QRS fragmentation: its role in sherlocking the arrhythmogenic heart

Electrocardiographic Changes Associated with Early Repolarization Pattern in Healthy Young Males

Background and Objectives: Early repolarization pattern (ERP) has recently been shown to be related with an increased risk of ventricular arrhythmias in susceptible individuals. Materials and Methods: We studied the ERP-associated ECG changes, with potential clinical relevance, in 220 young (age 22.1 ± 1.6 years), healthy, male subjects using 12-lead ECG recordings. A total of 38 subjects (17.3%) fulfilled the diagnostic criteria for ERP, and a total of 90 ECG characteristics were compared between the groups of subjects with and without ERP. Results: None of the ECGs were pathological, and 22 ECG parameters differed significantly (p < 0.05) between the subjects with and without ERP. Among them, the P wave-related parameters (e.g., average P wave duration: 101.5 ± 9.2 ms vs. 106.8 ± 9.9 ms, p = 0.004) and the presence of fragmented QRS complexes (67.6% vs. 92.1%, p = 0.002) revealed a potential propensity for atrial and ventricular arrhythmogenesis. The time-domain parameters of repolarization, those not corrected for QRS duration, showed shorter values (e.g., Tpeak-Tend interval: 70.9 ± 8.1 ms vs. 67.8 ± 8.0 ms, p = 0.036), reflecting the accelerated repolarization. Conclusions: Certain ECG characteristics seem to be more associated with ERP. The clinical significance of this finding at the individual level needs further prospective investigations.

Fragmented QRS as a marker of coronary atherosclerosis severity evaluated by the Gensini score

BACKGROUND

QRS fragmentation (fQRS) represents a marker of local myocardial fibrosis, especially in patients with CAD (coronary artery disease). However, little is known about the association between fQRS and the severity of coronary atherosclerosis as defined by the Gensini score.

OBJECTIVE

To identify the angiographic and echocardiographic characteristics of patients with suspected CAD depending on the location and extent of fQRS.

METHODS

A total of 178 patients who underwent coronary angiography were included in the study. fQRS was defined as the presence of RSR' and/or notching of the R/S wave (if QRS<120ms) or≥2 notches of the R/S wave (if QRS≥120ms). All patients were divided into three groups: non-fQRS; fQRS in 1-2 and≥3 leads.

RESULTS

Statistically significant differences in the LVEF (left ventricular ejection fraction, P=0.009) and the degree of coronary atherosclerosis severity (P=0.008) were found among 3 groups. The median Gensini score was 7 in non-fQRS group (minimal CAD) and >20 in other groups (severe CAD). Both the anterior and lateral fQRS groups had a lower LVEF compared to no fQRS (P=0.039 and P=0.01, respectively). The median Gensini score was significantly higher in case of the lateral fQRS (P=0.037). fQRS in≥1 lead was associated with coronary occlusion (OR 2.1, 95% CI: 1.1-4.1, P=0.038).

CONCLUSIONS

The presence of fQRS, particularly in lateral leads, can be a useful noninvasive marker of severe coronary atherosclerosis. Patients with≥1 fragmented lead have a lower LVEF, a higher Gensini score and a two-fold increased risk of occlusion.

Abnormal ECG Findings in Athletes: Clinical Evaluation and Considerations

PURPOSE OF REVIEW

Pre-participation cardiovascular evaluation with electrocardiography is normal practice for most sporting bodies. Awareness about sudden cardiac death in athletes and recognizing how screening can help identify vulnerable athletes have empowered different sporting disciplines to invest in the wellbeing of their athletes.

RECENT FINDINGS

Discerning physiological electrical alterations due to athletic training from those representing cardiac pathology may be challenging. The mode of investigation of affected athletes is dependent on the electrical anomaly and the disease(s) in question. This review will highlight specific pathological ECG patterns that warrant assessment and surveillance, together with an in-depth review of the recommended algorithm for evaluation.