Patients with precapillary pulmonary hypertension (PPH) have classically been reported to have normal pulmonary mechanical function. We reviewed spirometric data from 8 patients with primary pulmonary hypertension and from 17 patients with chronic thromboembolic pulmonary hypertension. All patients had undergone right heart catheterization and pulmonary angiography. Five of the 8 patients with primary pulmonary hypertension demonstrated a severe restrictive ventilatory pattern with a mean vital capacity (VC) of 50.4% predicted and a mean total lung capacity (TLC) of 64.3% predicted. Five of the 17 patients with chronic thromboembolic pulmonary hypertension manifested a restrictive pattern with a mean VC of 68.0% predicted and a mean TLC of 75.3% predicted. We conclude that restrictive ventilatory defects occur more frequently than previously described in patients with PPH. The physiologic mechanism responsible for the restrictive ventilatory pattern is not clear.

The purpose of thls study was to evaluate a number of equlllbrlum radknucllda method. for analydng rlgM wntrkular rlzs utd functlon, In an attempt to dawmhm if m y of a variety of approach8 could .ccumtdy charactorb rlgM ventrkular hamodynamlcr. Fwtiaen patbnb bdng cllnlcrlly ev&mtmd tor eoronwy artery d b m w (N = Q), congestive cardlomyopathy (N = 2), valvular dlseasa (N = 2), or hrtnccvdkc shunts (N = 1) undowent blplae contmst rlgM ventrkulogmphy W M n g gated bkod pool Imaglng. F w r radlonuclide bchnlqucm ware examlmd end Incluckd: (1) a mnkutomatlc edge&ttlon algorithm using a vwkbk dgM wntrlculw rogkn-ot-lnterest and a rlgM wntrkular apical end dk.tolk background; (2) performance; however, validation with conventional contrast angiography has not been performed. The goals of this study were to compare several of these currently available radionuclide methods with biplane constrast right ventriculography and to assess the interobserver and intraobserver variability of each method studied. MATERIALS AND METHODS Patlent PopulatlonFifteen patients who were scheduled to undergo diasnostic cardiac catheterization were studied in a serial fashion. Indications for diagnostic catheterization included an assessment of: ischemic heart disease (N = 10); congestive idiopathic cardiomyopathy (N = 2); aortic stenosis (N = 2); and atrial septal defect (N = 1). None of these patients had historical, clinical, or laboratory findings that suggested pulmonary disease. ProtocolEach patient was prepared in the standard fashion for the cardiac catheterization, and received 10 mg of oral diazepam as premedication. The catheters (a #7 Cournand and #8F NIH) used for evaluation of right ventricular pressure and function were placed through a femoral vein. They remained in the pulmonary artery and the inferior vena cava, respectively, during the radionuclide study. Within 1 hr of completion of the diagnostic catheterization protocol, each patient underwent in vivo red blood cell labeling with 15 mg of stannous pyrophosphate and 15-20 mCi of technetium Wm. A single crystal, gamma scintillation camera (General Electric Porta Data Camera, Milwaukee, Wisconsin), equipped with a high sensitivity parallel hole collimator, was placed in the 45" left anterior oblique projection with slight (< 10") caudal tilt. The camera was equipped with a pulse-height analyzer set at 140 keV with a 20% "window." A modified V-5 electrode was used for EKG gating; the heart rate and rhythm were stable during the study (< 3 extrasystoles per min). Ten minutes of scintigraphic data were collected. Blood samples, for the purpose of ventricular volume determinations, were taken from the right heart catheter.Fifteen minutes following the radionuclide, the 8F NIH catheter was placed into the body of the right ventricle, and biplane cine right ventriculograms were performed (30" RAO and 60" LAO projections). Fifty-five milliliters of meglumine sodium diatriozate (Renografin-76) were injected over a 3-to 4-sec interval into the right ventricular chamber. Cineangiog...