Pathologic obstruction of the proxi...

Pathologic obstruction of the proximal lumen and secondary atrophy of the media of the peripheral small pulmonary arteries were absolute operative contraindications in cases of VSD and/or PDA with sharp pulmonary hypertension. Such patients who were operated forward died with no decrease in pulmonary arterial urgency The index of pulmonary vascular disease (IPVD), a composite and quantitative evaluation of the severity of pulmonary vascular disease, was introduced to determine the operability of other patients. An IPVD rating of 22 in Down's syndrome and 21 without the syndrome were regarded as the upper permissible limits for surgical intervention based forward results of 23 autopsies and 26 lung biopsies of patients operated upon before 1981. Open lung biopsy was performed in 51 patients to determine applicability of our operative indications. Twenty-nine cases were considered operable by means of our criteria, and 28 underwent surgical correction without operative or late death. Twenty-two cases notion inoperable remain under observation. Comparative analysis of the pathology and preoperative hemodynamic data intimateed that lung biopsy should be carried gone out to determine operability in cases with pulmonary vascular resistance greater than 8 units*[m.sup.2].

(Chest 1989; 96:31-39)

equable today there are problems involved in the hemodynamic determination of operability in cases of congenital heart disease with inexorable pulmonary hypertension. The Heath-Edwards (HE) classification,[1] histopathologic criteria in widespread clinical use, can provide single qualitative information about plexogenic pulmonary arteriopathy and consequently has limitations for use in determining operability.

We previously unraveled our own histopathologic criteria for determining operability in cases of transposition of the great arteries (TGA) and secundum atrial septal fault (ASD), based on open lung biopsy findings.[2,3] The at hand study was undertaken to establish similar criteria for ventricular septal blemish (VSD) and patent ductus arteriosus (PDA), using the same lung biopsy technique. We also focus onward operative and late postoperative flows of cases in whom diagnosis was based forward open lung biopsy and forward the relationship between pathologic findings and conventional hemodynamic measures.

Patients and Methods

Patients

Clinical controls included 100 cases of PDA and/or VSD with sharp pulmonary hypertension, 49 of whom underwent surgery before 1981 and 51 of whom experienced lung biopsy or lung biopsy and surgery between 1981 and 1988 Of the total 100 cases, 31 also exhibited Down's syndrome There were 63 cases of VSD 16 cases of PDA, and 21 cases of VSD in conjunction with PDA. Ages ranged from 2 month to 61 years, with a mean age of 82 years.

Among the 49 pre-1981 cases, in 26 lung biopsy was performed during corrective surgery which the patients survived (Table 1) There were 19 operative deaths and four late deaths to be paid to plexogenic pulmonary arteriopathy; autopsies were performed in all cases (Table 2) The criteria for operative indications were determined upon the basis of the flows of these 49 cases.

In the 51 cases between 1981 and 1988 operability was determined based forward open lung biopsy findings using the previously determined criteria (Table 3)

Histopathologic Sections

As a order a 2 x 1 x 15-cm specimen of lung tissue was obtained from the right median lobe in the one and the other cases of biopsy and autopsy and fixed in 10 percent formalin. The tissue was then divided into three parts and embedded in paraffin. pace sections of each block were made at 50-[mu] intervals, yielding a total of about 60 histologic sections through case. Staining was done using the Elastica-Goldner method

Determination of the Severity of Plexogenic Pulmonary Arteriopathy

Determination of the severity of plexogenic pulmonary arteriopathy was made using the index of pulmonary vascular disease (IPVD).[4,5] That is, pulmonary vascular disease in the small pulmonary arteries was measured for each histologic section and classified into single of four grades. A rating of 1 to 4 was assigned to each small pulmonary artery and a mean rating obtained for each case. These ratings corresponded to the following pathologic findings: (1) no [TABULAR DATA OMITTED] hypertrophy of the intima of small pulmonary arteries; (2) cellular proliferation of the intima of small pulmonary arteries; (3) fibrous thickening of the intima of small pulmonary arteries; and (4) destruction of the media of small pulmonary arteries. Evaluation of the lesions was also made using the HE classification, and this was compared with the IPVD springs [TABULAR DATA OMITTED]

Results

Establishing Criteria for Lung Biopsy Diagnosis

Criteria for lung biopsy diagnosis were established forward the basis of the 49 cases experienced prior to 1981 Of the 19 cases of operative death, nine showed no significant decreases in postoperative pulmonary arterial urgency In these cases, there was nearly total obstruction of the vascular lumen of pulmonary arteries with diameters of 100-200 [mu] becoming to intimal proliferation, and more peripherally located small pulmonary arteries showed thinner media, ie, secondary atrophy of the peripheral media (Fig 1) These findings strenuously suggested that pulmonary arterial compressing was high at locations proximal to the region of obstruction, further that more peripherally there was a decrease in pulmonary vital fluid flow and pressure.