Background: Heart failure is a common complication after myocardial infarction (MI) and is associated with increased mortality. Whether remote heart failure symptoms assessment after MI can improve risk stratification is unknown. The authors evaluated the association of the 23-item Kansas City Cardiomyopathy Questionnaire (KCCQ) with all-cause mortality after MI.
Methods and results: Prospectively collected data from consecutive patients hospitalized for MI at a large tertiary heart center between June 2017 and September 2022 were used. Patients remotely completed the KCCQ 1 month after discharge. A total of 1135 (aged 64±12 years, 26.7% women) of 1721 eligible patients completed the KCCQ. Ranges of KCCQ scores revealed that 30 (2.6%), 114 (10.0%), 274 (24.1%), and 717 (63.2%) had scores <25, 25 to 49, 50 to 74, and ≥75, respectively. During a mean follow-up of 46 months (interquartile range, 29-61), 146 (12.9%) died. In a fully adjusted analysis, KCCQ scores <50 were independently associated with mortality (hazard ratio [HR], 6.05 for KCCQ <25, HR, 2.66 for KCCQ 25-49 versus KCCQ ≥50; both P<0.001). Adding the 30-day KCCQ to clinical risk factors improved risk stratification: change in area under the curve of 2.6 (95% CI, 0.3-5.0), Brier score of -0.6 (95% CI, -1.0 to -0.2), and net reclassification improvement of 0.71 (95% CI, 0.45-1.04). KCCQ items most strongly associated with mortality were walking impairment, leg swelling, and change in symptoms.
Conclusions: Remote evaluation of heart failure symptoms using the KCCQ among patients recently discharged for MI identifies patients at risk for mortality. Whether closer follow-up and targeted therapy can reduce mortality in high-risk patients warrants further study.
Keywords: KCCQ; heart failure; mortality; myocardial infarction; prognosis; symptoms.