forgotten variable of shear stress in mitral annular calcification: whole blood viscosity

The aim of this research was to assess the relationship between mitral annular calcification [MAC] and whole blood viscosity [WBV]. A total of 184 patients with MAC and 133 patients without MAC were enrolled in the study. The WBV was calculated with a confirmed formulation using the hematocrit and total plasma protein at a low shear rate [LSR] and high shear rate [HSR]. Early diastolic mitral annular velocity [Ea] and late diastolic mitral annular velocity [Aa] were measured using pulse Doppler tissue echocardiography. Pearson's correlation analysis was performed to assess the relationship between WBV and mitral annular motion velocities. The effects of different variables on the occurrence of MAC were assessed in univar-iate and multivariate logistic regression analysis. In patients with MAC, WBV values were significantly higher at HSR [18.04 +/- 0.84 vs. 17.25 +/- 0.96 208 s[-1], p < 0.001] and at LSR [78.0 +/- 14.2 vs. 61.9 +/- 17.1 0.5 s[-1], p < 0.001]. The WBV atHSR and LSR were significantly correlated with Ea[r = -0.477, p < 0.001; r = -0.385, p < 0.001, respectively] and Aa[r = -0.544, p < 0.001; r = -0.323, p < 0.001, respectively]. Multivariate analysis showed that WBV of both shear rates was an independent predictor of MAC. Using the ROC curve, a cut-off value of 70.1 for WBV at LSR had a sensitivity of 83.7% and a specificity of 73.7% [AUC 0.785, p < 0.001] and a WBV cut-off value of 17.5 at HSR had a sensitivity of 79.6% and a specificity of 71.4% [AUC 0.761, p < 0.001] for the prediction of MAC Patients with MAC had significantly higher WBV, which independently predicted the presence of MAC. WBV had an inverse correlation with mitral annular motion velocities, indicating that a higher WBV may lead to greater limitation in annular motion and, thus, more calcification

Arrhythmogenic Noncompaction Cardiomyopathy: Is There an Echocardiographic Phenotypic Overlap of Two Distinct Cardiomyopathies?

The clinical diagnosis of right ventricular (RV) cardiomyopathies is often challenging. It is difficult to differentiate the isolated left ventricular (LV) noncompaction cardiomyopathy (NC) from biventricular NC or from coexisting arrhythmogenic ventricular cardiomyopathy (AC). There are currently few established morphologic criteria for the diagnosis other than RV dilation and presence of excessive regional trabeculation. The gross and microscopic changes suggest pathological similarities between, or coexistence of, RV-NC and AC. Therefore, the term arrhythmogenic right ventricular cardiomyopathy is somewhat misleading as isolated LV or biventricular involvement may be present and thus a broader term such as AC should be preferred. We describe an unusual case of AC associated with a NC in a 27-year-old man who had a history of permanent pacemaker 7 years ago due to second-degree atrioventricular block.