Tiziana De Santo

Improving Stroke Risk Stratification Using the CHADS2 and CHA2DS2-VASc Risk Scores in Patients With Paroxysmal Atrial Fibrillation by Continuous Arrhythmia Burden Monitoring

Background and Purpose— In patients with atrial fibrillation (AF), stroke risk stratification schema do not consider AF parameters. The aim of the study is to assess the impact of combining risk factors with continuous AF burden monitoring. Methods— In this retrospective study 568 patients implanted with a DDDR-P pacemaker (AT-500; Medtronic) and a history of AF were continuously monitored for 1 year. Results— During follow-up, 14 patients (2.5%) had a thromboembolic event. Patients were divided into 3 groups: AF burden ⩽5 minutes per day (AF-free; n=223 [39%]), AF burden >5 minutes but <24 hours per day (AF-5 minutes; n=179 [32%]), and AF burden ≥24 hours (AF-24 hours; n=166 [29%]). Patients were also classified according to CHADS2 and CHA2DS2-VASc risk scores. The discrimination ability of each risk score was evaluated performing a logistic regression analysis and calculating the corresponding C-statistic. The addition of AF burden improved C-statistics: for CHADS2 from 0.653 (P=0.051) to 0.713 (P=0.007); for CHA2DS2-VASc, from 0.898 (P<0.0001) to 0.910 (P<0.0001). Conclusions— The CHA2DS2-VASc score had a high sensitivity to predict thromboembolism. Implementation of device data on AF presence/duration/burden has the potential to contribute to improved clinical risk stratification and should be tested prospectively.

Early and late outcome of treated patients referred for syncope to emergency department: the EGSYS 2 follow-up study

AIMS We evaluated the early (1 month) and late (2 years) death rate and syncopal relapses of patients referred for syncope to 11 general hospitals emergency departments. Patients were enrolled in the Evaluation of Guidelines in SYncope Study 2 (EGSYS 2) study. The guidelines of the European Society of Cardiology were strictly followed in the management of patients. METHODS AND RESULTS Out of the 465 patients enrolled in the EGSYS 2 study, 398 (86%) underwent a complete follow-up. We excluded 18 patients with non-syncopal attacks. Among the remaining 380 patients, death of any cause occurred in 35 (9.2%). The mean follow-up was 614 +/- 73 days. Six deaths (17% of total) occurred during the first month of follow-up. Patients who died were older, had a higher incidence of structural heart disease and/or abnormal ECG, had injuries related to syncope and higher EGSYS score. Syncope recurred in 63 (16.5%) patients. Syncopal relapses occurred in only one patient during the first month of follow-up. The incidence of syncopal recurrences was unrelated to the mechanism of syncope. No clinical differences were found between patients with or without syncopal recurrence and in patients with EGSYS score < or >or=3. CONCLUSION A peak of cardiovascular mortality but not of syncopal recurrences was observed in patients attending to the emergency department for syncope within the first month. Late unfavourable outcomes were caused by associated cardiovascular diseases rather than by the mechanism of syncope. The causes of syncope did not determine the recurrence rate.

Management of syncope: clinical and economic impact of a Syncope Unit

AIMS Aim of this observational study is to evaluate the clinical performance of a Syncope Unit, in order to assess whether the implemented organization really improves syncope management. METHODS AND RESULTS The study enrolled patients with unexplained syncope who were consecutively referred to our Syncope Unit, either as outpatients or during hospitalization, in a 2-month period. The design of this observational study consists in three phases: a retrospective analysis of their clinical management in the 9 months prior to the first attendance at the Syncope Unit (phase one), their subsequent clinical management in the Syncope Unit (phase two) and a 9-month follow-up (phase three). The retrospective analysis of phase one showed that 25% of patients had already been hospitalized without diagnosis. After Syncope Unit evaluation, diagnosis was obtained in 82% of patients, with 15% of patients indicated to pacing. In the follow-up, 23% of patients experienced a syncopal recurrence. Our analysis indicated an 85% reduction of hospital costs in the follow-up period. CONCLUSION The clinical and economic analysis of the three phases of our study demonstrates that a Syncope Unit allows an improved management of patients with syncope.

Heart rate variability monitored by the implanted device predicts response to CRT and long-term clinical outcome in patients with advanced heart failure

Few data exist on the long‐term changes and the prognostic value of heart rate variability (HRV) assessed by implanted devices in heart failure (HF) patients treated with resynchronization therapy (CRT).

Biventricular Upgrading in Patients with Conventional Pacing System and Congestive Heart Failure:Results and Response Predictors

Background: There are few studies on cardiac resynchronization therapy (CRT) in heart failure (HF) patients with preexisting right ventricular (RV) pacing. The purpose of this study was to determine the efficacy of CRT upgrading in RV‐paced patients and the predictivity of electromechanical dyssynchrony parameters (EDP) evaluated by standard echocardiography (ECHO) and tissue Doppler imaging (TDI).

Short-spaced dipole for managing phrenic nerve stimulation in patients with CRT: The “phrenic nerve mapping and stimulation EP” catheter study

BACKGROUND Phrenic nerve stimulation (PNS), occurring in 33%-37% of the patients with cardiac resynchronization therapy (CRT), is a limiting factor when implanting left ventricular (LV) leads from coronary veins. OBJECTIVE To test the hypothesis that PNS occurrence is related to bipolar electrode spacing. METHODS During standard CRT defibrillator implant procedures, a 5-F diagnostic electrophysiology catheter with 10 electrodes, spaced 2-5-2 mm, was positioned in a cardiac vein suitable for permanent LV lead placement. Pacing in the unipolar configuration identified the site with the lowest PNS threshold. PNS and left ventricular pacing (LVP) thresholds were then measured in different configurations at 0.5 ms: unipolar, each LV electrode served as the cathode in turn; and bipolar with different electrode spacing, cathode being the electrode with the lowest unipolar PNS threshold. RESULTS From February to September 2010, 40 patients undergoing CRT implantation were enrolled in 4 centers in Italy. It was possible to identify PNS and perform a complete set of measurements in 23 patients. A bipolar electrode spacing of 2 mm resulted in higher PNS thresholds in bipolar configurations han did a bipolar electrode spacing of ≥ 5 mm. However, no significant increase in the LVP threshold was observed (P = ns). CONCLUSIONS This experience suggests that LVP with a bipolar electrode spacing of 2 mm significantly increases the PNS threshold without affecting the LVP threshold, thereby increasing the possibility of delivering CRT when the LV lead is placed in proximity to the phrenic nerve.

Effect of bipolar electrode spacing on phrenic nerve stimulation and left ventricular pacing thresholds: an acute canine study.

Background— Phrenic nerve stimulation (PNS) is a common complication of cardiac resynchronization therapy when left ventricular (LV) pacing occurs via a coronary vein. The purpose of this study was to evaluate the effects of bipolar electrode spacing on PNS and LV pacing thresholds. Methods and Results— Electrophysiology catheters with standard (2 mm-5 mm-2 mm) or modified (1 mm-5 mm-1 mm) interelectrode spacing was, respectively, inserted in a posterior/lateral cardiac vein in a randomized order in 6 anesthetized dogs via jugular access. The phrenic nerve was dissected via a left minithoracotomy and repositioned over the vein as close as possible to one of the electrodes. The presence of PNS was verified (ie, PNS threshold <2 V at 0.5 ms in unipolar configuration). Bipolar pacing was delivered using the electrode closest to the phrenic nerve as the cathode, and multiple bipolar electrode spacing configurations were tested. During bipolar pacing, PNS threshold increased as bipolar electrode spacing was reduced (P<0.05), whereas LV pacing thresholds did not change significantly (P>0.05). Compared with a standard bipolar electrode spacing of 20 mm for LV leads, 1 and 2 mm bipolar electrode spacing resulted in a PNS threshold increase of 5.5±2.2 V (P=0.003) and 2.8±1.7 V (P<0.001), respectively. Similarly, PNS threshold increased by 6.5±3.7 V with 1 mm and by 3.8±1.9 V with 2 mm bipolar pacing (both P<0.001), compared with unipolar pacing. Conclusions— This study suggests that reducing LV bipolar electrode spacing from the standard 20 mm to 1 or 2 mm may significantly increase the PNS threshold without compromising LV pacing thresholds.

Impact of Mitral Regurgitation on the Outcome of Patients Treated with CRT-D: Data from the InSync ICD Italian Registry

Background: We assessed the influence of clinically significant mitral regurgitation (MR) on clinical‐echocardiographic response and outcome in heart failure (HF) patients treated with a biventricular defibrillator (cardiac resynchronization therapy defibrillator [CRT‐D]).

Effectiveness of cardiac resynchronization therapy in heart failure patients with valvular heart disease: comparison with patients affected by ischaemic heart disease or dilated cardiomyopathy. The InSync/InSync ICD Italian Registry

Aims To analyse the effectiveness of cardiac resynchronization therapy (CRT) in patients with valvular heart disease (a subset not specifically investigated in randomized controlled trials) in comparison with ischaemic heart disease or dilated cardiomyopathy patients. Methods and results Patients enrolled in a national registry were evaluated during a median follow-up of 16 months after CRT implant. Patients with valvular heart disease treated with CRT (n = 108) in comparison with ischaemic heart disease (n = 737) and dilated cardiomyopathy (n = 635) patients presented: (i) a higher prevalence of chronic atrial fibrillation, with atrioventricular node ablation performed in around half of the cases; (ii) a similar clinical and echocardiographic profile at baseline; (iii) a similar improvement of LVEF and a similar reduction in ventricular volumes at 6–12 months; (iv) a favourable clinical response at 12 months with an improvement of the clinical composite score similar to that occurring in patients with dilated cardiomyopathy and more pronounced than that observed in patients with ischaemic heart disease; (v) a long-term outcome, in term of freedom from death or heart transplantation, similar to patients affected by ischaemic heart disease and basically more severe than that of patients affected by dilated cardiomyopathy. Conclusion In ‘real world’ clinical practice, CRT appears to be effective also in patients with valvular heart disease. However, in this group of patients the outcome after CRT does not precisely overlap any of the two other groups of patients, for which much more data are currently available.

Is Dual Defibrillator Better than Conventional DDD Pacing in Brady-Tachy Syndrome? Results of the ICARUS Trial (Internal Cardioversion Antitachypacing and Prevention: Resource Utilization Study)

Aim of the study: To compare the impact of dual defibrillator versus conventional DDD pacing on quality of life and hospitalizations in patients with sinus node disease and recurrent symptomatic atrial fibrillation.Study design: Prospective, parallel, controlled trial.Methods: Sixty-three patients (41 M, mean age 71 ± 8 years) with sinus node disease and at least three symptomatic episodes of atrial fibrillation during the last year were enrolled. Thirty-one consecutive patients received a dual defibrillator (group A) and 32 standard DDD pacing (group B). In group A, 12 patients received an external remote-control device in order to shock themselves in case of atrial fibrillation, while 19 were scheduled for early in-hospital manual shock. Seventy-five percent had been hospitalized during the last year and 57% had required electrical cardioversion. Atrial fibrillation was persistent in 63.5% and paroxysmal in 37.5%. The follow-up lasted 1 year.Results: Atrial fibrillation recurred in 83.3% in group A and 79.3% in group B (p = ns). Electrical cardioversion was applied in 54.8% in group A and in 21.9% in group B (p < 0.05). On the whole, 89.5% of electrical cardioversions were delivered in the defibrillator group (p < 0.0001). In the whole population 27.0% patients had cardiac-related hospitalization (31.2% in the pacemaker group and 22.6% in the defibrillator group, p = n.s.). In patients with persistent atrial fibrillation, cardiac-related hospitalization rate was significantly lower in the group A (0% vs. 30%, p < 0.05). Considering Symptom Check List, symptoms significantly improved in the whole population, but symptom number and frequency improved significantly only in the group A. Similarly, SF-36 questionnaire scores showed a little higher quality of life improvement in the group A.Conclusions: Dual defibrillator showed consistent trends toward a higher effectiveness when compared with standard DDD pacing. Dual defibrillator was associated to reduced in-patient cardioversions and to better quality of life. All-cause hospitalizations were reduced only in patients with persistent atrial fibrillation