ANGIOSCOPIC DETECTION OF RESIDUAL PULMONARY THROMBI IN THE DIFFERENTIAL-DIAGNOSIS OF PULMONARY-EMBOLISM

Definite diagnosis of pulmonary embolism (PE) by conventional methods such as angiography is frequently difficult. If residual thromboemboli incorporated into the pulmonary arterial wall or in the distal small segments are visible, differential diagnosis of PE versus primary pulm onary hypertension (PPH) can be made without open-chest pulmonary biop sy. Six patients suspected of having acute PE, 6 suspected of having c hronic PE, and 4 with PPH diagnosed by pulmonary biopsy underwent perc utaneous pulmonary angioscopy. In patients suspected of having PE, glo bular and mural thromboemboli were detected by both angioscopy and ang iography in 4 and 1 patients, respectively. By angioscopy, emboli inco rporated into the arterial wall were detected in 7 and microemboli obs tructing the distal small segments were detected in 6. However, these emboli were detected by angiography in none. In patients with PPH, no embolus was detected by angioscopy and angiography. Angioscopically, h owever, stenoses were observed in the distal small segments in all pat ients. The results indicate that residual pulmonary thromboemboli in P E and stenoses of distal pulmonary arteries in PPH are detectable by p ercutaneous angioscopy, and therefore this method is feasible for diff erential diagnosis of PE.