As a heart disease caused by pulmonary arterial hypertension, pulmonary heart disease has a high incidence and poor clinical prognosis in the elderly. Including mechanical ventilation in the current clinical treatment of cor pulmonale, with the development of medical technology, traditional invasive mechanical ventilation has been pointed out to have certain clinical limitations, so new invasive and noninvasive sequential ventilation treatments are gradually being used. Applied in clinical practice, this article selected 96 patients with severe cor pulmonale in our hospital from January 2020 to May 2021 as the research object and conducted a randomized prospective study. The experimental results show that the two general methods can improve the blood gas index and pulmonary function index of patients with heart disease and pulmonary dysfunction, but the improvement of the above indexes by the sequence of action of gas therapy is better than that of conventional invasive mechanical ventilation.