The relationship between early left ventricular myocardial alterations and reduced coronary flow reserve in non-insulin-dependent diabetic patients with microvascular angina

Incremental value of non-invasive myocardial work for the evaluation and prediction of coronary microvascular dysfunction in angina with no obstructive coronary artery disease

Background

Evidence suggests that patients suffering from angina with no obstructive coronary artery disease (ANOCA) experience coronary microvascular dysfunction (CMD). We aimed to understand the diagnosis value of noninvasive myocardial work indices (MWIs) with left ventricular pressure-strain loop (LV PSL) by echocardiography in ANOCA patients with CMD.

Methods

97 patients with ANOCA were recruited. All subjects underwent standard echocardiography with traditional ultrasound parameters, two-dimensional speckle-tracking echocardiography with global longitudinal strain (GLS), LV PSL with MWIs include global work index (GWI), global constructive work (GCW), global waste work (GWW) and global work efficiency (GWE). In addition, all enrolled cases underwent high-dose adenosine stress echocardiography (SE) with coronary flow velocity reserve (CFVR). CMD was defined as CFVR <2.0.

Results

Of the 97 patients with ANOCA, 52 were placed in the CMD group and 45 in the control group. GWI and GCW were decreased significantly in the CMD group compared with the control group (P < 0.001 for both). GWI and GCW were moderately correlated with CFVR (r = 0.430, P < 0.001 and r = 0.538, P < 0.001, respectively). In the multiple logistic regression analyses, GCW was identified as the only independent echocardiography parameter associated with CMD after adjusting for age and baseline APV [OR (95%CI) 1.009 (1.005-1.013); P < 0.001]. Moreover, the best predictor of CMD in patients with ANOCA using receiver operating characteristic (ROC) curve was GWI and GCW, with an area under the curve (AUC) of 0.800 and 0.832, sensitivity of 67.3% and 78.8%, specificity of 80.0% and 75.6%, respectively.

Conclusion

MWIs with LV PSL is a new method to detect LV systolic function noninvasively in ANOCA patients with CMD.

[Type 2 diabetes mellitus and coronary artery disease: features of perfusion volume computed tomography of the heart in a pharmacological test with adenosine triphosphate]

AIM

To study myocardial perfusion in patients with coronary artery disease (CAD) with and without type 2 diabetes mellitus (DM) using volumetric computed tomography (VCT) of the heart with a pharmacological test with adenosine triphosphate (ATP).

MATERIALS AND METHODS

The study included 93 patients, of which 18 had CAD with DM, and 50 had CAD without DM. All patients underwent one of the stress tests, cardiac VCT with ATP test, invasive coronary angiography, or CT coronary angiography. Left ventricle (LV) myocardial perfusion was evaluated for hypoperfusion zones and the calculation of semi-quantitative indices: decrease of LV myocardial density, LV myocardial perfusion index, transmural perfusion coefficient, and our proposed new indicator - myocardial perfusion reserve (MPR).

RESULTS

The MPR index value in the hypoperfusion zones in patients with CAD and DM was 0.64 [0.62-0.66], in patients with CAD without diabetes 0.65 [0.63-0.66]; p=0.4; the value of the transmural perfusion coefficient in the areas of abnormal LV myocardial perfusion in patients with CAD and DM was 0.81 [0.80-0.86] versus 0.83 [0.80-0.85] in patients with CAD without DM (p=0.6). More hypoperfusion segments were observed in patients with CAD and DM (33.3%) compared to those without DM (14%; p=0.029). The MPR index in the hypoperfusion zones in patients with CAD with intact coronary arteries (CA) and DM was 0.56 [0.54-0.60] versus 0.55 [0.54-0.62] in patients with CAD with intact CA without DM; p=0.2.

CONCLUSION

In patients with CAD and type 2 DM, according to the VCT with ATP test, more foci hypoperfusion areas were detected, regardless of the severity of coronary artery involvement, compared with patients with CAD without DM, which may be due to the microangiopathy in the myocardium. The similarity of the MPR parameters in the hypoperfusion zones associated with hemodynamic stenosis of the CA and with intact CAs indicates the ischemic genesis of these zones. For citation: Soboleva GN, Minasyan AA, Gaman SA, Rogoza AN, Molina LP, Soboleva TV, Shariya MA, Ternovoy SK, Karpov YuA. Type 2 diabetes mellitus and coronary artery disease: features of perfusion volume computed tomography of the heart in a pharmacological test with adenosine triphosphate. Terapevticheskii Arkhiv (Ter. Arkh.). 2023;95(4):309-315. DOI: 10.26442/00403660.2023.04.202158.

Subclinical systolic dysfunction detected by 2D speckle tracking echocardiography in adults with diabetes mellitus: systematic review and meta-analysis of 6668 individuals with diabetes mellitus and 7218 controls

PURPOSE

Speckle tracking echocardiography (STE) can help to identify subclinical features of diabetic cardiomyopathy (DCM). There is, however, significant heterogeneity in the reported strain values in literature. We performed a systematic review and meta-analysis to compare cardiac systolic strain values assessed by 2D-STE in asymptomatic adults with diabetes mellitus (DM) and healthy controls.

METHODS

Five databases were searched, and a total of 41 valid studies (6668 individuals with DM and 7218 controls) were included for analysis. Pooled mean in each group and mean difference (MD) for left ventricular global longitudinal strain (LVGLS), LV global circumferential strain (LVGCS), LV global radial strain (LVGRS), LV longitudinal systolic strain rate (LVSR), left atrial reservoir strain (LARS) and right ventricular GLS (RVGLS) were assessed.

RESULTS

Patients with DM had overall 2 units lower LVGLS than healthy subjects 17.5% [16.8, 18.3], vs 19.5 [18.7, 20.4], MD = - 1.96 [- 2.27, - 1.64]. Other strain values were also lower in patients with DM: LVGCS (MD = - 0.89 [- 1.26, - 0.51]); LVGRS (MD = - 5.03 [- 7.18, - 2.87]); LVSR (MD = - 0.06 [- 0.10, - 0.03]); LARS (MD = - 8.41 [- 11.5, - 5.33]); and RVGLS (MD = - 2.41 [- 3.60, - 1.22]). Meta-regression identified higher body mass index (BMI) as the single contributor to worse LVGLS, LVGCS and LVSR. Those with higher Hemoglobulin A1c had worse RVGLS.

CONCLUSION

Myocardial strains were reduced in whole heart in patients with DM. The largest reduction was observed in LA reservoir strain, followed by RVGLS and LVGLS. Higher BMI in patients with DM is associated with worse LV strain values.

Research on the Method of Predicting Fractional Flow Reserve Based on Multiple Independent Risk Factors

The use of diameter stenosis (DS), as revealed by coronary angiography, for predicting fractional flow reserve (FFR) usually results in a high error rate of detection. In this study, we investigated a method for predicting FFR in patients with coronary stenosis based on multiple independent risk factors. The aim of the study was to improve the accuracy of detection. First, we searched the existing literature to identify multiple independent risk factors and then calculated the corresponding odds ratios. The improved analytic hierarchy process (IAHP) was then used to determine the weighted value of each independent risk factor, based on the corresponding odds ratio. Next, we developed a novel method, based on the top seven independent risk factors with the highest weighted values, to predict FFR. This model was then used to predict the FFR of 253 patients with coronary stenosis, and the results were then compared with previous methods (DS alone and a simplified scoring system). In addition to DS, we identified a range of other independent risk factors, with the highest weighted values, for predicting FFR, including gender, body mass index, location of stenosis, type of coronary artery distribution, left ventricular ejection fraction, and left myocardial mass. The area under the receiver-operating characteristic curve (AUC) for the newly developed method was 84.3% (95% CI: 79.2–89.4%), which was larger than 65.3% (95% CI: 61.5–69.1%) of DS alone and 74.8% (95% CI: 68.4–81.2%) of the existing simplified scoring system. The newly developed method, based on multiple independent risk factors, effectively improves the prediction accuracy for FFR.

Usefulness of Stress-Derived E/e' Ratio in Asymptomatic Hypertensive Patients

Purpose

We sought to investigate the usefulness of stress echocardiography-derived E/e' in predicting subclinical atherosclerosis in asymptomatic hypertensive patients.

Materials and Methods

71 newly diagnosed untreated hypertensive patients (48 ± 13 years, 65% males) and 30 age- and sex-matched healthy controls were recruited. Resting and exercise echocardiography was performed to assess resting diastolic blood pressure and the diastolic stress parameters. Coronary flow reserve (CFR) was evaluated as well.

Results

Based on CFR values, newly diagnosed, untreated hypertensives were stratified into hypertensives with microvascular dysfunction (MVD; 34 patients had CFR <2.0) and those without MVD (37 patients had CFR ≥2.0). Patients with MVD had a significantly higher C-reactive protein level (p < 0.05) and lower metabolic equivalent values (p < 0.05). With resting echocardiography, only the left atrial volume index (LAVI) was significantly increased in those with MVD compared with those without MVD and controls (p < 0.05). With exercise echo, the E/e' was significantly increased in MVD patients compared with those without MVD and controls (p < 0.001). Importantly, the percentage of subjects with exercise E/e' ≥15 was 76.5% (26 patients in the group with MVD), 4.1% (3 patients in the group without MVD), and 0% in controls. At univariate analysis, high-sensitivity C-reactive protein (p < 0.05), LAVI (p < 0.05), and exercise E/e' (p < 0.001) were independently associated with reduced CFR. On the other hand, at multivariate analysis, only exercise E/e' was the independent predictor of reduced CFR in newly diagnosed hypertensives.

Conclusion

We have demonstrated significant associations between exercise-derived raised left ventricular pressure and coronary MVD in newly diagnosed untreated hypertensive patients. Herein, we supposed that exercise-derived E/e' could predict subclinical atherosclerosis and might be a risk parameter for newly diagnosed untreated hypertensive patients.

Independence of coronary artery disease to subclinical left ventricular dysfunction

OBJECTIVE

Epicardial atherosclerosis and heart failure while distinct clinical entities share common pathophysiological features including endothelial dysfunction and inflammation. Presence of subclinical disease could lead to early diagnosis and intervention in the other. The aim of our study was to assess the association between coronary calcium score (CCS), conventional cardiovascular risk factors, and echocardiographic markers of subclinical left ventricular dysfunction (S-LVD).

METHODS

One hundred and fifty-nine participants aged 40-70 years with intermediate risk of coronary artery disease (5-year risk of 2%-15%) were identified. Computed tomography (CT) CCS and 2-D transthoracic echocardiography were performed. Main outcomes included presence of subclinical left ventricular dysfunction defined by reduced average global longitudinal strain, left atrial volume enlargement, and elevated E/e'.

RESULTS

Fifteen participants had evidence of subclinical LV dysfunction (8 with systolic dysfunction and 7 with diastolic dysfunction) and 85 participants had CCS > 0. CCS > 0 was present in 10 participants with S-LVD compared to 75 participants without S-LVD (67% vs 53%, P = .47). There was no significant difference between in mean GLS (19.2 vs 19.5, P = .14), E/e' (7.2 vs 7.5 P = .33) in those without or with coronary artery calcium. Elevated CCS was also not associated with a higher tertiles of indexed LV mass (OR 1.15, P = .49) or index left atrial volume (OR 1.15, P = .49).

CONCLUSIONS

In an asymptomatic, low-intermediate-risk group, mechanistic processes that lead to atherosclerosis are not directly associated with subclinical LV dysfunction.

Impaired coronary microcirculation is associated with left ventricular diastolic dysfunction in end-stage chronic kidney disease patients

INTRODUCTION

Coronary vascular dysfunction, as assessed by coronary flow reserve (CFR) in the left anterior descending coronary artery, is found in various conditions including end-stage chronic kidney disease (CKD). Currently, we investigated the associations of CFR with echocardiographic indices of systolic and diastolic cardiac function and identified independent predictors of CFR in hemodialysis patients.

METHODS

End-stage CKD patients treated with hemodialysis (n = 29) without known cardiovascular disease were recruited from a Hemodialysis Unit in Northwestern Greece. A thorough echocardiographic evaluation including CFR measurement following dipyridamole infusion was performed in all participants. Arterial stiffness was assessed by measurement of carotid-femoral pulse wave velocity and aortic augmentation index.

RESULTS

The mean age of the patients was 63 years, and mean duration of hemodialysis was 2.9 years. CFR was 1.60 ± 0.37 while dipyridamole caused a significant increase in E'_sep , S_lat , E'_lat , and Stroke volume (P < .05 for all). Independent predictors of CFR were posterior wall thickness (B -0.408, P = .013) and dipyridamole-induced changes in Tei index (B -0.425, P = .007). A severely decreased CFR < 1.5 was observed in 52% of the patients. E/E' ratio (B 10.84, P = .014) was the single independent predictor of severely decreased CFR.

CONCLUSIONS

In end-stage CKD patients on hemodialysis without known cardiovascular disease, impaired coronary vascular function was prevalent and related to increased left ventricular wall thickness, increased filling pressures, and dipyridamole-induced deteriorated myocardial function independently of the presence of wall-motion abnormalities. Further studies are required to clarify the prognostic role of dipyridamole-induced cardiac changes in hemodialysis patients.

Overlap between angina without obstructive coronary artery disease and left ventricular diastolic dysfunction with preserved ejection fraction

Background

A link between angina with no obstructive coronary artery disease (CAD) and heart failure with preserved left ventricular ejection fraction has been proposed, but evidence in support of this is lacking. In a cross-sectional study, we investigated whether left ventricular diastolic function in women with angina pectoris and no obstructive CAD differed from a reference population.

Methods

We included 956 women with angina and <50% coronary artery stenosis at invasive coronary angiography. Women with cardiovascular risk factors, but no history of chest pain or cardiac disease served as controls (n = 214). Left ventricular diastolic function was assessed by transthoracic echocardiography.

Results

The women with angina were slightly older, had higher body mass index, higher heart rate, and more had diabetes compared with controls while systolic blood pressure was lower. In age-adjusted analyses, angina patients had significantly lower E/A (Estimated difference -0.13, 95% CI: -0.17; -0.08), higher left ventricular mass index (5.73 g/m², 95% CI: 3.71; 7.75), left atrial volume index (2.34 ml/m², 95% CI: 1.23; 3.45) and E/e’ (0.68, 95% CI: 0.30; 1.05) and a larger proportion had higher estimated left ventricular filling pressure (17% versus 6%, p = 0.001). No between group differences were seen for e’ or deceleration time. After adjustment for known cardiovascular risk factors, between group differences for echocardiographic parameters remained statistically significant.

Conclusions

Patients with angina and no obstructive CAD had a more impaired left ventricular diastolic function compared with an asymptomatic reference population. This suggests some common pathophysiological pathway between the two syndromes.

Physical training improves myocardial perfusion but not left ventricular function response to exercise in patients with microvascular angina

BACKGROUND

Patients with primary microvascular angina (PMA) commonly exhibit abnormal left ventricular function (LVF) during exercise, potentially owing to myocardial ischemia. Herein, we investigated in PMA patients the effect of the reduction of myocardial perfusion disorders, by using aerobic physical training, upon LVF response to exercise.

METHODS

Overall, 15 patients (mean age, 53.7±8.9 years) with PMA and 15 healthy controls (mean age, 51.0±9.4 years) were studied. All subjects were subjected to baseline resting and exercise ventriculography, myocardial perfusion scintigraphy (MPS), and cardiopulmonary testing. PMA group members then participated in a 4-month physical training program and were reevaluated via the same methods applied at baseline.

RESULTS

Baseline left ventricular ejection fraction (LVEF) determinations by ventriculography were similar for both groups (PMA, 67.7±10.2%; controls, 66.5±5.4%; P=0.67). However, a significant rise in LVEF seen in control subjects during exercise (75.3±6.2%; P=0.0001) did not materialize during peak exercise in patients with PMA (67.7±10.2%; P=0.47). Of the 12 patients in the PMA group who completed the training program, 10 showed a significant reduction in reversible perfusion defects during MPS. Nevertheless, LVEF at rest (63.5±8.7%) and at peak exercise (67.3±15.9%) did not differ significantly (P=0.30) in this subset.

CONCLUSIONS

In patients with PMA, reduced left ventricular inotropic reserve observed during exercise did not normalize after improving myocardial perfusion through aerobic physical training.

Effect of diabetes and metabolic syndrome on myocardial mechano-energetic efficiency in hypertensive patients. The Campania Salute Network

Reduced myocardial mechano-energetic efficiency (MEE), estimated as stroke volume/heart rate ratio per g of left ventricular (LV) mass (LVM), and expressed in μl s^-1 g^-1 (MEEi), is a strong predictor of cardiovascular (CV) events, independently of LV hypertrophy and other confounders, including type II diabetes (DM). Decreased MEEi is more frequent in patients with diabetes. In the present analysis we evaluated the interrelation among MEEi, DM and metabolic syndrome (MetS) in the setting of arterial hypertension. Hypertensive patients from the Campania Salute Network, free of prevalent CV disease and with ejection fraction >50% (n=12 503), were analysed. Coexistence of MetS and DM was ordinally categorized into 4 groups: 8235 patients with neither MetS nor DM (MetS-/DM-); 502 without MetS and with DM (MetS-/DM+); 3045 with MetS and without DM (MetS+/DM-); and 721 with MetS and DM (MetS+/DM+). After controlling for sex, systolic blood pressure, body mass index, relative wall thickness (RWT), antihypertensive medications and type of antidiabetic therapy, MEEi was 333 μl s^-1 g^-1 in MetS-/DM-, 328 in MetS-/DM+, 326 in MetS+/DM- and 319 in MetS+/DM+ (P for trend <0.0001). In pairwise comparisons (Sidak-adjusted), all conditions, except MetS-/DM+, were significantly different from MetS-/DM- (all P<0.02). No statistical difference was detected between MetS-/DM+ and MetS+/DM-. Both MetS and DM are associated with decreased MEEi in hypertensive patients, independently to each other, but the reduction is statistically less evident for MetS-/DM+. MetS+/DM+ patients have the lowest levels of MEEi, consistent with the alterations of energy supply associated with the combination of insulin resistance with insulin deficiency.

Glucagon-like peptide-1 protects against ischemic left ventricular dysfunction during hyperglycemia in patients with coronary artery disease and type 2 diabetes mellitus

Background

Enhancement of myocardial glucose uptake may reduce fatty acid oxidation and improve tolerance to ischemia. Hyperglycemia, in association with hyperinsulinemia, stimulates this metabolic change but may have deleterious effects on left ventricular (LV) function. The incretin hormone, glucagon-like peptide-1 (GLP-1), also has favorable cardiovascular effects, and has emerged as an alternative method of altering myocardial substrate utilization. In patients with coronary artery disease (CAD), we investigated: (1) the effect of a hyperinsulinemic hyperglycemic clamp (HHC) on myocardial performance during dobutamine stress echocardiography (DSE), and (2) whether an infusion of GLP-1(7-36) at the time of HHC protects against ischemic LV dysfunction during DSE in patients with type 2 diabetes mellitus (T2DM).

Methods

In study 1, twelve patients underwent two DSEs with tissue Doppler imaging (TDI)—one during the steady-state phase of a HHC. In study 2, ten patients with T2DM underwent two DSEs with TDI during the steady-state phase of a HHC. GLP-1(7-36) was infused intravenously at 1.2 pmol/kg/min during one of the scans. In both studies, global LV function was assessed by ejection fraction and mitral annular systolic velocity, and regional wall LV function was assessed using peak systolic velocity, strain and strain rate from 12 paired non-apical segments.

Results

In study 1, the HHC (compared with control) increased glucose (13.0 ± 1.9 versus 4.8 ± 0.5 mmol/l, p < 0.0001) and insulin (1,212 ± 514 versus 114 ± 47 pmol/l, p = 0.01) concentrations, and reduced FFA levels (249 ± 175 versus 1,001 ± 333 μmol/l, p < 0.0001), but had no net effect on either global or regional LV function. In study 2, GLP-1 enhanced both global (ejection fraction, 77.5 ± 5.0 versus 71.3 ± 4.3%, p = 0.004) and regional (peak systolic strain −18.1 ± 6.6 versus −15.5 ± 5.4%, p < 0.0001) myocardial performance at peak stress and at 30 min recovery. These effects were predominantly driven by a reduction in contractile dysfunction in regions subject to demand ischemia.

Conclusions

In patients with CAD, hyperinsulinemic hyperglycemia has a neutral effect on LV function during DSE. However, GLP-1 at the time of hyperglycemia improves myocardial tolerance to demand ischemia in patients with T2DM.

Trial Registration: http://www.isrctn.org. Unique identifier ISRCTN69686930

Coronary microvascular function is independently associated with left ventricular filling pressure in patients with type 2 diabetes mellitus

BACKGROUND

Left ventricular (LV) diastolic dysfunction is known as an early marker of myocardial alterations in patients with diabetes. Because microvascular disease has been regarded as an important cause of heart failure or diastolic dysfunction in diabetic patients, we tested the hypothesis that coronary flow reserve (CFR), which reflects coronary microvascular function, is associated with LV diastolic dysfunction in patients with type 2 diabetes.

METHODS

We studied asymptomatic patients with type 2 diabetes but without overt heart failure. Transthoracic Doppler echocardiography was performed that included pulsed tissue Doppler of the mitral annulus and CFR of the left anterior descending artery (induced by adenosine 0.14 mg/kg/min). The ratio of mitral velocity to early diastolic velocity of the mitral annulus (E/e') was used as a surrogate marker of diastolic function. We also evaluated renal function, lipid profile, parameters of glycemic control and other clinical characteristics to determine their association with E/e'. Patients with LV ejection fraction <50%, atrial fibrillation, valvular disease, regional wall motion abnormality, renal failure (serum creatinine >2.0 mg/dl) or type 1 diabetes were excluded. Patients with a CFR <2.0 were also excluded based on the suspicion of significant coronary artery stenosis.

RESULTS

We included 67 asymptomatic patients with type 2 diabetes and 14 non-diabetic controls in the final study population. In univariate analysis, age, presence of hypertension, LV mass index, estimated glomerular filtration rate and CFR were significantly associated with E/e'. Multivariate analysis indicated that both LV mass index and CFR were independently associated with E/e'. In contrast, there were no significant associations between parameters of glycemic control and E/e'.

CONCLUSIONS

CFR was associated with LV filling pressure in patients with type 2 diabetes. This result suggests a possible link between coronary microvascular disease and LV diastolic function in these subjects.

Characteristics of Patients With Diabetes Having Normal Coronary Arteries

We evaluated the association between risk variables in diabetic patients with normal and diseased coronary arteries in a retrospective cohort study conducted at Rashid Hospital, Dubai. A total of 4446 patients underwent coronary angiography due to various indications; 43% had type 2 diabetes mellitus (T2DM). Among the diabetic patients, 94% had diseased coronary arteries and the remaining 6% had absolutely normal arteries. The normal coronary group had significantly lower low-density lipoprotein cholesterol (LDL-C) and a higher high-density lipoprotein cholesterol (HDL-C) levels than the diseased group. Patients with normal coronaries were more likely to be females, have T2DM for a shorter duration, and were nonsmokers and non-South Asians. They also had lower levels of LDL, hemoglobin A1c, and fasting glucose and higher levels of HDL-C. Apart from these variables, genetic or environmental factors could protect these patients from atherosclerosis.

Time-course changes in left ventricular myocardial deformation in STZ-induced rabbits on velocity vector imaging

OBJECTIVES

To clarify the time-course changes in left ventricular myocardial deformation using velocity vector imaging and to provide insights into our understanding of the cardiac pathophysiology in diabetes mellitus.

METHODS

Thirty New Zealand white rabbits were randomly divided into either the control group (n = 10) or the diabetes mellitus (DM) group (induced with STZ, n = 20). For the myocardial deformation studies, echocardiography and syngo-vector velocity imaging (VVI) were performed at baseline and after 2, 4, 8, and 12 weeks in all of the rabbits. The left ventricular (LV) global longitudinal and circumferential strain and strain rate were measured. For histomorphological study of the heart structure, 2 of the STZ-induced rabbits were killed at 2, 4, 8, and 12 weeks. Routine hematoxylin and eosin staining was performed.

RESULTS

At 2 weeks, the global longitudinal strain (GLS), systolic strain rate (GLSRs), and diastolic strain rate (GLSRd) were significantly lower in the DM group compared with the control group (-18.16% versus -24.00%, -1.86 s(-1) versus -2.49 s(-1), 1.93 s(-1) versus 2.42 s(-1), respectively, P < 0.05), while, compared with the control group, the global circumferential strain (GCS), systolic strain rate (GCSRs), and diastolic strain rate (GCSRd) in the DM group were significantly decreased (-12.77% versus -23.31%, -1.31 s(-1) versus -2.20 s(-1), 1.41 s(-1) versus 2.15 s(-1), respectively, P < 0.05) at 8 weeks. With the progression of untreated diabetes, the histoanatomical alterations intensified gradually beginning at 2 weeks.

CONCLUSIONS

The progressive impairments in LV myocardial deformation and structure occurred early in diabetic rabbits with normal LV ejection fraction (EF), FS, and E/A. VVI could be used to evaluate subtle cardiac dysfunction in the early phase of DM.

Impaired resting myocardial annular velocities are independently associated with mental stress-induced ischemia in coronary heart disease

OBJECTIVES

The aim of this study was to investigate the association between resting myocardial function as assessed by tissue Doppler myocardial velocities and the propensity to develop mental stress-induced ischemia (MSIMI).

BACKGROUND

Tissue Doppler myocardial velocities detect preclinical cardiac dysfunction and clinical outcomes in a range of conditions. However, little is known about the interrelationship between myocardial velocities and the propensity to develop MSIMI compared with exercise stress-induced myocardial ischemia.

METHODS

Resting annular myocardial tissue Doppler velocities were obtained in 225 patients with known coronary heart disease who were subjected to both conventional exercise stress testing as well as a battery of 3 mental stress tests. Diastolic early (e') and late (a') as well as systolic (s') velocities were obtained, and the eas index, an integrated measure of myocardial velocities, was calculated as e'/(a' × s'). MSIMI was defined as: 1) the development or worsening of regional wall motion abnormality; 2) a reduction in left ventricular ejection fraction ≥ 8%; and/or 3) ischemic ST-segment changes during 1 or more of the 3 mental stress tests.

RESULTS

A total of 98 of 225 patients (43.7%) exhibited MSIMI. Patients developing MSIMI had significantly lower s' (7.0 ± 1.7 vs. 7.5 ± 1.2, p = 0.016) and a' (8.9 ± 1.8 vs. 10.0 ± 1.9, p < 0.001) at baseline, whereas e' did not differ (6.5 ± 1.7 vs. 6.5 ± 1.8, p = 0.85). Furthermore, the eas index was significantly higher (0.11 ± 0.04 vs. 0.09 ± 0.03, p < 0.0001). The eas index remained significantly associated with the propensity to develop MSIMI (odds ratio per 0.05-U increase: 1.85; 95% confidence interval: 1.21 to 2.82; p = 0.004) after adjustment for resting left ventricular ejection fraction, resting wall motion index score, sex, and social circumstances of living. There was no association between resting eas index and exercise stress-induced myocardial ischemia.

CONCLUSIONS

MSIMI but not exercise stress-induced myocardial ischemia is independently associated with resting abnormalities in myocardial systolic and late diastolic velocities as well as the integrated measure of the eas index in patients with known coronary artery disease. (Responses of Myocardial Ischemia to Escitalopram Treatment [REMIT]; NCT00574847).

Coronary flow reserve is associated with tissue ischemia and is an additive predictor of intensive care unit mortality to traditional risk scores in septic shock

BACKGROUND

Reduced coronary velocity flow reserve (CFR) is associated with poor outcome in patients with cardiovascular disease. We investigated whether CFR is associated with tissue ischemia and acidosis, impaired myocardial deformation and adverse outcome in patients with septic shock.

METHODS

In 70 mechanically-ventilated patients with septic shock, we examined: a) S' and E' mitral annular velocities using tissue Doppler imaging (TDI), b) CFR of the left anterior descending artery after adenosine infusion using transesophageal Doppler echocardiography and c) lactate, pyruvate and glycerol in tissue by means of a microdialysis (MD) catheter inserted into the subcutaneous adipose tissue as markers of tissue ischemia and acidosis. SOFA and APACHE II prognostic scores and mortality in the intensive care unit (ICU) were recorded.

RESULTS

Reduced CFR, S' and E' as well as increased E/E' correlated with increased SOFA, APACHE II and MD lactate to pyruvate ratio (p<0.05 for all correlations). Impaired TDI markers also correlated with increased MD glycerol (p<0.05). Reduced CFR correlated with decreased E' (p<0.05). CFR was 1.8 ± 0.42 in non-survivors (n=34) versus 2.08 ± 0.44 in survivors (p=0.007). A CFR<1.90 predicted mortality with sensitivity of 70% and specificity of 69% (area under the curve 77%; p=0.003). CFR had an additive value to APACHE (chi-square change: 4.358, p=0.03) and SOFA (chi-square change: 3.692, p=0.04) for the prediction of mortality.

CONCLUSION

Tissue ischemia and acidosis is a common pathophysiological link between decreased CFR and impaired LV myocardial deformation in septic shock. CFR is an additive predictor of ICU mortality to traditional risk scores in septic shock.