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Massimo Sassara

Publications and source records attributed to Massimo Sassara.

8 recordsLinked to original sources
PubMed2006

Role of ventricular Autocapture function in increasing longevity of DDDR pacemakers: a prospective study.

AIMS: Autocapture is an algorithm for automatic adaptation of ventricular output to capture threshold. The aim of this prospective study was to estimate the effects of ventricular Autocapture algorithm on DDD-DDDR pacemaker longevity. METHODS AND RESULTS: Eighty-three patients implanted with a DDD-DDDR pacemaker (Affinity or Entity; St Jude Medical, USA) were enrolled and the Autocapture function was activated pre-discharge. Ventricular pulse duration was randomly programmed at 0.3 or 0.4 ms, with a cross-over at 8-12 weeks and again at 13-14 months. Diagnostic data were retrieved from device memory and by calculating battery current drain from long-term threshold recordings; device longevity was estimated at the following settings: Autocapture with a pulse duration of 0.3 and 0.4 ms, respectively, standard output (3.5 V, 0.4 ms) and conventional low output programming (2.5 V, 0.4 ms). According to a series of assumptions, Autocapture was associated with a 55-60% increase in estimated device longevity compared with standard output programming and a 6-7% increase in longevity compared with low output programming. No significant differences were found between Autocapture programmed with a pulse duration of 0.3 or 0.4 ms. In projections to a 10-year follow-up, use of the Autocapture function resulted in a 42% reduction in pacing-related estimated costs compared with standard output programming at 3.5 V, 0.4 ms. CONCLUSION: Pacing with constant adaptation of ventricular output in dual-chamber devices has the potential to increase generator longevity and to reduce sizeably pacing-related costs compared with standard programming.

Adult↗
PubMed2006

Prediction of response to cardiac resynchronization therapy: the selection of candidates for CRT (SCART) study.

BACKGROUND: The aim of this study was to evaluate the ability of baseline clinical and echocardiographic parameters to predict a positive response to CRT. METHODS: We analyzed 6-month data from the first 133 consecutive patients enrolled in a multicenter prospective study. These patients had symptomatic heart failure (HF) refractory to pharmacological therapy (NYHA class II-IV), left ventricular ejection fraction (LVEF) < or =35%, and prespecified electrocardiographic, echocardiographic or tissue Doppler imaging markers of left ventricular (LV) dyssynchrony. RESULTS: After a follow-up period of 6 months, 1 patient died and 13 were hospitalized for worsening HF. There were significant (P < 0.01) clinical, functional, and echocardiographic improvements that included: New York heart Association Class, Quality-of-Life Score, QRS duration, LVEF, LV end-diastolic and end-systolic diameter (LVESD), and severity of mitral regurgitation A positive response was documented in 90/133 (68%) patients who presented an improved clinical composite score associated to an increase in LVEF > or = 5 units. A multivariate analysis identified that a smaller LVESD (OR = 0.957, 95% CI 0.920-0.996; P = 0.030) and longer interventricular mechanical delay (IVMD) (OR = 1.017, 95% CI 1.005-1.029, P = 0.007) as independent predictors of a positive response. Receiver-operating curve analysis showed that a positive response to CRT may be predicted in patients with IVMD > 44 ms (with a sensitivity of 66% and a specificity of 55%) or with LVESD < 60 mm (with a sensitivity of 66% and a specificity of 61%). CONCLUSIONS: Our results confirm the limited value of QRS duration in the selection of patients for CRT. A less-advanced stage of disease and echocardiographic evidence of interventricular dyssynchrony demonstrated to predict response to CRT, while intraventricular dyssynchrony did not predict response.

Aged↗
PubMed2004

[Cardiac resynchronization therapy for heart failure].

The short-term prognosis of advanced refractory heart failure is extremely poor and closely correlated with progressive left ventricular dysfunction. The identification of the negative effects of conduction delay on cardiac performance, observed in almost 50% of heart failure patients, disclosed a new research field addressing the correction of electrical abnormalities in order to achieve an improvement in myocardial function. Biventricular stimulation, or cardiac resynchronization therapy, corrects the atrioventricular, inter- and intraventricular mechanical asynchrony and, to date, is indicated (class IIA, level of evidence A) for patients with NYHA class III-IV refractory heart failure regardless of its etiology, QRS interval > or = 130 ms, left ventricular end-diastolic diameter > or = 55 mm, and ejection fraction < or = 35%. To date, the completed trials demonstrated in patients undergoing biventricular pacing a significant improvement in left ventricular performance, quality of life and NYHA class with no significant effects on total mortality. The identification of non-responders (approximately 20-30% of the patient population in completed trials) represents an unresolved issue of cardiac resynchronization therapy. Tissue Doppler imaging evaluation of left ventricular dyssynchrony, which is being addressed by non-randomized prospective studies, should drastically decrease the percentage of these patients.

Aged↗
PubMed2003

Long-term effectiveness of cardiac resynchronization therapy in patients with refractory heart failure and "narrow" QRS.

OBJECTIVES: The aim of the study was to evaluate the effectiveness of cardiac resynchronization therapy (CRT) in patients with refractory heart failure (HF) and incomplete left bundle branch block ("narrow" QRS), together with echocardiographic evidence of interventricular and intraventricular asynchrony. BACKGROUND: Cardiac resynchronization therapy has been proven effective in patients with HF and wide QRS by ameliorating contraction asynchrony. METHODS: Fifty-two patients with severe HF received biventricular pacing. The patients were eligible in the presence of echocardiographic evidence of interventricular and intraventricular asynchrony, regardless of QRS duration. The patient population was divided into group 1 (n = 38), with a QRS duration >120 ms, and group 2 (n = 14), with a QRS duration < or =120 ms. RESULTS: The baseline parameters considered in the study were similar in both groups. At follow-up, CRT determined narrowing of the QRS interval in the entire population and in group 1 (p < 0.001), whereas a small increase in QRS duration was observed in group 2 (p = NS); in all patients and within groups, we observed improvement of New York Heart Association functional class (p < 0.001 in all), left ventricular ejection fraction (p < 0.001 in all), left ventricular end-diastolic and end-systolic diameter (p < 0.05 within groups), mitral regurgitation area (p < 0.001 in all), interventricular delay (p < 0.001 in all), and deceleration time (group 1: p < 0.001, group 2: p < 0.05), with no significant difference between groups. The 6-min walking test improved in both groups (group 1: p < 0.001; group 2: p < 0.01). CONCLUSIONS: Cardiac resynchronization therapy determined clinical and functional benefit that was similar in patients with wide or "narrow" QRS. Cardiac resynchronization therapy may be helpful in patients with echocardiographic evidence of interventricular and intraventricular asynchrony and incomplete left bundle branch block.

Aged↗
PubMed2003

Functional and echocardiographic improvement following multisite biventricular pacing for congestive heart failure.

BACKGROUND: Heart failure remains a major cause of morbidity and mortality despite advances in pharmacological treatment. Recently, multisite biventricular pacing has been used in the treatment of patients with heart failure. OBJECTIVES AND METHODS: The short and medium term effects of this treatment modality were assessed, and the association between baseline clinical characteristics and the positive response to treatment was investigated. Consecutive patients who received this treatment modality were included. They underwent comprehensive clinical and echocardiographic assessment including a 6 min walk at baseline, one month and three months. RESULTS: Between January 1998 and June 1999, 95 patients received multisite biventricular pacing therapy in the three participating hospitals. In 63 patients with complete three-month follow-ups, there were improvements from baseline to three-month follow-up in New York Heart Association heart failure (3.3 +/- 0.5 to 2.2 +/- 0.6, P<0.001) and 6 min walk (305 +/- 120 to 403 +/- 113 m, P<0.001). Significant salutary changes in echocardiographic measurements were also observed in left ventricular (LV) diastolic dimension, ejection fractions (EFs), interventricular contraction delay and severity of mitral regurgitation (MR). The 63 patients were categorized into responders (n=42) and nonresponders (n=21) based on the clinical response. Clinical characteristics were similar between the two groups. The responders had a more pronounced decrease in QRS width. An increase in LVEF and a reduction in LV diastolic dimension, interventricular mechanical delay and severity of MR were observed in the responders but not in the nonresponders. Furthermore, there was a positive association between the reduction in QRS width and the increase in LVEF. CONCLUSIONS: Cardiac resynchronization by means of multisite pacing appears to be a promising therapy in the treatment of heart failure. The salutary clinical response is associated with echocardiographic improvement.

Aged↗
PubMedDate not supplied

Comparison of two different methods for the evaluation of left ventricular ejection fraction in patients with coronary artery disease.

The evaluation of left ventricular ejection fraction (LVEF) may be troublesome in difficult clinical settings in patients with coronary artery disease (CAD). The aim of this study was to compare 2 simple geometrical and nongeometrical methods of LVEF evaluation that could overcome the typical technical limitations of ultrasound examination. The authors studied 26 patients with proven CAD (63+/-10 years) who underwent left ventricular (LV) catheterization and coronary angiography during the hospital stay. A complete 2D-Doppler echocardiography was performed and LVEF was evaluated with the formula by Wyatt (W-LVEF), which relates the left ventricle to a biplane ellipsoidal figure, and by the myocardial performance index (MPI) formula (MPI-LVEF), MPI being an index of systodiastolic function. Mean MPI-LVEF was 41+/-8% and was significantly lower with respect to contrast angiography (52+/-14%, p = 0.0003) and to W-LVEF (49+/-13%, p = 0.0009). There was no statistically significant correlation between MPI-LVEF and geometric (either angiographic or ultrasound) LVEF. Bland-Altman analysis showed lack of agreement between MPI-LVEF and any other method evaluated in the study. MPI-LVEF may not be reliable and accurate for the evaluation of systolic function in patients with CAD. Nonetheless, the evaluation of global LV function by means of MPI may represent a valuable and affordable alternative to expensive and time-consuming methods, especially in the presence of difficult technical settings.

Cardiac Catheterization↗