Predicting Mortality following TAVI Using Electrical Voltage on ECG

Background: Transcatheter aortic valve implantation (TAVI) is an important therapeutic option in elderly patients with aortic stenosis. In this population, coexisting cardiac amyloidosis appears to be common and may affect prognosis. Reduced electrical voltage on ECG is a clinical sign of amyloidosis and may help identify AS patients with amyloid prior to TAVI.

Aim: To examine whether electrical voltage on pre-TAVI ECG predicts mortality post TAVI.

Methods: This retrospective study enrolled 246 patients who underwent TAVI in our institution between the years 2008-2015. Patients with a pacemaker rhythm (n=26) were excluded. Using the Sokolow-Lyon criteria and the summation of all R waves in the ECG performed prior to intervention, we divided the patients into 3 tertiles of voltage and compared mortality after 30- and 365-day periods. In addition, we assessed mortality using voltage as a continuous variable.

Results: For the Sokolow-Lyon criteria groups were divided from lowest to 18mm, 18-26mm and 26mm and higher. Mean age was 80.5, 80.6, and 81.7,years respectively. The percentage of women in the groups was 46, 55, and 51%, respectively. For 30 days, death rate was 5.4%,2.8%,and 4.1% . For 365 days, death rates were 13.6%,12.6% and 10.9%. There were no statistically significant differences in mortality between the groups at any of the time points examined. Results using the summation of total R waves to assess voltage were similar with no significant differences in mortality. Assessing this relation using the sum of total R waves as a continuous variable, revealed no statistically significant difference in mortality within 30 (P-Value=0.75) or 365 days (P-Value=0.53).

Conclusion: Our findings suggest that ECG voltage on ECG does not predict mortality after TAVI. Further study in larger cohorts may be necessary to examine this question.