Refining success of cardiac resynchronization therapy using a simple score predicting the amount of reverse ventricular remodelling: results from the Markers and Response to CRT (MARC) study

Aims: Cardiac resynchronization therapy (CRT) reduces morbidity and mortality in systolic heart failure patients with ventricular conduction delay. Variability of individual response to CRT warrants improved patient selection. The Markers and Response to CRT (MARC) study was designed to investigate markers related to response to CRT. Methods and results: We prospectively studied the ability of 11 clinical, 11 electrocardiographic, 4 echocardiographic, and 16 blood biomarkers to predict CRT response in 240 patients. Response was measured by the reduction of indexed left ventricular end-systolic volume (LVESVi) at 6 months follow-up. Biomarkers were related to LVESVi change using log-linear regression on continuous scale. Covariates that were significant univariately were included in a multivariable model. The final model was utilized to compose a response score. Age was 67 +/- 10 years, 63% were male, 46% had ischaemic aetiology, LV ejection fraction was 26 +/- 8%, LVESVi was 75 +/- 31 mL/m2, and QRS was 178 +/- 23 ms. At 6 months LVESVi was reduced to 58 +/- 31 mL/m2 (relative reduction of 22 +/- 24%), 130 patients (61%) showed >/= 15% LVESVi reduction. In univariate analysis 17 parameters were significantly associated with LVESVi change. In the final model age, QRSAREA (using vectorcardiography) and two echocardiographic markers (interventricular mechanical delay and apical rocking) remained significantly associated with the amount of reverse ventricular remodelling. This CAVIAR (CRT-Age-Vectorcardiographic QRSAREA -Interventricular Mechanical delay-Apical Rocking) response score also predicted clinical outcome assessed by heart failure hospitalizations and all-cause mortality. Conclusions: The CAVIAR response score predicts the amount of reverse remodelling after CRT and may be used to improve patient selection. Clinical Trials: NCT01519908

Temporal patterns and short-term progression of paroxysmal atrial fibrillation: data from RACE V

Aims: Atrial fibrillation (AF) often starts as a paroxysmal self-terminating arrhythmia. Limited information is available on AF patterns and episode duration of paroxysmal AF. In paroxysmal AF patients, we longitudinally studied the temporal AF patterns, the association with clinical characteristics, and prevalence of AF progression. Methods and results: In this interim analysis of the Reappraisal of AF: Interaction Between HyperCoagulability, Electrical Remodelling, and Vascular Destabilisation in the Progression of AF (RACE V) registry, 202 patients with paroxysmal AF were followed with continuous rhythm monitoring (implantable loop recorder or pacemaker) for 6 months. Mean age was 64 ± 9 years, 42% were women. Atrial fibrillation history was 2.1 (0.5–4.4) years, CHA2DS2-VASc 1.9 ± 1.3, 101 (50%) had hypertension, 69 (34%) heart failure. One-third had no AF during follow-up. Patients with long episodes (>12 hours) were often men with more comorbidities (heart failure, coronary artery disease, higher left ventricular mass). Patients with higher AF burden (>2.5%) were older with more comorbidities (worse renal function, higher calcium score, thicker intima media thickness). In 179 (89%) patients, 1-year rhythm follow-up was available. On a quarterly basis, average daily AF burden increased from 3.2% to 3.8%, 5.2%, and 6.1%. Compared to the first 6 months, 111 (62%) patients remained stable during the second 6 months, 39 (22%) showed progression to longer AF episodes, 8 (3%) developed persistent AF, and 29 (16%) patients showed AF regression. Conclusions: In paroxysmal AF, temporal patterns differ suggesting that paroxysmal AF is not one entity. Atrial fibrillation burden is low and determined by number of comorbidities. Atrial fibrillation progression occurred in a substantial number. Trial registration number: Clinicaltrials.gov identifier NCT02726698