Impaired left ventricular diastolic function in children with chronic renal failure

BACKGROUND: Diastolic dysfunction is frequent in adults with renal failure. However, in children with mild-to-moderate chronic renal insufficiency (CRI), it has not been evaluated. We compared diastolic function and assessed risk factors associated with diastolic dysfunction in children with CRI with those on dialysis. METHODS: Thirty-three children with CRI, 17 on chronic dialysis, and 33 control patients, had echocardiography performed. Early diastole was assessed using indices of left ventricular (LV) relaxation derived from transmitral and tissue Doppler, and reported as the peak E/A wave ratio, and septal mitral annular velocities (Em). Late diastole was determined using an index of LV compliance (E/Em ratio). Left atrial (LA) dimension was also determined. RESULTS: Children with CRI had worse diastolic function (lower Em, and higher E/Em ratio than control patients, P < 0.001). Dialysis patients had worse diastolic function (lower E/A ratio and Em, and higher E/Em ratio, P < 0.001) than CRI children. LA dimension was higher in renal patients when compared with control patients (P < 0.001). In children on dialysis, LV relaxation (Em) was significantly related to left ventricular mass (LVM) index (r=-0.58, P= 0.04), and LV compliance (E/Em) was significantly associated with LA index (r= 0.67, P= 0.01), LVM index (r= 0.75, P < 0.01), hemoglobin level (r=-0.65, P= 0.02), serum phosphorus (r= 0.56, P= 0.05), and calcium-phosphorus ion product (r= 0.59, P= 0.04). CONCLUSION: Our results indicate that diastolic dysfunction is already present in children with mild-to-moderate CRI. Worse diastolic function in dialysis patients might be related to LV hypertrophy. The results suggest that children with advanced renal failure and diastolic dysfunction may be at risk for ultimate worsening of cardiac function over time.     

Prevalence of left ventricular diastolic filling abnormalities in adult cardiac surgical patients: an intraoperative echocardiographic study.

The incidence of left ventricular (LV) diastolic abnormalities in adult cardiac surgical patients has not previously been adequately investigated. The present study was performed to characterize LV diastolic filling patterns by performing transesophageal Doppler echocardiographic (TEE) studies in patients undergoing cardiac surgical procedures and thus indirectly assess diastolic function in these patients. Doppler TEE studies were performed and transmitral flow (TMF) and pulmonary venous flow (PVF) velocities were recorded in 104 patients intraoperatively. Peak early (E) and late (A) TMF velocities and systolic (S) and diastolic (D) forward PVF velocities were assessed and deceleration time (DT) was measured in all patients. For analysis, the study patients were classified into three groups according to the ratio of the TMF E to A velocity curves: group I with E/A ratio less than 1.0, group II with E/A ratio of 1.0 to less than 2.0, and group III with E/A ratio of 2.0 or greater. A filling pattern of abnormal LV relaxation was found in 73 patients (E/A < 1.0), a normal or pseudonormal pattern was present in 27 patients (1.0 < or = E/A < or = 2.0), and restrictive filling in 4 patients (E/A > 2.0). Patients with impaired relaxation had a greater incidence of recent myocardial infarction and congestive heart failure (CHF) than those with normal or pseudonormal filling patterns. Within group II, patients with CHF had higher TMF E deceleration rates and lower PVF S/D ratios compared with those without CHF (P < .05). Doppler echocardiographic examination of TMF and PVF velocities suggests that abnormalities in diastolic function are prevalent in adult cardiac surgical patients.     

Effects of altered volume loading on left ventricular hemodynamics and diastolic filling during hemodialysis

BACKGROUND: Changes in the circulating volume associated with hemodialysis (HD) resulted in alternations of left ventricular (LV) filling. However, previous studies offered conflicting findings. This study thus evaluated the impact of HD on LV diastolic filling indices and hemodynamics. MATERIALS AND METHODS: Forty patients with end-stage renal disease were studied by Doppler echocardiography immediately before and after HD. The cardiac size, volume and mass were determined by M-mode and two-dimensional echocardiography. LV diastolic filling parameters and hemodynamics were assessed from mitral inflow using Doppler echocardiography. RESULTS: Left atrial and LV dimension, LV volume, and LV mass decreased significantly after HD (p<0.001). Cardiac output declined from 5.74+/-1.37 to 4.98+/-1.27 L/min (p<0.001), whereas, the ejection fraction remained unchanged. HD elicited marked changes in the early diastolic E (95.1+/-20.5 to 70.3+/-18.2 cm/s, p<0.001) and late atrial filling A velocities (104.3+/-20.9 to 88.9+/-16.9 cm/s, p<0.001). In addition, correction of the deceleration time of E and isovolumic relaxation time prolonged significantly (p=0.011 and p<0.001, respectively). CONCLUSIONS: Findings in this study indicate that HD altering the loading condition significantly influenced the LV diastolic function and hemodynamics. Moreover, Doppler echocardiography provides an effective means of assessing the effects on LV diastolic filling and hemodynamics during HD.     

Association between Diastolic Dysfunction by Color Tissue Doppler Imaging and Vascular Calcification on Plain Radiographs in Dialysis Patients

Background/Aim: Diastolic dysfunction is frequently associated with left ventricular hypertrophy, which is indicative of future cardiovascular events. Vascular calcification (VC) is known to be associated with coronary artery disease in dialysis patients. The present study was to determine the interrelationship between LV diastolic dysfunction by tissue Doppler imaging and VC on plain radiographs in dialysis patients. Methods: Fifty-six dialysis patients were recruited and VC scores were evaluated by plain radiographic film. The ratio of early diastolic transmitral inflow velocity (E) to early diastolic mitral annular velocity (E') was measured by tissue Doppler imaging. We defined diastolic dysfunction as an E/E' ratio >15 on tissue Doppler imaging. Results: Patients with diastolic dysfunction showed a higher percentage of coronary artery disease history, abdominal aortic calcification (AAC) scores ≥5, high LV mass index, and high left atrium volume compared to patients without diastolic dysfunction. The E/E' ratio was significantly higher in patients with significant VC, VC scores of the pelvis and hands ≥3, and AAC scores ≥5 on plain radiographs. AAC scores ≥5 were considered an independent predictor of diastolic dysfunction. Conclusion: VC on plain radiographs is associated with the E/E' ratio and AAC scores ≥5 are important clues for LV diastolic dysfunction in dialysis patients.     

Left ventricular function by 'conventional' and 'tissue Doppler' echocardiography in paediatric dialysis patients

Aim:   Cardiovascular abnormalities are common in children with chronic kidney disease (CKD). Left ventricular (LV) structure and functions have been extensively studied by conventional pulse-wave Doppler echocardiography (cPWD), however, tissue Doppler imaging (TDI) is a relatively new echocardiography method. The aims of this study were to evaluate LV diastolic function in paediatric dialysis patients using cPWD and TDI methods, and to compare the findings obtained with two modalities.
Methods:   This study included 38 children and adolescents on dialysis (14 haemodialysis and 24 peritoneal dialysis, duration of dialysis 58.0 ± 32.8 months) and 16 age- and sex-matched healthy subjects.
Results:   The mean left ventricular mass index (LVMI) was significantly higher in the patient group ( P  < 0.001) and the most common cardiac geometry was concentric LV hypertrophy (55%). There was no significant difference in LV systolic function between patient and control groups. However, dialysis patients had worse LV diastolic function both according to cPWD (lower E/A ratio) and TDI (lower Em/Am ratio) than the healthy subjects ( P  < 0.001 and P  = 0.001, respectively). Also, the index of LV filling pressure (E/Em ratio) obtained by the combination of cPWD and TDI was significantly higher in the patients ( P  < 0.001). Cumulative dose of calcium-based phosphate binder (CBPB), diastolic blood pressure and LVMI were the independent predictors of E/Em ratio.
Conclusion:   Our study shows that LV diastolic dysfunction is common in paediatric dialysis patients and TDI findings correlate well with cPWD findings. Similarly, higher dose intake of CBPB, hypertension and LV hypertrophy have a negative effect on LV filling pressure suggesting diastolic function.     

Abnormal diastolic left ventricular filling by pulsed Doppler echocardiography in patients on continuous ambulatory peritoneal dialysis.

To determine characteristics of diastolic left ventricular (LV) function in patients on continuous ambulatory peritoneal dialysis (CAPD), two groups of CAPD patients without (n = 23; group 1) vs with (n = 25; group 2) LV hypertrophy (greater than 13 mm) were compared with a group of untreated non-renal hypertensive patients with LV hypertrophy (n = 11; group 3) using Doppler-echocardiography. Age and body surface area were comparable in all three groups, mean CAPD-duration (32 +/- 28 vs 26 +/- 23 months; p = NS) was comparable in renal patients. LV systolic function in echocardiography (LVEF: 62 vs 64 vs 63%) and systolic time intervals were normal and comparable in all three groups. Atrial maximum filling velocities (96 +/- 25 vs 91 +/- 25 vs 67 +/- 8 cm/s) were comparably increased, the ratio of maximal early/atrial filling velocities was comparably decreased (0.73 +/- 0.25 vs 0.77 +/- 0.21 vs 0.99 +/- 0.05) in both groups of renal patients as compared to group 3 (p less than 0.05-0.01). Atrial filling fractions were increased in all three groups, more pronounced in group 1 than in group 3 (50 +/- 11 vs 40 +/- 7%; p less than 0.05). The normal correlation of Doppler parameters with age and with LV radius/thickness ratio was altered in renal patients such that high patient age tended to have an additional negative influence on LV diastolic function of hypertrophied, but not of normal myocardium. Isovolumic relaxation time was prolonged in all three groups (134 +/- 38 vs 131 +/- 34 vs 116 +/- 17 ms; p = NS). We conclude that in patients on CAPD, diastolic LV filling is impaired both in normal and hypertrophied myocardium. High age is a factor that further attributes to diastolic dysfunction of hypertrophied myocardium in CAPD.     

Preload dependence of new Doppler techniques limits their utility for left ventricular diastolic function assessment in hemodialysis patients

Left ventricular (LV) hypertrophy leads to diastolic dysfunction. Standard Doppler transmitral and pulmonary vein (PV) flow velocity measurements are preload dependent. New techniques such as mitral annulus velocity by Doppler tissue imaging (DTI) and LV inflow propagation velocity measured from color M-mode have been proposed as relatively preload-independent measurements of diastolic function. These parameters were studied before and after hemodialysis (HD) with ultrafiltration to test their potential advantage for LV diastolic function assessment in HD patients. Ten patients (seven with LV hypertrophy) underwent Doppler echocardiography 1 h before, 1 h after, and 1 d after HD. Early (E) and atrial (A) peak transmitral flow velocities, peak PV systolic (s) and diastolic (d) flow velocities, peak e and a mitral annulus velocities in DTI, and early diastolic LV flow propagation velocity (V(p)) were measured. In all patients, the E/A ratio after HD (0.54; 0.37 to 1.02) was lower (P < 0.01) than before HD (0.77; 0.60 to 1.34). E decreased (P < 0.01), whereas A did not. PV s/d after HD (2.15; 1.08 to 3.90) was higher (P < 0.01) than before HD (1.80; 1.25 to 2.68). Tissue e/a after HD (0.40; 0.26 to 0.96) was lower (P < 0.01) than before HD (0.56; 0.40 to 1.05). Tissue e decreased (P < 0.02), whereas a did not. V(p) after HD (30 cm/s; 16 to 47 cm/s) was lower (P < 0.01) than before HD (45 cm/s; 32 to 60 cm/s). Twenty-four hours after the initial measurements values for E/A (0.59; 0.37 to 1.23), PV s/d (1.85; 1.07 to 3.38), e/a (0.41; 0.27 to 1.06), and V(p) (28 cm/s; 23 to 33 cm/s) were similar as those taken 1 h after HD. It is concluded that, even when using the newer Doppler techniques DTI and color M-mode, pseudonormalization, which was due to volume overload before HD, resulted in underestimation of the degree of diastolic dysfunction. Therefore, the advantage of these techniques over conventional parameters for the assessment of LV diastolic function in HD patients is limited. Assessment of LV diastolic function should not be performed shortly before HD, and its time relation to HD is essential.     

Challenges for ‘diastology’: contributions from Japanese researchers

Diastology is a study to treat diastole of the heart. Transmitral flow and pulmonary venous flow velocities recorded by pulsed Doppler echocardiography provide more important information about left ventricular (LV) diastolic dysfunction [left atrial (LA)?LV coupling] than cardiac catheterization in clinical practice; however, these waveforms are influenced by loading conditions, particularly preload. The early diastolic mitral annular and LV wall motion indices measured by tissue Doppler echocardiography can evaluate LV relaxation abnormality and filling pressure by being relatively preload independent. In addition, the role of concomitant systolic longitudinal dysfunction is well characterized in asymptomatic patients and in patients with heart failure and preserved ejection fraction. Two-dimensional speckle tracking echocardiography is an angle-independent method, and has the potential to evaluate the contraction and relaxation abnormalities in the longitudinal, circumferential, and radial directions of the LV myocardium as well as LV torsion/untwisting and, moreover, deformation of the LA myocardium and large arterial wall. As a result, this new technique can facilitate the early detection of impaired LA?LV?arterial coupling in patients before occurrence of overt heart failure symptoms.     

Left ventricular systolic and diastolic function and carotid intima-media thickness in pediatric dialysis patients

Background  Cardiovascular complications are common in patients with end-stage renal disease (ESRD). We aimed to investigate left ventricular (LV) function and carotid intima-media thickness (cIMT) in children and adolescents with ESRD. Methods  This study included 38 ESRD patients (15 hemodialysis and 23 peritoneal dialysis) and 17 age- and sex-matched healthy subjects. Results  The ESRD patients had significantly lower mean mitral E/A ratio, and higher left ventricular mass index (LVMI) and cIMT than the control group. Compared with PD patients, HD patients had worse LV diastolic function. In stepwise linear regression analysis, LVMI (P = 0.043) and hemoglobin (P = 0.015) turned out to be independent variables for predicting diastolic dysfunction (reduced E/A ratio), and the only significant predictor of cIMT was indexed diastolic blood pressure (DBP) (P = 0.035). Conclusion  Cardiovascular structure and function abnormalities are also common in pediatric dialysis patients, as in adults. Furthermore our data indicated that hemodialysis was disadvantageous for preserving LV diastolic function as compared with peritoneal dialysis.     

Left ventricular diastolic dysfunction by tissue Doppler echocardiography in pediatric chronic kidney disease

Background

Myocardial dysfunction is common in chronic kidney disease (CKD) and related to poor outcomes. New non-invasive methods to assess cardiac function have been introduced, but comparative studies evaluating their clinical usefulness in pediatric CKD are lacking. We studied left ventricular (LV) function in pediatric CKD and renal transplant patients, comparing conventional pulse-wave Doppler echocardiography (cPWD) with newer tissue Doppler imaging (TDI) and relating the results to known cardiovascular risk factors.

Methods

The study included 34 children/adolescents with CKD stages 2–5, 44 renal transplant patients and 19 patients with a normal renal function. The mean age was 11.4 (range 0.8–18.8) years.

Results

Both patient groups had significantly lower LV diastolic function than those with a normal renal function. The most sensitive determinants were TDI E′/A′ and cPWD E/TDI E′ ratios. In a stepwise linear regression analysis, high blood pressure, young age and the presence of albuminuria all independently predicted LV diastolic function.

Conclusions

Our study confirms the high prevalence of LV diastolic dysfunction in pediatric CKD patients and following renal transplantation, where TDI appears to be more sensitive than cPWD in assessing early myocardial dysfunction. Our results also underline the importance of preventive measures, such as rigorous blood pressure control, in pediatric CKD.     

Left ventricular function in patients with chronic kidney disease evaluated by colour tissue Doppler velocity imaging.

BACKGROUND: Cardiovascular disease is the leading cause of death in chronic kidney disease (CKD) patients. Tissue Doppler velocity imaging (TVI) is a new objective method that accurately quantifies myocardial tissue velocities, deformation, time intervals and left ventricular (LV) filling pressure. In this study, TVI was compared with conventional echocardiography for the assessment of left ventricular (LV) function in pre-dialysis patients with different stages of CKD. The results obtained by TVI were used to analyse possible relationships between LV function and clinical factors such as hyperparathyroidism and hypertension that could influence LV function. METHODS: Conventional echocardiography and TVI images were recorded in 40 patients (36 men and 4 women, mean age 60+/-14 years, range 28-80 years) and in 27 healthy controls (21 men and 6 women, mean age 58+/-17 years, range 28-82 years). Twenty-two patients had mild/moderate CKD (CCr>29 ml/min; Group 1) and 18 patients had severe CKD (CCr相似文献   

Comparison of Echocardiographic Changes Associated with Hemodialysis and Renal Transplantation

Abstract: Long-term hemodialysis has been reported to cause progression of left ventricular (LV) hypertrophy with a tendency toward asymmetric septal hypertrophy. Renal transplantation is believed to reverse some of these changes. The aim of this prospective study was to compare the effects of long-term hemodialysis and of successful renal transplantation on cardiac structure and function assessed by echocardiography. Fifty-three patients were submitted to two echocardiographic evaluations separated by a 30 ± 8 month interval. At the first control, all patients were on hemodialysis; at the second, 36 patients remained on dialysis while 17 had been submitted to renal transplantation. Age (44 ± 13 vs. 40 ± 10 years), gender (male, 50% vs 53%), and duration of dialysis at the initiation of the study (43 ± 34 vs. 47 ± 32 months) were comparable in the 2 groups. The prevalences of LV hypertrophy were 83% (first control) and 69% (second control) in the dialysis group and 82% and 71% in the transplant group. Comparisons between the two periods within each group showed that hemodialysis was associated with a significant reduction of the E/A ratio (1.25 ± 0.4 vs. 1.02 ± 0.4, p < 0.001) and systolic (155 ± 28 vs. 137 ± 26 mm Hg, p < 0.001) and diastolic (94 ± 21 vs. 84 ± 16 mm Hg, p < 0.05) blood pressure, and no change in LV mass index (171 ± 51 vs. 156 ± 43 g/m², NS). In the transplanted group, there were reductions in the E/A ratio (1.42 ± 0.6 vs. 1.10 ± 0.4, p < 0.05) and in LV diastolic dimension (50 ± 7 vs. 46 ± 5 mm, p < 0.05), but not in systolic (155 ± 27 vs. 152 ± 31 mm Hg, NS) or diastolic (97 ± 11 vs. 97 ± 20 mm Hg, NS) blood pressure. The LV mass index also did not change significantly (157 ± 51 vs. 133 ± 31 g/m², NS). Left atrium dimension, LV posterior wall thickness, interventricular septum thickness, and fractional shortening were not significantly changed in either group. Asymmetric septal hypertrophy was not observed. It is concluded that patients treated by long-term hemodialysis did not present progression in the degree and prevalence of LV hypertrophy over time while systolic function was preserved and diastolic function deteriorated. Contrary to previous reports, successful renal transplantation did not cause a reduction in LV hypertrophy and also failed to improve LV diastolic function.     

Serum cystatin C and left ventricular diastolic dysfunction in children with chronic kidney disease

Previous studies indicate that serum cystatin C predicts incident heart failure in older adults. Children with chronic kidney disease (CKD) develop left ventricular (LV) diastolic dysfunction, often the initial abnormality of cardiac function. We hypothesized that cystatin C might predict LV diastolic dysfunction in children with CKD. Fifty-seven subjects, aged 6–21 years, with stage 2–4 CKD underwent echocardiography. Diastole was assessed from transmitral Doppler [maximum early (E wave) and late (A wave) diastolic flow velocities (E/A ratio)] and from tissue Doppler [septal mitral annular peak velocities (E′)]. LV filling pressures were determined, using a ratio of E/E′. Fourteen (25%) patients had low E′ and 15 (26%) had high E/E′. Children with abnormal E′ or E/E′ had significantly higher cystatin C levels than children with normal indices (P<0.05). Neither serum creatinine nor measured glomerular filtration rate (GFR) significantly correlated with E’ or E/E’. Stepwise multiple regression analysis showed that cystatin C (β=−0.825, P=0.023) and left ventricular mass (LVM) index (β=0.099, P=0.006) independently predicted E′; LVM index independently predicted E/E′ (β=0.0173, P=0.01). We conclude that, in contrast to measured GFR or serum creatinine level, elevated serum cystatin C might be associated with diastolic dysfunction in children with CKD.     

Segmental Differences of Impaired Diastolic Relaxation Following Cardiopulmonary Bypass Surgery in Children: A Tissue Doppler Study

Impaired myocardial relaxation is an important aftereffect of cardiopulmonary bypass (CPB). Infants with their immature calcium metabolism may be particularly vulnerable. However, it has been difficult to quantitate diastolic dysfunction clinically. This study used tissue Doppler to measure regional diastolic myocardial velocities in 31 pediatric patients undergoing open heart surgery. Color tissue Doppler images were acquired in the operating room before and 8 and 24 h post CPB surgery. Early (E) and atrial (A) diastolic velocities were determined. Long axis motion was assessed from apical views near the mitral and tricuspid rings and radial wall motion from the parasternal view. The study included 31 children aged 3.6 ± 4.4 years (6 days to 16 years), with a mean weight of 14.7 ± 13.7 kg and body surface area of 0.59 ± 0.35 m². Tissue Doppler analysis of regional wall motion revealed abnormal left ventricle (LV) and right ventricle (RV) diastolic relaxation in the early postoperative phase after CPB. Initially, all segments were significantly altered, but by 24 h, regional differences became apparent: LV radial wall motion was recovered, while longitudinal fibers in LV and RV appeared to be less resilient. RV myocardial mechanics were most abnormal. Tissue Doppler analysis may deepen our understanding of myocardial recovery and offers a sensitive tool to compare different cardioprotective strategies.     

The influence of low calcium dialysate on left ventricular diastolic function in peritoneal dialysis patients

Left ventricular (LV) diastolic function was found to be a significant predictor of cardiovascular events and general mortality in dialysis. Studies have indicated that dialysate calcium concentrations were significantly associated with cardiac function. However, the relationship between low calcium dialysate and LV diastolic function has not been clear. The aim of this study was to investigate the influence of low calcium dialysate on cardiac function in peritoneal dialysis (PD) patients. A total of 60 PD patients were enrolled in this study, with a calcium content of the PD solution of 1.25?mmol/L in 30 patients (low-calcium group) and 1.75?mmol/L in 30 patients (standard-calcium group). Standard M-mode and two-dimensional ultrasound measurements were applied to detect the cardiac function. After 12-month follow-up, we found no significant difference in blood pressure, calcium, phosphorus, parathyroid hormone (PTH), etc., between the two groups. Residual renal function (RRF), which is associated with LV cardiac function, was significantly decreased in the standard-calcium group compared with the low-calcium group (5.64?±?3.23 vs. 9.38?±?3.17, p?=?.001). Compared with the low-calcium group, E_max (peak early diastolic velocity) and A_max (peak late diastolic velocity) were significantly decreased (p?p?相似文献   

Left ventricular diastolic function in patients on maintenance haemodialysis

SUMMARY: The aim of this study was to elucidate the differences in left ventricular (LV) diastolic function between patients on maintenance haemodialysis (HD) with LV hypertrophy (LVH) and those with LVH from other causes. Twenty HD patients (HD group), 11 patients with hypertensive heart disease (HHD group), 11 with hypertrophic cardiomyopathy (HCM group) and 11 age-matched healthy individuals (N group) were examined using echocardiography. Compared with the HCM group, the HD and HHD groups had smaller total LV wall thickness and left atrial dimension, a higher ratio of LV end-diastolic dimension to LV posterior wall thickness, a shorter isovolumic relaxation time and a higher ratio of peak flow velocity of early to late LV fillings (E/A). There was a correlation between LV mass index or E/A and systolic blood pressure. These results indicate that HD patients have an LV diastolic dysfunction similar to that observed in HHD patients but which is less severe than that found in HCM patients. It seems reasonable to control hypertension in HD patients in order to favourably influence LV diastolic function.     

Reduced compliance of left ventricle

Diastolic function is essential for efficient systolic performance. A normal diastole allows left ventricle (LV) filling to occur under normal intracavitary pressure. It is an energy dependent process, as such affected by ischemia. Several factors influence diastolic function of the LV: the mitral valve area, the gradient between atrium and ventricle, LV relaxation and compliance, atrial compliance, the presence of sinus rhythm, the end-systolic volume. Echocardiography is the principal diagnostic tool to assess LV diastolic function noninvasively in clinical practice. Doppler evaluation allows to analyse each phase of LV diastole through measurement of transmitral and pulmonary veins flows velocities. Tissue Doppler echocardiography and color M-mode Doppler have also been introduced in the study of diastole. The use of echocardiography in the setting of diastolic dysfunction in ICU and operatory room has relevant implications in the management of haemodynamic instability, in vasoactive d rugs titration, in the detection of myocardial ischemia, and in performing prognostic stratification. These information can guide the management of cardiac patients undergoing cardiac and non cardiac surgery, in the perioperative phase, as well as in the management of critical ICU patients. On this basis evaluating the LV filling properties can contribute to improve the quality of treatments in such challenging situations.     

A randomised controlled trial comparing the effects of propofol with isoflurane in patients with diastolic dysfunction undergoing coronary artery bypass graft surgery

There is a strong association between pre‐operative diastolic dysfunction and difficulty in weaning from cardiopulmonary bypass. We compared the effects of propofol and isoflurane on left ventricular diastolic function in patients with pre‐existing diastolic dysfunction undergoing coronary artery bypass grafting. We randomly allocated 60 patients to receive either propofol or isoflurane anaesthesia, and assessed left ventricular diastolic function using transoesophageal echocardiography. We measured early (E), late (A) diastolic velocities, E/A ratio, A‐wave duration and deceleration time using pulsed wave Doppler, and early (Em), late (Am) diastolic velocities of the mitral annulus, Em/Am ratio and isovolumetric relaxation time using tissue Doppler. We measured pulmonary venous flow velocity and recorded values for the peak systolic flow velocity (S), peak diastolic flow velocity (D), S/D ratio, peak reverse atrial flow velocity and duration of reverse atrial flow. All data were recorded immediately after tracheal intubation as a baseline, 5 min before sternotomy (T₁), 5 min before aortic cannulation (T₂) and 15 min after weaning from cardiopulmonary bypass (T₃). Both propofol and isoflurane improved left ventricular diastolic function as evidenced by significant increases in E/A ratios, and significant decreases in deceleration time and isovolumetric relaxation time; the improvement was greater in the isoflurane group (between groups, p = 0.001 for both E/A ratio and deceleration time at T₁ and T₂ and p = 0.006 for isovolumetric relaxation time at both T₁ and T₂). Furthermore, Em/Am ratio, S, D and S/D ratios were significantly better in the isoflurane group. The administration of isoflurane during cardiac surgery improves diastolic function comparatively more than propofol.     

The effects of acute normovolemic hemodilution on left ventricular systolic and diastolic function in the absence or presence of beta-adrenergic blockade in dogs

Acute normovolemic hemodilution (ANH) increases cardiac output because of a reduction in blood viscosity and enhancement of left ventricular (LV) contractility. The status of LV function, especially LV diastolic function during ANH, remains controversial. We therefore examined LV systolic and diastolic function during ANH. Sixteen dogs were anesthetized with isoflurane in the absence (Group 1) and presence (Group 2) of beta-adrenergic blockade (propranolol 1 mg/kg). LV contractility was quantified by the slope (M(w)) of the stroke work and end-diastolic volume relation. Diastolic function was evaluated with the time constant of LV relaxation (T), chamber stiffness constant (K(c)), peak LV diastolic filling rate during early filling (peak E) and atrial contraction (peak A), and ratio of peak E to peak A (E/A). Normovolemic exchange of blood (50 mL/kg) for 6% hydroxyethyl starch (ANH50) significantly increased M(w) in Group 1 but not in Group 2. In both groups, ANH50 significantly decreased T. ANH50 significantly increased peak E in both groups and peak A in Group 1, and it did not change the E/A ratio or K(c) in either group. ANH causes positive inotropic effects and enhances diastolic function without beta-blockade. Even after beta-adrenergic blockade, ANH improves diastolic function through the reduction of LV ejection impedance. IMPLICATIONS: Acute normovolemic hemodilution enhances LV (left ventricular) diastolic function by alterations in the LV loading condition produced by hemodilution, which mainly contributes to a compensatory increase in cardiac output.     

LV mass index significantly impacts on patient and renal outcomes in patients with coronary artery bypass grafting and poor left-ventricular function

BACKGROUND: A recent report demonstrated that the presence of left ventricular hypertrophy was an independent predictor of mortality in patients with coronary artery bypass grafting (CABG) severely depressed left ventricular function. However, the impact of left ventricle (LV) mass index on the renal and patient outcomes in such patients with CABG has previously not been addressed. The present study thus considers this group of patient and uses LV mass index to assess renal and patient outcomes for these patients. MATERIAL AND METHOD. All patients who arrived at the emergency room with severe cardiac dysfunction (EF < 60%), triple vessel disease, and required CABG and LV hypertrophy (LVH) (LV mass index gamma110 g/m2 in women, gamma134 g/m2 in men) were admitted preoperatively to the intensive care unit (ICU) for supportive intervention from January 1, 1998 to January 1, 2001. Of all LVH patients, 44 underwent CABG, and were divided into two groups according to LV mass index. RESULTS: Of all patients, 72.7% had severe echocardiographic LVH. The echocardiographic data of both dialysis and non-dialysis groups showed no difference with respect to echocardiographic findings. Histories of myocardial infarction were more frequent in the severe LVH group that in the mild LVH group. As for pre-operative systolic blood pressure and diastolic blood pressure, mean systolic and diastolic blood pressure values were significantly lower in the severe LVH group. Ejection fraction was also significantly lower in the severe LVH group than in the mild LVH group. The patients in the severe LVH group were significantly more likely to have received hemodialysis following CABG surgery (62.5% vs. 33.4%, p < 0.05). Mortality was higher in the higher LV mass index group that in the lower LV mass index group (56.2% vs. 25%, p < 0.05). CONCLUSION; Patients with a significantly higher LV mass index usually manifest lower pre-operative blood pressure and poor cardiac function. Consequently, these patients will have a poor renal outcome and higher mortality.