Latent impairment of left ventricular filling in hypertension without left ventricular hypertrophy and improvement by dipyridamole treatment: pulsed Doppler echocardiography study

Left ventricular (LV) filling impairment in patients with hypertension (HT) not necessarily associated with LV hypertrophy has not been sufficiently investigated. Therefore, we examined the response of LV filling to isometric exercise in patients with HT without LV hypertrophy and LV filling abnormality at rest. We studied 25 patients (aged 40 to 66 years, mean 51 +/- 7 years) and 13 age-matched normal subjects. The HT patients were selected by the following criteria: 1) systolic blood pressure (sBP) over 160 mmHg and/or diastolic BP over 90 mmHg was observed at least three times during the last 6 months, 2) LV wall thickness was under 11 mm, and 3) the ratio of peak atrial LV inflow velocity (A) to peak early diastolic LV inflow velocity (E) was within the mean +/- SD of normal subjects. LV inflow was measured by pulsed Doppler flowmetry before and during handgrip exercise (50% maximal effort for one minute and a half) in the patients before [HT-D (-)] and after [HT-D (+)] dipyridamole (D) administration (0.28 mg/kg/4 min) and in the normal subjects (N). Doppler-derived indices were A, E, A/E, DR (the deceleration rate from peak to half of the early diastolic inflow velocity), % delta A/E (% change in A/E from baseline), and % delta DR (% change in DR from baseline). There was no significant difference in LV wall thickness between the HT and N groups. There was also no significant difference in A/E at rest between the three groups. Increase of sBP and heart rate were similar in all groups during handgrip exercise.(ABSTRACT TRUNCATED AT 250 WORDS)     

Analysis of left ventricular wall movement during isovolumic relaxation and its relation to coronary artery disease

Left ventricular angiograms of 60 patients with ischaemic heart disease and 10 normal subjects were digitized frame by frame in order to study abnormalities of wall movement during the period of isovolumic relaxation. Plots were made of regional wall movement around the cavity throughout the cardiac cycle. In normal subjects 1-5 to 3-0 mm of symmetrical outward wall movement occurred during isovolumic relaxation, associated with an apparent increase of left ventricular volume of 10 +/- 4 per cent. The corresponding peak velocities of wall movement were 4-3 to 5-7 cm/s, significantly less than those recorded in the same region of the cavity after mitral valve opening. In patients with ischaemic heart disease, the following abnormalities were encountered: (1) Abnormal inward movement, which, in single coronary artery disease, occurred in the area supplied by the affected vessel. (2) Abnormal outward movement of more than 6 mm in non-affected areas which appeared to be a compensatory phenomenon. (3) An abnormal cavity shape change towards a more circular configuration before mitral valve opening. (4) Reduced peak rates of wall movement in affected areas during systole and filling. It is concluded that such inward wall movement during isovolumic relaxation is abnormal and a sign of local ischaemia whose presence has significant effects on overall left ventricular function in both systole and diastole.     

The classification and analysis of the blood pathway in left ventricular cavity observed by left ventricular contrast echocardiography

We can observe and analyse the blood pathway in left ventricular cavity by contrast echocardiography using sonicated albumin, because it can be through the pulmonary capillaries. I. The observational classification of the blood pathway in left ventricular cavity. Group I: The contrast medium comes to the apex directly from the mitral orifice. Group II: The contrast medium comes to the apex along the posterior wall forming the spiral flow and turns back to the outflow tract. Group III: The contrast medium is found like a fireworks only at the apex. II. The factors associated with the blood pathway in left ventricular cavity. 1. Abnormality of left ventricular wall motion, 2. The form of left ventricular cavity, 3. Early diastolic peak velocity of the transmitral flow, 4. A/E, 5. Left ventricular function.     

Assessment of left ventricular volume by contrast echocardiography

Two-dimensional echocardiography for measuring left ventricular volumes usually gives volumes that are smaller than those determined with left ventriculography. This is due to less optimal image quality since manual tracing of endocardial borders requires still frames. Intravenous injection of echocontrast agent (Albunex) improve endocardial border recognition and therefore left ventricular volume measurements become more accurate. It is reported that contrast echocardiography significantly improves the correlation of echocardiographic left ventricular volume measurement with that of left ventriculography. From this points of view, contrast echocardiography is useful for the determination of left ventricular volumes in clinical settings.     

Detection of left ventricular aneurysms by cross-sectional echocardiography

Real-time cross-sectional echocardiographic studies of the left ventricle were performed in 31 consecutive patients with angiographically proven left ventricular aneurysms (group I). In each of these patients the presence and location of the aneurysm was visualized by the cross-sectional echocardiography. In four patients discrepancy in the extent of the aneurysm was noted due either to failure of the cross-sectional technique to visualize the entire anterior wall of the ventricle (3) or failure of the single plane angiogram to adequately define the lateral extent of the aneurysm (1). Ventricular shape and contraction sequence in patients with aneurysms were compared with similar patterns in 20 patients with normal left ventricles (group II), and 20 patients with ischemic heart disease and localized ventricular dysfunction without aneurysm formation (group III). Other noninvasive methods for detecting aneurysms (including physical examination, chest roentgenography, electrocardiography, and M-mode echocardiography) were also evaluated in the aneurysm group. This report suggests that cross-sectional echocardiography is a useful method for detecting ventricular aneurysms noninvasively.     

A new approach for evaluation of left ventricular diastolic function: spatial and temporal analysis of left ventricular filling flow propagation by color M-mode Doppler echocardiography

OBJECTIVES: To evaluate left ventricular diastolic function and differentiate the pseudonormalized transmitral flow pattern from the normal pattern, the propagation of left ventricular early filling flow was assessed quantitatively using color M-mode Doppler echocardiography. BACKGROUND: Because the propagation of left ventricular early filling flow is disturbed in the left ventricle with impaired relaxation, quantification of such alterations should provide useful indexes for the evaluation of left ventricular diastolic function. METHODS: Study subjects were classified into three groups according to the ratio of early to late transmitral flow velocity (E/A ratio) and left ventricular ejection fraction: 29 subjects with an ejection fraction > or = 60% (control group); 34 with an ejection fraction < 60% and E/A ratio < 1 (group I); and 25 with ejection fraction < 60% and E/A ratio > or = 1 (group II). The propagation of peak early filling flow was visualized by changing the first aliasing limit of the color Doppler signals. The rate of propagation of peak early filling flow velocity was defined as the distance/time ratio between two sampling points: the point of the maximal velocity around the mitral orifice and the point in the mid-left ventricle at which the velocity decreased to 70% of its initial value. High fidelity manometer-tipped measurement was performed in 40 randomly selected subjects. RESULTS: The rate of propagation decreased in groups I and II compared with that in the control group (33.8 +/- 13.8 [mean +/- SD] and 30.0 +/- 8.6 vs. 74.3 +/- 17.4 cm/s, p < 0.001, respectively) and correlated inversely with the time constant of left ventricular isovolumetric relaxation and the minimal first derivative of left ventricular pressure (peak negative dP/dt) (r = 0.82 and r = 0.72, respectively). CONCLUSIONS: Spatial and temporal analysis of filling flow propagation by color M-mode Doppler echocardiography was free of pseudonormalization and correlated well with the invasive variables of left ventricular relaxation.     

Evaluation of left atrial contribution to left ventricular filling in aortic stenosis by velocity-encoded cine MRI

Velocity-encoded cine MRI (VEC-MRI) can measure volume flow at specified site in the heart. This study used VEC-MRI to measure flow across the mitral valve to compare the contribution of atrial systole to left atrial filling in normal subjects and patients with left ventricular hypertrophy. The study population consisted of 12 normal subjects (mean age 34.5 years) and nine patients with various degrees of left ventricular hypertrophy resulting from aortic stenosis (mean age 70 years). VEC-MRI was performed in double-oblique planes through the heart to measure both the mitral inflow velocity pattern (E/A ratio) and the volumetric flow across the mitral valve. The left atrial contribution to left ventricular filling (AC%) was calculated. The results were compared with Doppler echocardiographic parameters. The VEC-MRI-derived mitral E/A ratios showed a significant linear correlation with E/A ratios calculated from Doppler echocardiography (r = 0.94), and the VEC-MRI-derived E/A ratios (2.1 +/- 0.5 vs 1.0 +/- 0.4) and AC% values (24.9 +/- 7.2 vs 45.7 +/- 16.4) were significantly different between normal subjects and patients with aortic stenosis (p < 0.01 in both groups). The same differences were seen in the Doppler echocardiographic parameters. The VEC-MRI-derived E/A ratio and AC% showed significant hyperbolic and linear correlations with left ventricular mass indexes (r = 0.95 and 0.86). In addition, the VEC-MRI-determined E/A ratio and the volumetric AC% displayed a highly significant hyperbolic correlation (r = 0.95). Thus VEC-MRI can be used to evaluate left ventricular diastolic filling characteristics in normal subjects and patients with abnormalities of diastolic filling.     

Relationship of the third heart sound to transmitral flow velocity deceleration

BACKGROUND: The third heart sound (S3) occurs shortly after the early (E-wave) peak of the transmitral diastolic Doppler velocity profile (DVP). It is thought to be due to cardiohemic vibrations powered by rapid deceleration of transmitral blood flow. Although the presence, timing, and clinical correlates of the S3 have been extensively characterized, derivation and validation of a causal, mathematical relation between transmitral flow velocity and the S3 are lacking. METHODS AND RESULTS: To characterize the kinematics and physiological mechanisms of S3 production, we modeled the cardiohemic system as a forced, damped, nonlinear harmonic oscillator. The forcing term used a closed-form mathematical expression for the deceleration portion of the DVP. We tested the hypothesis that our model's predictions for amplitude, timing, and frequency of S3 accurately predict the transthoracic phonocardiogram, using the simultaneously recorded transmitral Doppler E wave as input, in three subject groups: those with audible pathological S3, those with audible physiological S3, and those with inaudible S3. CONCLUSIONS: We found excellent agreement between model prediction and the observed data for all three subject groups. We conclude that, in the presence of a normal mitral valve, the kinematics of filling requires that all hearts have oscillations of the cardiohemic system during E-wave deceleration. However, the oscillations may not have high enough amplitude or frequency to be heard as an S3 unless there is sufficiently rapid fluid deceleration (of the Doppler E-wave contour) with sufficient cardiohemic coupling.     

Simultaneous measurement of pulmonary venous flow by intravascular catheter Doppler velocimetry and transesophageal Doppler echocardiography: relation to left atrial pressure and left atrial and left ventricular function

OBJECTIVES: The aim of our study was to compare measurements of pulmonary venous flow velocity obtained either by transesophageal Doppler echocardiography or by intravascular catheter Doppler velocimetry. Furthermore, the relation among pulmonary venous flow velocity, left atrial compliance and left atrial pressure was evaluated. BACKGROUND: Data about the relation between left atrial pressure and pulmonary venous flow velocity are controversial. METHODS: A total of 32 patients undergoing elective open heart surgery for coronary artery bypass grafting were included prospectively in the study. Pulmonary venous flow velocity (Doppler catheter) and left atrial pressure (microtip pressure transducer) were recorded simultaneously with recordings of pulmonary venous flow velocity obtained by transesophageal Doppler echocardiography. RESULTS: Agreement between Doppler catheter and Doppler echocardiographic measurements of pulmonary venous flow velocity (n = 18 patients) was analyzed using the Bland-Altmann technique. The 95% limits of agreement were -0.16 to +0.11 m/s for systolic peak velocity, -0.14 to +0.09 m/s for diastolic peak velocity and -0.12 to +0.10 m/s for atrial peak velocity. The closest agreement between both methods was found for the ratio of systolic to diastolic peak velocity, the ratio of systolic to diastolic flow duration and the time from Q deflection on the electrocardiogram to maximal flow velocity. Mean left atrial pressure was strongly correlated with the ratio of systolic to diastolic peak velocity (r = -0.829), systolic velocity-time integral (r = -0.653), time to maximal flow velocity (r = 0.844) and the ratio of systolic to diastolic flow duration (r = -0.556). The ratio of systolic to diastolic peak velocity and the time to maximal flow velocity were identified as strong independent predictors of mean left atrial pressure. Left atrial compliance was not found to be an independent predictor of mean left atrial pressure. CONCLUSIONS: Flow velocity in the left upper pulmonary vein can be reliably recorded by transesophageal pulsed wave Doppler echocardiography. Our data reveal further evidence that mean left atrial pressure can be estimated by the pattern of pulmonary venous flow velocity.     

Left ventricular systolic torsion and early diastolic filling by echocardiography in normal humans

This study describes a novel 2-dimensional echocardiographic technique to measure left ventricular (LV) systolic twist in humans and relates this measure to early ventricular filling. LV twist is the counterclockwise rotation of the left ventricle during systole when viewed from the apex. The effect of ventricular twist has been postulated to store potential energy, which ultimately aids in diastolic recoil, leading to ventricular suction. The generated negative early diastolic pressures may augment early ventricular filling. We measured ventricular twist in 40 patients with normal transthoracic echocardiograms. End-systolic twist was determined by measuring rotation of the anterolateral papillary muscle about the center of the ventricle. LV filling was assessed by analysis of transmitral Doppler flow velocities. The mean value obtained was 9 +/- 7 degrees of rotation. Twist measurements were highly reproducible with an intraobserver correlation coefficient of r = 0.881, p <0.001. The magnitude of ventricular twist was strongly correlated positively with acceleration of the mitral E-wave (r = 0.75; p <0.0001) and negatively with the mitral E-wave acceleration time (r = -0.83; p <0.0001).     

Mechanism of impaired left ventricular wall motion in the diabetic heart without coronary artery disease

OBJECTIVE: To elucidate whether impairment of the myocardial free fatty acid (FFA) metabolism and small vessel abnormalities in the myocardium are etiologic or contributory factors of myocardial dysfunction in patients with NIDDM without any significant coronary artery disease. RESEARCH DESIGN AND METHODS: We performed myocardial imaging with 123I-labeled beta-methyl-p-iodophenyl pentadecanoic acid (BMIPP), a branched analog of FFA, and dipyridamole-infusion 201thallium scintigraphy (Dip) in nine patients who demonstrated left ventricular wall motion abnormalities without any significant coronary artery disease and in fifteen control cases. As an index of myocardial FFA metabolism, the heart-to-mediastinum count ratio (H/M) of BMIPP was calculated from the mean count in the regions of interest at the heart and the upper mediastinum. RESULTS: Nine patients with reduced wall motion documented by left ventriculography (LVG), (hypokinetic group) demonstrated significantly lower BMIPP uptake (2.1 +/- 0.2, mean +/- SD) than fifteen patients with normal wall motion (normokinetic group) (2.3 +/- 0.2, P < 0.05). Regional ventricular wall motion observed by LVG, regional BMIPP uptake, and regional redistribution phenomenon (RD) were evaluated for five regions of the left ventricle: anterior, septal, apical, lateral, and inferoposterior regions. Wall motion was abnormal in 24 out of 120 regions. Regional BMIPP uptake was reduced in 47 regions. RD in Dip was observed in 23 regions. In regional analysis, the existence of defect in the BMIPP image showed significant correlation with wall motion abnormality (P < 0.01), but there was no significant relationship between the RD in Dip and regional wall motion abnormality (P = 0.16). Myocardial biopsy specimens obtained from the right ventricle of 20 patients showed no pathologic changes, with the exception of two patients. CONCLUSIONS: Our findings suggest that impairment of myocardial FFA metabolism rather than small vessel abnormalities in the myocardium is responsible for modest left ventricular dysfunction in patients with diabetes.     

Hemodynamic basis of mitral E transmission in the left ventricular cavity and its relation to the left ventricular relaxation process

Mitral E-wave transit time to the left ventricular outflow tract was measured as an E-Er interval in 30 subjects undergoing cardiac catheterization. The E-Er interval (range 30 to 190 ms) correlated with left ventricular peak negative dP/dt (r = -0.62, p = 0.0003) and tau (r = 0.74, p <0.0001) but not with left ventricular minimum, pre-A-wave, or end-diastolic pressures. We conclude that the E-Er interval is an easily obtainable Doppler measurement that reflects the left ventricular relaxation process.     

Relationship between atrial function, left ventricular isovolumic relation time, and early filling in dual chamber-paced patients

This investigation was performed to study atrial systolic function is response to modification of atrioventricular delay in a sample of 36 patients with a DDD pacemaker implanted for complete atrioventricular block. The relation between atrial systolic performance and diastolic-related parameters was also evaluated. Isovolumic relaxation time, early diastolic peak velocity, late (atrial) diastolic peak velocity, atrial filing fraction, and atrial ejection force were recorded at a pacing rate of 70 impulses/min and at atrioventricular delay of 200, 150, and 100 msec. Our data showed that the progressive shortening of atrioventricular delay induced a gradual increase in early peak velocity (median value 46 to 53 to 61.5 cm/sec, respectively, at 200, 150, and 100 msec intervals) and a gradual decrease in isovolumic relaxation time (median 92.6 to 81.5 to 69.7 msec at 200, 150, and 100 msec, respectively), atrial peak velocity (59 to 52 to 44.5 cm/sec at 200, 150, and 100 msec, respectively), atrial filling fraction (50.5% to 40% to 23.5% at 200, 150, and 100 msec, respectively), and atrial ejection force (17.2 to 14.7 to 8.5 kilodynes at 200, 150, and 100 msec, respectively). For every atrioventricular delay value detected, we found a significant correlation between isovolumic relaxation time and early peak velocity with atrial filling fraction and atrial ejection force. In addition, atrial ejection force was related directly to atrial filling fraction at studied atrioventricular delays. The two indexes of atrial systolic performance showed a parallel decrease by shortening the atrioventricular delay, and they can quantify atrial systolic performance equally in sequentially paced patients. Furthermore, our results are in accordance with the hypothesis that the interaction between the effectiveness of active left atrial emptying and isovolumetric relaxation time may play an important role in maintaining an ideal ventricular filling despite changes in atrial systolic function.     

Hemodynamic correlates of the third heart sound during the evolution of chronic heart failure

OBJECTIVES: The purpose of this study was to examine the temporal relation between the development of a third heart sound during the course of evolving heart failure and associated hemodynamic abnormalities. BACKGROUND: Although various theories have been proposed to explain the origin of the third heart sound, the exact origin of this sound remains unknown. METHODS: Studies were performed in seven dogs in which heart failure was produced by multiple sequential intracoronary micro-embolizations. Hemodynamic studies including ventriculography, pulsed wave Doppler echocardiography and intracardiac phonocardiography were performed at baseline, at the time at third heart sound was first heard and at 6 and 24 weeks after onset of the third heart sound. RESULTS: All dogs developed a third heart sound at 9 +/- 2 weeks after the initial embolization. The onset of the sound was accompanied by an increase in left ventricular chamber stiffness relative to the baseline value (0.25 +/- 0.03 vs. 0.14 +/- 0.01 mm Hg/ml) (p < 0.05) and mean deceleration of early mitral inflow velocity (1,040 +/- 90 vs. 590 +/- 40 cm/s per s) (p < 0.05). CONCLUSIONS: These data indicate that the onset of a third heart sound during the course of evolving heart failure occurs coincident with the development of increased left ventricular chamber stiffness and the manifestation of rapid deceleration of early mitral inflow velocity. These findings are consistent with a myocardial vibratory origin of this sound.     

Right ventricular diastolic disfunction and its relation to left ventricular performance in patients with hypertension

The potential effects of propofol emulsion (Diprivan) on the neuromuscular transmission and muscular contraction were studied using in vitro and in vivo nerve-muscle preparations of rats. The contractions of the isolated rat diaphragm elicited by either indirect or direct electrical stimulation were inhibited by propofol emulsion at threshold concentrations of 42 and 112 mumol l-1, respectively. Similarly, the gastrocnemius muscle contractions induced by either indirect or direct electrical stimulation in vivo were inhibited by propofol emulsion administration as a bolus injection of 2.5 mg kg-1 intravenously, followed by intravenous infusion of 150 micrograms kg-1 min-1 for 1 h into rats. The inhibitory effects of propofol in both preparations were greater with indirect rather than direct stimulation. Propofol emulsion was found to be capable of enhancing the paralysis of the indirectly stimulated rat diaphragm in vitro and gastrocnemius muscle in vivo induced by either pipecuronium or succinylcholine. The combination of propofol and pipecuronium led to a synergistic inhibition of the neuromuscular transmission, while the combination of propofol and succinylcholine led to additive inhibition. Pretreatment with propofol emulsion at these threshold concentrations markedly inhibited the stimulant effects of aminophylline and digoxin on the indirectly and directly induced diaphragmatic contractions. Also, the enhancement effects of aminophylline on the indirectly and directly and of digoxin on indirectly induced rat gastrocnemius muscle contractions were markedly inhibited by propofol emulsion administration to rats. Pretreatment with propofol emulsion at the threshold concentrations enhanced the inhibitory effects of verapamil on diaphragmatic contractions elicited either indirectly or directly and enhanced the inhibitory effect of adenosine on the contractions elicited indirectly. Similarly, the inhibitory effects of verapamil on the indirectly and directly and of adenosine on indirectly induced rat gastrocnemius muscle contractions were markedly potentiated by propofol emulsion administration to rats. In addition, doubling the concentration of calcium in the bathing fluid produced no change in the inhibitory effects of propofol emulsion on either indirectly or directly elicited diaphragmatic contractions, while doubling the concentration of external magnesium potentiated the propofol effects. Pretreatment with 4-aminopyridine suppressed the inhibitory effects of propofol emulsion on diaphragmatic contractions elicited either indirectly or directly. These results suggest that propofol acts presynaptically to inhibit the neuromuscular transmission and acts at the muscle membrane to inhibit the muscular contraction.     

Echocardiographic Doppler study of left ventricular filling in the diagnosis of minimal or moderate rejection in cardiac transplantation

The study of left ventricular filling by Doppler echocardiography may be a non-invasive diagnostic method of detection of acute rejection of cardiac transplants. The aim of this study was to assess the value of the method for diagnosis of minimal to moderate rejection (grades 1 to 3 of the Billingham classification). A total of 466 Doppler echocardiographic studies were performed in 23 cardiac transplantation patients (21 men, mean age 49.3 +/- 10 years) with endomyocardial biopsy as the reference method for the diagnosis of rejection. Over a follow-up period of 18.5 +/- 10 months, 22.7% of biopsies showed minimal or moderate rejection. The Doppler measurements of the isovolumic relaxation period and peak early diastolic (E) velocity with respect to the mitral velocity-time integral were no different in cases of acute rejection. The only difference observed was in the mitral half-pressure time which was much shorter in cases of rejection. However, after drawing a ROC graph, the accuracy of this parameter was insufficient for diagnosing rejection irrespective of the threshold of variation considered (23% sensitivity for a 20% shortening and 36% sensitivity for a 10% shortening). The authors conclude that Doppler echocardiographic study of left ventricular filling is of limited value for the diagnosis of acute minimal or moderate rejection in cardiac transplant patients. The half-pressure time may be a useful complement to endomyocardial biopsy or when biopsy investigations are performed less frequently.     

Abnormal left ventricular filling after neonatal repair of congenital heart disease: association with increased mortality and morbidity

BACKGROUND: The presence of mid-diastolic flow reversal on the mitral valve Doppler inflow indicates abnormal left ventricular filling. To determine whether mid-diastolic flow reversal predicts outcome in patients undergoing repair or palliation of neonatal congenital heart disease, we reviewed the echocardiograms and medical records of 40 patients with either left ventricular outflow obstruction or transposition of the great arteries. METHODS: All patients underwent surgical repair; transposition of the great arteries (TGA) = 17, coarctation of the aorta (CoA) = 14, interrupted aortic arch (IAA) = 8, and aortic stenosis (AS) = 1. The presence of mid-diastolic flow reversal was determined by pulsed Doppler interrogation of the mitral valve on preoperative and postoperative echocardiograms. RESULTS: Preoperative echocardiograms showed diastolic flow reversal in only 5 patients; 1 of 1 with AS and 4 of 14 with CoA. Twenty-one of 40 patients showed postoperative diastolic flow reversal; 1 of 1 with AS, 8 of 8 with IAA, 1 of 14 with CoA, and 11 of 17 with TGA. Postoperative mid-diastolic flow reversal 1 to 3 days after surgery was associated with higher mortality rate: 7 of 21 patients with diastolic flow reversal and 0 of 19 without diastolic flow reversal died. Patients with diastolic flow reversal who survived had longer intensive care unit (26.2 +/- 13.5 days vs 7.1 +/- 4.1 days, P <.001) and hospital (57.4 +/- 38.8 days vs 14.8 +/- 5.2 days, P <.05) stays. CONCLUSION: Mid-diastolic flow reversal is an indicator of prolonged hospital stay and mortality in patients with left ventricular outflow tract obstruction or TGA.