The past quarter century has seen a surge in the available data on hypertrophic cardiomyopathy (HCM), with the evolution of comprehensive HCM-related management strategies that have expanded the diagnostic tools and risk stratification algorithms available for use. In addition to employing genotype-to-phenotype nosology to describe HCM, modifications to the current MOGE(S) classification for HCM based on the presence or absence of obstruction and location of hypertrophy within the morphology have been suggested. These available tools, including genetic testing, have led to a greater appreciation for at-risk patients, including susceptible family cohorts. Greater recognition is being paid to the development of pulmonary hypertension in HCM, based primarily on pathophysiology related to heart failure with preserved ejection fraction. In addition, there has been resurgence in the description and recognition of right ventricular outflow pathology in HCM and its associated treatment dilemma. Although slow, a trend to recognize HCM as a treatable disease with a more favorable prognosis is emerging as the sudden death risk stratification process continues to be honed with putative additions of such risk markers as obstructive sleep apnea. This chapter focuses on our current understanding of right-sided heart pathology in HCM, including an expanded debate on sleep apnea as a risk factor for sudden death and intractable symptomatology. The unique mechanistic considerations thereof are presented.