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Biomedical subjects

A Biagini

Publications and source records attributed to A Biagini.

At least 73 records · Page 4Linked to original sources

Early assessment of coronary reserve after bypass surgery by dipyridamole transesophageal echocardiographic stress test.

The evaluation of coronary reserve within a few hours of aortocoronary bypass surgery could be of extreme utility for the follow-up or therapeutical management of these patients. In 11 men patients who underwent aortocoronary bypass surgery, a dipyridamole echocardiography stress test was carried out before (1 to 3 days), early after (68 to 130 minutes), and 1 week after surgery. The first and third tests were performed using a standard transthoracic approach, while the second was performed by a transesophageal approach. Dipyridamole was administered intravenously at a dose of 0.56 mg/kg body weight (low dose) and eventually adding 0.28 mg/kg body weight (high dose), always in the absence of antiischemic therapy. An arbitrary wall motion score (0 = eukinesia; 1 = hypokinesia; 2 = akinesia; 3 = dyskinesia) was assigned to the seven different myocardial regions in which the left ventricle was divided in order to have a semiquantitative score. Under basal conditions wall motion score per patient in the three series of tests did not change significantly (1.6, 1.4, and 1.5, respectively), while the mean score during dipyridamole administration showed significant differences (3.6, 1.9, and 1.9, respectively), indicative of the results obtained by surgical repair. The test, positive in all patients before surgery, showed wall motion abnormalities and ischemic ECG changes in two patients immediately after surgery by the transesophageal approach. One patient who had a normal basal contraction pattern and an abnormal response after the test developed in the following days a perioperative myocardial infarction, while a second patient in the follow-up period developed low-level effort angina.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Evaluation of in vivo morphological results of balloon mitral valvotomy.

Percutaneous valvotomy is now more often considered for the treatment of mitral stenosis in poor risk patients. The aim of this study was the evaluation of the morphological changes produced by a similar procedure on the mitral valves of nine nonconsecutive patients undergoing a mitral valve replacement because of calcific isolated or prevalent mitral stenosis. The mitral valve was dilated through the left atriotomy before the valve excision with the same balloon catheter used in the percutaneous procedure. The pathological condition of the valve had been studied before dilatation by means of doppler echocardiography, cardiac catheterization and a visual examination performed by the surgeon before insertion of the balloon. At that time, the orifice area was measured with a Hegar dilator. A new measurement was performed after one or two dilatations performed at a balloon pressure of 2.7 atm. After excision, the valve was examined, photographed and X-rays were taken for evaluation of valve calcification. The pre-dilatation mean mitral valve orifice area was 1.3 +/- 0.4 cm2 and after the procedure was 2.8 +/- 0.3 cm2. In only one patient did the orifice area, originally 2.4 cm2, not increase. There was only one fused and calcified commissure, the other was normal. Before dilatation, the two commissures were fused in 17/18 cases and in 9/18, calcified. After dilatation, 5/17 commissures were completely open (not all were calcified), 10/17 incompletely opened and 2/17 remained fused (one in the above-mentioned patient).(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

Evaluation of rate-responsive pacemakers by transesophageal Holter monitoring of spontaneous atrial rate.

One of the most important problems in rate responsive (RR) pacing is the clinical experimental evaluation of the reliability of various sensors. In particular, it is difficult to test their sensitivity and specificity during daily activity of the patients. Atrial rate, when present and normal, is the most physiological marker of metabolic requirements, but sometimes it is impossible to analyze the P wave in ventricular paced rhythm during routinely performed tests (e.g., ergometric test and 24-hour Holter monitoring). During various physical activities, we monitored atrial electrograms on an esophageal lead on the first channel of a standard Holter tape recorder; on the second channel a surface ECG lead was recorded. We selected 10 patients with high grade heart block and normal sinus node function paced in RR-VVI mode. RR pacing was obtained using various sensors (body activity, blood temperature, spike-T interval, minute ventilation). The good quality of recording allowed an easy evaluation of atrial and ventricular rates. In four cases an appropriate increase in heart rate was documented; sensitivity threshold and/or rate response slope were reprogrammed when indicated. The pacing rate of one patient did not parallel the atrial rate during walking only. In three cases, we observed a delay in the ventricular rate increase, with ventricular rate decreasing at peak exercise despite further atrial rate increase. In the last two patients, we observed inappropriate pacing response; pacing rate increased later and to a lower level than the atrial one. This new method is applied easily and appears reliable to evaluate the response of RR pacemakers to individual metabolic needs.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

Ultrafiltration: a rational treatment for heart failure.

Patients with late-stage congestive heart failure with significant fluid overload respond well to ultrafiltration. The response is relatively long-standing and includes enhanced responsiveness to diuretics. Ultrafiltration is simple and highly cost effective. Furthermore, it possesses many advantages over massive or drastic pharmacological therapy. In the following paper, we report our own experience and review the world literature.

Blood Volume↗

The contribution of ventricular tachyarrhythmias to the genesis of cardiac pain during transient myocardial ischaemia in patients with variant angina.

The 24-h ambulatory electrocardiograms of 15 patients with both variant angina and ischaemia-related arrhythmias were analyzed to correlate cardiac pain with the following variables: site, type, duration and magnitude of ECG changes, presence and type of arrhythmias and time of occurrence of ischaemic attacks during the 24-h. Apart from sublingual nitrate therapy, Holter monitoring was performed in the Coronary Care Unit (CCU), in the drug-free state in all patients. During a total of 79 days of monitoring, patients had 1385 ischaemic episodes, of which only 30% were painful. The site of ischaemia did not predict the occurrence of pain. Pain was more frequently associated with ST-segment elevation, longer ischaemic duration, increased time to peak ECG change, and greater ST-segment shift and arrhythmias. When the 259 attacks in association with ventricular arrhythmias were compared to the arrhythmia-free episodes, they were more frequently painful for the same duration and magnitude of ECG ischaemic changes. Furthermore, the complexity of arrhythmias increased the probability of cardiac pain. Most ischaemic episodes occurred at night and a decrease in the frequency of painful episodes (apart from those associated with arrhythmias) was apparent. Thus, in addition to electrocardiographic severity and duration of ischaemia, the presence of ventricular arrhythmias and the time of occurrence seem to influence pain perception during ischaemia.

Adult↗

Factors affecting regional pulmonary blood flow in chronic ischemic heart disease.

To assess the effect of left heart disease on pulmonary blood flow distribution, we measured mean pulmonary arterial and wedge pressures, cardiac output, pulmonary vascular resistance, pulmonary blood volume, and arterial oxygen tension before and after treatment in 13 patients with longstanding ischemic heart failure and pulmonary edema. Pulmonary edema was evaluated by a radiographic score, and regional lung perfusion was quantified on a lung scan by the upper to lower third ratio (U:L ratio) of pulmonary blood flow per unit of lung volume. In all cases, redistribution of lung perfusion toward the apical regions was observed; this pattern was not affected by treatment. After treatment, pulmonary vascular pressures, resistance, and edema were reduced, while pulmonary blood volume did not change. At this time, pulmonary vascular resistance showed a positive correlation with the U:L ratio (r = 0.78; P less than 0.01), whereas no correlation was observed between U:L ratio and wedge pressure, pulmonary edema, or arterial oxygen tension. Hence, redistribution of pulmonary blood flow, in these patients, reflects chronic structural vascular changes prevailing in the dependent lung regions.

Blood Volume↗

Improvement of walking distance in patients with intermittent claudication by chronic local therapy with isosorbide dinitrate ointment.

Isosorbide dinitrate ointment (100 mg tid) was directly applied to 30 male patients with stable, documented intermittent claudication on the areas where ischemic pain was experienced. The symptom-free distance walked (DWA) and the maximum distance reached (MDR) basally, after one, three, six, and twelve months were evaluated by means of treadmill stress tests (TSTs) (angle 0 degree-velocity constant/patient). After the basal TST, patients were randomly divided into two groups: placebo group and therapy group (double blind), and a further TST was administered one month later. DWA results were 74 +/- 8 m vs 297 +/- 83 m and MDR results were 163 +/- 22 m vs 506 +/- 86 m in the therapy group (basal vs one month TST: p less than .01) and 94 +/- 24 m vs 96 +/- 15 m and 232 +/- 53 m vs 183 +/- 26 m in the placebo group, respectively (basal vs one month TST: NS). Being confident that a significant placebo effect was absent, the authors opened the trial and treated all patients, repeating further TSTs at three, six, and twelve months. The following results were obtained: DWA was 84 +/- 13 m, 316 +/- 63 m, 374 +/- 55 m, and 452 +/- 61 m; and MDR was 197 +/- 29 m, 431 +/- 59 m, 514 +/- 57 m, and 547 +/- 59 m, respectively, in basal conditions and after three, six, and twelve months of treatment (p less than .01 for all the values for both DWA and MDR vs basal values).(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Topical↗

Bicycle ergometer and echocardiographic study in healthy subjects and patients with angina pectoris after administration of L-carnitine: semiautomatic computerized analysis of M-mode tracing.

The discovery tha carnitine takes an active part in the transportation of long-chain acyl residues across the inner mitochondrial membrane dates back to 1958. It has been shown experimentally tha a reduction in myocardial carnitine content takes place after 15-30 min of ischemia. L-carnitine was administered orally in doses of 3 g/day for 30 days to 16 subjects with effort-induced angina and to 14 healthy subjects. A bicycle ergometer exercise test revealed a 1.5 mm (mean) depression of the ST-T segment in the angina subjects after pharmacological wash-out and a 1 mm depression in the same subjects after carnitine treatment. M-code echocardiography showed positive changes in a number of ventricular function parameters in the angina subjects and also, to a lesser extent, in the healthy controls.

Adult↗

Findings from long-term electrocardiographic monitoring of patients with variant angina in a coronary care unit.

Eleven patients with frequent episodes of variant angina underwent 24-hour electrocardiographic monitoring in a coronary care unit for a total of 70 days to assess circadian variation in ischemic episodes and its correlation with circadian heart rate (HR) rhythm. In each patient a series of 4 to 13 consecutive days, in the absence of therapy, with 8 or more ischemic episodes per day were analyzed. Harmonic regression models were fitted to the hourly number of ischemic episodes and the hourly values of HR. Out of 54 days, with 8 or more episodes per day for a total of 1,357 episodes, a circadian rhythm was observed for 34 days (64%), in at least 1 day in all patients and during the entire period of observation in only 3. Its presence was independent of the number of episodes; the peak of periodic functions occurred at 2.9 +/- 2.7 AM. A cadian rhythm for HR was observed in 61 of the 70 days (87%), consistently in 7 patients; the nadir occurred at 2.4 +/- 1.5 AM; simultaneous cycling in HR and transient ischemia was found on 32 days. The intrapatient difference between the peak and the nadir of the ischemic and the HR function was, on average, 2.6 +/- 3.3 hours. Thus, a circadian rhythm of ischemic episodes was present in all patients although it was not consistently present; simultaneous occurrence of circadian variation in ischemic episodes and HR was observed only in 60% of the days with a sufficiently high number of attacks and when this occurred, a significant phase shift was observed; occasional loss of HR cycling was observed in some patients, without an apparent cause.

Adult↗

[Recording of signals in ambulatory electrocardiography].

The different techniques for the acquisition of electrocardiographic signal in ambulatory monitoring are described in this paper. Direct and, frequency modulation systems are explained in details with their relative advantages and disadvantages. The basis of digital sampling and real time analysis of ECG signals are also explained.

Electrocardiography↗

[Technical ambulatory ECG innovations in performance evaluation].

Evaluating the performances of the instrumentation for Ambulatory ECG (AECG) analysis is a need largely recognized by both manufacturers and users. The most generally accepted method is the beat-by-beat comparison with annotated data bases, representing the different ECG abnormalities. Available data bases are aimed at arrhythmias detection evaluation, while it is recognized that the AECG ST-T changes detection has a great relevance in the analysis of ischemic heart disease. A concerted action of the European Community on Ambulatory Monitoring has been approved for achieving a comprehensive reference standard for assessing the quality of AECG instrumentation. The European project has been concentrated on the problem of ST-T analysis. An annotated data base is being developed with the contribution of european experts. A pilot study has been performed for establishing the criteria related to the development and annotation; particularly the definition of significant ST-T changes has been established. The data base will include 2-hour double channel AECG records, which contain at least one ST-T episode. Each record is annotated beat by beat according to the established scheme, identifying arrhythmic beats, rhythm changes, ST-T changes and noisy segments. A coordinating center has been established for interacting with the participating groups and for performing the operations related to the generation and management of the data base. For the time being 14 Groups of 8 Countries are participating to the annotation of the data base. A minimum number of 100 records is planned within June 1988.

Algorithms↗

[Analysis of the spread of ambulatory electrocardiography in Italy].

The diffusion of ambulatory monitoring (AM) in Italy was evaluated by a questionnaire sent to 102 centers known to be active in this field. The 70 replays obtained constitute this report. In Italy the first center for AM was activated in 1970, thereafter many other new centers started with the maximal increase between 1978 and 1983. During 1985 these centers performed 36223 examinations (mean 517) with a great variability in the number of examinations performed per year: 11 centers performed greater than 1000 examinations a yr, 21 greater than 500 less than 1000 and 38 less than 500. This variability was independent by the number of recorders each center have (on average 4.78 per center) and by the number of personnel involved in the activity. Waiting list resulted to be 25 days on average (1.90) and 4.7 days were needed for the replay (1.20). The main complain resulted to be the difficulty to obtain in short period of time technical assistance. In the second part of the questionnaire more clinical questions were asked. AM resulted to be required the most for arrhythmias and ischemic heart disease whereas atypical chest pain, palpitations and lipothymia events were considered to be the major reasons for a negative examination. In conclusion our data allow to identify the clinical relevance of AM in Italy and its major applicants.

Arrhythmias, Cardiac↗

[Ambulatory electrocardiography in patients with angina pectoris].

In the diagnosis of ischemic heart disease, long-term ECG recording has several distinct advantages. It allows one to relate patient symptoms to cardiac disturbances and to detect asymptomatic events, reveals the possible ischemic genesis of arrhythmias, and it is the most suitable method to assess the acute and chronic effectiveness of treatment and the evolution of the disease. In spite of these advantages, Holter monitoring has several limitations: the analysis of a single lead, is responsible in most systems for the low sensitivity in detecting ischemia occurring in unexplored regions; the period of 24-48 hours may not be sufficient for screening patients due to the unpredictable spontaneous variability of the disease; a common standard of analysis is still lacking even if the European Communities concerted action in Ambulatory Monitoring could represent the solution to this problem. Nevertheless the role of Holter monitoring appears essential in the ambulatory screening of patients with suspected ischemia for a better characterization of patients with ascertained myocardial ischemia, and for the evaluation of treatment and of the evolution of the disease.

Angina Pectoris↗

Comparison of verapamil and propranolol therapy for angina pectoris at rest: a randomized, multiple-crossover, controlled trial in the coronary care unit.

The effects of oral verapamil (V), 400 mg/day, oral propranolol (P), 300 mg/day, and placebo were compared in 10 patients admitted to the coronary care unit because of frequent attacks of angina at rest. Testing was done according to a randomized, double-blind, multiple-crossover, placebo-controlled trial, consisting of 8 consecutive 48-hour treatment periods with V or P or placebo. Three patients had variant angina, 5 had episodes of both ST-segment elevation and depression and 2 had only ST-segment depression. One patient had no critical coronary stenoses, 1 had 1-vessel disease, 7 had 2-vessel disease and 1 had 3-vessel disease. Electrocardiographic monitoring and tape recording were continued during the 16 days of the trial. A total of 1,602 episodes of transient diagnostic ST shift were recorded during the trial (1,309 episodes of ST-segment elevation, 293 of ST-segment depression); 43% were painless. Mean blood levels of V and P at the end of the active phases were 161 +/- 89 and 120 +/- 45 ng/ml, respectively. In the group as a whole, the average number of diagnostic ischemic ST-segment shifts per 24 hours was significantly reduced relative to corresponding placebo periods during V (2.6 +/- 2.4 vs 11.9 +/- 8.6; p less than 0.01) but not during P treatment (11.9 +/- 8.6 vs 12.0 +/- 7.3). Similar statistically significant reductions were observed in the number of anginal attacks and nitroglycerin tablets consumed. Considering individual patients, V reduced ischemic episodes during both active phases in all patients, whereas P was effective only in 1.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Detection of spontaneous episodes in post-infarction angina. Comparison between CCU and Holter monitoring.

The objects of this study are: to evaluate the incidence of early post-infarction angina in patients who developed transmural infarction (Q-AMI) or sub-endocardial infarction (no Q-AMI) during hospitalization; to compare data obtained from patients monitored in Coronary Care Unit (CCU) with those obtained from Holter monitoring. The 107 patients under study (55 with Q-AMI and 52 with no Q-AMI) presented the acute event on average 7.4 and 5.1 days after admittance in the CCU, respectively. A history of angina was present in all except 1 patient with Q-AMI and in all with no Q-AMI. After AMI the angina disappeared in 22 of the patients with Q-AMI and in 31 with no Q-AMI, while it continued in 33 and 21 of these patients, respectively. Twenty-one patients underwent ECG recording according to the Holter technique while in CCU, for an average of 4.4 days before and 5.2 days after the onset of AMI. The comparative analysis of the results obtained from the CCU and from Holter monitoring shows that the CCU greatly underestimates the number of ischaemic episodes, even when pain is present (4.5 episodes per patient per day before AMI and 2 after, versus 13.7 and 6.8 with Holter monitoring). The number of ventricular arrhythmias also seemed lower when analysing data from CCU monitoring. These data demonstrate the importance of Holter monitoring, even in patients admitted to a CCU, for a precise evaluation of the ischaemic and arrhythmic phenomena.

Adult↗

In-hospital myocardial infarction. Pre-infarction features and their correlation with short-term prognosis.

A retrospective study of 107 patients who sustained an acute myocardial infarction (AMI) during hospitalization was undertaken to assess the early prognosis of Q wave AMI (55 patients, group 1) and no-Q wave AMI (52 patients, group 2). Forty-one patients in group 1 and 31 in group 2 had documented ischaemia at rest in the period preceding AMI. The incidence of pre-infarction ischaemic attacks was similar in Q wave AMI compared with non-Q wave AMI (average daily incidence per patient 3.1 +/- 4.3 vs 3.0 +/- 4.3). A 'crescendo' pattern of pre-infarction angina was rarely observed in both groups. The incidence of post-infarction ischaemia (documented in 28 patients of group 1 and in 28 of group 2) was greater, but not significantly, in group 2 (average daily incidence per patient 1.0 +/- 2.6 vs 1.4 +/- 3.2). All patients with pre-infarction ischaemia sustained infarction in the same territory. AMI in group 1 was always symptomatic while 12 AMIs in group 2 were totally asymptomatic. Fifty patients from group 1 and 27 from group 2 were on therapy while AMI developed. Twenty-one patients from group 1 showed life threatening arrhythmias (ventricular tachycardia, ventricular fibrillation, third degree AV block or asystole) during AMI; of these, 14 did not survive the arrhythmias; they all had signs of left ventricular failure. Only one patient from group 2 had runs of ventricular tachycardia, unrelated to AMI but during pre- and post-infarction ischaemia. The overall mortality rate of Q wave AMI was 29% while no deaths occurred in the non-Q wave AMI.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗