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Left bundle branch block (LBBB) has a perceived unfavorable result and is connected with hypertension, Coronary Artery Disease (CAD), idiopathic dilated cardiomyopathy, aortic stenosis and degenerative ailment of the conductive framework.
Diagnostic coronary angiography has gotten to be one of the essential tools of heart catheterization; coronary angiography remains the clinical highest quality level for the diagnosis of CAD.
The current study aimed to determine association between complete LBBB, CAD severity, site and CAD risk factors. Because the presence of complete LBBB makes the non-invasive identification of CAD less informative, patients with complete LBBB often are referred for coronary angiography to assess the presence and severity of CAD.
In our study, patients were selected out of those referred to routine laboratories and echocardiographic examination in our hospitals for diagnosis and evaluation of CAD, during the period between November 2014 and October 2016. The study was conducted in 80 patients with LBBB, 52 males (65%) and 28 females (35%) with their age ranged from 39 to 77 years with a finding of coronary angiography into two groups:
Group I: included 56 patients (37 males and 19 females) with significant CAD (diameter of stenosis ≥70% in one or more epicardial vessels.
Group II: included 24 patients (15 males and 9 females) with normal coronary arteries.
All patients underwent thorough history taking and full clinical examination, standard 12 resting ECG, laboratory investigation, chest X-ray, echocardiography and coronary angiography.
The clinical and demographic characteristics of both groups were comparable; there was male preponderance in both groups. The risk factors of CAD were more in group I than in group II.
In our study CAD 56 (70%), left ventricular systolic dysfunction (LVSD) 51 (63.8%). Hypertension found in 38 (47.5%), diabetes mellitus (DM) in 31 (38.8%), DM and left ventricular systolic dysfunction (LVSD) were more associated with significant CAD.
In our study:
1-LBBB was more common in elderly, male and hypertensive patients.
2-LBBB was significantly associated with a significant coronary lesion in elderly, diabetics and hypertensive so these risk factors are a strong predictor of CAD in LBBB.
Coronary angiography detected LAD artery lesion in 49 patients (87.5%), LCX artery lesions in 15 patients (26.7%) and RCA artery lesions in 14 patients (25%). So:
3-LAD was the most frequently diseased artery and to less extent LCX and RCA.
In our study coronary angiography detected single vessel disease lesion in 37 patients (46.2%), two vessel disease lesion in 16 patients (20%), three vessel lesion in 3 patients (3.8%) and normal vessels in 24 patients (30%). So:
4-Frequency of single vessel disease was high in this study. There was no involvement of LMCA.
1. Our Study does not favor the hypothesis that presence of LBBB with coronary artery disease predicts the severity of coronary artery disease (in terms of LMCA, involvement or three-vessel disease).
Side effects were minimal and transient, no major complications in the form of mortality, infarction or serious arrhythmias have occurred.
There is a significant association between coronary artery disease and LBBB and since the patients with ECG evidence of LBBB have an increasing risk of left ventricular dysfunction and reduced survival rate, therefore we recommend that:
1. Coronary angiography should be considered in patients with LBBB who have ischemic chest pain or who have risk factors for CAD.
2. Invasive Coronary angiography is often needed to confirm or defer obstructive CAD in patients with LBBB for accurate diagnosis.
3. Since the number of cases in the present study was limited, further work is needed on a large number of patients to evaluate and support the results of this study.
Coronary angiography is a major and invasive diagnostic tool for CAD present in tertiary centers so selection criteria are required to clarify patients with LBBB who are likely to be at risk of CAD and need this invasive procedure, on the other hand, avoid over diagnosis of CAD, unnecessary hospital admissions and consumption of anti-anginal medication.