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M Bobbio

Publications and source records attributed to M Bobbio.

At least 91 records · Page 5Linked to original sources
PubMed1989

[Long-term variability in unsustained ventricular arrhythmias: pharmacologic and pro-arrhythmic effect].

A 72% reduction in the number of premature ventricular complexes, a 75 and 65% reduction in pairs and repetitive forms, respectively, are commonly accepted criteria for the evaluation of the efficacy of short-term antiarrhythmic treatment. On the other hand, a three-to-ten fold increase in the frequency of premature ventricular complexes is considered as a proarrhythmic effect. The aim of this paper is to verify if these criteria can still be applied on a long-term basis. Twenty-eight subjects without a demonstrable underlying organic heart disease and 21 patients with stable chronic ischaemic heart disease were studied. All patients showed more than 30 premature ventricular complexes per hour during ambulatory electrocardiogram monitoring. The spontaneous long term variability of ventricular arrhythmias was evaluated by comparing the first of three consecutive 24-hour ambulatory ECGs at the beginning of the study with a 24-hour ECG monitoring at the end of a 24-month follow-up period. According to the previous criteria about 50% of patients showed a spontaneous reduction in the number of premature ventricular complexes (greater than 72%) mimicking a therapeutic effect if any drug had been given. The increase in ventricular arrhythmias mimicked a proarrhythmic effect in almost 10% of patients. This trend is substantially the same both in subjects without organic heart disease and in patients with chronic coronary artery disease. The results of this study demonstrate that the initially established criteria used to judge the efficacy or the proarrhythmic effect of a given drug cannot be relied upon on a long-term basis.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1989

Does post myocardial infarction rehabilitation prolong survival? A meta-analytic survey.

Cardiac rehabilitation undoubtedly helps post-myocardial infarction patients to feel better; however, it is under consideration whether or not it also prolongs their survival. Since 1972 several published studies have examined the role of physical rehabilitation in relation to patient survival after myocardial infarction. Eight randomized controlled trials were reviewed in order to compare the rate of events (total death, cardiac death, recurrence of non-fatal myocardial infarction) in the trained and untrained patient population. A tendency toward a positive training effect on survival was present in almost all trials; however, in only one study was the number of cardiac deaths shown to be significantly reduced in trained patients. The aim of this study was to use a quantitative analysis based on estimates of individual trials to evaluate the effect of post-myocardial infarction rehabilitation programs on survival. The analysis of pooled data revealed a significant decrease in total mortality (relative risk 0.68 with 95% confidence limits 0.53-0.86; p = 0.002), and cardiac mortality (relative risk 0.62 with 95% confidence limits 0.48-0.82; p less than 0.001). However, there was a non-significant increase in recurrences (relative risk 1.12 with 95% confidence limits 0.84-1.49; p = 0.45). These data are very similar to those found by another meta-analytic survey performed on a different set of published studies, i.e., odds risk for total death 0.76, for cardiac mortality 0.75 and for non-fatal myocardial infarction 1.15.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1989

[Comparison between Doppler CW and Duplex-Scanning in the assessment of silent peripheral vascular lesions in a population of ischemic heart disease patients].

A recent ultrasound technique, Duplex Scanning (D-S), endowed with significant sensitivity, specificity and accuracy has been used to screen atherosclerotic disease in subjects at risk. Within the context of a transverse investigation aimed at identifying the multi-district nature of atherosclerotic plaques, the sensitivity and specificity values and the concordance index of Doppler C.W. (D-CW) have been checked using the D-S in carotid districts as a reference test in 205 patients suffering from ischaemic cardiopathy, asymptomatic for carotid vasculopathy, aged between 45 and 55. 170 patients had the D-CW and the D-S in 340 carotid vessels. D-CW revealed atherosclerotic changes in 122 carotids (prevalence 36%) while the D-S in 119 districts (prevalence 35%) revealed plaques greater than simple thickening, of which 89 (26%) with stenosis less than 30% and 30 (9%) with stenosis greater than 30%. Of the latter, 25 were greater than 60% and 5 less than 60%: one of them provoked a stenosis greater than 75%, the limit beyond which the change becomes haemodynamically significant. D-CW showed 46% sensitivity, a specificity of 70% and a concordance percentage of 59% with respect to D-S. D-CW sensitivity proved apparently low as did the concordance percentage between C-CW and D-S. However, considering that the lesions encountered were prevalently all haemodynamically non-significant, these values may become acceptable.(ABSTRACT TRUNCATED AT 250 WORDS)

Coronary Artery Disease↗
PubMed1988

Comparative accuracy of clinical tests for diagnosis and prognosis of coronary artery disease.

The discriminant accuracy of 14 variables derived from clinical evaluation, cardiac fluoroscopy, exercise electrocardiography, thallium scintigraphy and radionuclide angiography was assessed with respect to the diagnosis of angiographic coronary artery disease (CAD) among 607 patients undergoing coronary angiography, and with respect to the prognosis of subsequent cardiac death or nonfatal infarction among 4,104 patients followed for 1 year after testing. Discriminant accuracy (quantified in terms of the area under a receiver-operating characteristic curve for each variable) ranged from 50 to 73% for diagnosis, and from 54 to 77% for prognosis. Although there was a great deal of variability from test to test, variables representing direct or indirect manifestations of myocardial ischemia tended to correlate better with prognosis. Thus, variables derived from radionuclide angiography and thallium scintigraphy tended to have more prognostic accuracy than diagnostic accuracy, while fluoroscopy tended to have more diagnostic accuracy than prognostic accuracy. The pattern associated with clinical evaluation and exercise electrocardiography was less discernable. Accordingly, the accuracy of noninvasive tests with respect to diagnosis and prognosis of CAD should be separately determined based on individual empiric observation.

Adult↗
PubMed1988

Physician perception of exercise electrocardiography as a prognostic test after acute myocardial infarction.

To determine how physicians interpret exercise electrocardiography with respect to prognosis after acute myocardial infarction (AMI), 29 cardiologists (all board certified) were presented a case history of a 50-year-old man with an uncomplicated AMI and asked to estimate the patient's risk of dying over the next year, the sensitivity and specificity of exercise electrocardiography with respect to 1-year mortality, and the patient's risk of dying given a positive and a negative test result. Each set of physician estimates did not differ from those derived from a review of the medical literature (difference not significant for each). Risk after the test was also calculated using the Bayes' theorem. Calculated versus estimated risks were compared after a negative (7 +/- 9 vs 11 +/- 11%) and a positive (27 +/- 22 vs 17 +/- 15%, differences not significant) test result. Estimated risks were more accurate for a negative result than for a positive one (89 +/- 10 vs 83 +/- 12%, p less than 0.001). Given a positive test result, 57% of the physicians recommended coronary angiography. However, their estimates of risk (30 +/- 23%) were not significantly different from the estimates of those physicians (14%) who recommended additional noninvasive testing (19 +/- 4%) or those (29%) who recommended medical therapy (28 +/- 26%) (difference not significant). Thus, cardiologists accurately estimated prognosis following AMI, but they were less accurate in assessing high risk than low risk, and their management decisions correlated poorly with their risk assessments.

Adult↗
PubMed1988

Protection of the heart by nifedipine cardioplegia during coronary artery surgery. A clinical-haemodynamic evaluation.

This study was undertaken to evaluate the myocardial preservation obtained by adding a Ca++ channel blocker, nifedipine, to cold potassium cardioplegia (4 mcg/Kg/L) in 24 patients undergoing coronary artery surgery. They were randomly divided into a treated (N) and a control (C) group. Significant differences between the two groups were noted in the cardiac arrest time (p less than 0.001), in the mechanical recovery mode (p less than 0.01) and in the inotropic support needed (p less than 0.01). Cardiac index increased significantly in group N but decreased in group C (p less than 0.01). Peripheral delta P/delta t and endocardial viability ratio (EVR) decreased in both groups. Coronary sinus and serum CK and CK-MB release were significantly lower in the treated group. ECG ischaemic changes occurred in 8 patients in group C but only in 1 case in group N (p less than 0.001). Arrhythmias occurred in 3 cases in group C (p less than 0.05). The incidence of perioperative myocardial infarction was not significant (2 cases in group C). These data suggest that nifedipine can protect the myocardial cell from ischaemic injury without depressing myocardial contractility or AV conduction.

Arrhythmias, Cardiac↗
PubMed1988

[Comparison of two-dimensional echocardiography, angiocardioscintigraphy and cineventriculography in the study of left ventricular wall motion in ischemic cardiopathy].

Thirty-two patients with non acute myocardial infarction (inferior in twenty, anterior in ten, anterior and inferior in two) were studied with contrast left ventriculography, two-dimensional echocardiography and radionuclide angiography to assess left ventricular wall motion. We adopted the CASS criteria for the standard left ventriculography, and the Mayo Clinic classification for the echocardiographic study. Radionuclide angiography studies were obtained in left anterior oblique view; the images were evaluated with the use of Walsh-Hadamard transform; the left ventricle was divided in basal and apical septal, apical, posterolateral, posterobasal and two central segments. We tried to correlate the findings of the three techniques both for single segments and larger regions made of contiguous segments. Left ventricular angiography and two-dimensional echocardiography showed a fair concordance for both anterobasal and posterolateral left ventricular wall, whereas for the septal, apical and posterolateral regions contrast and radionuclide angiography had the best correlation. Compared to left ventricular angiography two-dimensional echocardiography shows better sensitivity than radionuclide angiography; the latter is more specific in defining left ventricular wall motion. The two non invasive techniques are therefore helpful in the evaluation of wall motion and their role is complementary.

Cineradiography↗
PubMed1987

Long term results (15-30 years) of surgical repair of aortic coarctation.

The late outcome in 226 patients who survived surgical repair of aortic coarctation was assessed 15-30 years after operation. Twenty six patients died during the follow up mainly from causes related to surgical repair or to associated cardiovascular anomalies. The survival rates of patients operated on between the ages of four and 20 years are 97%, 97%, 92% at 10, 20, and 30 years after operation. For patients operated on after the age of 20 the corresponding rates are 93%, 85%, and 68%. This difference is statistically significant from the fifteenth year of follow up onwards. The survival of patients operated on before the age of 20 is not significantly different from that of a comparable general Italian population. Recoarctation occurred in only 8% of patients who had end to end anastomosis, whereas it occurred in 35% of those who had other types of operation. Two thirds of the patients were hypertensive at the last visit. The actuarial curve shows that blood pressure was normal in most patients 5-10 years after operation, but 30 years after coarctation repair only 32% of patients are expected to be normotensive. Thus early repair of aortic coarctation appears to improve long term survival. Intervention in older patients and when blood pressure is high seem to be the most important predictors of late hypertension.

Adolescent↗
PubMed1987

[Doppler study of porcine bioprosthesis at the mitral site].

Twenty-nine asymptomatic patients with porcine (9 Liotta, 8 Carpentier, 8 Hancock and 4 Xenomedica) mitral prosthesis without clinical findings of prosthetic dysfunction and with normal M-mode and two-dimensional echocardiography were studied with pulsed and continuous wave Doppler. The following parameters of prosthetic function were evaluated: 1) maximum velocity (Vmax); 2) mean pressure gradient; 3) pressure half-time (P 1/2 t); 4) functional prosthetic area or Doppler orifice area (DOA); 5) mitral prosthetic regurgitation (MR); 6) tricuspid regurgitation (TR), if associated. P 1/2 t reproducibility was tested. For the study of the bioprosthetic function the transducer was located in apical position with the best alignment between ultrasonic beam and flow direction in the apical four-chamber view. The best acoustic signal was the guide to an optimal Doppler recording, analyzed for calculations. In 26 patients without MR at Doppler examination Doppler data were as follows: Vmax 1.6 +/- 0.2 m/sec (1.2-2 m/sec); mean pressure gradient: 4.4 +/- 2.7 mmHg (1.4-13 mmHg); P 1/2 t = 94.2 +/- 19.8 msec (55-140 msec); DOA = 2.4 +/- 0.6 cm2 (1.5-4 cm2). Mild unsuspected MR was detected in 3 patients, but the other parameters did not differ from those of the other 26 patients. TR was found in 10 patients. The degree of reproducibility of P 1/2 t was 0.92. Only the P 1/2 t value was longer among Hancock and Liotta or Xenomedica bioprosthesis (p = 0.005). Furthermore P 1/2 t was longer in the patients with longer follow-up periods than in the others (p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1986

[Digitalis and sinus rhythm. An old question that is still current].

To study the efficacy of chronic digitalis therapy in patients with congestive heart failure and sinus rhythm, a bibliographic search was fulfilled. 12 clinical trials were found and analyzed from a clinical and methodological point of view. These studies have shown a discrepancy between the clinical and haemodynamic efficacy of the drug. Usually patients' symptoms don't improve as it should be expected from the haemodynamic data. It is possible and advisable to withdraw a chronic treatment in many stable patients without worsening the clinical conditions. However some methodological bias (research strategies, patient selections, follow-up analysis and clinical and haemodynamic criteria) seem to reduce the results' reliability. The old question of digitalis efficacy in sinus rhythm is still controversial: new inotropic drugs are appearing. The lesson from the digitalis controversy should be seriously considered in the clinical evaluation of these new therapeutic agents.

Clinical Trials as Topic↗
PubMed1985

[Control of the efficacy of anti-arrhythmia drug therapy with the ambulatory electrocardiogram. Proposal for a new analytical statistical model].

Ambulatory electrocardiography is used for evaluating antiarrhythmic drug effectiveness. Statistical methods based on the analysis of the number of ventricular ectopic beats are currently employed. These techniques are not useful to compare groups of patients with different therapies, due to the wide spontaneous variability of the ectopic beats. We propose a new statistical method, based on the likelihood function. The new method has been tested both retrospectively on 102 patients treated with different antiarrhythmic drugs and prospectively on 12 patients subjected to three consecutive control ambulatory electrocardiograms and to a fourth one after treatment with propafenone. This new statistical method was found to be useful for comparing therapeutic effectiveness between groups of patients, whereas the traditional quantitative methods are to be preferred when drug effectiveness is evaluated in the single patient.

Adrenergic beta-Antagonists↗
PubMed1984

[Which general practitioner requests cardiologic consultation?].

Since health care costs continue to rise, the Regions and the Local Health Boards needs to draw up their plans, and permanent training initiatives must be undertaken for physicians, it was decided to see if and which personal and professional characteristics influence primary physicians in their requests for cardiological consultation. It is, in fact, well known that the attitudes of doctors not only affect the health of the population, but also the cost of such health to the community. Assessment of calls for heart examinations on the part of general practitioners attached to a local health board showed that neither age nor sex, nor the fact of working solely for the health service, nor the number of patients on a doctor's panel made any appreciable difference with respect to cardiological consultations. It was noted, however, that doctors whose only activity consisted of general practice under the health service called for fewer consultations than their colleagues with other activities, and that older physicians measured blood pressure less frequently and tended to give shorter descriptions of their findings to the cardiologist. The survey tended to show that the decision to send a patient to a cardiologist was probably more influenced by the characteristics of his complaint and his condition, and the medical attendant's clinical and psychological convictions than on such factors as age, sex, number of persons looked after, and working solely for the general health service.

Age Factors↗