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Alfonso Roberto Martiniello

Publications and source records attributed to Alfonso Roberto Martiniello.

5 recordsLinked to original sources

Myocardial systolic activation delay in patients with left bundle branch block and either normal or impaired left ventricular function.

AIM OF THE STUDY: to evaluate determinants of myocardial activation delay of both left (LV) and right (RV) ventricle in patients with left bundle branch block (LBBB) and either normal or impaired LV ejection fraction (EF). METHODS: From an initial cohort of patients with LBBB, 42 patients with dilated cardiomyopathy (group A) and 33 with normal global LV systolic function (group B), all comparable in age and sex, underwent standard Doppler echo, pulsed Doppler myocardial imaging (DMI), and coronary angiography. Using DMI, the following regional parameters were evaluated in five different basal myocardial segments (LV anterior, inferior, septal, lateral walls-RV lateral wall): systolic (Sm), early- and late-diastolic (Em and Am) peak velocities. As index of myocardial systolic activation was calculated: precontraction time (PCTm) (from the beginning of Q-wave of ECG to the onset of Sm). Intraventricular systolic dyssynchrony was analyzed by difference of PCTm in different LV myocardial segments. Interventricular activation delay was calculated by the difference of PCTm between the most delayed LV segment and RV lateral wall. RESULTS: Patients of group A showed increased heart rate (HR), QRS duration and LV end-diastolic diameter, and reduced LV EF. By DMI, patients of group A showed reduced myocardial peak velocities and a significant intraventricular delay in activation of LV lateral wall, with increased regional PCTm (P < 0.001). In addition, patients with dilated cardiomyopathy showed a more pronounced interventricular dyssynchrony, even after adjustment for HR and QRS duration. By receiver operating characteristic (ROC) curve analysis, a cut-off value of 55 msec of interventricular delay showed 86% sensitivity and 92% specificity in identifying patients with impaired EF. In the overall population, by use of stepwise forward multivariate linear regression analyses, LV end-diastolic diameter (beta coefficient = 0.52; P < 0.001) and LV EF (beta coefficient =-0.58; P < 0.0001) were the only independent determinants of interventricular activation delay. CONCLUSIONS: Pulsed DMI is an effective noninvasive technique for assessing the severity of regional delay in activation of LV walls in patients with LBBB. The impairment of interventricular systolic sychronicity is strongly related to LV dilatation and to the degree of global systolic dysfunction. Therefore, patients with dilated cardiomyopathy suitable for cardiac resynchronization therapy may be better selected.

Bundle-Branch Block↗

Effects of volume loading on strain rate and tissue Doppler velocity imaging in patients with idiopathic dilated cardiomyopathy.

BACKGROUND: Strain rate is a promising echocardiographic technique which adds further information to that obtained with two-dimensional echocardiography and tissue Doppler imaging (TDI). The present study aimed to evaluate the effects of acute isotonic volume expansion on left ventricular function in patients with idiopathic dilated cardiomyopathy (DCM) utilizing TDI and strain rate measurements. METHODS: Ten patients with DCM and a left ventricular ejection fraction (LVEF) </= 40% underwent two-dimensional echocardiography during volume expansion (0.9% NaCl; 0.25 ml/kg/min for 120 min). Peak systolic tissue velocity and peak systolic strain rate were measured at baseline and at the end of volume loading. RESULTS: Mean LVEF was 32 +/- 9% at baseline and remained unchanged after volume loading. Similarly, peak systolic velocity was 2.21 cm/s at baseline and remained unchanged after volume expansion. By contrast, peak systolic strain rate significantly reduced from -1.08 +/- 0.37/s to -0.76 +/- 0.12/s (P < 0.05). CONCLUSIONS: In patients with DCM, peak systolic strain rate significantly reduces with volume loading in the absence of change in LVEF or peak systolic velocities at TDI. Because strain rate is a relative load-independent index of systolic function, the reduction observed is probably related to the decrease in left ventricular systolic performance that follows volume loading in heart failure patients. Thus, peak systolic strain rate appears to be more useful than TDI velocities to evaluate left ventricular dynamics during volume loading in patients with depressed left ventricular function.

Adult↗

Assessment of accessory atrioventricular pathways by Doppler myocardial imaging.

PURPOSE: The use of electrophysiologic studies (EPS) for the localization of accessory atrioventricular connections in Wolff-Parkinson-White syndrome (WPW) requires accurate evaluation of the site of bypass tract insertion. Doppler myocardial imaging (DMI) is a new ultrasound technique that allows the detection of abnormal and early regional myocardial depolarization. The purpose of this study was to identify an abnormal pathway site in WPW patients. METHODS: Twenty-one patients with ventricular preexcitation were studied by DMI. Two-dimensional color DMI, velocity maps, acceleration maps, and pulsed-wave applications were used. A subsequent diagnostic EPS was performed. The results of EPS were taken as the gold standard diagnostic procedure. Radiofrequency catheter ablation therapy was then performed on all patients. RESULTS: The anomalous pathway was detected by DMI in 16 (76%) of 21 patients (9 [90%] of 10 with left pathways and 7 [64%] of 11 with right pathways), with respect to results of the EPS. Pathway detection was better with pulsed-wave DMI (76%) with its higher temporal resolution as compared with M-mode velocity map (57%) and acceleration map (47%). In most of the patients with successful radiofrequency ablation, an immediate resolution of the abnormal ventricular depolarization occurred and was detectable by DMI. CONCLUSIONS: Our findings demonstrate the feasibility of DMI to assess the early ventricular contraction associated with atrioventricular accessory pathways. Therefore, DMI appears to be a clinically useful adjunct to noninvasive evaluation of abnormal myocardial depolarization in WPW and to evaluate the results after radiofrequency ablation, even though its accuracy is considerably better for left-sided accessory pathways than for right-sided ones.

Adult↗

[Mitral stenosis: echocardiographic evaluation].

The diagnostic tools available for the evaluation of mitral stenosis are two-dimensional and Doppler echocardiography, which are able to identify morphologic and flow changes. Two-dimensional echocardiography can be used to assess the morphological appearance of the mitral valve apparatus, including its mobility and thickness and the presence of calcified leaflets and subvalvular fusion. Wilkins'score permits evaluation of each variable which, on the basis of its severity, is scored according to a point system ranging from 1 to 4. In patients with severe mitral stenosis, a low total score (< 8) and elastic symmetric commissures suggest valvuloplasty. A total score > 10 and the presence of more than mild mitral regurgitation or of calcification of both commissures suggest valvular replacement. The left atrial and ventricular chamber sizes and other associated valvular diseases can also be assessed at two-dimensional or Doppler echocardiography. The severity of obstruction can be assessed using two-dimensional and Doppler echocardiographic area (pressure half-time, proximal isovelocity surface area, continuity equation) and with the mean transmitral gradient measured using a continuous wave Doppler signal across the mitral valve. Valvuloplasty can also be performed in patients with a high score when surgery is contraindicated. During follow-up it is necessary to evaluate the area, the mean gradient, the right ventricular systolic pressure and the presence of a residual atrial septal defect and mitral regurgitation. Restenosis is diagnosed when the valve area decreases to 50% of that achieved during valvuloplasty or surgery.

Adult↗