Benefits of left ventricular endocardial pacing comparing failed implants and prior non-responders to conventional cardiac resynchronization therapy: A subanalysis from the ALSYNC study.

OBJECTIVE: Cardiac resynchronisation therapy (CRT) is limited by a substantial proportion of non-responders. Left ventricular endocardial pacing (LVEP) may offer enhanced possibility to deliver CRT in patients with a failed attempt at implantation and to improve clinical status of CRT non-responders. METHODS: The ALternate Site Cardiac ResYNChronisation (ALSYNC) study was a prospective, multi-centre cohort study that included 118 CRT patients with a successfully implanted endocardial left ventricular (LV) lead, including 90 failed coronary sinus (CS) implants and 28 prior non-responders who had worsened or unchanged heart failure status after at least 6 months of optimal conventional CRT therapy. RESULTS: Patients were followed for 19 ±â€¯9 months. At baseline, prior non-responders were sicker as evidenced by a larger LV end-diastolic diameter (70 ±â€¯12 vs 65 ±â€¯9 mm, p = .03) and a trend towards larger LV end-systolic volume index (LVESVi, 95 ±â€¯51 vs 74 ±â€¯39 ml/m2, p = .07), and were more frequently anti-coagulated (96% vs 72%, p = .008) despite similar history of atrial fibrillation (54% vs 51%, p = .83). At 6 months, LVEP significantly improved LV ejection fraction (2.3 ±â€¯7.5 and 8.6 ±â€¯10.0%), New York Heart Association Class (0.4 ±â€¯0.9 and 0.7 ±â€¯0.8), LVESVi (9 ±â€¯16 and 18 ±â€¯43 ml/m2), and six-minute walk test (56 ±â€¯73 and 54 ±â€¯92 m) in prior non-responders and failed CS implants, relative to baseline (all p < .05), respectively. LVESVi reduction ≥15% was seen in 47% of the prior non-responder patients and 57% of failed CS patients. CONCLUSION: These data suggest that a sizable proportion of CRT non-responders can improve by LVEP, though to a lesser extent than failed CS implants. Clinical trial registration-URL: http://www.clinicaltrials.gov. Unique identifier: NCT01277783.

Stricter criteria for left bundle branch block diagnosis do not improve response to CRT.

BACKGROUND: Cardiac resynchronization therapy (CRT) has proved to be effective in patients with heart failure and left bundle branch block (LBBB). Recently, new electrocardiography criteria have been proposed for the diagnosis of LBBB. These criteria are stricter than the current American Heart Association (AHA) criteria. We assessed the rate of echocardiographic response to CRT in patients with traditional LBBB versus patients who met the new criteria (strict LBBB). METHODS: Consecutive patients undergoing CRT were enrolled in the CRT MORE registry. Patients with no-LBBB QRS morphology according to AHA criteria, atrial fibrillation, right bundle branch block, and right ventricular pacing were excluded. Strict LBBB was defined as: QRS ≥ 140 ms for men and ≥130 ms for women, QS or rS in V1-V2, mid-QRS notching or slurring in ≥2 contiguous leads. Patients showing a relative decrease of ≥15% in left ventricular end-systolic volume (LVESV) at 12 months were defined as responders. RESULTS: Among 335 patients with LBBB, 131 (39%) had strict LBBB. Patients with and without strict LBBB showed comparable baseline characteristics, except for QRS duration (166 ± 20 ms vs 152 ± 25 ms, P < 0.001). On 12-month evaluation, 205 patients (61%) were responders; 85 of 131 (65%) had strict LBBB and 120 of 204 (59%) had traditional LBBB (P = 0.267). On multivariate analysis, a history of atrial fibrillation, larger LVESV, and the presence of mid-QRS notching in ≥1 lead (odds ratio 2.099; 95% confidence interval 1.061-4.152, P = 0.033) were independently associated with echocardiographic response. CONCLUSION: Stricter definition of LBBB did not improve response to CRT in comparison to the current AHA definition.

ALternate Site Cardiac ResYNChronization (ALSYNC): a prospective and multicentre study of left ventricular endocardial pacing for cardiac resynchronization therapy.

AIMS: The ALternate Site Cardiac ResYNChronization (ALSYNC) study evaluated the feasibility and safety of left ventricular endocardial pacing (LVEP) using a market-released pacing lead implanted via a single pectoral access by a novel atrial transseptal lead delivery system. METHODS AND RESULTS: ALSYNC was a prospective clinical investigation with a minimum of 12-month follow-up in 18 centres of cardiac resynchronization therapy (CRT)-indicated patients, who had failed or were unsuitable for conventional CRT. The ALSYNC system comprises the investigational lead delivery system and LVEP lead. Patients required warfarin therapy post-implant. The primary study objective was safety at 6-month follow-up, which was defined as freedom from complications related to the lead delivery system, implant procedure, or the lead ≥70%. The ALSYNC study enrolled 138 patients. The LVEP lead implant success rate was 89.4%. Freedom from complications meeting the definition of primary endpoint was 82.2% at 6 months (95% CI 75.6-88.8%). In the study, 14 transient ischaemic attacks (9 patients, 6.8%), 5 non-disabling strokes (5 patients, 3.8%), and 23 deaths (17.4%) were observed. No death was from a primary endpoint complication. At 6 months, the New York Heart Association class improved in 59% of patients, and 55% had LV end-systolic volume reduction of 15% or greater. Those patients enrolled after CRT non-response showed similar improvement with LVEP. CONCLUSIONS: The ALSYNC study demonstrates clinical feasibility, and provides an early indication of possible benefit and risk of LVEP. CLINICAL TRIAL: NCT01277783.

Emergent transvenous cardiac pacing using ultrasound guidance: a prospective study versus the standard fluoroscopy-guided procedure.

AIMS: To compare time to active pacing and complication rates associated with temporary transvenous pacemaker (TTVPM) insertion between a fully echo-guided approach of vein access and lead placement, and standard placement of TTVPM under fluoroscopic guidance. METHODS AND RESULTS: We performed a prospective single-center observational study enrolling all consecutive patients from 1 January 2008 to 31 December 2012 needing emergent TTVPM placement. According to personal experience and clinical setting, the operators could choose between a fully echo-guided approach of TTVPM placement through the jugular vein and a standard fluoro-guided approach through the femoral vein. Safety and efficacy endpoints were pre-specified, registered, and compared. A total of 113 patients were treated using the echo-guided approach, and 90 via the fluoro-guided approach. The two groups differed with regard to clinical setting at presentation: an acute coronary syndrome was more frequent in the fluoro-guided approach group (39.7% vs. 16.8%, p<0.001), whereas asystole was more frequent in the echo-guided approach group (9.7 vs. 0%). Median time from decision to active pacing was significantly shorter in the echo-guided approach group (22 vs. 43 minutes, p<0.01). The overall complication rates were significantly lower in the echo-guided approach group (15.0% vs. 28.8%, p 0.02), because of lower rates of infections (2.7% vs. 11.1%, p 0.02) and puncture-related hematomas (0 vs. 3.3%, p=0.08). There were no deaths related to TTVPM, but one heart perforation requiring emergent pericardiocentesis occurred in the fluoro-guided approach group. One pneumothorax treated conservatively occurred in the echo-guided approach group, while no differences were observed with regard to sustained tachyarrhythmias (1.8% vs. 2.2%) or malfunctions requiring reposition of the catheter (8.8 vs. 8.9%). Overall, complications delaying permanent pacemaker implant for >48 hours were observed less often in the echo-guided approach group (6.8 vs. 20.7%, p = 0.03). CONCLUSION: Echo-guided insertion of TTVPM through the jugular vein is a feasible and safe alternative to fluoroscopic guidance and may reduce complications and time to active pacing in patients who are not candidates for emergent cardiac catheterization.

[From the coronary care unit to the intensive cardiac care unit: the evolution of the Cardiovascular Department of a tertiary center]. / Dalla unità di cura coronarica alla terapia intensiva cardiologica: l'evoluzione del Dipartimento Cardiovascolare dell'Ospedale di Lecco.

BACKGROUND: Substantial changes have occurred over time in the diagnoses, procedures and characteristics of patients admitted to coronary care units (CCU). Following the introduction of cardiac surgery activity in our hospital in December 2009, the aim of this study was to evaluate the changes in activity, processes of care and outcomes of patients consecutively admitted to our CCU after the reorganization of the Cardiovascular Department. METHODS: All 1674 consecutive patients admitted to the CCU from January 2009 to December 2010 were enrolled in this retrospective registry. RESULTS: In 2010, the number of patients referred from other hospitals or wards significantly increased (from 17.2% to 28.3%; p<0.001). Significant was also the increase of patients with ST-elevation myocardial infarction (n=190 to n=230, p<0.001), shock (n=20 to n=50, p<0.001), pulmonary edema (n=47 to n=64, p<0.05), cardiac arrest (n=2 to n=8, p<0.05), aortic dissection (n=0 to n=12; p<0.001). Conversely, the number of patients admitted for acute coronary syndromes without ST-segment elevation and GRACE risk score <140 significantly decreased (n=169 to n=52, p<0.001). In parallel, a significant increase in the use of intra-aortic balloon pump (2.0% to 5.6%, p<0.001), continuous hemofiltration (0.3% to 3.1%, p>0.001), non-invasive ventilation (5.6% to 10.5%, p<0.001) and mechanical ventilation (0% to 4.1%, p<0.001) was observed. Intensive care devices were more frequently used in the subgroups affected by shock, acute coronary syndromes without ST-segment elevation and GRACE risk score >200, and heart failure. Interestingly, despite the increase in high-risk clinical conditions the intra-CCU mortality did not change (3.1 vs 2.9%). CONCLUSIONS: Patients admitted to the CCU have high-risk acute clinical conditions. A model based on the sharing of cardiological, cardiac anesthesiological and surgical expertise is effective in increasing admission appropriateness and improving standards of care in a short period of time.

Actions elicited during scheduled and unscheduled in-hospital follow-up of cardiac devices: results of the ATHENS multicentre registry.

AIM: The number of cardiac implantable electronic devices (CIEDs) is continuously growing and this translates into a high number of in-hospital follow-ups. This workload justifies the increasing popularity of remote monitoring systems for the follow-up of CIEDs. The ATHENS registry was designed to find out what actions are taken during in-hospital follow-up of CIEDs at 10 different centres in Northern Italy. METHODS AND RESULTS: Between 1 March 2010 and 30 June 2010, all patients who came to our centres for a follow-up of their CIEDs were enrolled in the registry. We defined as visit with an action (VWA) a follow-up that elicited an action in that patient. The primary endpoint was the prevalence of VWA on the whole population. The secondary endpoints were: prevalence of VWA on the pacemaker (PM) population; prevalence of VWA on the implantable cardioverter defibrillator (ICD) population; prevalence of VWA on the cardiac resynchronization therapy (CRT) population; predictors of VWA in univariate and multivariate analyses. A total of 3362 patients were recruited. The primary endpoint was reached in 762 patients, 22.8% of patients (95% CI 21.4-24.3). The prevalence of action was highest for CRT (29.8%), followed by PM (22.8%) and ICD (18.6%). In a multivariate model, the prevalence of action was higher for CRT, than for PM and was lowest for ICD and it was higher for unscheduled visits and first visits than for scheduled visits. CONCLUSIONS: Our registry demonstrates that 'some actions' are taken during about 20% of scheduled in-hospital follow-up of CIEDs. These data should encourage the use of remote follow-up systems.

An observational registry on efficacy and safety of the right ventricular outflow tract as a site for ICD leads: results of the EFFORT (EFFicacy Of Right ventricular outflow Tract as site for ICD leads) registry.

BACKGROUND: Although pacing from the right ventricular outflow tract (RVOT) has been shown to be safe and feasible in terms of sensing and pacing thresholds, its use as a site for implantable cardioverter defibrillator (ICD) leads is not common. This is probably due to physicians' concerns about defibrillation efficacy. To date, only one randomized trial, involving 87 enrolled patients, has evaluated this issue. OBJECTIVE: The aim of this observational study has been to compare safety (primary combined end point: efficacy of a 14-J shock in restoring sinus rhythm, R wave amplitude >4 mV and pacing threshold <1 V at 0.5 ms) and efficacy (in terms of effectiveness of a 14-J shock in restoring sinus rhythm after induction of VF, secondary end point) of two different sites for ICD lead positioning: RVOT and right ventricular apex (RVA). METHODS: The study involved 185 patients (153 males; aged 67 ± 10 years; range, 28-82 years). Site of implant was left to physician's decision. After implant, VF was induced with a 1-J shock over the T wave or--if this method was ineffective--with a 50-Hz burst, and a 14-J shock was tested in order to restore sinus rhythm. If this energy was ineffective, a second shock at 21 J was administered and--eventually--a 31-J shock followed--in case of inefficacy--by a 360-J biphasic external DC shock. Sensing and pacing thresholds were recorded in the database at implant, together with acute (within 3 days of implant) dislodgement rate. RESULTS: The combined primary end point was reached in 57 patients in the RVOT group (0.70%) and in 81 patients in the RVA group (0.79%). The 14-J shock was effective in 159 patients, 63 in the RVOT group (77%) and 86 in the RVA group (83%). Both the primary and the secondary end points are not statistically different. R wave amplitude was significantly lower in the RVOT group (10.9 ± 5.2 mV vs. 15.6 ± 6.4 mV, p < 0.0001), and pacing threshold at 0.5 ms was significantly higher (0.64 ± 0.25 V vs. 0.52 ± 0.20 V, p < 0.01), but these differences do not seem to have a clinical meaning, given that the lower values are well above the accepted limits in clinical practice. CONCLUSIONS: Efficacy and safety of ICD lead positioning in RVOT is comparable to RVA. Even if we observed statistically significant differences in sensing and pacing threshold, the clinical meaning of these differences is--in our opinion--irrelevant.

Atrial tachyarrhythmias in primary and secondary prevention ICD recipients: clinical and prognostic data.

BACKGROUND: Atrial fibrillation (AF) is the most common sustained arrhythmia encountered in clinical practice. The natural history of this disturbance and its effect on survival is still not known in patients with implantable cardioverter defibrillators (ICDs). METHODS AND RESULTS: Several controlled trials for both secondary and primary prevention of sudden death using ICDs have been published in literature, and meta-analysis of them provided useful clinical information on the outcome during the follow-up of this population. AF occurs in about 25% of the patients with secondary prevention indication for ICD implantation. The prevalence of AF in patients with primary prevention indication for ICD implantation is much more difficult to define; it seems to be higher in patients with left ventricular dysfunction due to nonischemic etiology (ranging from 15% to 25%), and is lower in patients with ischemic etiology (about 5-10%). However, data from clinical registries, which are expected to better reflect clinical practice than randomized trials, seem to show a substantial difference as compared to the latter ones. A history of AF episodes in patients with an ICD indication for both primary and secondary prevention is probably associated with a higher risk of death. This is particularly evident in secondary prevention in ICD recipients, while it is still controversial in patients who received an ICD for primary prevention, particularly when patients with nonischemic etiology of their left ventricular dysfunction are considered. In a population of patients implanted with an ICD, there are several other clinical factors (ejection fraction, New York Heart Association functional class, age) that can interfere with the risk of death much more than AF itself. CONCLUSIONS: Further large-scale registries are needed to further characterize the population receiving ICD implantation, assessing the course of risk of death with regard to clinical variables and to evaluate the degree of acceptance of trials in clinical practice.

Primary prevention of sudden cardiac death: indications for cardioverter-defibrillator implantation.

Sudden cardiac death accounts for 400,000 to 450,000 deaths annually in Europe and in the United States. In patients with previous life-threatening arrhythmia, several perspective, randomized, controlled studies have demonstrated that implantable cardioverter-defibrillator (ICD) therapy is superior to the best antiarrhythmic therapy in prolonging survival. Furthermore, in a stratified-risk population with coronary artery disease, left ventricular ejection fraction < or = 35%, non-sustained ventricular arrhythmias, and inducible ventricular tachycardia, the ICD supports the class I level of recommendation by the guidelines published in 1998. The American College of Cardiology, American Heart Association, and North American Society of Pacing and Electrophysiology have updated the 1998 guidelines on the implantation of arrhythmia devices including in a class IIa level of recommendation also patients with a previous Q wave myocardial infarction and left ventricular ejection fraction < or = 30%, independently of their arrhythmic risk profile. In the recent years several randomized studies assessed the role of ICD treatment for primary prevention of sudden cardiac death and total mortality reduction in high-risk groups of patients with ischemic and non-ischemic dilated cardiomyopathy, with special reference to those with heart failure and ventricular dysfunction. This article reviews those trials that have resulted in defining indications for ICD, and that will expand its use in the future.