Myocardial Scar on Surface ECG: Selvester Score, but Not Fragmentation, Predicts Response to CRT.

PURPOSE: Myocardial scar is directly related to the response to CRT after implantation. The extent of myocardial scar can be detected not only by cardiac magnetic resonance but also by two electrocardiographic scores: fragmented QRS (fQRS) and Selvester score (SSc). The aim of our study is to compare the role of baseline SSc and fQRS in predicting response to CRT in a cohort of heart failure patients with true left bundle branch block (LBBB). As a secondary endpoint, we assessed the association of both scores with overall and cardiac mortality, heart failure hospitalizations, ventricular arrhythmias requiring ICD intervention, and major adverse cardiovascular event (MACE). METHODS: We evaluated fQRS and SSc of 178 consecutive HF patients with severe systolic dysfunction (LVEF ≤ 35%), NYHA class II-III despite optimal medical treatment, and true-LBBB. Response to CRT was defined as the improvement of LVEF of at least 10% or as the reduction of LVESV of at least 15% at a 6-month follow-up. Each endpoint was related to fQRS and SSc. RESULTS: SSc ≥7 was significantly associated with the absence of echocardiographic response to CRT (OR: 0.327; 95% C.I. 0.155-0.689; p=0.003), while the presence of fQRS at baseline ECG was not (OR: 1.133; 95% C.I. 0.539-2.381; p=0.742). No correlation was found between SSc and overall mortality, cardiac death, ventricular arrhythmias, hospitalizations due to heart failure, or for MACE. Similar results were observed between fQRS and all secondary endpoints. CONCLUSION: In HF patients with true-LBBB and LVEF ≤35% eligible for CRT, myocardial scar assessed by calculating the SSc on preimplant ECG is an independent predictor of nonresponse after multiple adjustments. Neither SSc nor fQRS is associated with overall and cardiac death, ventricular arrhythmias, or hospitalization for heart failure at a 24-month follow-up.

Sleep-disordered breathing and effectiveness of cardiac resynchronization therapy in heart failure patients: gender differences?

OBJECTIVES: This study evaluated heart failure (HF) patients who underwent cardiac resynchronization therapy (CRT) and who had device-documented sleep-disordered breathing (SDB). We found gender differences in acute changes in SDB due to CRT impact. BACKGROUND: SDB typically occurs in HF patients. However, the role of SDB and its response to CRT in HF patients, as well as the relation with gender are currently not fully researched. METHODS: Among 63 consecutive patients who received CRT with an SDB algorithm, 23 patients documented SDB at one-month cardiac device interrogation and represented our population. We defined a Sleep apnoea Severity SCore(SSSC), and consequently, patients were categorized to have mild, moderate, and severe sleep apnoea syndrome divided into two groups: Group-1: 18 males (78%); Group-2: 5 females (22%). We evaluated the variation of apnoea burden and CRT response based on gender differences. RESULTS: A significantly higher proportion of patients in the male group were non-responders to CRT at 12-months follow-up (p = 0.076) while in the female population 5/5 patients (100%) were responders to CRT at the same follow-up time (p = 0.021). Among Group-2 subjects, we documented a significant linear decrease in SSSC(p > 0,01) while in Group-1 the CRT effect on SSSC was variable. At 12-months follow-up, the difference in SSSC between the two groups was statistically significant (p < 0.001). CONCLUSIONS: Our study reports a correlation between CRT response and sleep apnoea burden considering gender differences. In particular, HF-women responders to CRT demonstrate a significant linear decrease in sleep apnoea burden determined through a device algorithm, when compared to a similar male population. Further research is needed to confirm these findings.

Long-term outcomes after "Zero X-ray" arrhythmia ablation.

PURPOSE: Radiation exposure related to conventional tachyarrhythmia radiofrequency catheter ablation (RFCA) carries small but definite risk for both patients and operators. Today, non-fluoroscopic mapping systems enable to perform catheter ablation with minimal or zero fluoroscopy. The purpose of this study was to evaluate the long-term outcome of patients who had undergone "Zero X-ray" ablation, since no information is available on the very long-term benefits. METHODS: A total of 272 arrhythmias in 266 patients have been treated with catheter ablation by means of a zero-ray approach guided only by a nonconventional mapping system (EnSite NavX™, Ensite™ Velocity™ mapping system; subsequently Ensite™ Precision™ Abbott, St. Paul, MN). Fluoroscopy was never used. RESULTS: Over a period of 6 years, patients were followed up for an average of 2.9 ± 1.6 years. A 100% rate of acute success was observed in the study population, with a complication rate of 0.8%. Chronic success was achieved in 90.8% of the total number of procedures (272). Patients in whom the same arrhythmia recurred during follow-up underwent to a redo catheter ablation procedure in 60.0% of cases, while the remaining 40.0% underwent pharmacological treatment. A new post-ablation arrhythmia occurred in 7.7% of the sample. CONCLUSIONS: The non-fluoroscopic approach is a feasible and safe alternative to fluoroscopy for arrhythmias ablation. This method ensures low complications rates, high acute procedural success rates, and comparable long-term outcomes with clinical benefits for both patients and physicians. The complete elimination of fluoroscopy during catheter ablation is advantageous and does not reduce patient safety.

Ablation of recurrent malignant idiopathic ventricular tachycardia: When proper diagnosis and success is a matter of contact.

Effective and stable contact between the catheter tip and the tissue is crucial for both mapping and lesion formation during cardiac ablation procedures. Contact force catheter may be not only a therapeutic approach to arrhythmias, but also a tool for achieving accurate characterization of the arrhythmic substrate.

Simplified Selvester Score: a practical electrocardiographic instrument to predict response to CRT.

AIMS: To investigate the LBBB Selvester Scoring System (LBBB-SSc) and the Simplified-SSc prognostic impact in predicting response to CRT, all cause and cardiac mortality, heart failure (HF) hospitalizations and onset of arrhythmias in HF patients undergoing CRT. METHODS: We retrospectively evaluated LBBB-SSc and Simplified-SSc of 172 consecutive HF patients with true-LBBB who underwent CRT. Response to CRT was defined as the improvement of LVEF of at least 10% or as the reduction of LVESV of at least 15% at 6-month follow-up. Logistic regression analysis and Cox proportional hazard analysis were performed to evaluate each endpoint related risk according to LBBB-SSc and Simplified-SSc. RESULTS: The LBBB-SSc and the Simplified-SSc were inversely correlated with response to CRT. Myocardial scar at both scores was independently associated to non-response to CRT. No correlation was observed between LBBB-SSc or Simplified-SSc and other endpoints. CONCLUSIONS: In HF patients with true-LBBB, Simplified-SSc is able to predict response to CRT.

Metabolomic does not predict response to cardiac resynchronization therapy in patients with heart failure.

AIMS: Metabolomic, a systematic study of metabolites, may be a useful tool in understanding the pathological processes that underlie the occurrence and progression of a disease. We hypothesized that metabolomic would be helpful in assessing a specific pattern in heart failure patients, also according to the underlining causes and in defining, prior to device implantation, the responder and nonresponder patient to cardiac resynchronization therapy (CRT). METHODS: In this prospective study, blood and urine samples were collected from 32 heart failure patients who underwent CRT. Clinical, electrocardiography and echocardiographic evaluation was performed in each patient before CRT and after 6 months of follow-up. Thirty-nine age and sex-matched healthy individuals were chosen as control group. For each sample, 1H-NMR spectra, Nuclear Overhauser Enhancement Spectroscopy, Carr-Purcell-Meiboom-Gill and diffusion edited spectra were measured. RESULTS: A different metabolomic fingerprint was demonstrated in heart failure patients compared to healthy controls with high accuracy level. Metabolomics fingerprint was similar between patients with ischemic and nonischemic dilated cardiomyopathy. At 6-month follow-up, metabolomic fingerprint was different from baseline. At follow-up, heart failure patients' metabolomic fingerprint remained significantly different from that of healthy controls, and accuracy of cause discrimination remained low. Responders and nonresponders had a similar metabolic fingerprint at baseline and after 6 months of CRT. CONCLUSION: It is possible to identify a metabolomic fingerprint characterizing heart failure patients candidate to CRT, it is independent of the different causes of the disease and it is not predictive of the response to CRT.