SBP may predict heart failure, death risk after cardiac resynchronization therapy
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.”