Pulsed Doppler Study Research Articles

Heart rate variability in hypertrophic obstructive cardiomyopathy: association with functional classification and left ventricular outflow gradients

Background: The aim of this study was to investigate cardiac autonomic control in patients with hypertrophic obstructive cardiomyopathy (HOCM) and to assess the indexes of heart rate variability (HRV) in relation to the clinical and echocardiographic features. Methods and results: Twenty-three patients (17 male, six female: mean age 43±11) with HOCM and 18 healthy volunteers were included. M-mode and two-dimensional echocardiography, pulsed and continuous-wave Doppler studies were obtained. All patients and volunteers underwent continuous 24-h ambulatory ECG monitoring. Time domain variables considered in this study were standard deviation of mean R–R intervals (SDNN), root mean-squared successive difference (RMSSD) and percentage of cycles differing from the preceding one by more than 50 ms (PNN 50%). Patients were compared to detect associations between indices of heart rate variability, left ventricular outflow tract obstruction and clinical status. Heart rate variability parameters were also correlated with the echocardiographic and clinical characteristics of the patients. Both New York Heart Association (NYHA) functional class I–II patients (group I) and NYHA III–IV patients (group II) had lower values of SDNN, RMSSD and PNN 50% when compared with the control group ( P<0.001, P<0.05 and P<0.01, respectively, for group I and P<0.001, P<0.001 and P<0.001, respectively, for group II). Time domain heart rate variability parameters were found to be significantly correlated with the subaortic dynamic obstruction. Conclusion: Heart rate variability is reduced in HOCM and well correlated with the degree of subaortic obstruction. Heart rate variability indices are also sensitive markers of the functional status.

Diagnóstico prenatal de vasa previa

ObjectivePrenatal diagnosis of vasa previa in cord insertion anomalies Material and methodWe examined six cases of cord insertion anomalies or placentation anomalies ResultsThree cases were diagnosed of vessels previous the presentation and near the internal cervical orifice. Two cases of twin pregnancy with a cord velamentous insertion of the second twin on the partition membrane, the situation of the insertions showed a clinical vasa previa of the second twin after the potential birth of the first twin. The last case showed an interplacental vascular septum, in a bilobed placenta, that was previous to the presentation and near the internal cervical orifice ConclusionThe bidimensional ultrasounds, the pulsed and color Doppler studies allowed the prenatal diagnosis of the vasa previa in the asymptomatic pregnancies. Its diagnosis was based in its suspect in cases with a velamentous insertion or with a bilobed placenta. In these situations, a detailed evaluation of the relation of the amniotic umbilical vessels with the inferior uterine segment or with the uterine region previous to the fetus will allow the diagnosis of the vasa previa

Doppler dynamics: their clinical significance and relationship with fetal blood gases and pH measurements

The aim of the study is to demonstrate the ability of abnormal Doppler indices to predict the acid-base status of the fetus. A pulsed Doppler study of umbilical artery, middle cerebral artery and thoracic aorta were assessed on 30 intrauterine growth restricted and 27 appropriate-for-gestational-age fetuses immediately before cordocentesis. All the fetuses with absent end diastolic velocity in the umbilical artery were found to be acidemic by cordocentesis. Thoracic aorta pulsatility index (PI) increased and middle cerebral artery PI decreased significantly with increased umbilical impedance ( r = 0·702, r = -0·340, respectively). Umbilical artery and thoracic aorta PI significantly increased, whereas middle cerebral artery PI decreased with a decrease in umbilical blood pH ( r = -0·760, r = -0·642, r = 0·292, respectively). Doppler findings have a very strong correlation with the acid-base status of the fetuses. Increased umbilical impedance is associated with progressive impairment of placental gas exchange and that by the time diastolic flow is lost hypoxaemia or acidaemia is usually present.

F48Vasoconstrictor effect of the proximal segment of the fetal middle cerebral artery after an external partial occlusion of the umbilical vein (vasoconstrictor reflex)

BackgroundWe studied the repercussion of the nuchal cords on the proximal segment of the middle cerebral artery (pMCA) (segment with a rich innervation).MethodWe performed an external partial occlusion of the umbilical vein (through maternal abdominal wall) during 1–2 s to stimulate the baroreflex (pressure test or PT). We performed 76 PT in 36 fetuses. The pMCA was studied sonographically before, during and after the PT through pulsed Doppler and color Doppler energy (CDE).ResultsDuring the PT we observed stop the whole of the umbilical vein flow while maintaining the flow of the umbilical arteries. We observe a vasoconstrictor effect on the pMCA using CDE. This effect reflected a moderate‐severe segmental stenosis in the pMCA, however, flow in the remaining MCA was maintained. Sometimes, the effect vasoconstrictor produced a reverse flow on the pMCA to pulsed Doppler study. Post occlusion a cerebral vasodilatation took place, although in occasions an increased vascular tone persisted. Some fetal movements also could produce a similar effect in the pMCA (spontaneous PT).ConclusionThe PT produces an effect vasoconstrictor in the pMCA. Variations of this reflex can be the origin of some perinatal motor injury of intrauterine origin.

Right ventricular diastolic filling assessed by conventional doppler and tissue Doppler imaging in normal children.

To examine age-related changes in right ventricular filling dynamics, we performed conventional pulsed Doppler (n=99) and tissue Doppler (n=30) echocardiographic studies in normal subjects aged 7 days to 273 months. The tricuspid flow velocity during early diastole (peak E) wave correlated significantly but weakly with the logarithm of age. The peak E wave in the early neonatal period was almost 80% of the older children's values and increased to 100% by 36 months of age. In the right ventricular tissue Doppler imaging, the peak myocardial velocity during early diastole also increased significantly with the logarithm of age. However, the tissue Doppler peak A did not change with age. There was a significant correlation between the tissue Doppler peak E wave and the tricuspid peak E wave and between the tissue Doppler peak E/A wave and the tricuspid peak E/A wave. The age-related changes in the tricuspid inflow velocity patterns were similar to the age-related alterations in the right ventricular myocardial velocity patterns. Age-related changes in the tricuspid inflow velocity and myocardial velocity patterns may be related to age-related maturation in the right ventricular diastolic performance.

Rationale of the cox maze procedure for atrial fibrillation during redo mitral valve operations

Objective: The frequency of reoperation for mitral valve diseases with chronic atrial fibrillation has increased steadily. This study examined the rationale for using the Cox maze operation for atrial fibrillation during redo mitral valve operations. Methods: Between June 1992 and July 1995, we performed the maze procedure in 42 patients as a concomitant operation with redo mitral valve surgery (maze group). Associated procedures were tricuspid valve surgery in 27 patients and aortic valve surgery in 15 patients. The mean age at operation was 57.3 ± 9.7 years, and the mean interval from the previous operation was 14.3 ± 10.5 years. The mean follow-up period after the maze procedure was 25.5 ± 10.8 months. Atrial fibrillation was present at the time of the previous operation in 29 patients (69%). Results: Neither hospital death nor late death occurred. Sinus rhythm was regained in 28 patients (67%), and an atrial A-wave was detected in 21 patients (50%) by pulsed Doppler study. Patients in whom sinus rhythm was restored had a shorter history of atrial fibrillation (9.0 ± 6.0 years vs 15.9 ± 4.6 years, p = 0.0009), a larger f-wave on lead V 1 of the electrocardiogram (0.18 ± 0.10 mV vs 0.10 ± 0.08 mV, p = 0.017), and a smaller cardiothoracic ratio (63% ± 8% vs 67% ± 5%, p = 0.049) than patients with persistent atrial fibrillation. During the same period, 54 patients underwent mitral valve reoperation without the maze procedure (control group). The aortic crossclamp and cardiopulmonary bypass times were slightly longer ( p = 0.048 and p = 0.012) in the maze group (133 ± 28 minutes and 221 ± 43 minutes) than in the control group (126 ± 65 minutes and 197 ± 78 minutes). There was no significant difference in the amount of chest tube drainage or transfusion between the two groups (890 ± 510 ml and 2120 ± 1600 ml, respectively, in the maze group and 840 ± 480 ml and 2140 ± 1760 ml, respectively, in the control group). It was not necessary to reopen the chest for bleeding significantly more often in one group than in the other (14% in the maze group and 7% in the control group), and it was possible to operate without transfusion with the same frequency in the two groups (17% in the maze group and 20% in the control group). Conclusion: These results suggest that the maze procedure should be considered in selected patients who have a high possibility of regaining sinus rhythm during redo mitral valve operations. (J T HORAC C ARDIOVASC S URG 1996;112:1216-22)

Severe pulmonary hypertension as a cause of reverse aortic arch flow in the neonate: Report of two cases

We describe two newborn infants with severe pulmonary hypertension and circulatory collapse. In both cases, pulsed and color flow Doppler studies showed systolic and diastolic reversal of flow in the transverse aortic arch to the level of the innominate artery. No associated cardiac or noncardiac anomalies could explain the reverse flow in the aortic arch. Severe pulmonary hypertension and low left ventricular output were thought to be responsible for the Doppler findings. Reversal of the aortic arch flow in the newborn with pulmonary hypertension may be associated with a poor prognosis, and early consideration of extracorporeal membrane oxygenation in such patients may be indicated.

Prenatal diagnosis of gastroesophageal reflux by color and pulsed Doppler ultrasonography in a case of congenital pyloric atresia

A case of pyloric atresia diagnosed in the third trimester is described. Real-time ultrasonographic examination revealed polyhydramnios, enlarged stomach, evident gastric peristalsis and esophageal dilatation. Color and pulsed Doppler studies of the gastroesophageal junction revealed the presence of a biphasic flow pattern that was consistent with gastroesophageal reflux.

Echocardiographic and cardiac doppler assessment of mice

Recent studies have suggested that intermediate-frequency M-Mode transthoracic echocardiographic imaging is a promising method for evaluating the left ventricle in transgenic mice. However, there is a paucity of data regarding two-dimensional (2-D) echocardiography and cardiac Doppler echocardiography in this model. Therefore we studied 15 mice (body weights 38 to 65 gm) with an ultrasound system equipped with a 9 MHz transducer. M-mode, 2-D, pulsed, and color-flow Doppler studies were performed. Mean +/- SD for septal, posterior wall, and left ventricular cavity dimensions at end diastole were the following: M-mode: 1.1 +/- 0.2, 1.0 +/- 0.2, and 3.7 +/- 0.7 mm; 2-D: 1.0 +/- 0.2, 1.1 +/- 0.3, and 3.0 +/- 0.6mm. Left ventricular fractional shortening was assessed from the M-mode echocardiogram: mean 53.7% +/- 10.7% (range 42% to 77%). 2-D assessment of left ventricular mass correlated better with left ventricular mass identified at necropsy than left ventricular mass identified by M-mode echocardiography (r = 0.70; p = 0.007 versus r = 0.07; p not significant). 2-D visualization of left ventricle, proximal aorta, and aortic and mitral valves was excellent and was obtained mainly from a "parasternal" window. Apical views were more difficult to obtain. Mean +/- SD for aortic peak and mean velocities and velocity-time integral were 0.53 +/- 0.13, 0.32 +/- 0.08, and 0.025 +/- 0.008 m/sec. Estimated stroke volume was 0.0506 +/- 0.018 ml/beat. Cardiac output was 12.64 +/- 7.87 ml/min. Mean +/- SD for mitral peak E, peak A, and E/A ratio were 0.45 +/- 0.09 m/sec, 0.19 +/- 0.06 m/sec, and 2.4 +/- 0.66 m/sec, respectively. In all mice the E/A ratio was greater than 1 (range 1.76 to 3.6). Color-flowing imaging clearly displayed normal mitral inflow and left ventricular outflow. In one mouse, aortic regurgitation was recorded by pulsed Doppler echocardiography. Echocardiographic, pulsed, and color-flow Doppler assessment of mice is feasible. In this study left ventricular mass was assessed better by 2-D measurement of left ventricular dimensions. Assessment of left ventricular performance is feasible. Color Doppler-guided evaluation of aortic flow and aortic root measurement permits assessment of stroke volume and cardiac output.

Increased Fetal Activity and Heart Rate During and Immediately After Pulsed Doppler Echocardiography

Introduction: Previous reports have suggested that the use of continuous‐wave Doppler for nonimaging heart rate monitoring or in utero Doppler imaging increased fetal activity. In this study, 11 fetuses (EGA 20–28 weeks) underwent a cardiac 2‐D ultrasound and pulsed Doppler examination (since pulsed Doppler is more often used for fetal cardiac diagnosis) with 2‐D and Doppler performed in a randomized order and with 10‐minute ultrasound observation periods with as little transducer movement as possible before, during, and after 2‐D only, and Doppler evaluation. Methods: All studies were performed with informed consent at the lowest available Doppler power &lt; 90 mW/cm2 spatial peak temporal average. Fetal heart rate, the number of fetal gross movements / min, and the percent time occupied by fetal movements were evaluated by two blinded observers from video taped records. Patients had been referred to rule out fetal heart disorders but all echoes showed normal cardiac anatomy. Results: Fetal heart rate after pulsed Doppler study was statistically higher by analysis of variance (mean 127 beats/min) than in the pre‐Doppler evaluation period (mean 120) and was highest during the Doppler exam period (mean 136; P &lt; 0.05) in 10 of 11 fetuses. The percent time of fetal movements was highest during the Doppler exam period and in 9 of 11 fetuses movement increased. The raw number of gross movements / min, however, was highest after the Doppler. No such changes occurred during or after 2‐D alone. Conclusion: Whether associated with slightly higher energy output, minimal thermal changes, or audible switching or electronic output sounds transmitted from the instrumentation through the uterus, fetal heart rate and activity increased in our study both during and after pulsed Doppler examination.

Effect of acute pericardial tamponade on the relative contributions of systolic and diastolic pulmonary venous return: A transesophageal pulsed Doppler study

The effect of acute pericardial tamponade on pulmonary venous return was assessed by transesophageal pulsed Doppler echocardiography. In 14 open-chest anesthetized dogs peak pulmonary venous flow velocities in systole (V J) and in diastole (V K) were measured during apnea and atrial pacing while acute tamponade was induced by intrapericardial instillation of 0.9% sodium chloride solution. Before intravascular volume expansion, induction of acute tamponade resulted in a significant decline in V K (43 ± 17 to 19 ± 8 cm/sec; p < 0.05) but no change in V J or the ratio V J V K . After intravascular volume expansion, induction of acute tamponade resulted in significant reductions in V J (43 ± 9 to 29 ± 10 cm/sec; p < 0.001) and V K (37 ± 19 to 15 ± 11 cm/sec; p < 0.001). The effect was disproportionately greater on V K, however, resulting in a significant increase in V J V K (1.51 ± 0.84 to 2.58 ± 1.41; p < 0.001). The disproportionate effect of acute tamponade on V K suggests that increased pericardial pressure directly constrains diastolic filling of the left atrium as a conduit to the left ventricle and that it does not decrease the systolic and diastolic phases of pulmonary venous return uniformly. Intravascular volume expansion increases cardiac output before acute tamponade, but during acute tamponade it amplifies the disproportionate impact of increased pericardial pressure on left ventricular diastolic filling as the left ventricle is constrained within the fluid-filled pericardial sac.

Effect of maternal cocaine abuse on renal arterial flow and urine output of the fetus

Our purpose was to study the short-term effect of maternal cocaine abuse on blood flow of the fetal kidney and the fetal hourly urine output. Thirty-three pregnant patients of various gestational ages with a history of cocaine abuse were studied. Patients were included if the urine specimen was positive for cocaine on the day of study. Patients were excluded if the urine specimen was positive for any other vasoactive substances or medications. Color and pulsed wave Doppler studies were used to obtain the flow velocity waveform of the fetal renal artery. The resistance index was calculated from systolic and diastolic values of flow velocity waveforms, Longitudinal, transverse, and anteroposterior diameters of the fetal urinary bladder were measured from transverse and coronal images at their maximum diameters, and the bladder volume was calculated. The hourly urine output of the fetus was measured from the difference in the bladder volume at half-hour intervals. As controls, 110 normal pregnancies between 19 and 40 weeks were similarly studied for normal values. The resistance index of the fetal renal artery and the hourly fetal urine output of the two groups were compared. The resistance index of the fetal renal artery of normal pregnancies had a negative association with gestational age (p < 0.05). Cocaine-exposed fetuses had a significantly higher resistance index of the renal artery (p < 0.01) than did normal fetuses of corresponding gestational ages. A decrease in the hourly urine output of cocaine-exposed fetuses was observed, compared with normal controls of corresponding gestational ages (p < 0.001). The resistance index values of fetal renal artery and fetal urine output were affected by maternal cocaine abuse.

Neonatal cerebral circulation in relation to neurosonography and neurological outcome: a pulsed Doppler study.

In the pathogenesis of neonatal intracranial pathology and adverse neurologic outcome, severe instability of the neonatal cerebral circulation might play an important role. To examine this hypothesis the relationship was explored between intracranial pathology as detected by neurosonography during the first week of life, changes in cerebral blood flow velocity (CBFV) as measured by Doppler ultrasound in the same period and neurologic outcome, as measured by standardized tests during the first year of life. A group of 128 infants born after a pregnancy duration between 25 2/7 and 32 6/7 weeks was studied. In 40% of the infants, the time of occurrence of both types of intracranial pathology was within 1 hour after birth. No relation could be demonstrated between this occurrence and CBFV. Also after the appearance of intracranial pathology no specific changes in CBFV were seen. CBFV was associated with neurological outcome at term age. However, CBFV did not predict outcome of neurological examination at 6 and 12 months of corrected age. Intracranial hemorrhages were associated with abnormal neurological outcome at all assessments. Ischemic lesions were only associated with adverse outcome at 12 months of age.

Transvaginal color and pulsed Doppler study of uterine blood flow in the first and early second trimesters of pregnancy: normal versus abnormal.

Transvaginal color Doppler ultrasonography was used to study 131 normal early pregnancies, 30 molar pregnancies, 20 threatened abortions, two blighted ova, and five pregnancies with intramural myoma. Four separate parts of the maternal circulation were studied: uterine, arcuate, radial, and spiral arteries. There was statistical difference in the RI and PI among uterine, arcuate, radial, and spiral arteries (P < 0.001) in all observed groups of patients except those with intramural myoma. When the same part of the maternal circulation was compared among different groups of patients, the following results reached statistical significance: uterine artery in normal and molar pregnancy (P < 0.001); arcuate artery in normal and molar pregnancy (P < 0.001); radial artery in normal and molar pregnancy (P < 0.001) and in normal pregnancy and threatened abortion (P < 0.01); spiral artery in normal and molar pregnancy (P < 0.001), in normal pregnancy and threatened abortion (P < 0.01), and in molar pregnancy and threatened abortion (P < 0.01). The standard values of blood flow are different in normal and in some cases of abnormal early pregnancy (molar pregnancy, threatened abortion).

Laser Doppler and microvascular pulsed Doppler studies of the physiology of venous flaps

Venous flaps based on inferior epigastric pedicle were raised in adult Wistar rats. Their haemodynamics were studied using laser Doppler on the skin and microvascular ultrasonic pulsed Doppler on the pedicle vein. The results of the study seem to indicate a to and fro flow in the single cephalad pedicle vein. A discussion regarding the physiology of venous flaps is presented.

Atrial septal defect after balloon mitral valvuloplasty: a transesophageal echocardiographic study.

Fifty patients with rheumatic mitral stenosis aged twelve to thirty-six (twenty +/- six) years were studied by two-dimensional, pulsed and color Doppler echocardiography during, seventy-two hours after, and biweekly for three months after balloon mitral valvuloplasty (BMV). Transesophageal echocardiography (TEE) done immediately after BMV (in the catheterization laboratory) detected a new atrial septal defect (ASD) in 46 (92%) patients. These measured 1 to 2 (mean 1.2 +/- 0.3) mm in diameter. Doppler color flow mapping guided the location of the ASD in most of the cases. A narrow jet of left-to-right shunt could be evaluated by pulsed Doppler studies. Velocity time integral (VTI) of the jet across one cardiac cycle and the diameter of the ASD were used to calculate the left-to-right shunt (shunt = VTI x pi (D/2)2 x heart rate). The estimated shunt was 0.04-0.39 (mean 0.20 +/- 0.10) L/minute. A repeat study at seventy-two hours revealed the defect in 40 (80%) patients. At three months, the defect persisted in only 5 (10%) cases. The mean interval of closure of ASD was 4.6 +/- 2.2 weeks. The authors conclude: (1) ASD occurs commonly after BMV, (2) the septal defect and the resultant left-to-right shunt are insignificant, and (3) ASD disappears in the majority of cases by three months after BMV.

Comparative effects of diabetes mellitus and hypertension on physical properties of human large arteries

Objectives. The effects of hypertension and diabetes on the physical properties of large arteries were compared in men.Background. Although these two diseases are linked to vascular stiffening, no study has analyzed whether the arterial rigidity in diabetes is as substantial as in hypertension.Methods. Noninvasive measurements of brachial artery mean pressure, diameter (pulsed Doppler study) and compliance (pulse wave velocity) were obtained in 29 men: 11 control subjects, 9 hypertensive nondiabetic patients and 9 diabetic normotensive patients. Individual diameter- and compliance-pressure curves extrapolated from the measured diameter and mean pressure point with a logarithmic elastic model permitted calculation of isobaric diameter and compliance at the same pressure in each subject.Results. Compared with control subjects, hypertensive patients had a larger brachial artery measured diameter and isobaric diameter (p < 0.01) and lower measured and isobaric compliance (p < 0.001, p < 0.01). Compared with control subjects, diabetic patients had lower measured and isobaric compliance (p < 0.01). Comparison of diabetic and hypertensive patients showed that measured diameter and isobaric diameter were decreased in the former (p < 0.01). In the control and hypertensive groups, mean pressure correlated positively with measured diameter and isobaric diameter (p < 0.01) and negatively with measured and isobaric compliance (p < 0.001 and p < 0.01, respectively). In the control and diabetic groups, fasting glucose correlated negatively with measured and isobaric compliance (p < 0.01, p < 0.05).Conclusions, Intrinsic alterations of the large artery independent of a stretching pressure effect reduce arterial elasticity similarly in those with hypertension or diabetes. The loss of compliance is related to the chronic elevation of blood pressure in hypertension and to that of glycemia in diabetes and is associated with a relative large artery vasoconstriction in diabetic patients as compared with patients with hypertension.

Influence of human chorionic gonadotrophin, oestradiol and progesterone on uteroplacental and corpus luteum blood flow in normal early pregnancy.

A transvaginal colour and pulsed Doppler study was performed on 44 women with normal pregnancies between 5 and 16 weeks of gestation. Maternal levels of human chorionic gonadotrophin (HCG), free alpha-HCG subunit, free beta-HCG subunit, 17 beta-oestradiol and progesterone were determined in sera obtained at the time of Doppler examination. Uterine peak systolic velocity (PSV) and alpha-HCG and 17 beta-oestradiol levels increased significantly (P < 0.001) from the second to the fourth month of gestation, whereas uterine and spiral resistance index (RI) decreased significantly (P < 0.005 and P < 0.001, respectively) with gestational age. Levels of HCG and beta-HCG peaked significantly (P < 0.01) during the third month of gestation. Corpus luteum PSV and RI and progesterone levels did not vary significantly with gestational age. Multiple regression analysis showed that gestational age was the only significant (P < 0.05) contributor to uterine PSV and spiral RI variability. In addition to gestational age, 17 beta-oestradiol had a significant (P < 0.001) influence on uterine RI. Both corpus luteum PSV and RI were significantly (P < 0.01 and P < 0.05, respectively) related to progesterone levels. Corpus luteum PSV was also significantly (P < 0.05) related to 17 beta-oestradiol levels and RI to HCG levels.(ABSTRACT TRUNCATED AT 250 WORDS)

Color Doppler imaging of the uterine artery in pregnancy: normal ranges of impedance to blood flow, mean velocity and volume of flow.

In a cross-sectional study of 215 healthy women with singleton pregnancies at 18-42 weeks' gestation, color Doppler imaging was used to identify the main uterine arteries for subsequent pulsed Doppler studies. Flow velocity waveforms were obtained and indices of impedance, mean blood velocity and vessel diameter were measured, and the total volume of blood flow to the uterus was calculated. Impedance to flow decreased, I whereas blood velocity and volume flow increased significantly with gestation. Furthermore, impedance to flow was lower and velocity higher in the placental uterine artery, i.e. closest to the main bulk of the placenta, than in the non-placental artery.

Aging and physical activity determine cardiac structure and function in the older athlete.

To evaluate the effects of age and physical activity on cardiac structure and function, 45 ultra-endurance athletes were compared with 24 sedentary control subjects. Two-dimensionally guided M-mode echocardiograms and pulsed Doppler studies of left ventricular inflow velocity were obtained. Both older and younger athletes differed from age-similar sedentary control subjects in having lower heart rates (56 vs. 72 beats/min, younger; 53 vs. 74 beats/min, older), larger left ventricular cavities at end diastole (5.4 vs. 4.9 cm younger; 5.4 vs. 4.9 cm older), and higher ratios of early to atrial inflow velocities (2.14 vs. 1.37, younger; 1.32 vs. 0.83, older; all P less than 0.05). Older athletes differed from younger athletes in having higher systolic and diastolic blood pressures (131/79 vs. 122/71 mmHg), greater posterior wall thickness (1.1 vs. 0.9 cm), lower rapid filling velocity (52 vs. 70 cm/s), higher atrial systolic velocity (41 vs. 34 cm/s), and lower early-to-atrial inflow velocity ratios (1.32 vs. 2.14, all P less than 0.05). Thus the aging heart manifests structural and functional changes in response to physical activity that are similar but not identical to those seen in younger subjects. The expected pattern of cardiac alterations normally seen in response to age is modified in the older athlete, suggesting that exercise training, as well as aging, is an effective stimulus in shaping left ventricular structure and function in the older heart.