Efficacy of catheter ablation of frequent asymptomatic idiopathic PVCs in treating latent left ventricular systolic dysfunction as being assessed by speckle tracking of LV global longitudinal strain

Abstract

Abstract Background Throughout the past decade there were no straightforward recommendations regarding management of asymptomatic PVCs in structurally normal heart. The recent ESC guidelines for management of ventricular arrhythmias and prevention of sudden cardiac death published in 2022 declared overtly that there is a gap of evidence regarding management of asymptomatic high burden PVCs in structurally normal heart. Fear of progression to cardiomyopathy along with high success rates with catheter ablation (CA) brought to our insight the idea of applying the other comprehensive imaging modalities rather than conventional 2D echocardiography to guide the treatment decision. Primary objective was to evaluate the impact of CA of asymptomatic frequent idiopathic PVCs in treatment of early subtle myocardial dysfunction in patients with normal left ventricle ejection fraction (LVEF) and internal dimensions guided by two-dimensional (2D) speckle tracking echocardiography (STE) of global longitudinal strain (GLS) before progression into overt LV systolic dysfunction. Secondary objectives were to assess the correlation between PVCs burden and the degree of impairment of GLS and to assess the correlation between CA of asymptomatic frequent idiopathic PVCs and improvement of patient functional capacity as an indicator for subconscious adaptation. Patients and Methods A pilot randomized control trial that included forty asymptomatic patients with high burden ≥ 20% of idiopathic PVCs with normal LVEF and normal LV structure as being assessed by conventional 2D echocardiography, and impaired LV GLS by 2D STE. Those patients were furtherly randomized into two groups each contained twenty patients, group A (control group): subjected to the standard of care which is regular follow up of symptom status and LVEF, and group B (ablation group): scheduled for CA. Results Our results showed a negative correlation between baseline PVCs burden and baseline LV GLS with r value -0.490 ,P value 0.001. Moreover, there was a negative correlation between PVCs QRS width and baseline LV GLS with r value -0.371 and P value 0.018. There was a significant improvement in LV GLS in group B post intervention, with baseline LV GLS in group B ranging from -12.4% to -15.7% and mean value of -14.71 ± 0.81% rising post ablation to a range of -15.8% to -20% with mean value of -17.93 ± 1.06 %, P value <0.001. There was a significant reduction in LV GLS in group A with follow up, baseline LV GLS in group A ranged from -12.6% to -15.6% with mean value of -14.4 ± 0.74 % while it ranged from -11.7% to -15.3% at follow up with mean value of -13.85 ± 0.92%. Conclusion LV GLS assessment as an early marker of latent LV systolic dysfunction can serve as a potential guidance tool for allocating patients with normal LVEF and frequent idiopathic PVCs to an ablation strategy. CA of PVCs is an effective treatment strategy to reverse latent systolic dysfunction before progression to overt dysfunction.Work flow of study population graphic abstract of the study