Diastolic dysfunction and survival in patients with preserved or mildly reduced left ventricular ejection fraction

Abstract Background Left ventricular ejection fraction (LVEF) is relatively indiscriminate for prognosis in patients with preserved or mildly reduced LVEF (>40%) following myocardial infarction (MI). Aims This study sought to determine the value of guideline-based assessment of diastolic dysfunction (DD) in predicting all-cause and cardiac mortality in patients with a first-ever MI and LVEF>40%. Methods A retrospective single centre study involving 2234 patients with a first-ever MI (STEMI or NSTEMI) with LVEF>40% was performed. Clinical, angiographic, and echocardiographic data were obtained from prospectively maintained institutional databases. Outcomes data were obtained from the state-wide registry. Echocardiography was performed early post-admission for all patients. Significant diastolic dysfunction (DD) was defined as grade 2+3 diastolic dysfunction according to current American Society of Echocardiography/ European Association of Cardiovascular Imaging guidelines. Results The mean age of patients was 61.4±12.3 years, 70.7% were males, and 12.1% had 3-vessel disease. The mean LVEF was 55.8±7.2% and 9.1% had significant DD. At a median follow up of 4.5 years, there were 219 deaths (46 cardiac deaths). On Cox proportional hazards multivariable analyses incorporating significant clinical, angiographic, and echocardiographic variables, significant DD was an independent predictor of both all-cause (HR 2.01,95%CI 1.37-2.94, p<0.001) and cardiac (HR 3.97,95%CI 1.98-7.99, p<0.001) mortality. Conclusions Significant DD is an independent predictor of all-cause and cardiac mortality following MI in patients with preserved or mildly reduced LVEF and thus effectively re-stratifies prognosis in a subgroup where the LVEF is relatively indiscriminate for survival. The benefit of further investigation and/or treatment in this subgroup needs further study.