Echocardiographic assessment of left ventricular dyssynchrony and correlation with QRS width in chronic heart failure

Echocardiographic parameters of mechanical dyssynchrony may improve patients selection for cardiac resynchronisation therapy in chronic heart failure. This study aimed to define the prevalence of inter, intra and atrio-ventricular dyssynchrony in heart failure patients with different QRS duration and to evaluate inter and intra-observer variability in collecting different echocardiographic dyssynchony parameters. Twenty patients with chronic heart failure of any origin, NYHA functional class II-III with LVEF < 40%, were evaluated by complete echocardiographic examination including tissue Doppler imaging [DTI] and Tissue Tracking. Three patients had an atrio-ventricular dyssynchrony with a mean left ventricular filling time to cardiac cycle of 33 +/- 5%. Six patients had an interventricular mechanical delay [IVMD] > 40 milliseconds, all of them had a QRS duration >/= 120 milliseconds. Overall, no statistically significant correlation was found between IVMD and QRS duration [r=0.35, p=0.4]. The mean septal to posterior wall-motion delay [SPWMD] was 83 +/- 64 ms. 7 patients had SPWMD >/= 130 ms. The baseline QRS duration did not correlate with SPWMD [p=0.7]. The mean LV dyssynchrony determined by deltaS-peak was 74 +/- 42 ms. Seven patients had LV dyssynchrony. Linear regression did not demonstrate a relation between QRS width and intraventricular dyssynchrony [p=0.34]. There was no concordance between intra-ventricular spatial or longitudinal dyssynchrony determined by DTI method and by Tissue Tracking [p=0.3 and 0.6 respectively]. The intraobserver reproducibility of LVFT/RR, IVMD and deltaS-peak [ICC= 0.99, 0.98 and 0.99, respectively], as well as the interobserver reproducibility [ICC: 0.96, 0.94 and 0.92, respectively], were very high. However, we observed a high variability for SPWMD measure [ICC=0.27, p=0.31]. Mechanical dyssynchrony did not correlate with QRS duration, despite the poor variability in collecting different echocardiographie parameters

[Cardiac amylodosis]

Amyloidosis is a rare infiltrative disease characterized by multiple clinical features. Various organs are involved and the cardiovascular system is a common target of amyloidosis. Cardiac involvement may occur with or without clinical manifestations and is considered as a major prognostic factor. To analyze the clinical features of cardiac involvement, to review actual knowledgement concerning echocardiographic diagnostic and to evaluate recent advances in treatment of the disease. An electronic search of the relevant literature was carried out using Medline and Pubmed. Keys words used for the final search were amyloidosis, cardiopathy and echocardiography. We considered for analysis reviews, studies and articles between 1990 and 2007. Amyloidosis represents 5 to 10% of non ischemic cardiomyopathies. Cardiac involvement is the first cause of restrictive cardiomyopathy which must be evoked. In front of every unexplained cardiopathy after the age of forty. The amyloid nature of cardiopathy is suggested if some manifestations were associated as a peripheral neuropathy, a carpal tunnel sydrome and proteinuria > 3g/day. Echocardiography shows dilated atria, a granular sparkling appearance of myocardium, diastolic dysfunction and thickened left ventricle contrasting with a low electric voltage. The proof of amyloidosis is brought by an extra-cardiac biopsy, the indications of endomyocardial biopsy are very limited. The identification of the amyloid nature of cardiopathy has a direct therapeutic implication: it indicates the use of digitalis, calcium channel blockers and beta-blockers. Today the treatment of amyloidosis remains very unsatisfactory especially in the cardiac involvement. An early diagnosis before the cardiac damage may facilitate therapy and improve prognosis