Role of the left atrial function on the pseudonormalization of the transmitral flow velocity pattern evaluated by two-dimensional tissue tracking technique.

BACKGROUND: Mechanisms of the pseudonormalization (PN) of the transmitral flow (TMF) velocity pattern have been mainly attributed to left ventricular diastolic function. PURPOSE: To assess the influence of left atrial (LA) function on the PN with two-dimensional tissue tracking technique. METHODS: The subjects consisted of 21 healthy volunteers and 70 patients with various cardiac diseases. Images of one cardiac cycle in the apical four-chamber view were stored by the HIVISION 900 (Hitachi Medico, Chiba, Japan). The LA volume (LAV) loop was created using two-dimensional tissue tracking technique and LAV index (LAVI) at a given cardiac phase was calculated. A preload of 90mmHg was applied using a customized lower body positive pressure (LBPP) system. Patients were divided into the PN group (n=18) with their early diastolic TMF velocity (E) increased and late diastolic TMF velocity (A) decreased, and the non-(N)-PN group (n=52) with both E and A wave velocities increased by LBPP. RESULTS: (1) During LBPP, the LAVImax in both the groups increased significantly. (2) In the N-PN group, the LAVIpass (p<0.001), LAVIact (p<0.01), and LAVItotal (p<0.0001) increased significantly. The dV/dts (p<0.0001) and dV/dtE (p<0.0001) increased significantly with an increase in the dV/dtA. On the other hand, there was no change in those parameters except LAVIpass (p<0.05) and dV/dtE (p<0.05) significantly increased in the PN group. (3) As a result, the LAVImin was significantly greater in the PN group than in the N-PN group (p<0.0001) during LBPP. The ratio of E velocity to early diastolic mitral annular velocity (E/E') during LBPP was significantly greater in the PN group than in the N-PN group (p<0.0001). CONCLUSIONS: The lack of an increase in active LA emptying volume in response to an increase of preload leads to elevated LA pressure and the pseudonormalization of the TMF velocity pattern in patients with various cardiac diseases.

Significance of soluble CD40 ligand, adiponectin and reactive oxygen metabolites in aging.

We analyzed the association between platelet activation, adiponectin, insulin resistance and oxidative stress in aging. In addition, we included American football (AB) players to investigate whether this association is modulated by exercise. Eighty-six old age patients (> or = 65 years old) hospitalized at the nursing institution and 62 AB players were recruited as study subjects. Reactive oxygen metabolites (ROM), soluble CD40 ligand (sCD40L) and adiponectin were estimated with these patients. In comparison to old age, plasma adiponectin levels in AB players were significantly low. In addition, the adiponectin values of elder group (> 80 years) in old age were significantly increased higher than those for younger group (< or = 80 years). There were no differences of sCD40L in two groups. Levels of ROM in AB players were also significantly lower than that in old age. However, the ROM values of younger group in old age were significantly increased higher than those for elder group. The sCD40L also exhibited the same results. There were no significant differences in ROM and adiponectin levels between the high homeostasis model assessment-insulin resistance (HOMA-IR) (> 2.0) and the low HOMA-IR (< or = 2.0). In contrast, in the old age, the sCD40L and ROM levels in the high HOMA-IR group were significantly higher than those in the low HOMA-IR group. In addition, the adiponectin level in the high HOMA-IR group was significantly lower than that in the low HOMA-IR group. Our results suggest that platelet activation, adiponectin and oxidative stress are the very important factors for aging, and the maintenance of exercise could prevent the occurrence of metabolic syndrome or insulin resistance.

Electrocardiographic diagnosis of the coronary artery culprit site in ischemic heart disease.

The diagnostic accuracy of using electrocardiographic findings to identify affected vessels in cases of myocardial infarction and angina pectoris treated by percutaneous transluminal coronary angioplasty was assessed. From the anterior wall leads, ST segment elevation in leads I and aV(L) showed diagnostic accuracy (sensitivity, specificity and positive predictive value) in identifying proximal lesions of the left anterior descending coronary artery of 89%, 58% and 62%, and the diagnostic accuracy of the QS wave in V(1) was 62%, 83% and 72%, respectively. For the posterior wall leads, the corresponding values for the diagnosis of affected vessels based on R/S>1 in V(1) for the left circumflex coronary artery were 50%, 89% and 60%, respectively. The inferior wall leads with ST segment elevation in leads II, III and aV(F), and ST segment depression in aV(L), showed diagnostic accuracy for the right coronary artery of 90%, 90% and 92%, respectively. Bifurcation of the first diagonal branch, dominance of the posterior descending branch, the normal subtypes of the coronary artery and the occurrence of spontaneous recanalization may have influenced the accuracy of diagnosis. Adding a high lateral wall lead one intercostal space above V(4) and a posterior wall lead located one intercostal space below V(6) appeared to increase the diagnostic accuracy of detecting the coronary artery lesions responsible for myocardial ischemia.