Prediction of atrial fibrillation in patients with mitral stenosis: role of atrial septal motion vekocity

The most important proximate cause of atrial fibrillation [AF] in mitral stenosis [MS] is left atrial[LA] dysfunction, so several studies concerned with LA function assessment - body and appendage- have been undertaken. However, inter atrial septum has not been evaluated in MS. The present study was designed to detect atrial septal motion velocity [ASMV] using Doppler tissue echocardiography in MS patients and to investigate the possible role of ASMV in predicting development of AF in MS. Sixty six MS patients were evaluated by transthoracic echocardiography as well as transesophageal echocardiography where ASMV were recorded by triggering tissue Doppler mode. Patients were divided according to rhythm status and ASMV display. The studied patients displayed 2 characteristic patterns of ASMV, the first pattern showed positive wave at late diastole [D], followed by biphasic waves[+ve and -ye B 1] and negative wave at systole [S] that followed again by biphasic waves[+ve and -ye B2]. All patients with this pattern were in sinus rhythm[SR] and considered as group I. The second pattern was lacking B 2 12 patients with this pattern were in SR and categorized as group II while 33 patients were in AF and categorized as group III. LA dilatation, frequency of LA spontaneous echo contrast and reduced ASMV were increasing from group I to group III. Small MVA and absent B2 Were matched in groups II and III, so group II appeared as transition from group I to group III. Reduced ASMV especially negative waves [S and -ye B[1]] were sensitive and specific predictors for AF especially a bsent B2 which had 100% sensitivity [positive predictive value 100%] and specificity [negative predictive value 100%] for AF prediction. Absence of B2 waves and reduction of other ASMV waves can be used to identify MS patients prone to develop AF with high sensitivity and specificity. These changes appear as preclinical loss in ASMV before the onset of AF

QRS duration in isolated left bundle branch block: a marker of ventricular remodling and septal hypoperfusion

Isolated left bundle branch block [LBBB] per se may compromise cardiac mechanics and perfusion; this may contribute to the unfavorable outcome of such patients. The relation of QRS duration in isolated LBBB with cardiac function and perfusion is unknown. So, we sought to evaluate the left ventricular [LV] function and myocardial perfusion in isolated LBBB in relation to QRS duration. The study included 30 patients with isolated LBBB and 10 age and gender matched subjects without conduction delay. All study population had normal coronary angiogram. LBBB patients were divided into group I [17 patients] with 120/=140 msec. LV end diastolic dimension [LVED], LV end systolic dimension [LVES], septal wall thickness [SWT], posterior wall thickness [PWT] and LV ejection fraction [LVEF] were detected by echocardiography and myocardial perfusion was assessed by Thallium-201 [[201]Th] scintigraphy. LV remodeling [as detected from increased LVSD and PWT and decreased LVEF] and septal hypoperfusion [as detected by 201Th scintigraphy] were more frequent in group II [patients with QRS>140 msec]. QRS as it correlated positively with LVES [r 0.79, p<0.001] and negatively with LVEF [r-0.56, p<0.002], it also showed good agreement with myocardial perfusion imaging, the prolonged QRS the more frequent septal hypoperfusion. Moreover, there was a relation between cardiac function and myocardial perfusion in LBBB patients as these patients with perfusion defects showed increased LVES and SWT and decreased LVEF versus those without perfusion defects suggesting that there is link between cardiac function and myocardial perfusion in LBBB. Electrocardiography is commonly used as the first assessment tool for possible cardiac disease. QRS duration in patients with isolated LBBB is closely related to LV remodeling and septal hypoperfusion

Differentiation between transmural and non transmural myocardial infarction using tissue doppler imaging

The natural history and outcome of transmural [TM] and nontransmural myocardial infarction [N TM MI] was known to be significantly different many years ago. However, Neither M-mode nor 2-D Echocardiography can provide information regarding TM distribution of contractile performance. Tissue Doppler Echocardiography [TDE] provides new indices of myocardial functions such as myocardial velocity gradient [MVG] which was found to be an accurate method in the experimental assessment of TM. and N. TM. MI. The present work aims to study myocardial velocities in subendocardial and epicardial layers of the infarct segments by pulsed wave [PW] and tissue Doppler echocardiography in order to investigate the value of systolic and diastolic myocardial velocity gradient in distinguishing transmural myocardial infractions from nontransmural one. Forty patients with first attack acute myocardial infarction [MI] and significant single coronary artery disease [> 70% stenosis] were studied with conventional clinical assessment and trans thoracic Echocardiography [TTE] to assess systolic and diastolic left ventricular function, wall motion abnormalities and tissue Doppler imaging [TDI] parameters for assessment of myocardial velocities [including systolic, diastolic and myocardial velocity gradient] in the epicardial and endocardial layers of myocardium. We found a statistically significant difference in the TDI parameters in the endocardial area between the normal and the infarcted segments in patients with transmural and non transmural myocardial infarction. While in the epicardial area there is a statistical significant difference between the infarcted and the normal segments in patients with Q wave myocardial infarction but there is no significant difference in patients with non Q wave myocardial infarction. This means that TDI can detect the non-uniformity of transmural velocity denoting the presence of viable part [epicardial area] in the hypokinetic segments in the nontransmural myocardial infarction. We also found that there is significant difference in TDI parameters in the infarcted segments [either endocardial or epicardial area] between both groups with more depression of the myocardioal velocity in group I [with non Q wave myocardial infarction]. This could be explained by the presence of more viable myocardium in the area with non transmural infarction with less affection of the velocity. We conclude that TDE might be an applicable and noninvasive modality that can detect the non uniformity of transmural velocity differentiating between transmural and nontransmural MI suggesting that aggressive approaches should be taken to salvage myocardium in such patient

Detection of significant left coronary artery stenosis by reduced transthoracic coronary sinus flow reserve

Currently available methods for measurement of coronary flow reserve are invasive, time consuming and need laboratory equipment and staff. So, the aim of this study was to demonstrate coronary sinus flow by transthoracic echocardiography and to determine the feasibility of using CSFR for the diagnosis of left coronary artery stenosis. This study comprised two groups; patients group which consisted of 30 patients with angiographically proven isolated LCA stenosis, and control group which consisted of 10 healthy volunteers. All patients and subjects were examined by echo Doppler to measure coronary sinus diameter and coronary sinus flow dynamics at baseline and again at peak dipyridamole infusion. CSFR was measured by both peak and volumetric methods. At baseline, the coronary sinus diameter and Doppler parameters showed insignificant difference between both groups [P> 0.05]. At peak dipyridamole, a significant increase in CS diameter was seen in both groups [P< 0.01] without significant difference in between [P > 0.05]. However, dipyridamole induced increase of velocity and volume characteristic of CS was marked in control group than in patients group [P< 0.001]. CSFRp and CSFRv showed a highly significant decrease in patients group than control group [P<0.001]. CSFR by peak or volumetric methods

Regional left atrial contractility in patients with isolated mitral stenosis

The study comprised 39 patients of MS and 10 normal control subjects. 15 patients were sinus rhythm [SR] and NYHA class I [group I], 12 patients were SR and NYHA class II [group II] and 12 patients were atrial fibrillation [AF] and NYHA class II [group III]. LA body emptying fraction [EFLA] was calculated echocardiographically as LA maximal volume-LA minimal volume x100/LA maximal volume. LA appendage [LAA] function was assessed by transesophageal echo-Doppler study to obtain the maximal and minimal LAA sizes, LAA emptying fraction [EFLAA] and LAA emptying flow velocity [LAA.A]. Results showed that EFLA was decreasing in patients groups in the following order: Group I, group II and group III. The LAA systolic function of group I was comparable to that of control, while it was significantly decreased in group II in manner similar to but less severe than group III. LAA systolic function was inversely related to age of patients, LAA size and directly related to mitral valve area. Ejection fraction of left ventricle [LV] correlated best with EFLAA