Isovolumic relaxation flow detected by doppler echocardiography in patients undergoing right ventricular pacing

Intraventricular Isovolumic Relaxation Flow Patterns Studied by Using Vector Flow Mapping

“…The IRF propagation velocity is a preload‐independent Doppler parameter in the assessment of LV diastolic function . Deteriorated global LV systolic and diastolic performance, abnormal regional myocardial contraction and relaxation, and changes in ventricular electrical activation may alter the IRF pattern …”

“…The color M‐mode Doppler, pulsed‐wave Doppler, and continuous wave Doppler echocardiographies, with their high sampling rates, have been used to measure peak velocity, direction, and duration of IRF. However, these methods provide only one‐dimensional velocity information on the M‐mode or Doppler cursor; therefore, they are insufficient in the identification of intraventricular flow in both temporal and spatial distributions.…”

“…Isovolumic relaxation flow (IRF) in the left ventricle (LV) has been reported in normal subjects, 1,2 as well as in patients with diverse cardiac diseases, such as ischemic heart disease, [3][4][5][6][7][8][9][10][11] right ventricular pacing, [12][13][14] ventricular preexcitation, 15 and chronic renal failure. 16 IRF has been described as an apically directed, basally directed, or bidirectional flow occurring in the isovolumic relaxation (IVR) period.…”

Immediate impairment of left ventricular mechanical performance and force–frequency relation by rate-responsive dual-chamber, but not atrial pacing: Implications from intraventricular isovolumic relaxation flow

“…The intraventricular flow driven by the pressure gradient generated from the physiologic nonuniformity can be used to investigate the disruption of ''optimal tuning'' of cardiac muscle-pump performance in various pathologic conditions [5,6]. Using the continuous wave Doppler echocardiography, previous studies have shown the intraventricular flow during isovolumic relaxation produced by right ventricular pacing [7,8]. The color M-mode echocardiography, having the advantage of temporal and spatial resolution, can describe the influence on isovolumic relaxation flow by disrupted nonuniformity more instructively than the conventional Doppler method [6,9].…”

High Prevalence of Isovolumic Relaxation Flow in Healthy Subjects

“…Since left ventricular isovolumic relaxation flow (IRF) was first demonstrated by Kuroiwa et al 1 in 1985, it has been reported to be present in normal subjects, 2,3 patients with various cardiovascular diseases, 4–7 including hypertrophic cardiomyopathy, aortic valve disease, hypertension, ischemic heart disease, and ventricular preexcitation, and those undergoing right ventricular pacing 8 . Our recent study suggests the role of inhomogenous left ventricular activation–inactivation in the genesis of segmental early relaxation and in turn of IRF 7 .…”