Exhaled nitric oxide (NO) production in stable chronic obstructive pulmonary disease (COPD) has been loosely related to the severity of illness, being significantly reduced in the most severe cases. Pulmonary hypertension is associated with lower NO output from the lung. In this study expired NO was measured in patients with severe stable COPD with or without cor pulmonale (CP). Echocardiographic estimates of right heart function, lung function, diffusion capacity, respiratory muscle strength, and arterial blood gases were obtained in 34 consecutive patients with stable COPD (mean age, 68 +/- 7 yr). Expired NO was measured by chemiluminiscence to obtain fractional exhaled concentrations at peak (FENOp) and at plateau (FENOpl) points of the single-breath curve and resting NO output (V NO). All measurements of expired NO output, FENOp, FENOpl and V NO showed a negative correlation with both systolic pulmonary artery pressure (Pspa) (r = -0.51, -0.63, and -0.63, respectively, p < 0.01 for all) and right ventricle wall dimension (r = -0.41, -0.59, and -0.43, respectively, p < 0.05 for all), but not with any measurement of lung function. When the patients were divided according to the Pspa using a cutoff limit of 35 mm Hg, those subjects with CP showed lower FENOp (13.2 +/- 4.0 versus 36.7 +/- 30.8 ppb, p < 0.05), FENOpl (5.7 +/- 1.9 versus 8.9 +/- 4.7 ppb, p < 0.05), and V NO (69. 2 +/- 5.6 versus 107.6 +/- 14.6 nl/ min, p = 0.02) than did those with a normal resting Pspa. NO production from the airways was significantly lower and inversely related to development of CP in patients with severe COPD. Impaired endothelial release may account for the reduced levels of expired NO.

The autologous pericardium seems to be superior to rigid prosthetic rings for annuloplasty in MVR since it provides more favourable mitral annulus dynamics and preserves LV function during stress conditions. Effective and durable annular remodelling with the autologous pericardium is achieved up to 6 years from surgery, with no echocardiographic sign of degeneration in the long term. Further studies are required to compare biological versus flexible prosthetic rings in MVR.

We studied the changes in the plasma concentration of atrial natriuretic factor (ANF) and the urinary excretion of ANF, arginine vasopressin (AVP) and catecholamines in 22 children with congenital heart disease, divided into two groups. Group 1 included 11 children with congestive heart failure (CHF), treated with digitalis and diuretics. Group 2 included 11 children without CHF and without medical treatment. Each group was compared with a control group of 15 healthy, age-matched children. The plasma concentration of ANF was raised in both groups, but it was significantly higher in group 1 (235.5 +/- 82.9 pg/ml), compared to group 2 (48.4 +/- 29.4 pg/ml, P < 0.002). Urinary excretion of ANF was measurable in both groups and higher in group 1 (185.9 +/- 116.2 pg/kg per h) than in group 2 (48.5 +/- 30.7 pg/kg per h), but not significantly so. Urinary excretion of AVP and catecholamines was not different in children with congenital heart disease and healthy children. Twenty-four hours after surgery, plasma ANF diminished in group 1 (from 235.5 +/- 82.9 to 93.4 +/- 53.8 pg/ml, P < 0.003), but did not change in group 2. The urinary excretion of ANF was unchanged in both groups. In contrast, urinary excretion of AVP and catecholamines rose significantly in both groups. These data show that plasma ANF is increased in children with congenital heart disease, even in the absence of CHF. The measurement of urinary ANF is less reliable than a plasma assay. The postoperative increases in AVP and catecholamine urinary excretions could be responsible for the vasoconstriction and water retention typical of the postoperative period.