Pacing to Prevent Adverse Left Ventricular Remodeling
What is the effect of peri-infarct pacing on left ventricular (LV) remodeling and clinical outcomes in patients with a large first myocardial infarction (MI)?
In the PRomPT (Post-Myocardial Infarction Remodeling Prevention Therapy) trial, 126 patients at 27 international sites within 10 days of onset of anterior or non-anterior MI with creatine phosphokinase >3000 U/L and QRS duration ≤120 ms were randomized 1:1:1 to dual-site biventricular pacing vs. single-site LV only pacing vs. non-implanted control. The primary endpoint was the echocardiographic core laboratory-assessed change in LV end-diastolic volume (ΔLVEDV) from baseline to 18 months between the pooled pacing therapy groups and the control group. ΔLVEDV from baseline to 18 months between the pooled pacing therapy and control groups was analyzed by analysis of covariance with baseline LVEDV as a covariate.
ΔLVEDV increased by 15.3 ± 28.6 ml in the control group and by 16.7 ± 30.5 ml in the pooled pacing groups during follow-up (adjusted mean difference [95% confidence interval] = 0.6 [−12.3, 13.5] ml, p = 0.92). There were also no significant between-group differences in the change in LV end-systolic volume or ejection fraction over time. Quality of life, as assessed by the Minnesota Living with Heart Failure and European Quality of Life-5 Dimension questionnaires and New York Heart Association class, was also similar between groups during 18-month follow-up. Six-minute walk distance improved during follow-up to an equal degree between groups, and there were no significant differences in the 18-month rates of death or heart failure hospitalization between the pooled pacing therapy vs. control groups (17.4 vs. 21.7%, respectively, p = 0.59).
The authors concluded that peri-infarct pacing did not prevent LV remodeling or improve functional or clinical outcomes during 18-month follow-up in patients with a large first MI.
This trial reports that peri-infarct pacing did not attenuate the increase in LVEDV that may occur in patients with a large MI, and did not improve functional or clinical outcomes during 18-month follow-up. The neutral effects of peri-infarct pacing on LV size and function were reflected in similar outcomes between groups in quality of life as measured by serial assessments and mortality, and heart failure hospitalization outcomes were also similar during follow-up between groups. Overall, the results of PRomPT, along with the MENDMI trial, do not support a role for peri-infarct pacing in large MI.
< Back to Listings