Systolic blood pressure (SBP) following cardiac resynchronization therapy may help facilitate patient stratification according to mortality and heart failure risk, a recent study has found.
Researchers enrolled 1,000 patients who had undergone cardiac resynchronization therapy. The study outcomes included heart failure admission or death, whichever came first, at 1 year. Rates were compared between those with low (<110 mm Hg) and preserved (≥110 mm Hg) SBP.
Most of the participants had preserved SBP at 1 year (n=800; mean age, 65.0±10.4 years; 25 percent female); only 200 (mean age, 62.3±11.9 years; 26 percent female) had low SBP. Those with preserved SBP tended to be older, were less likely to be smokers and had less advanced echocardiographic features.
Kaplan-Meier survival analysis revealed that those with preserved SBP 1 year after resynchronization therapy had lower rates of death or heart failure relative to their comparators with reduced SBP (2-year event rates: 12 percent vs 20 percent; p=0.009).
Multivariate Cox proportional hazards regression analysis confirmed this, showing a 29-percent lower risk of heart failure or death in those with preserved SBP (hazard ratio [HR], 0.71, 95 percent confidence interval, 0.52–0.95; p=0.024). When taken as a continuous variable, each 5-mm Hg increase in SBP cut the risk of heart failure or death by 7 percent (p=0.008).
“We used one-time office SBP measurements that were not standardized among the various enrollment centres,” said the researchers. “While this approach may replicate clinical practice, a prespecified, standardized protocol for SBP measurement is likely needed to estimate true effect of SBP change on the primary outcome.”