Transesopnageal echocardiographic anatomical and functional assessment of right atrial appendage: comparison with left atrial appendage and implications for local thrombus formation in patients with mitral stenosis

Right atrial appendage [RAA] thrombi and dysfunction have been reported in patients with atrial fibrillation [AF]. Although pulmonary embolism was a life-threatening complication of AF, there are little data about RAA and its thrombi in AF. Furthermore, to date there have been no prospective studies designed to examine RAA in patients with rheumatic mitral stenosis [MS]. To define RAA anatomical and functional parameters and to compare them with left atrial appendage [LAA] parameters in patients with moderate MS both in AF and in sinus rhythm [SR] and to study the implications for local thrombus formation. Transthoracic [TTE] and multiplane transesophageal echo [TEE] were performed in 31 patients with moderate MS [16 in SR. Group I and 15 in AF, Group II]. We measured mitral valve area [MVA], mean pulmonary artery pressure [MPAP], left atrial diameter [LAD], LV EDD and ESD, EF%, RAA and LAA neck width, length, area, ratio of neck to area, and emptying velocity. We assessed also the incidence of RA-RAA and LALAA SEC and thrombi. Adequate visualization of RAA was highly feasible by TEE in 31/34 [91%] of patients. RAA anatomic and functional parameters were independent of imaging plane. Patients in AF had significantly increased LAD [p=0.004] and MPAP [p<0.0001] than those in SR. The RAA area was proportional to the LAA area [r=0.87, p<0.0001] only in patients with SR. On the other hand, RAA neck width and ratio of neck width to area were greater than those of LAA while LAA length and area were greater than those of RAA regardless the presence of AF. AF caused more enlargement in LAA [10.21 +/- 4.15 Vs 5.41 +/- 1.78, p<0.0001] compared to RAA [5.37 +/- 2.08 Vs 4.40 +/- 1.44, p=NS] while more dysfunction in RAA / [reduced emptying velocities [0.45 +/- 0.11]-[0.28 +/- 0.08], [40%] p<0.0001] compared to that of the LAA [0.43 +/- 0.08] - [0.32 +/- 0.14], [25.6%] p<0.01/ ]. AF caused higher prevalence of RAA spontaneous echo contrast [SEC] [66.7%] than in SR [37.5%], [p<0.0001]. Also it caused higher RAA thrombosis [46.7%] than in SR [25%], [p=0.001]; and finally RAA SEC was the only independent predictor of RAA thrombosis in SR [p=0.04] while the reduced ejection velocity was the only independent predictor of RAA thrombosis in MS patients with AF [p=0.04]. RAA imaging was highly feasible. RAA anatomic and functional parameters were independent of imaging plane. AF was associated with RAA minimal remodeling, maximal dysfunction and subsequently thrombosis. RAA dysfunction and SEC were independent predictors for RAA thrombosis. RAA SEC and thrombosis were directly proportional to LAA remodeling and dysfunction. Therefore, assessment of not only LAA but also RAA may be important during TEE examination of patients with MS

Tissue doppler echocardiographic assessment of right ventricular function in patients with acute inferior myocardial Infarction

Unlike left ventricular [LV] function, right ventricular [RV] function has not been widely studied after myocardial infarction [RVMI]. Furthermore, rapid, accurate, and widely available non-invasive evaluation of RV function still presents a problem. The purpose of this study was to determine whether parameters derived from tissue Doppler imaging [TDI] of tricuspid annulus could be used to detect RV infarction and so to assess RV function in patients with first acute inferior myocardial infarction [AIMI]. Patients and. We examined 27 patients with first AIMI admitted to CCU at El Minia University Hospital between March 2005 and October 2007, 12 with [group I] and 15 without ECG signs of RVMI [group II]. Twenty adults served as controls [group III]. Patients with any cardiovascular risk factor were excluded. Tissue Doppler Echocardiographic [TDE] study included recording of peak systolic [Sm], early diastolic [Em], late diastolic [Am] and [Em/Am] ratio of tricuspid annular velocities at 2 sites corresponding to the septum and RV free wall from apical 4 chamber view. Ejection time [ET], isovolumic relaxation time [IVRT], and isovolumic contraction time [IVCI'] were also recorded, then, Tie index [MPI] was calculated for each site. Standard echo Doppler study, electrocardiogram [ECG] and cardiac enzymes were also performed. Patients with AIMI had significantly reduced peak Sm, Em, Am and Em/Am ratio and increased IVRT, IVCT, ET and Tei index at the 2 sites especially at the RV free wall [infarction site] compared with healthy controls. At septal side of the tricuspid annulus, the peak Sm, Em, and Am were significantly reduced in group I compared with both group II, p=0.032. p<0.0001, p=0.001 respectively and group Ill, p<0.0001 for all velocities, with slightly significantly reduced velocities in group II compared with controls, p=0.012, 0.016, 0.030 respectively. The Sm/Am ratio was significantly decreased in group I compared with both group II, p<0.0001 and group Ill, p<0.0001 without significant difference between the latter two groups. While, the IVRT, IVCT, and ET were significantly increased in group I compared with both group II, p=0.004, 0.043, 0.005 and group Ill, p<0.0001, 0.0001, 0,026 respectively. Apart from ET, both of IVRT and IVCT were also increased in group II compared with group lII, p=0.03, 0.009. The septal MPI was significantly increased in both group I, p=0.002 and group II, 0.003 compared with controls without difference between both groups. On the other hand, at RV free wall, these myocardial velocities and Em/Am ratio were significantly reduced only in group I compared with both group 11, [p<0.0001 for all, p=0.029 for Em/Am ratio] and group Ill, [p<0.0001 for all, p=0.016 for Em/Am ratio] without significant difference between the latter two groups. While, IVRT, IVCT, ET, and RV MPI were significantly increased also only in group I compared with both group II, p<0.0001 for all and group Ill, p<0.0001 for all, without significant difference between the latter two groups. At Sm cutoff value of <12 cm/s, we were able to detect RVMI by 85% sensitivity, 93% specificity, 92% PPV, and 87% NPV, while at RV MPI >0.7, these were 92%, 100%, 100%, and 93% respectively. Systolic and diastolic myocardial velocities at the tricuspid annulus can be easily and quickly recorded by pulsed wave TDE. The decreased velocities and increased MPI seem to be an expression of regionally reduced myocardial function especially at the RV infarction site and so reflects RV systolic and diastolic dysfunction. Therefore, TDE can be used to assess RV systolic and diastolic function in patients with AIMI

Study of changes in P wave dispersion and duration as predictors of AF in patients with primary dilated cardiomyopathy

Background: P wave duration on signal averaging ECG [PD SAECG] and P wave dispersion [PWD] on standard ECG are non invasive markers of intra-atrial conduction time disturbances, the major electrophysiological cause of atrial fibrillation [AF]. P wave abnormalities have been previously studied in some cardiac conditions, however little data are available in patients with primary dilated cardiomyopathy [DCM]

Objectives: to study changes in PD and PWD as predictors of AF among patients with primary DCM and to correlate these changes with degree of severity of CHF

Patients and Methods: Surface ECG, SAECG and Transthoracic [TTE] echo were performed in 33 patients with primary DCM [Group I] and 30 age and sex matched healthy controls [Group II]. We measured heart rate [HR], minimal p wave [P min], maximal p wave [P max], P wave dispersion [difference between P min and P max = PWD] in surface ECG, P wave duration [PD] in SAECG, Left atrial maximal [LAMX], minimal [LAMN], LA volume at onset of p-wave [LAV p], LA ejection fraction [LA EF], and left ventricular ejection fraction [LV EF] by TTE

Results: There was no significant difference between groups regarding age [42.06 +/- 12.9 Vs 38.5 +/- 10.9, p=0.25] or sex distribution [24/33 [72.7%] Vs 21/30 [70%] males, p=0.81]. Patients with primary DCM showed significantly increased HR, P max and P mm, prolonged PD, and increased PWD, [p<0.0001 for all]. They showed also significantly depressed LV EF and LA EF, with a significantly increased LAMX and LAMN volume, and LAV p, [p<0.0001 for all]. Patients with DCM showed significant positive correlation between PD; and LAMX volume, LAMN volume, and LAVP, [p<0.0001 for all] and significant negative correlation between PD and both LV EF [p<0.0001] and LA EF [p=0.002]. They showed significant positive correlation between PWD; and LAMX, LAMN volume, and LAV p, [p<0.0001] and significant negative correlation between PWD and both LVEF and LAEF [p<0.0001]. Patients with severe DCM [LV EF<25%] showed significantly prolonged P max [p=0.004], P min [p=0.002], PD [p<0.0001] and increased PWD [p=0.004] compared to those with less severe form of the disease [LVER >/= 25%]

Conclusion: The prolonged P-wave duration and increased P-wave dispersion were significantly associated with the increased left atrial volumes, depressed left atrial and left ventricular systolic functions in patients with primary DCM

Predictors of vascular endothelial dysfunction in systemic lupus erythematosus

Vascular endothelium of patients with systemic lupus erythematosus [SLE] after prolonged exposure to circulating immune complexes shows generative changes, which are significant source of mortality and morbidity. To access the endothelial function in patients with SLE and to find the risk factors that may deteriorate that function, three indices of endothelial function were studied including: carotid artery intima/ media thickness, brachial artery diameter and endothelial dependent [EDD] and independent dilatation [EID] of the brachial artery by measuring flow mediated dilatation of the artery before and after sublingual glyceryl trinitrate. Risk factors including: SLE-dependent [disease duration. steroid use, C-reactive protein, double stranded DNA antibody [anti-dsDNA], complement [C3,C4],antibody to Sjogrens syndrome A [SSA[Ro]] and SLE independent [blood pressure, cholesterol, triglycerides, fasting blood sugar, body mass index] were also studied. Thirty women were selected with mean SLE duration was 7.1 +/- 2.6 years, the mean brachial artery diameter was 0.50 +/- 0.03 cm. and the mean carotid artery intima/media thickness was 0.8 +/- 0.03 mm. Our patients with SLE had significantly impaired endothelial dependent dilatation compared with controls. SLE patients show higher incidence of hypertension, hyperlipidemia, thicker carotid intima media thickness and brachial artery diameter. Hypertriglyceridemia, higher levels of C-reactive protein, Anti-dsDNA, SSA [Ro] antibody and lower levels of C3, C4 all are associated with thicker carotid intima/media. Severe degree of SLE is associated with significant decrease in EDD and EID of brachial artery. In conclusion SLE patients are more liable to hypertension, hypertriglyceridemia and hyperglycemia that predisposed to degenerative vascular changes. Longer SLE duration, prolonged steroid use, high fasting blood sugar, high triglycerides, C-reactive protein, antidsDNA, antiSSA [Ro] are strong predictors of endothelial dysfunction. Severe degree of SLE is associated with more impairment in endothelial dependent dilatation and endothelial independent dilatation of brachial artery

Dobutamine-transesophageal echocardiography versus dipyridamole thallium-201 scintigraphy for assessment of myocardial viability

Dipyridamole Thallium-201 scintigraphy have been widely used to differentiate between scar tissue and viable but not functioning myocardium and showed superiority over dobutamine stress echo-cardiography. The development of transesophageal echocardiogram [TEE] may overcome many of transthoracic limitations. To compare dobutamine stress TEE and Dipyridamole thallium scintigraphy in detection of myocardial viability. The study included 27 patients with coronary artery disease [CAD] and severe segmental wall motion abnormalities [SWMA] on resting echocardiogram who were scheduled for revascularization either through angioplasty or bypass surgery [CABG]. Dobutamine-TEE and dipyridamole thallium scintigraphies were done within 5 to 7 days before revascularization. Post-revascularization resting echocardiography was done 14 to 21 days to assess any improvement of SWMA as a sign of myocardial viability. Although the sensitivity of dobutamine TEE to detect myocardial viability was higher than that of thallium scintigraphy [89% vs. 72% respectively] but it did not reach statistical significance [P=0.06]. However, the specificity of TEE was significantly higher than that of scintigraphy [83% vs. 67%, P=0.04] and the total diagnostic accuracy of dobutamine TEE to detect myocardial viability was significantly higher than that of dipyridamole thallium scintigraphy [88% vs. 71% p = 0.05]. In the presence of severe SWMA, dobutamine TEE could detect myocardial viability more frequently than dipyridamole thallium scintigraphy