This chapter explores left-sided abnormalities, discussing venoatrial abnormalities (including partial anomalous pulmonary venous drainage, total anomalous pulmonary venous drainage, and left-sided SVC), atrioventricular abnormalities (mitral atresia and mitral hypoplasia), ventriculoarterial abnormalities (including aortic stenosis, aortic atresia, and hypoplastic le. heart syndrome), and arterial abnormalities (coarctation of the aorta, interrupted aortic arch, right aortic arch, aberrant subclavian artery, double aortic arch, persistent fifth aortic arch, vascular rings, and aorto-pulmonary window).