Left ventricular torsional parameters before and after atrial fibrillation ablation: a velocity vector imaging study

Abstract

Background and aimEffects of atrial fibrillation (AF) and its ablative treatment on LV torsion have not yet been fully investigated. This study aimed to examine whether AF patterns of LV contraction and its ablative correction can exert a significant impact on LV torsion by velocity vector imaging (VVI).MethodsThis case-control study conducted in Rajaie Cardiovascular, Medical and Research Center between October 2012 and June 2013. Study participants were 30 consecutive patients with symptomatic paroxysmal AF who met the inclusion criteria. The control group included 24 healthy participants with no history of cardiovascular disease. All individuals were in sinus rhythm at the time of echocardiography before and after the ablation procedure. Two-dimensional (2D) and Doppler echocardiography on a commercially available ultrasound system was performed for all the patients. Scanning was done by a wide-band ultrasound transducer with the frequency range between 2.5–3.5 MHz. The two short-axis views at basal and apical levels were subsequently processed off-line by VVI XStrain software. In order for data analysis, SPSS 16 utilized using paired and independent t-test. p-value ≤0.05 was considered significant.ResultsLV torsion (°/cm) mean ± SD was significantly lower in paroxysmal AF patients before ablation (0.8±0.3) than the control group (1.5±0.4) (p<0.001) and increased significantly after ablation (1.1±0.5) compared with before ablation (p=0.004), but still significantly lower than the control group (p=0.003). LV Twist, twist rate and untwist rate mean ± SD were significantly lower in paroxysmal AF patients before ablation than the control group and increased significantly after ablation compared with before ablation, but still significantly lower than the control group.ConclusionSubclinical LV dysfunction may be detected in paroxysmal AF rhythm by measuring torsional parameters through VVI which improves after AF ablation.

Mechanistic insights into atrial functional mitral regurgitation: Far more complicated than just left atrial remodeling

“…18 The fibrous mitral annulus has no intrinsic contractility. 15,21 Additional research will, however, be needed to substantiate this. 18 Hence, the mitral annulus contracts along with the LA in late diastole and together with the LV during systole.…”

“…Evidence supporting this hypothesis comes from data showing that patients with lone AF demonstrate reductions in LV basal circumferential strain and basal twist. 15,21 Additional research will, however, be needed to substantiate this.…”

Variable definitions and treatment approaches for atrial functional mitral regurgitation: A scoping review of the literature

“…Indeed, the structural and hemodynamic changes featuring HFpEF and the electrical instability leading to AF cause isolated mitral annular dilatation, resulting in inadequate leaflets coaptation and regurgitation. Recent reports have pinpointed further structural abnormalities of the LV playing a role in AFMR pathogenesis, such as atriogenic leaflet tethering, 24 reduced mitral annular contractility, 25 and abnormal annulo‐papillary balance due to impaired long‐axis ventricular function 26 . Hamstringing of the posteromedial papillary muscle caused by paradoxical left ventricular posterior wall motion 27 and inadequate leaflet adaptation due to impaired ability to undergo compensatory endothelial‐mesenchymal transformation (EMT) 28 have been shown to play a role as well.…”