Focal atrial tachycardia was complicated by cardiomyopathy in 10% of patients, which was strongly associated with incessant or very frequent paroxysmal tachycardia (100% vs. 20%, p<0.001).
Cohort (n=331)
What are the clinical characteristics of tachycardia-mediated cardiomyopathy secondary to focal atrial tachycardia, and does radiofrequency ablation restore left ventricular function?
Cardiomyopathy complicates 10% of focal atrial tachycardias, particularly slower incessant forms, and left ventricular function is nearly universally restored following successful catheter ablation.
Absolute Event Rate: 100% vs 20%
p-value: p=<0.001
OBJECTIVES: This study aimed to characterize the incidence, clinical and electrophysiologic features, and long-term outcomes of patients with tachycardia-mediated cardiomyopathy (TCM) secondary to focal atrial tachycardia (AT). BACKGROUND: TCM is known to complicate atrial tachyarrhythmias. Little is known of the patient and tachycardia characteristics associated with the development of left ventricular (LV) dysfunction and the long-term outcomes after cure of tachycardia. METHODS: A total of 345 patients with focal AT underwent radiofrequency ablation between January 1997 and July 2008. A retrospective analysis was performed to identify patients with LV dysfunction, defined as an ejection fraction <50% on echocardiography. Patients with pre-existing structural heart disease (n = 14) were excluded. Patients with TCM (n = 30) and without TCM (n = 301) were compared. Recovery of LV function was also assessed. RESULTS: The incidence of TCM was 10%. Incessant or very frequent paroxysmal tachycardia was strongly associated with TCM, compared to patients without TCM (100% vs. 20%, p < 0.001). Patients in the TCM group were younger (mean age 39 +/- 22 years vs. 51 +/- 17 years, p = 0.0006) and more frequently male (60% vs. 38%, p < 0.001). Patients with TCM had a longer mean tachycardia cycle length (502 +/- 131 ms vs. 402 +/- 105 ms, p < 0.0001) and slower ventricular rate (117 +/- 21 beats/min vs. 141 +/- 33 beats/min, p = 0.0007) during tachycardia compared with patients who did not have TCM. Appendage sites are associated with a high incidence of incessant tachycardia (84%) and LV dysfunction (42%). After successful ablation, LV function was restored in 97% of patients at a mean of 3 months. CONCLUSIONS: Cardiomyopathy occurs in 10% of patients with focal AT. A slower incessant tachycardia is more frequently complicated by cardiomyopathy. Long-term restoration of LV function can be achieved after successful catheter ablation of the tachycardia focus.
Medi et al. (Fri,) conducted a cohort in Focal atrial tachycardia (n=331). Tachycardia-mediated cardiomyopathy (TCM) vs. Without TCM was evaluated on Incessant or very frequent paroxysmal tachycardia (p=<0.001). Focal atrial tachycardia was complicated by cardiomyopathy in 10% of patients, which was strongly associated with incessant or very frequent paroxysmal tachycardia (100% vs. 20%, p<0.001).