Diastolic dysfunction and diabetic cardiomyopathy: evaluation by Doppler echocardiography.

Doppler echocardiography has largely contributed to show the existence of a distinct diabetic cardiomyopathy. Several studies have pointed out the evidence of left ventricular (LV) remodeling and hypertrophy in alterations of both midwall systolic mechanics and LV diastolic filling in diabetes mellitus (DM), independent of the coexistence of concomitant risk factors. Further progress will be provided by new ultrasound technologies in this clinical setting. The combination of pulsed tissue Doppler study of mitral annulus with transmitral inflow may be clinically valuable for obtaining information about left ventricular filling pressure (LVFP) and unmasking Doppler inflow pseudonormal pattern, a hinge point for the progression toward advanced heart failure. In the absence of epicardial coronary artery stenosis, the ultrasound assessment of coronary flow reserve (CFR) may identify the dysfunction of coronary microcirculation, in relation with glycemic levels, insulin resistance, sympathetic overdrive, endothelial dysfunction, abnormalities of the angiotensin-renin system, and LV remodeling/hypertrophy. Diastolic dysfunction and impairment of CFR may be associated in DM, with a likely common origin. In this view, a comprehensive transthoracic Doppler evaluation of diabetic patients should include the assessment of diastolic function and estimation of LVFP by tissue Doppler, and coronary microvascular function by CFR test. Additional analysis of regional wall motion during a stress test would be required in patients with suspected coronary artery disease, another cause of diastolic dysfunction.     

Diastolic abnormalities in young asymptomatic diabetic patients assessed by pulsed Doppler echocardiography

Indexes of left ventricular diastolic filling were measured by pulsed Doppler echocardiography in 21 insulin-dependent diabetic patients and 21 control subjects without clinical evidence of heart disease. No patient had chest pain or electrocardiographic changes during exercise testing. The mean age of patients was 32 years. All patients had a normal ejection fraction. Six (29%) of the 21 diabetic patients had evidence of diastolic dysfunction as assessed by the presence of at least two abnormal variables of mitral inflow velocity. The ratio of peak early to peak late (atrial) filling velocity was significantly decreased in diabetic compared with control subjects (1.24 +/- 0.21 versus 1.66 +/- 0.30, p. less than 0.001). Atrial filling velocity was significantly increased in diabetic patients (74.3 +/- 16.7 versus 60.3 +/- 12.2 cm/s, p less than 0.004), whereas early filling velocity was reduced by a nearly significant degree (88.8 +/- 12.6 versus 98.5 +/- 18.8 cm/s, p less than 0.057). The atrial contribution to stroke volume as assessed by area under the late diastolic filling envelope compared to total diastolic area was also significantly increased in diabetic compared with control subjects (35 versus 27%, p less than 0.001). Left ventricular diastolic filling abnormalities in diabetic patients did not correlate with duration of diabetes, retinopathy, nephropathy or peripheral neuropathy. These data suggest that approximately one-third of such patients have subclinical myocardial dysfunction unrelated to accelerated atherosclerosis. Doppler echocardiography may offer a reliable noninvasive means to assess diastolic function and to follow up diabetic patients serially for any deterioration in cardiac status before the appearance of clinical symptoms.     

Diastolic dysfunction characterizes cirrhotic cardiomyopathy

Aim

Present study aims to study the occurrence of cirrhotic cardiomyopathy and its correlation to hepatorenal syndrome by assessing the cardiac status in patients with cirrhosis of liver and healthy controls.

Methods

Thirty alcoholic cirrhotic, thirty non-alcoholic cirrhotic and thirty controls were enrolled for the study. Cardiac parameters were assessed by color doppler echocardiography. Patients were followed up for twelve months period for development of hepatorenal syndrome.

Results

Mild diastolic dysfunction was present in 18 cirrhotic patients (30%): grade I in fifteen patients and grade II in three. Diastolic dysfunction was unrelated to age; sex and etiology of cirrhosis. Among all the echocardiographic parameters, only deceleration time was found to be statistically significant. Echocardiographic parameters in systolic and diastolic function were not different in compensated vs decompensated patients in different Child-Pugh classes or cirrhosis aetiologies.At one year follow-up, no significant differences were found in survival between patients with or without diastolic dysfunction. Hepatorenal syndrome developed in only two patients and its correlation with diastolic dysfunction was not statistically significant.

Conclusions

Present study shows that although diastolic dysfunction is a frequent event in cirrhosis, it is usually of mild degree and does not correlate with severity of liver dysfunction. There are no significant differences in echocardiographic parameters between alcoholic and non-alcoholic cirrhosis. HRS is not correlated to diastolic dysfunction in cirrhotic patients. There is no difference in survival at one year between patients with or without diastolic dysfunction. Diastolic dysfunction in cirrhosis is unrelated to circulatory dysfunction, ascites and HRS.     

Diastolic ventricular function in type 1 diabetic patients: a study using Doppler echocardiography.

The transmitral flow velocity pattern of 28 Type 1 diabetic patients and 39 age-matched healthy control subjects was studied for determination of left ventricular diastolic function. No patient had systemic hypertension, congestive heart failure, or ischaemic heart disease by clinical or electrocardiographic criteria. Echocardiographic measures of systolic ventricular function were within normal range in all subjects. The ratio of early to late transmitral peak flow velocity (ve/va) was significantly decreased in the diabetic patients (1.3 +/- 0.1 (+/- SE) vs 1.6 +/- 0.1, p less than 0.05), while other Doppler derived variables did not show any significant difference. No correlation of ve/va with duration of diabetes was found (r = -0.27), but it correlated with age in both groups (both r = -0.40, p less than 0.05). Furthermore, a significant correlation was found between ve/va and heart rate (r = -0.55 for diabetic patients, p less than 0.01; r = -0.58 for control subjects, p less than 0.01). After matching for heart rate (24 diabetic patients and 24 control subjects) no significant decrease of ve/va was observed in the diabetic group.     

Noninvasive evaluation of cardiac dysfunction by echocardiography in streptozotocin-induced diabetic rats

BACKGROUND: There has not been a noninvasive in vivo longitudinal evaluation of cardiac function in diabetic rats. The objective of this study is to examine the time course of development of cardiac dysfunction in streptozotocin (STZ)-induced diabetic rats. METHODS AND RESULTS: Cardiac function was evaluated by M-mode and Doppler echocardiography in anesthetized Wistar rats at 2, 4, 5, 6, and 8 weeks after injection with 65 mg of STZ/kg and in age-matched control rats before and after the administration of isoproterenol. Body weight (BW) was significantly less and blood glucose level significantly greater in diabetic rats compared with controls at 2 weeks and remained at these levels at all time points. The calculated left ventricular (LV) mass appeared slightly decreased in diabetic rats. However, LV mass-BW ratios were similar in controls and diabetic rats at 2, 4, and 5 weeks, but were significantly greater in diabetic rats at 6 and 8 weeks. Basal heart rate (HR) was significantly lower in diabetic rats at all time points studied. Basal LV systolic and diastolic dimensions, fractional shortening (FS), velocity of circumferential shortening (Vcf), peak emptying rate (PER), peak filling rate (PFR), and aortic peak velocity (APV) were not significantly different between controls and diabetic rats at 2 and 4 weeks. PER and PFR were significantly less in 5-week diabetic rats. However, Vcf, PER, and PFR were significantly less and FS and APV were similar at 6 and 8 weeks. Administration of isoproterenol increased HR, Vcf, FS, PFR, and PER in controls at all time points, but the increases in diabetic rats at 5, 6, and 8 weeks were less compared with those in controls. The increase in APV was significantly less in diabetic rats at all time points studied. CONCLUSION: STZ-induced diabetic rats showed bradycardia before contractile dysfunction. Overt and covert contractile dysfunction unmasked by isoproterenol begins at 5 weeks of diabetes. The overt LV systolic and diastolic dysfunction are fully manifested after 6 weeks of diabetes.     

Aortic regurgitation: evaluation by pulsed Doppler echocardiography

Ninety-one consecutive patients with aortic regurgitation, either isolated (23 subjects) or associated with other valvular diseases (68 subjects), were studied with pulsed Doppler echocardiography and subsequent aortography, and the results were compared in order to assess the value of the noninvasive technique for a semiquantitative evaluation of the degree of the aortic regurgitation. Both the noninvasive and invasive estimations were graded on a four-point scale. In the long-axis parasternal view, the outflow tract of the left ventricle was divided in four areas going from the aortic valve to the apex. Echo-Doppler grading (from + 1 to +4) was obtained by assessing the area where the abnormal diastolic flow could still be recorded. In the group as a whole, concordant degrees of the aortic insufficiency were obtained in 73 of 91 patients (r = .93; p less than .001); the degree of the aortic regurgitation was overestimated in 8 cases (9%) and underestimated in 10 cases (11%). Most of the discrepancies between the Doppler and the aortographic evaluation were found in patients with intermediate degree (+2, +3) of aortic regurgitation; the degree of discordance was never more than +1 or -1. Correlation between Doppler and aortography was higher in the subjects with pure aortic regurgitation (r = .94, p less than .001) and lower in the subgroup of the subjects with associated mitral stenosis (r = .87, p less than .001). Two-dimensional pulsed Doppler echocardiography is a simple and little time consuming technique that in selected groups of patients can be relied upon for the semiquantitated evaluation of the degree of aortic regurgitation.     

Diastolic heart failure can be diagnosed by comprehensive two-dimensional and Doppler echocardiography

There are many myocardial and non-myocardial conditions that cause heart failure with normal left ventricular ejection fraction (LVEF). Among them, diastolic heart failure (heart failure due to diastolic dysfunction) is the most common cause of heart failure with normal LVEF. Diastolic heart failure easily can be diagnosed by comprehensive two-dimensional and Doppler echocardiography, which can demonstrate abnormal myocardial relaxation, decreased compliance, and increased filling pressure in the setting of normal LV dimensions and preserved LVEF. Therefore, diastolic heart failure should always be considered when LVEF is normal on two-dimensional echocardiography in patients with clinical evidence of heart failure. The diagnosis can be confirmed if Doppler echocardiography and myocardial tissue imaging provide evidence for impaired myocardial relaxation (i.e., decreased longitudinal velocity of the mitral annulus during early diastole and decreased propagation velocity mitral inflow), decreased compliance (shortened mitral A-wave duration and mitral deceleration time), and increased filling pressure (shortened isovolumic relaxation time and an increased ratio between early diastolic mitral and mitral annular velocities). Early identification of diastolic dysfunction in asymptomatic patients by the use of echocardiography may provide an opportunity to manage the underlying etiology to prevent progression to diastolic heart failure.     

Differentiation of constrictive pericarditis and restrictive cardiomyopathy by Doppler echocardiography

Doppler ultrasound recordings of mitral, tricuspid, aortic, and pulmonary flow velocities, and their variation with respiration, were recorded in 12 patients with a restrictive cardiomyopathy and seven patients with constrictive pericarditis. Twenty healthy adults served as controls. The patients with constrictive pericarditis showed marked changes in left ventricular isovolumic relaxation time and in early mitral and tricuspid flow velocities at the onset of inspiration and expiration. These changes disappeared after pericardiectomy and were not seen in patients with restrictive cardiomyopathy or in normal subjects. The deceleration time of early mitral and tricuspid flow velocity was shorter than normal in both groups, indicating an early cessation of ventricular filling, but only patients with restrictive cardiomyopathy showed a further shortening of the tricuspid deceleration time with inspiration. Diastolic mitral and tricuspid regurgitation was also more common in the patients with restrictive cardiomyopathy. These results suggest that patients with constrictive pericarditis and restrictive cardiomyopathy can be differentiated by comparing respiratory changes in transvalvular flow velocities. In addition, although baseline hemodynamics in the two groups were similar, characteristic changes were seen with respiration that suggest differentiation of these disease states may also be possible from hemodynamic data.     

Diastolic forward blood flow in the pulmonary artery detected by Doppler echocardiography

The etiology of diastolic motion of the pulmonary valve seen on the M-mode echocardiogram has been the subject of much debate. To further investigate diastolic events in the pulmonary artery, the patterns of diastolic pulmonary artery blood flow velocity were studied using pulsed Doppler echocardiography in patients with a normal heart. Two diastolic waveforms were found, one in early diastole related to passive filling of the right ventricle and one in late diastole related to atrial contraction. These waveforms were also related to the two recognized phases of diastolic pulmonary valve motion detected by M-mode echocardiography. The presence of biphasic diastolic blood flow in the pulmonary artery was confirmed by electromagnetic flow velocimetry in four additional patients with various cardiac diseases and normal right heart pressures. It is concluded that both atrial contraction and passive right ventricular filling produce blood flow in the pulmonary artery.     

Diastolic heart failure can be diagnosed by comprehensive two-dimensional and Doppler echocardiography.

There are many myocardial and non-myocardial conditions that cause heart failure with normal left ventricular ejection fraction (LVEF). Among them, diastolic heart failure (heart failure due to diastolic dysfunction) is the most common cause of heart failure with normal LVEF. Diastolic heart failure easily can be diagnosed by comprehensive two-dimensional and Doppler echocardiography, which can demonstrate abnormal myocardial relaxation, decreased compliance, and increased filling pressure in the setting of normal LV dimensions and preserved LVEF. Therefore, diastolic heart failure should always be considered when LVEF is normal on two-dimensional echocardiography in patients with clinical evidence of heart failure. The diagnosis can be confirmed if Doppler echocardiography and myocardial tissue imaging provide evidence for impaired myocardial relaxation (i.e., decreased longitudinal velocity of the mitral annulus during early diastole and decreased propagation velocity mitral inflow), decreased compliance (shortened mitral A-wave duration and mitral deceleration time), and increased filling pressure (shortened isovolumic relaxation time and an increased ratio between early diastolic mitral and mitral annular velocities). Early identification of diastolic dysfunction in asymptomatic patients by the use of echocardiography may provide an opportunity to manage the underlying etiology to prevent progression to diastolic heart failure.     

Diastolic pulmonary forward flow associated with pulmonary regurgitation demonstrated by Doppler echocardiography

To demonstrate diastolic pulmonary forward flow, pulsed and continuous wave Doppler echocardiograms were recorded in four patients with postoperative residual pulmonary stenosis and regurgitation (Group I). To clarify the mechanism, we further examined 24 patients with pulmonary regurgitation without diastolic pulmonary forward flow, including three patients with surgical correction of tetralogy of Fallot (Group IIa) and 21 patients with functional pulmonary regurgitation (Group IIb), and compared the peak velocity and pressure half time of pulmonary regurgitation among the three groups. Diastolic pulmonary forward flow was characterized as a flow signal which began after the abrupt cessation of pulmonary regurgitation and continued until the beginning of ejection flow. The onset of the flow coincided with that of premature opening of the pulmonary valve, and was following atrial contraction in one, before atrial contraction in two, and mid-diastolic in one. The velocity of diastolic pulmonary forward flow was increased during inspiration and its maximum velocity was 1.3 m/sec. Simultaneous recording of pressures and continuous wave Doppler echo performed in two patients in Group I showed the equalization of right ventricular and pulmonary artery pressures during the flow. There was no significant difference in the peak velocity of pulmonary regurgitation among the three groups of patients. The mean pressure half time was significantly shortened in patients in Group I (90 +/- 11 msec) compared with those in patients in Group IIa (143 +/- 40 msec, p less than 0.05) and Group IIb (310 +/- 71 msec, p less than 0.001). In conclusion, a diastolic pulmonary forward flow seems to be produced by the rapid equalization of right ventricular and pulmonary artery pressures due to severe pulmonary regurgitation in the face of decreased right ventricular compliance.     

Dynamic subaortic obstruction in hypertrophic cardiomyopathy: analysis by pulsed Doppler echocardiography

To determine whether true obstruction to left ventricular ejection exists in patients with hypertrophic cardiomyopathy and a subaortic gradient, pulsed Doppler echocardiography was used to analyze the patterns of left ventricular emptying in 50 patients with hypertrophic cardiomyopathy (20 with and 30 without evidence of obstruction) and in 20 normal subjects. In obstructive hypertrophic cardiomyopathy, left ventricular ejection was characterized by early and rapid emptying (76 +/- 14% of aortic flow velocity in the initial one-third of systole). The proportion of forward flow velocity occurring before initial mitral-septal contact (and hence, by inference before the onset of the subaortic gradient) was variable, but averaged 58%. In contrast, the proportion of forward flow velocity occurring after mitral-septal contact (and, therefore, concomitant with the gradient and increased intraventricular pressure) was considerable, averaging over 40%. Mid-systolic impedance to left ventricular outflow was suggested by the rapid deceleration in aortic flow velocity concomitant with mitral-septal contact and premature partial aortic valve closure. Furthermore, left ventricular ejection was prolonged (384 +/- 40 ms) and the ventricle continued to empty and shorten during the period when both the pressure gradient and markedly increased intraventricular pressures were present. In 16 of 20 patients, a relatively small second peak in flow velocity appeared in late systole. Since marked systolic anterior motion of the mitral valve was still present, the late systolic portion of forward flow velocity also appeared to be largely ejected during imposition of a mechanical impediment to outflow. In contrast, patients with nonobstructive hypertrophic cardiomyopathy showed no evidence of impedance to left ventricular ejection. Aortic flow velocity waveforms were similar to those of normal subjects, with flow persisting to aortic valve closure; significant mitral systolic anterior motion and partial mid-systolic aortic valve closure were absent, and the systolic ejection period was normal (303 +/- 27 ms).(ABSTRACT TRUNCATED AT 400 WORDS)     

Diagnosis of constrictive pericarditis and restrictive cardiomyopathy by pulsed Doppler echocardiography

Characteristics of flow through atrioventricular valves were analyzed by pulsed Doppler echocardiography (PDE) in 7 patients with either constrictive pericarditis or restrictive cardiomyopathy and 10 controls to determine the value of this technique in their differentiation. All patients were admitted with systemic venous congestion and underwent right and left heart catheterization. PDE variables considered included peak flow velocity (PV), acceleration time, peak velocity of the atrial component (PVA), PVA/PV quotient, duration of early diastolic fillings, deceleration of early diastolic filling, duration of diastolic flow and mean temporal velocity. Ventricular filling differed between patients and controls in that the former group was characterized by higher PV's, lower PVA's, higher deceleration and lower PVA/PV quotient. When we compared both patient groups we found a significant tendency toward higher PV's, faster deceleration and lower PVA/PV quotient in constrictive pericarditis.     

Hypertrophic cardiomyopathy. Data from Doppler echocardiography

Hypertrophic cardiomyopathy (HCM) often involves the interventricular septum in the absence of any other cardiac or systemic abnormality capable of explaining this hypertrophy. M mode echocardiography shows septal hypertrophy and a posterior left ventricular wall of normal thickness. Two-dimensional echocardiography gives a better idea of the spatial distribution of the hypertrophy, especially in the short axis parasternal views. Obstruction to left ventricular ejection is another feature of this condition but presence of the obstruction remains a subject of controversy. Doppler studies give easy access to the changes in intraventricular hemodynamics and thereby contribute to fueling the controversy between supporters of intraventricular obstruction and those who prone the theory of hypercontractility. Color coded Doppler enables visualisation of the acceleration of blood flow in the left ventricular outflow tract and the demonstration of mitral regurgitation, which is always present in HCM with obstruction. The echocardiographic evaluation has been facilitated by the recent introduction of transesophageal probes. Doppler studies of mitral blood flow also enable evaluation of left ventricular diastolic function. The evaluation of left ventricular relaxation is often difficult and inaccurate in patients with supraventricular arrhythmias, intraventricular conduction defects or mitral regurgitation. Nevertheless, Doppler echocardiography remains the most reliable and useful method of evaluating HCM.     

Doppler echocardiography in prosthetic valve dysfunction

Summary We performed a retrospective study of 20 cases of prosthetic valve dysfunction which required reoperation and in which preoperative Doppler studies were performed. There were 13 mitral (3 mechanical, 10 bioprostheses) 5 aortic (1 mechanical and 4 bioprostheses), 1 pulmonary bioprosthesis and 1 mechanical tricuspid valve dysfunction. The aim of the study was to establish the diagnostic value of the Doppler examination by comparing the results with the operative findings. The parameters measured were: peak pressure gradient and mean pressure gradients in all prostheses, together with pressure half times and functional surface area in mitral and tricuspid valve prostheses. Cardiac catheterisation was performed in 6 cases before surgery. The diagnosis of prosthetic valve obstruction was correctly made, even in the 1 case with moderate stenosis. All cases of regurgitation were diagnosed and the topographical location of the leak was identified, except in 1 mechanical mitral valve prosthesis in which the regurgitant jet was detected only by continuous wave Doppler. Fourteen of the 20 cases were reoperated upon without catheterisation. These results suggest that Doppler echocardiography is a sensitive and specific diagnostic method of assessing prosthetic valve dysfunction. However, as the Doppler parameters are variable from one prosthesis to another, it is important to perform pulsed and continuous wave Doppler baseline studies in the immediate postoperative period as a reference in case of suspected valve dysfunction at a later stage.     

Noninvasive evaluation of mid-left ventricular obstruction by two-dimensional and Doppler echocardiography and color flow Doppler echocardiography

Three patients with midventricular obstruction resulting from three different pathophysiologic mechanisms and differing anatomic bases for the development of obstruction are presented. In the first patient, a membrane-like structure appeared to cause some fixed obstruction, but a superimposed dynamic component to the obstruction was also evident. Papillary muscle hypertrophy with approximation of the papillary muscles during systole was the mechanism in the second patient. In the third patient, apical infarction with hyperdynamic contraction of the mid- and basal portions of the myocardium appeared to be the pathophysiologic mechanism. Color flow Doppler echocardiography was particularly useful in localizing the site of obstruction and allowed further evaluations by pulsed and continuous-wave Doppler techniques to precisely determine pressure gradients.     

Diastolic right ventricular hemodynamics in right ventricular overloads assessed by pulsed Doppler echocardiography

To assess right ventricular (RV) filling dynamics, RV inflow velocity patterns of pulsed Doppler echocardiograms and jugular pulse tracings were analyzed in 59 patients with various types of RV overloads and in 20 normal subjects. The patients were classified as (1) RV volume overload group (RVVO) consisting of 25 patients with atrial septal defect (ASD) without pulmonary hypertension (PH), (2) RV pressure overload group consisting of 26 patients including 12 with primary pulmonary hypertension (PPH), eight with mitral stenosis, three with pulmonary stenosis and three with cor pulmonale, and (3) RV volume and pressure overload group consisting of eight patients with ASD and PH. The acceleration time (AT), deceleration time (DT) and the A/D ratio were measured from the RV inflow velocity patterns, and v-y interval and the y/H ratio were measured from jugular pulse tracings. The results were as follows: 1. AT was significantly prolonged in groups with pressure overload as well as pressure and volume overload compared with that of the normal controls. 2. DT was significantly prolonged in all overload groups compared with that of the normal controls except for PPH, and was particularly prolonged in the group with pressure overload. 3. The A/D ratio was significantly increased in all overload groups, particularly in the groups with pressure overload. 4. In patients with volume overloads, the v-y interval was longer and the y/H ratio was higher than in the normal controls. RVVO shifted to the right and superiorly. The reverse was true in the pressure overload group, and the high ratios were observed in the remainder. 5. In 12 patients with ASD evaluated pre- and postoperatively, AT, DT and the A/D ratio were restored to normal after surgery. These findings suggest that RV volume overload was characterized not only by increased inflow velocity during the rapid filling period, but prolongation of this period and compensatory increase of atrial inflow velocity. However, the pressure overload group had disturbed rapid filling and a decrease in end-diastolic RV compliance. The group with both pressure and volume overloads was between the two. In conclusion, the mode of RV filling in patients with RV overload showed various patterns depending on the type of overload. The RV inflow velocity pattern recorded by pulsed Doppler echocardiography is of use in discriminating these varieties.