Effects of acute carbon monoxide poisoning on the P-wave and QT interval dispersions.

Objective: The aim of our study was to investigate atrial conduction and ventricular repolarization inhomogeneities using P-wave dispersion (Pwd) and QT dispersion (QTd) analyses in acute carbon monoxide (CO) poisoning.

Methods: Sixty patients were retrospectively included in this case-controlled study. Thirty acute CO poisoning patients were assigned to the Group with acute CO poisoning (ACOP). Patients who did not have acute CO poisoning were assigned to the control group (Group C, n=30). Anthropometric measurement, body mass index, electrocardiogram (ECG) and serum electrolyte levels were recorded in all patients. Also, carboxyhemoglobin (COHb) levels were recorded in Group ACOP. Pwd, QT interval and QTd durations were measured. Corrected QT (QTc) and QTc dispersion (QTcd) intervals were determined with the Bazett formula. Independent samples t and Chi-square tests were used for statistical analysis.

Results: No statistically significant difference was found between the age, gender distribution, anthropometric measurement, serum electrolytes, PR and QT durations between the groups. The Pwd (56.33 ± 17.11 msec vs 28.33 ± 11.16 msec, p=0.001) and QTd (63.33 ± 26.69 msec vs 42.16 ± 7.84 msec, p=0.001) were significantly longer in Group ACOP than in Group C. In addition, QTc and QTcd durations of Group ACOP were also found to be significantly longer than in Group C (p=0.001).

Conclusion: In our study, we found in ECG analyses of patients with acute CO poisoning that the Pwd, QTc and QTcd durations were significantly prolonged when compared with control group. For this reason, patients with acute CO poisoning need close attention because of arrhythmias, which can be related to increased QTcd and Pwd durations.