Does the Age Affect the Outcomes of Cardiac Resynchronization Therapy in Elderly Patients?

BACKGROUND: More and more heart failure (HF) patients aged ≥ 75 years undergo cardiac resynchronization therapy (CRT) device implantation, however the data regarding the outcomes and their predictors are scant. We investigated the mid- to long-term outcomes and their predictors in CRT patients aged ≥ 75 years. METHODS: Patients in the Cardiac Resynchronization Therapy Modular (CRT MORE) Registry were divided into three age-groups: <65 (group A), 65-74 (group B) and ≥75 years (group C). Mortality, hospitalization, and composite event rate were evaluated at 1 year and during long-term follow-up. RESULTS: Patients (n = 934) were distributed as follows: group A 242; group B 347; group C 345. On 12-month follow-up examination, 63% of patients ≥ 75 years displayed a positive clinical response. Mortality was significantly higher in patients ≥ 75 years than in the other two groups, although the rate of hospitalizations for HF worsening was similar to that of patients aged 65-74 (7 vs. 9.5%, respectively; p = 0.15). Independent predictors of death and of negative clinical response were age >80 years, chronic obstructive pulmonary disease (COPD) and chronic kidney disease (CKD). Over long-term follow-up (1020 days (IQR 680-1362)) mortality was higher in patients ≥ 75 years than in the other two groups. Hospitalization and composite event rates were similar in patients ≥ 75 years and those aged 65-74 (9 vs. 11.8%; p = 0.26, and 26.7 vs. 20.5%; p = 0.06). CONCLUSION: Positive clinical response and hospitalization rates do not differ between CRT recipients ≥ 75 years and those aged 65-74. However, age > 80 years, COPD and CKD are predictors of worse outcomes.

The stricter criteria for Class I CRT indication suggested by the 2016 ESC Guidelines reliably exclude patients with a worse prognosis in comparison with the 2013 ESC indication criteria.

BACKGROUND: The European Society of Cardiology (ESC) Guidelines published in 2016 modified indications for cardiac resynchronization therapy (CRT) in comparison with the 2013 ESC Guidelines. The aim of this analysis was to evaluate the impact of the stricter criteria suggested by the 2016 ESC Guidelines on patient outcome in a real-world population. METHODS: We collected data on 930 consecutive patients with complete outcome information who had undergone CRT implantation from 2011 to 2013 from the CRT-MORE registry. Patients were classified according to 2013 (Reference) and 2016 (Current) ESC Guidelines. The primary end-point of the study was death from any cause and heart failure hospitalization. RESULTS: According to the Reference Guidelines, 650 (69.9%) patients met Class I indications, 190 (20.4%) Class IIa, 39 (4.2%) Class IIb and 51 (5.5%) Class III. According to the Current Guidelines, 563 (60.5%) patients met Class I indications, 145 (15.6%) Class IIa, 108 (11.6%) Class IIb and 114 (12.3%) Class III. On comparing the Reference and Current Guidelines, the 538 patients who confirmed their Class I indication had a better outcome in terms of freedom from the combined end-point of heart failure (HF) hospitalization or death from any cause (hazard ratio (HR) of 0.64; 95% CI 0.42 to 0.99; p = 0.0436) when compared to the 112 patients who lost their class I indication (84 moved to class IIb and 28 moved to class III). CONCLUSIONS: The stricter criteria for Class I CRT indication suggested by the 2016 ESC Guidelines excluded about 20% of patients with a worse prognosis. CLINICAL TRIAL REGISTRATION: CRT MORE: Cardiac Resynchronization Therapy Modular Registry URL: http://clinicaltrials.gov/Identifier:NCT01573091.

Interlead anatomic and electrical distance predict outcome in CRT patients.

BACKGROUND: The implantation strategy appears to play a pivotal role in determining response to cardiac resynchronization therapy (CRT). OBJECTIVE: The aim of our study was to determine the association between anatomic and electrical interlead distance and clinical outcome after CRT implantation. METHODS: We included 216 first-time CRT recipients with left bundle branch block and sinus rhythm. On implantation, the electrical interlead distance (EID), defined as the time interval between spontaneous peak R waves detected at the right ventricular (RV) and left ventricular (LV) pacing sites, was measured. The anatomic distance between the RV and LV lead tips was determined on chest radiographs. RESULTS: The mean EID was 74 ± 41 ms, and the mean horizontal corrected interlead distance (HCID) was 125 ± 73 mm. After 12 months, 87 patients (40%) displayed an improvement in their clinical composite score. The cutoff values that best predicted an improved clinical status were as follows: 84 ms for EID (area under the curve 0.59; confidence interval [CI] 0.52-0.66; P = .026) and 90 mm for HCID (area under the curve 0.62; CI 0.55-0.69; P = .004). On multivariate analysis, only EID >84 ms (hazard ratio 0.36; CI 0.14-0.89; P = .028) and HCID >90 mm (hazard ratio 0.45; CI 0.23-0.90; P = .025) were significantly associated with the composite endpoint of death or cardiovascular hospitalization. In particular, the presence of both conditions (EID <84 ms and HCID <90 mm) was associated with the highest rate of events (log-rank test P = .002). CONCLUSIONS: The interlead anatomic and electrical distance are strongly and independently associated with patient outcome after CRT implantation. The 2 measures show an additive predictive value. (CRT MORE: Cardiac Resynchronization Therapy Modular Registry; www.clinicaltrials.gov, unique identifier: NCT01573091.)

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.

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.