A comparative enzyme histochemical study of glucose metabolism in the conduction system of mammalian hearts.

A histochemical study of some enzymes of glucose metabolism was performed on the heart conduction system of rat, dog, rabbit, pig, calf and lamb. Histochemical activities revealed a higher rate of anaerobic metabolism and a lower rate of aerobic metabolism in the conducting cells in comparison with the working myocardial fibres. An increase of the histochemical activities from the atrioventricular node to the distal portions of bundle branches was noted. The importance of the high glycogen content and the high phosphorylase activity in the heart conduction system was discussed.

[Aneurysm of the left sinus of Valsalva with fistula in the right atrium. A case report]. / Aneurisma del seno di Valsalva sinistro con fistola in atrio destro. Considerazioni su un caso clinico.

A case of an aneurysm of the left sinus of Valsalva ruptured in the right atrium is reported. This anomaly was diagnosed in a 30 year old woman who had a continuous systo-diastolic murmur and no signs of cardiac failure. The diagnosis of aneurysm of the left sinus of Valsalva was been determined using 2-D echocardiography, Cardioangiography, in addition, enabled us to recognize the fistula which connected the left sinus of Valsalva with the right atrium. The rarity of this case is supported by two pieces of data: A) aneurysms of the left sinus of Valsalva are the rarest of the sinus of Valsalva aneurysms; B) generally the sinus of Valsalva aneurysms rupture into the adjacent cardiac cavities, while the anomalous fistolous conduits are quite uncommon. The case reported confirms that from an aneurysm of the sinus of Valsalva an atypical fistolous conduit may arise. This could be detected by cardioangiography. In addition echocardiography, is very important, at least as a preliminary examination, for the diagnosis of the sinus of Valsalva aneurysms.

[An echocardiographic study of patients with left bundle branch block]. / Studio ecocardiografico dei pazienti con blocco di branca sinistra.

24 patients (19 females and 5 males) between 45 and 81 years of age (average age 61.6) with chronic left bundle branch block and with no signs of reduced left ventricular function have been studied by M-Mode echocardiography. These patients have been split into three groups: A) pts. with normal indexes of left ventricular function and normal thickness of the left ventricular walls; B) pts. with normal indexes of left ventricular function and thickness of the interventricular septum at upper limits or increased; C) pts. with different cardiac pathologies but with no signs of reduced ventricular function. The contractility indexes and the motion of the interventricular septum in both the basal and the medial portion have been studied. The results did not show any important variation concerning the ventricular function compared to the normal values. The study of the septal motion pointed out, as a main feature of the left bundle branch block, a preejective posterior motion followed by: a) a normal posterior systolic motion of the interventricular septum, or b) a posterior systolic motion followed by a further posterior protodiastolic motion (delayed motion), or c) an anterior systolic and posterior diastolic motion (paradoxical motion). The alterations of the septal movement ranked in different degrees. The clearest alterations were peculiarly found in the patients of the first group. The patiens of the third group, besides, have shown the lightest alterations. The results allowed to deduce that patients with left bundle branch block can have both normal motion or alterations of the interventricular septum motion of different degree.(ABSTRACT TRUNCATED AT 250 WORDS)

[Echocardiography in the diagnosis of rupture of chordae tendineae. Description of a clinical case]. / L'ecocardiografia nella diagnosi di rottura di corda tendinea. Descrizione di un caso clinico.

A case of ruptured chordae tendineae is reported. The patient, a 53 year old man, had a crescendo-decrescendo holosystolic murmur, a third and a fourth heart sound, that is the typical auscultatory pattern of this lesion. However, M-mode and 2-D echocardiography had a permanent role in arriving at the diagnosis. M-mode echocardiography, in fact, showed a clear systolic flutter of the mitral valve and a large anterior diastolic motion of the posterior mitral leaflet; 2-D echo, besides, revealed a quick systolic motion into the left atrium of the tip of the posterior mitral leaflet and lack of coaptation of mitral leaflet during systole. The patient underwent an operation of valve repair. At the postoperative echocardiographic examination none of the features of flail posterior mitral leaflet were found. This fact can demonstrate the success of the operation.