Electrocardiographic (ECG) strain has been linked to excess cardiovascular morbidity and mortality in asymptomatic patients with aortic stenosis. We aim to determine the differential impact of baseline ECG-strain on long-term mortality after transcatheter aortic valve implantation (TAVI). Patients who underwent TAVI from January 2012 to March 2016 at Mayo Clinic were included. Left ventricular (LV) strain was defined as the presence of ≥1mm convex ST-segment depression with asymmetrical T-wave inversion in leads V5 to V6 on baseline ECG. Primary end point was all-cause long-term mortality. Of the 520 patients screened, 130 were excluded due to left bundle branch block or paced rhythm. Median follow-up was 1.5 years, IQR (0.9 to 2.7). In the 390 included patients, 47 (12%) had strain pattern on pre-TAVI ECG. Patients in the strain group had higher prevalence of peripheral vascular disease (83% vs 68%, p = 0.04), and atrial fibrillation/flutter (51% vs 37%, p = 0.06). They also had lower mean LV-ejection fraction (51 ± 16% vs 58±12%, p = 0.003, larger LV-internal diameter in systole (3.71 ± 1.04 cm vs 3.26 ± 0.75 cm), higher LV-mass-index (136 ± 44 vs 121 ± 29 g/m2; p = 0.044), and higher estimated pulmonary artery systolic pressure (50 ± 13 vs 43 ± 15 mm Hg; p = 0.02). Kaplan-Meier survival analysis showed a cumulative probability of survival at 3 years of 35.4% ± 8% in patients with LV-strain compared with 67% ± 3.4% in patients without LV-strain (log-rank p <0.001). In a multivariate logistic regression analysis, ECG-strain was an independent predictor of long-term mortality (Hazard ratio 2.67, 95% CI [1.72 to 4.05]; p <0.001). In conclusion, ECG strain is an independent predictor of long-term mortality post TAVI. Systematic strain measurements might aid in risk-stratifying patients who underwent TAVI.
ASJC Scopus subject areas
- Cardiology and Cardiovascular Medicine