Contractibility sensor signal evolution predicts cardiovascular events in patients with cardiac resynchronization therapy.

BACKGROUND: While a multicentre trial has demonstrated that the SonR™ contractibility sensor is as effective as echocardiography-guided optimization at improving response to cardiac resynchronization therapy, an association between SonR™ values and clinical endpoints has not been established.

AIMS: The primary objective was to assess the predictive value of SonR™ signal evolution regarding cardiovascular events in patients implanted with a cardiac resynchronization therapy device. The secondary objective was to evaluate whether SonR™ signal evolution was associated with cardiovascular death.

METHODS: All patients with a SonR™ system implanted between 2012 and 2016 were included in this retrospective study. SonR™ signal evolution was calculated over the first 6 months after implantation: ([month 6 value-month 1 value]/month 1 value)*100. The primary endpoint (cardiovascular events) was a composite of cardiovascular death, hospitalization for acute heart failure or ventricular arrhythmia.

RESULTS: Seventy-four patients (median age 67 years; 81% men) were followed up over a median 20 (13; 29) months. Cumulative incidence function showed that SonR™ signal evolution was predictive of cardiovascular events (threshold<10.70%; P=0.023) and predictive of cardiovascular death (P=0.0018). After multivariable analysis, SonR™ signal evolution was independently associated with the onset of cardiovascular events (hazard ratio: 4.03, 95% confidence interval: 1.31-12.43; P=0.015), even after adjustment for left bundle branch block and chronic kidney disease.

CONCLUSIONS: In this first study publishing data on SonR™ signals in a real-life setting, SonR™ signal evolution over the first 6 months after cardiac resynchronization implantation was an independent predictor of cardiovascular events at follow-up. This variable could be useful to identify patients at higher risk of further adverse events after cardiac resynchronization implantation.