Long-term outcome of patients operated for large ventricular septal defects with increased pulmonary vascular resistance.

BACKGROUND: There is a paucity of data regarding the long-term outcome of patients operated for ventricular septal defect with severe pulmonary arterial hypertension and elevated pulmonary vascular resistance. METHODS AND RESULTS: We evaluated the long-term follow-up results of a selected cohort of patients with nonrestrictive ventricular septal defect and elevated pulmonary vascular resistance (>6 Wood units). Thirty-eight patients, median age 7.5 years (range 6 months-27 years), with nonrestrictive ventricular septal defect with severe pulmonary hypertension were operated between 1985 and 1996 at our institute. Preoperative pulmonary vascular resistance, ratio of pulmonary blood flow to systemic blood flow, and ratio of pulmonary vascular resistance to systemic vascular resistance were 7.63+/-1.8 Wood units, 1.9+/-0.48, and 0.41+/-0.12, respectively. The majority (68.4%) had perimembranous ventricular septal defect. Thirty patients (79%) had a good outcome and were asymptomatic at a mean follow-up of 8.7 years, with significant reduction in pulmonary artery pressures. Eight patients (21%) had a poor outcome, which included 5 immediate postoperative deaths, 1 late death and 2 surviving patients with persistent severe pulmonary arterial hypertension. There was no significant difference regarding hemodynamic parameters at baseline between those who had a good outcome and those who did not. Eleven patients with a preoperative pulmonary blood flow to systemic blood flow ratio of <2:1. who had a good outcome following surgery, underwent repeat catheterization at follow-up. There was a significant reduction in their mean pulmonary vascular resistance (8.03+/-1.4 v. 4.16+/-1.6 Wood units, p=0.001) and pulmonary vascular resistance to systemic vascular resistance ratio (0.41+/-0.12 v. 0.19+/-0.06, p=0.05). CONCLUSIONS: The late results of surgery on this selected group of patients with nonrestrictive ventricular septal defect with high pulmonary vascular resistance are encouraging. Operative correction of the ventricular septal defect should be actively considered in all children presenting with nonrestrictive ventricular septal defect with a significant left-to-right shunt, despite moderately elevated pulmonary vascular resistance. Even among older patients with ventricular septal defect and moderately elevated pulmonary vascular resistance, there is a specific group that does well after operation.

Left atrial and pulmonary artery wedge pressure monitoring during balloon mitral valvuloplasty.

OBJECTIVE: We tested the accuracy of pulmonary artery wedge (PAW) pressure as a guide to the degree of pulmonary venous hypertension. METHODS: Left atrial (LA) pressure and PAW pressure were analysed before and after balloon mitral valvuloplasty (BMV) in patients with rheumatic mitral stenosis. RESULTS: Correlations between LA and PAW pressures for a wave, v wave and mean pressure were excellent before BMV (r=0.96, r=0.97 and r=0.99 respectively) and after BMV (r=0.98, r=0.98 and r=1.00 respectively). The fall in mean LA pressure (11.3 +/- 7.9 mm Hg) and in mean PAW pressure (11.1 +/- 7.9 mm Hg) also correlated well. Correlation was good both before and after BMV when subgrouping was done based on average pulmonary vascular resistance and average LA mean pressure in each group. CONCLUSIONS: There is good correlation of PAW pressure with LA pressure even in the presence of pulmonary arterial or venous hypertension. It can replace LA pressure monitoring in any clinical setting.

Atrial fibrillation in patients with pure isolated severe rheumatic mitral regurgitation.

OBJECTIVE: This study examines the significance of the parameters that identify patients with mitral regurgitation (MR) and atrial fibrillation (AF) and discusses the indications for surgery in such patients. METHODS: Patients with MR and chronic AF (group I, n=64) and those without AF (group II, n=138) were studied by clinical and echocardiographic methods. Stepwise regression analysis identified factors associated with the presence of atrial fibrillation. RESULTS: Group I patients were older and more symptomatic. They had larger left ventricular (LV) end systolic dimension (4.6+/-1.1 cm vs 3.8+/-0.8 cm, p=0.03), left atrial (LA) dimension (5.4+/-2.0 cm vs 4.1+/-1.3 cm, p=0.02), LA area (55.9+/-27.1 cm2 vs 35.9+/-17.5 cm, p=0.003) and lower LV ejection fraction (58.8+/-8.0% vs 72.4+/-7.4%, p=0.0003). Right ventricular systolic pressure was higher (57.6+/-18.1 mm Hg vs 33.6+/-12.1 mm Hg, p=0.02). By stepwise regression analysis, factors that predicted the presence of AF were age (p < 0.03) and LA dimension (p < 0.01). A higher LV end systolic dimension and lower LV ejection fraction than the recommended value for good operative outcome were present in them. Emerging indications for surgery and predictors of poor outcome were seen. CONCLUSIONS: Atrial fibrillation in MR indicates a more chronic and severe disease process with worsening of left as well as right sided haemodynamics in spite of digoxin. Drifting towards decompensation, these patients are likely candidates for early surgery.

Simultaneous echocardiographic and catheterisation gradients and mitral valve area during balloon mitral valvuloplasty.

This study was aimed at estimating mean transmitral gradients by simultaneous Doppler echocardiography and cardiac catheterisation and determining mitral valve area by pressure half time, Gorlin's formula and two-dimensional echocardiography so as to assess the relative accuracy of these methods before and after balloon mitral valvuloplasty in patients with rheumatic mitral stenosis. Left atrium-left ventricular, pulmonary artery wedge-left ventricular and echo gradients were simultaneously recorded in 18 patients undergoing balloon mitral valvuloplasty. Mitral valve area was estimated by pressure half time, Gorlin's equation and two-dimensional echocardiography. The correlation between left atrium-left ventricular and echo mean gradient before balloon mitral valvuloplasty was 0.96 (p < 0.03). Between pulmonary artery wedge-left ventricular and echo mean gradient, it was 0.95 (p < 0.04). The correlations between left atrium-left ventricular and pulmonary artery wedge-left ventricular mean gradient were also good. After balloon mitral valvuloplasty, similar good correlations were seen. On subgrouping the patients into those with high and low pulmonary artery pressure, good correlation persisted both before and after balloon mitral valvuloplasty. Mitral valve area by all the methods were similar before balloon mitral valvuloplasty. After balloon mitral valvuloplasty, mitral valve area by pressure half time was the least and by two-dimensional echocardiography, the maximum. All the three methods are equally accurate in estimating transmitral gradients and mitral valve area in mitral stenosis before balloon mitral valvuloplasty. Two-dimensional echocardiography is the best to estimate mitral valve area after balloon mitral valvuloplasty. Echocardiography can replace haemodynamic measurement of gradients and mitral valve area before and after balloon mitral valvuloplasty. But pressure half time is not recommended for measuring mitral valve area immediately after balloon mitral valvuloplasty where two-dimensional echocardiography mitral valve area is to be employed.

Effect of atrial septal defect created during balloon mitral valvuloplasty on calculation of cardiac output and mitral valve area.

We studied the effect of atrial septal defect (ASD), produced during transseptal puncture, on estimation of cardiac output (CO) and mitral valve area (MVA), after successful balloon mitral valvuloplasty (BMV) using the Inoue balloon in 20 patients. Oximetry run, pressure gradients, thermodilution CO and MVA were measured initially while temporarily occluding the ASD by partially inflating the Inoue balloon catheter. Measurements were repeated after withdrawing the balloon catheter into the right atrium. Post-BMV cardiac output and MVA were similar in both the situations (4.52 +/- 1.37 L/min vs 4.50 +/- 1.19 L/min; 1.89 +/- 0.4 cm2 vs 1.93 +/- 0.38 cm2 respectively, p = ns). Only 2 patients showed a step up at atrial level on oximetry (9% and 16% respectively) but did not have significantly different CO or MVA, both with ASD occluded or otherwise. We conclude that the magnitude of ASD created during BMV by Inoue balloon technique is small and does not significantly affect the estimation of CO or MVA if the septal puncture is done in the fossa ovalis area.