Upstream-therapy using telmisartan and amlodipine improves left atrial mechanical function after pulmonary vein antrum isolation

The objective of the study was to estimate the efficacy of telmisartan and amlodipine combination on the restoration of left atrial (LA) mechanical function after atrial fibrillation (AF) radiofrequency catheter ablation.
Methods: 64 consecutive patients undergoing pulmonary vein isolation (PVI) for treatment of paroxysmal atrial fibrillation were included in the study. Patients were randomly assigned to receive either a telmisartan/amlodipine combination 80/5 mg po daily (group I, n=34) or placebo (group II, n=30) for one week post-ablation. Transthoracic echocardiography (TTE) was performed pre-ablation, immediately post-ablation and after one week of study medication therapy. A six-minute walk test was performed and a standard SF-36 questionnaire was administered the day before the procedure and after a week of medication therapy. LV end-diastolic pressure was measured invasively viatransseptal puncture just prior to the PVI at the time of the transeptal puncture and again after the PVI just before LA sheath removal.
Results: Immediately post-ablation in both groups transmitral and pulmonary vein flow demonstrated a ‘pseudo restrictive’ pattern on TTE. The LA ejection fraction and LA active emptying fraction decreased by 25% and 40% respectively (p<0.05). Mean LA pressure, estimated mean pulmonary artery pressure, and right ventricular systolic pressure increased by 60%, 54%, and 44%, respectively (p<0.05). Of note, LV diastolic function did not decline. At the same time, patient-reported quality of life scores and exercise tolerance worsened After one week of therapy with a combination of telmisartan and amlodipine, all hemodynamic parameters, exercise tolerance, and quality of life showed improvement in the therapy group compared to the placebo group.
Conclusion: AF radiofrequency catheter ablation leads to intracardiac hemodynamic deterioration likely by worsening LA elasticity and contractility. This, in turn results in an increase in LA pressure, activation of pulmonary arteriolar spasm reflex, and progression of pulmonary vascular resistance which is seen clinically as a decline in patient exercise tolerance and quality to life. However, the administration of telmisartan and amlodipine pre- and post-ablation appears to improve intracardiac hemodynamics, exercise tolerance and quality of life compared to placebo.