A new arrhythmia entity: sub-inappropriate sinus-node tachycardia
█ Original article
Borbola József, Földesi Csaba, Kardos Attila, Som Zoltán
Gottsegen György Országos Kardiovaszkuláris Intézet, Felnőtt Kardiológiai Osztály, Szívelektrofiziológiai és Pacemaker Terápiás Osztály, Budapest
In the last years, a new patient group (97 patients, 90 women, 7 men; mean age 30.4±9.0 years) was identified with unusual features of inappropriate sinus-node tachycardia. This patient group did not meet the diagnostic criteria of inappropriate sinus node tachycardia (resting sinus-frequency: 86.2±10.1/min; mean daily heart rate on 24 hours Holter-monitoring: 79.9±5.5/min). Otherwise, clinical characteristics were similar to the features of inappropriate sinus-node tachycardia: (1) Predominantly occurring in young women; (2) cardiac or extracardiac causes can be excluded; (3) inappropriate, non-paroxysmal chronotropic response to physical /psychic stress; (4) palpitation is the leading symptom; (5) the quality of life is impaired (EHRA score: 2.3±0.28).
We did not find any reference in the literature regarding this patient group, for distinction the name of sub-inappropriate sinus-node tachycardia was introduced. The treatment is similar to the therapy of inappropriate sinus-node tachycardia: lifestyle change, introducing vagotonic exercises and/or temporal drug treatment. Both the adrenergic beta-receptor blocker bisoprolol (2×5 mg bid, daily) and f-channel blocker ivabradine (2×5 mg bid, daily), decreased significantly the sinus frequency during the 24 hours Holter-ECG monitoring (minimum-maximal-average sinus-frequency/min) (control: 53.7±5.9 – 147.8±14.4 – 82.4±3.9/min, bisoprolol: 49.6±6.1 – 127.9±9.9 – 72.9±7.5 (p<0.01), control: 55.2±2.7 – 148.8±11.7 – 81.3±4.5/min, ivabradine: 52.3±1.2 – 135.0±3.5 (p≤0.01) – 77.5±4.5 (p≤0.05). Not only the sinus-frequency was decreased but also the quality of life parameter, the EHRA score improved (EHRA score: bisoprolol treatment: 0.74±0.52 (p≤0.0001); ivabradine therapy: 0.77±0.43 (p≤0.0001).