Modelling the cardiac electrophysiology (EP) can help understand pathologies and predict the response to therapies such as cardiac resynchronization. To this end, estimating patient-specific model parameters is crucial. In the case of patients with bundle branch blocks (BBB), part of the Purkinje system is often affected. The aim of this work is to estimate the activation of the right and left ...

BACKGROUND Left bundle branch block (LBBB) complicates the diagnosis of acute myocardial infarction (AMI). The Sgarbossa criteria were developed from GUSTO I to surmount this diagnostic challenge but have not been prospectively validated in a large population with presumed AMI. We evaluated their utility in the diagnosis and risk stratification of AMI patients in ASSENT 2 & 3. METHODS Baselin...

UNLABELLED Heterogeneous perfusion in left bundle branch block (LBBB) has been demonstrated by (99m)Tc-methoxyisobutylisonitrile (MIBI) SPECT. Locally different contraction is also associated with LBBB. Quantitative analysis of myocardial SPECT is influenced by partial-volume effects depending on systolic wall thickening. Therefore, partial-volume effects may mimic perfusion heterogeneity in LB...

BACKGROUND In Multicenter Automatic Defibrillator Implantation Trial-Cardiac Resynchronization Therapy (MADIT-CRT), patients with non-left bundle branch block (LBBB; including right bundle branch block, intraventricular conduction delay) did not have clinical benefit from cardiac resynchronization therapy with defibrillator (CRT-D). We hypothesized that baseline PR interval modulates clinical r...

UNLABELLED A 78-year-old women with a recent diagnosis of primary hyperparathyroidism presented with vague chest pain, and new onset left bundle block (LBBB) on the electrocardiogram (ECG) mimicking acute myocardial infarction (AMI). LBBB resolved without abnormal Q waves only after correction of hypercalcemia. The cardiac enzymes, including creatine kinase, creatine kinase-MB, and troponin-I w...

Rate-dependent left bundle branch block (LBBB) occasionally occurs during anaesthesia when the heart rate exceeds a critical value. While it is usually a benign disorder, it may mask the electrocardiographic manifestations of myocardial ischaemia and the ST-T wave pattern associated with LBBB may be mistaken for those of ischaemia. This case report presents two cases in which rate-dependent LBB...

Background Left bundle branch block (LBBB) leads to dyssynchronous left ventricular (LV) contraction and relaxation which may contribute to LV dysfunction and ultimately heart failure. LBBB-related mechanical dyssynchrony often responds to cardiac resynchronization therapy (CRT). However, this therapy is expensive and the number of non-responders remains significant. Reliable functional markers...

Cardiac resynchronization therapy (CRT) is associated with a favorable outcome only in patients with left bundle branch block (LBBB) pattern and in patients with a QRS duration > 150 ms, in patients with non-LBBB pattern with a QRS duration of 120-150 ms usually is not beneficial. After adjusting for QRS duration, QRS morphology was no longer a determinant of the clinical response to CRT. In co...

BACKGROUND Ventricular activation is often abnormal in patients with dilated cardiomyopathy, but its specific effects on timing remain undetermined. OBJECTIVE To investigate the use of the ratio of the sum of left ventricular ejection and filling times to the total RR interval (Z ratio) to dissociate the effects of abnormal activation from those of cavity dilatation. METHODS Subjects were 2...