean 12 +/- 9 months for older patients and 15 +/- 10 months for younger patients), AF recurred in 39% (17/44) of older patients and in 16% (5/31) of younger subjects (P = .064 at chi-square). CONCLUSIONS: Internal low energy cardioversion is a very effective procedure for restoring sinus rhythm in patients with AF; it can be performed in older patients, and administration of sedatives or anesthetics can be avoided or minimized in a substantial proportion of subjects. Recurrences of AF in the long term tend to be higher in older subjects and intensive prophylaxis with antiarrhythmic drugs is required.

Management of patients with atrial fibrillation: different therapeutic options and role of electrophysiology-guided approaches.

At present the approach to atrial fibrillation treatment is based on the electrophysiological patterns of atrial fibrillation (on the basis of multiple intra-atrial recordings or sophisticated new mapping techniques) only in a restricted minority of patients, those who are candidate to ablation of the substrate and/or of the triggers. Atrial fibrillation has a broad spectrum of clinical presentations and a heterogeneous electrophysiological pattern. The treatment of this arrhythmia, both with drugs and non pharmacological treatments, has been based, classically, on empirical basis and on a clinically-guided staged-approach. The limitations of pharmacological treatment led in recent years to the development of a wide spectrum of non pharmacological treatments. This implies a change in the approach to atrial fibrillation and the need to identify potentially ideal candidates to complex and expensive treatments. In this view it is currently under investigation the possibility to identify potential responders to a definitive treatment or a combination of treatments (both pharmacological and non-pharmacological) on the basis of the electrophysiological pattern.

Evaluation of myocardial injury following repeated internal atrial shocks by monitoring serum cardiac troponin I levels.

INTRODUCTION: Electrical shocks delivered for atrial cardioversion (CV) may cause myocardial damage. The aim of this study was to assess the extent of myocardial injury caused by repeated intracardiac shocks delivered for low-energy internal atrial CV. METHODS AND RESULTS: Thirty-five patients with chronic persistent atrial fibrillation (AF) of different etiologies underwent CV with delivery of synchronized biphasic shocks (3.0/3.0 ms) between two catheters positioned in the right atrium and the coronary sinus. Shocks were delivered according to a step-up protocol (50 V, 180 V, then steps of 40 to 56 V up to 500 V, if necessary). In 23 patients, AF was reinduced after baseline CV, and CV was repeated. Myocardial injury was monitored by measuring cardiac troponin I (cTnI) serum concentrations in blood samples taken at baseline and at 2, 4, 8, 12, and 24 h after the procedure, by means of an immunoenzymologic assay (normal values, < or =0.6 ng/mL). A mean (+/- SD) of 6.9 +/- 3.4 shocks per patient were delivered (range, 2 to 17). Shocks delivered in each patient had a maximal energy of 7.3 +/- 4.0 J (range, 1.7 to 15.7). In 20 patients (57%), no evidence of myocardial injury (cTnI level, < or = 0.6 ng/mL) was found. In 13 patients (37%), mildly elevated cTnI levels (range, 0.7 to 1.4 ng/mL) in samples taken 4 to 12 h after CV suggested minor myocardial injury. In two patients (6%), higher cTnI levels were found in samples taken 4 to 8 h after CV (peak, 1.7 and 2.4 ng/mL), indicating a necrotic damage. Patients with no cTnI elevation, with mild cTnI elevation, or with cTnI levels >or =1.5 ng/mL did not differ significantly with respect to the total number of shocks delivered, the mean amount of energy delivered, and the cumulative amount of energy delivered. No clinical complications were observed. CONCLUSIONS: Following internal CV with the delivery of repeated shocks, minor elevations of cTnI serum levels could be detected in a significant proportion of patients, and this suggests subtle asymptomatic minor myocardial injury. The elevations of cTnI levels do not appear to be related to the number of shocks or to the amount of energy delivered.

Predictors of atrial defibrillation threshold in internal cardioversion.

This study examined the clinical, echocardiographic, and electrophysiological factors influencing the atrial defibrillation threshold (ADFT) in patients with chronic, persistent AF undergoing transvenous, low energy, atrial cardioversion. Twenty-two patients (age 57 +/- 15 years) with a mean AF duration of 7.8 +/- 7.1 months (range 2-32 months) underwent internal cardioversion with catheters placed in the right atrium and coronary sinus. Biphasic shocks (3/3 ms) were delivered in a step-up protocol. ADFT was defined as the lowest energy shock that converted AF to sinus rhythm. All patients were successfully cardioverted at a mean ADFT of 5.62 +/- 2.82 J (range 2.6-12.9 J). Fifteen variables, including clinical characteristics (age, body mass index, AF duration, etiology), echocardiographic measurements (atrial diameter and volumes, indexes of ventricular performance), hemodynamic measurements, and mean atrial cycle during AF were analyzed as possible predictors of ADFT. In univariate regression analysis, AF duration, mean RR interval, and cardiac index correlated with ADFT. In multivariate regression analysis, AF duration remained as the only significant predictor of ADFT (B coefficient 0.311, P < 0.001; 95% confidence interval [CI] 0.194-0.427). AF duration was the most powerful predictor of ADFT. It should be considered when planning internal CV of AF to limit the number of shocks delivered. Furthermore, long intervals between AF onset and CV should be avoided.

Repolarization changes in a double-blind crossover study of dofetilide versus sotalol in the treatment of ventricular tachycardia.

UNLABELLED: The aim of this study was to determine whether a therapeutic response to Class III antiarrhythmic drugs is related to predictable changes in repolarization on the electrocardiogram (ECG). A group of 57 patients with ischemic heart disease and inducible ventricular tachycardia (VT) at electrophysiological study (EPS) were selected from a population enrolled in a randomized double-blind crossover study of dofetilide (500 micrograms bid) versus sotalol (160 mg bid). ECGs were analyzed blindly, and RR, QT (maximum value/12 leads), QTc (Bazett's formula), QT dispersion (QTmax-QTmin over 12 leads) and QTc dispersion, were calculated at baseline and on the third day of treatment (4 hours after dosing), when patients underwent EPS to test the effects of study drugs on VT inducibility. RESULTS: At EPS 21 patients were responders to dofetilide and 22 to sotalol. On day 3, a significant increase in QT and QTc and decrease in QT and QTc dispersion, compared to baseline, was measured in responders and nonresponders, with both dofetilide and sotalol. No significant difference in QTc or QT dispersion between responders and nonresponders was observed in either treatment group. In conclusion, treatment with dofetilide and sotalol was associated with an increase in QT and QTc, and a decrease in QT and QTc dispersion. In contrast with previous reports, a differential effect on QT or QTc dispersion was not observed in drug responders versus nonresponders.

Transvenous internal cardioversion for atrial fibrillation: a randomized study on defibrillation threshold and tolerability of asymmetrical compared with symmetrical shocks.

UNLABELLED: The aim of the study was to compare, according to a randomized cross-over design, two different biphasic waveforms (6.5/2.5 ms and 3.0/3.0 ms phases duration, respectively) for low energy internal atrial cardioversion with regard to energy requirements for cardioversion and shock induced discomfort. METHODS: Nineteen patients with chronic persistent atrial fibrillation (AF)(mean duration 16+/-20 months) were submitted to internal atrial cardioversion (shock delivery between catheters in right atrium and coronary sinus, respectively) and were randomly allocated to baseline cardioversion with an asymmetrical biphasic shock (6.5/2.5 ms) or with a symmetrical biphasic shock (3.0/3.0 ms), according to a step up protocol. After baseline cardioversion, a sustained AF was reinduced and the patients crossed to the alternative waveform. The procedure was performed without routine administration of sedatives and shock induced discomfort was monitored by a subjective score (1 to 5). Sedatives or anesthetics were administered at patient's request. RESULTS: The procedure was effective in all the patients and was performed without need for sedatives/anesthetics in 17/19 patients (89%). Leading edge voltage of effective shocks resulted lower for asymmetrical shocks compared to symmetrical shocks (290+/-76 vs. 337+/-104 V, P<0.001) with no statistically significant differences in delivered energy (7.74+/-4.25 vs. 8.65+/-5.94 J). Moreover shock induced discomfort resulted lower for asymmetrical shocks compared to symmetrical (pain score=4.18+/-0.73 vs. 4.59+/-0.62, P<0.02). Shock impedence of effective shocks was 59+/-10 ohms for both waveforms. No significant complications occurred during the procedure and no ventricular arrhythmia was observed after atrial cardioversion. Transient bradycardia requiring support ventricular pacing was observed in one patient. CONCLUSIONS: Delivery of biphasic asymmetrical shocks (6.5/2.5 ms) results in lower leading edge voltage of effective shocks and better patients tolerability compared with conventional biphasic symmetrical shocks (3.0/3.0 ms). These findings are of interest both for transvenous internal cardioversion of chronic persistent AF and for implantable atrial defibrillators.

Effects of wave reflection timing on left ventricular mechanics.

UNLABELLED: The aim of this study was to evaluate how the timing of the pressure pulse produced by peripheral reflection affects the left ventricle (stroke volume, ventricular work, coronary driving pressure). Ten isolated perfused rabbit hearts were attached to rubber tubes of different lengths (0.5, 0.8 and 1 m) connected to a hydraulic resistance. The different lengths produced reflections at different times and the reflected pulse returned to the ventricle in early (at 84 ms), middle (at 134 ms) and late systole (at 168 ms) for the three tubes, respectively. The loading parameters (ventricular filling pressure and hydraulic resistance) were not changed during the procedure. Ventricular and aortic pressure and aortic flow were monitored continuously and recorded; cardiac cycle was fixed at 800 ms. An operator-independent procedure was used to calculate instantaneous and total systolic external work, mean diastolic aorto-ventricular pressure difference and ventricular stroke volume. RESULTS: The mean value of stroke volume for the three different length rubber tubes was 320 +/- 71, 348 +/- 77 and 368 +/- 87 microliters, respectively. The mean value of total external work was 20.3 +/- 8.3, 22.5 +/- 8.8 and 24.2 +/- 9.6 mJ, respectively. The mean aortoventricular pressure difference was 40 +/- 12, 46 +/- 13, 50 +/- 14 mmHg, respectively (1 mmHg = 133 Pa). The differences between the parameters measured in the three conditions were statistically significant (p < 0.05). A reduction of reflection timing, reduces, on a pure mechanical basis, cardiac output and external ventricular work and has a negative effect on coronary driving pressure.

Low energy internal atrial cardioversion in atrial fibrillation lasting more than a year.

UNLABELLED: The aim of this study was to evaluate the efficacy of low energy internal atrial cardioversion in restoring sinus rhythm (SR) in patients with chronic atrial fibrillation (AF) persisting > 1 year. Fifteen patients with chronic AF lasting > 1 year (from 13-48 months, mean 24 +/- 13 months) were studied. R wave synchronized 3/3 ms biphasic shocks were delivered between right atrial and coronary sinus (left pulmonary artery in five patients) electrodes. Sedatives or anesthetics were administered only at the patient's request. RESULTS: Stable SR was restored in 14 (93%) of 15 patients after shocks with a mean leading edge voltage of 377 +/- 77 V (range 260-500) and a mean delivered energy of 7.3 +/- 3.4 J (range 2.6-12.9). The procedure was performed without anesthesia in 6 (40%) patients. All successfully cardioverted patients were treated with flecainide, sotalol, or amiodarone. During a follow up of 7.7 +/- 7.9 months (range 1-24) AF recurred in five (36%) patients. Three of five AF recurrences occurred within 3 days after conversion to SR. CONCLUSION: Internal low energy atrial cardioversion is highly effective in restoring SR even in patients with AF lasting > 1 year. The long-term results from the standpoint of freedom from AF recurrences, are satisfactory, although additional antiarrhythmic treatment is required, particularly in the first days after conversion.

Favorable effects of flecainide in transvenous internal cardioversion of atrial fibrillation.

OBJECTIVES: The aim of the study was to evaluate the effects of intravenous (IV) flecainide on defibrillation energy requirements in patients treated with low-energy internal atrial cardioversion. BACKGROUND: Internal cardioversion of atrial fibrillation is becoming a more widely accepted therapy for acute episode termination and for implantable atrial defibrillators. METHODS: Twenty-four patients with atrial fibrillation (19 persistent, 5 paroxysmal) underwent elective transvenous cardioversion according to a step-up protocol. After successful conversion in a drug-free state, atrial fibrillation was induced by atrial pacing; IV flecainide (2 mg/kg) was administered and a second threshold was determined. In patients in whom cardioversion in a drug-free state failed notwithstanding a 400- to 550-V shock, a threshold determination was attempted after flecainide. RESULTS: Chronic persistent atrial fibrillation was converted in 13/19 (68%) patients at baseline and in 16/19 (84%) patients after flecainide. Paroxysmal atrial fibrillation was successfully cardioverted in all the patients. A favorable effect of flecainide was observed either in chronic persistent atrial fibrillation (13 patients) or in paroxysmal atrial fibrillation (5 patients) with significant reductions in energy requirements for effective defibrillation (persistent atrial fibrillation: 4.42+/-1.37 to 3.50+/-1.51 J, p < 0.005; paroxysmal atrial fibrillation: 1.68+/-0.29 to 0.84+/-0.26 J, p < 0.01). In 14 patients not requiring sedation, the favorable effects of flecainide on defibrillation threshold resulted in a significant reduction in the scores of shock-induced discomfort (3.71+/-0.83 vs. 4.29+/-0.61, p < 0.005). No ventricular proarrhythmia was observed for any shock. CONCLUSIONS: Intravenous flecainide reduces atrial defibrillation threshold in patients treated with low-energy internal atrial cardioversion. This reduction in threshold results in lower shock-induced discomfort. Additionally, flecainide may increase the procedure success rate in patients with chronic persistent atrial fibrillation.

Evaluation of atrial refractoriness and atrial fibrillation inducibility immediately after internal cardioversion in patients with chronic persistent atrial fibrillation.

OBJECTIVE: To prospectively evaluate right atrial refractoriness and sustained atrial fibrillation (AF) inducibility at programmed electrical stimulation in two groups of patient: a series of patients with chronic persistent AF, studied immediately after successful low energy internal atrial cardioversion, and a group of control patients without history of supraventricular arrhythmias. PATIENTS: Nineteen patients with chronic persistent AF (mean AF duration 11 +/- 10 months, range 2-61 months) submitted to successful internal low energy atrial cardioversion in fully conscious state and 11 control patients without history of supraventricular arrhythmias. METHODS: An electrophysiological evaluation was performed to measure atrial refractoriness and AF inducibility, by delivering single atrial extrastimuli in high right atrium, at decremental coupling, during spontaneous sinus rhythm and after 8 beats at 600, 500, 400 and 330 ms cycle length. If sustained AF was induced the protocol was terminated. RESULTS: During programmed atrial stimulation sustained AF was induced in 8 out of 19 (42%) of the AF patients but in none of the control group. Atrial effective refractory period was significantly shorter in AF patients compared to controls both at basic cycle length, at 600 ms, 500 ms and 400 ms cycle length, meanwhile no statistically significant differences were found at 330 ms cycle length. An altered relationship between atrial effective refractory period and cycle length was found in AF patients compared to controls: the slope of linear correlation slope was significantly lower in AF group than in controls (0.04 +/- 0.07 vs 0.17 +/- 0.10, p < 0.002). CONCLUSIONS: Marked abnormalities of atrial refractoriness and of its heart rate relationship are observed after internal cardioversion of chronic persistent AF in humans and these abnormalities are associated with an high vulnerability to AF. These observations may explain the high risk of AF recurrences in the early phases following successful cardioversion. In this scenario antiarrhythmic drug therapy seems to be mandatory for reducing arrhythmia relapses.

Efficacy and tolerability in fully conscious patients of transvenous low-energy internal atrial cardioversion for atrial fibrillation.

Transvenous low-energy atrial cardioversion was performed in a series of fully conscious patients (30 patients with chronic atrial fibrillation and 5 patients with paroxysmal atrial fibrillation). The results show that internal atrial defibrillation is effective and tolerable in most patients.

Malignant vasovagal syncope: a randomised trial of metoprolol and clonidine.

OBJECTIVE: To evaluate the efficacy of head up tilt guided treatment with metoprolol and clonidine in preventing the recurrence of syncope in patients with malignant vasovagal syncope. PATIENTS: 20 patients (9 men and 11 women, mean age 33 (SD 17), range 14 to 62 years) with severe symptoms. DESIGN: Randomised double blind crossover trial; efficacy was assessed by head up tilt testing. RESULTS: Metoprolol was more effective than clonidine in abolishing syncope (19/20 v 1/20, P < 0.001) but clonidine showed some beneficial effects on time to syncope and severity of hypotension in 12 patients. During an average follow up of 15 (3) months there was a significant reduction in the recurrence of symptoms compared with the previous year in patients who had tilt up guided treatment (18 metoprolol, 1 clonidine). CONCLUSIONS: Treatment guided by head up tilting is a reliable method of treating patients with malignant vasovagal syndrome. Metoprolol was an effective long term treatment for preventing syncope. High doses were more effective and a careful dose titration period helped to minimise withdrawal symptoms and side effects.

Dynamic planar myocardial perfusion imaging in patients with one-vessel disease with intracoronary injection of technetium 99m teboroxime during papaverine-induced coronary hyperemia.

This study examined the imaging results and kinetics of technetium 99m teboroxime after its intracoronary injection during papaverine-induced coronary hyperemia in patients with one-vessel disease before and after coronary angioplasty. Thirteen patients with > or = 90% diameter stenosis of either the left anterior descending or the left circumflex coronary artery were included. Two patients were excluded because of ventricular tachycardia during papaverine injection in one patient and unsuccessful angioplasty in the second patient. One mCi of technetium 99m teboroxime was injected into the left main coronary artery during coronary hyperemia induced by intracoronary injection of papaverine. Dynamic acquisition in a frame mode (20 sec/frame) was performed for 5 minutes in the left anterior oblique projection with a multicrystal gamma camera before and after successful angioplasty. Ischemic:normal count ratio increased from 0.75 +/- 0.4 before to 1.00 +/- 0.50 after angioplasty (p < 0.1). The T 1/2 of teboroxime was 6.5 +/- 1.5 min in the normal zone and 7.2 +/- 1.9 min in the ischemic zone (p, NS). Perfusion defects were visible in the territory of the stenosed coronary artery in 9 of 11 patients before angioplasty and in 7 of 11 patients after angioplasty. The image quality was excellent in all studies. Thus this study shows that performing dynamic imaging with intracoronary injection of technetium 99m teboroxime is feasible. This technique may be useful to study the impact of angioplasty on coronary flow and tracer kinetics.

Endoscopy versus endoscopic ultrasonography in staging reflux esophagitis.

Precise staging of reflux esophagitis is very important for therapeutic decisions; in fact, chronic gastroesophageal reflux may cause transmural inflammation that leads to fibrosis with loss of esophageal wall compliance. In reflux esophagitis, endoscopic stating is limited to mucosal injury, while endoscopic ultrasonography (EUS) is able to visualize changes in the layer structure and localized or diffuse thickenings of the esophageal wall. In order to evaluate the usefulness of EUS in reflux esophagitis, a prospective study of 31 patients and ten normal subjects was performed. Endoscopic reflux esophagitis was staged as: E1 (erythema, n = 7), E2 (erosions, n = 13), E3 (ulcers, n = 11). EUS findings were recorded and evaluated at five different levels, starting from the gastroesophageal junction, using a quantitative method, the center line method. With this method, the sectorial and mean thickness, and area were calculated for each level. There was a significant difference between patients with reflux esophagitis and normal subjects in our study. E3 patients showed a significant upward involvement of the wall far from the visible lesions. Mild esophagitis may also cause esophageal wall thickening, involving even the entire wall. There was no correlation between the onset time of symptoms and the degree of thickening. In conclusion, EUS seems to be an important supplement to endoscopy in staging reflux esophagitis, as the progression of the inflammation is not related to the endoscopic findings.