Cardiac resynchronization therapy by multipoint pacing improves response of left ventricular mechanics and fluid dynamics: a three-dimensional and particle image velocimetry echo study

Europace. 2017 Nov 1;19(11):1833-1840. doi: 10.1093/europace/euw331.

Abstract

Aims: To characterize the effect of multipoint pacing (MPP) compared to biventricular pacing (BiV) on left ventricle (LV) mechanics and intraventricular fluid dynamics by three-dimensional echocardiography (3DE) and echocardiographic particle imaging velocimetry (Echo-PIV).

Methods and results: In 11 consecutive patients [8 men; median age 65 years (57-75)] receiving cardiac resynchronization therapy (CRT) with a quadripolar LV lead (Quartet,St.Jude Medical,Inc.), 3DE and Echo-PIV data were collected for each pacing configuration (CRT-OFF, BiV, and MPP) at follow-up after 6 months. 3DE data included LV volumes, LV ejection fraction (LVEF), strain, and systolic dyssynchrony index (SDI). Echo-PIV was used to evaluate the directional distribution of global blood flow momentum, ranging from zero, when flow force is predominantly along the base-apex direction, up to 90° when it becomes transversal. MPP resulted in significant reduction in end-diastolic and end-systolic volumes compared with both CRT-OFF (P = 0.02; P = 0.008, respectively) and BiV (P = 0.04; P = 0.03, respectively). LVEF and cardiac output were significant superior in MPP compared with CRT-OFF, but similar between MPP and BiV. Statistical significant differences when comparing global longitudinal and circumferential strain and SDI with MPP vs. CRT-OFF were observed (P = 0.008; P = 0.008; P = 0.01, respectively). There was also a trend towards improvement in strain between BiV and MPP that did not reach statistical significance. MPP reflected into a significant reduction of the deviation of global blood flow momentum compared with both CRT-OFF and BiV (P = 0.002) indicating a systematic increase of longitudinal alignment from the base-apex orientation of the haemodynamic forces.

Conclusion: These preliminary results suggest that MPP resulted in significant improvement of LV mechanics and fluid dynamics compared with BiV. However, larger studies are needed to confirm this hypothesis.

Keywords: 3D echocardiography; Cardiac fluid mechanics; Cardiac resynchronization therapy; Heart failure; Multipoint pacing; Particle image velocimetry.

Publication types

  • Comparative Study

MeSH terms

  • Aged
  • Biomechanical Phenomena
  • Cardiac Resynchronization Therapy / adverse effects
  • Cardiac Resynchronization Therapy / methods*
  • Cardiac Resynchronization Therapy Devices
  • Echocardiography, Doppler, Pulsed*
  • Echocardiography, Three-Dimensional*
  • Female
  • Heart Failure / diagnostic imaging
  • Heart Failure / physiopathology
  • Heart Failure / therapy*
  • Humans
  • Hydrodynamics
  • Image Interpretation, Computer-Assisted
  • Male
  • Middle Aged
  • Models, Cardiovascular*
  • Myocardial Contraction*
  • Patient-Specific Modeling*
  • Predictive Value of Tests
  • Preliminary Data
  • Stroke Volume
  • Time Factors
  • Treatment Outcome
  • Ventricular Dysfunction, Left / diagnostic imaging
  • Ventricular Dysfunction, Left / physiopathology
  • Ventricular Dysfunction, Left / therapy*
  • Ventricular Function, Left*