Tall peaked T waves
Tall peaked T waves are seen in leads V2-V4 (C2-C4). In addition there is prominent negative component for P wave in lead V1 (C1) suggestive of left atrial enlargement and tall R waves in V5, V6 (C5, C6) indicating left ventricular hypertrophy. Tall T waves could occur both in hyperkalemia and hyperacute phase of acute myocardial infarction. Occasionally tall T waves are seen as normal variants as well. Tall T waves in lateral leads along with tall R waves may be noted in left ventricular volume overload. But in this ECG tall T waves are not seen in the leads with tall R waves. In hyperacute phase of myocardial infarction, the tall T waves have associated ST segment elevation or a rapidly upsloping ST segment (Pardee’s sign ). Sometimes it may be seen in hypertrophic cardiomyopathy as well, though more common finding in hypertrophic cardiomyopathy is giant T wave inversion.
Rarely, tall T waves can occur in acidosis without hyperkalemia . In this study amplitude of T wave in V2 was positively correlated with hydrogen ion concentration. These T waves were also symmetrical and narrow based, the so called ‘tent shaped T waves’. The T waves were taller during acidosis than after correction.
In this ECG, in addition to tall T waves (more peaked than in previous ECG), QRS complex is wide and has left bundle branch block pattern. There is ST segment depression and T wave inversion in the lateral leads, though the T waves are very tall and peaked in mid precordial leads. Left bundle branch block pattern is characterized by the wide notched QRS complexes in lead V6 with secondary repolarization abnormality in the form of ST segment depression and T wave inversion. the opposite pattern of a wide S wave with upsloping ST and upright T is seen in V1.
- Pardee HEB. An electrocardiographic sign of coronary artery obstruction. Arch Intern Med 1920; 26: 244– 257.
- Dreyfuss D, Jondeau G, Couturier R, Rahmani J, Assayag P, Coste F. Tall T waves during metabolic acidosis without hyperkalemia: a prospective study. Crit Care Med. 1989 May;17(5):404-8.