Efficacy of a Device-Based Continuous Optimization Algorithm for Patients With Cardiac Resynchronization Therapy

Cost-effective analysis of automated programming optimization in cardiac resynchronization therapy: Holistic Markov modelling

BACKGROUND

Automated optimization algorithm (AdaptivCRT; Medtronic, Mounds View, MN, USA) allowing automated optimization of cardiac resynchronization therapy (CRT), has been introduced. However, little is known concerning its cost-effectiveness. This study aims to evaluate the potential economic benefits of AdaptivCRT of CRT.

METHODS

Markov modelling was informed by empirical data sourced from the AdaptivCRT Clinical Trial. Published meta-analyses were used to derive the impact of increasing response to hospitalization and mortality risks. Response was assessed via the clinical composite score.

RESULTS

Deterministic results suggested a mean survival of 10.97 years with adaptive algorithms against 10.5 years without (+0.47 in favour of novel algorithms). Heart failure hospitalization costs were modelled to ¥1,382,753 (US $12,686) with novel devices against ¥1,524,747 (US $13,989) with previous technology models. Sensitivity analyses show CRT with Adaptive algorithm was projected to provide cost savings in all scenarios.

CONCLUSIONS

The use of AdaptivCRT was projected to improve average patient survival and avoid costs in a Japanese healthcare setting.

A new biomarker of cardiac resynchronization therapy response: cGMP to mature BNP ratio

BACKGROUND

Biomarkers that can predict cardiac resynchronization therapy (CRT) response have not yet been identified. The purpose of this study was to assess whether individual measurements of four brain/B-type natriuretic peptide (BNP) forms, coupled with cyclic guanosine monophosphate (cGMP) might contribute to the prediction of echocardiographic CRT responders.

METHODS

A BNP precursor (proBNP) and total BNP (= proBNP + mature BNP) were measured with newly developed kits, while an N-terminal fragment of proBNP (NT-proBNP) and cGMP were measured with commercial kits on the day before CRT implantation. Estimated mature BNP (emBNP = total BNP-proBNP), and the ratio of cGMP to each BNP form, as well as the concentrations of three other BNP forms, were prospectively investigated for their capability in predicting a response to CRT. A CRT responder was defined as an improvement in left ventricular ejection fraction >10% and/or a reduction in left ventricular end-systolic volume >15% at 6-month follow-up.

RESULTS

Out of 77 patients, 46 (60%) were categorized as CRT responders. Among the measurement parameters, only the highest quartile of the cGMP to emBNP ratio was an independent predictor of CRT responders (odds ratio 4.87, 95% confidence interval 1.25-18.89, p = 0.02). The cGMP to emBNP ratio was associated with the cumulative events of heart failure hospitalization within one year following CRT implantation (log-rank p = 0.029).

CONCLUSIONS

The cGMP to emBNP ratio could be utilized as a predictive biomarker of CRT responders. (Clinical Study on Responder Prediction in Cardiac Resynchronization Therapy Using Individual Molecular Measurement of Natriuretic Peptide: UMIN R000038927).

Impact of adaptive cardiac resynchronization therapy in patients with systolic heart failure: Beyond QRS duration and morphology

BACKGROUND

Mechanical and electrical restoration by cardiac resynchronization therapy (CRT) with adaptive pacing algorithm (aCRT) in heart failure patients with a moderately wide (120-149 ms) QRS has not been fully evaluated. The purpose of this study was to investigate the therapeutic effect of aCRT compared with conventional biventricular CRT (BiV-CRT) regardless of QRS morphology.

METHODS

Seventeen consecutive patients with a QRS ≥120 ms, regardless of morphology, underwent CRT device implantation with an aCRT pacing algorithm. Propensity score matched analysis was performed to evaluate the impact of aCRT on the improvement in mechanical and electrical parameters after CRT device implantation using historical controls (HC) from the clinical registry of BiV-CRT (START trial).

RESULTS

Left ventricular (LV) volume significantly decreased after CRT in all patients in both the aCRT and HC groups. The difference in relative reduction of LV end-systolic volume (LVESV) was not significantly different between the 2 arms. QRS shortening after CRT was significantly greater in the aCRT group than in the BiV-CRT group, and the difference was prominent in patients with a moderately wide QRS (120-149 ms). In patients with a moderately wide QRS, the relative reduction in LVESV [39 (29-47)% vs. 2 (-6-20)%, p = 0.04] and proportion of LV volume responders (90% vs. 38%, p = 0.04) were significantly greater in the aCRT group than in the HC group. The proportion of volume responders was not significantly different in patients with a wide QRS (≥150 ms).

CONCLUSIONS

The aCRT algorithm improved electrical and mechanical parameters in patients with a moderately wide QRS, regardless of QRS morphology.