K. Vernooy

Adenosine testing after second-generation balloon devices (cryothermal and laser) mediated pulmonary vein ablation for atrial fibrillation

AimsAdenosine administration after pulmonary vein (PV) isolation using radiofrequency and cryoablation can cause acute recovery of conduction to the PVs and predicts atrial fibrillation (AF) recurrence. This study evaluated whether adenosine testing after second-generation balloon devices (cryothermal and laser) could reveal dormant PV reconduction and recurrence rate of AF.MethodsOut of total 60 patients, 20 patients underwent PV isolation using laser balloon and for the remaining patients, the cryoballoon was used. Following PVI, waiting period of 30xa0min was obtained. Thereafter, a bolus 15–21xa0mg of adenosine was injected followed by rapid saline flush. The subsequent response was assessed for each vein using an in situ lasso catheter. Further ablation (if needed) using laser balloon and cryocatheter respectively was done, until no reconduction occurred after repeat adenosine.ResultsAcute PV isolation was achieved in all 80 PVs of 20 patients (100xa0%) using laser device and in 151 PVs (96.2xa0%) of 38 patients (95xa0%) using cryoballoon. However, in seven patients (35xa0%), 11 PVs (13.7xa0%) (4 LSPV, 2 LIPV, 4 RSPV, and 1 RIPV) showed dormant PV potentials after adenosine administration in laser group. Cryoballoon group showed dormant reconduction in four patients (10xa0%), four PVs (5xa0%) [one LSPV, one LIPV, and two RIPV]. The follow-up of 337u2009±u200992.4xa0days for cryoballoon and 267u2009±u200976.9xa0days for laser balloon group demonstrated similar success rates (85xa0%).ConclusionAdenosine testing after PV isolation using second-generation balloon based energy devices (laser and cryothermal) reveals dormant conduction in initially isolated PVs with similar long-term success rate.

Different regions of latest electrical activation during left bundle-branch block and right ventricular pacing in cardiac resynchronization therapy patients determined by coronary venous electro-anatomic mapping

Current targeted left ventricular (LV) lead placement strategy is directed at the latest activated region during intrinsic activation. However, cardiac resynchronization therapy (CRT) is most commonly applied by simultaneous LV and right ventricular (RV) pacing without contribution from intrinsic conduction. Therefore, targeting the LV lead to the latest activated region during RV pacing might be more appropriate. We investigated the difference in LV electrical activation sequence between left bundle‐branch block (LBBB) and RV apex (RVA) pacing using coronary venous electro‐anatomic mapping (EAM).

Comparison of strain parameters in dyssynchronous heart failure between speckle tracking echocardiography vendor systems

BackgroundAlthough mechanical dyssynchrony parameters derived by speckle tracking echocardiography (STE) may predict response to cardiac resynchronization therapy (CRT), comparability of parameters derived with different STE vendors is unknown.MethodsIn the MARC study, echocardiographic images of heart failure patients obtained before CRT implantation were prospectively analysed with vendor specific STE software (GE EchoPac and Philips QLAB) and vendor-independent software (TomTec 2DCPA). Response was defined as change in left ventricular (LV) end-systolic volume between examination before and six-months after CRT implantation. Basic longitudinal strain and mechanical dyssynchrony parameters (septal to lateral wall delay (SL-delay), septal systolic rebound stretch (SRSsept), and systolic stretch index (SSI)) were obtained from either separate septal and lateral walls, or total LV apical four chamber. Septal strain patterns were categorized in three types. The coefficient of variation and intra-class correlation coefficient (ICC) were analysed. Dyssynchrony parameters were associated with CRT response using univariate regression analysis and C-statistics.ResultsTwo-hundred eleven patients were analysed. GE-cohort (nxa0=xa0123): age 68xa0years (interquartile range (IQR): 61–73), 67% male, QRS-duration 177xa0ms (IQR: 160–192), LV ejection fraction: 26xa0±xa07%. Philips-cohort (nxa0=xa088): age 67xa0years (IQR: 59–74), 60% male, QRS-duration: 179xa0ms (IQR: 166–193), LV ejection fraction: 27xa0±xa08. LV derived peak strain was comparable in the GE- (GE: -7.3xa0±xa03.1%, TomTec: −6.4xa0±xa02.8%, ICC: 0.723) and Philips-cohort (Philips: −7.7xa0±xa02.7%, TomTec: −7.7xa0±xa03.3%, ICC: 0.749). SL-delay showed low ICC values (GE vs. TomTec: 0.078 and Philips vs. TomTec: 0.025). ICC’s of SRSsept and SSI were higher but only weak (GE vs. TomTec: SRSsept: 0.470, SSI: 0.467) (Philips vs. QLAB: SRSsept: 0.419, SSI: 0.421). Comparability of septal strain patterns was low (Cohen’s kappa, GE vs. TomTec: 0.221 and Philips vs. TomTec: 0.279). Septal strain patterns, SRSsept and SSI were associated with changes in LV end-systolic volume for all vendors. SRSsept and SSI had relative varying C-statistic values (range: 0.530–0.705) and different cut-off values between vendors.ConclusionsAlthough global longitudinal strain analysis showed fair comparability, assessment of dyssynchrony parameters was vendor specific and not applicable outside the context of the implemented platform. While the standardization taskforce took an important step for global peak strain, further standardization of STE is still warranted.