The effect of propofol on frontal QRS-T angle in patients undergoing elective colonoscopy procedure.

WHAT IS KNOWN AND OBJECTIVE: Propofol is a most commonly used anaesthetic drug for conscious sedation in outpatient procedures. Previous studies have shown that propofol may affect ventricular repolarization based on QT and Tp-e intervals. Frontal QRS-T angle is a marker of ventricular depolarization and repolarization difference. However, there is no study investigating the effect of propofol on frontal QRS-T angle. In this study, we aimed to investigate the effect of propofol on frontal QRS-T angle in patients undergoing colonoscopy procedure. METHOD: A total of 56 patients (53.5% females) who underwent colonoscopy procedure were included in this study. All patients underwent 12-lead surface electrocardiograms (ECGs) just before colonoscopy and 15 minutes after colonoscopy. QT interval, QTc interval, Tp-e interval, Tp-e/QT, Tp-e/QTc and frontal QRS-T angle were calculated from 12-lead ECGs. RESULTS AND DISCUSSION: The frontal QRS-T angle was significantly increased 15 minutes after colonoscopy compared to basal value (36.2 ± 24.3 vs. 29.5 ± 23.6, P = .003). In addition, repolarization parameters including QT, QTc and Tp-e intervals were significantly prolonged at 15 minutes after colonoscopy compared to basal value, except Tp-e/QT and Tp-e/QTc. Significant ventricular or supraventricular arrhythmias were not observed in any patient during the procedure. WHAT IS NEW AND CONCLUSION: In this study, we found that propofol administration increased the frontal QRS-T angle in patients undergoing colonoscopy procedure. Given that a prolonged frontal QRS-T angle is associated with ventricular arrhythmias, it may be safer to monitor those patients receiving propofol during colonoscopy procedures.

Mean platelet volume is not associated with coronary slow flow: a retrospective cohort study.

OBJECTIVE: To investigate mean platelet volume (MPV) levels in patients with coronary slow flow (CSF). METHODS: 465 stable angina pectoris cases with angiographically normal coronary arteries were recruited [coronary slow flow group (n=76), control group (n=389)] in the observational retrospective cohort study. Clinical, biochemical and demographic variables including MPV were noted and coronary blood flow was assessed with TIMI frame count (TFC). RESULTS: Gender, smoking, height, serum creatinine, uric acid levels, hemoglobin, waist/hip ratio, systolic blood pressure but not MPV were significantly different among groups. Independent predictors of CSF were height (p=.029) and serum uric acid level (p=.045). Gender, height, weight, hip circumference, systolic blood pressure, fasting blood glucose, serum urea, creatinine, uric acid levels, hemoglobin and platelet count were associated with mean TFC whereas independent predictors of mean TIMI frame count were height (p=.010) and serum uric acid level (p=.041). CONCLUSION: Height and serum uric acid level but not MPV were independent predictors of both CSF and mean TFC.