Patients and clinical characteristics
Detailed patients’ demographic information and clinical characteristics are presented in Table 1 . The average age was 40.7 ± 17.3 years (range 11 to 73 years). Of the 78 study patients, 48 (61.5%) were male. None were taking any antiarrhythmic medications, including amiodarone.
Regarding the 24-h ambulatory Holter ECG, 51 (65.4%) of the 78 study patients had ventricular arrhythmias (VAs), including 51 (65.4%) with PVCs (range 1 to 39,860, median 54), 18 (23.1%) with couplets (range 1 to 4,438, median 39), and 13 (16.7%) with runs of NSVT. The number of NSVT runs in 24 h was from 1 to 3859 (median 2), with 3 to 39 beats in the longest burst (median 8), and with ventricular rates of 148.2 ± 48.6 beats/min. SVT runs were present in one patient. When patients were divided into different groups according to VA morphologies, 43 had monomorphic VAs, and 8 had polymorphic VAs (4 also had polymorphic VT). ST-segment depression was observed in 16 patients (20.5%).
Patients with VAs were older than those without VAs (P=0.023). However, no gender distribution differences were identified between the VAs and non-VAs groups (P=0.763). Moreover, patients with VAs were more likely to have hypertension (P=0.025). There were no significant differences regarding patients age, gender distribution, or other clinical characteristics between the monomorphic and polymorphic VAs group.