Catheter-Directed Thrombolytic Therapy vs Standard Anticoagulation in Intermediate Submassive Pulmonary Embolism: Looking for Rapid Clinical Responders

Abstract

This study aims to characterizes the clinical hemodynamic response patterns in patients with intermediate submassive pulmonary embolism (SM-PE) treated with catheter directed thrombolytic therapy (CDT) versus standard anticoagulation (SAC) with intravenous heparin. Hemodynamic compromise in SM-PE is reflected in the magnitude of tachycardia. The clinical data regarding more rapid clinical recovery with CDT versus SAC has not been fully delineated. METHODS: We retrospectively assessed for "Rapid Clinical Responders" (RCR, defined as heart rate (HR) reduction >25% at 24 hours) in patients with intermediate SM-PE (defined as RV strain indicated by RV/LV ratio > 1) in 75 patients treated with CDT versus 75 patients treated with SAC. RESULTS: Results showed a greater percentage of "Rapid Clinical Responders" in CDT group vs SAC group (72% vs 27%, p ¼ <0.0001). There was a greater HR reduction over 24 hours in CDT group with mean 105 bpm to 79 bpm, delta change 26 bpm, p<0.0001 vs SAC group with mean 95 bpm to 84 bpm, delta change 11bpm, p<0.001). Post therapy HR reduction achieved a statistically lower HR in the CDT group versus the SAC group (CDT mean 79 bpm vs SAC mean 84 bpm, p<0.007). CDT led to a significant reduction in tachypnea, which was not seen in the SAC group (CDT mean RR 24 þ/-2 to 18 þ/-1, p<0.0001 vs SAC mean 20þ/-1 to 19 þ/-1, p¼ 0.37). In hospital mortality rates were low in both groups (3.2% for CDT and 3% for SAC, respectively). Of note, length of stay was increased by 3þ/-1.5 days in the CDT group, which likely represents the severity of illness within this population in addition to increased complication rates such as bleeding (noted to be 9%). CONCLUSIONS: These findings demonstrates greater percentage of "Rapid Clinical Responders" in CDT group versus SAC group, with improved hemodynamic outcomes manifest as statistically significant reduction in tachycardia and tachypnea. CLINICAL IMPLICATIONS: These findings may have clinical implications regarding further optimization of care strategies to achieve improved hemodynamic outcomes in SM-PE.