Assessment of left ventricular function in ischemic heart disease. The relation between pressure decay during the isovolumic relaxation phase and regional wall motion abnormality

Regional diastolic function in effort angina pectoris: assessment with biplane left ventriculography

To investigate left ventricular (LV) regional diastolic function in effort angina pectoris (AP), we performed left ventriculography in 14 patients with AP and isolated left anterior descending artery disease and in 9 normal subjects (N). LV volume (V), regional area (S) [anterior, apex, and inferior], and the first derivative of V and S (dV/dt, dS/dt) were derived from analysis of the left ventriculogram. Normalized peak filling rate (nPFR) and peak atrial filling rate (nPAFR) were derived from dV/dt. The ratio of filling volume to stroke volume during rapid filling and atrial contraction were defined as rapid filling fraction (RFF) and atrial filling fraction (AFF). Similarly, peak area changing rate (PACR), peak area changing rate during atrial contraction (PACRac), rapid area changing fraction (RACF), and atrial area changing fraction (AACF) were derived from S and dS/dt. We also calculated the time constant of LV relaxation (T), and LV global and regional compliance during atrial contraction [(dV/VdP)ac, (dS/SdP)ac]. The LV global diastolic function (T increases, nPFR decreases) was impaired in the angina patients. LV regional diastolic function (nPACR decreases, RACF decreases) was also impaired in the affected region of the AP group. While their rapid filling was impaired, nPACRac was maintained and AACF was increased in the affected region. Furthermore, nPACR and RACF each showed a significant inverse correlation with AACF in the anterior region [r = -0.57 (P < 0.01), r = -0.92 (P < 0.001)]. In the affected region of the patients with AP, (dS/SdP)ac was increased, but not significantly. Thus, LV global and regional diastolic functions were simultaneously impaired in patients with isolated left anterior descending artery disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Single-beat estimation of the slope of the end-systolic pressure-volume relation in the human left ventricle

This study assessed a new method of estimating the slope (Ees) of the end-systolic pressure-volume relation (ESPVR) from a single beat of the human heart. Left ventricular pressure was recorded with a high-fidelity micromanometer in patients with heart disease during left ventriculography. Peak isovolumic pressure at the end-disastolic volume was estimated by a curve-fitting technique from an isovolumic left ventricular pressure curve. The ESPVR line was drawn from the estimated peak isovolumic pressure-volume point tangential to the left upper corner of the pressure-volume loop. The slope of this estimated ESPVR line from single-beat analysis was compared with the slope of the ESPVR line obtained from three pressure-volume loops in 16 patients given angiotensin II or nitroglycerin infusion. The estimated Ees was 5.0 +/- 2.2 mm Hg/ml/m2, and the conventional Ees was 4.9 +/- 2.7 mm Hg/ml/m2. The estimated Ees showed a positive correlation with the conventional Ees (r = 0.91, p less than 0.001, SEE = 1.2 mm Hg/ml/m2). In the other 13 patients, after dobutamine infusion (5 micrograms/kg/min i.v.) the estimated Ees increased significantly from 5.6 +/- 1.4 to 7.4 +/- 2.0 mm Hg/ml/m2 (p less than 0.01). Thus, the estimated Ees approximated the conventional Ees and was sensitive to a positive inotropic intervention. We conclude that this single-beat analysis method facilitates assessment of the beat-by-beat ESPVR of the human heart.

Effects of left ventricular asynchrony on time constant and extrapolated pressure of left ventricular pressure decay in coronary artery disease

To elucidate the effects of ventricular asynchrony with or without myocardial ischemia on the time constant of left ventricular pressure decay and asymptote, that is, the level to which pressure would decrease if isovolumic pressure decrease continued infinitely, left ventriculography and pressure measurements were investigated in 14 normal subjects and 25 patients with coronary artery disease. Ventricular asynchrony was quantitated by the segmental area-time curve. This study consisted of two parts. 1) After a right atrial pacing stress test, the time constant and asymptote remained unchanged in eight normal subjects. In 18 patients with coronary artery disease and pacing-induced angina, asynchrony increased, the time constant was prolonged (64 +/- 13 to 94 +/- 17 ms, p less than 0.01) and the asymptote decreased (-22 +/- 10 to -46 +/- 20 mm Hg, p less than 0.01) after the pacing. 2) During right ventricular pacing at 80, 100 and 120 beats/min in the patients, asynchrony increased and the time constant was prolonged (55 +/- 7 versus 70 +/- 10, 47 +/- 11 versus 66 +/- 19, 36 +/- 7 versus 53 +/- 13 ms, respectively, p less than 0.01 versus right atrial pacing), whereas the asymptote was unchanged in six normal subjects compared with the value during right atrial pacing at each pacing rate. In seven patients with coronary artery disease, right ventricular pacing at 80, 100 and 120 beats/min also produced an increase in the time constant, while the asymptote was unchanged. Thus, prolongation of the time constant of left ventricular pressure decay may result from ventricular asynchrony even in the absence of myocardial ischemia.(ABSTRACT TRUNCATED AT 250 WORDS)

The relation between left ventricular asynchrony, relaxation, outward wall motion and filling characteristics during control period and pacing-induced myocardial ischaemia in coronary artery disease

To assess the relation between left ventricular asynchrony, relaxation, outward wall motion and filling in patients with coronary artery disease and normal systolic function, pressure measurements and left ventricular angiography were performed at rest and after pacing. Asynchrony and outward wall motion were quantified by segmental area-time curves. At rest, there were no differences in asynchrony and time constant between 10 patients with coronary artery disease and 10 normal subjects, while the early-filling rate was less in patients with coronary artery disease than in normal subjects. Six coronary artery disease patients with isolated left anterior descending disease displayed anterior outward wall motion which was less than that of normal subjects. In 10 coronary artery disease patients with pacing-induced angina, asynchrony increased, time constant prolonged and the early-filling rate decreased. In 6 coronary artery disease patients with isolated left anterior descending disease, anterior outward wall motion decreased after pacing. Thus, impaired early diastolic filling at rest in patients with coronary artery disease and normal systolic function may result not from asynchrony nor impaired relaxation, but from reduced regional outward wall motion of the affected area supplied by diseased coronary artery during early diastole. However, during ischaemia temporal asynchrony and impaired relaxation possibly add to left ventricular filling impairment in patients with coronary artery disease.