Frontal plane QRS-T angle may be a predictor for post-coronary artery bypass graft surgery atrial fibrillation

Frontal QRS-T angle may predict reverse dipping pattern in masked hypertensives

AIMS

The frontal QRS-T (fQRST) angle is associated with worse cardiovascular outcome. The study aimed to assess the effect of reverse dipping pattern on f(QRST) angle in newly diagnosed masked hypertensive (MH) patients.

MATERIALS AND METHODS

Newly diagnosed 244 consecutive MH patients were included. According to dipping pattern, patients were grouped into three: dipper (n = 114), non-dipper (n = 106), and reverse dipper (n = 24) patterns. The f(QRST) angle, QT and corrected QT interval, and QT dispersion were measured from the 12-lead surface electrocardiogram and compared between groups.

RESULTS

Of all, 51.2% (n = 125) were male. No gender difference was observed. Reverse dipper MH group had a significantly higher f(QRST) angle than the non-dipper and dipper MH groups (77.9 ± 8.6 vs. 32.4 ± 18.8 and 26.0 ± 18.5, respectively, p < .001). The cutoff value for f(QRST) angle of 51 predicts reverse dipping pattern (AUC: 0.84; 95% CI: 0.77-0.90; p < .001), with a sensitivity of 83% and a specificity of 78%.

CONCLUSION

This study revealed that f(QRST) angle is gradually increased starting from the dipper, non-dipper to reverse dipper masked hypertensives. The f(QRST) angle appears as an easy marker for the detection and risk stratification of hypertensive patients.

Frontal plane QRS-T angle predicts early recurrence of acute atrial fibrillation after successful pharmacological cardioversion with intravenous amiodarone

WHAT IS KNOWN AND OBJECTIVE

Although restoration of sinus rhythm is the integral part of the atrial fibrillation (Af) management, recurrence frequency of Af is high after cardioversion. However, little is known about the association of electrocardiography (ECG) parameters with Af recurrence after restoration of sinus rhythm. The present study aimed to investigate whether frontal plane QRS-T (fQRST) angle, as a marker of ventricular repolarization heterogeneity, predicts Af recurrence after successful pharmacological cardioversion.

METHODS

One hundred and sixty-five paroxysmal Af patients with an acute Af episode who underwent successful pharmacological cardioversion with intravenous amiodarone infusion were included into the study. Patients were divided into two groups according to presence or absence of in-hospital Af recurrence. The association between fQRST angle and Af recurrence was investigated.

RESULTS AND DISCUSSION

Af recurrence was observed in 42 (25.4%) patients. The mean fQRST angle was significantly higher in patients with Af recurrence compared to those without Af recurrence (90 ± 45.8 vs. 51 ± 38.2, p < 0.001). Also, Af recurrence was more frequent in patients who had fQRST angle >90˚, compared to patients with fQRST angle ≤90˚ (54.1% vs. 13.7%, p < 0.001). Moreover, ROC curve analysis demonstrated that an increased fQRST angle >92.5˚ predicted in-hospital Af recurrence with a sensitivity of 76.2% and a specificity of 81.4% (AUC:0.728, p < 0.001). Furthermore, multivariate analysis demonstrated that fQRST angle was an independent predictor of in-hospital Af recurrence after successful pharmacological cardioversion (OR: 1.892, 95% CI: 1.361-2.917, p < 0.001).

WHAT IS NEW AND CONCLUSION

As a parameter that can be easily calculated from automated ECG recordings, fQRST angle may be useful in the prediction of early Af recurrence after successful pharmacological cardioversion with amiodarone.