Prognostic value of changes in coronary blood flow in patients with preserved ejection fraction

BACKGROUND: The measurement of the left ventricular ejection fraction during at echocardiographic study evaluates global contractility. A decrease in this parameter indicates a poor prognosis. However, in the range of normal values, the left ventricular ejection fraction loses prognostic significance. This category of patients requires the development of other prognostic methods.

AIM: To explore the effect of changes in coronary blood flow parameters measured using dopplerography in patients with preserved left ventricular ejection fraction in predicting adverse outcomes over the next year.

MATERIALS AND METHODS: The prospective study included patients referred for echocardiography in 2019–2020 followed up at the Saint Petersburg Research Center of Cardiology “Medika”. The inclusion criterion was age over 18 years. A decrease in left ventricular ejection fraction of less than 53% was an exclusion critrion. In addition to standard echocardiography, dopplerography has been used to study the velocity parameters of blood flow in the coronary arteries. The observation period was 1 year.

RESULTS: The control group included 453 patients. During the year of observation, 89 cases of spontaneous adverse events (death / myocardial infarction / progressive heart failure) occurred, including 19 deaths. The patients who died were older (76.6 ± 8.6 vs. 59.3 ± 15.5 years; р < 0.000001), with lower global longitudinal function (−13.8 ± 4.3% vs. −18.3 ± 3.6%, р < 0.000001), with a large volume index of the left atrium (54.6 ± 15.5 vs. 36.5 ± 13.1 ml/m²; р < 0.000000), high pressure in the pulmonary artery (39 ± 14.7 vs. 29.5 ± 8.1 mmHg; р < 0.000000), high left ventricular myocardial mass index (108.7 ± 37.2 vs. 88,1 ± 24.1 g/m², р < 0.000000) and impaired diastolic function [the ratio of blood flow velocity through the mitral valve in the first (early) phase of left ventricular filling and the average velocity of the mitral valve fibrous ring 13.6 ± 7.1 vs. 9.4 ± 4.4; р < 0.000000]. The blood flow velocity in the anterior interventricular artery was significantly higher (78.0 ± 39.0 vs. 50.0 ± 25.4 cm/s, р < 0.000007). Only age and flow velocity in anterior interventricular artery were independent predictors of death / myocardial infarction (р < 0.004).

CONCLUSIONS: Velocity parameters in the anterior interventricular artery are a significant predictor of short-term spontaneous events, including death, in patients with preserved ejection fraction.