Table 4.

Differential diagnosis of J wave vs. Intra-ventricular conduction defect-mediated notch syndromes. (IVCD)

	J wave	IVCD-induced end QRS notch
Male Predominance	Yes	No
Average Age at Initial Presentation	Young adults	Older adults
Most common Morphology	dome-like smooth appearance	Relatively sharp appearance
Response to Change in Heart Rate	Bradycardia- and pause-dependent augmentation of J wave which may be accompanied by T wave inversion.	Tachycardia and prematurity-dependent augmentation of the notch
Structural Heart Diseases	Rare	Common History of myocardial infarction and/or cardiomyopathy