Appearance Of Left Bundle Branch Block Research Articles

New-Onset Left bundle branch block after TAVI has a deleterious impact on left ventricular systolic function

Transcatheter aortic valve implantation (TAVI) has revolutionized the management of severe aortic stenosis. The development of new-onset complete left bundle branch block (LBBB) is, however, a frequent complication. The objective of the present study was to assess the impact of new-onset LBBB after TAVI on the evolution of left ventricular ejection fraction (LVEF). Forty consecutive patients were included following the development of new-onset LBBB after TAVI implantation and were matched for age and LVEF with 40 patients implanted during the same period who did not develop LBBB. The primary endpoint was evolution of the LVEF measured by echocardiography prior to implantation and between 6-12 months after TAVI. The development of a LBBB was associated with a 5-point decrease in LVEF [− 12.5–2.5], contrary to the non-LBBB group (1.5 [− 6.5–9.5], P = 0.007) at 8 months, with the persistence of the LBBB ( n = 23) exacerbating this decrease (− 7 [− 13; 2], P = 0.009). When left ventricular dysfunction (LVEF <50%) was present prior to TAVI, the appearance of LBBB was associated with a reduction in LVEF (− 2 [− 8 – 2]) contrary to the non-LBBB group (20 [9–22]), P = 0.02. The appearance of new-onset LBBB after TAVI has a pejorative impact on left ventricular systolic function, particularly in patients with an initial LVEF < 50%, due to a lack of recovery of the latter, thereby potentially affecting their prognosis.

New-Onset Left Bundle Branch Block After TAVI has a Deleterious Impact on Left Ventricular Systolic Function

BackgroundTranscatheter aortic valve implantation (TAVI) has revolutionized the management of severe aortic stenosis. The development of a new-onset complete left bundle branch block (LBBB) is, however, a frequent complication. The objective of the present study was to assess the impact of a new-onset LBBB after TAVI on the evolution of left ventricular ejection fraction (LVEF). MethodsForty consecutive patients were included after the development of a new-onset LBBB after TAVI and were matched for age and LVEF with 40 patients implanted during the same period who did not develop an LBBB. The primary endpoint was evolution of the LVEF measured by echocardiography before implantation and between 6 and 12 months after TAVI. ResultsThe development of an LBBB was associated with a 5-point decrease in LVEF [−12.5; 2.5], contrary to the non-LBBB group (1.5 [−6.5; 9.5], P = 0.007) at 8 months, with the persistence of the LBBB (n = 23) exacerbating this decrease (−7 [−13; 2], P = 0.009). When left ventricular dysfunction (LVEF < 50%) was present before TAVI, the appearance of an LBBB was associated with a reduction in LVEF (−2 [−8; 2]) contrary to the non-LBBB group (20 [9; 22], P = 0.02). ConclusionsThe appearance of a new-onset LBBB after TAVI has a pejorative impact on left ventricular systolic function, particularly in patients with an initial LVEF < 50%, due to a lack of recovery of the latter, thereby potentially affecting their prognosis.

A Case of Acute-Onset Heart Failure Derived from Infective Endocarditis Coinciding With H1N1 Influenza Myocarditis

congestion derived from worse mitral valve regurgitation (MR) together with complete left bundle branch block (LBBB) and left ventricular (LV) dyssynchrony. As HF was relieved swiftly using pharmacological intervention and oxygen supplementation, MR was diminished and LBBB recovered to narrow QRS intraventricular conduction.Since cardiac resynchronization therapy (CRT) was introduced in July-2009, her clinical status has been stable without any cardiac events including HF hospitalization,and moreover, the enlarged and impaired LV has gradually reversed together with reduced MR. Although intermittent LBBB is caused by changes in the heart rate, autonomic nervous tone or myocardial ischemia,, there have been few reports concerning deteriorated HF of contributing the appearance of LBBB except in some cases of acute pulmonary embolism. LV dyssynchrony by sudden onset of LBBB could induce not only decrease contraction of LV but also increased MR through interfering with the proper closure of the mitral valve, leading to exacerbation of HF. CRT is a reliable, therapeutic option in cases with intermittent LBBB coincident with acutely-decompensated HF.

Clinical-electrocardiographic correlates of newly acquired left bundle branch block: The Framingham study

To determine whether any associated electrocardiographic findings in persons with newly acquired complete left bundle branch block (LBBB) correlate with the prevalence of associated clinically apparent cardiovascular abnormalities, electrocardiograms (ECGs) from all 55 members of the Framingham Study cohort in whom LBBB developed during 18 years of routine prospective biennial examinations were reviewed. A QRS axis left of or equal to 0 °, left atrial conduction delay and an inverted T wave in lead V 6 on the first ECG with LBBB, and an abnormal ECG in the Framingham examination preceding the appearance of LBBB each correlated with the prevalence of systemic hypertension, cardiomegaly, coronary heart disease and congestive heart failure. However, neither the PR interval nor the duration of the QRS complex on the first ECG with LBBB correlated with the prevalence of any of the associated cardiovascular abnormalities. The 8 patients with neither left atrial conduction delay nor a QRS axis left of or equal to 0 ° on the first Framingham ECG with LBBB nor an abnormal ECG on the examination preceding the appearance of LBBB were 6 times more likely to remain free of all of the clinical cardiovascular abnormalities than the 47 patients with 1 or more of these 3 electrocardiographic findings (p < 0.001).

Chest Pain and Rate-Dependent Left Bundle Branch Block in Patients with Normal Coronary Arteriograms

A triad of exertional chest discomfort, transient rate-dependent left bundle branch block (LBBB), and normal coronary arteries is presented in seven consecutive patients. Although the clinical symptoms resembled effort angina, qualities atypical of classic angina pectoris were commonly noted: 1) the onset was always abrupt; and 2) the pain was local, never radiating; 3) palpitation; and 4) "walk through" phenomenon were often present. The abrupt pain took place simultaneously with the appearance of LBBB induced by physical exercise in all seven patients. Atrial pacing or spontaneous resting heart rate changes produced similar sensations and LBBB in four of the five patients examined in this way. Similarly, in the same four patients kinetocardiographic recordings disclosed a sudden occurrence of paradoxic cardiac movement at the moment LBBB and chest pain appeared. The paradoxic systolic motion disappeared at reversion to normal conduction.

The Delay in the Korotkoff Sounds in Left Bundle-Branch Block

A means for the indirect definition of the calibrated, timed contour of the leading edge of the pattern of the Korotkoff sounds was used to examine the timing of the pressure wave in 30 patients with cardiac disease. Following the onset of the QRS complex (Q) of the electrocardiogram in normal subjects, the Korotkoff sounds (K) in the brachial artery at diastolic pressure (QK_d) appeared at 195 ± 18 msec. The QK_dwas earlier than normal in patients with arteriosclerosis or subaortic muscular stenosis; QK_dwas delayed in subjects with myocardiopathies. The appearance of left bundle-branch block (LBBB) in these patients was associated with a delay in the QK_dof approximately 60 msec. The QK_dwas delayed by 40 to 90 msec during episodes of intermittent LBBB in four subjects, with return to earlier values when conduction returned to normal patterns.