Alessandro Paoletti Perini

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).

A real-time three-dimensional echocardiographic validation of an intracardiac electrogram-based method for optimizing cardiac resynchronization therapy

Introduction: Although optimization of atrioventricular and interventricular delays has been demonstrated to improve hemodynamics in patients with cardiac resynchronization therapy (CRT), the required time‐consuming procedure discourages its use in clinical practice. Recently, a new method for CRT optimization based on the intracardiac electrogram (IEGM) detected by the implanted leads, has been developed. We evaluated the effectiveness of this method in improving left ventricular (LV) asynchrony and performance using real‐time 3D echocardiography (RT3DE).

CHADS2 and CHA2DS2-VASc scores to predict morbidity and mortality in heart failure patients candidates to cardiac resynchronization therapy

AIMS CHADS2 and CHA2DS2-VASc scores are pivotal in assessing the risk of stroke in atrial fibrillation patients, and were recently proved to predict hospitalizations and mortality in specific clinical settings. Aim of this study was to evaluate whether these scores could predict clinical outcomes [first hospitalization for heart failure (HF) and a combined event of HF hospitalization and death for any cause] in patients candidates to cardiac resynchronization therapy and implantable defibrillator (CRT-D). METHODS AND RESULTS In a retrospective multicentre Italian study, we enrolled 559 consecutive HF patients candidates to CRT-D, and we grouped them in three pre-specified risk classes: low (CHADS2/CHA2DS2-VASc 1-2), moderate (CHADS2/CHA2DS2-VASc 3-4), and high (CHADS2 5-6/CHA2DS2-VASc 5-8). All patients underwent regular follow-up at implanting centres every 6 months; data collection was extended till the 72th month of follow-up. At a median FU of 30 months, 143 patients (25.4%) were hospitalized for HF and 110 (19.5%) died. Event-free survival analysis showed a significant difference according to baseline CHADS2 and CHA2DS2-VASc scores (Log-Rank for HF P < 0.001 for CHADS2 and CHA2DS2-VASc; Log-Rank for combined end-point P = 0.001 for CHADS2, P < 0.001 for CHA2DS2-VASc). At multivariate analysis, independent predictors of endpoints were: previous atrial fibrillation (AF) or AF at implant, NYHA class, QRS duration and the CHA2DS2-VASc score (for HF hospitalization P = 0.013; for the combined event, P = 0.007), while the CHADS2 score was not independently associated with either the end-points. CONCLUSION In CRT-D patients, pre-implant CHA2DS2-VASc score is an independent predictor of major clinical events at 30-month follow-up.

Cardiac resynchronization therapy-defibrillator improves long-term survival compared with cardiac resynchronization therapy-pacemaker in patients with a class IA indication for cardiac resynchronization therapy: data from the Contak Italian Registry

AIMS In candidates for cardiac resynchronization therapy (CRT), the choice between pacemaker (CRT-P) and defibrillator (CRT-D) implantation is still debated. We compared the long-term prognosis of patients who received CRT-D or CRT-P according to class IA recommendations of the European Society of Cardiology (ESC) and who were enrolled in a multicentre prospective registry. METHODS AND RESULTS A total of 620 heart failure patients underwent successful implantation of a CRT device and were enrolled in the Contak Italian Registry. This analysis included 266 patients who received a CRT-D and 108 who received a CRT-P according to class IA ESC indications. Their survival status was verified after a median follow-up of 55 months. During follow-up, 73 CRT-D and 44 CRT-P patients died (rate 6.6 vs. 10.4%/year; log-rank test, P = 0.020). Patients receiving CRT-P were predominantly older, female, had no history of life-threatening ventricular arrhythmias, and more frequently presented non-ischaemic aetiology of heart failure, longer QRS durations, and worse renal function. However, the only independent predictor of death from any cause was the use of CRT-P (hazard ratio, 1.97; 95% confidence interval, 1.21-3.16; P = 0.007). CONCLUSION The implantation of CRT-D, rather than CRT-P, may be preferable in patients presenting with current class IA ESC indications for CRT. Indeed, CRT-D resulted in greater long-term survival and was independently associated with a better prognosis.

Cardiac resynchronization therapy: the issue of non-response

Cardiac resynchronization therapy reduces mortality and morbidity in heart failure patients with wide QRS and severe impairment of left ventricular systolic function, who are symptomatic despite optimal medical therapy. However, a high percentage of patients fail to show clinical or echocardiographic response to this treatment. Beyond current selection criteria, other elements, such as QRS duration and morphology, concomitant medical therapy, degree of right ventricle dysfunction, myocardial viability, presence of left ventricular dyssynchrony, and associated renal dysfunction, play a crucial role in modulating the response to cardiac resynchronization. Consequently, they should be part of the standard pre-implant evaluation, as they could be used to identify patients who are very unlikely to be responders.

Hybrid Procedure (Endo/Epicardial) versus Standard Manual Ablation in Patients Undergoing Ablation of Longstanding Persistent Atrial Fibrillation: Results from a Single Center

Ablation of longstanding persistent atrial fibrillation (LSPAF) is the most challenging procedure in the treatment of AF, either by surgical or by percutaneous approach.

Echocardiographic and biohumoral characteristics in patients with AL and TTR amyloidosis at diagnosis

Few studies have analyzed the clinical and echocardiographic differences between light‐chain (AL) and transthyretin (TTR) amyloidosis.

Real-time 3-dimensional transthoracic echocardiography improves the diagnosis of isolated ventricular noncompaction.

In a 26-year-old man, an echocardiographic examination was performed for recurrent episodes of syncope. He had no familial history of cardiovascular diseases or sudden cardiac death. Traditional standard 2-dimensional (2D) echocardiography showed left ventricular (LV) dilatation with prominent trabeculations and diffuse contractility impairment (ejection fraction, 0.35) (Figure 1). Although the presence of isolated ventricular noncompaction of the myocardium (IVNC) was suspected, such findings did not fulfill the established criteria for the diagnosis as proposed by Jenni et al. 1 When transthoracic real-time 3-dimensional echocardiography (RT3DE) was performed with a model sonography system (IE33RD; Philips Medical Systems, Bothell, WA), a thickened myocardium with extensive trabeculations of both ventricles, especially in the LV apical and midventricular areas of both the inferior and lateral segments, clearly appeared, and the typical 2-layered structure of the myocardium was disclosed, with a thin, compacted outer band and a much thicker, noncompacted inner layer. The maximal end-systolic ratio of the noncompacted endocardial layer to the compacted myocardium was greater than 2 (Figure 2A). The 3-dimensional (3D) color images were able to denote the deep intertrabecular recess flow (Figure 2B). Thus, all the proposed diagnostic criteria for IVNC were fulfilled. Cardiac nuclear magnetic resonance (NMR) imaging subsequently performed confirmed the findings with the presence of extensive trabeculations and deep intratrabecular recesses involving the right ventricular apex and LV lateral and posterior walls, as shown on RT3DE (Figure 3).

Management of refractory atrial fibrillation post surgical ablation

Over the past two decades, invasive techniques to treat atrial fibrillation (AF) including catheter-based and surgical procedures have evolved along with our understanding of the pathophysiology of this arrhythmia. Surgical treatment of AF may be performed on patients undergoing cardiac surgery for other reasons (concomitant surgical ablation) or as a stand-alone procedure. Advances in technology and technique have made surgical intervention for AF more widespread. Despite improvements in outcome of both catheter-based and surgical treatment for AF, recurrence of atrial arrhythmias following initial invasive therapy may occur.Atrial arrhythmias may occur early or late in the post-operative course after surgical ablation. Early arrhythmias are generally treated with prompt electrical cardioversion with or without antiarrhythmic therapy and do not necessarily represent treatment failure. The mechanism of persistent or late occurring atrial arrhythmias is complex, and these arrhythmias may be resistant to antiarrhythmic drug therapy. The characterization and management of recurrent atrial arrhythmias following surgical ablation of AF are discussed below.

Echo/Doppler-derived time intervals are able to predict left ventricular reverse remodeling after cardiac resynchronization therapy.

Aim We evaluated the predictive value of echo/Doppler derived indices, which reflect the duration of the isovolumic phases of the cardiac cycle, in identifying cardiac resynchronization therapy (CRT) responders. Methods and results In 105 patients before and 6 months after CRT the following echo/Doppler parameters were evaluated: myocardial performance index (MPI) as the sum of isovolumic contraction time (IVCT) and isovolumic relaxation time (IVRT) divided by ejection time; total isovolumic time (t-IVT) as the sum of IVCT and IVRT divided by the RR interval; and standard deviation of the time to systolic peak velocity (Ts-SD) as asynchrony index. After 6 months, patients were defined responders according to 15% left ventricle (LV) end-systolic volume reduction or more. At baseline, responders (53.3%) had higher t-IVT and MPI than nonresponders (0.30 ± 0.06 versus 0.22 ± 0.05, P < 0.0001 and 1.01 ± 0.27 versus 0.73 ± 0.19, P < 0.0001, respectively). Receiving operating characteristic curve analysis showed that both t-IVT (80.3% sensitivity and 83.7% specificity, cut-off = 0.263) and MPI (78.6% sensitivity and 81.6% specificity, cut-off = 0.84) could predict CRT response. Baseline t-IVT correlated well to end-systolic volume reduction (r = −0.56, P < 0.00001). Conclusion Echo/Doppler derived indices, describing physiologic abnormalities of the isovolumic contraction and relaxation phase, are able to predict CRT-induced reverse remodeling.