[Echocardiographic study of valvular prosthesis]. / Estudio ecocardiográfico de las prótesis valvulares.

Eighty-six patients with valvular prosthesis (PV) were included in this study, 52 females and 34 males, from 9 to 55 years of age. The functional state of the PV was corroborated with catheterization, surgery or necropsy. The results of 92 PV were analyzed, of which 72 were in mitral position, including 49 dura mater valves (DMPV). In aortic position were 18, including 12 mechanical Bjork-Shilley (BS) and 2 in tricuspid position. The prostheses were classified in three groups: I. with regurgitation, II. with obstruction and III. without dysfunction. Of the 49 DMPV in mitral position 11 were in group I and 7 in group II. The echocardiogram revealed a diminished opening velocity in group II (255 +/- 41.2 mm/sec., P less than 0.001) as well as a diminished opening excursion (10.9 +/- 3.4 mm, P less than 0.02) and increased thickness of the leaflets (4.7 +/- 3.6 mm, P less than 0.05). Paradoxical interventricular septal movement was less frequent in group I (27.2%, P less than 0.05). Seventeen BS valves were in mitral position; of these 2 were classified in group I and the rest in group III, the opening velocity was increased (1200 mm/sec) in those of group I. None of the BS valves in aortic position were dysfunctional. No patients from group III died; mortality in groups I and II was 35%. In 5.1% of group III and 20% of groups I and II either no improvement or greater clinical deterioration was observed.

[Use of the temporary pacemaker in acute myocardial infarct]. / Uso de marcapaso transitorio en el infarto agudo del miocardio.

80 patients with acute myocardial infarction were analyzed in our coronary heart unit in whom the use of a transient pacemaker was indicated. The over all mortality was 33.75%, three fold the general myocardial infarction mortality in the CCU of the INCICH which is 12%, and increased to 51.35% in those with complete AV block. The mortality rate was even more significative with the association of RBBB and first degree AV block (80%). Cardiac failure was a fatal complication in 94% of that group of patients, and it increased to 100% in those with cardiogenic shock. Except those who progressed to complete AV block, there was not mortality in the patients with 2nd degree AV block. In the last mentioned group, predominated the posterior infarction with extension to the right ventricle and none had severe heart failure. The mortality rate was low in patients with recent LBBB or in those with RBBB associated to left branch hemiblock, but the majority had the disturbance permanently. In 7.5% of the patients implantation of a permanent pacemaker was necessary. In half of them due to the presence of a 3rd degree AV block of more than one moth duration. We conclude that the insertion of a temporary pacemaker in our cases had no major complications and the 12 accepted indications for this still hold on.