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1.
Left ventricular (LV) diastolic filling is abnormal at rest in many patients with coronary artery disease (CAD), even in the presence of normal resting LV systolic function. To determine the effects of improved myocardial perfusion on impaired. LV diastolic filling, we studied 25 patients with one-vessel CAD by high-temporal-resolution radionuclide angiography before and after percutaneous transluminal coronary angioplasty (PTCA). No patient had ECG evidence of previous myocardial infarction. Despite normal regional and global LV systolic function at rest in all patents, LV diastolic filling was abnormal (peak LV filling rate [PFR] less than 2.5 end-diastolic volumes (EDV)/sec or time to PFR greater than 180 msec) in 17 of 25 patients. Twenty-three patients had abnormal LV systolic function during exercise. After successful PTCA, LV ejection fraction and heart rate at rest were unchanged, but LV ejection fraction during exercise increased, from 52 +/- 8% (+/- SD) to 63 +/- 5% (p less than 0.001). LV diastolic filling at rest improved: PFR increased from 2.3 +/- 0.6 to 2.8 +/- 0.5 EDV/sec (p less than 0.001) and time to PFR decreased from 181 +/- 22 to 160 +/- 18 msec (p less than 0.001). Thus, a reduction in exercise-induced LV systolic dysfunction after PTCA, reflecting a reduction in reversible ischemia, was associated with improved LV diastolic filling at rest. These data suggest that in many CAD patients with normal resting LV systolic function and without previous infarction, abnormalities of resting LV diastolic filling are not fixed, but appear to be reversible manifestations of impaired coronary flow.  相似文献   

2.
Impaired left ventricular (LV) diastolic filling at rest is frequently observed in patients with coronary artery disease (CAD) who have normal LV systolic function and no previous infarction. To test the hypothesis that abnormal diastolic function at rest might reflect the functional severity of CAD, as estimated by exercise-induced ischemia, the relation between regional and global LV diastolic function at rest and during exercise-induced ischemia was evaluated in 49 patients with radionuclide angiography. All patients had normal systolic function at rest. Group 1 (n = 26) patients manifested a normal ejection fraction response to exercise and group 2 (n = 23) patients an abnormal response. Data obtained from 22 age-comparable normal volunteers were used for comparison. Although regional and global diastolic function were not different between normal subjects and group 1 patients, peak filling rate was lower in group 2 patients than in normal subjects (2.5 +/- 0.8 vs 3.2 +/- 0.6 end-diastolic counts/s; p less than 0.01). Moreover, regional diastolic asynchrony, as assessed from the radionuclide data by using a regional sector analysis of the LV region of interest, was greater in group 2 patients (46 +/- 44 ms) than in both normal subjects (25 +/- 16 ms; p less than 0.05) and group 1 patients (23 +/- 16 ms; p less than 0.05). Thus, among patients with CAD and with normal LV systolic function at rest, impaired LV filling and regional asynchrony predict a greater degree of exercise-induced ischemia, suggesting a greater extent of jeopardized myocardium.  相似文献   

3.
To evaluate whether the extent of left ventricular (LV) asynchrony plays a role in the impairment of LV rapid filling in patients with coronary artery disease (CAD), 48 patients underwent both radionuclide angiography and cardiac catheterization. Patients were divided into group I (n = 33), with normal LV kinesis or only mild hypokinesia, and group II (n = 15), with LV dyskinesia or akinesia. Radionuclide ejection fraction was higher in group I than in group II (62 +/- 12 vs 44 +/- 20%; p less than 0.001). Peak filling rate was significantly lower in group II (1.9 +/- 0.8 vs 2.6 +/- 0.9 end-diastolic counts/s; p less than 0.01). Time to end-systole coefficient of variation, an index of the extent of LV asynchrony, was significantly higher in group II than in group I (43 +/- 10 vs 35 +/- 6; p less than 0.0002). In group I, a highly significant inverse relation was found between this index of asynchrony and peak filling rate (r = 0.71; p less than 0.0001). This correlation was found even when time to end-systole coefficient of variation was normalized to the RR interval (r = 0.49; p less than 0.01) and when peak filling rate was expressed in stroke counts (r = 0.57; p less than 0.001). The correlation between peak filling rate and index of asynchrony was maintained up to an end-systole coefficient of variation value of approximately 35. In group II patients (most with an asynchrony value greater than or equal to 35) no relation was found between time to end-systole coefficient of variation and peak filling rate.  相似文献   

4.
It has been suggested that the rate of left ventricular (LV) relaxation is related to the inotropic state, end-systolic fiber length and peak LV pressure, but little information is available regarding the rate of LV relaxation in patients with coronary artery disease (CAD) and LV dysfunction. To assess the rate of LV relaxation we obtained high-fidelity LV pressure measurements with manometer-tip catheters in 39 patients. The signal was analyzed by a digital computer to yield the maximal rate of pressure rise (pos dP/dt) and the maximal rate of pressure fall (neg dP/dt). Selective coronary arteriography and biplane LV angiography with determination of LV volumes, ejection fraction (EF) and percent abnormally contracting segments (ACS) when present, were performed in all patients. In 10 patients with normal LV function (EF greater than 0.50, no asynergy) mean neg dP/dt (2074 +/- 121 mm Hg/sec) was significantly (p less than 0.01) greater than in 29 patients with CAD and LV dysfunction (1695 +/- 66 mm Hg/sec). In nine patients with LV dysfunction and EF less than 0.35, mean neg dP/dt was reduced to 1405 +/- 107 mm Hg/sec, significantly (p less than 0.01) lower than in patients with normal LV function. Neg dP/dt correlated well with pos dP/dt (r = 0.75), with EF (r = 0.74), and with ACS (r = -0.74), and less well with LV end-systolic volume (r = 0.67). There was very poor correlation between neg dP/dt and peak LV pressure (r = 0.30). These data suggest that the rate of LV relaxation, as assessed by neg dP/dt, is impaired in patients with CAD and LV dysfunction, and the extent of impairment is related to the severity of the dysfunction as determined hemodynamically by pos dP/dt, and angiographically by EF and ACS. In these patients the maximal rate of LV relaxation is inversely related to LV end-systolic volume, and is not related to peak LV pressure.  相似文献   

5.
To assess the relation between myocardial ischemia, ventricular arrhythmias (VA), and left ventricular (LV) dysfunction, we evaluated 74 patients with coronary artery disease (CAD) using radionuclide angiography (to determine the resting ejection fraction [EF]), resting thallium-201 scintigraphy (to ascertain the extent of resting ischemia), and 24-hour Holter monitoring (to assess VA). Thirty patients had resting ischemia, 26 had resting EF less than 30%, and 27 had repetitive VA. Patients with and without ischemia had similar EFs (36 +/- 14 vs 38 +/- 14, p = NS). Further, patients with and without repetitive forms of VA had a similar number of resting ischemic segments (1.1 +/- 1.7 vs 1.1 +/- 2.2, p = NS). Patients with EFs less than 30 had more VA than patients with EFs greater than or equal to 30 (Holter class 4.3 +/- 2.3 vs 3.0 +/- 1.8, p less than 0.01) but a similar extent of ischemia (1.4 +/- 2.2 vs 1.0 +/- 1.7, p = NS). Thus, while patients with lower EFs have more repetitive forms of VA, ischemia at rest is independent of VA and EF. These data suggest that prognostic stratification of patients with CAD for intervention studies should include a separate consideration of ischemia.  相似文献   

6.
To study the effect of mild-to-moderate elevations in diastolic blood pressure (BP) on systolic left ventricular (LV) function, 28 hypertensive patients and 20 normal subjects underwent upright exercise first-pass radionuclide angiography. All were asymptomatic, had normal rest and exercise electrocardiographic findings and no evidence of LV hypertrophy or coronary artery disease. LV function at rest was similar in the 2 groups, but with exercise hypertensive patients had a greater end-systolic volume (69 +/- 19 vs 51 +/- 19 ml, p less than 0.002) and lower ejection fraction (EF) (0.59 +/- 0.09 vs 0.72 +/- 0.07, p less than 0.0001), stroke volume (101 +/- 28 vs 130 +/- 36 ml, p less than 0.005) and peak oxygen uptake (23 +/- 7 vs 33 +/- 9 ml/kl/min, p less than 0.05). Hypertensive patients were separated into 3 groups: group 1-12 patients with an increase in EF with exercise greater than or equal to 0.05; group 2-7 patients with a change in EF with exercise less than 0.05; and group 3-9 patients with a decrease in EF with exercise greater than or equal to 0.05. Group 3 hypertensive patients were older, had a higher heart rate at rest and lower peak oxygen uptake. Rest LV function was similar in the 3 hypertensive subgroups, but exercise end-systolic volumes were higher in groups 2 and 3. Exercise thallium-201 images was normal in all but 1 of 14 hypertensive group 2 or 3 patients.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

7.
Because of discrepancy in interpretation of early diastolic filling indices in normal subjects and hypertensive, we studied the correlations between age and radionuclide angiographic peak filling rate (PFR), doppler echocardiographic early E and late A waves, left ventricular mass (LVM), blood pressure (BP) and ejection fraction (EF) in cautiously screened 30 untreated hypertensive and 30 age paired normal subjects (mean of age 52 +/- 17 ranging from 34 to 78 years). No patient had gross obesity nor coronary artery disease. Univariate analysis revealed strong correlations between LV filling and age in normal (r = -0.82 p less than 0.0001) and hypertensive (r = -0.61 p less than 0.001), with a very significant difference in y intercepts (t = 0.61 p = 10(-6)). LVM correlated poorly with age (r = 0.35 p less than 0.05) but with none of the LV filling indexes. BP correlated with PFR (r = 0.33 p less than 0.05) and A wave (r = 0.44 p less than 0.02) in hypertensive only. After multivariate analysis, significant dependencies of PFR, age, LV mass were more accurate if BP was in a higher range. The variability of the values of LV filling indexes was wider in hypertensive than in normotensive. Normotensive aging and hypertension have similar effects on the cardiovascular system. In the most aged people even without apparent cardiac disease, it is not possible to identify the specific effects of hypertension on diastolic function.  相似文献   

8.
Racial differences in cardiac structure and function were evaluated in 62 black and 71 white healthy young adults. Left ventricular (LV) mass index, relative wall thickness, fractional shortening, resting cardiac index and resting systemic vascular resistance index were estimated using M-mode echocardiography. Pulsed Doppler interrogation of transmitral flow was used to characterize LV filling. Average daytime blood pressure (BP) was determined by ambulatory monitoring during a typical work or school day. Ambulatory daytime BP averaged 127 +/- 12/80 +/- 7 mm Hg in black subjects, and 127 +/- 9/80 +/- 6 mm Hg in white subjects (p = not significant). The 2 groups were also similar in resting BP, age and gender composition. Relative wall thickness was significantly greater in black than in white subjects (0.37 +/- 0.06 vs 0.34 +/- 0.05; p less than 0.01). This difference was found in both men and women. Black subjects also had a higher resting systemic vascular resistance index (2,110 +/- 570 vs 1,920 +/- 500 dynes.s.cm-5.m2; p less than 0.05) and lower resting cardiac index (3.14 +/- 0.84 vs 3.46 +/- 0.85 L/min/m2; p less than 0.05). There were no significant differences between black and white subjects in LV mass index, fractional shortening and normalized peak filling velocity. These results suggest that racial differences in LV structure and systemic hemodynamics exist even in patients without sustained hypertension. In our study population, the greater relative wall thickness in black subjects was not accompanied by significant differences in LV systolic function or diastolic filling.  相似文献   

9.
10.
In this study we examined the left ventricular pressure/volume relationship in 39 patients with moderate or severe aortic regurgitation (AR) and 15 normal subjects. The patients with AR were divided into two groups; patients with normal resting ejection fraction (EF greater than or equal to 50%, group I, n = 21) and patients with abnormal EF (group II, n = 18). The patients in group I were younger (p less than 0.005), exercised to a higher workload, and had better exercise tolerance than patients in group II (p less than 0.01). The patients' exercise heart rate and blood pressure were not significantly different between the two groups. During exercise tests nine patients in group I and seven patients in group II had normal EF response (greater than or equal to 5% increase) (p = NS). The peak systolic blood pressure to end-systolic volume index ratio (SBP/ESVI) was higher in normal subjects than in patients in groups I and II, at rest it was (4.3 +/- 1.0 vs 2.6 +/- 1.2 vs 1.6 +/- 0.8, respectively, p less than 0.0001) and during exercise it was (7.6 +/- 1.8 vs 4.2 +/- 1.4 vs 2.6 +/- 1.3, respectively, p less than 0.0001). The resting SBP/ESVI ratio was below the lower normal limit in 12 patients (57%) in group I and in 16 patients (89%) in group II. Also, the exercise SBP/ESVI ratio was below the lower normal limit in 17 patients (81%) in group I and all of the patients (100%) in group II. Multivariate discriminant analysis identified the change in SBP/ESVI (F = 34.8) and resting end-diastolic volume (F = 6.7) as independent predictors of the EF response to exercise. Thus, most patients with AR, including those with normal resting EF or normal EF response to exercise, have abnormal SBP/ESVI at rest or during exercise.  相似文献   

11.
Doppler mitral flow indexes and their relation to invasively measured hemodynamic diastolic indexes were assessed in 13 patients with isolated aortic stenosis (AS), and compared to Doppler indexes in 10 normal subjects matched for age, heart rate, left ventricular (LV) ejection fraction and LV load. Patients with AS showed no difference in Doppler early filling (E) indexes, but demonstrated greater Doppler atrial filling (A) indexes in comparison to normal subjects: atrial velocity (89 +/- 31 vs 56 +/- 7 cm/s), atrial integral (11.4 +/- 4.8 vs 5.7 +/- 1.6 cm), A/E velocity (1.69 +/- 0.89 vs 1.06 +/- 0.26) and A/E integral (3.53 +/- 6.64 vs 0.81 +/- 0.27) (all p less than 0.05). Doppler indexes in patients with AS did not correlate with hemodynamic indexes of LV relaxation or chamber stiffness. Significant correlations were observed between Doppler and angiographic peak filling rates (r = 0.70) and between Doppler atrial filling velocity and LV end-diastolic volume (r = -0.66), LV end-diastolic pressure (r = -0.48) and LV ejection fraction (r = 0.53) (all p less than 0.05). These data indicate that, compared to matched normal subjects, most patients with AS have an increased atrial contribution to LV filling. However, in patients with decreased LV function, atrial function may also be depressed, as indicated by a decreased atrial contribution to LV filling, resulting in "normalization" of the Doppler mitral flow pattern.  相似文献   

12.
Impaired diastolic function has been described in healthy elderly subjects. Pulmonary blood volume (PBV) changes with exercise have been associated with left ventricular dysfunction, but not directly related to diastolic abnormalities. Exercise-induced relative changes in PBV were measured using gated blood pool imaging with count density comparisons over the lung in 20 healthy volunteers: 13 elderly, age 76 +/- 5 years and seven young, age 27 +/- 4 years. Serial (first exercise stage, peak exercise, and post exercise) PBV ratios were measured and correlated to peak early filling rate, peak late filling rate, and percent atrial filling obtained from the resting left ventricular time-activity curve analysis. PBV ratios tended to be higher in elderly subjects, but reached significance only at the first stage of exercise (1.04 +/- 0.07 vs. 0.93 +/- 0.10, p less than 0.01). Significant correlations were found between PBV ratios at first exercise stage and peak early filling rate (r = -0.64), peak late filling rate (r = 0.47), and percent atrial filling (r = 0.48). A significant correlation was found between PBV changes at peak exercise and resting diastolic parameters. Exercise-induced PBV changes are associated with left ventricular diastolic dysfunction at rest. Diastolic abnormalities of the aged heart may explain the differential PBV response early into exercise between young and elderly healthy subjects.  相似文献   

13.
The role of Frank-Starling law of the heart in determining the increase in cardiac output during exercise in humans is still controversial (e.g., the mechanisms responsible for the enhancement of left ventricular [LV] filling during the shortened diastolic interval). Ten weight lifters, 12 swimmers and 12 sedentary subjects who underwent maximal upright bicycle exercise testing were studied. First-pass radionuclide angiography was performed both at rest and at peak exercise using a multicrystal gamma camera. Compared with resting values, heart rate and cardiac index at peak exercise increased by 101 +/- 16 beats/min (p less than 0.001) and 6.7 +/- 2.8 liters/min/m2 (p less than 0.001) in weight lifters, by 96 +/- 9 beats/min (p less than 0.001) and 9.5 +/- 2 liters/min/m2 (p less than 0.001) in swimmers, and by 103 +/- 9 beats/min (p less than 0.001) and 7.3 +/- 1.8 liters/min/m2 (p less than 0.001) in sedentary subjects. Stroke volume increased by 20.5 +/- 9.8 ml/m2 (p less than 0.001) in swimmers only. End-diastolic volume at peak exercise did not change in weight lifters and in swimmers; it decreased by 8.2 +/- 8.6 ml/m2 (p less than 0.01) in sedentary subjects. A significant correlation was found between the decrease in end-systolic volume and the increase in peak rapid filling rate at peak exercise in all 3 groups (r = 0.65, p less than 0.05 in weight lifters; r = 0.59, p less than 0.05 in swimmers; r = 0.67, p less than 0.05 in sedentary subjects.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

14.
Right ventricular diastolic function in systemic hypertension   总被引:4,自引:0,他引:4  
Right (RV) and left ventricular (LV) diastolic function was evaluated in 50 patients with mild, uncomplicated essential hypertension using pulsed-wave Doppler echocardiography. Patients with pulmonary, valvular or coronary artery disease were excluded and antihypertensive drugs were discontinued for the 2 weeks preceding the study. Ten normotensive patients without heart disease acted as control subjects. In the hypertensive patients, RV peak velocity of atrial filling was higher (42 +/- 10 vs 31 +/- 7 cm/s, p less than 0.01) and deceleration half-time was prolonged (96 +/- 20 vs 83 +/- 10 ms, difference not significant); ratio of early/atrial filling velocity (1.1 +/- 0.3 vs 1.7 +/- 0.4, p less than 0.001) and peak filling rate corrected to stroke volume (3.6 +/- 0.7 vs 5.3 +/- 0.9 SV/s, p less than 0.001) were lower. LV filling parameters showed similar changes. RV filling parameters did not correlate with age, LV mass or septal thickness but correlated weakly with LV radius/thickness ratio. There was good correlation between RV and the following corresponding LV filling parameters: peak filling rate, r = 0.68, p less than 0.001; ratio of early/atrial filling, r = 0.88, p less than 0.0001; and deceleration half-time, r = 0.62, p less than 0.001. Data indicate that RV diastolic function is abnormal in essential hypertension and these abnormalities are closely related to those of LV diastolic function.  相似文献   

15.
The relations of Metropolitan Life Insurance Co. Relative Weight values and blood pressure (BP) to minimal forearm vascular resistance, ventricular septal and posterior wall thickness, left ventricular (LV) mass index and cardiac diastolic function were assessed in 31 men, 37 +/- 2 (mean +/- standard error of the mean) years of age. Eighteen patients with untreated mild hypertension were compared with 13 normotensive control subjects of similar age and weight. The hypertensives had higher clinic (137 +/- 3/96 +/- 2 vs 121 +/- 4/81 +/- 3 mm Hg, p less than 0.001/less than 0.001) and home (p less than 0.001) BP. Despite higher BP, the hypertensives did not have significantly greater values than normotensives, respectively, for minimal forearm vascular resistance (2.20 +/- 0.12 vs 2.04 +/- 0.11 U), ventricular septal (9.9 +/- 0.5 vs 10.2 +/- 0.3 mm) and posterior wall thickness (10.2 +/- 0.4 vs 10.0 +/- 0.3 mm) or LV mass index (106 +/- 6 vs 107 +/- 6 g/m2). Furthermore, diastolic peak filling rate, an index of LV diastolic function, was virtually identical in the 2 groups (2.71 +/- 0.14 vs 2.69 +/- 0.07 liters/s, difference not significant). Correlates of peak filling rate included relative weight (r = -0.62, p less than 0.001), posterior wall thickness (r = -0.51, p less than 0.01) and age (r = -0.45, p less than 0.05). Relative weight also correlated significantly with posterior wall (r = 0.59, p less than 0.005), ventricular septal (r = 0.47, p less than 0.005) and LV mass index (r = 0.38, p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

16.
The purpose of this study was to characterize noninvasively left ventricular diastolic filling in patients with coronary artery disease (CAD), by the use of pulsed Dopplerecho. 139 consecutive patients with CAD (with myocardial infarction, MI, n = 110; without MI, n = 29) were included in the study and compared to 67 normal subjects. Analyzing age-matched subgroups, patients with CAD and MI showed a significantly lower peak early diastolic filling velocity (R) as compared to normal subjects. The ratio (E/L) of early (E) to late (L) filling velocity integral as well as the ratio of peak early (R) to peak late (A) filling velocity were significantly lower in patients with MI than in normal subjects. Furthermore, A was lower in patients with MI, as compared to patients without MI. There were no significant differences between patients with single-vessel and multi-vessel disease. The ejection fraction was not significantly related to the diastolic filling parameters. In the normal population (aged 15-66 years) all diastolic filling parameters tested showed a significant correlation with age. The best correlation was found with the E/L ratio (r = -0.63, p less than 0.001). In contrast, there was no significant correlation between age and any of the diastolic filling parameters in patients with CAD. In patients with MI and left ventricular enddiastolic pressure (LVEDP) greater than or equal to 20 mm Hg, E/L was within normal limits, however, and was higher than in patients with LVEDP less than or equal to 14 mm Hg (LVEDP greater than or equal to 20 mm Hg: 2.1 +/- 1.5 SD vs. LVEDP less than or equal to 14 mm Hg: 1.09 +/- 0.38 SD, p less than 0.003).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

17.
Left ventricular (LV) filling was examined by Doppler and M-mode echocardiography in 24 patients with LV hypertrophy (five with aortic stenosis, six with hypertrophic cardiomyopathy, and 13 with LV hypertrophy secondary to systemic hypertension) and in 18 normal subjects. Patients with LV hypertrophy had significantly lower Doppler-determined peak filling rates (218 +/- 17 vs 288 +/- 66 cc/sec, p less than 0.01), but M-mode determined peak rate of chamber enlargement and normalized peak rate of chamber enlargement did not differ significantly between groups. Doppler measures of the ratio between early and late filling were significantly depressed in patients with LV hypertrophy and correlated inversely with age in the normal subjects. The M-mode derived normalized peak rate of chamber enlargement and the Doppler-derived normalized peak filling rate correlated weakly, but significantly, when both groups were combined (r = 0.56, p less than 0.01). Thus Doppler measurements can detect abnormalities of LV filling in patients with LV hypertrophy. These abnormalities are present when M-mode filling indices and systolic function are still normal.  相似文献   

18.
Myocardial velocity gradient (MVG) derived from Doppler myocardial imaging and standard echocardiographic parameters were used to investigate whether age-related left ventricular (LV) functional and/or structural changes are different in long-term training athletes than in those leading a sedentary life style. Eighty-nine athletes (64 men, mean age 38 years, range 18 to 64) and 105 age-matched sedentary normal subjects were enrolled into the study. The MVG was analyzed in all patients throughout the cardiac cycle, and peak values were measured in systole and in diastole during both rapid ventricular filling and atrial contraction. No differences were found in LV systolic and late diastolic function between athletes and sedentary normal subjects. However, athletes had higher peak E waves in early diastole (73 +/- 10 cm/s vs 68 +/- 10 cm/s, p <0.001) and rapid ventricular filling MVG (10.2 +/- 1.5 s(-1) vs 7.2 +/- 2.8 s(-1), p <0.001) than sedentary normal subjects, suggesting a better early relaxation pattern. From LV diastolic indexes, the rapid ventricular filling MVG age-related decrease was less pronounced in athletes than in sedentary normal subjects (r = -0.39 vs r = -0.91; p <0.01). All other diastolic variables, including transmitral Doppler inflow, had a similar degree of age-related changes in both study groups. Thus, athletes, compared with those leading a sedentary lifestyle, have higher early diastolic performance, which is less affected by the physiologic aging process. It would appear that MVG derived from Doppler myocardial imaging may play an important role in the assessment of LV functional and/or structural changes.  相似文献   

19.
Using gated equilibrium radionuclide angiography, variables of diastolic filling were analyzed at rest and during supine bicycle exercise in normal subjects (Group 1, n = 18), coronary patients with normal resting ejection fractions (Group 2, n = 26), and coronary patients with reduced resting ejection fractions (Group 3, n = 8). Indexes analyzed were peak filling rate and filling fraction during the first third of diastole. At rest, the peak filling rate was significantly lower in coronary patients than in normal subjects (3.18 +/- 0.82 end-diastolic volume [EDV]/s in Group 1 versus 2.41 +/- 0.66 EDV/s in Group 2, p less than 0.005; and 1.34 +/- 0.26 EDV/s in Group 3, p less than 0.001 versus Group 1). These differences persisted at peak exercise. Coronary patients also had significantly lower filling fractions at rest and during exercise than did normal control subjects. The time from end-systole to peak filling rate was longer at rest in patients in Group 2 (203 +/- 52 ms) than in subjects in Group 1 (172 +/- 50 ms, p less than 0.025). This remained true when the time to peak filling was normalized by the R-R interval. Although the exercise time to peak filling was longer in coronary patients in both Groups 2 and 3 than in Group 1, these differences were not apparent when the interval was normalized by the R-R interval. Thus, abnormalities in peak filling rate and filling fraction exist in patients with coronary disease both at rest and during exercise, but large overlaps exist between normal and coronary patients. Caution is advised in comparing the timing of events during diastole because apparent group differences may be related in part to rest or exercise heart rate.  相似文献   

20.
A large atrial contribution to left ventricular (LV) filling (%A) in patients with LV hypertrophy has been assumed by some to indicate abnormal LV compliance. We tested this assumption by examining the influence of short- and long-term changes in load on compliance and filling dynamics using nitroprusside to decrease load in 11 patients with severe aortic stenosis (AS) and ergonovine to increase load in nine normal subjects. LV angiographic volume was analyzed frame-by-frame simultaneous with micromanometer pressure recordings. Operative LV chamber compliance (dV/VdP) and a time constant for isovolumic relaxation rate were computed using three-constant exponential equations fit to the data. Compared with normal subjects, resting left ventricular end-diastolic pressure was increased and dV/VdP was reduced in AS, but %A was not different. %A was inversely related to left ventricular end-diastolic pressure (r = -0.48, p = 0.02) and positively correlated with dV/VdP (r = 0.90, p less than 0.001) within the AS group. Nitroprusside infusion reduced LV peak systolic pressure by 11%, end-diastolic pressure by 38%, and end-diastolic volume by 12% (p less than or equal to 0.004 for each) and tended to increase dV/VdP by 26% (p = 0.23). These alterations in load resulted in a 21% decrease (-16 ml) in the early filling volume (p less than 0.05) and variable increases (mean, +7 ml; p = NS) in the late atrial filling volume and in the percent atrial contribution to ventricular filling (26 +/- 19% to 35 +/- 25% for the AS group, p = NS) that were related to changes in compliance.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

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