Force-frequency relationship as a predictor of long-term prognosis in patients with heart diseases.
Adequate evaluation of the nature of the residual failing myocardium, as well as the severity of myocardial injury, is important for managing patients with heart failure. The aim of this study was to investigate the myocardial function and the prognosis of patients with heart diseases using the force-frequency relationship (FFR). We enrolled 76 patients with sinus rhythm who had miscellaneous heart diseases and performed incremental right atrial pacing at the time of diagnostic cardiac catheterization. The first derivatives of left ventricular pressure (dP/dt) were recorded using a micro manometer-tipped catheter during the study. To represent properties of FFR, two parameters-the peak force rate (PFR) and force gain (FG)-were estimated. PFR was defined as the heart rate at which dP/dt became maximum. FG was defined as the difference between dP/dt at PFR and dP/dt at the basal heart rate. FG decreased as the severity of left ventricular (LV) dysfunction increased (372.0 ± 110.7, 209.5 ± 29.1 and 116.3 ± 13.1 mmHg/s for normal LV function, mild LV dysfunction and severe LV dysfunction groups, P < 0.05, respectively). PFR correlated with cardiac index (r = 0.375, P = 0.001). FG correlated with LV end systolic volume index (r = -0.297, P = 0.010) and LV ejection fraction (r = 0.539, P < 0.001). Furthermore, pulmonary arterial wedge pressure [hazard ratio (HR) 1.126, P < 0.01] and FG (HR 0.992, P = 0.061) tended to be independent predictors for cardiovascular death. Analysis of FFR, especially FG, seems to be useful to evaluate the nature of the failing myocardium and the prognosis of patients with heart diseases.
Tanaka
Komei
K
Division of Cardiology, Department of Cardiovascular and Vital Control, Niigata University Graduate School of Medical and Dental Sciences, 1-754 Asahimachi-dori, Chuo-ku, Niigata, 951-8510, Japan. komei@me.com
Kodama
Makoto
M
Ito
Masahiro
M
Hoyano
Makoto
M
Mitsuma
Wataru
W
Ramadan
Mahmoud M
MM
Kashimura
Takeshi
T
Hirono
Satoru
S
Okura
Yuji
Y
Kato
Kiminori
K
Hanawa
Haruo
H
Aizawa
Yoshifusa
Y
D016280:Atrial Function, Right; D006328:Cardiac Catheterization; D002304:Cardiac Pacing, Artificial; D005260:Female; D006333:Heart Failure / Q000175:diagnosis / Q000401:mortality / Q000503:physiopathology* / Q000628:therapy; D006339:Heart Rate; D006801:Humans; D007564:Japan; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction; D011237:Predictive Value of Tests; D011379:Prognosis; D016016:Proportional Hazards Models; D011669:Pulmonary Wedge Pressure; D018570:Risk Assessment; D012307:Risk Factors; D012720:Severity of Illness Index; D013318:Stroke Volume; D013997:Time Factors; D018487:Ventricular Dysfunction, Left / Q000175:diagnosis / Q000401:mortality / Q000503:physiopathology* / Q000628:therapy; D016277:Ventricular Function, Left; D017725:Ventricular Pressure