P-wave duration and dispersion in patients with coronary slow flow and its relationship with Thrombolysis in...

P-wave dispersion (PD), and duration has been reported to be associated with inhomogeneous and discontinuous propagation of sinus impulses. The aim of this study was to investigate the PD in patients with coronary slow flow (CSF) phenomenon.

Study population included 48 patients with angiographically proven normal coronary arteries and slow coronary flow in all 3 coronary vessels (group I, 36 men; mean age, 54 +/- 9 years) and 32 subjects with angiographically proven normal coronary arteries without associated slow coronary flow (group II, 24 men, mean age, 53 +/- 10 years). Coronary flow rates of all patients and control subjects were documented by Thrombolysis In Myocardial Infarction (TIMI) frame count. All patients in group I had TIMI frame counts greater than 2 SD above those of control subjects (group II). The mean TIMI frame count for each patient and control subject was calculated by adding the TIMI frame counts for each major epicardial coronary artery and then dividing the obtained value into 3. The maximum and minimum P-wave duration (P(max) and P(min)) and PD were measured from the 12-lead surface electrocardiogram. Echocardiographic examination was also performed.

There was no statistically significant difference between the 2 groups with respect to age, sex, hypertension, diabetes mellitus, hyperlipidemia, and cigarette smoking (P > .05). P-wave dispersion and P(max) of patients with CSF were found to be significantly higher than those of control subjects (39.4 +/- 17 vs 21.2 +/- 10 milliseconds and 121.6 +/- 17.1 vs 104.3 +/- 10.4 milliseconds, respectively; P < .0001). Moreover, we found a significant positive correlation between both P(max) and PD with mean TIMI frame count (r = 0.836 and r = 0.806, respectively; P < .0001).

P-wave dispersion and P-wave duration both were found to be greater in patients with CSF than in controls.