Fragmentation of Massive Pulmonary Embolism Using a Pigtail Rotation Catheter: Discussion

21 Jul

Patient 1 died from sepsis and multiorgan failure after the 48-h interval. A direct relation to residues of pulmonary embolism seemed unlikely, as a control angiography 6 days after fragmentation demonstrated completion of recanalization. Overall mortality was 20% (48-h mortality, 10%), overall treatment success accounted for 80%, including a patient with brain death (due to a cardiac arrest of unknown duration) who became an organ donor later.
Several approaches have been made to establish a percutaneous catheter procedure. The first dedicated device was the Greenfield embolectomy catheter, introduced in 1969. Despite encouraging results, the catheter device did not achieve widespread use. Possible reasons include the need of a venotomy or a large (24F) introductory sheath, special skills in steering and pulmonary placement, and part removal of embolus, with the need of repositioning and subsequent passes. Click Here In a recent study, also employing the removal-by-suction technique, similar shortcomings were observed, as clot break-off during removal, especially during valve passage, and the need of several repeated passes.
There are a few studies describing patients with cardiogenic shock, which could be saved by perforating central emboli with guide wire and standard catheters. In another report, central emboli were compressed by balloon dilatation. Both techniques comprise fragmentation of central emboli with dispersal of the fragments to the periphery and led to partial hemodynamic improvement.
What are the possible advantages of a fragmentation therapy of central pulmonary emboli? Fragmentation of centrally located, large pulmonary emboli may lead to a partial recanalization of a complete occlusion. In comparison to the central main pulmonary arteries, the peripheral arteries at a level of 1 mm in diameter have approximately the twofold total cross-sectional area. In central emboli, which do not occlude completely, the dislocation of the ensuing fragments to the periphery may result in a relative gain of nonobstructed cross-sectional area. In patients threatened by right ventricular failure, even a small hemodynamic improvement may be life-saving and enlarges the critical time frame for further recanalization by medical thrombolysis. Besides the “plug removal” and the “dislocation-to-periphery” effects, there is the effect of increased total surface area of the resulting fragments, which may cause an increased efficacy of an accompanying thrombolysis or of spontaneous intrinsic lytic activity, if thrombolysis is contraindicated.