In patients with STEMI, shorter delay to primary PCI (PPCI) is associated with lower risk for readmissions or outpatient contacts due to congestive heart failure (CHF) during follow-up, according to a study published Sept. 20 in the Annals of Internal Medicine.
In patients with STEMI, delay between contact with the healthcare system and initiation of reperfusion therapy (system delay) is associated with mortality, but the study authors noted that the data on the associated risk for CHF among survivors are limited.
Thus, Christian Juhl Terkelsen, MD, PhD, from Aarhus University Hospital, Aarhus, Denmark, and colleagues sought to evaluate the association between system delay and the risk for readmissions or outpatient contacts due to CHF after primary PCI in patients with STEMI through a historical follow-up study using population-based medical registries in Western Denmark.
The researchers assessed 7,952 patients with STEMI who were transported by emergency medical service from Jan. 1, 1999, to Feb. 7, 2010, and treated with primary PCI within 12 hours of symptom onset and who had a system delay of six hours or less. The median duration of follow-up was 3.1 years.
They determined the cumulative incidence of readmissions or outpatient contacts due to CHF by using competing risk regression analysis, with death as the competing risk. Crude and adjusted cause-specific hazard ratios for readmissions or outpatient contacts due to CHF were determined for system delay and other covariates.
Terkelsen and colleagues reported that system delays of 60 minutes or less (451 patients), 61 to 120 minutes (3,457 patients), 121 to 180 minutes (2,655 patients) and 181 to 360 minutes (1,389 patients) corresponded with long-term risks for readmissions or outpatient contacts due to CHF of 10.1 percent, 10.6 percent, 12.3 percent and 14.1 percent, respectively.
In a multivariable analysis, system delay was an independent predictor of readmissions or outpatient contacts due to CHF (adjusted hazard ratio per hour increase in delay, 1.10), according to the researchers.
Acknowledging the limitations of the study, the authors said that in any nonrandomized study, there are risks for selection bias and residual confounding.
The Karl G. Andersen Foundation, the Helga and Peter Korning Foundation, the Health Research Fund of Central Denmark Region, the Research Foundation at Skejby University Hospital, the Riisfort Foundation and the Arvid Nilsson Foundation funded the study.