Significance of left ventricular inflow gradients in patients with ventricular septal defect.

Hemodynamic data of 167 patients of isolated ventricular septal defect (VSD) was retrospectively analyzed for the presence of left ventricular inflow gradients. End diastolic gradients of > 5 mm Hg between the pulmonary artery wedge pressure and the left ventricular end diastolic pressure were recorded in 40 of these patients. In three of these cases, left atrium was also entered and identical pressure gradients were recorded between the left atrial pressure and the left ventricular end diastolic pressure. Two dimensional and Doppler echocardiographic or operative findings were available in 32 of the 40 patients. No statistical correlation was found between the presence and degree of left ventricular inflow gradients at end diastole and the degree of left to right shunt. Out of a total of 40 patients with left ventricular inflow gradients, gradients of 6-10 mm Hg were present in 24 patients. Echocardiographic or operative findings available in 19 of these did not show any left ventricular inflow obstruction. Enddiastolic gradients of 11-15 mm Hg were present in 14 patients. Echocardiographic or operative findings were available in 11 of these and one of these had congenital mitral stenosis at surgery. End diastolic gradients of more than 15 mm Hg were present in 2 patients and one of these had congenital mitral stenosis at surgery. Thus organic left ventricular inflow obstruction is rare with inflow mitral gradients of upto 15 mm Hg in patients of VSD.