A serious complication of percutaneous mitral valvuloplasty: systemic embolism. How can we decrease it? Case history.

Systemic embolism is a potential and severe complication of percutaneous balloon mitral valvuloplasty (PBMV). The incidence of systemic embolism during PBMV has been reported to be less than 5% and only 0.6% with the Inoue technique. This is less than that reported in closed commissurotomy series and about the same as in open commissurotomy. In the authors' series of 50 cases, the incidence of systemic embolism was 2% (1 case). The patient had mitral restenosis (after closed commissurotomy) with mild to moderate valvular and subvalvular calcification, and cerebral embolism occurred during the procedure. To prevent systemic embolism, the authors' standard policy was to perform transesophageal echocardiography (TEE), computed tomography, and magnetic resonance imaging before the procedure and to give heparin during the procedure and two months preceding it in cases with atrial fibrillation or with a history of previous embolism and to limit manipulation of the catheter in the left atrium. The authors believe that a close scrutiny in the selection of patients, improved technology of the dilating system, good experience with PBMV, and adequate heparinization are also of great importance in the prevention of thromboembolic complications.

Atrial natriuretic factor in high-altitude pulmonary hypertension: the influence of acute hypoxia on plasma atrial natriuretic factor, renin, and aldosterone concentrations in highlanders with initially normal or elevated pulmonary artery pressure and without evidence of right ventricular hypertrophy.

Since the renin-angiotensin-aldosterone system and atrial natriuretic factor are directly involved in the regulation of hemodynamics and structural alterations in the circulatory system, the interest of investigators in the observed changes in this system during exogenous hypoxia and the resultant development of high-altitude pulmonary hypertension is quite understandable. The authors measured the plasma levels of hormones from the major vasoconstrictor neurohumoral system and from one vasodilatory system and correlated them with hemodynamic variables in native highlanders of Tien-Shan.