Pulmonary Hypertension in Mitral Stenosis

Abstract

It is known that the pulmonary arterial pressure is raised in many patients with mitral stenosis, and that in a proportion of them the abnormal resistance to the blood flow in the pulmonary arterial bed gives rise to persistent pulmonary hypertension. Although this state, which may influence prognosis and prove important in the selection of patients for surgical treatment, has received some attention, it has not yet been adequately investigated.In a previous paper (Evans et al., 1957) we described the pulmonary vessels in 11 patients with solitary pulmonary hypertension. Our present paper is concerned with the state of these vessels in patients with mitral stenosis, with the significance of the changes, and with their recognition during life.The presence of naked-eye changes in the pulmonary arteries in mitral stenosis has long been recognized. Thus, Posselt (1909), reviewing all the cases of pulmonary arteriosclerosis published during the nineteenth century, found that mitral stenosis was responsible for 40 per cent of them. It was Parker and Weiss (1936) who first described the microscopical changes; they examined 23 cases and found severe pulmonary arterial lesions in five of them; these included atheroma complicated by thrombosis in the larger arteries, intimal thickening in the muscular arteries, and concentric cellular proliferation in the arterioles. Larrabee et al. (1949) reported arterial lesions in 18 out of 20 cases of well-established mitral stenosis, and remarked that they were most prominent in vessels of 0 15 to 0 05 mm. diameter. In neither of these investigations were the histological changes related to the presence or absence of pulmonary hypertension. Henry (1952) described the presence of an abnormal muscular coat in the arterioles in 40 per cent of 105 cases of mitral stenosis, but he found it in none of 70 control cases. This abnormality has also been reported by Soulie et al. (1953) and Heath and Whitaker (1955) have emphasized its association with pulmonary hypertension.Almost all workers are agreed that the walls of many of the muscular arteries in mitral stenosis appear abnormally thick and have described the change as medial hypertrophy. O'Neal et al. (1955) undertook a special study of the media of the small muscular pulmonary arteries in 67 cases of moderate or severe mitral stenosis whose average age was 55 years, and compared the findings with those in a control series of comparable age without heart disease. They selected for measurement muscular arteries that were situated near a bronchiole and in order to avoid the discrepancy introduced by variation in the degree of arterial contraction, they calculated the area of the media at each cross-section of the vessel. By this method they failed to demonstrate any significant difference in the amount of arterial media in the two series, and they concluded that although the arteries were smaller there was no medial hypertrophy. They were also unable to identify a medial coat in the arterioles.The relationship between the vascular chan...

Influence of pulmonary vascular disease and fibrosis on prognosis following closed mitral valvotomy

“…Factors which significantly affected the prognosis were high pulmonary artery pressures, high vascular resistance, and narrowing of the pulmonary arteries; but, above all, pulmonary fibrosis. The prognosis for patients with mitral incompetence was less favourable than for those without incompetence, especially if there was increased pulmonary vascular resistance and pulmonary hypertension with axis deviation in the electrocardiogram.That pulmonary vascular and parenchymal changes occur in patients with rheumatic heart disease is well established (Parker and Weiss, 1936;Evans and Short, 1957;Donald, Bishop, Wade, and Wormald, 1957;Aber and Campbell, 1965;McCredie, 1966); what is not well established is their influence on prognosis after mitral valvotomy.Larrabee, Parker, and Edwards (1949) considered that simple decompression of the engorged vessels by mitral valvotomy should be followed by early regression of such pulmonary vascular changes that had no,t become irreversible. This was supported by earlier correlations of lung biopsies with the clinical behaviour of patients after closed mitral valvotomy, which seemed to indicate that pulmonary vascular disease had little influence on prognosis (Enticknap, 1953;Denst, Edwards, Neubuerger, and Blount, 1954;Clowes, Hackel, Mueller, and Gillespie, 1953;Goodale, Sanchez, Friedlich, Scannell, and Myers, 1955); failure to achieve permanent success was ascribed largely to cardiac and not to pulmonary factors (Turner and Fraser, 1956; Woodl 1954;Learoyd, Blacket, Sinclair-Smith, Mills, Halliday, and Maddox, 1960).…”

“…That pulmonary vascular and parenchymal changes occur in patients with rheumatic heart disease is well established (Parker and Weiss, 1936;Evans and Short, 1957;Donald, Bishop, Wade, and Wormald, 1957;Aber and Campbell, 1965;McCredie, 1966); what is not well established is their influence on prognosis after mitral valvotomy.…”

“…That pulmonary vascular and parenchymal changes occur in patients with rheumatic heart disease is well established (Parker and Weiss, 1936;Evans and Short, 1957;Donald, Bishop, Wade, and Wormald, 1957;Aber and Campbell, 1965;McCredie, 1966); what is not well established is their influence on prognosis after mitral valvotomy. Larrabee, Parker, and Edwards (1949) considered that simple decompression of the engorged vessels by mitral valvotomy should be followed by early regression of such pulmonary vascular changes that had no,t become irreversible.…”

“…We have observed rapid relief of pulmonary hypertension after decompression of the engorged vessels and oedematous lung parenchyma following restoration of mitral valve function in patients with minimal vascular and parenchymal changes. On the other hand, severe vascular changes, pulmonary fibrosis, and impaired gas diffusion adversely affected the prognosis (Parker and Weiss, 1936;Larrabee et al, 1949;Evans and Short, 1957;Aber and Campbell, 1965).…”

Clinical, Electrocardiographic, and Radiological Evaluation of Pulmonary Hypertension in Patients with Mitral Stenosis

“…In mitral valve disease, the degree of clinical disability and the improvement following surgical relief (mitral valvotomy) are closely related to the level of pulmonary arterial pressure and its reduction, respectively.1)- 4) Measurement of pulmonary arterial pressure is, therefore, of importance in assessment of the severity of mitral valve disease and determining prognosis of the patients. The most reliable estimate of pulmonary artery pressure today is its measurement by right heart catheterization.…”