Unlabelled: BACKGROUNDS AND METHODS: The opinions and the experience of Veneto practitioners about prevention of infective endocarditis were detected through a sample survey among the 386 practitioners of Health and Social Unit Nr 16, 17, and 36 of Veneto Region. The interview was carried out through a questionnaire, sent by mail, asking for: 1) general information on the practitioner's profession; 2) information about the previous experience in diagnosis and care of heart diseases, particularly of infective endocarditis, of atrial septal defect ostium secundum type without pulmonary hypertension, of unstable angina, and moderate mitral stenosis; 4) attitudes in the prevention of infective endocarditis. Of 386 practitioners surveyed, 186 (48.2%) responded. More than 60% of the responders held a diploma of specialization and 7% were cardiologists, half of the responders had worked in public hospitals. The 63.8% of the practitioners had patients over sixty in a percentage of 15-44%. In 1990 only 5.9% of the practitioners observed new cases of infective endocarditis, while half of them stated that some of their patients had suffered from this disease in the past., Results: The assessment of the level of severity for every heart disease is ranged between 0 (the minimum) and 10 (the maximum). The statistical analysis showed that the minimum arithmetic mean (+/- SD) is given for atrial septal defect without pulmonary hypertension with 4.6 +/- 2. Then for moderate mitral stenosis with 7.1 +/- 1.6, unstable angina pectoris with 7.4 +/- 2 and the maximum mean is given for infectious endocarditis with 8 +/- 1.7. ANOVA statistical analysis applied on the four paired series of assessment of severity carried out a high significant difference (F of Snedecor = 328.2; P < 0.001) among assessments, and among practitioners (F = 1.71; P < 0.01). High significant linear correlation (at least P < 0.01) is observed among the severity of the four heart diseases. Vice versa not significant association is showed between severity for every heart diseases and the experience of the interviewed., Conclusions: Most practitioners would prescribed prophylaxis for infective endocarditis to patients with rheumatic valve disease (91% of the responders), with previous episodes of infective endocarditis (90.4%), with prosthetic valve (67.6%) or with degenerative valve disease (57.3%). On the contrary most practitioners would not prescribe the prevention for infective endocarditis to patients with coronary heart disease (84.9%), with coronary bypass (71.4%), with mitral valve prolapse without insufficiency (60.6%), with dilatative cardiomyopathy (67%) or with obstructive cardiomyopathy (57.8%). A prevailing trend in case of congenital heart disease and mitral valve prolapse with insufficiency was not observed. The 86.6% of practitioners would prescribe the prophylaxis for infective endocarditis in case of dental extraction, but only the 64.4% would prescribe it in case of any potentially haemorrhagic oral or dental procedure. The 61.7% of the responders would not prescribe the prevention for infective endocarditis to patients receiving the prophylaxis for rheumatic fever. The practitioners would use in the following order: amoxicillin (77.3%), erythromycin (76.9%), penicillin V (76.3%) and ampicillin-gentamycin (61.3%). On the contrary, most responders would prescribe neither tetracycline (73%) nor spiramycin (69.8%). There is no prevailing trend to the employ of oral cephalosporins. The 90.3% of the practitioners think that infective endocarditis can be a quite interesting and useful subject for an up-to-date course.