Key result
Exercise high-frequency QRS boosts coronary event detection sensitivity to ~63% versus ST-segment analysis, but sacrifices specificity.
Why the study?
Does exercise high-frequency QRS analysis improve diagnostic accuracy for detecting coronary artery disease and short-term adverse cardiac events compared to conventional ST-segment analysis in patients with chest pain and normal baseline ECG?
Cohort (n=337)
No
Does exercise high-frequency QRS analysis improve diagnostic accuracy for detecting coronary artery disease and short-term adverse cardiac events compared to conventional ST-segment analysis in patients with chest pain and normal baseline ECG?
Absolute Event Rate: 63% vs 26%
p-value: p=<0.05
May aid event detection via higher sensitivity in chest pain; leaves open routine use given lower specificity in Level 4 data.
BACKGROUND: The novel analysis of high-frequency QRS components (HFQRS-analysis) has been proposed in patients with chest pain (CP) and normal electrocardiography (ECG) referred for exercise tolerance test (ex-ECG). The aim of the study was to compare the diagnostic value of ex-ECG with ex-HFQRS-analysis. METHODS: Patients with CP and normal ECG, troponin, and echocardiography were considered. All patients underwent ex-ECG for conventional ST-segment-analysis and ex-HFQRS-analysis. A decrease ≥ 50% of the HFQRS signal intensity recorded in at least 2 contiguous leads was considered an index of ischemia, as ST-segment depression ≥ 2 mm or ≥ 1 mm and CP on ex-ECG. Exclusion criteria were: QRS duration ≥ 120 ms and inability to exercise. End-point: The composite of coronary stenosis ≥ 70% or acute coronary syndrome, revascularization, cardiovascular death at 3-month follow-up. RESULTS: Three-hundred thirty-seven patients were enrolled (age 60 ± 15 years). The percent-age of age-adjusted maximal predicted heart rate was 89 ± 10 beat per minute and the maximal systolic blood pressure was 169 ± 23 mm Hg. Nineteen patients achieved the end-point. In multivariate analysis, both ex-ECG and ex-HFQRS were predictors of the end-point. The ex-HFQRS-analysis showed higher sensitivity (63% vs. 26%; p < 0.05), lower specificity (68% vs. 95%; p < 0.001), and comparable negative predictive value (97% vs. 96%; p = 0.502) when compared to ex-ECG-analysis. Receiver operator characteristics analysis showed the incremental diagnostic value of HFQRS (area: 0.655, 95% CI 0.60-0.71) over conventional ex-ECG (0.608, CI 0.55-0.66) and CP score (0.530, CI 0.48-0.59), however without statistical significance in pairwise comparison by C-statistic. CONCLUSIONS: In patients with CP submitted to ex-ECG, the novel ex-HFQRS-analysis shows a valuable incremental diagnostic value over ST-segment-analysis.
No takes yet. Share an insight, caveat, or question.
Conti et al. (2015) conducted a cohort in Chest pain with normal ECG (n=337). Exercise high-frequency QRS (ex-HFQRS) analysis vs. Conventional exercise tolerance test electrocardiography (ex-ECG) ST-segment analysis was evaluated on Sensitivity for the composite of coronary stenosis ≥ 70% or acute coronary syndrome, revascularization, cardiovascular death at 3-month follow-up (p=<0.05). Exercise high-frequency QRS analysis demonstrated higher sensitivity (63% vs. 26%) but lower specificity (68% vs. 95%) than conventional ST-segment analysis for detecting coronary events.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: