Real-life use of digoxin in patients with non-valvular atrial fibrillation: data from the RAMSES study.

WHAT IS KNOWN AND OBJECTIVE: Although inappropriate use of digoxin has been described in various populations, a real-world evaluation of patterns of digoxin prescription has not been well studied in patients with atrial fibrillation (AF). The aim of this study was to identify prevalence, indications and appropriateness of digoxin use in the general population of patients with non-valvular AF (NVAF) in Turkey. METHODS: We included and classified patients from the RAMSES (ReAl-life Multicentre Survey Evaluating Stroke prevention strategies in Turkey) study, a prospective registry including 6273 patients with NVAF, on the basis of digoxin use. After excluding the data of 73 patients whose medical history about digoxin use or left ventricle function was absent, 6200 patients were included for the final analysis. Digoxin use was considered inappropriate if patients did not have left ventricular systolic dysfunction or symptomatic heart failure (HF). RESULTS AND DISCUSSION: Digoxin was used in 1274 (20·5%) patients. Patients treated with digoxin were older (71·4 ± 9·8 years vs. 69·2 ± 10·9 years, P < 0·001), more likely to be female (58·8% vs. 55·9%, P = 0·019) and had more common comorbidities such as HF (40·2% vs. 17·4%), diabetes (26·4% vs. 21·1%), coronary artery disease (35·3 vs. 27·6%) and persistent/permanent AF (93·4% vs. 78·4%; P < 0·001 for each comparison). Of the 1274 patients, the indication of digoxin use was considered inappropriate in 762 (59·8%). WHAT IS NEW AND CONCLUSION: Our findings show that nearly one-fifth of the patients with NVAF were on digoxin therapy and nearly 60% of these patients were receiving digoxin with inappropriate indications in a real-world setting.

Evaluation of the acute effect of palonosetron on transmural dispersion of myocardial repolarization.

BACKGROUND: 5-hydroxytryptamine receptor type-3 (5-HT3) antagonists are widely used for prophylaxis of chemotherapy-induced nausea and vomiting (CINV) and regarded to have a high safety profile. However, several electrocardiographic changes and cardiac arrhythmias have been reported due to administration of 5-HT3 antagonists. Only prolongation of QT interval has been investigated as an index of potential for life-threatening arrhythmias in adult patients using 5-HT3 antagonists. Recently, increase in transmural dispersion of repolarization (TDR) has been proposed as a more reliable determinant of arrhythmogenic potential. AIM: To assess the effects of palonosetron, a second-generation 5-HT3 antagonist, on the T-wave peak to T-wave end (TpTe) interval which has been proposed as a reliable index of spatial TDR. PATIENTS AND METHODS: A total of 50 consecutive cancer patients (aged: 57 +/- 12 years) who were scheduled to receive emetogenic chemotherapy were included to the study. Baseline12-lead electrocardiography (ECG) recordings were obtained. Then, all patients received 8 mg intravenous dexamethasone followed by a single dose of 0.25 mg intravenous palonosetron administered over 30 seconds. A second ECG was performed 30 minutes after the administration of palonosetron. Indices of cardiac repolarization and TDR before and after the administration of palonosetron were compared. RESULTS: In comparison with baseline there was no statistically significant change in any of the heart rate-corrected parameters, including QT(c) (lead V5), QT(maxc), QT(minc), QT(cd), TpTe (V5), TpTe(max), TpTe(min), TpTe(d) and TpTe/QT (V5). CONCLUSIONS: Palonosetron does not have any significant effect on QT(c) and TpTe intervals. It might be the drug of choice for prophylaxis of CINV in cancer patients receiving chemotherapy with known cardiotoxic potential or who have pre-existing cardiac disease that predispose them to drug-induced arrhythmias.