Massimo Sassara

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.

Cardiac resynchronization therapy : Gender related differences in left ventricular reverse remodeling

Cardiac resynchronization refers to pacing techniques that change the degree of atrial and ventricular electromechanical asynchrony in patients with major atrial and ventricular conduction disorders. Atrial and ventricular resynchronization is usually accomplished by pacing from more than one site in an electrical chamber--atrium or ventricle--and occasionally by stimulation at a single unconventional site. Resynchronization produces beneficial hemodynamic and antiarrhythmic effects by providing a more physiologic pattern of depolarization. Atrial resynchronization may prevent atrial fibrillation in selected patients with underlying bradycardia or interatrial block. Its antiarrhythmic effect in the absence of bradycardia is unclear. Ventricular resynchronization is of far greater clinical value than atrial resynchronization. Biventricular (or single-chamber left ventricular) pacing is beneficial for patients with congestive heart failure, severe left ventricular systolic dysfunction, dilated cardiomyopathy (either ischemic or idiopathic), and a major left-sided intraventricular conduction disorder, such as left bundle branch block. The change in electrical activation from resynchronization, which has no positive inotropic effect as such, is translated into mechanical improvement with a more coordinated left ventricular contraction. Several recent randomized trials and a number of observational studies have demonstrated the long-term effectiveness of ventricular resynchronization in the above group of patients. The high incidence of sudden death among these patients has encouraged ongoing clinical trials to evaluate the benefit of a system that combines biventricular pacing and cardioversion-defibrillation into a single implantable device.Aim: Gender related differences in epidemiology, treatment, and prognosis of heart failure (HF) have been reported. We examined the sex influence in patients treated with cardiac resynchronization therapy (CRT).

Persistent Atrial Fibrillation Worsens Heart Rate Variability, Activity and Heart Rate, as Shown by a Continuous Monitoring by Implantable Biventricular Pacemakers in Heart Failure Patients

Background: Atrial fibrillation (AF) induces loss of atrial contribution, heart rate irregularity, and fast ventricular rate.

Risk stratification of ischaemic patients with implantable cardioverter defibrillators by C-reactive protein and a multi-markers strategy: results of the CAMI-GUIDE study

AIMS Patients at risk of sudden cardiac death (SCD) after myocardial infarction (MI) can be offered therapy with implantable cardioverter defibrillators (ICDs). Whether plasma biomarkers can help risk stratify for SCD and ventricular arrhythmias (VT/VF) is unclear. METHODS AND RESULTS The primary objective of the CAMI-GUIDE study is to assess the predictive role of C-reactive protein for SCD or VT/VF in ischaemic patients with the ejection fraction <30% and ICDs. Secondary endpoints included all-cause mortality, hospitalizations, and death from heart failure. Additional analyses incorporated cystatin-C and NT-ProBNP in multi-marker approach for the prediction of adverse outcomes. A total of 300 patients were enrolled. All-cause mortality at 2 years was 22.6%, mortality from heart failure was 8.3%. Primary endpoint occurred in 17.3%. At a competing risk multivariable analysis adjusted for baseline variables, no significant difference in primary endpoint was found between patients with C-reactive protein ≤3 vs. >3 mg/L [heart rate (HR) 0.91 (0.50-1.64) P = 0.76], while C-reactive protein >3 mg/L was strongly associated with mortality due to heart failure [HR: 3.17 (1.54-6.54) P = 0.002]. NT-proBNP above median was significantly associated with the primary endpoint [adjusted HR: 1.46 (1.020-2.129) P = 0.042]. A risk function, including the three biomarkers, NYHA class and resting HR, allowed stratification of patient mortality risk from 5 to 50%. CONCLUSION C-reactive protein >3 mg/L is not associated with SCD or fast VT/VF, however, is a strong predictor of HF mortality. Biomarkers combined with clinical markers allow an excellent risk stratification of mortality at 2 years.

Long-term effectiveness of dual site left ventricular cardiac resynchronization therapy in a patient with congestive heart failure.

This article describes a case of cardiac resynchronization therapy (CRT) performed with dual site left ventricular pacing. The main clinical and functional long‐term results are in agreement with the most recent data regarding traditional CRT. Furthermore, this innovative pacing modality allowed optimal inter‐ and intraventricular resynchronization. (PACE 2004; 27[Pt. I]:805–807)

Prognostic role of post-infarction C-reactive protein in patients undergoing implantation of cardioverter-defibrillators: Design of the C-reactive protein Assessment after Myocardial Infarction to GUide Implantation of DEfibrillator (CAMI GUIDE) study

Background Patients at risk of sudden cardiac death (SCD) after myocardial infarction (MI) can currently be offered effective means of prevention, such as implantable cardioverter-defibrillators (ICD). However, predictors of SCD able to identify those patients who are at higher risk are still lacking. Whether C-reactive protein (CRP), a serum inflammatory marker with established prognostic accuracy after MI, can also be a predictor of SCD is unclear. Methods The CAMI GUIDE study is designed to evaluate the prognostic role of CRP in patients undergoing ICD implantation after MI according to MADIT II criteria (i.e. left ventricular ejection fraction ≤ 30%). CAMI GUIDE is a prospective observational study aimed at assessing the role of CRP in the risk-stratification of SCD after MI. CRP will be measured on the basis of a pre-specified cut-off value of 3 mg/l, before and 1 month after ICD implantation; clinical follow-up will last 24 months. The primary endpoint is the combined rate of SCD or fast ventricular tachycardia/ventricular fibrillation. Secondary endpoints will be total mortality, death due to acute coronary syndromes, death from pump failure, non-fatal MI, coronary revascularization, hospitalization for congestive heart failure or unstable angina and inappropriate ICD shocks. Twenty-four Italian centers will participate in enrolment of the 290 patients planned according to power analysis. Conclusions The CAMI GUIDE study will assess the predictive role of CRP in SCD in patients with previous MI undergoing ICD implantation. Its results will improve risk stratification, thereby enabling better-tailored and more cost-effective therapies to be undertaken in those patients whose need is greatest.

Results of the SCART study: selection of candidates for cardiac resynchronisation therapy.

Objective To prospectively determine whether prespecified electrocardiographic, echocardiographic and tissue Doppler imaging (TDI) selection criteria may predict a positive response to cardiac resynchronisation therapy (CRT). Methods In this multicentre, prospective, non-randomised study, 96 heart failure patients with New York Heart Association class III–IV symptoms, an ejection fraction of ≤35%, and at least one marker of ventricular dyssynchrony according to prespecified electrocardiographic, echocardiographic or TDI criteria were enrolled. The primary endpoint was an improvement in the clinical composite score at 6 months. Results At enrolment, 70 patients fulfilled the electrocardiographic criterion (QRS duration ≥150 ms), 77 patients showed echocardiographic signs of dyssynchrony, and 37 patients met the TDI dyssynchrony criteria. The overall responder rate was 78/96 (81%). In particular, the primary endpoint was reached in 68 patients who fulfilled the echocardiographic criteria as compared with 10 patients who did not (88 vs. 53%, P = 0.001). The patients who met the echocardiographic criteria showed a significant greater reduction in left ventricular end-systolic diameter (P = 0.029) and a higher improvement in quality of life (P = 0.017) than patients who did not. Neither electrocardiographic nor TDI criteria seemed to predict a positive response to CRT. Conclusions In our patient population, mechanical indexes of dyssynchrony as assessed by echocardiography appeared to identify CRT responders. Although TDI is useful for evaluating ventricular dyssynchrony after CRT, the prespecified TDI inclusion criteria adopted in this investigation did not increase the number of CRT responders.

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.

Acute Myocardial Infarction Shortly After a Normal Exercise Stress Test Case Reports

The authors describe 3 cases of AMI occurring shortly after a negative bicycle ergometer stress test. These cases represent an unfortunate but extremely rare complication of a relatively safe diagnostic procedure. The authors also focus on the pathogenesis of the ischemic event, which may be attributed either to intraplaque hemorrhage or to platelet aggregation, both exercise- induced. The prevalence of AMI in this paper (0.06%) is similar to the data described in literature.

Effectiveness of cardiac resynchronisation therapy in patients with echocardiographic evidence of mechanical dyssynchrony.

Objective Cardiac resynchronisation therapy has proven to be effective in refractory heart failure (HF) patients with QRS >120–130 ms. Therefore, the aim of our study was to verify the long-term effectiveness of cardiac resynchronisation therapy in HF patients with echocardiographic evidence of mechanical asynchrony regardless of QRS duration. Methods One hundred and six patients with New York Heart Association class II–IV HF and echocardiographic documentation of interventricular and intraventricular asynchrony underwent biventricular stimulation. A clinical and functional evaluation was performed at baseline, 1, 3, 6 months, and every 6 months thereafter. Results After a median follow-up of 16 months, a significant improvement was noted in ejection fraction, left ventricular diameters, mitral regurgitation jet area, interventricular and intraventricular echocardiographic indexes of asynchrony, and the 6-min walking distance (P < 0.001 for all). Death rates for all causes and for cardiac causes were 18.2 (95% confidence interval 12.8–25.9) and 13.5 (95% confidence interval 9.0–20.3) per 100 person-years, respectively. Patients in New York Heart Association class IV had an almost three-fold increase in risk of dying as compared to class II–III (hazard ratio 2.97, 95% confidence interval 1.30–6.79). Conclusions Interventricular and intraventricular asynchrony at echocardiography may be useful in identifying HF patients suitable for cardiac resynchronisation therapy, with results comparable to those obtained with QRS duration selection criteria.