The Significance of Renal Function in Response to Cardiac Resynchronisation Therapy - A Piece of a Much Larger Puzzle.

BACKGROUND: Although cardiac resynchronisation therapy (CRT) is an important player in the treatment of patients with heart failure (HF), the proportion of CRT patients with no improvement in either echocardiographic or clinical parameters remains consistently high and accounts for about 30% despite meeting CRT implantation criteria. Furthermore, in patients suffering from HF, renal dysfunction accounts for as many as 30-60%. Accordingly, CRT may improve renal function inducing a systemic haemodynamic benefit leading to increased renal blood flow. OBJECTIVES: The aim of the present study was to evaluate the importance of renal function in response to resynchronisation therapy during a 12-month follow-up period. MATERIALS AND METHODS: The study consisted of 46 HF patients qualified for implantation of cardiac resynchronisation therapy defibrillator (CRT-D). A CRT responder is defined as a person without chronic HF exacerbations during observation whose physical efficiency has improved owing to the New York Heart Association (NYHA) class improvement ≥1. RESULTS: A statistically significant difference was noted between responders and non-responders regarding creatinine level at the 3rd month (p=0.04) and, particularly, at the 12th month (p=0.02) of follow-up (100±23 vs 139±78 µmol/l). Moreover, there was a remarkable difference between both study groups with regard to GFR CKD-EPI (glomerular filtration rate (GFR) assessed using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) formula) at the 6th (p=0.03) and 12th month (p=0.01) of follow-up. The reference values for initial creatinine concentrations (101 µmol/l) as well as GFR CKDEPI (63 ml/min/1.73m2) were empirically evaluated to predict favourable therapeutic CRT response. CONCLUSION: Predictive value of GFR CKD-EPI and creatinine concentration for a positive response to CRT was found relevant.

Clinical Usefulness of N-terminal Prohormone of Brain Natriuretic Peptide and High Sensitivity Troponin T in Patients with Heart Failure Undergoing Cardiac Resynchronization Therapy.

BACKGROUND: Cardiac resynchronization therapy (CRT) is a valuable intracardiac device--based treatment option for a subgroup of patients with advanced heart failure (HF) and QRS prolongation. However, still a significant proportion of patients do not benefit from CRT implantation, labeled as non-responders. OBJECTIVES: The aim of the present study was to evaluate the N-terminal prohormone of brain natriuretic peptide (NT-pro BNP) and high sensitivity troponin T (cTnThs) value as predictors of CRT response in a 12-month observation. MATERIALS AND METHODS: The study included 46 patients with HF and implanted CRT-D. Levels of NT-pro BNP and cTnThs were assessed during a 12 month follow up. RESULTS: 46 consecutive patients (76% men) with a mean age of 64±8 were observed for 12 months. The CRT response criteria was met by 26 patients (56,5%). A significant decline in the NT-pro BNP concentrations was documented in responders (p=0.001). Moreover, ΔNT-pro BNP by at least 579 pg/ml had high sensitivity and specificity for identifying the CRT responders. There were no statistically significant differences in the results of cTnThs between the two study groups. CONCLUSION: The relative change in the level of NT-pro BNP by at least 43,5% allows to identify the responders to CRT after 12 months of follow-up. Serial measurements of NT-pro BNP can be a valuable tool for monitoring the effectiveness of CRT.

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.