1/6. Myocardial perfusion and metabolic changes induced by biventricular pacing in dilated cardiomyopathy and left bundle branch block: description of a case evaluated by positron emission tomography.The effects of biventricular pacing on myocardial wall function are well known, but, at the moment, its real effects on myocardial metabolism are unclear. In patients affected by left bundle branch block, at positron emission tomography a septal defect of the uptake of 18F-fluorodeoxyglucose (FDG) was referred. There were no alterations in myocardial perfusion, suggesting possible metabolic damage. In this paper we report the case of a patient affected by dilated cardiomyopathy and left bundle branch block treated with a biventricular device. Biventricular pacing resolved both the wall motion alterations as well as the defect in FDG uptake present in the septal area. On the contrary, during biventricular pacing there were no modifications in myocardial perfusion as compared to basal evaluation.- - - - - - - - - - ranking = 1keywords = motion (Clic here for more details about this article) |
2/6. The use of echocardiographic colour kinetic wall motion to differentiate broad complex tachycardia.Discrimination between supraventricular tachycardia (SVT) with aberrant conduction from ventricular tachycardia (VT) is vital for the safe and effective management of both conditions. Electrocardiographic algorithms for the differentiation of broad complex tachycardia are complex and difficult to implement in the acute setting, with misdiagnosis occurring in up to 40% of acute presentations. This case study shows the potential for echocardiographic colour kinesis (eck) to support electrocardiographic differentiation. A 74-year old man in sinus rhythm with left bundle branch block (lbbb), a history of myocardial infarction and recurrent sustained VT underwent eck analysis of wall motion propagation during a programmed electrical ventricular stimulation study. Sequential 40 ms time frames of echocardiographic colour coded endocardial wall motion velocity were recorded on video during both induced VT of lbbb configuration and near isochronic atrially paced tachycardia in lbbb. During VT there was initial eck propagation of ventricular septal wall motion from the apex to the atria secondary to electrical depolarisation. During atrially paced tachycardia initial eck motion developed in the interatrial septum and atrial wall followed by propagation in the ventricular endocardial septal wall motion from the atria toward the ventricular apex. This eck technique potentially could be used to support the electrocardiographic diagnosis of a broad complex tachycardia.- - - - - - - - - - ranking = 9keywords = motion (Clic here for more details about this article) |
3/6. Asymptomatic brugada syndrome case unmasked during dimenhydrinate infusion.Typical ECG of that described for brugada syndrome was elicited in a patient diagnosed with labyrinthopathy during infusion of dimenhydrinate, a first-generation antihistamine usually used to treat motion sickness. Although the patient had no history of syncope or palpitations, and there was no family history of cardiac disease or sudden death, the ECG abnormality was reproduced later with intravenous flecainide, and an asymptomatic brugada syndrome was diagnosed.- - - - - - - - - - ranking = 1keywords = motion (Clic here for more details about this article) |
4/6. Phase quadrature shift between left and right ventricles during a ventricular tachycardia attack.Equilibrium gated nuclear angiography was performed on a patient during an attack of ventricular tachycardia and then after conversion to sinus rhythm. Global and regional wall motion was assessed by means of isocontours, Fourier phase analysis and factor analysis. Ventricular phase histograms showed a 100 degrees difference between ventricles: left ventricular filling time occurred during right ventricular contraction. The earliest phase was located in the septum and the sequence of activation showed a large delay of left ventricular activation. After conversion to sinus rhythm, a right bundle branch block was observed, being almost the inverse of the latter situation.- - - - - - - - - - ranking = 1keywords = motion (Clic here for more details about this article) |
5/6. Sequential regional phase mapping of radionuclide gated biventriculograms in patients with sustained ventricular tachycardia: close correlation with electrophysiologic characteristics.Radionuclide (rna) gated studies were performed during sinus rhythm and during spontaneous or induced sustained ventricular tachycardia (VT) in six patients with clinical VT. fourier analysis of time-activity variation was used to calculate a rna phase value for each pixel in the image. color coding of each pixel according to its calculated phase resulted in a rna phase map of the ventricles. The following results were considered to be consistent with the known electrophysiology of VT: (1) the phase map correlated with QRS morphology and axis in most but not all tachycardias; (2) earliest phase usually demonstrated the VT origin to be at the border of the ventricular wall motion abnormality; (3) endocardial mapping (available in one patient) showed close correlation with rna phase mapping; (4) in three patients with ischemic heart disease, VT with left bundle branch block (LBBB) pattern had earliest LV phase along the septum; and (5) for one patient imaged during two different VT morphologies, the tachycardias had earliest phase at different borders of the same wall motion abnormality with differing progression of phase across the ventricles. rna phase mapping of VT is feasible and appears to provide data consistent with the electrophysiology of this arrhythmia.- - - - - - - - - - ranking = 2keywords = motion (Clic here for more details about this article) |
6/6. Effects of intermittent left bundle branch block on left ventricular diastolic function: a case report.We investigated systolic and diastolic left ventricular function in a patient with an echocardiographically normal left ventricle and rate dependent left bundle branch block. Abnormal activation was associated with asynchronous left ventricular wall motion and secondary changes in filling pattern. The latter were similar to those seen in severe left ventricular disease. When the activation pattern reverted to normal, all of these abnormalities regressed. This case provides further evidence that abnormal activation can, on its own, cause left ventricular diastolic as well as systolic dysfunction.- - - - - - - - - - ranking = 1keywords = motion (Clic here for more details about this article) |