Cancer, chronic diseases and other non-cardiac conditions are now the leading causes of death after PCI, a shift away from cardiac causes that has occurred over the past two decades, according to a study published online Feb. 10 in Circulation.
Daniel B. Spoon, MD, of the Mayo Clinic in Rochester, Minn., and co-investigators looked at data from patients who underwent PCI between 1991 and 2008. Of the 19,982 consecutive patients who underwent the procedure, 19,077 were discharged alive and consented to participate.
The researchers divided those patients into six-year time periods to analyze mortality trends (1991-1996, 1997-2002 and 2003-2008) and determined cause of death using telephone interviews, medical records, autopsy reports and death certificates. Their final follow-up date was Dec. 31, 2012.
Of the 19,077 patients in the study, 6,988 died later (37 percent). The investigators were able to determine the cause of death in 6,857 patients (98.1 percent). Over the three time periods, death from cardiac causes decreased by 33 percent at five years after PCI, but there was a 57 percent increase in non-cardiac deaths.
The trends were independent of other variables, including age, severity of coronary artery disease or the reason for PCI. The decline in cardiac mortality was also independent of baseline clinical characteristics.
The decline in cardiac deaths was primarily attributed to a decline in mortality from fatal MI/sudden cardiac death. Death from heart failure did not change over time. Cancer and chronic diseases drove the increase in non-cardiac causes of death.
The authors explained that a possible explanation for the decrease in cardiac deaths after PCI could be the increased use of preventive therapies prior to discharge, such as statins and ACE inhibitors that lower the long-term risk of MI and sudden death in patients with coronary artery disease. They also noted that other contributory factors could be a higher average PCI age and a higher prevalence of non-cardiac comorbidities.
“The findings underscore the importance of a holistic approach in the care of patients with coronary artery disease and provide cause-specific mortality benchmarks to assess the future impact of survival-directed therapies,” they wrote.