Basic Electrocardiography Normal and abnormal ECG patterns - Part 4

Các chẩn đoán điện tâm đồ mở rộng biventricular thậm chí còn khó khăn hơn so với mở rộng cô lập của một tâm thất, như các lực lượng chống đối gia tăng của cả hai tâm thất thường đối trọng chính mình hoặc ưu thế đáng chú ý của mặt nạ mở rộng một trong tâm thất hoàn toàn mở rộng khác. | 48 Chapter 8 A B VR VL VF Figure 39 ECG examples ofbiveritricular enlargement. A A 35-year-old patient with mitral stenosis and regurgitation aortic regurgitation and significant pulmonary hypertension with sinus rhythm. B A 42-year-old patient with mitral stenosis and regurgitation and tricuspid stenosis and regurgitation see the text . Biventricular enlargement pFigure 39 The electrocardiographic diagnosis of biventricular enlargement is even more difficult than that of isolated enlargement of just one ventricle as the increased opposing forces of both ventricles often counterbalance themselves or the notable predominance of one ventricle s enlargement masks completely the enlargement of the other. Diagnostic criteria The follow ng elrcrrocardiographic criteria suggest the diagnosis of biventricular enlargement 1 Tall R wave in V5 V6 with an ÂQRS shifted to the right 90 . The presence of aninferoposteriorhemiblock associatedwith left ventricular enlargement as weldasasthenicbodysbutldmustberuledout. 2 TaSUR waeewita sitVe V6addwleh an aSReatteeninVland Pwaveod biatrial enlargembnt Figure 39A . Ventricular enlargement 49 3 QRS complexes within normal limits but with significant repolarisation abnormalities negative T wave and depression of ST segment mainly when the patient presents atrial fibrillation. This type of ECG can be found in the elderly with advanced heart diseases and biventricular enlargement. 4 Smalls wave in VI with a deep s wave in V2 and predominant R wave in V5 and V6 togetherwith anAQRS shifted to the right in the frontal plane or an Si- Sn- Sin-type morphology Figure 39B . 5 Large voltages in intermediate precordial leads with tall R waves in the left precordial leads a frequent finding in patients with ventricular septal defects . It is explained by the existence of a wide and rounded QRS loop in the frontal plane with its final portion directed to the right. CHAPTER 9 Ventricular blocks Ventricular conduction disturbances or blocks Figures .