Search

Background: Based on a reduction in morbidity and mortality, cardiac resynchronisation therapy (CRT) has evolved as a standard therapy for patients with advanced heart failure., Objective: To provide insight into patient demographics, safety, echocardiographic remodelling and long-term follow-up of patients treated with CRT in a "real-world" setting at a Swiss tertiary care centre., Methods: Patients implanted with a CRT device at the University Heart Centre Zurich between 2000 and 2015 were consecutively enrolled. Initial clinical and echocardiographic therapy response as well as long-term follow-up for mortality (defined as all-cause death, heart transplantation or ventricular assist device implantation) and hospitalisation for heart failure were assessed., Results: A total of 418 patients with a median age of 66 years at the time of CRT implantation (78% male) were enrolled. Serious peri-interventional complications (from the time of implantation up to 14 days thereafter) were rare and included systemic infections in 2.4%, pneumothorax in 3.3% and haematoma requiring revision in 2.2% of cases. Overall, the Kaplan-Meier estimate for 5-year freedom from the composite endpoint (hospitalisation for heart failure or mortality) was 55.8%; the Kaplan-Meier estimate for 5-year freedom from mortality was 64.1%. CRT was associated with a significant symptomatic improvement and left ventricular reverse remodelling. Overall, 3.9% of patients did not respond to cardiac resynchronisation therapy (decline in left ventricular ejection fraction [LVEF] >5%), whereas 35.1% experienced neither a continued decline nor a relevant improvement of LVEF (±5%). In the remaining 61% of patients we observed an improvement in LVEF of more than 5%. Forty percent and 31% of patients were super responders, defined as an absolute LVEF improvement of 10% and by a relative reduction of left ventricular end-diastolic volume index by 20% or more. Super-response to CRT was associated with a significant benefit in terms of survival and rehospitalisation rates., Conclusion: Our data are consistent with large multicentre trials and indicate that CRT is similarly effective in a real-world setting in Switzerland.

Background: Cardiac resynchronization therapy (CRT) reduces morbidity and mortality in patients suffering from chronic heart failure (CHF). Optimal device programming is crucial for maximum patient benefit. The goal of the present study was to assess device settings from CHF patients undergoing CRT optimization in a "real world" setting, and to delineate parameters most frequently requiring adjustment., Methods: All patients who underwent CRT device implantation in the Cardiology Clinicat the University Hospital Zurich between January 2011 and September 2012 and in whom follow-up was available were included in this analysis., Results: A total of 170 CHF patients were included in this analysis. True biventricular pacing was present in 44% of all patients, while QRS fusion was detected in 49.9%. The majority of the patients presented with suboptimal atrioventricular (AV) delays requiring adjustment. AV delays were therefore shortened due to the presence of QRS fusion in 53.3% and 38.1% of patients (sAV and pAV, respectively) or prolonged because of truncation of the A wave in the left ventricular inflow pulse wave Doppler measurement (17.5% and 28.4% for sAV and pAV, respectively). In contrast, interventricular delay (VV delay) was rarely changed (11.9%)., Conclusions: In our "real world" cohort, a substantial proportion of patients presented to their first post-operative consultation with suboptimal device settings. Our data indicate that the opportunity to optimize device settings is frequently wasted in the "real world", underlining the necessity for expert device follow-up to deliver optimal care to this challenging group of heart failure patients.

Background: The individual benefit from cardiac resynchronisation therapy (CRT) varies largely among patients., Aims: To compare different definitions of echocardiographic super-response to CRT regarding their ability to predict the incidence of adverse events., Methods: Three definitions of super-response to CRT were evaluated in 110 consecutive patients with CRT implantation: (1) an absolute increase in ejection fraction of ≥ 10%; (2) a decrease in left ventricular end-systolic volume of ≥ 30%; and (3) a decrease in left ventricular end-diastolic volume of ≥ 20%. The primary endpoint was a combination of time to death, heart transplantation, ventricular assist device implantation and hospitalisation for heart failure. Secondary endpoints included time to first appropriate implantable cardioverter defibrillator (ICD) discharge during follow-up., Results: All three definitions of super-response were highly predictive of a reduced risk for reaching the primary combined endpoint (3-year estimators: 64% ± 7% vs 82% ± 7% for ejection fraction ≥ 10%; 63% ± 8% vs 92% ± 5% for end-systolic volume ≥ 30%; and 62% ± 8% vs 94% ± 4% for end-diastolic volume ≥ 20%; all p<0.001). In all three analyses, super-responders had a significantly shorter time from diagnosis of heart failure until the time point of CRT implantation. However, even super-responders, independent of the definition, did experience appropriate ICD discharges during follow-up., Conclusions: All three definitions of super-response are highly predictive for a favourable outcome after CRT. However, even patients with pronounced reverse left ventricular remodelling experience appropriate ICD discharges during follow-up.

Background: For successful cardiac resynchronisation therapy (CRT) a spatial and electrical separation of right and left ventricular electrodes is essential. The spatial distribution of electrical delays within the coronary sinus (CS) tributaries has not yet been identified., Objective: Electrical delays within the CS are described during sinus rhythm (SR) and right ventricular pacing (RVP). A coordinate system grading the mitral ring from 0° to 360° and three vertical segments is proposed to define the lead positions irrespective of individual CS branch orientation., Methods: In 13 patients undergoing implantation of a CRT device 6±2.5, (median 5) lead positions within the CS were mapped during SR and RVP. The delay to the onset and the peak of the local signal was measured from the earliest QRS activation or the pacing spike. Fluoroscopic positions were compared to localizations on a nonfluoroscopic electrode imaging system., Results: During SR, electrical delays in the CS were inhomogenous in patients with or without left bundle branch block (LBBB). During RVP, the delays increased by 44±32 ms (signal onset from 36±33 ms to 95±30 ms; p<0.001, signal peak from 105±44 ms to 156±30 ms; p<0.001). The activation pattern during RVP was homogeneous and predictable by taking the grading on the CS ring into account: (% QRS) = 78-0.002 (grade-162)(2), p<0.0001. This indicates that 78% of the QRS duration can be expected as a maximum peak delay at 162° on the CS ring., Conclusion: Electrical delays within the CS vary during SR, but prolong and become predictable during RVP. A coordinate system helps predicting the local delays and facilitates interindividual comparison of lead positions irrespective of CS branch anatomy.