Atrial natriuretic peptide and vasopressin during percutaneous transvenous mitral valvuloplasty and relation to renin-angiotensin-aldosterone system and renal function

Plasma levels of adrenomedullin in patients with mitral stenosis

Although plasma levels of adrenomedullin are elevated in patients with heart failure, levels in patients with mitral stenosis are unknown. We determined plasma levels of adrenomedullin in specimens of blood obtained from the peripheral veins of 15 consecutively treated patients with mitral stenosis 1 week before and 1 week after percutaneous mitral valvuloplasty. We also measured adrenomedullin in blood obtained from the right and left atria of 13 of 15 patients immediately before valvuloplasty. Plasma adrenomedullin level in the peripheral vein was 27.3 +/- 3.2 pg/ml among healthy subjects (n = 15) and 59.8 +/- 2.7 pg/ml among patients with mitral stenosis (n = 15, p < 0.0001). Plasma adrenomedullin level in the peripheral veins of patients with mitral stenosis before valvuloplasty correlated significantly with mean pulmonary artery pressure, mean pulmonary arterial wedge pressure, and mean left atrial pressure. Plasma levels of adrenomedullin in the peripheral vein and the right atrium were significantly higher than those in the left atrium (59.5 +/- 3.0 and 55.8 +/- 2.4 versus 45.9 +/- 2.9 pg/ml, n = 13, p < 0.005). Percutaneous mitral valvuloplasty caused a significant decrease in plasma adrenomedullin levels in peripheral veins from 59.8 +/- 2.7 to 49.9 +/- 3.1 pg/ml (p < 0.02). Percentage decrease in plasma adrenomedullin levels in the peripheral vein correlated significantly with percentage decreases in mean pulmonary artery pressure and mean pulmonary arterial wedge pressure. This study demonstrated that plasma adrenomedullin levels of patients with mitral stenosis correlated positively with mean pulmonary artery pressure and pulmonary arterial wedge pressure. These findings suggested that adrenomedullin may play an important role in the pulmonary circulation of these patients.

Acute and delayed hormonal changes in mitral stenosis treated by balloon valvulotomy

The role of left atrial and aortic pressures on the secretion of the main hormones controlling blood volume is still subject to debate in humans. Because of increased mean left atrial pressure and decreased mean aortic pressure produced by balloon inflation in patients with mitral stenosis treated with balloon valvulotomy, the hormonal changes occurring acutely (group II of patients) were measured. The same studies (group I patients) were also performed 48 hours after this treatment, a period at which left atrial pressure permanently diminished. Inflation of the balloon resulted in a decrease in plasma renin activity and increases in plasma atrial natriuretic factor (ANF) and plasma arginine vasopressin (AVP). Forty-eight hours after balloon valvulotomy, which had produced a decrease in left atrial pressure, plasma ANF was lower (58.9 +/- 7.9 vs 95.3 +/- 11.9 pg/ml; p < 0.001), and plasma renin activity (2,575 +/- 533 vs 960 +/- 113 pg/ml/hour; p < 0.01), plasma angiotensin II (25.0 +/- 4.1 vs 9.3 +/- 1.3 pg/ml; p < 0.001) and plasma aldosterone (181.7 +/- 36.7 vs 139.9 +/- 19.8 pg/ml; p < 0.05) were higher than their respective control levels 24 hours before treatment of the stenosis. In contrast, plasma AVP (3.7 +/- 0.25 vs 4.4 +/- 0.31 pg/ml; p = 0.001) diminished moderately along with plasma osmolality (282.4 +/- 0.1 vs 286.2 +/- 0.6 mOsm/kg; p < 0.001). Urinary sodium excretion was also examined before and after balloon valvulotomy.(ABSTRACT TRUNCATED AT 250 WORDS)

Relationship between plasma atrial and brain natriuretic peptide concentration and hemodynamic parameters during percutaneous transvenous mitral valvulotomy in patients with mitral stenosis

Brain natriuretic peptide (BNP), a family of peptides with structural and biologic homologies to previously identified atrial natriuretic peptide (ANP), has been found in human cardiac tissue and plasma. To examine the secretion mechanism of these peptides, we have studied the relationship between their plasma concentrations and hemodynamic parameters before and at 0.5 and 24 hours after percutaneous transvenous mitral commissurotomy (PTMC) in 14 patients with mitral stenosis. We have also investigated the validity of measuring plasma natriuretic peptides as a means for estimating changes in hemodynamic parameters after PTMC. The procedure decreased left atrial pressure (p < 0.01) with an elevation in left ventricular end-diastolic pressure (p < 0.05). Plasma ANP levels decreased significantly after PTMC (before, 64.1 +/- 33.7 fmol/ml; at 0.5 hour, 58.9 +/- 27.7 fmol/ml; at 24 hours, 45.7 +/- 18.3 fmol/ml; p < 0.01), whereas plasma BNP levels remained unchanged after the procedure (before, 5.3 +/- 1.5 fmol/ml; at 0.5 hour, 5.6 +/- 1.9 fmol/ml; at 24 hours, 5.0 +/- 1.9 fmol/ml; p = NS). There was a significant relationship between basal plasma ANP and left atrial pressure (r = 0.88; p < 0.001), and changes in plasma ANP were correlated with those in left atrial pressure (r = 0.69; p < 0.01). Basal plasma BNP was significantly correlated with basal left ventricular end-diastolic pressure (r = 0.65; p < 0.05) but not with the other measured hemodynamic parameters or with plasma volume.(ABSTRACT TRUNCATED AT 250 WORDS)