PROGNOSTIC VALUE OF HEART RATE TURBULENCE FOR PREDICTION OF THE VENTRICULAR ARRHYTHMIC EVENT IN PATIENTS WITH HEART FAILURE PRESERVED EJECTION FRACTION
Introduction: The aim of the study was to define prognostic value of heart rate turbulence (HRT) for prediction of the ventricular arrhythmic event in patients with heart failure preserved ejection fraction (HFPEF).
Material and method: The study comprised 100 participants. The study group consisted of 50 hypertensive patients (aged 47-80) with heart failure symptoms (NYHA class II-IV), with preserved left ventricular systolic function (LVDd: 6,0 cm, LVEF 45%) and echocardiographic indicators of impaired diastolic function. Control group consisted of 50 hypertensive patients without symptoms of heart failure 24-hours ECG Holter monitoring was performed. An analysis of HRT was performed using an algorithm adopted from the literature. Both turbulence onset (TO) and turbulence slope (TS) were assessed.
Results: In the study group TO values were as followed: –5,25% do 3,64% (mean value.–1,134 +/- 1,823%), TS values were between 0,938 and 20,0 ms/R-R (mean value. 6,791 +/- 4,90 ms/R-R). Statistically significant negative correlation were determined between TO i TS parameters (r=-0,385; p=0,0907). There were 5 patients with non-sustained ventricular tachycardia (nsVT) among HFPEF group (10% of study group) In the arrhythmic event group depression of heart rate turbulence phenomenon was determined, as higher values of TO and lower values of TS were observed comparing to control group (without ventricular arrhythmia) TO values in the control group range between -7,92% and 3,1% (mean value –1,074 +/- 2,186%), and TS were between 1,611 and 33,0 ms/R-R (mean value.8,396 +/- 6,918 ms/R-R).
- In the HFPEF patients with arrhythmic episodes, HRT depression is determined. That confirmes higher risk of sudden cardiac events among HFPEF patients. Also this observation confirmes prognostic value of HRT for sudden cardiac events.
- In HFPEF group significant negative correlation is determined between TO i TS, and that fact confirmes correlation between both parameters. Among HRT parameters turbulence slope (TS) is to be predominant prognostic factor and reflects better baroreflex reactivity comparing to turbulence onset (TO).